Linux kernel & device driver programming

Cross-Referenced Linux and Device Driver Code

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Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  1 /*
  2  *  libata-core.c - helper library for ATA
  3  *
  4  *  Maintained by:  Jeff Garzik <jgarzik@pobox.com>
  5  *                  Please ALWAYS copy linux-ide@vger.kernel.org
  6  *                  on emails.
  7  *
  8  *  Copyright 2003-2004 Red Hat, Inc.  All rights reserved.
  9  *  Copyright 2003-2004 Jeff Garzik
 10  *
 11  *
 12  *  This program is free software; you can redistribute it and/or modify
 13  *  it under the terms of the GNU General Public License as published by
 14  *  the Free Software Foundation; either version 2, or (at your option)
 15  *  any later version.
 16  *
 17  *  This program is distributed in the hope that it will be useful,
 18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 20  *  GNU General Public License for more details.
 21  *
 22  *  You should have received a copy of the GNU General Public License
 23  *  along with this program; see the file COPYING.  If not, write to
 24  *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 25  *
 26  *
 27  *  libata documentation is available via 'make {ps|pdf}docs',
 28  *  as Documentation/DocBook/libata.*
 29  *
 30  *  Hardware documentation available from http://www.t13.org/ and
 31  *  http://www.sata-io.org/
 32  *
 33  *  Standards documents from:
 34  *      http://www.t13.org (ATA standards, PCI DMA IDE spec)
 35  *      http://www.t10.org (SCSI MMC - for ATAPI MMC)
 36  *      http://www.sata-io.org (SATA)
 37  *      http://www.compactflash.org (CF)
 38  *      http://www.qic.org (QIC157 - Tape and DSC)
 39  *      http://www.ce-ata.org (CE-ATA: not supported)
 40  *
 41  */
 42 
 43 #include <linux/kernel.h>
 44 #include <linux/module.h>
 45 #include <linux/pci.h>
 46 #include <linux/init.h>
 47 #include <linux/list.h>
 48 #include <linux/mm.h>
 49 #include <linux/highmem.h>
 50 #include <linux/spinlock.h>
 51 #include <linux/blkdev.h>
 52 #include <linux/delay.h>
 53 #include <linux/timer.h>
 54 #include <linux/interrupt.h>
 55 #include <linux/completion.h>
 56 #include <linux/suspend.h>
 57 #include <linux/workqueue.h>
 58 #include <linux/jiffies.h>
 59 #include <linux/scatterlist.h>
 60 #include <linux/io.h>
 61 #include <scsi/scsi.h>
 62 #include <scsi/scsi_cmnd.h>
 63 #include <scsi/scsi_host.h>
 64 #include <linux/libata.h>
 65 #include <asm/semaphore.h>
 66 #include <asm/byteorder.h>
 67 #include <linux/cdrom.h>
 68 
 69 #include "libata.h"
 70 
 71 
 72 /* debounce timing parameters in msecs { interval, duration, timeout } */
 73 const unsigned long sata_deb_timing_normal[]            = {   5,  100, 2000 };
 74 const unsigned long sata_deb_timing_hotplug[]           = {  25,  500, 2000 };
 75 const unsigned long sata_deb_timing_long[]              = { 100, 2000, 5000 };
 76 
 77 static unsigned int ata_dev_init_params(struct ata_device *dev,
 78                                         u16 heads, u16 sectors);
 79 static unsigned int ata_dev_set_xfermode(struct ata_device *dev);
 80 static unsigned int ata_dev_set_feature(struct ata_device *dev,
 81                                         u8 enable, u8 feature);
 82 static void ata_dev_xfermask(struct ata_device *dev);
 83 static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
 84 
 85 unsigned int ata_print_id = 1;
 86 static struct workqueue_struct *ata_wq;
 87 
 88 struct workqueue_struct *ata_aux_wq;
 89 
 90 struct ata_force_param {
 91         const char      *name;
 92         unsigned int    cbl;
 93         int             spd_limit;
 94         unsigned long   xfer_mask;
 95         unsigned int    horkage_on;
 96         unsigned int    horkage_off;
 97 };
 98 
 99 struct ata_force_ent {
100         int                     port;
101         int                     device;
102         struct ata_force_param  param;
103 };
104 
105 static struct ata_force_ent *ata_force_tbl;
106 static int ata_force_tbl_size;
107 
108 static char ata_force_param_buf[PAGE_SIZE] __initdata;
109 /* param_buf is thrown away after initialization, disallow read */
110 module_param_string(force, ata_force_param_buf, sizeof(ata_force_param_buf), 0);
111 MODULE_PARM_DESC(force, "Force ATA configurations including cable type, link speed and transfer mode (see Documentation/kernel-parameters.txt for details)");
112 
113 int atapi_enabled = 1;
114 module_param(atapi_enabled, int, 0444);
115 MODULE_PARM_DESC(atapi_enabled, "Enable discovery of ATAPI devices (0=off, 1=on)");
116 
117 static int atapi_dmadir = 0;
118 module_param(atapi_dmadir, int, 0444);
119 MODULE_PARM_DESC(atapi_dmadir, "Enable ATAPI DMADIR bridge support (0=off, 1=on)");
120 
121 int atapi_passthru16 = 1;
122 module_param(atapi_passthru16, int, 0444);
123 MODULE_PARM_DESC(atapi_passthru16, "Enable ATA_16 passthru for ATAPI devices; on by default (0=off, 1=on)");
124 
125 int libata_fua = 0;
126 module_param_named(fua, libata_fua, int, 0444);
127 MODULE_PARM_DESC(fua, "FUA support (0=off, 1=on)");
128 
129 static int ata_ignore_hpa;
130 module_param_named(ignore_hpa, ata_ignore_hpa, int, 0644);
131 MODULE_PARM_DESC(ignore_hpa, "Ignore HPA limit (0=keep BIOS limits, 1=ignore limits, using full disk)");
132 
133 static int libata_dma_mask = ATA_DMA_MASK_ATA|ATA_DMA_MASK_ATAPI|ATA_DMA_MASK_CFA;
134 module_param_named(dma, libata_dma_mask, int, 0444);
135 MODULE_PARM_DESC(dma, "DMA enable/disable (0x1==ATA, 0x2==ATAPI, 0x4==CF)");
136 
137 static int ata_probe_timeout = ATA_TMOUT_INTERNAL / HZ;
138 module_param(ata_probe_timeout, int, 0444);
139 MODULE_PARM_DESC(ata_probe_timeout, "Set ATA probing timeout (seconds)");
140 
141 int libata_noacpi = 0;
142 module_param_named(noacpi, libata_noacpi, int, 0444);
143 MODULE_PARM_DESC(noacpi, "Disables the use of ACPI in probe/suspend/resume when set");
144 
145 int libata_allow_tpm = 0;
146 module_param_named(allow_tpm, libata_allow_tpm, int, 0444);
147 MODULE_PARM_DESC(allow_tpm, "Permit the use of TPM commands");
148 
149 MODULE_AUTHOR("Jeff Garzik");
150 MODULE_DESCRIPTION("Library module for ATA devices");
151 MODULE_LICENSE("GPL");
152 MODULE_VERSION(DRV_VERSION);
153 
154 
155 /**
156  *      ata_force_cbl - force cable type according to libata.force
157  *      @ap: ATA port of interest
158  *
159  *      Force cable type according to libata.force and whine about it.
160  *      The last entry which has matching port number is used, so it
161  *      can be specified as part of device force parameters.  For
162  *      example, both "a:40c,1.00:udma4" and "1.00:40c,udma4" have the
163  *      same effect.
164  *
165  *      LOCKING:
166  *      EH context.
167  */
168 void ata_force_cbl(struct ata_port *ap)
169 {
170         int i;
171 
172         for (i = ata_force_tbl_size - 1; i >= 0; i--) {
173                 const struct ata_force_ent *fe = &ata_force_tbl[i];
174 
175                 if (fe->port != -1 && fe->port != ap->print_id)
176                         continue;
177 
178                 if (fe->param.cbl == ATA_CBL_NONE)
179                         continue;
180 
181                 ap->cbl = fe->param.cbl;
182                 ata_port_printk(ap, KERN_NOTICE,
183                                 "FORCE: cable set to %s\n", fe->param.name);
184                 return;
185         }
186 }
187 
188 /**
189  *      ata_force_spd_limit - force SATA spd limit according to libata.force
190  *      @link: ATA link of interest
191  *
192  *      Force SATA spd limit according to libata.force and whine about
193  *      it.  When only the port part is specified (e.g. 1:), the limit
194  *      applies to all links connected to both the host link and all
195  *      fan-out ports connected via PMP.  If the device part is
196  *      specified as 0 (e.g. 1.00:), it specifies the first fan-out
197  *      link not the host link.  Device number 15 always points to the
198  *      host link whether PMP is attached or not.
199  *
200  *      LOCKING:
201  *      EH context.
202  */
203 static void ata_force_spd_limit(struct ata_link *link)
204 {
205         int linkno, i;
206 
207         if (ata_is_host_link(link))
208                 linkno = 15;
209         else
210                 linkno = link->pmp;
211 
212         for (i = ata_force_tbl_size - 1; i >= 0; i--) {
213                 const struct ata_force_ent *fe = &ata_force_tbl[i];
214 
215                 if (fe->port != -1 && fe->port != link->ap->print_id)
216                         continue;
217 
218                 if (fe->device != -1 && fe->device != linkno)
219                         continue;
220 
221                 if (!fe->param.spd_limit)
222                         continue;
223 
224                 link->hw_sata_spd_limit = (1 << fe->param.spd_limit) - 1;
225                 ata_link_printk(link, KERN_NOTICE,
226                         "FORCE: PHY spd limit set to %s\n", fe->param.name);
227                 return;
228         }
229 }
230 
231 /**
232  *      ata_force_xfermask - force xfermask according to libata.force
233  *      @dev: ATA device of interest
234  *
235  *      Force xfer_mask according to libata.force and whine about it.
236  *      For consistency with link selection, device number 15 selects
237  *      the first device connected to the host link.
238  *
239  *      LOCKING:
240  *      EH context.
241  */
242 static void ata_force_xfermask(struct ata_device *dev)
243 {
244         int devno = dev->link->pmp + dev->devno;
245         int alt_devno = devno;
246         int i;
247 
248         /* allow n.15 for the first device attached to host port */
249         if (ata_is_host_link(dev->link) && devno == 0)
250                 alt_devno = 15;
251 
252         for (i = ata_force_tbl_size - 1; i >= 0; i--) {
253                 const struct ata_force_ent *fe = &ata_force_tbl[i];
254                 unsigned long pio_mask, mwdma_mask, udma_mask;
255 
256                 if (fe->port != -1 && fe->port != dev->link->ap->print_id)
257                         continue;
258 
259                 if (fe->device != -1 && fe->device != devno &&
260                     fe->device != alt_devno)
261                         continue;
262 
263                 if (!fe->param.xfer_mask)
264                         continue;
265 
266                 ata_unpack_xfermask(fe->param.xfer_mask,
267                                     &pio_mask, &mwdma_mask, &udma_mask);
268                 if (udma_mask)
269                         dev->udma_mask = udma_mask;
270                 else if (mwdma_mask) {
271                         dev->udma_mask = 0;
272                         dev->mwdma_mask = mwdma_mask;
273                 } else {
274                         dev->udma_mask = 0;
275                         dev->mwdma_mask = 0;
276                         dev->pio_mask = pio_mask;
277                 }
278 
279                 ata_dev_printk(dev, KERN_NOTICE,
280                         "FORCE: xfer_mask set to %s\n", fe->param.name);
281                 return;
282         }
283 }
284 
285 /**
286  *      ata_force_horkage - force horkage according to libata.force
287  *      @dev: ATA device of interest
288  *
289  *      Force horkage according to libata.force and whine about it.
290  *      For consistency with link selection, device number 15 selects
291  *      the first device connected to the host link.
292  *
293  *      LOCKING:
294  *      EH context.
295  */
296 static void ata_force_horkage(struct ata_device *dev)
297 {
298         int devno = dev->link->pmp + dev->devno;
299         int alt_devno = devno;
300         int i;
301 
302         /* allow n.15 for the first device attached to host port */
303         if (ata_is_host_link(dev->link) && devno == 0)
304                 alt_devno = 15;
305 
306         for (i = 0; i < ata_force_tbl_size; i++) {
307                 const struct ata_force_ent *fe = &ata_force_tbl[i];
308 
309                 if (fe->port != -1 && fe->port != dev->link->ap->print_id)
310                         continue;
311 
312                 if (fe->device != -1 && fe->device != devno &&
313                     fe->device != alt_devno)
314                         continue;
315 
316                 if (!(~dev->horkage & fe->param.horkage_on) &&
317                     !(dev->horkage & fe->param.horkage_off))
318                         continue;
319 
320                 dev->horkage |= fe->param.horkage_on;
321                 dev->horkage &= ~fe->param.horkage_off;
322 
323                 ata_dev_printk(dev, KERN_NOTICE,
324                         "FORCE: horkage modified (%s)\n", fe->param.name);
325         }
326 }
327 
328 /**
329  *      atapi_cmd_type - Determine ATAPI command type from SCSI opcode
330  *      @opcode: SCSI opcode
331  *
332  *      Determine ATAPI command type from @opcode.
333  *
334  *      LOCKING:
335  *      None.
336  *
337  *      RETURNS:
338  *      ATAPI_{READ|WRITE|READ_CD|PASS_THRU|MISC}
339  */
340 int atapi_cmd_type(u8 opcode)
341 {
342         switch (opcode) {
343         case GPCMD_READ_10:
344         case GPCMD_READ_12:
345                 return ATAPI_READ;
346 
347         case GPCMD_WRITE_10:
348         case GPCMD_WRITE_12:
349         case GPCMD_WRITE_AND_VERIFY_10:
350                 return ATAPI_WRITE;
351 
352         case GPCMD_READ_CD:
353         case GPCMD_READ_CD_MSF:
354                 return ATAPI_READ_CD;
355 
356         case ATA_16:
357         case ATA_12:
358                 if (atapi_passthru16)
359                         return ATAPI_PASS_THRU;
360                 /* fall thru */
361         default:
362                 return ATAPI_MISC;
363         }
364 }
365 
366 /**
367  *      ata_tf_to_fis - Convert ATA taskfile to SATA FIS structure
368  *      @tf: Taskfile to convert
369  *      @pmp: Port multiplier port
370  *      @is_cmd: This FIS is for command
371  *      @fis: Buffer into which data will output
372  *
373  *      Converts a standard ATA taskfile to a Serial ATA
374  *      FIS structure (Register - Host to Device).
375  *
376  *      LOCKING:
377  *      Inherited from caller.
378  */
379 void ata_tf_to_fis(const struct ata_taskfile *tf, u8 pmp, int is_cmd, u8 *fis)
380 {
381         fis[0] = 0x27;                  /* Register - Host to Device FIS */
382         fis[1] = pmp & 0xf;             /* Port multiplier number*/
383         if (is_cmd)
384                 fis[1] |= (1 << 7);     /* bit 7 indicates Command FIS */
385 
386         fis[2] = tf->command;
387         fis[3] = tf->feature;
388 
389         fis[4] = tf->lbal;
390         fis[5] = tf->lbam;
391         fis[6] = tf->lbah;
392         fis[7] = tf->device;
393 
394         fis[8] = tf->hob_lbal;
395         fis[9] = tf->hob_lbam;
396         fis[10] = tf->hob_lbah;
397         fis[11] = tf->hob_feature;
398 
399         fis[12] = tf->nsect;
400         fis[13] = tf->hob_nsect;
401         fis[14] = 0;
402         fis[15] = tf->ctl;
403 
404         fis[16] = 0;
405         fis[17] = 0;
406         fis[18] = 0;
407         fis[19] = 0;
408 }
409 
410 /**
411  *      ata_tf_from_fis - Convert SATA FIS to ATA taskfile
412  *      @fis: Buffer from which data will be input
413  *      @tf: Taskfile to output
414  *
415  *      Converts a serial ATA FIS structure to a standard ATA taskfile.
416  *
417  *      LOCKING:
418  *      Inherited from caller.
419  */
420 
421 void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf)
422 {
423         tf->command     = fis[2];       /* status */
424         tf->feature     = fis[3];       /* error */
425 
426         tf->lbal        = fis[4];
427         tf->lbam        = fis[5];
428         tf->lbah        = fis[6];
429         tf->device      = fis[7];
430 
431         tf->hob_lbal    = fis[8];
432         tf->hob_lbam    = fis[9];
433         tf->hob_lbah    = fis[10];
434 
435         tf->nsect       = fis[12];
436         tf->hob_nsect   = fis[13];
437 }
438 
439 static const u8 ata_rw_cmds[] = {
440         /* pio multi */
441         ATA_CMD_READ_MULTI,
442         ATA_CMD_WRITE_MULTI,
443         ATA_CMD_READ_MULTI_EXT,
444         ATA_CMD_WRITE_MULTI_EXT,
445         0,
446         0,
447         0,
448         ATA_CMD_WRITE_MULTI_FUA_EXT,
449         /* pio */
450         ATA_CMD_PIO_READ,
451         ATA_CMD_PIO_WRITE,
452         ATA_CMD_PIO_READ_EXT,
453         ATA_CMD_PIO_WRITE_EXT,
454         0,
455         0,
456         0,
457         0,
458         /* dma */
459         ATA_CMD_READ,
460         ATA_CMD_WRITE,
461         ATA_CMD_READ_EXT,
462         ATA_CMD_WRITE_EXT,
463         0,
464         0,
465         0,
466         ATA_CMD_WRITE_FUA_EXT
467 };
468 
469 /**
470  *      ata_rwcmd_protocol - set taskfile r/w commands and protocol
471  *      @tf: command to examine and configure
472  *      @dev: device tf belongs to
473  *
474  *      Examine the device configuration and tf->flags to calculate
475  *      the proper read/write commands and protocol to use.
476  *
477  *      LOCKING:
478  *      caller.
479  */
480 static int ata_rwcmd_protocol(struct ata_taskfile *tf, struct ata_device *dev)
481 {
482         u8 cmd;
483 
484         int index, fua, lba48, write;
485 
486         fua = (tf->flags & ATA_TFLAG_FUA) ? 4 : 0;
487         lba48 = (tf->flags & ATA_TFLAG_LBA48) ? 2 : 0;
488         write = (tf->flags & ATA_TFLAG_WRITE) ? 1 : 0;
489 
490         if (dev->flags & ATA_DFLAG_PIO) {
491                 tf->protocol = ATA_PROT_PIO;
492                 index = dev->multi_count ? 0 : 8;
493         } else if (lba48 && (dev->link->ap->flags & ATA_FLAG_PIO_LBA48)) {
494                 /* Unable to use DMA due to host limitation */
495                 tf->protocol = ATA_PROT_PIO;
496                 index = dev->multi_count ? 0 : 8;
497         } else {
498                 tf->protocol = ATA_PROT_DMA;
499                 index = 16;
500         }
501 
502         cmd = ata_rw_cmds[index + fua + lba48 + write];
503         if (cmd) {
504                 tf->command = cmd;
505                 return 0;
506         }
507         return -1;
508 }
509 
510 /**
511  *      ata_tf_read_block - Read block address from ATA taskfile
512  *      @tf: ATA taskfile of interest
513  *      @dev: ATA device @tf belongs to
514  *
515  *      LOCKING:
516  *      None.
517  *
518  *      Read block address from @tf.  This function can handle all
519  *      three address formats - LBA, LBA48 and CHS.  tf->protocol and
520  *      flags select the address format to use.
521  *
522  *      RETURNS:
523  *      Block address read from @tf.
524  */
525 u64 ata_tf_read_block(struct ata_taskfile *tf, struct ata_device *dev)
526 {
527         u64 block = 0;
528 
529         if (tf->flags & ATA_TFLAG_LBA) {
530                 if (tf->flags & ATA_TFLAG_LBA48) {
531                         block |= (u64)tf->hob_lbah << 40;
532                         block |= (u64)tf->hob_lbam << 32;
533                         block |= tf->hob_lbal << 24;
534                 } else
535                         block |= (tf->device & 0xf) << 24;
536 
537                 block |= tf->lbah << 16;
538                 block |= tf->lbam << 8;
539                 block |= tf->lbal;
540         } else {
541                 u32 cyl, head, sect;
542 
543                 cyl = tf->lbam | (tf->lbah << 8);
544                 head = tf->device & 0xf;
545                 sect = tf->lbal;
546 
547                 block = (cyl * dev->heads + head) * dev->sectors + sect;
548         }
549 
550         return block;
551 }
552 
553 /**
554  *      ata_build_rw_tf - Build ATA taskfile for given read/write request
555  *      @tf: Target ATA taskfile
556  *      @dev: ATA device @tf belongs to
557  *      @block: Block address
558  *      @n_block: Number of blocks
559  *      @tf_flags: RW/FUA etc...
560  *      @tag: tag
561  *
562  *      LOCKING:
563  *      None.
564  *
565  *      Build ATA taskfile @tf for read/write request described by
566  *      @block, @n_block, @tf_flags and @tag on @dev.
567  *
568  *      RETURNS:
569  *
570  *      0 on success, -ERANGE if the request is too large for @dev,
571  *      -EINVAL if the request is invalid.
572  */
573 int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
574                     u64 block, u32 n_block, unsigned int tf_flags,
575                     unsigned int tag)
576 {
577         tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
578         tf->flags |= tf_flags;
579 
580         if (ata_ncq_enabled(dev) && likely(tag != ATA_TAG_INTERNAL)) {
581                 /* yay, NCQ */
582                 if (!lba_48_ok(block, n_block))
583                         return -ERANGE;
584 
585                 tf->protocol = ATA_PROT_NCQ;
586                 tf->flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
587 
588                 if (tf->flags & ATA_TFLAG_WRITE)
589                         tf->command = ATA_CMD_FPDMA_WRITE;
590                 else
591                         tf->command = ATA_CMD_FPDMA_READ;
592 
593                 tf->nsect = tag << 3;
594                 tf->hob_feature = (n_block >> 8) & 0xff;
595                 tf->feature = n_block & 0xff;
596 
597                 tf->hob_lbah = (block >> 40) & 0xff;
598                 tf->hob_lbam = (block >> 32) & 0xff;
599                 tf->hob_lbal = (block >> 24) & 0xff;
600                 tf->lbah = (block >> 16) & 0xff;
601                 tf->lbam = (block >> 8) & 0xff;
602                 tf->lbal = block & 0xff;
603 
604                 tf->device = 1 << 6;
605                 if (tf->flags & ATA_TFLAG_FUA)
606                         tf->device |= 1 << 7;
607         } else if (dev->flags & ATA_DFLAG_LBA) {
608                 tf->flags |= ATA_TFLAG_LBA;
609 
610                 if (lba_28_ok(block, n_block)) {
611                         /* use LBA28 */
612                         tf->device |= (block >> 24) & 0xf;
613                 } else if (lba_48_ok(block, n_block)) {
614                         if (!(dev->flags & ATA_DFLAG_LBA48))
615                                 return -ERANGE;
616 
617                         /* use LBA48 */
618                         tf->flags |= ATA_TFLAG_LBA48;
619 
620                         tf->hob_nsect = (n_block >> 8) & 0xff;
621 
622                         tf->hob_lbah = (block >> 40) & 0xff;
623                         tf->hob_lbam = (block >> 32) & 0xff;
624                         tf->hob_lbal = (block >> 24) & 0xff;
625                 } else
626                         /* request too large even for LBA48 */
627                         return -ERANGE;
628 
629                 if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
630                         return -EINVAL;
631 
632                 tf->nsect = n_block & 0xff;
633 
634                 tf->lbah = (block >> 16) & 0xff;
635                 tf->lbam = (block >> 8) & 0xff;
636                 tf->lbal = block & 0xff;
637 
638                 tf->device |= ATA_LBA;
639         } else {
640                 /* CHS */
641                 u32 sect, head, cyl, track;
642 
643                 /* The request -may- be too large for CHS addressing. */
644                 if (!lba_28_ok(block, n_block))
645                         return -ERANGE;
646 
647                 if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
648                         return -EINVAL;
649 
650                 /* Convert LBA to CHS */
651                 track = (u32)block / dev->sectors;
652                 cyl   = track / dev->heads;
653                 head  = track % dev->heads;
654                 sect  = (u32)block % dev->sectors + 1;
655 
656                 DPRINTK("block %u track %u cyl %u head %u sect %u\n",
657                         (u32)block, track, cyl, head, sect);
658 
659                 /* Check whether the converted CHS can fit.
660                    Cylinder: 0-65535
661                    Head: 0-15
662                    Sector: 1-255*/
663                 if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
664                         return -ERANGE;
665 
666                 tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
667                 tf->lbal = sect;
668                 tf->lbam = cyl;
669                 tf->lbah = cyl >> 8;
670                 tf->device |= head;
671         }
672 
673         return 0;
674 }
675 
676 /**
677  *      ata_pack_xfermask - Pack pio, mwdma and udma masks into xfer_mask
678  *      @pio_mask: pio_mask
679  *      @mwdma_mask: mwdma_mask
680  *      @udma_mask: udma_mask
681  *
682  *      Pack @pio_mask, @mwdma_mask and @udma_mask into a single
683  *      unsigned int xfer_mask.
684  *
685  *      LOCKING:
686  *      None.
687  *
688  *      RETURNS:
689  *      Packed xfer_mask.
690  */
691 unsigned long ata_pack_xfermask(unsigned long pio_mask,
692                                 unsigned long mwdma_mask,
693                                 unsigned long udma_mask)
694 {
695         return ((pio_mask << ATA_SHIFT_PIO) & ATA_MASK_PIO) |
696                 ((mwdma_mask << ATA_SHIFT_MWDMA) & ATA_MASK_MWDMA) |
697                 ((udma_mask << ATA_SHIFT_UDMA) & ATA_MASK_UDMA);
698 }
699 
700 /**
701  *      ata_unpack_xfermask - Unpack xfer_mask into pio, mwdma and udma masks
702  *      @xfer_mask: xfer_mask to unpack
703  *      @pio_mask: resulting pio_mask
704  *      @mwdma_mask: resulting mwdma_mask
705  *      @udma_mask: resulting udma_mask
706  *
707  *      Unpack @xfer_mask into @pio_mask, @mwdma_mask and @udma_mask.
708  *      Any NULL distination masks will be ignored.
709  */
710 void ata_unpack_xfermask(unsigned long xfer_mask, unsigned long *pio_mask,
711                          unsigned long *mwdma_mask, unsigned long *udma_mask)
712 {
713         if (pio_mask)
714                 *pio_mask = (xfer_mask & ATA_MASK_PIO) >> ATA_SHIFT_PIO;
715         if (mwdma_mask)
716                 *mwdma_mask = (xfer_mask & ATA_MASK_MWDMA) >> ATA_SHIFT_MWDMA;
717         if (udma_mask)
718                 *udma_mask = (xfer_mask & ATA_MASK_UDMA) >> ATA_SHIFT_UDMA;
719 }
720 
721 static const struct ata_xfer_ent {
722         int shift, bits;
723         u8 base;
724 } ata_xfer_tbl[] = {
725         { ATA_SHIFT_PIO, ATA_NR_PIO_MODES, XFER_PIO_0 },
726         { ATA_SHIFT_MWDMA, ATA_NR_MWDMA_MODES, XFER_MW_DMA_0 },
727         { ATA_SHIFT_UDMA, ATA_NR_UDMA_MODES, XFER_UDMA_0 },
728         { -1, },
729 };
730 
731 /**
732  *      ata_xfer_mask2mode - Find matching XFER_* for the given xfer_mask
733  *      @xfer_mask: xfer_mask of interest
734  *
735  *      Return matching XFER_* value for @xfer_mask.  Only the highest
736  *      bit of @xfer_mask is considered.
737  *
738  *      LOCKING:
739  *      None.
740  *
741  *      RETURNS:
742  *      Matching XFER_* value, 0xff if no match found.
743  */
744 u8 ata_xfer_mask2mode(unsigned long xfer_mask)
745 {
746         int highbit = fls(xfer_mask) - 1;
747         const struct ata_xfer_ent *ent;
748 
749         for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
750                 if (highbit >= ent->shift && highbit < ent->shift + ent->bits)
751                         return ent->base + highbit - ent->shift;
752         return 0xff;
753 }
754 
755 /**
756  *      ata_xfer_mode2mask - Find matching xfer_mask for XFER_*
757  *      @xfer_mode: XFER_* of interest
758  *
759  *      Return matching xfer_mask for @xfer_mode.
760  *
761  *      LOCKING:
762  *      None.
763  *
764  *      RETURNS:
765  *      Matching xfer_mask, 0 if no match found.
766  */
767 unsigned long ata_xfer_mode2mask(u8 xfer_mode)
768 {
769         const struct ata_xfer_ent *ent;
770 
771         for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
772                 if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
773                         return ((2 << (ent->shift + xfer_mode - ent->base)) - 1)
774                                 & ~((1 << ent->shift) - 1);
775         return 0;
776 }
777 
778 /**
779  *      ata_xfer_mode2shift - Find matching xfer_shift for XFER_*
780  *      @xfer_mode: XFER_* of interest
781  *
782  *      Return matching xfer_shift for @xfer_mode.
783  *
784  *      LOCKING:
785  *      None.
786  *
787  *      RETURNS:
788  *      Matching xfer_shift, -1 if no match found.
789  */
790 int ata_xfer_mode2shift(unsigned long xfer_mode)
791 {
792         const struct ata_xfer_ent *ent;
793 
794         for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
795                 if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
796                         return ent->shift;
797         return -1;
798 }
799 
800 /**
801  *      ata_mode_string - convert xfer_mask to string
802  *      @xfer_mask: mask of bits supported; only highest bit counts.
803  *
804  *      Determine string which represents the highest speed
805  *      (highest bit in @modemask).
806  *
807  *      LOCKING:
808  *      None.
809  *
810  *      RETURNS:
811  *      Constant C string representing highest speed listed in
812  *      @mode_mask, or the constant C string "<n/a>".
813  */
814 const char *ata_mode_string(unsigned long xfer_mask)
815 {
816         static const char * const xfer_mode_str[] = {
817                 "PIO0",
818                 "PIO1",
819                 "PIO2",
820                 "PIO3",
821                 "PIO4",
822                 "PIO5",
823                 "PIO6",
824                 "MWDMA0",
825                 "MWDMA1",
826                 "MWDMA2",
827                 "MWDMA3",
828                 "MWDMA4",
829                 "UDMA/16",
830                 "UDMA/25",
831                 "UDMA/33",
832                 "UDMA/44",
833                 "UDMA/66",
834                 "UDMA/100",
835                 "UDMA/133",
836                 "UDMA7",
837         };
838         int highbit;
839 
840         highbit = fls(xfer_mask) - 1;
841         if (highbit >= 0 && highbit < ARRAY_SIZE(xfer_mode_str))
842                 return xfer_mode_str[highbit];
843         return "<n/a>";
844 }
845 
846 static const char *sata_spd_string(unsigned int spd)
847 {
848         static const char * const spd_str[] = {
849                 "1.5 Gbps",
850                 "3.0 Gbps",
851         };
852 
853         if (spd == 0 || (spd - 1) >= ARRAY_SIZE(spd_str))
854                 return "<unknown>";
855         return spd_str[spd - 1];
856 }
857 
858 void ata_dev_disable(struct ata_device *dev)
859 {
860         if (ata_dev_enabled(dev)) {
861                 if (ata_msg_drv(dev->link->ap))
862                         ata_dev_printk(dev, KERN_WARNING, "disabled\n");
863                 ata_acpi_on_disable(dev);
864                 ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO0 |
865                                              ATA_DNXFER_QUIET);
866                 dev->class++;
867         }
868 }
869 
870 static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
871 {
872         struct ata_link *link = dev->link;
873         struct ata_port *ap = link->ap;
874         u32 scontrol;
875         unsigned int err_mask;
876         int rc;
877 
878         /*
879          * disallow DIPM for drivers which haven't set
880          * ATA_FLAG_IPM.  This is because when DIPM is enabled,
881          * phy ready will be set in the interrupt status on
882          * state changes, which will cause some drivers to
883          * think there are errors - additionally drivers will
884          * need to disable hot plug.
885          */
886         if (!(ap->flags & ATA_FLAG_IPM) || !ata_dev_enabled(dev)) {
887                 ap->pm_policy = NOT_AVAILABLE;
888                 return -EINVAL;
889         }
890 
891         /*
892          * For DIPM, we will only enable it for the
893          * min_power setting.
894          *
895          * Why?  Because Disks are too stupid to know that
896          * If the host rejects a request to go to SLUMBER
897          * they should retry at PARTIAL, and instead it
898          * just would give up.  So, for medium_power to
899          * work at all, we need to only allow HIPM.
900          */
901         rc = sata_scr_read(link, SCR_CONTROL, &scontrol);
902         if (rc)
903                 return rc;
904 
905         switch (policy) {
906         case MIN_POWER:
907                 /* no restrictions on IPM transitions */
908                 scontrol &= ~(0x3 << 8);
909                 rc = sata_scr_write(link, SCR_CONTROL, scontrol);
910                 if (rc)
911                         return rc;
912 
913                 /* enable DIPM */
914                 if (dev->flags & ATA_DFLAG_DIPM)
915                         err_mask = ata_dev_set_feature(dev,
916                                         SETFEATURES_SATA_ENABLE, SATA_DIPM);
917                 break;
918         case MEDIUM_POWER:
919                 /* allow IPM to PARTIAL */
920                 scontrol &= ~(0x1 << 8);
921                 scontrol |= (0x2 << 8);
922                 rc = sata_scr_write(link, SCR_CONTROL, scontrol);
923                 if (rc)
924                         return rc;
925 
926                 /*
927                  * we don't have to disable DIPM since IPM flags
928                  * disallow transitions to SLUMBER, which effectively
929                  * disable DIPM if it does not support PARTIAL
930                  */
931                 break;
932         case NOT_AVAILABLE:
933         case MAX_PERFORMANCE:
934                 /* disable all IPM transitions */
935                 scontrol |= (0x3 << 8);
936                 rc = sata_scr_write(link, SCR_CONTROL, scontrol);
937                 if (rc)
938                         return rc;
939 
940                 /*
941                  * we don't have to disable DIPM since IPM flags
942                  * disallow all transitions which effectively
943                  * disable DIPM anyway.
944                  */
945                 break;
946         }
947 
948         /* FIXME: handle SET FEATURES failure */
949         (void) err_mask;
950 
951         return 0;
952 }
953 
954 /**
955  *      ata_dev_enable_pm - enable SATA interface power management
956  *      @dev:  device to enable power management
957  *      @policy: the link power management policy
958  *
959  *      Enable SATA Interface power management.  This will enable
960  *      Device Interface Power Management (DIPM) for min_power
961  *      policy, and then call driver specific callbacks for
962  *      enabling Host Initiated Power management.
963  *
964  *      Locking: Caller.
965  *      Returns: -EINVAL if IPM is not supported, 0 otherwise.
966  */
967 void ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy)
968 {
969         int rc = 0;
970         struct ata_port *ap = dev->link->ap;
971 
972         /* set HIPM first, then DIPM */
973         if (ap->ops->enable_pm)
974                 rc = ap->ops->enable_pm(ap, policy);
975         if (rc)
976                 goto enable_pm_out;
977         rc = ata_dev_set_dipm(dev, policy);
978 
979 enable_pm_out:
980         if (rc)
981                 ap->pm_policy = MAX_PERFORMANCE;
982         else
983                 ap->pm_policy = policy;
984         return /* rc */;        /* hopefully we can use 'rc' eventually */
985 }
986 
987 #ifdef CONFIG_PM
988 /**
989  *      ata_dev_disable_pm - disable SATA interface power management
990  *      @dev: device to disable power management
991  *
992  *      Disable SATA Interface power management.  This will disable
993  *      Device Interface Power Management (DIPM) without changing
994  *      policy,  call driver specific callbacks for disabling Host
995  *      Initiated Power management.
996  *
997  *      Locking: Caller.
998  *      Returns: void
999  */
1000 static void ata_dev_disable_pm(struct ata_device *dev)
1001 {
1002         struct ata_port *ap = dev->link->ap;
1003 
1004         ata_dev_set_dipm(dev, MAX_PERFORMANCE);
1005         if (ap->ops->disable_pm)
1006                 ap->ops->disable_pm(ap);
1007 }
1008 #endif  /* CONFIG_PM */
1009 
1010 void ata_lpm_schedule(struct ata_port *ap, enum link_pm policy)
1011 {
1012         ap->pm_policy = policy;
1013         ap->link.eh_info.action |= ATA_EH_LPM;
1014         ap->link.eh_info.flags |= ATA_EHI_NO_AUTOPSY;
1015         ata_port_schedule_eh(ap);
1016 }
1017 
1018 #ifdef CONFIG_PM
1019 static void ata_lpm_enable(struct ata_host *host)
1020 {
1021         struct ata_link *link;
1022         struct ata_port *ap;
1023         struct ata_device *dev;
1024         int i;
1025 
1026         for (i = 0; i < host->n_ports; i++) {
1027                 ap = host->ports[i];
1028                 ata_port_for_each_link(link, ap) {
1029                         ata_link_for_each_dev(dev, link)
1030                                 ata_dev_disable_pm(dev);
1031                 }
1032         }
1033 }
1034 
1035 static void ata_lpm_disable(struct ata_host *host)
1036 {
1037         int i;
1038 
1039         for (i = 0; i < host->n_ports; i++) {
1040                 struct ata_port *ap = host->ports[i];
1041                 ata_lpm_schedule(ap, ap->pm_policy);
1042         }
1043 }
1044 #endif  /* CONFIG_PM */
1045 
1046 
1047 /**
1048  *      ata_devchk - PATA device presence detection
1049  *      @ap: ATA channel to examine
1050  *      @device: Device to examine (starting at zero)
1051  *
1052  *      This technique was originally described in
1053  *      Hale Landis's ATADRVR (www.ata-atapi.com), and
1054  *      later found its way into the ATA/ATAPI spec.
1055  *
1056  *      Write a pattern to the ATA shadow registers,
1057  *      and if a device is present, it will respond by
1058  *      correctly storing and echoing back the
1059  *      ATA shadow register contents.
1060  *
1061  *      LOCKING:
1062  *      caller.
1063  */
1064 
1065 static unsigned int ata_devchk(struct ata_port *ap, unsigned int device)
1066 {
1067         struct ata_ioports *ioaddr = &ap->ioaddr;
1068         u8 nsect, lbal;
1069 
1070         ap->ops->dev_select(ap, device);
1071 
1072         iowrite8(0x55, ioaddr->nsect_addr);
1073         iowrite8(0xaa, ioaddr->lbal_addr);
1074 
1075         iowrite8(0xaa, ioaddr->nsect_addr);
1076         iowrite8(0x55, ioaddr->lbal_addr);
1077 
1078         iowrite8(0x55, ioaddr->nsect_addr);
1079         iowrite8(0xaa, ioaddr->lbal_addr);
1080 
1081         nsect = ioread8(ioaddr->nsect_addr);
1082         lbal = ioread8(ioaddr->lbal_addr);
1083 
1084         if ((nsect == 0x55) && (lbal == 0xaa))
1085                 return 1;       /* we found a device */
1086 
1087         return 0;               /* nothing found */
1088 }
1089 
1090 /**
1091  *      ata_dev_classify - determine device type based on ATA-spec signature
1092  *      @tf: ATA taskfile register set for device to be identified
1093  *
1094  *      Determine from taskfile register contents whether a device is
1095  *      ATA or ATAPI, as per "Signature and persistence" section
1096  *      of ATA/PI spec (volume 1, sect 5.14).
1097  *
1098  *      LOCKING:
1099  *      None.
1100  *
1101  *      RETURNS:
1102  *      Device type, %ATA_DEV_ATA, %ATA_DEV_ATAPI, %ATA_DEV_PMP or
1103  *      %ATA_DEV_UNKNOWN the event of failure.
1104  */
1105 unsigned int ata_dev_classify(const struct ata_taskfile *tf)
1106 {
1107         /* Apple's open source Darwin code hints that some devices only
1108          * put a proper signature into the LBA mid/high registers,
1109          * So, we only check those.  It's sufficient for uniqueness.
1110          *
1111          * ATA/ATAPI-7 (d1532v1r1: Feb. 19, 2003) specified separate
1112          * signatures for ATA and ATAPI devices attached on SerialATA,
1113          * 0x3c/0xc3 and 0x69/0x96 respectively.  However, SerialATA
1114          * spec has never mentioned about using different signatures
1115          * for ATA/ATAPI devices.  Then, Serial ATA II: Port
1116          * Multiplier specification began to use 0x69/0x96 to identify
1117          * port multpliers and 0x3c/0xc3 to identify SEMB device.
1118          * ATA/ATAPI-7 dropped descriptions about 0x3c/0xc3 and
1119          * 0x69/0x96 shortly and described them as reserved for
1120          * SerialATA.
1121          *
1122          * We follow the current spec and consider that 0x69/0x96
1123          * identifies a port multiplier and 0x3c/0xc3 a SEMB device.
1124          */
1125         if ((tf->lbam == 0) && (tf->lbah == 0)) {
1126                 DPRINTK("found ATA device by sig\n");
1127                 return ATA_DEV_ATA;
1128         }
1129 
1130         if ((tf->lbam == 0x14) && (tf->lbah == 0xeb)) {
1131                 DPRINTK("found ATAPI device by sig\n");
1132                 return ATA_DEV_ATAPI;
1133         }
1134 
1135         if ((tf->lbam == 0x69) && (tf->lbah == 0x96)) {
1136                 DPRINTK("found PMP device by sig\n");
1137                 return ATA_DEV_PMP;
1138         }
1139 
1140         if ((tf->lbam == 0x3c) && (tf->lbah == 0xc3)) {
1141                 printk(KERN_INFO "ata: SEMB device ignored\n");
1142                 return ATA_DEV_SEMB_UNSUP; /* not yet */
1143         }
1144 
1145         DPRINTK("unknown device\n");
1146         return ATA_DEV_UNKNOWN;
1147 }
1148 
1149 /**
1150  *      ata_dev_try_classify - Parse returned ATA device signature
1151  *      @dev: ATA device to classify (starting at zero)
1152  *      @present: device seems present
1153  *      @r_err: Value of error register on completion
1154  *
1155  *      After an event -- SRST, E.D.D., or SATA COMRESET -- occurs,
1156  *      an ATA/ATAPI-defined set of values is placed in the ATA
1157  *      shadow registers, indicating the results of device detection
1158  *      and diagnostics.
1159  *
1160  *      Select the ATA device, and read the values from the ATA shadow
1161  *      registers.  Then parse according to the Error register value,
1162  *      and the spec-defined values examined by ata_dev_classify().
1163  *
1164  *      LOCKING:
1165  *      caller.
1166  *
1167  *      RETURNS:
1168  *      Device type - %ATA_DEV_ATA, %ATA_DEV_ATAPI or %ATA_DEV_NONE.
1169  */
1170 unsigned int ata_dev_try_classify(struct ata_device *dev, int present,
1171                                   u8 *r_err)
1172 {
1173         struct ata_port *ap = dev->link->ap;
1174         struct ata_taskfile tf;
1175         unsigned int class;
1176         u8 err;
1177 
1178         ap->ops->dev_select(ap, dev->devno);
1179 
1180         memset(&tf, 0, sizeof(tf));
1181 
1182         ap->ops->tf_read(ap, &tf);
1183         err = tf.feature;
1184         if (r_err)
1185                 *r_err = err;
1186 
1187         /* see if device passed diags: continue and warn later */
1188         if (err == 0)
1189                 /* diagnostic fail : do nothing _YET_ */
1190                 dev->horkage |= ATA_HORKAGE_DIAGNOSTIC;
1191         else if (err == 1)
1192                 /* do nothing */ ;
1193         else if ((dev->devno == 0) && (err == 0x81))
1194                 /* do nothing */ ;
1195         else
1196                 return ATA_DEV_NONE;
1197 
1198         /* determine if device is ATA or ATAPI */
1199         class = ata_dev_classify(&tf);
1200 
1201         if (class == ATA_DEV_UNKNOWN) {
1202                 /* If the device failed diagnostic, it's likely to
1203                  * have reported incorrect device signature too.
1204                  * Assume ATA device if the device seems present but
1205                  * device signature is invalid with diagnostic
1206                  * failure.
1207                  */
1208                 if (present && (dev->horkage & ATA_HORKAGE_DIAGNOSTIC))
1209                         class = ATA_DEV_ATA;
1210                 else
1211                         class = ATA_DEV_NONE;
1212         } else if ((class == ATA_DEV_ATA) && (ata_chk_status(ap) == 0))
1213                 class = ATA_DEV_NONE;
1214 
1215         return class;
1216 }
1217 
1218 /**
1219  *      ata_id_string - Convert IDENTIFY DEVICE page into string
1220  *      @id: IDENTIFY DEVICE results we will examine
1221  *      @s: string into which data is output
1222  *      @ofs: offset into identify device page
1223  *      @len: length of string to return. must be an even number.
1224  *
1225  *      The strings in the IDENTIFY DEVICE page are broken up into
1226  *      16-bit chunks.  Run through the string, and output each
1227  *      8-bit chunk linearly, regardless of platform.
1228  *
1229  *      LOCKING:
1230  *      caller.
1231  */
1232 
1233 void ata_id_string(const u16 *id, unsigned char *s,
1234                    unsigned int ofs, unsigned int len)
1235 {
1236         unsigned int c;
1237 
1238         while (len > 0) {
1239                 c = id[ofs] >> 8;
1240                 *s = c;
1241                 s++;
1242 
1243                 c = id[ofs] & 0xff;
1244                 *s = c;
1245                 s++;
1246 
1247                 ofs++;
1248                 len -= 2;
1249         }
1250 }
1251 
1252 /**
1253  *      ata_id_c_string - Convert IDENTIFY DEVICE page into C string
1254  *      @id: IDENTIFY DEVICE results we will examine
1255  *      @s: string into which data is output
1256  *      @ofs: offset into identify device page
1257  *      @len: length of string to return. must be an odd number.
1258  *
1259  *      This function is identical to ata_id_string except that it
1260  *      trims trailing spaces and terminates the resulting string with
1261  *      null.  @len must be actual maximum length (even number) + 1.
1262  *
1263  *      LOCKING:
1264  *      caller.
1265  */
1266 void ata_id_c_string(const u16 *id, unsigned char *s,
1267                      unsigned int ofs, unsigned int len)
1268 {
1269         unsigned char *p;
1270 
1271         WARN_ON(!(len & 1));
1272 
1273         ata_id_string(id, s, ofs, len - 1);
1274 
1275         p = s + strnlen(s, len - 1);
1276         while (p > s && p[-1] == ' ')
1277                 p--;
1278         *p = '\0';
1279 }
1280 
1281 static u64 ata_id_n_sectors(const u16 *id)
1282 {
1283         if (ata_id_has_lba(id)) {
1284                 if (ata_id_has_lba48(id))
1285                         return ata_id_u64(id, 100);
1286                 else
1287                         return ata_id_u32(id, 60);
1288         } else {
1289                 if (ata_id_current_chs_valid(id))
1290                         return ata_id_u32(id, 57);
1291                 else
1292                         return id[1] * id[3] * id[6];
1293         }
1294 }
1295 
1296 static u64 ata_tf_to_lba48(struct ata_taskfile *tf)
1297 {
1298         u64 sectors = 0;
1299 
1300         sectors |= ((u64)(tf->hob_lbah & 0xff)) << 40;
1301         sectors |= ((u64)(tf->hob_lbam & 0xff)) << 32;
1302         sectors |= (tf->hob_lbal & 0xff) << 24;
1303         sectors |= (tf->lbah & 0xff) << 16;
1304         sectors |= (tf->lbam & 0xff) << 8;
1305         sectors |= (tf->lbal & 0xff);
1306 
1307         return ++sectors;
1308 }
1309 
1310 static u64 ata_tf_to_lba(struct ata_taskfile *tf)
1311 {
1312         u64 sectors = 0;
1313 
1314         sectors |= (tf->device & 0x0f) << 24;
1315         sectors |= (tf->lbah & 0xff) << 16;
1316         sectors |= (tf->lbam & 0xff) << 8;
1317         sectors |= (tf->lbal & 0xff);
1318 
1319         return ++sectors;
1320 }
1321 
1322 /**
1323  *      ata_read_native_max_address - Read native max address
1324  *      @dev: target device
1325  *      @max_sectors: out parameter for the result native max address
1326  *
1327  *      Perform an LBA48 or LBA28 native size query upon the device in
1328  *      question.
1329  *
1330  *      RETURNS:
1331  *      0 on success, -EACCES if command is aborted by the drive.
1332  *      -EIO on other errors.
1333  */
1334 static int ata_read_native_max_address(struct ata_device *dev, u64 *max_sectors)
1335 {
1336         unsigned int err_mask;
1337         struct ata_taskfile tf;
1338         int lba48 = ata_id_has_lba48(dev->id);
1339 
1340         ata_tf_init(dev, &tf);
1341 
1342         /* always clear all address registers */
1343         tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1344 
1345         if (lba48) {
1346                 tf.command = ATA_CMD_READ_NATIVE_MAX_EXT;
1347                 tf.flags |= ATA_TFLAG_LBA48;
1348         } else
1349                 tf.command = ATA_CMD_READ_NATIVE_MAX;
1350 
1351         tf.protocol |= ATA_PROT_NODATA;
1352         tf.device |= ATA_LBA;
1353 
1354         err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1355         if (err_mask) {
1356                 ata_dev_printk(dev, KERN_WARNING, "failed to read native "
1357                                "max address (err_mask=0x%x)\n", err_mask);
1358                 if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
1359                         return -EACCES;
1360                 return -EIO;
1361         }
1362 
1363         if (lba48)
1364                 *max_sectors = ata_tf_to_lba48(&tf);
1365         else
1366                 *max_sectors = ata_tf_to_lba(&tf);
1367         if (dev->horkage & ATA_HORKAGE_HPA_SIZE)
1368                 (*max_sectors)--;
1369         return 0;
1370 }
1371 
1372 /**
1373  *      ata_set_max_sectors - Set max sectors
1374  *      @dev: target device
1375  *      @new_sectors: new max sectors value to set for the device
1376  *
1377  *      Set max sectors of @dev to @new_sectors.
1378  *
1379  *      RETURNS:
1380  *      0 on success, -EACCES if command is aborted or denied (due to
1381  *      previous non-volatile SET_MAX) by the drive.  -EIO on other
1382  *      errors.
1383  */
1384 static int ata_set_max_sectors(struct ata_device *dev, u64 new_sectors)
1385 {
1386         unsigned int err_mask;
1387         struct ata_taskfile tf;
1388         int lba48 = ata_id_has_lba48(dev->id);
1389 
1390         new_sectors--;
1391 
1392         ata_tf_init(dev, &tf);
1393 
1394         tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1395 
1396         if (lba48) {
1397                 tf.command = ATA_CMD_SET_MAX_EXT;
1398                 tf.flags |= ATA_TFLAG_LBA48;
1399 
1400                 tf.hob_lbal = (new_sectors >> 24) & 0xff;
1401                 tf.hob_lbam = (new_sectors >> 32) & 0xff;
1402                 tf.hob_lbah = (new_sectors >> 40) & 0xff;
1403         } else {
1404                 tf.command = ATA_CMD_SET_MAX;
1405 
1406                 tf.device |= (new_sectors >> 24) & 0xf;
1407         }
1408 
1409         tf.protocol |= ATA_PROT_NODATA;
1410         tf.device |= ATA_LBA;
1411 
1412         tf.lbal = (new_sectors >> 0) & 0xff;
1413         tf.lbam = (new_sectors >> 8) & 0xff;
1414         tf.lbah = (new_sectors >> 16) & 0xff;
1415 
1416         err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1417         if (err_mask) {
1418                 ata_dev_printk(dev, KERN_WARNING, "failed to set "
1419                                "max address (err_mask=0x%x)\n", err_mask);
1420                 if (err_mask == AC_ERR_DEV &&
1421                     (tf.feature & (ATA_ABORTED | ATA_IDNF)))
1422                         return -EACCES;
1423                 return -EIO;
1424         }
1425 
1426         return 0;
1427 }
1428 
1429 /**
1430  *      ata_hpa_resize          -       Resize a device with an HPA set
1431  *      @dev: Device to resize
1432  *
1433  *      Read the size of an LBA28 or LBA48 disk with HPA features and resize
1434  *      it if required to the full size of the media. The caller must check
1435  *      the drive has the HPA feature set enabled.
1436  *
1437  *      RETURNS:
1438  *      0 on success, -errno on failure.
1439  */
1440 static int ata_hpa_resize(struct ata_device *dev)
1441 {
1442         struct ata_eh_context *ehc = &dev->link->eh_context;
1443         int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
1444         u64 sectors = ata_id_n_sectors(dev->id);
1445         u64 native_sectors;
1446         int rc;
1447 
1448         /* do we need to do it? */
1449         if (dev->class != ATA_DEV_ATA ||
1450             !ata_id_has_lba(dev->id) || !ata_id_hpa_enabled(dev->id) ||
1451             (dev->horkage & ATA_HORKAGE_BROKEN_HPA))
1452                 return 0;
1453 
1454         /* read native max address */
1455         rc = ata_read_native_max_address(dev, &native_sectors);
1456         if (rc) {
1457                 /* If device aborted the command or HPA isn't going to
1458                  * be unlocked, skip HPA resizing.
1459                  */
1460                 if (rc == -EACCES || !ata_ignore_hpa) {
1461                         ata_dev_printk(dev, KERN_WARNING, "HPA support seems "
1462                                        "broken, skipping HPA handling\n");
1463                         dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1464 
1465                         /* we can continue if device aborted the command */
1466                         if (rc == -EACCES)
1467                                 rc = 0;
1468                 }
1469 
1470                 return rc;
1471         }
1472 
1473         /* nothing to do? */
1474         if (native_sectors <= sectors || !ata_ignore_hpa) {
1475                 if (!print_info || native_sectors == sectors)
1476                         return 0;
1477 
1478                 if (native_sectors > sectors)
1479                         ata_dev_printk(dev, KERN_INFO,
1480                                 "HPA detected: current %llu, native %llu\n",
1481                                 (unsigned long long)sectors,
1482                                 (unsigned long long)native_sectors);
1483                 else if (native_sectors < sectors)
1484                         ata_dev_printk(dev, KERN_WARNING,
1485                                 "native sectors (%llu) is smaller than "
1486                                 "sectors (%llu)\n",
1487                                 (unsigned long long)native_sectors,
1488                                 (unsigned long long)sectors);
1489                 return 0;
1490         }
1491 
1492         /* let's unlock HPA */
1493         rc = ata_set_max_sectors(dev, native_sectors);
1494         if (rc == -EACCES) {
1495                 /* if device aborted the command, skip HPA resizing */
1496                 ata_dev_printk(dev, KERN_WARNING, "device aborted resize "
1497                                "(%llu -> %llu), skipping HPA handling\n",
1498                                (unsigned long long)sectors,
1499                                (unsigned long long)native_sectors);
1500                 dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1501                 return 0;
1502         } else if (rc)
1503                 return rc;
1504 
1505         /* re-read IDENTIFY data */
1506         rc = ata_dev_reread_id(dev, 0);
1507         if (rc) {
1508                 ata_dev_printk(dev, KERN_ERR, "failed to re-read IDENTIFY "
1509                                "data after HPA resizing\n");
1510                 return rc;
1511         }
1512 
1513         if (print_info) {
1514                 u64 new_sectors = ata_id_n_sectors(dev->id);
1515                 ata_dev_printk(dev, KERN_INFO,
1516                         "HPA unlocked: %llu -> %llu, native %llu\n",
1517                         (unsigned long long)sectors,
1518                         (unsigned long long)new_sectors,
1519                         (unsigned long long)native_sectors);
1520         }
1521 
1522         return 0;
1523 }
1524 
1525 /**
1526  *      ata_noop_dev_select - Select device 0/1 on ATA bus
1527  *      @ap: ATA channel to manipulate
1528  *      @device: ATA device (numbered from zero) to select
1529  *
1530  *      This function performs no actual function.
1531  *
1532  *      May be used as the dev_select() entry in ata_port_operations.
1533  *
1534  *      LOCKING:
1535  *      caller.
1536  */
1537 void ata_noop_dev_select(struct ata_port *ap, unsigned int device)
1538 {
1539 }
1540 
1541 
1542 /**
1543  *      ata_std_dev_select - Select device 0/1 on ATA bus
1544  *      @ap: ATA channel to manipulate
1545  *      @device: ATA device (numbered from zero) to select
1546  *
1547  *      Use the method defined in the ATA specification to
1548  *      make either device 0, or device 1, active on the
1549  *      ATA channel.  Works with both PIO and MMIO.
1550  *
1551  *      May be used as the dev_select() entry in ata_port_operations.
1552  *
1553  *      LOCKING:
1554  *      caller.
1555  */
1556 
1557 void ata_std_dev_select(struct ata_port *ap, unsigned int device)
1558 {
1559         u8 tmp;
1560 
1561         if (device == 0)
1562                 tmp = ATA_DEVICE_OBS;
1563         else
1564                 tmp = ATA_DEVICE_OBS | ATA_DEV1;
1565 
1566         iowrite8(tmp, ap->ioaddr.device_addr);
1567         ata_pause(ap);          /* needed; also flushes, for mmio */
1568 }
1569 
1570 /**
1571  *      ata_dev_select - Select device 0/1 on ATA bus
1572  *      @ap: ATA channel to manipulate
1573  *      @device: ATA device (numbered from zero) to select
1574  *      @wait: non-zero to wait for Status register BSY bit to clear
1575  *      @can_sleep: non-zero if context allows sleeping
1576  *
1577  *      Use the method defined in the ATA specification to
1578  *      make either device 0, or device 1, active on the
1579  *      ATA channel.
1580  *
1581  *      This is a high-level version of ata_std_dev_select(),
1582  *      which additionally provides the services of inserting
1583  *      the proper pauses and status polling, where needed.
1584  *
1585  *      LOCKING:
1586  *      caller.
1587  */
1588 
1589 void ata_dev_select(struct ata_port *ap, unsigned int device,
1590                            unsigned int wait, unsigned int can_sleep)
1591 {
1592         if (ata_msg_probe(ap))
1593                 ata_port_printk(ap, KERN_INFO, "ata_dev_select: ENTER, "
1594                                 "device %u, wait %u\n", device, wait);
1595 
1596         if (wait)
1597                 ata_wait_idle(ap);
1598 
1599         ap->ops->dev_select(ap, device);
1600 
1601         if (wait) {
1602                 if (can_sleep && ap->link.device[device].class == ATA_DEV_ATAPI)
1603                         msleep(150);
1604                 ata_wait_idle(ap);
1605         }
1606 }
1607 
1608 /**
1609  *      ata_dump_id - IDENTIFY DEVICE info debugging output
1610  *      @id: IDENTIFY DEVICE page to dump
1611  *
1612  *      Dump selected 16-bit words from the given IDENTIFY DEVICE
1613  *      page.
1614  *
1615  *      LOCKING:
1616  *      caller.
1617  */
1618 
1619 static inline void ata_dump_id(const u16 *id)
1620 {
1621         DPRINTK("49==0x%04x  "
1622                 "53==0x%04x  "
1623                 "63==0x%04x  "
1624                 "64==0x%04x  "
1625                 "75==0x%04x  \n",
1626                 id[49],
1627                 id[53],
1628                 id[63],
1629                 id[64],
1630                 id[75]);
1631         DPRINTK("80==0x%04x  "
1632                 "81==0x%04x  "
1633                 "82==0x%04x  "
1634                 "83==0x%04x  "
1635                 "84==0x%04x  \n",
1636                 id[80],
1637                 id[81],
1638                 id[82],
1639                 id[83],
1640                 id[84]);
1641         DPRINTK("88==0x%04x  "
1642                 "93==0x%04x\n",
1643                 id[88],
1644                 id[93]);
1645 }
1646 
1647 /**
1648  *      ata_id_xfermask - Compute xfermask from the given IDENTIFY data
1649  *      @id: IDENTIFY data to compute xfer mask from
1650  *
1651  *      Compute the xfermask for this device. This is not as trivial
1652  *      as it seems if we must consider early devices correctly.
1653  *
1654  *      FIXME: pre IDE drive timing (do we care ?).
1655  *
1656  *      LOCKING:
1657  *      None.
1658  *
1659  *      RETURNS:
1660  *      Computed xfermask
1661  */
1662 unsigned long ata_id_xfermask(const u16 *id)
1663 {
1664         unsigned long pio_mask, mwdma_mask, udma_mask;
1665 
1666         /* Usual case. Word 53 indicates word 64 is valid */
1667         if (id[ATA_ID_FIELD_VALID] & (1 << 1)) {
1668                 pio_mask = id[ATA_ID_PIO_MODES] & 0x03;
1669                 pio_mask <<= 3;
1670                 pio_mask |= 0x7;
1671         } else {
1672                 /* If word 64 isn't valid then Word 51 high byte holds
1673                  * the PIO timing number for the maximum. Turn it into
1674                  * a mask.
1675                  */
1676                 u8 mode = (id[ATA_ID_OLD_PIO_MODES] >> 8) & 0xFF;
1677                 if (mode < 5)   /* Valid PIO range */
1678                         pio_mask = (2 << mode) - 1;
1679                 else
1680                         pio_mask = 1;
1681 
1682                 /* But wait.. there's more. Design your standards by
1683                  * committee and you too can get a free iordy field to
1684                  * process. However its the speeds not the modes that
1685                  * are supported... Note drivers using the timing API
1686                  * will get this right anyway
1687                  */
1688         }
1689 
1690         mwdma_mask = id[ATA_ID_MWDMA_MODES] & 0x07;
1691 
1692         if (ata_id_is_cfa(id)) {
1693                 /*
1694                  *      Process compact flash extended modes
1695                  */
1696                 int pio = id[163] & 0x7;
1697                 int dma = (id[163] >> 3) & 7;
1698 
1699                 if (pio)
1700                         pio_mask |= (1 << 5);
1701                 if (pio > 1)
1702                         pio_mask |= (1 << 6);
1703                 if (dma)
1704                         mwdma_mask |= (1 << 3);
1705                 if (dma > 1)
1706                         mwdma_mask |= (1 << 4);
1707         }
1708 
1709         udma_mask = 0;
1710         if (id[ATA_ID_FIELD_VALID] & (1 << 2))
1711                 udma_mask = id[ATA_ID_UDMA_MODES] & 0xff;
1712 
1713         return ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
1714 }
1715 
1716 /**
1717  *      ata_pio_queue_task - Queue port_task
1718  *      @ap: The ata_port to queue port_task for
1719  *      @fn: workqueue function to be scheduled
1720  *      @data: data for @fn to use
1721  *      @delay: delay time for workqueue function
1722  *
1723  *      Schedule @fn(@data) for execution after @delay jiffies using
1724  *      port_task.  There is one port_task per port and it's the
1725  *      user(low level driver)'s responsibility to make sure that only
1726  *      one task is active at any given time.
1727  *
1728  *      libata core layer takes care of synchronization between
1729  *      port_task and EH.  ata_pio_queue_task() may be ignored for EH
1730  *      synchronization.
1731  *
1732  *      LOCKING:
1733  *      Inherited from caller.
1734  */
1735 static void ata_pio_queue_task(struct ata_port *ap, void *data,
1736                                unsigned long delay)
1737 {
1738         ap->port_task_data = data;
1739 
1740         /* may fail if ata_port_flush_task() in progress */
1741         queue_delayed_work(ata_wq, &ap->port_task, delay);
1742 }
1743 
1744 /**
1745  *      ata_port_flush_task - Flush port_task
1746  *      @ap: The ata_port to flush port_task for
1747  *
1748  *      After this function completes, port_task is guranteed not to
1749  *      be running or scheduled.
1750  *
1751  *      LOCKING:
1752  *      Kernel thread context (may sleep)
1753  */
1754 void ata_port_flush_task(struct ata_port *ap)
1755 {
1756         DPRINTK("ENTER\n");
1757 
1758         cancel_rearming_delayed_work(&ap->port_task);
1759 
1760         if (ata_msg_ctl(ap))
1761                 ata_port_printk(ap, KERN_DEBUG, "%s: EXIT\n", __func__);
1762 }
1763 
1764 static void ata_qc_complete_internal(struct ata_queued_cmd *qc)
1765 {
1766         struct completion *waiting = qc->private_data;
1767 
1768         complete(waiting);
1769 }
1770 
1771 /**
1772  *      ata_exec_internal_sg - execute libata internal command
1773  *      @dev: Device to which the command is sent
1774  *      @tf: Taskfile registers for the command and the result
1775  *      @cdb: CDB for packet command
1776  *      @dma_dir: Data tranfer direction of the command
1777  *      @sgl: sg list for the data buffer of the command
1778  *      @n_elem: Number of sg entries
1779  *      @timeout: Timeout in msecs (0 for default)
1780  *
1781  *      Executes libata internal command with timeout.  @tf contains
1782  *      command on entry and result on return.  Timeout and error
1783  *      conditions are reported via return value.  No recovery action
1784  *      is taken after a command times out.  It's caller's duty to
1785  *      clean up after timeout.
1786  *
1787  *      LOCKING:
1788  *      None.  Should be called with kernel context, might sleep.
1789  *
1790  *      RETURNS:
1791  *      Zero on success, AC_ERR_* mask on failure
1792  */
1793 unsigned ata_exec_internal_sg(struct ata_device *dev,
1794                               struct ata_taskfile *tf, const u8 *cdb,
1795                               int dma_dir, struct scatterlist *sgl,
1796                               unsigned int n_elem, unsigned long timeout)
1797 {
1798         struct ata_link *link = dev->link;
1799         struct ata_port *ap = link->ap;
1800         u8 command = tf->command;
1801         struct ata_queued_cmd *qc;
1802         unsigned int tag, preempted_tag;
1803         u32 preempted_sactive, preempted_qc_active;
1804         int preempted_nr_active_links;
1805         DECLARE_COMPLETION_ONSTACK(wait);
1806         unsigned long flags;
1807         unsigned int err_mask;
1808         int rc;
1809 
1810         spin_lock_irqsave(ap->lock, flags);
1811 
1812         /* no internal command while frozen */
1813         if (ap->pflags & ATA_PFLAG_FROZEN) {
1814                 spin_unlock_irqrestore(ap->lock, flags);
1815                 return AC_ERR_SYSTEM;
1816         }
1817 
1818         /* initialize internal qc */
1819 
1820         /* XXX: Tag 0 is used for drivers with legacy EH as some
1821          * drivers choke if any other tag is given.  This breaks
1822          * ata_tag_internal() test for those drivers.  Don't use new
1823          * EH stuff without converting to it.
1824          */
1825         if (ap->ops->error_handler)
1826                 tag = ATA_TAG_INTERNAL;
1827         else
1828                 tag = 0;
1829 
1830         if (test_and_set_bit(tag, &ap->qc_allocated))
1831                 BUG();
1832         qc = __ata_qc_from_tag(ap, tag);
1833 
1834         qc->tag = tag;
1835         qc->scsicmd = NULL;
1836         qc->ap = ap;
1837         qc->dev = dev;
1838         ata_qc_reinit(qc);
1839 
1840         preempted_tag = link->active_tag;
1841         preempted_sactive = link->sactive;
1842         preempted_qc_active = ap->qc_active;
1843         preempted_nr_active_links = ap->nr_active_links;
1844         link->active_tag = ATA_TAG_POISON;
1845         link->sactive = 0;
1846         ap->qc_active = 0;
1847         ap->nr_active_links = 0;
1848 
1849         /* prepare & issue qc */
1850         qc->tf = *tf;
1851         if (cdb)
1852                 memcpy(qc->cdb, cdb, ATAPI_CDB_LEN);
1853         qc->flags |= ATA_QCFLAG_RESULT_TF;
1854         qc->dma_dir = dma_dir;
1855         if (dma_dir != DMA_NONE) {
1856                 unsigned int i, buflen = 0;
1857                 struct scatterlist *sg;
1858 
1859                 for_each_sg(sgl, sg, n_elem, i)
1860                         buflen += sg->length;
1861 
1862                 ata_sg_init(qc, sgl, n_elem);
1863                 qc->nbytes = buflen;
1864         }
1865 
1866         qc->private_data = &wait;
1867         qc->complete_fn = ata_qc_complete_internal;
1868 
1869         ata_qc_issue(qc);
1870 
1871         spin_unlock_irqrestore(ap->lock, flags);
1872 
1873         if (!timeout)
1874                 timeout = ata_probe_timeout * 1000 / HZ;
1875 
1876         rc = wait_for_completion_timeout(&wait, msecs_to_jiffies(timeout));
1877 
1878         ata_port_flush_task(ap);
1879 
1880         if (!rc) {
1881                 spin_lock_irqsave(ap->lock, flags);
1882 
1883                 /* We're racing with irq here.  If we lose, the
1884                  * following test prevents us from completing the qc
1885                  * twice.  If we win, the port is frozen and will be
1886                  * cleaned up by ->post_internal_cmd().
1887                  */
1888                 if (qc->flags & ATA_QCFLAG_ACTIVE) {
1889                         qc->err_mask |= AC_ERR_TIMEOUT;
1890 
1891                         if (ap->ops->error_handler)
1892                                 ata_port_freeze(ap);
1893                         else
1894                                 ata_qc_complete(qc);
1895 
1896                         if (ata_msg_warn(ap))
1897                                 ata_dev_printk(dev, KERN_WARNING,
1898                                         "qc timeout (cmd 0x%x)\n", command);
1899                 }
1900 
1901                 spin_unlock_irqrestore(ap->lock, flags);
1902         }
1903 
1904         /* do post_internal_cmd */
1905         if (ap->ops->post_internal_cmd)
1906                 ap->ops->post_internal_cmd(qc);
1907 
1908         /* perform minimal error analysis */
1909         if (qc->flags & ATA_QCFLAG_FAILED) {
1910                 if (qc->result_tf.command & (ATA_ERR | ATA_DF))
1911                         qc->err_mask |= AC_ERR_DEV;
1912 
1913                 if (!qc->err_mask)
1914                         qc->err_mask |= AC_ERR_OTHER;
1915 
1916                 if (qc->err_mask & ~AC_ERR_OTHER)
1917                         qc->err_mask &= ~AC_ERR_OTHER;
1918         }
1919 
1920         /* finish up */
1921         spin_lock_irqsave(ap->lock, flags);
1922 
1923         *tf = qc->result_tf;
1924         err_mask = qc->err_mask;
1925 
1926         ata_qc_free(qc);
1927         link->active_tag = preempted_tag;
1928         link->sactive = preempted_sactive;
1929         ap->qc_active = preempted_qc_active;
1930         ap->nr_active_links = preempted_nr_active_links;
1931 
1932         /* XXX - Some LLDDs (sata_mv) disable port on command failure.
1933          * Until those drivers are fixed, we detect the condition
1934          * here, fail the command with AC_ERR_SYSTEM and reenable the
1935          * port.
1936          *
1937          * Note that this doesn't change any behavior as internal
1938          * command failure results in disabling the device in the
1939          * higher layer for LLDDs without new reset/EH callbacks.
1940          *
1941          * Kill the following code as soon as those drivers are fixed.
1942          */
1943         if (ap->flags & ATA_FLAG_DISABLED) {
1944                 err_mask |= AC_ERR_SYSTEM;
1945                 ata_port_probe(ap);
1946         }
1947 
1948         spin_unlock_irqrestore(ap->lock, flags);
1949 
1950         return err_mask;
1951 }
1952 
1953 /**
1954  *      ata_exec_internal - execute libata internal command
1955  *      @dev: Device to which the command is sent
1956  *      @tf: Taskfile registers for the command and the result
1957  *      @cdb: CDB for packet command
1958  *      @dma_dir: Data tranfer direction of the command
1959  *      @buf: Data buffer of the command
1960  *      @buflen: Length of data buffer
1961  *      @timeout: Timeout in msecs (0 for default)
1962  *
1963  *      Wrapper around ata_exec_internal_sg() which takes simple
1964  *      buffer instead of sg list.
1965  *
1966  *      LOCKING:
1967  *      None.  Should be called with kernel context, might sleep.
1968  *
1969  *      RETURNS:
1970  *      Zero on success, AC_ERR_* mask on failure
1971  */
1972 unsigned ata_exec_internal(struct ata_device *dev,
1973                            struct ata_taskfile *tf, const u8 *cdb,
1974                            int dma_dir, void *buf, unsigned int buflen,
1975                            unsigned long timeout)
1976 {
1977         struct scatterlist *psg = NULL, sg;
1978         unsigned int n_elem = 0;
1979 
1980         if (dma_dir != DMA_NONE) {
1981                 WARN_ON(!buf);
1982                 sg_init_one(&sg, buf, buflen);
1983                 psg = &sg;
1984                 n_elem++;
1985         }
1986 
1987         return ata_exec_internal_sg(dev, tf, cdb, dma_dir, psg, n_elem,
1988                                     timeout);
1989 }
1990 
1991 /**
1992  *      ata_do_simple_cmd - execute simple internal command
1993  *      @dev: Device to which the command is sent
1994  *      @cmd: Opcode to execute
1995  *
1996  *      Execute a 'simple' command, that only consists of the opcode
1997  *      'cmd' itself, without filling any other registers
1998  *
1999  *      LOCKING:
2000  *      Kernel thread context (may sleep).
2001  *
2002  *      RETURNS:
2003  *      Zero on success, AC_ERR_* mask on failure
2004  */
2005 unsigned int ata_do_simple_cmd(struct ata_device *dev, u8 cmd)
2006 {
2007         struct ata_taskfile tf;
2008 
2009         ata_tf_init(dev, &tf);
2010 
2011         tf.command = cmd;
2012         tf.flags |= ATA_TFLAG_DEVICE;
2013         tf.protocol = ATA_PROT_NODATA;
2014 
2015         return ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
2016 }
2017 
2018 /**
2019  *      ata_pio_need_iordy      -       check if iordy needed
2020  *      @adev: ATA device
2021  *
2022  *      Check if the current speed of the device requires IORDY. Used
2023  *      by various controllers for chip configuration.
2024  */
2025 
2026 unsigned int ata_pio_need_iordy(const struct ata_device *adev)
2027 {
2028         /* Controller doesn't support  IORDY. Probably a pointless check
2029            as the caller should know this */
2030         if (adev->link->ap->flags & ATA_FLAG_NO_IORDY)
2031                 return 0;
2032         /* PIO3 and higher it is mandatory */
2033         if (adev->pio_mode > XFER_PIO_2)
2034                 return 1;
2035         /* We turn it on when possible */
2036         if (ata_id_has_iordy(adev->id))
2037                 return 1;
2038         return 0;
2039 }
2040 
2041 /**
2042  *      ata_pio_mask_no_iordy   -       Return the non IORDY mask
2043  *      @adev: ATA device
2044  *
2045  *      Compute the highest mode possible if we are not using iordy. Return
2046  *      -1 if no iordy mode is available.
2047  */
2048 
2049 static u32 ata_pio_mask_no_iordy(const struct ata_device *adev)
2050 {
2051         /* If we have no drive specific rule, then PIO 2 is non IORDY */
2052         if (adev->id[ATA_ID_FIELD_VALID] & 2) { /* EIDE */
2053                 u16 pio = adev->id[ATA_ID_EIDE_PIO];
2054                 /* Is the speed faster than the drive allows non IORDY ? */
2055                 if (pio) {
2056                         /* This is cycle times not frequency - watch the logic! */
2057                         if (pio > 240)  /* PIO2 is 240nS per cycle */
2058                                 return 3 << ATA_SHIFT_PIO;
2059                         return 7 << ATA_SHIFT_PIO;
2060                 }
2061         }
2062         return 3 << ATA_SHIFT_PIO;
2063 }
2064 
2065 /**
2066  *      ata_dev_read_id - Read ID data from the specified device
2067  *      @dev: target device
2068  *      @p_class: pointer to class of the target device (may be changed)
2069  *      @flags: ATA_READID_* flags
2070  *      @id: buffer to read IDENTIFY data into
2071  *
2072  *      Read ID data from the specified device.  ATA_CMD_ID_ATA is
2073  *      performed on ATA devices and ATA_CMD_ID_ATAPI on ATAPI
2074  *      devices.  This function also issues ATA_CMD_INIT_DEV_PARAMS
2075  *      for pre-ATA4 drives.
2076  *
2077  *      FIXME: ATA_CMD_ID_ATA is optional for early drives and right
2078  *      now we abort if we hit that case.
2079  *
2080  *      LOCKING:
2081  *      Kernel thread context (may sleep)
2082  *
2083  *      RETURNS:
2084  *      0 on success, -errno otherwise.
2085  */
2086 int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class,
2087                     unsigned int flags, u16 *id)
2088 {
2089         struct ata_port *ap = dev->link->ap;
2090         unsigned int class = *p_class;
2091         struct ata_taskfile tf;
2092         unsigned int err_mask = 0;
2093         const char *reason;
2094         int may_fallback = 1, tried_spinup = 0;
2095         int rc;
2096 
2097         if (ata_msg_ctl(ap))
2098                 ata_dev_printk(dev, KERN_DEBUG, "%s: ENTER\n", __func__);
2099 
2100         ata_dev_select(ap, dev->devno, 1, 1); /* select device 0/1 */
2101  retry:
2102         ata_tf_init(dev, &tf);
2103 
2104         switch (class) {
2105         case ATA_DEV_ATA:
2106                 tf.command = ATA_CMD_ID_ATA;
2107                 break;
2108         case ATA_DEV_ATAPI:
2109                 tf.command = ATA_CMD_ID_ATAPI;
2110                 break;
2111         default:
2112                 rc = -ENODEV;
2113                 reason = "unsupported class";
2114                 goto err_out;
2115         }
2116 
2117         tf.protocol = ATA_PROT_PIO;
2118 
2119         /* Some devices choke if TF registers contain garbage.  Make
2120          * sure those are properly initialized.
2121          */
2122         tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2123 
2124         /* Device presence detection is unreliable on some
2125          * controllers.  Always poll IDENTIFY if available.
2126          */
2127         tf.flags |= ATA_TFLAG_POLLING;
2128 
2129         err_mask = ata_exec_internal(dev, &tf, NULL, DMA_FROM_DEVICE,
2130                                      id, sizeof(id[0]) * ATA_ID_WORDS, 0);
2131         if (err_mask) {
2132                 if (err_mask & AC_ERR_NODEV_HINT) {
2133                         ata_dev_printk(dev, KERN_DEBUG,
2134                                        "NODEV after polling detection\n");
2135                         return -ENOENT;
2136                 }
2137 
2138                 if ((err_mask == AC_ERR_DEV) && (tf.feature & ATA_ABORTED)) {
2139                         /* Device or controller might have reported
2140                          * the wrong device class.  Give a shot at the
2141                          * other IDENTIFY if the current one is
2142                          * aborted by the device.
2143                          */
2144                         if (may_fallback) {
2145                                 may_fallback = 0;
2146 
2147                                 if (class == ATA_DEV_ATA)
2148                                         class = ATA_DEV_ATAPI;
2149                                 else
2150                                         class = ATA_DEV_ATA;
2151                                 goto retry;
2152                         }
2153 
2154                         /* Control reaches here iff the device aborted
2155                          * both flavors of IDENTIFYs which happens
2156                          * sometimes with phantom devices.
2157                          */
2158                         ata_dev_printk(dev, KERN_DEBUG,
2159                                        "both IDENTIFYs aborted, assuming NODEV\n");
2160                         return -ENOENT;
2161                 }
2162 
2163                 rc = -EIO;
2164                 reason = "I/O error";
2165                 goto err_out;
2166         }
2167 
2168         /* Falling back doesn't make sense if ID data was read
2169          * successfully at least once.
2170          */
2171         may_fallback = 0;
2172 
2173         swap_buf_le16(id, ATA_ID_WORDS);
2174 
2175         /* sanity check */
2176         rc = -EINVAL;
2177         reason = "device reports invalid type";
2178 
2179         if (class == ATA_DEV_ATA) {
2180                 if (!ata_id_is_ata(id) && !ata_id_is_cfa(id))
2181                         goto err_out;
2182         } else {
2183                 if (ata_id_is_ata(id))
2184                         goto err_out;
2185         }
2186 
2187         if (!tried_spinup && (id[2] == 0x37c8 || id[2] == 0x738c)) {
2188                 tried_spinup = 1;
2189                 /*
2190                  * Drive powered-up in standby mode, and requires a specific
2191                  * SET_FEATURES spin-up subcommand before it will accept
2192                  * anything other than the original IDENTIFY command.
2193                  */
2194                 err_mask = ata_dev_set_feature(dev, SETFEATURES_SPINUP, 0);
2195                 if (err_mask && id[2] != 0x738c) {
2196                         rc = -EIO;
2197                         reason = "SPINUP failed";
2198                         goto err_out;
2199                 }
2200                 /*
2201                  * If the drive initially returned incomplete IDENTIFY info,
2202                  * we now must reissue the IDENTIFY command.
2203                  */
2204                 if (id[2] == 0x37c8)
2205                         goto retry;
2206         }
2207 
2208         if ((flags & ATA_READID_POSTRESET) && class == ATA_DEV_ATA) {
2209                 /*
2210                  * The exact sequence expected by certain pre-ATA4 drives is:
2211                  * SRST RESET
2212                  * IDENTIFY (optional in early ATA)
2213                  * INITIALIZE DEVICE PARAMETERS (later IDE and ATA)
2214                  * anything else..
2215                  * Some drives were very specific about that exact sequence.
2216                  *
2217                  * Note that ATA4 says lba is mandatory so the second check
2218                  * shoud never trigger.
2219                  */
2220                 if (ata_id_major_version(id) < 4 || !ata_id_has_lba(id)) {
2221                         err_mask = ata_dev_init_params(dev, id[3], id[6]);
2222                         if (err_mask) {
2223                                 rc = -EIO;
2224                                 reason = "INIT_DEV_PARAMS failed";
2225                                 goto err_out;
2226                         }
2227 
2228                         /* current CHS translation info (id[53-58]) might be
2229                          * changed. reread the identify device info.
2230                          */
2231                         flags &= ~ATA_READID_POSTRESET;
2232                         goto retry;
2233                 }
2234         }
2235 
2236         *p_class = class;
2237 
2238         return 0;
2239 
2240  err_out:
2241         if (ata_msg_warn(ap))
2242                 ata_dev_printk(dev, KERN_WARNING, "failed to IDENTIFY "
2243                                "(%s, err_mask=0x%x)\n", reason, err_mask);
2244         return rc;
2245 }
2246 
2247 static inline u8 ata_dev_knobble(struct ata_device *dev)
2248 {
2249         struct ata_port *ap = dev->link->ap;
2250         return ((ap->cbl == ATA_CBL_SATA) && (!ata_id_is_sata(dev->id)));
2251 }
2252 
2253 static void ata_dev_config_ncq(struct ata_device *dev,
2254                                char *desc, size_t desc_sz)
2255 {
2256         struct ata_port *ap = dev->link->ap;
2257         int hdepth = 0, ddepth = ata_id_queue_depth(dev->id);
2258 
2259         if (!ata_id_has_ncq(dev->id)) {
2260                 desc[0] = '\0';
2261                 return;
2262         }
2263         if (dev->horkage & ATA_HORKAGE_NONCQ) {
2264                 snprintf(desc, desc_sz, "NCQ (not used)");
2265                 return;
2266         }
2267         if (ap->flags & ATA_FLAG_NCQ) {
2268                 hdepth = min(ap->scsi_host->can_queue, ATA_MAX_QUEUE - 1);
2269                 dev->flags |= ATA_DFLAG_NCQ;
2270         }
2271 
2272         if (hdepth >= ddepth)
2273                 snprintf(desc, desc_sz, "NCQ (depth %d)", ddepth);
2274         else
2275                 snprintf(desc, desc_sz, "NCQ (depth %d/%d)", hdepth, ddepth);
2276 }
2277 
2278 /**
2279  *      ata_dev_configure - Configure the specified ATA/ATAPI device
2280  *      @dev: Target device to configure
2281  *
2282  *      Configure @dev according to @dev->id.  Generic and low-level
2283  *      driver specific fixups are also applied.
2284  *
2285  *      LOCKING:
2286  *      Kernel thread context (may sleep)
2287  *
2288  *      RETURNS:
2289  *      0 on success, -errno otherwise
2290  */
2291 int ata_dev_configure(struct ata_device *dev)
2292 {
2293         struct ata_port *ap = dev->link->ap;
2294         struct ata_eh_context *ehc = &dev->link->eh_context;
2295         int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
2296         const u16 *id = dev->id;
2297         unsigned long xfer_mask;
2298         char revbuf[7];         /* XYZ-99\0 */
2299         char fwrevbuf[ATA_ID_FW_REV_LEN+1];
2300         char modelbuf[ATA_ID_PROD_LEN+1];
2301         int rc;
2302 
2303         if (!ata_dev_enabled(dev) && ata_msg_info(ap)) {
2304                 ata_dev_printk(dev, KERN_INFO, "%s: ENTER/EXIT -- nodev\n",
2305                                __func__);
2306                 return 0;
2307         }
2308 
2309         if (ata_msg_probe(ap))
2310                 ata_dev_printk(dev, KERN_DEBUG, "%s: ENTER\n", __func__);
2311 
2312         /* set horkage */
2313         dev->horkage |= ata_dev_blacklisted(dev);
2314         ata_force_horkage(dev);
2315 
2316         /* let ACPI work its magic */
2317         rc = ata_acpi_on_devcfg(dev);
2318         if (rc)
2319                 return rc;
2320 
2321         /* massage HPA, do it early as it might change IDENTIFY data */
2322         rc = ata_hpa_resize(dev);
2323         if (rc)
2324                 return rc;
2325 
2326         /* print device capabilities */
2327         if (ata_msg_probe(ap))
2328                 ata_dev_printk(dev, KERN_DEBUG,
2329                                "%s: cfg 49:%04x 82:%04x 83:%04x 84:%04x "
2330                                "85:%04x 86:%04x 87:%04x 88:%04x\n",
2331                                __func__,
2332                                id[49], id[82], id[83], id[84],
2333                                id[85], id[86], id[87], id[88]);
2334 
2335         /* initialize to-be-configured parameters */
2336         dev->flags &= ~ATA_DFLAG_CFG_MASK;
2337         dev->max_sectors = 0;
2338         dev->cdb_len = 0;
2339         dev->n_sectors = 0;
2340         dev->cylinders = 0;
2341         dev->heads = 0;
2342         dev->sectors = 0;
2343 
2344         /*
2345          * common ATA, ATAPI feature tests
2346          */
2347 
2348         /* find max transfer mode; for printk only */
2349         xfer_mask = ata_id_xfermask(id);
2350 
2351         if (ata_msg_probe(ap))
2352                 ata_dump_id(id);
2353 
2354         /* SCSI only uses 4-char revisions, dump full 8 chars from ATA */
2355         ata_id_c_string(dev->id, fwrevbuf, ATA_ID_FW_REV,
2356                         sizeof(fwrevbuf));
2357 
2358         ata_id_c_string(dev->id, modelbuf, ATA_ID_PROD,
2359                         sizeof(modelbuf));
2360 
2361         /* ATA-specific feature tests */
2362         if (dev->class == ATA_DEV_ATA) {
2363                 if (ata_id_is_cfa(id)) {
2364                         if (id[162] & 1) /* CPRM may make this media unusable */
2365                                 ata_dev_printk(dev, KERN_WARNING,
2366                                                "supports DRM functions and may "
2367                                                "not be fully accessable.\n");
2368                         snprintf(revbuf, 7, "CFA");
2369                 } else {
2370                         snprintf(revbuf, 7, "ATA-%d", ata_id_major_version(id));
2371                         /* Warn the user if the device has TPM extensions */
2372                         if (ata_id_has_tpm(id))
2373                                 ata_dev_printk(dev, KERN_WARNING,
2374                                                "supports DRM functions and may "
2375                                                "not be fully accessable.\n");
2376                 }
2377 
2378                 dev->n_sectors = ata_id_n_sectors(id);
2379 
2380                 if (dev->id[59] & 0x100)
2381                         dev->multi_count = dev->id[59] & 0xff;
2382 
2383                 if (ata_id_has_lba(id)) {
2384                         const char *lba_desc;
2385                         char ncq_desc[20];
2386 
2387                         lba_desc = "LBA";
2388                         dev->flags |= ATA_DFLAG_LBA;
2389                         if (ata_id_has_lba48(id)) {
2390                                 dev->flags |= ATA_DFLAG_LBA48;
2391                                 lba_desc = "LBA48";
2392 
2393                                 if (dev->n_sectors >= (1UL << 28) &&
2394                                     ata_id_has_flush_ext(id))
2395                                         dev->flags |= ATA_DFLAG_FLUSH_EXT;
2396                         }
2397 
2398                         /* config NCQ */
2399                         ata_dev_config_ncq(dev, ncq_desc, sizeof(ncq_desc));
2400 
2401                         /* print device info to dmesg */
2402                         if (ata_msg_drv(ap) && print_info) {
2403                                 ata_dev_printk(dev, KERN_INFO,
2404                                         "%s: %s, %s, max %s\n",
2405                                         revbuf, modelbuf, fwrevbuf,
2406                                         ata_mode_string(xfer_mask));
2407                                 ata_dev_printk(dev, KERN_INFO,
2408                                         "%Lu sectors, multi %u: %s %s\n",
2409                                         (unsigned long long)dev->n_sectors,
2410                                         dev->multi_count, lba_desc, ncq_desc);
2411                         }
2412                 } else {
2413                         /* CHS */
2414 
2415                         /* Default translation */
2416                         dev->cylinders  = id[1];
2417                         dev->heads      = id[3];
2418                         dev->sectors    = id[6];
2419 
2420                         if (ata_id_current_chs_valid(id)) {
2421                                 /* Current CHS translation is valid. */
2422                                 dev->cylinders = id[54];
2423                                 dev->heads     = id[55];
2424                                 dev->sectors   = id[56];
2425                         }
2426 
2427                         /* print device info to dmesg */
2428                         if (ata_msg_drv(ap) && print_info) {
2429                                 ata_dev_printk(dev, KERN_INFO,
2430                                         "%s: %s, %s, max %s\n",
2431                                         revbuf, modelbuf, fwrevbuf,
2432                                         ata_mode_string(xfer_mask));
2433                                 ata_dev_printk(dev, KERN_INFO,
2434                                         "%Lu sectors, multi %u, CHS %u/%u/%u\n",
2435                                         (unsigned long long)dev->n_sectors,
2436                                         dev->multi_count, dev->cylinders,
2437                                         dev->heads, dev->sectors);
2438                         }
2439                 }
2440 
2441                 dev->cdb_len = 16;
2442         }
2443 
2444         /* ATAPI-specific feature tests */
2445         else if (dev->class == ATA_DEV_ATAPI) {
2446                 const char *cdb_intr_string = "";
2447                 const char *atapi_an_string = "";
2448                 const char *dma_dir_string = "";
2449                 u32 sntf;
2450 
2451                 rc = atapi_cdb_len(id);
2452                 if ((rc < 12) || (rc > ATAPI_CDB_LEN)) {
2453                         if (ata_msg_warn(ap))
2454                                 ata_dev_printk(dev, KERN_WARNING,
2455                                                "unsupported CDB len\n");
2456                         rc = -EINVAL;
2457                         goto err_out_nosup;
2458                 }
2459                 dev->cdb_len = (unsigned int) rc;
2460 
2461                 /* Enable ATAPI AN if both the host and device have
2462                  * the support.  If PMP is attached, SNTF is required
2463                  * to enable ATAPI AN to discern between PHY status
2464                  * changed notifications and ATAPI ANs.
2465                  */
2466                 if ((ap->flags & ATA_FLAG_AN) && ata_id_has_atapi_AN(id) &&
2467                     (!ap->nr_pmp_links ||
2468                      sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf) == 0)) {
2469                         unsigned int err_mask;
2470 
2471                         /* issue SET feature command to turn this on */
2472                         err_mask = ata_dev_set_feature(dev,
2473                                         SETFEATURES_SATA_ENABLE, SATA_AN);
2474                         if (err_mask)
2475                                 ata_dev_printk(dev, KERN_ERR,
2476                                         "failed to enable ATAPI AN "
2477                                         "(err_mask=0x%x)\n", err_mask);
2478                         else {
2479                                 dev->flags |= ATA_DFLAG_AN;
2480                                 atapi_an_string = ", ATAPI AN";
2481                         }
2482                 }
2483 
2484                 if (ata_id_cdb_intr(dev->id)) {
2485                         dev->flags |= ATA_DFLAG_CDB_INTR;
2486                         cdb_intr_string = ", CDB intr";
2487                 }
2488 
2489                 if (atapi_dmadir || atapi_id_dmadir(dev->id)) {
2490                         dev->flags |= ATA_DFLAG_DMADIR;
2491                         dma_dir_string = ", DMADIR";
2492                 }
2493 
2494                 /* print device info to dmesg */
2495                 if (ata_msg_drv(ap) && print_info)
2496                         ata_dev_printk(dev, KERN_INFO,
2497                                        "ATAPI: %s, %s, max %s%s%s%s\n",
2498                                        modelbuf, fwrevbuf,
2499                                        ata_mode_string(xfer_mask),
2500                                        cdb_intr_string, atapi_an_string,
2501                                        dma_dir_string);
2502         }
2503 
2504         /* determine max_sectors */
2505         dev->max_sectors = ATA_MAX_SECTORS;
2506         if (dev->flags & ATA_DFLAG_LBA48)
2507                 dev->max_sectors = ATA_MAX_SECTORS_LBA48;
2508 
2509         if (!(dev->horkage & ATA_HORKAGE_IPM)) {
2510                 if (ata_id_has_hipm(dev->id))
2511                         dev->flags |= ATA_DFLAG_HIPM;
2512                 if (ata_id_has_dipm(dev->id))
2513                         dev->flags |= ATA_DFLAG_DIPM;
2514         }
2515 
2516         /* Limit PATA drive on SATA cable bridge transfers to udma5,
2517            200 sectors */
2518         if (ata_dev_knobble(dev)) {
2519                 if (ata_msg_drv(ap) && print_info)
2520                         ata_dev_printk(dev, KERN_INFO,
2521                                        "applying bridge limits\n");
2522                 dev->udma_mask &= ATA_UDMA5;
2523                 dev->max_sectors = ATA_MAX_SECTORS;
2524         }
2525 
2526         if ((dev->class == ATA_DEV_ATAPI) &&
2527             (atapi_command_packet_set(id) == TYPE_TAPE)) {
2528                 dev->max_sectors = ATA_MAX_SECTORS_TAPE;
2529                 dev->horkage |= ATA_HORKAGE_STUCK_ERR;
2530         }
2531 
2532         if (dev->horkage & ATA_HORKAGE_MAX_SEC_128)
2533                 dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_128,
2534                                          dev->max_sectors);
2535 
2536         if (ata_dev_blacklisted(dev) & ATA_HORKAGE_IPM) {
2537                 dev->horkage |= ATA_HORKAGE_IPM;
2538 
2539                 /* reset link pm_policy for this port to no pm */
2540                 ap->pm_policy = MAX_PERFORMANCE;
2541         }
2542 
2543         if (ap->ops->dev_config)
2544                 ap->ops->dev_config(dev);
2545 
2546         if (dev->horkage & ATA_HORKAGE_DIAGNOSTIC) {
2547                 /* Let the user know. We don't want to disallow opens for
2548                    rescue purposes, or in case the vendor is just a blithering
2549                    idiot. Do this after the dev_config call as some controllers
2550                    with buggy firmware may want to avoid reporting false device
2551                    bugs */
2552 
2553                 if (print_info) {
2554                         ata_dev_printk(dev, KERN_WARNING,
2555 "Drive reports diagnostics failure. This may indicate a drive\n");
2556                         ata_dev_printk(dev, KERN_WARNING,
2557 "fault or invalid emulation. Contact drive vendor for information.\n");
2558                 }
2559         }
2560 
2561         if (ata_msg_probe(ap))
2562                 ata_dev_printk(dev, KERN_DEBUG, "%s: EXIT, drv_stat = 0x%x\n",
2563                         __func__, ata_chk_status(ap));
2564         return 0;
2565 
2566 err_out_nosup:
2567         if (ata_msg_probe(ap))
2568                 ata_dev_printk(dev, KERN_DEBUG,
2569                                "%s: EXIT, err\n", __func__);
2570         return rc;
2571 }
2572 
2573 /**
2574  *      ata_cable_40wire        -       return 40 wire cable type
2575  *      @ap: port
2576  *
2577  *      Helper method for drivers which want to hardwire 40 wire cable
2578  *      detection.
2579  */
2580 
2581 int ata_cable_40wire(struct ata_port *ap)
2582 {
2583         return ATA_CBL_PATA40;
2584 }
2585 
2586 /**
2587  *      ata_cable_80wire        -       return 80 wire cable type
2588  *      @ap: port
2589  *
2590  *      Helper method for drivers which want to hardwire 80 wire cable
2591  *      detection.
2592  */
2593 
2594 int ata_cable_80wire(struct ata_port *ap)
2595 {
2596         return ATA_CBL_PATA80;
2597 }
2598 
2599 /**
2600  *      ata_cable_unknown       -       return unknown PATA cable.
2601  *      @ap: port
2602  *
2603  *      Helper method for drivers which have no PATA cable detection.
2604  */
2605 
2606 int ata_cable_unknown(struct ata_port *ap)
2607 {
2608         return ATA_CBL_PATA_UNK;
2609 }
2610 
2611 /**
2612  *      ata_cable_ignore        -       return ignored PATA cable.
2613  *      @ap: port
2614  *
2615  *      Helper method for drivers which don't use cable type to limit
2616  *      transfer mode.
2617  */
2618 int ata_cable_ignore(struct ata_port *ap)
2619 {
2620         return ATA_CBL_PATA_IGN;
2621 }
2622 
2623 /**
2624  *      ata_cable_sata  -       return SATA cable type
2625  *      @ap: port
2626  *
2627  *      Helper method for drivers which have SATA cables
2628  */
2629 
2630 int ata_cable_sata(struct ata_port *ap)
2631 {
2632         return ATA_CBL_SATA;
2633 }
2634 
2635 /**
2636  *      ata_bus_probe - Reset and probe ATA bus
2637  *      @ap: Bus to probe
2638  *
2639  *      Master ATA bus probing function.  Initiates a hardware-dependent
2640  *      bus reset, then attempts to identify any devices found on
2641  *      the bus.
2642  *
2643  *      LOCKING:
2644  *      PCI/etc. bus probe sem.
2645  *
2646  *      RETURNS:
2647  *      Zero on success, negative errno otherwise.
2648  */
2649 
2650 int ata_bus_probe(struct ata_port *ap)
2651 {
2652         unsigned int classes[ATA_MAX_DEVICES];
2653         int tries[ATA_MAX_DEVICES];
2654         int rc;
2655         struct ata_device *dev;
2656 
2657         ata_port_probe(ap);
2658 
2659         ata_link_for_each_dev(dev, &ap->link)
2660                 tries[dev->devno] = ATA_PROBE_MAX_TRIES;
2661 
2662  retry:
2663         ata_link_for_each_dev(dev, &ap->link) {
2664                 /* If we issue an SRST then an ATA drive (not ATAPI)
2665                  * may change configuration and be in PIO0 timing. If
2666                  * we do a hard reset (or are coming from power on)
2667                  * this is true for ATA or ATAPI. Until we've set a
2668                  * suitable controller mode we should not touch the
2669                  * bus as we may be talking too fast.
2670                  */
2671                 dev->pio_mode = XFER_PIO_0;
2672 
2673                 /* If the controller has a pio mode setup function
2674                  * then use it to set the chipset to rights. Don't
2675                  * touch the DMA setup as that will be dealt with when
2676                  * configuring devices.
2677                  */
2678                 if (ap->ops->set_piomode)
2679                         ap->ops->set_piomode(ap, dev);
2680         }
2681 
2682         /* reset and determine device classes */
2683         ap->ops->phy_reset(ap);
2684 
2685         ata_link_for_each_dev(dev, &ap->link) {
2686                 if (!(ap->flags & ATA_FLAG_DISABLED) &&
2687                     dev->class != ATA_DEV_UNKNOWN)
2688                         classes[dev->devno] = dev->class;
2689                 else
2690                         classes[dev->devno] = ATA_DEV_NONE;
2691 
2692                 dev->class = ATA_DEV_UNKNOWN;
2693         }
2694 
2695         ata_port_probe(ap);
2696 
2697         /* read IDENTIFY page and configure devices. We have to do the identify
2698            specific sequence bass-ackwards so that PDIAG- is released by
2699            the slave device */
2700 
2701         ata_link_for_each_dev_reverse(dev, &ap->link) {
2702                 if (tries[dev->devno])
2703                         dev->class = classes[dev->devno];
2704 
2705                 if (!ata_dev_enabled(dev))
2706                         continue;
2707 
2708                 rc = ata_dev_read_id(dev, &dev->class, ATA_READID_POSTRESET,
2709                                      dev->id);
2710                 if (rc)
2711                         goto fail;
2712         }
2713 
2714         /* Now ask for the cable type as PDIAG- should have been released */
2715         if (ap->ops->cable_detect)
2716                 ap->cbl = ap->ops->cable_detect(ap);
2717 
2718         /* We may have SATA bridge glue hiding here irrespective of the
2719            reported cable types and sensed types */
2720         ata_link_for_each_dev(dev, &ap->link) {
2721                 if (!ata_dev_enabled(dev))
2722                         continue;
2723                 /* SATA drives indicate we have a bridge. We don't know which
2724                    end of the link the bridge is which is a problem */
2725                 if (ata_id_is_sata(dev->id))
2726                         ap->cbl = ATA_CBL_SATA;
2727         }
2728 
2729         /* After the identify sequence we can now set up the devices. We do
2730            this in the normal order so that the user doesn't get confused */
2731 
2732         ata_link_for_each_dev(dev, &ap->link) {
2733                 if (!ata_dev_enabled(dev))
2734                         continue;
2735 
2736                 ap->link.eh_context.i.flags |= ATA_EHI_PRINTINFO;
2737                 rc = ata_dev_configure(dev);
2738                 ap->link.eh_context.i.flags &= ~ATA_EHI_PRINTINFO;
2739                 if (rc)
2740                         goto fail;
2741         }
2742 
2743         /* configure transfer mode */
2744         rc = ata_set_mode(&ap->link, &dev);
2745         if (rc)
2746                 goto fail;
2747 
2748         ata_link_for_each_dev(dev, &ap->link)
2749                 if (ata_dev_enabled(dev))
2750                         return 0;
2751 
2752         /* no device present, disable port */
2753         ata_port_disable(ap);
2754         return -ENODEV;
2755 
2756  fail:
2757         tries[dev->devno]--;
2758 
2759         switch (rc) {
2760         case -EINVAL:
2761                 /* eeek, something went very wrong, give up */
2762                 tries[dev->devno] = 0;
2763                 break;
2764 
2765         case -ENODEV:
2766                 /* give it just one more chance */
2767                 tries[dev->devno] = min(tries[dev->devno], 1);
2768         case -EIO:
2769                 if (tries[dev->devno] == 1) {
2770                         /* This is the last chance, better to slow
2771                          * down than lose it.
2772                          */
2773                         sata_down_spd_limit(&ap->link);
2774                         ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
2775                 }
2776         }
2777 
2778         if (!tries[dev->devno])
2779                 ata_dev_disable(dev);
2780 
2781         goto retry;
2782 }
2783 
2784 /**
2785  *      ata_port_probe - Mark port as enabled
2786  *      @ap: Port for which we indicate enablement
2787  *
2788  *      Modify @ap data structure such that the system
2789  *      thinks that the entire port is enabled.
2790  *
2791  *      LOCKING: host lock, or some other form of
2792  *      serialization.
2793  */
2794 
2795 void ata_port_probe(struct ata_port *ap)
2796 {
2797         ap->flags &= ~ATA_FLAG_DISABLED;
2798 }
2799 
2800 /**
2801  *      sata_print_link_status - Print SATA link status
2802  *      @link: SATA link to printk link status about
2803  *
2804  *      This function prints link speed and status of a SATA link.
2805  *
2806  *      LOCKING:
2807  *      None.
2808  */
2809 void sata_print_link_status(struct ata_link *link)
2810 {
2811         u32 sstatus, scontrol, tmp;
2812 
2813         if (sata_scr_read(link, SCR_STATUS, &sstatus))
2814                 return;
2815         sata_scr_read(link, SCR_CONTROL, &scontrol);
2816 
2817         if (ata_link_online(link)) {
2818                 tmp = (sstatus >> 4) & 0xf;
2819                 ata_link_printk(link, KERN_INFO,
2820                                 "SATA link up %s (SStatus %X SControl %X)\n",
2821                                 sata_spd_string(tmp), sstatus, scontrol);
2822         } else {
2823                 ata_link_printk(link, KERN_INFO,
2824                                 "SATA link down (SStatus %X SControl %X)\n",
2825                                 sstatus, scontrol);
2826         }
2827 }
2828 
2829 /**
2830  *      ata_dev_pair            -       return other device on cable
2831  *      @adev: device
2832  *
2833  *      Obtain the other device on the same cable, or if none is
2834  *      present NULL is returned
2835  */
2836 
2837 struct ata_device *ata_dev_pair(struct ata_device *adev)
2838 {
2839         struct ata_link *link = adev->link;
2840         struct ata_device *pair = &link->device[1 - adev->devno];
2841         if (!ata_dev_enabled(pair))
2842                 return NULL;
2843         return pair;
2844 }
2845 
2846 /**
2847  *      ata_port_disable - Disable port.
2848  *      @ap: Port to be disabled.
2849  *
2850  *      Modify @ap data structure such that the system
2851  *      thinks that the entire port is disabled, and should
2852  *      never attempt to probe or communicate with devices
2853  *      on this port.
2854  *
2855  *      LOCKING: host lock, or some other form of
2856  *      serialization.
2857  */
2858 
2859 void ata_port_disable(struct ata_port *ap)
2860 {
2861         ap->link.device[0].class = ATA_DEV_NONE;
2862         ap->link.device[1].class = ATA_DEV_NONE;
2863         ap->flags |= ATA_FLAG_DISABLED;
2864 }
2865 
2866 /**
2867  *      sata_down_spd_limit - adjust SATA spd limit downward
2868  *      @link: Link to adjust SATA spd limit for
2869  *
2870  *      Adjust SATA spd limit of @link downward.  Note that this
2871  *      function only adjusts the limit.  The change must be applied
2872  *      using sata_set_spd().
2873  *
2874  *      LOCKING:
2875  *      Inherited from caller.
2876  *
2877  *      RETURNS:
2878  *      0 on success, negative errno on failure
2879  */
2880 int sata_down_spd_limit(struct ata_link *link)
2881 {
2882         u32 sstatus, spd, mask;
2883         int rc, highbit;
2884 
2885         if (!sata_scr_valid(link))
2886                 return -EOPNOTSUPP;
2887 
2888         /* If SCR can be read, use it to determine the current SPD.
2889          * If not, use cached value in link->sata_spd.
2890          */
2891         rc = sata_scr_read(link, SCR_STATUS, &sstatus);
2892         if (rc == 0)
2893                 spd = (sstatus >> 4) & 0xf;
2894         else
2895                 spd = link->sata_spd;
2896 
2897         mask = link->sata_spd_limit;
2898         if (mask <= 1)
2899                 return -EINVAL;
2900 
2901         /* unconditionally mask off the highest bit */
2902         highbit = fls(mask) - 1;
2903         mask &= ~(1 << highbit);
2904 
2905         /* Mask off all speeds higher than or equal to the current
2906          * one.  Force 1.5Gbps if current SPD is not available.
2907          */
2908         if (spd > 1)
2909                 mask &= (1 << (spd - 1)) - 1;
2910         else
2911                 mask &= 1;
2912 
2913         /* were we already at the bottom? */
2914         if (!mask)
2915                 return -EINVAL;
2916 
2917         link->sata_spd_limit = mask;
2918 
2919         ata_link_printk(link, KERN_WARNING, "limiting SATA link speed to %s\n",
2920                         sata_spd_string(fls(mask)));
2921 
2922         return 0;
2923 }
2924 
2925 static int __sata_set_spd_needed(struct ata_link *link, u32 *scontrol)
2926 {
2927         struct ata_link *host_link = &link->ap->link;
2928         u32 limit, target, spd;
2929 
2930         limit = link->sata_spd_limit;
2931 
2932         /* Don't configure downstream link faster than upstream link.
2933          * It doesn't speed up anything and some PMPs choke on such
2934          * configuration.
2935          */
2936         if (!ata_is_host_link(link) && host_link->sata_spd)
2937                 limit &= (1 << host_link->sata_spd) - 1;
2938 
2939         if (limit == UINT_MAX)
2940                 target = 0;
2941         else
2942                 target = fls(limit);
2943 
2944         spd = (*scontrol >> 4) & 0xf;
2945         *scontrol = (*scontrol & ~0xf0) | ((target & 0xf) << 4);
2946 
2947         return spd != target;
2948 }
2949 
2950 /**
2951  *      sata_set_spd_needed - is SATA spd configuration needed
2952  *      @link: Link in question
2953  *
2954  *      Test whether the spd limit in SControl matches
2955  *      @link->sata_spd_limit.  This function is used to determine
2956  *      whether hardreset is necessary to apply SATA spd
2957  *      configuration.
2958  *
2959  *      LOCKING:
2960  *      Inherited from caller.
2961  *
2962  *      RETURNS:
2963  *      1 if SATA spd configuration is needed, 0 otherwise.
2964  */
2965 int sata_set_spd_needed(struct ata_link *link)
2966 {
2967         u32 scontrol;
2968 
2969         if (sata_scr_read(link, SCR_CONTROL, &scontrol))
2970                 return 1;
2971 
2972         return __sata_set_spd_needed(link, &scontrol);
2973 }
2974 
2975 /**
2976  *      sata_set_spd - set SATA spd according to spd limit
2977  *      @link: Link to set SATA spd for
2978  *
2979  *      Set SATA spd of @link according to sata_spd_limit.
2980  *
2981  *      LOCKING:
2982  *      Inherited from caller.
2983  *
2984  *      RETURNS:
2985  *      0 if spd doesn't need to be changed, 1 if spd has been
2986  *      changed.  Negative errno if SCR registers are inaccessible.
2987  */
2988 int sata_set_spd(struct ata_link *link)
2989 {
2990         u32 scontrol;
2991         int rc;
2992 
2993         if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
2994                 return rc;
2995 
2996         if (!__sata_set_spd_needed(link, &scontrol))
2997                 return 0;
2998 
2999         if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3000                 return rc;
3001 
3002         return 1;
3003 }
3004 
3005 /*
3006  * This mode timing computation functionality is ported over from
3007  * drivers/ide/ide-timing.h and was originally written by Vojtech Pavlik
3008  */
3009 /*
3010  * PIO 0-4, MWDMA 0-2 and UDMA 0-6 timings (in nanoseconds).
3011  * These were taken from ATA/ATAPI-6 standard, rev 0a, except
3012  * for UDMA6, which is currently supported only by Maxtor drives.
3013  *
3014  * For PIO 5/6 MWDMA 3/4 see the CFA specification 3.0.
3015  */
3016 
3017 static const struct ata_timing ata_timing[] = {
3018 /*      { XFER_PIO_SLOW, 120, 290, 240, 960, 290, 240, 960,   0 }, */
3019         { XFER_PIO_0,     70, 290, 240, 600, 165, 150, 600,   0 },
3020         { XFER_PIO_1,     50, 290,  93, 383, 125, 100, 383,   0 },
3021         { XFER_PIO_2,     30, 290,  40, 330, 100,  90, 240,   0 },
3022         { XFER_PIO_3,     30,  80,  70, 180,  80,  70, 180,   0 },
3023         { XFER_PIO_4,     25,  70,  25, 120,  70,  25, 120,   0 },
3024         { XFER_PIO_5,     15,  65,  25, 100,  65,  25, 100,   0 },
3025         { XFER_PIO_6,     10,  55,  20,  80,  55,  20,  80,   0 },
3026 
3027         { XFER_SW_DMA_0, 120,   0,   0,   0, 480, 480, 960,   0 },
3028         { XFER_SW_DMA_1,  90,   0,   0,   0, 240, 240, 480,   0 },
3029         { XFER_SW_DMA_2,  60,   0,   0,   0, 120, 120, 240,   0 },
3030 
3031         { XFER_MW_DMA_0,  60,   0,   0,   0, 215, 215, 480,   0 },
3032         { XFER_MW_DMA_1,  45,   0,   0,   0,  80,  50, 150,   0 },
3033         { XFER_MW_DMA_2,  25,   0,   0,   0,  70,  25, 120,   0 },
3034         { XFER_MW_DMA_3,  25,   0,   0,   0,  65,  25, 100,   0 },
3035         { XFER_MW_DMA_4,  25,   0,   0,   0,  55,  20,  80,   0 },
3036 
3037 /*      { XFER_UDMA_SLOW,  0,   0,   0,   0,   0,   0,   0, 150 }, */
3038         { XFER_UDMA_0,     0,   0,   0,   0,   0,   0,   0, 120 },
3039         { XFER_UDMA_1,     0,   0,   0,   0,   0,   0,   0,  80 },
3040         { XFER_UDMA_2,     0,   0,   0,   0,   0,   0,   0,  60 },
3041         { XFER_UDMA_3,     0,   0,   0,   0,   0,   0,   0,  45 },
3042         { XFER_UDMA_4,     0,   0,   0,   0,   0,   0,   0,  30 },
3043         { XFER_UDMA_5,     0,   0,   0,   0,   0,   0,   0,  20 },
3044         { XFER_UDMA_6,     0,   0,   0,   0,   0,   0,   0,  15 },
3045 
3046         { 0xFF }
3047 };
3048 
3049 #define ENOUGH(v, unit)         (((v)-1)/(unit)+1)
3050 #define EZ(v, unit)             ((v)?ENOUGH(v, unit):0)
3051 
3052 static void ata_timing_quantize(const struct ata_timing *t, struct ata_timing *q, int T, int UT)
3053 {
3054         q->setup   = EZ(t->setup   * 1000,  T);
3055         q->act8b   = EZ(t->act8b   * 1000,  T);
3056         q->rec8b   = EZ(t->rec8b   * 1000,  T);
3057         q->cyc8b   = EZ(t->cyc8b   * 1000,  T);
3058         q->active  = EZ(t->active  * 1000,  T);
3059         q->recover = EZ(t->recover * 1000,  T);
3060         q->cycle   = EZ(t->cycle   * 1000,  T);
3061         q->udma    = EZ(t->udma    * 1000, UT);
3062 }
3063 
3064 void ata_timing_merge(const struct ata_timing *a, const struct ata_timing *b,
3065                       struct ata_timing *m, unsigned int what)
3066 {
3067         if (what & ATA_TIMING_SETUP  ) m->setup   = max(a->setup,   b->setup);
3068         if (what & ATA_TIMING_ACT8B  ) m->act8b   = max(a->act8b,   b->act8b);
3069         if (what & ATA_TIMING_REC8B  ) m->rec8b   = max(a->rec8b,   b->rec8b);
3070         if (what & ATA_TIMING_CYC8B  ) m->cyc8b   = max(a->cyc8b,   b->cyc8b);
3071         if (what & ATA_TIMING_ACTIVE ) m->active  = max(a->active,  b->active);
3072         if (what & ATA_TIMING_RECOVER) m->recover = max(a->recover, b->recover);
3073         if (what & ATA_TIMING_CYCLE  ) m->cycle   = max(a->cycle,   b->cycle);
3074         if (what & ATA_TIMING_UDMA   ) m->udma    = max(a->udma,    b->udma);
3075 }
3076 
3077 const struct ata_timing *ata_timing_find_mode(u8 xfer_mode)
3078 {
3079         const struct ata_timing *t = ata_timing;
3080 
3081         while (xfer_mode > t->mode)
3082                 t++;
3083 
3084         if (xfer_mode == t->mode)
3085                 return t;
3086         return NULL;
3087 }
3088 
3089 int ata_timing_compute(struct ata_device *adev, unsigned short speed,
3090                        struct ata_timing *t, int T, int UT)
3091 {
3092         const struct ata_timing *s;
3093         struct ata_timing p;
3094 
3095         /*
3096          * Find the mode.
3097          */
3098 
3099         if (!(s = ata_timing_find_mode(speed)))
3100                 return -EINVAL;
3101 
3102         memcpy(t, s, sizeof(*s));
3103 
3104         /*
3105          * If the drive is an EIDE drive, it can tell us it needs extended
3106          * PIO/MW_DMA cycle timing.
3107          */
3108 
3109         if (adev->id[ATA_ID_FIELD_VALID] & 2) { /* EIDE drive */
3110                 memset(&p, 0, sizeof(p));
3111                 if (speed >= XFER_PIO_0 && speed <= XFER_SW_DMA_0) {
3112                         if (speed <= XFER_PIO_2) p.cycle = p.cyc8b = adev->id[ATA_ID_EIDE_PIO];
3113                                             else p.cycle = p.cyc8b = adev->id[ATA_ID_EIDE_PIO_IORDY];
3114                 } else if (speed >= XFER_MW_DMA_0 && speed <= XFER_MW_DMA_2) {
3115                         p.cycle = adev->id[ATA_ID_EIDE_DMA_MIN];
3116                 }
3117                 ata_timing_merge(&p, t, t, ATA_TIMING_CYCLE | ATA_TIMING_CYC8B);
3118         }
3119 
3120         /*
3121          * Convert the timing to bus clock counts.
3122          */
3123 
3124         ata_timing_quantize(t, t, T, UT);
3125 
3126         /*
3127          * Even in DMA/UDMA modes we still use PIO access for IDENTIFY,
3128          * S.M.A.R.T * and some other commands. We have to ensure that the
3129          * DMA cycle timing is slower/equal than the fastest PIO timing.
3130          */
3131 
3132         if (speed > XFER_PIO_6) {
3133                 ata_timing_compute(adev, adev->pio_mode, &p, T, UT);
3134                 ata_timing_merge(&p, t, t, ATA_TIMING_ALL);
3135         }
3136 
3137         /*
3138          * Lengthen active & recovery time so that cycle time is correct.
3139          */
3140 
3141         if (t->act8b + t->rec8b < t->cyc8b) {
3142                 t->act8b += (t->cyc8b - (t->act8b + t->rec8b)) / 2;
3143                 t->rec8b = t->cyc8b - t->act8b;
3144         }
3145 
3146         if (t->active + t->recover < t->cycle) {
3147                 t->active += (t->cycle - (t->active + t->recover)) / 2;
3148                 t->recover = t->cycle - t->active;
3149         }
3150 
3151         /* In a few cases quantisation may produce enough errors to
3152            leave t->cycle too low for the sum of active and recovery
3153            if so we must correct this */
3154         if (t->active + t->recover > t->cycle)
3155                 t->cycle = t->active + t->recover;
3156 
3157         return 0;
3158 }
3159 
3160 /**
3161  *      ata_timing_cycle2mode - find xfer mode for the specified cycle duration
3162  *      @xfer_shift: ATA_SHIFT_* value for transfer type to examine.
3163  *      @cycle: cycle duration in ns
3164  *
3165  *      Return matching xfer mode for @cycle.  The returned mode is of
3166  *      the transfer type specified by @xfer_shift.  If @cycle is too
3167  *      slow for @xfer_shift, 0xff is returned.  If @cycle is faster
3168  *      than the fastest known mode, the fasted mode is returned.
3169  *
3170  *      LOCKING:
3171  *      None.
3172  *
3173  *      RETURNS:
3174  *      Matching xfer_mode, 0xff if no match found.
3175  */
3176 u8 ata_timing_cycle2mode(unsigned int xfer_shift, int cycle)
3177 {
3178         u8 base_mode = 0xff, last_mode = 0xff;
3179         const struct ata_xfer_ent *ent;
3180         const struct ata_timing *t;
3181 
3182         for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
3183                 if (ent->shift == xfer_shift)
3184                         base_mode = ent->base;
3185 
3186         for (t = ata_timing_find_mode(base_mode);
3187              t && ata_xfer_mode2shift(t->mode) == xfer_shift; t++) {
3188                 unsigned short this_cycle;
3189 
3190                 switch (xfer_shift) {
3191                 case ATA_SHIFT_PIO:
3192                 case ATA_SHIFT_MWDMA:
3193                         this_cycle = t->cycle;
3194                         break;
3195                 case ATA_SHIFT_UDMA:
3196                         this_cycle = t->udma;
3197                         break;
3198                 default:
3199                         return 0xff;
3200                 }
3201 
3202                 if (cycle > this_cycle)
3203                         break;
3204 
3205                 last_mode = t->mode;
3206         }
3207 
3208         return last_mode;
3209 }
3210 
3211 /**
3212  *      ata_down_xfermask_limit - adjust dev xfer masks downward
3213  *      @dev: Device to adjust xfer masks
3214  *      @sel: ATA_DNXFER_* selector
3215  *
3216  *      Adjust xfer masks of @dev downward.  Note that this function
3217  *      does not apply the change.  Invoking ata_set_mode() afterwards
3218  *      will apply the limit.
3219  *
3220  *      LOCKING:
3221  *      Inherited from caller.
3222  *
3223  *      RETURNS:
3224  *      0 on success, negative errno on failure
3225  */
3226 int ata_down_xfermask_limit(struct ata_device *dev, unsigned int sel)
3227 {
3228         char buf[32];
3229         unsigned long orig_mask, xfer_mask;
3230         unsigned long pio_mask, mwdma_mask, udma_mask;
3231         int quiet, highbit;
3232 
3233         quiet = !!(sel & ATA_DNXFER_QUIET);
3234         sel &= ~ATA_DNXFER_QUIET;
3235 
3236         xfer_mask = orig_mask = ata_pack_xfermask(dev->pio_mask,
3237                                                   dev->mwdma_mask,
3238                                                   dev->udma_mask);
3239         ata_unpack_xfermask(xfer_mask, &pio_mask, &mwdma_mask, &udma_mask);
3240 
3241         switch (sel) {
3242         case ATA_DNXFER_PIO:
3243                 highbit = fls(pio_mask) - 1;
3244                 pio_mask &= ~(1 << highbit);
3245                 break;
3246 
3247         case ATA_DNXFER_DMA:
3248                 if (udma_mask) {
3249                         highbit = fls(udma_mask) - 1;
3250                         udma_mask &= ~(1 << highbit);
3251                         if (!udma_mask)
3252                                 return -ENOENT;
3253                 } else if (mwdma_mask) {
3254                         highbit = fls(mwdma_mask) - 1;
3255                         mwdma_mask &= ~(1 << highbit);
3256                         if (!mwdma_mask)
3257                                 return -ENOENT;
3258                 }
3259                 break;
3260 
3261         case ATA_DNXFER_40C:
3262                 udma_mask &= ATA_UDMA_MASK_40C;
3263                 break;
3264 
3265         case ATA_DNXFER_FORCE_PIO0:
3266                 pio_mask &= 1;
3267         case ATA_DNXFER_FORCE_PIO:
3268                 mwdma_mask = 0;
3269                 udma_mask = 0;
3270                 break;
3271 
3272         default:
3273                 BUG();
3274         }
3275 
3276         xfer_mask &= ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
3277 
3278         if (!(xfer_mask & ATA_MASK_PIO) || xfer_mask == orig_mask)
3279                 return -ENOENT;
3280 
3281         if (!quiet) {
3282                 if (xfer_mask & (ATA_MASK_MWDMA | ATA_MASK_UDMA))
3283                         snprintf(buf, sizeof(buf), "%s:%s",
3284                                  ata_mode_string(xfer_mask),
3285                                  ata_mode_string(xfer_mask & ATA_MASK_PIO));
3286                 else
3287                         snprintf(buf, sizeof(buf), "%s",
3288                                  ata_mode_string(xfer_mask));
3289 
3290                 ata_dev_printk(dev, KERN_WARNING,
3291                                "limiting speed to %s\n", buf);
3292         }
3293 
3294         ata_unpack_xfermask(xfer_mask, &dev->pio_mask, &dev->mwdma_mask,
3295                             &dev->udma_mask);
3296 
3297         return 0;
3298 }
3299 
3300 static int ata_dev_set_mode(struct ata_device *dev)
3301 {
3302         struct ata_eh_context *ehc = &dev->link->eh_context;
3303         const char *dev_err_whine = "";
3304         int ign_dev_err = 0;
3305         unsigned int err_mask;
3306         int rc;
3307 
3308         dev->flags &= ~ATA_DFLAG_PIO;
3309         if (dev->xfer_shift == ATA_SHIFT_PIO)
3310                 dev->flags |= ATA_DFLAG_PIO;
3311 
3312         err_mask = ata_dev_set_xfermode(dev);
3313 
3314         if (err_mask & ~AC_ERR_DEV)
3315                 goto fail;
3316 
3317         /* revalidate */
3318         ehc->i.flags |= ATA_EHI_POST_SETMODE;
3319         rc = ata_dev_revalidate(dev, ATA_DEV_UNKNOWN, 0);
3320         ehc->i.flags &= ~ATA_EHI_POST_SETMODE;
3321         if (rc)
3322                 return rc;
3323 
3324         /* Old CFA may refuse this command, which is just fine */
3325         if (dev->xfer_shift == ATA_SHIFT_PIO && ata_id_is_cfa(dev->id))
3326                 ign_dev_err = 1;
3327 
3328         /* Some very old devices and some bad newer ones fail any kind of
3329            SET_XFERMODE request but support PIO0-2 timings and no IORDY */
3330         if (dev->xfer_shift == ATA_SHIFT_PIO && !ata_id_has_iordy(dev->id) &&
3331                         dev->pio_mode <= XFER_PIO_2)
3332                 ign_dev_err = 1;
3333 
3334         /* Early MWDMA devices do DMA but don't allow DMA mode setting.
3335            Don't fail an MWDMA0 set IFF the device indicates it is in MWDMA0 */
3336         if (dev->xfer_shift == ATA_SHIFT_MWDMA &&
3337             dev->dma_mode == XFER_MW_DMA_0 &&
3338             (dev->id[63] >> 8) & 1)
3339                 ign_dev_err = 1;
3340 
3341         /* if the device is actually configured correctly, ignore dev err */
3342         if (dev->xfer_mode == ata_xfer_mask2mode(ata_id_xfermask(dev->id)))
3343                 ign_dev_err = 1;
3344 
3345         if (err_mask & AC_ERR_DEV) {
3346                 if (!ign_dev_err)
3347                         goto fail;
3348                 else
3349                         dev_err_whine = " (device error ignored)";
3350         }
3351 
3352         DPRINTK("xfer_shift=%u, xfer_mode=0x%x\n",
3353                 dev->xfer_shift, (int)dev->xfer_mode);
3354 
3355         ata_dev_printk(dev, KERN_INFO, "configured for %s%s\n",
3356                        ata_mode_string(ata_xfer_mode2mask(dev->xfer_mode)),
3357                        dev_err_whine);
3358 
3359         return 0;
3360 
3361  fail:
3362         ata_dev_printk(dev, KERN_ERR, "failed to set xfermode "
3363                        "(err_mask=0x%x)\n", err_mask);
3364         return -EIO;
3365 }
3366 
3367 /**
3368  *      ata_do_set_mode - Program timings and issue SET FEATURES - XFER
3369  *      @link: link on which timings will be programmed
3370  *      @r_failed_dev: out parameter for failed device
3371  *
3372  *      Standard implementation of the function used to tune and set
3373  *      ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3374  *      ata_dev_set_mode() fails, pointer to the failing device is
3375  *      returned in @r_failed_dev.
3376  *
3377  *      LOCKING:
3378  *      PCI/etc. bus probe sem.
3379  *
3380  *      RETURNS:
3381  *      0 on success, negative errno otherwise
3382  */
3383 
3384 int ata_do_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3385 {
3386         struct ata_port *ap = link->ap;
3387         struct ata_device *dev;
3388         int rc = 0, used_dma = 0, found = 0;
3389 
3390         /* step 1: calculate xfer_mask */
3391         ata_link_for_each_dev(dev, link) {
3392                 unsigned long pio_mask, dma_mask;
3393                 unsigned int mode_mask;
3394 
3395                 if (!ata_dev_enabled(dev))
3396                         continue;
3397 
3398                 mode_mask = ATA_DMA_MASK_ATA;
3399                 if (dev->class == ATA_DEV_ATAPI)
3400                         mode_mask = ATA_DMA_MASK_ATAPI;
3401                 else if (ata_id_is_cfa(dev->id))
3402                         mode_mask = ATA_DMA_MASK_CFA;
3403 
3404                 ata_dev_xfermask(dev);
3405                 ata_force_xfermask(dev);
3406 
3407                 pio_mask = ata_pack_xfermask(dev->pio_mask, 0, 0);
3408                 dma_mask = ata_pack_xfermask(0, dev->mwdma_mask, dev->udma_mask);
3409 
3410                 if (libata_dma_mask & mode_mask)
3411                         dma_mask = ata_pack_xfermask(0, dev->mwdma_mask, dev->udma_mask);
3412                 else
3413                         dma_mask = 0;
3414 
3415                 dev->pio_mode = ata_xfer_mask2mode(pio_mask);
3416                 dev->dma_mode = ata_xfer_mask2mode(dma_mask);
3417 
3418                 found = 1;
3419                 if (dev->dma_mode != 0xff)
3420                         used_dma = 1;
3421         }
3422         if (!found)
3423                 goto out;
3424 
3425         /* step 2: always set host PIO timings */
3426         ata_link_for_each_dev(dev, link) {
3427                 if (!ata_dev_enabled(dev))
3428                         continue;
3429 
3430                 if (dev->pio_mode == 0xff) {
3431                         ata_dev_printk(dev, KERN_WARNING, "no PIO support\n");
3432                         rc = -EINVAL;
3433                         goto out;
3434                 }
3435 
3436                 dev->xfer_mode = dev->pio_mode;
3437                 dev->xfer_shift = ATA_SHIFT_PIO;
3438                 if (ap->ops->set_piomode)
3439                         ap->ops->set_piomode(ap, dev);
3440         }
3441 
3442         /* step 3: set host DMA timings */
3443         ata_link_for_each_dev(dev, link) {
3444                 if (!ata_dev_enabled(dev) || dev->dma_mode == 0xff)
3445                         continue;
3446 
3447                 dev->xfer_mode = dev->dma_mode;
3448                 dev->xfer_shift = ata_xfer_mode2shift(dev->dma_mode);
3449                 if (ap->ops->set_dmamode)
3450                         ap->ops->set_dmamode(ap, dev);
3451         }
3452 
3453         /* step 4: update devices' xfer mode */
3454         ata_link_for_each_dev(dev, link) {
3455                 /* don't update suspended devices' xfer mode */
3456                 if (!ata_dev_enabled(dev))
3457                         continue;
3458 
3459                 rc = ata_dev_set_mode(dev);
3460                 if (rc)
3461                         goto out;
3462         }
3463 
3464         /* Record simplex status. If we selected DMA then the other
3465          * host channels are not permitted to do so.
3466          */
3467         if (used_dma && (ap->host->flags & ATA_HOST_SIMPLEX))
3468                 ap->host->simplex_claimed = ap;
3469 
3470  out:
3471         if (rc)
3472                 *r_failed_dev = dev;
3473         return rc;
3474 }
3475 
3476 /**
3477  *      ata_tf_to_host - issue ATA taskfile to host controller
3478  *      @ap: port to which command is being issued
3479  *      @tf: ATA taskfile register set
3480  *
3481  *      Issues ATA taskfile register set to ATA host controller,
3482  *      with proper synchronization with interrupt handler and
3483  *      other threads.
3484  *
3485  *      LOCKING:
3486  *      spin_lock_irqsave(host lock)
3487  */
3488 
3489 static inline void ata_tf_to_host(struct ata_port *ap,
3490                                   const struct ata_taskfile *tf)
3491 {
3492         ap->ops->tf_load(ap, tf);
3493         ap->ops->exec_command(ap, tf);
3494 }
3495 
3496 /**
3497  *      ata_busy_sleep - sleep until BSY clears, or timeout
3498  *      @ap: port containing status register to be polled
3499  *      @tmout_pat: impatience timeout
3500  *      @tmout: overall timeout
3501  *
3502  *      Sleep until ATA Status register bit BSY clears,
3503  *      or a timeout occurs.
3504  *
3505  *      LOCKING:
3506  *      Kernel thread context (may sleep).
3507  *
3508  *      RETURNS:
3509  *      0 on success, -errno otherwise.
3510  */
3511 int ata_busy_sleep(struct ata_port *ap,
3512                    unsigned long tmout_pat, unsigned long tmout)
3513 {
3514         unsigned long timer_start, timeout;
3515         u8 status;
3516 
3517         status = ata_busy_wait(ap, ATA_BUSY, 300);
3518         timer_start = jiffies;
3519         timeout = timer_start + tmout_pat;
3520         while (status != 0xff && (status & ATA_BUSY) &&
3521                time_before(jiffies, timeout)) {
3522                 msleep(50);
3523                 status = ata_busy_wait(ap, ATA_BUSY, 3);
3524         }
3525 
3526         if (status != 0xff && (status & ATA_BUSY))
3527                 ata_port_printk(ap, KERN_WARNING,
3528                                 "port is slow to respond, please be patient "
3529                                 "(Status 0x%x)\n", status);
3530 
3531         timeout = timer_start + tmout;
3532         while (status != 0xff && (status & ATA_BUSY) &&
3533                time_before(jiffies, timeout)) {
3534                 msleep(50);
3535                 status = ata_chk_status(ap);
3536         }
3537 
3538         if (status == 0xff)
3539                 return -ENODEV;
3540 
3541         if (status & ATA_BUSY) {
3542                 ata_port_printk(ap, KERN_ERR, "port failed to respond "
3543                                 "(%lu secs, Status 0x%x)\n",
3544                                 tmout / HZ, status);
3545                 return -EBUSY;
3546         }
3547 
3548         return 0;
3549 }
3550 
3551 /**
3552  *      ata_wait_after_reset - wait before checking status after reset
3553  *      @ap: port containing status register to be polled
3554  *      @deadline: deadline jiffies for the operation
3555  *
3556  *      After reset, we need to pause a while before reading status.
3557  *      Also, certain combination of controller and device report 0xff
3558  *      for some duration (e.g. until SATA PHY is up and running)
3559  *      which is interpreted as empty port in ATA world.  This
3560  *      function also waits for such devices to get out of 0xff
3561  *      status.
3562  *
3563  *      LOCKING:
3564  *      Kernel thread context (may sleep).
3565  */
3566 void ata_wait_after_reset(struct ata_port *ap, unsigned long deadline)
3567 {
3568         unsigned long until = jiffies + ATA_TMOUT_FF_WAIT;
3569 
3570         if (time_before(until, deadline))
3571                 deadline = until;
3572 
3573         /* Spec mandates ">= 2ms" before checking status.  We wait
3574          * 150ms, because that was the magic delay used for ATAPI
3575          * devices in Hale Landis's ATADRVR, for the period of time
3576          * between when the ATA command register is written, and then
3577          * status is checked.  Because waiting for "a while" before
3578          * checking status is fine, post SRST, we perform this magic
3579          * delay here as well.
3580          *
3581          * Old drivers/ide uses the 2mS rule and then waits for ready.
3582          */
3583         msleep(150);
3584 
3585         /* Wait for 0xff to clear.  Some SATA devices take a long time
3586          * to clear 0xff after reset.  For example, HHD424020F7SV00
3587          * iVDR needs >= 800ms while.  Quantum GoVault needs even more
3588          * than that.
3589          *
3590          * Note that some PATA controllers (pata_ali) explode if
3591          * status register is read more than once when there's no
3592          * device attached.
3593          */
3594         if (ap->flags & ATA_FLAG_SATA) {
3595                 while (1) {
3596                         u8 status = ata_chk_status(ap);
3597 
3598                         if (status != 0xff || time_after(jiffies, deadline))
3599                                 return;
3600 
3601                         msleep(50);
3602                 }
3603         }
3604 }
3605 
3606 /**
3607  *      ata_wait_ready - sleep until BSY clears, or timeout
3608  *      @ap: port containing status register to be polled
3609  *      @deadline: deadline jiffies for the operation
3610  *
3611  *      Sleep until ATA Status register bit BSY clears, or timeout
3612  *      occurs.
3613  *
3614  *      LOCKING:
3615  *      Kernel thread context (may sleep).
3616  *
3617  *      RETURNS:
3618  *      0 on success, -errno otherwise.
3619  */
3620 int ata_wait_ready(struct ata_port *ap, unsigned long deadline)
3621 {
3622         unsigned long start = jiffies;
3623         int warned = 0;
3624 
3625         while (1) {
3626                 u8 status = ata_chk_status(ap);
3627                 unsigned long now = jiffies;
3628 
3629                 if (!(status & ATA_BUSY))
3630                         return 0;
3631                 if (!ata_link_online(&ap->link) && status == 0xff)
3632                         return -ENODEV;
3633                 if (time_after(now, deadline))
3634                         return -EBUSY;
3635 
3636                 if (!warned && time_after(now, start + 5 * HZ) &&
3637                     (deadline - now > 3 * HZ)) {
3638                         ata_port_printk(ap, KERN_WARNING,
3639                                 "port is slow to respond, please be patient "
3640                                 "(Status 0x%x)\n", status);
3641                         warned = 1;
3642                 }
3643 
3644                 msleep(50);
3645         }
3646 }
3647 
3648 static int ata_bus_post_reset(struct ata_port *ap, unsigned int devmask,
3649                               unsigned long deadline)
3650 {
3651         struct ata_ioports *ioaddr = &ap->ioaddr;
3652         unsigned int dev0 = devmask & (1 << 0);
3653         unsigned int dev1 = devmask & (1 << 1);
3654         int rc, ret = 0;
3655 
3656         /* if device 0 was found in ata_devchk, wait for its
3657          * BSY bit to clear
3658          */
3659         if (dev0) {
3660                 rc = ata_wait_ready(ap, deadline);
3661                 if (rc) {
3662                         if (rc != -ENODEV)
3663                                 return rc;
3664                         ret = rc;
3665                 }
3666         }
3667 
3668         /* if device 1 was found in ata_devchk, wait for register
3669          * access briefly, then wait for BSY to clear.
3670          */
3671         if (dev1) {
3672                 int i;
3673 
3674                 ap->ops->dev_select(ap, 1);
3675 
3676                 /* Wait for register access.  Some ATAPI devices fail
3677                  * to set nsect/lbal after reset, so don't waste too
3678                  * much time on it.  We're gonna wait for !BSY anyway.
3679                  */
3680                 for (i = 0; i < 2; i++) {
3681                         u8 nsect, lbal;
3682 
3683                         nsect = ioread8(ioaddr->nsect_addr);
3684                         lbal = ioread8(ioaddr->lbal_addr);
3685                         if ((nsect == 1) && (lbal == 1))
3686                                 break;
3687                         msleep(50);     /* give drive a breather */
3688                 }
3689 
3690                 rc = ata_wait_ready(ap, deadline);
3691                 if (rc) {
3692                         if (rc != -ENODEV)
3693                                 return rc;
3694                         ret = rc;
3695                 }
3696         }
3697 
3698         /* is all this really necessary? */
3699         ap->ops->dev_select(ap, 0);
3700         if (dev1)
3701                 ap->ops->dev_select(ap, 1);
3702         if (dev0)
3703                 ap->ops->dev_select(ap, 0);
3704 
3705         return ret;
3706 }
3707 
3708 static int ata_bus_softreset(struct ata_port *ap, unsigned int devmask,
3709                              unsigned long deadline)
3710 {
3711         struct ata_ioports *ioaddr = &ap->ioaddr;
3712 
3713         DPRINTK("ata%u: bus reset via SRST\n", ap->print_id);
3714 
3715         /* software reset.  causes dev0 to be selected */
3716         iowrite8(ap->ctl, ioaddr->ctl_addr);
3717         udelay(20);     /* FIXME: flush */
3718         iowrite8(ap->ctl | ATA_SRST, ioaddr->ctl_addr);
3719         udelay(20);     /* FIXME: flush */
3720         iowrite8(ap->ctl, ioaddr->ctl_addr);
3721 
3722         /* wait a while before checking status */
3723         ata_wait_after_reset(ap, deadline);
3724 
3725         /* Before we perform post reset processing we want to see if
3726          * the bus shows 0xFF because the odd clown forgets the D7
3727          * pulldown resistor.
3728          */
3729         if (ata_chk_status(ap) == 0xFF)
3730                 return -ENODEV;
3731 
3732         return ata_bus_post_reset(ap, devmask, deadline);
3733 }
3734 
3735 /**
3736  *      ata_bus_reset - reset host port and associated ATA channel
3737  *      @ap: port to reset
3738  *
3739  *      This is typically the first time we actually start issuing
3740  *      commands to the ATA channel.  We wait for BSY to clear, then
3741  *      issue EXECUTE DEVICE DIAGNOSTIC command, polling for its
3742  *      result.  Determine what devices, if any, are on the channel
3743  *      by looking at the device 0/1 error register.  Look at the signature
3744  *      stored in each device's taskfile registers, to determine if
3745  *      the device is ATA or ATAPI.
3746  *
3747  *      LOCKING:
3748  *      PCI/etc. bus probe sem.
3749  *      Obtains host lock.
3750  *
3751  *      SIDE EFFECTS:
3752  *      Sets ATA_FLAG_DISABLED if bus reset fails.
3753  */
3754 
3755 void ata_bus_reset(struct ata_port *ap)
3756 {
3757         struct ata_device *device = ap->link.device;
3758         struct ata_ioports *ioaddr = &ap->ioaddr;
3759         unsigned int slave_possible = ap->flags & ATA_FLAG_SLAVE_POSS;
3760         u8 err;
3761         unsigned int dev0, dev1 = 0, devmask = 0;
3762         int rc;
3763 
3764         DPRINTK("ENTER, host %u, port %u\n", ap->print_id, ap->port_no);
3765 
3766         /* determine if device 0/1 are present */
3767         if (ap->flags & ATA_FLAG_SATA_RESET)
3768                 dev0 = 1;
3769         else {
3770                 dev0 = ata_devchk(ap, 0);
3771                 if (slave_possible)
3772                         dev1 = ata_devchk(ap, 1);
3773         }
3774 
3775         if (dev0)
3776                 devmask |= (1 << 0);
3777         if (dev1)
3778                 devmask |= (1 << 1);
3779 
3780         /* select device 0 again */
3781         ap->ops->dev_select(ap, 0);
3782 
3783         /* issue bus reset */
3784         if (ap->flags & ATA_FLAG_SRST) {
3785                 rc = ata_bus_softreset(ap, devmask, jiffies + 40 * HZ);
3786                 if (rc && rc != -ENODEV)
3787                         goto err_out;
3788         }
3789 
3790         /*
3791          * determine by signature whether we have ATA or ATAPI devices
3792          */
3793         device[0].class = ata_dev_try_classify(&device[0], dev0, &err);
3794         if ((slave_possible) && (err != 0x81))
3795                 device[1].class = ata_dev_try_classify(&device[1], dev1, &err);
3796 
3797         /* is double-select really necessary? */
3798         if (device[1].class != ATA_DEV_NONE)
3799                 ap->ops->dev_select(ap, 1);
3800         if (device[0].class != ATA_DEV_NONE)
3801                 ap->ops->dev_select(ap, 0);
3802 
3803         /* if no devices were detected, disable this port */
3804         if ((device[0].class == ATA_DEV_NONE) &&
3805             (device[1].class == ATA_DEV_NONE))
3806                 goto err_out;
3807 
3808         if (ap->flags & (ATA_FLAG_SATA_RESET | ATA_FLAG_SRST)) {
3809                 /* set up device control for ATA_FLAG_SATA_RESET */
3810                 iowrite8(ap->ctl, ioaddr->ctl_addr);
3811         }
3812 
3813         DPRINTK("EXIT\n");
3814         return;
3815 
3816 err_out:
3817         ata_port_printk(ap, KERN_ERR, "disabling port\n");
3818         ata_port_disable(ap);
3819 
3820         DPRINTK("EXIT\n");
3821 }
3822 
3823 /**
3824  *      sata_link_debounce - debounce SATA phy status
3825  *      @link: ATA link to debounce SATA phy status for
3826  *      @params: timing parameters { interval, duratinon, timeout } in msec
3827  *      @deadline: deadline jiffies for the operation
3828  *
3829 *       Make sure SStatus of @link reaches stable state, determined by
3830  *      holding the same value where DET is not 1 for @duration polled
3831  *      every @interval, before @timeout.  Timeout constraints the
3832  *      beginning of the stable state.  Because DET gets stuck at 1 on
3833  *      some controllers after hot unplugging, this functions waits
3834  *      until timeout then returns 0 if DET is stable at 1.
3835  *
3836  *      @timeout is further limited by @deadline.  The sooner of the
3837  *      two is used.
3838  *
3839  *      LOCKING:
3840  *      Kernel thread context (may sleep)
3841  *
3842  *      RETURNS:
3843  *      0 on success, -errno on failure.
3844  */
3845 int sata_link_debounce(struct ata_link *link, const unsigned long *params,
3846                        unsigned long deadline)
3847 {
3848         unsigned long interval_msec = params[0];
3849         unsigned long duration = msecs_to_jiffies(params[1]);
3850         unsigned long last_jiffies, t;
3851         u32 last, cur;
3852         int rc;
3853 
3854         t = jiffies + msecs_to_jiffies(params[2]);
3855         if (time_before(t, deadline))
3856                 deadline = t;
3857 
3858         if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3859                 return rc;
3860         cur &= 0xf;
3861 
3862         last = cur;
3863         last_jiffies = jiffies;
3864 
3865         while (1) {
3866                 msleep(interval_msec);
3867                 if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3868                         return rc;
3869                 cur &= 0xf;
3870 
3871                 /* DET stable? */
3872                 if (cur == last) {
3873                         if (cur == 1 && time_before(jiffies, deadline))
3874                                 continue;
3875                         if (time_after(jiffies, last_jiffies + duration))
3876                                 return 0;
3877                         continue;
3878                 }
3879 
3880                 /* unstable, start over */
3881                 last = cur;
3882                 last_jiffies = jiffies;
3883 
3884                 /* Check deadline.  If debouncing failed, return
3885                  * -EPIPE to tell upper layer to lower link speed.
3886                  */
3887                 if (time_after(jiffies, deadline))
3888                         return -EPIPE;
3889         }
3890 }
3891 
3892 /**
3893  *      sata_link_resume - resume SATA link
3894  *      @link: ATA link to resume SATA
3895  *      @params: timing parameters { interval, duratinon, timeout } in msec
3896  *      @deadline: deadline jiffies for the operation
3897  *
3898  *      Resume SATA phy @link and debounce it.
3899  *
3900  *      LOCKING:
3901  *      Kernel thread context (may sleep)
3902  *
3903  *      RETURNS:
3904  *      0 on success, -errno on failure.
3905  */
3906 int sata_link_resume(struct ata_link *link, const unsigned long *params,
3907                      unsigned long deadline)
3908 {
3909         u32 scontrol;
3910         int rc;
3911 
3912         if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3913                 return rc;
3914 
3915         scontrol = (scontrol & 0x0f0) | 0x300;
3916 
3917         if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3918                 return rc;
3919 
3920         /* Some PHYs react badly if SStatus is pounded immediately
3921          * after resuming.  Delay 200ms before debouncing.
3922          */
3923         msleep(200);
3924 
3925         return sata_link_debounce(link, params, deadline);
3926 }
3927 
3928 /**
3929  *      ata_std_prereset - prepare for reset
3930  *      @link: ATA link to be reset
3931  *      @deadline: deadline jiffies for the operation
3932  *
3933  *      @link is about to be reset.  Initialize it.  Failure from
3934  *      prereset makes libata abort whole reset sequence and give up
3935  *      that port, so prereset should be best-effort.  It does its
3936  *      best to prepare for reset sequence but if things go wrong, it
3937  *      should just whine, not fail.
3938  *
3939  *      LOCKING:
3940  *      Kernel thread context (may sleep)
3941  *
3942  *      RETURNS:
3943  *      0 on success, -errno otherwise.
3944  */
3945 int ata_std_prereset(struct ata_link *link, unsigned long deadline)
3946 {
3947         struct ata_port *ap = link->ap;
3948         struct ata_eh_context *ehc = &link->eh_context;
3949         const unsigned long *timing = sata_ehc_deb_timing(ehc);
3950         u32 sstatus;
3951         int rc;
3952 
3953         /* handle link resume */
3954         if ((ehc->i.flags & ATA_EHI_RESUME_LINK) &&
3955             (link->flags & ATA_LFLAG_HRST_TO_RESUME))
3956                 ehc->i.action |= ATA_EH_HARDRESET;
3957 
3958         /* Some PMPs don't work with only SRST, force hardreset if PMP
3959          * is supported.
3960          */
3961         if (ap->flags & ATA_FLAG_PMP)
3962                 ehc->i.action |= ATA_EH_HARDRESET;
3963 
3964         /* if link powersave is on, force hardreset */
3965         if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0) {
3966                 u8 ipm = sstatus >> 8;
3967 
3968                 if (ipm == 2 || ipm == 6) {
3969                         ata_link_printk(link, KERN_INFO, "link in powersave "
3970                                 "mode (ipm=%d), forcing hardreset\n", ipm);
3971                         ehc->i.action |= ATA_EH_HARDRESET;
3972                 }
3973         }
3974 
3975         /* if we're about to do hardreset, nothing more to do */
3976         if (ehc->i.action & ATA_EH_HARDRESET)
3977                 return 0;
3978 
3979         /* if SATA, resume link */
3980         if (ap->flags & ATA_FLAG_SATA) {
3981                 rc = sata_link_resume(link, timing, deadline);
3982                 /* whine about phy resume failure but proceed */
3983                 if (rc && rc != -EOPNOTSUPP)
3984                         ata_link_printk(link, KERN_WARNING, "failed to resume "
3985                                         "link for reset (errno=%d)\n", rc);
3986         }
3987 
3988         /* Wait for !BSY if the controller can wait for the first D2H
3989          * Reg FIS and we don't know that no device is attached.
3990          */
3991         if (!(link->flags & ATA_LFLAG_SKIP_D2H_BSY) && !ata_link_offline(link)) {
3992                 rc = ata_wait_ready(ap, deadline);
3993                 if (rc && rc != -ENODEV) {
3994                         ata_link_printk(link, KERN_WARNING, "device not ready "
3995                                         "(errno=%d), forcing hardreset\n", rc);
3996                         ehc->i.action |= ATA_EH_HARDRESET;
3997                 }
3998         }
3999 
4000         return 0;
4001 }
4002 
4003 /**
4004  *      ata_std_softreset - reset host port via ATA SRST
4005  *      @link: ATA link to reset
4006  *      @classes: resulting classes of attached devices
4007  *      @deadline: deadline jiffies for the operation
4008  *
4009  *      Reset host port using ATA SRST.
4010  *
4011  *      LOCKING:
4012  *      Kernel thread context (may sleep)
4013  *
4014  *      RETURNS:
4015  *      0 on success, -errno otherwise.
4016  */
4017 int ata_std_softreset(struct ata_link *link, unsigned int *classes,
4018                       unsigned long deadline)
4019 {
4020         struct ata_port *ap = link->ap;
4021         unsigned int slave_possible = ap->flags & ATA_FLAG_SLAVE_POSS;
4022         unsigned int devmask = 0;
4023         int rc;
4024         u8 err;
4025 
4026         DPRINTK("ENTER\n");
4027 
4028         if (ata_link_offline(link)) {
4029                 classes[0] = ATA_DEV_NONE;
4030                 goto out;
4031         }
4032 
4033         /* determine if device 0/1 are present */
4034         if (ata_devchk(ap, 0))
4035                 devmask |= (1 << 0);
4036         if (slave_possible && ata_devchk(ap, 1))
4037                 devmask |= (1 << 1);
4038 
4039         /* select device 0 again */
4040         ap->ops->dev_select(ap, 0);
4041 
4042         /* issue bus reset */
4043         DPRINTK("about to softreset, devmask=%x\n", devmask);
4044         rc = ata_bus_softreset(ap, devmask, deadline);
4045         /* if link is occupied, -ENODEV too is an error */
4046         if (rc && (rc != -ENODEV || sata_scr_valid(link))) {
4047                 ata_link_printk(link, KERN_ERR, "SRST failed (errno=%d)\n", rc);
4048                 return rc;
4049         }
4050 
4051         /* determine by signature whether we have ATA or ATAPI devices */
4052         classes[0] = ata_dev_try_classify(&link->device[0],
4053                                           devmask & (1 << 0), &err);
4054         if (slave_possible && err != 0x81)
4055                 classes[1] = ata_dev_try_classify(&link->device[1],
4056                                                   devmask & (1 << 1), &err);
4057 
4058  out:
4059         DPRINTK("EXIT, classes[0]=%u [1]=%u\n", classes[0], classes[1]);
4060         return 0;
4061 }
4062 
4063 /**
4064  *      sata_link_hardreset - reset link via SATA phy reset
4065  *      @link: link to reset
4066  *      @timing: timing parameters { interval, duratinon, timeout } in msec
4067  *      @deadline: deadline jiffies for the operation
4068  *
4069  *      SATA phy-reset @link using DET bits of SControl register.
4070  *
4071  *      LOCKING:
4072  *      Kernel thread context (may sleep)
4073  *
4074  *      RETURNS:
4075  *      0 on success, -errno otherwise.
4076  */
4077 int sata_link_hardreset(struct ata_link *link, const unsigned long *timing,
4078                         unsigned long deadline)
4079 {
4080         u32 scontrol;
4081         int rc;
4082 
4083         DPRINTK("ENTER\n");
4084 
4085         if (sata_set_spd_needed(link)) {
4086                 /* SATA spec says nothing about how to reconfigure
4087                  * spd.  To be on the safe side, turn off phy during
4088                  * reconfiguration.  This works for at least ICH7 AHCI
4089                  * and Sil3124.
4090                  */
4091                 if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
4092                         goto out;
4093 
4094                 scontrol = (scontrol & 0x0f0) | 0x304;
4095 
4096                 if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
4097                         goto out;
4098 
4099                 sata_set_spd(link);
4100         }
4101 
4102         /* issue phy wake/reset */
4103         if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
4104                 goto out;
4105 
4106         scontrol = (scontrol & 0x0f0) | 0x301;
4107 
4108         if ((rc = sata_scr_write_flush(link, SCR_CONTROL, scontrol)))
4109                 goto out;
4110 
4111         /* Couldn't find anything in SATA I/II specs, but AHCI-1.1
4112          * 10.4.2 says at least 1 ms.
4113          */
4114         msleep(1);
4115 
4116         /* bring link back */
4117         rc = sata_link_resume(link, timing, deadline);
4118  out:
4119         DPRINTK("EXIT, rc=%d\n", rc);
4120         return rc;
4121 }
4122 
4123 /**
4124  *      sata_std_hardreset - reset host port via SATA phy reset
4125  *      @link: link to reset
4126  *      @class: resulting class of attached device
4127  *      @deadline: deadline jiffies for the operation
4128  *
4129  *      SATA phy-reset host port using DET bits of SControl register,
4130  *      wait for !BSY and classify the attached device.
4131  *
4132  *      LOCKING:
4133  *      Kernel thread context (may sleep)
4134  *
4135  *      RETURNS:
4136  *      0 on success, -errno otherwise.
4137  */
4138 int sata_std_hardreset(struct ata_link *link, unsigned int *class,
4139                        unsigned long deadline)
4140 {
4141         struct ata_port *ap = link->ap;
4142         const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
4143         int rc;
4144 
4145         DPRINTK("ENTER\n");
4146 
4147         /* do hardreset */
4148         rc = sata_link_hardreset(link, timing, deadline);
4149         if (rc) {
4150                 ata_link_printk(link, KERN_ERR,
4151                                 "COMRESET failed (errno=%d)\n", rc);
4152                 return rc;
4153         }
4154 
4155         /* TODO: phy layer with polling, timeouts, etc. */
4156         if (ata_link_offline(link)) {
4157                 *class = ATA_DEV_NONE;
4158                 DPRINTK("EXIT, link offline\n");
4159                 return 0;
4160         }
4161 
4162         /* wait a while before checking status */
4163         ata_wait_after_reset(ap, deadline);
4164 
4165         /* If PMP is supported, we have to do follow-up SRST.  Note
4166          * that some PMPs don't send D2H Reg FIS after hardreset at
4167          * all if the first port is empty.  Wait for it just for a
4168          * second and request follow-up SRST.
4169          */
4170         if (ap->flags & ATA_FLAG_PMP) {
4171                 ata_wait_ready(ap, jiffies + HZ);
4172                 return -EAGAIN;
4173         }
4174 
4175         rc = ata_wait_ready(ap, deadline);
4176         /* link occupied, -ENODEV too is an error */
4177         if (rc) {
4178                 ata_link_printk(link, KERN_ERR,
4179                                 "COMRESET failed (errno=%d)\n", rc);
4180                 return rc;
4181         }
4182 
4183         ap->ops->dev_select(ap, 0);     /* probably unnecessary */
4184 
4185         *class = ata_dev_try_classify(link->device, 1, NULL);
4186 
4187         DPRINTK("EXIT, class=%u\n", *class);
4188         return 0;
4189 }
4190 
4191 /**
4192  *      ata_std_postreset - standard postreset callback
4193  *      @link: the target ata_link
4194  *      @classes: classes of attached devices
4195  *
4196  *      This function is invoked after a successful reset.  Note that
4197  *      the device might have been reset more than once using
4198  *      different reset methods before postreset is invoked.
4199  *
4200  *      LOCKING:
4201  *      Kernel thread context (may sleep)
4202  */
4203 void ata_std_postreset(struct ata_link *link, unsigned int *classes)
4204 {
4205         struct ata_port *ap = link->ap;
4206         u32 serror;
4207 
4208         DPRINTK("ENTER\n");
4209 
4210         /* print link status */
4211         sata_print_link_status(link);
4212 
4213         /* clear SError */
4214         if (sata_scr_read(link, SCR_ERROR, &serror) == 0)
4215                 sata_scr_write(link, SCR_ERROR, serror);
4216         link->eh_info.serror = 0;
4217 
4218         /* is double-select really necessary? */
4219         if (classes[0] != ATA_DEV_NONE)
4220                 ap->ops->dev_select(ap, 1);
4221         if (classes[1] != ATA_DEV_NONE)
4222                 ap->ops->dev_select(ap, 0);
4223 
4224         /* bail out if no device is present */
4225         if (classes[0] == ATA_DEV_NONE && classes[1] == ATA_DEV_NONE) {
4226                 DPRINTK("EXIT, no device\n");
4227                 return;
4228         }
4229 
4230         /* set up device control */
4231         if (ap->ioaddr.ctl_addr)
4232                 iowrite8(ap->ctl, ap->ioaddr.ctl_addr);
4233 
4234         DPRINTK("EXIT\n");
4235 }
4236 
4237 /**
4238  *      ata_dev_same_device - Determine whether new ID matches configured device
4239  *      @dev: device to compare against
4240  *      @new_class: class of the new device
4241  *      @new_id: IDENTIFY page of the new device
4242  *
4243  *      Compare @new_class and @new_id against @dev and determine
4244  *      whether @dev is the device indicated by @new_class and
4245  *      @new_id.
4246  *
4247  *      LOCKING:
4248  *      None.
4249  *
4250  *      RETURNS:
4251  *      1 if @dev matches @new_class and @new_id, 0 otherwise.
4252  */
4253 static int ata_dev_same_device(struct ata_device *dev, unsigned int new_class,
4254                                const u16 *new_id)
4255 {
4256         const u16 *old_id = dev->id;
4257         unsigned char model[2][ATA_ID_PROD_LEN + 1];
4258         unsigned char serial[2][ATA_ID_SERNO_LEN + 1];
4259 
4260         if (dev->class != new_class) {
4261                 ata_dev_printk(dev, KERN_INFO, "class mismatch %d != %d\n",
4262                                dev->class, new_class);
4263                 return 0;
4264         }
4265 
4266         ata_id_c_string(old_id, model[0], ATA_ID_PROD, sizeof(model[0]));
4267         ata_id_c_string(new_id, model[1], ATA_ID_PROD, sizeof(model[1]));
4268         ata_id_c_string(old_id, serial[0], ATA_ID_SERNO, sizeof(serial[0]));
4269         ata_id_c_string(new_id, serial[1], ATA_ID_SERNO, sizeof(serial[1]));
4270 
4271         if (strcmp(model[0], model[1])) {
4272                 ata_dev_printk(dev, KERN_INFO, "model number mismatch "
4273                                "'%s' != '%s'\n", model[0], model[1]);
4274                 return 0;
4275         }
4276 
4277         if (strcmp(serial[0], serial[1])) {
4278                 ata_dev_printk(dev, KERN_INFO, "serial number mismatch "
4279                                "'%s' != '%s'\n", serial[0], serial[1]);
4280                 return 0;
4281         }
4282 
4283         return 1;
4284 }
4285 
4286 /**
4287  *      ata_dev_reread_id - Re-read IDENTIFY data
4288  *      @dev: target ATA device
4289  *      @readid_flags: read ID flags
4290  *
4291  *      Re-read IDENTIFY page and make sure @dev is still attached to
4292  *      the port.
4293  *
4294  *      LOCKING:
4295  *      Kernel thread context (may sleep)
4296  *
4297  *      RETURNS:
4298  *      0 on success, negative errno otherwise
4299  */
4300 int ata_dev_reread_id(struct ata_device *dev, unsigned int readid_flags)
4301 {
4302         unsigned int class = dev->class;
4303         u16 *id = (void *)dev->link->ap->sector_buf;
4304         int rc;
4305 
4306         /* read ID data */
4307         rc = ata_dev_read_id(dev, &class, readid_flags, id);
4308         if (rc)
4309                 return rc;
4310 
4311         /* is the device still there? */
4312         if (!ata_dev_same_device(dev, class, id))
4313                 return -ENODEV;
4314 
4315         memcpy(dev->id, id, sizeof(id[0]) * ATA_ID_WORDS);
4316         return 0;
4317 }
4318 
4319 /**
4320  *      ata_dev_revalidate - Revalidate ATA device
4321  *      @dev: device to revalidate
4322  *      @new_class: new class code
4323  *      @readid_flags: read ID flags
4324  *
4325  *      Re-read IDENTIFY page, make sure @dev is still attached to the
4326  *      port and reconfigure it according to the new IDENTIFY page.
4327  *
4328  *      LOCKING:
4329  *      Kernel thread context (may sleep)
4330  *
4331  *      RETURNS:
4332  *      0 on success, negative errno otherwise
4333  */
4334 int ata_dev_revalidate(struct ata_device *dev, unsigned int new_class,
4335                        unsigned int readid_flags)
4336 {
4337         u64 n_sectors = dev->n_sectors;
4338         int rc;
4339 
4340         if (!ata_dev_enabled(dev))
4341                 return -ENODEV;
4342 
4343         /* fail early if !ATA && !ATAPI to avoid issuing [P]IDENTIFY to PMP */
4344         if (ata_class_enabled(new_class) &&
4345             new_class != ATA_DEV_ATA && new_class != ATA_DEV_ATAPI) {
4346                 ata_dev_printk(dev, KERN_INFO, "class mismatch %u != %u\n",
4347                                dev->class, new_class);
4348                 rc = -ENODEV;
4349                 goto fail;
4350         }
4351 
4352         /* re-read ID */
4353         rc = ata_dev_reread_id(dev, readid_flags);
4354         if (rc)
4355                 goto fail;
4356 
4357         /* configure device according to the new ID */
4358         rc = ata_dev_configure(dev);
4359         if (rc)
4360                 goto fail;
4361 
4362         /* verify n_sectors hasn't changed */
4363         if (dev->class == ATA_DEV_ATA && n_sectors &&
4364             dev->n_sectors != n_sectors) {
4365                 ata_dev_printk(dev, KERN_INFO, "n_sectors mismatch "
4366                                "%llu != %llu\n",
4367                                (unsigned long long)n_sectors,
4368                                (unsigned long long)dev->n_sectors);
4369 
4370                 /* restore original n_sectors */
4371                 dev->n_sectors = n_sectors;
4372 
4373                 rc = -ENODEV;
4374                 goto fail;
4375         }
4376 
4377         return 0;
4378 
4379  fail:
4380         ata_dev_printk(dev, KERN_ERR, "revalidation failed (errno=%d)\n", rc);
4381         return rc;
4382 }
4383 
4384 struct ata_blacklist_entry {
4385         const char *model_num;
4386         const char *model_rev;
4387         unsigned long horkage;
4388 };
4389 
4390 static const struct ata_blacklist_entry ata_device_blacklist [] = {
4391         /* Devices with DMA related problems under Linux */
4392         { "WDC AC11000H",       NULL,           ATA_HORKAGE_NODMA },
4393         { "WDC AC22100H",       NULL,           ATA_HORKAGE_NODMA },
4394         { "WDC AC32500H",       NULL,           ATA_HORKAGE_NODMA },
4395         { "WDC AC33100H",       NULL,           ATA_HORKAGE_NODMA },
4396         { "WDC AC31600H",       NULL,           ATA_HORKAGE_NODMA },
4397         { "WDC AC32100H",       "24.09P07",     ATA_HORKAGE_NODMA },
4398         { "WDC AC23200L",       "21.10N21",     ATA_HORKAGE_NODMA },
4399         { "Compaq CRD-8241B",   NULL,           ATA_HORKAGE_NODMA },
4400         { "CRD-8400B",          NULL,           ATA_HORKAGE_NODMA },
4401         { "CRD-8480B",          NULL,           ATA_HORKAGE_NODMA },
4402         { "CRD-8482B",          NULL,           ATA_HORKAGE_NODMA },
4403         { "CRD-84",             NULL,           ATA_HORKAGE_NODMA },
4404         { "SanDisk SDP3B",      NULL,           ATA_HORKAGE_NODMA },
4405         { "SanDisk SDP3B-64",   NULL,           ATA_HORKAGE_NODMA },
4406         { "SANYO CD-ROM CRD",   NULL,           ATA_HORKAGE_NODMA },
4407         { "HITACHI CDR-8",      NULL,           ATA_HORKAGE_NODMA },
4408         { "HITACHI CDR-8335",   NULL,           ATA_HORKAGE_NODMA },
4409         { "HITACHI CDR-8435",   NULL,           ATA_HORKAGE_NODMA },
4410         { "Toshiba CD-ROM XM-6202B", NULL,      ATA_HORKAGE_NODMA },
4411         { "TOSHIBA CD-ROM XM-1702BC", NULL,     ATA_HORKAGE_NODMA },
4412         { "CD-532E-A",          NULL,           ATA_HORKAGE_NODMA },
4413         { "E-IDE CD-ROM CR-840",NULL,           ATA_HORKAGE_NODMA },
4414         { "CD-ROM Drive/F5A",   NULL,           ATA_HORKAGE_NODMA },
4415         { "WPI CDD-820",        NULL,           ATA_HORKAGE_NODMA },
4416         { "SAMSUNG CD-ROM SC-148C", NULL,       ATA_HORKAGE_NODMA },
4417         { "SAMSUNG CD-ROM SC",  NULL,           ATA_HORKAGE_NODMA },
4418         { "ATAPI CD-ROM DRIVE 40X MAXIMUM",NULL,ATA_HORKAGE_NODMA },
4419         { "_NEC DV5800A",       NULL,           ATA_HORKAGE_NODMA },
4420         { "SAMSUNG CD-ROM SN-124", "N001",      ATA_HORKAGE_NODMA },
4421         { "Seagate STT20000A", NULL,            ATA_HORKAGE_NODMA },
4422         /* Odd clown on sil3726/4726 PMPs */
4423         { "Config  Disk",       NULL,           ATA_HORKAGE_NODMA |
4424                                                 ATA_HORKAGE_SKIP_PM },
4425 
4426         /* Weird ATAPI devices */
4427         { "TORiSAN DVD-ROM DRD-N216", NULL,     ATA_HORKAGE_MAX_SEC_128 },
4428 
4429         /* Devices we expect to fail diagnostics */
4430 
4431         /* Devices where NCQ should be avoided */
4432         /* NCQ is slow */
4433         { "WDC WD740ADFD-00",   NULL,           ATA_HORKAGE_NONCQ },
4434         { "WDC WD740ADFD-00NLR1", NULL,         ATA_HORKAGE_NONCQ, },
4435         /* http://thread.gmane.org/gmane.linux.ide/14907 */
4436         { "FUJITSU MHT2060BH",  NULL,           ATA_HORKAGE_NONCQ },
4437         /* NCQ is broken */
4438         { "Maxtor *",           "BANC*",        ATA_HORKAGE_NONCQ },
4439         { "Maxtor 7V300F0",     "VA111630",     ATA_HORKAGE_NONCQ },
4440         { "ST380817AS",         "3.42",         ATA_HORKAGE_NONCQ },
4441         { "ST3160023AS",        "3.42",         ATA_HORKAGE_NONCQ },
4442 
4443         /* Blacklist entries taken from Silicon Image 3124/3132
4444            Windows driver .inf file - also several Linux problem reports */
4445         { "HTS541060G9SA00",    "MB3OC60D",     ATA_HORKAGE_NONCQ, },
4446         { "HTS541080G9SA00",    "MB4OC60D",     ATA_HORKAGE_NONCQ, },
4447         { "HTS541010G9SA00",    "MBZOC60D",     ATA_HORKAGE_NONCQ, },
4448 
4449         /* devices which puke on READ_NATIVE_MAX */
4450         { "HDS724040KLSA80",    "KFAOA20N",     ATA_HORKAGE_BROKEN_HPA, },
4451         { "WDC WD3200JD-00KLB0", "WD-WCAMR1130137", ATA_HORKAGE_BROKEN_HPA },
4452         { "WDC WD2500JD-00HBB0", "WD-WMAL71490727", ATA_HORKAGE_BROKEN_HPA },
4453         { "MAXTOR 6L080L4",     "A93.0500",     ATA_HORKAGE_BROKEN_HPA },
4454 
4455         /* Devices which report 1 sector over size HPA */
4456         { "ST340823A",          NULL,           ATA_HORKAGE_HPA_SIZE, },
4457         { "ST320413A",          NULL,           ATA_HORKAGE_HPA_SIZE, },
4458         { "ST310211A",          NULL,           ATA_HORKAGE_HPA_SIZE, },
4459 
4460         /* Devices which get the IVB wrong */
4461         { "QUANTUM FIREBALLlct10 05", "A03.0900", ATA_HORKAGE_IVB, },
4462         { "TSSTcorp CDDVDW SH-S202J", "SB00",     ATA_HORKAGE_IVB, },
4463         { "TSSTcorp CDDVDW SH-S202J", "SB01",     ATA_HORKAGE_IVB, },
4464         { "TSSTcorp CDDVDW SH-S202N", "SB00",     ATA_HORKAGE_IVB, },
4465         { "TSSTcorp CDDVDW SH-S202N", "SB01",     ATA_HORKAGE_IVB, },
4466 
4467         /* End Marker */
4468         { }
4469 };
4470 
4471 static int strn_pattern_cmp(const char *patt, const char *name, int wildchar)
4472 {
4473         const char *p;
4474         int len;
4475 
4476         /*
4477          * check for trailing wildcard: *\0
4478          */
4479         p = strchr(patt, wildchar);
4480         if (p && ((*(p + 1)) == 0))
4481                 len = p - patt;
4482         else {
4483                 len = strlen(name);
4484                 if (!len) {
4485                         if (!*patt)
4486                                 return 0;
4487                         return -1;
4488                 }
4489         }
4490 
4491         return strncmp(patt, name, len);
4492 }
4493 
4494 static unsigned long ata_dev_blacklisted(const struct ata_device *dev)
4495 {
4496         unsigned char model_num[ATA_ID_PROD_LEN + 1];
4497         unsigned char model_rev[ATA_ID_FW_REV_LEN + 1];
4498         const struct ata_blacklist_entry *ad = ata_device_blacklist;
4499 
4500         ata_id_c_string(dev->id, model_num, ATA_ID_PROD, sizeof(model_num));
4501         ata_id_c_string(dev->id, model_rev, ATA_ID_FW_REV, sizeof(model_rev));
4502 
4503         while (ad->model_num) {
4504                 if (!strn_pattern_cmp(ad->model_num, model_num, '*')) {
4505                         if (ad->model_rev == NULL)
4506                                 return ad->horkage;
4507                         if (!strn_pattern_cmp(ad->model_rev, model_rev, '*'))
4508                                 return ad->horkage;
4509                 }
4510                 ad++;
4511         }
4512         return 0;
4513 }
4514 
4515 static int ata_dma_blacklisted(const struct ata_device *dev)
4516 {
4517         /* We don't support polling DMA.
4518          * DMA blacklist those ATAPI devices with CDB-intr (and use PIO)
4519          * if the LLDD handles only interrupts in the HSM_ST_LAST state.
4520          */
4521         if ((dev->link->ap->flags & ATA_FLAG_PIO_POLLING) &&
4522             (dev->flags & ATA_DFLAG_CDB_INTR))
4523                 return 1;
4524         return (dev->horkage & ATA_HORKAGE_NODMA) ? 1 : 0;
4525 }
4526 
4527 /**
4528  *      ata_is_40wire           -       check drive side detection
4529  *      @dev: device
4530  *
4531  *      Perform drive side detection decoding, allowing for device vendors
4532  *      who can't follow the documentation.
4533  */
4534 
4535 static int ata_is_40wire(struct ata_device *dev)
4536 {
4537         if (dev->horkage & ATA_HORKAGE_IVB)
4538                 return ata_drive_40wire_relaxed(dev->id);
4539         return ata_drive_40wire(dev->id);
4540 }
4541 
4542 /**
4543  *      ata_dev_xfermask - Compute supported xfermask of the given device
4544  *      @dev: Device to compute xfermask for
4545  *
4546  *      Compute supported xfermask of @dev and store it in
4547  *      dev->*_mask.  This function is responsible for applying all
4548  *      known limits including host controller limits, device
4549  *      blacklist, etc...
4550  *
4551  *      LOCKING:
4552  *      None.
4553  */
4554 static void ata_dev_xfermask(struct ata_device *dev)
4555 {
4556         struct ata_link *link = dev->link;
4557         struct ata_port *ap = link->ap;
4558         struct ata_host *host = ap->host;
4559         unsigned long xfer_mask;
4560 
4561         /* controller modes available */
4562         xfer_mask = ata_pack_xfermask(ap->pio_mask,
4563                                       ap->mwdma_mask, ap->udma_mask);
4564 
4565         /* drive modes available */
4566         xfer_mask &= ata_pack_xfermask(dev->pio_mask,
4567                                        dev->mwdma_mask, dev->udma_mask);
4568         xfer_mask &= ata_id_xfermask(dev->id);
4569 
4570         /*
4571          *      CFA Advanced TrueIDE timings are not allowed on a shared
4572          *      cable
4573          */
4574         if (ata_dev_pair(dev)) {
4575                 /* No PIO5 or PIO6 */
4576                 xfer_mask &= ~(0x03 << (ATA_SHIFT_PIO + 5));
4577                 /* No MWDMA3 or MWDMA 4 */
4578                 xfer_mask &= ~(0x03 << (ATA_SHIFT_MWDMA + 3));
4579         }
4580 
4581         if (ata_dma_blacklisted(dev)) {
4582                 xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4583                 ata_dev_printk(dev, KERN_WARNING,
4584                                "device is on DMA blacklist, disabling DMA\n");
4585         }
4586 
4587         if ((host->flags & ATA_HOST_SIMPLEX) &&
4588             host->simplex_claimed && host->simplex_claimed != ap) {
4589                 xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4590                 ata_dev_printk(dev, KERN_WARNING, "simplex DMA is claimed by "
4591                                "other device, disabling DMA\n");
4592         }
4593 
4594         if (ap->flags & ATA_FLAG_NO_IORDY)
4595                 xfer_mask &= ata_pio_mask_no_iordy(dev);
4596 
4597         if (ap->ops->mode_filter)
4598                 xfer_mask = ap->ops->mode_filter(dev, xfer_mask);
4599 
4600         /* Apply cable rule here.  Don't apply it early because when
4601          * we handle hot plug the cable type can itself change.
4602          * Check this last so that we know if the transfer rate was
4603          * solely limited by the cable.
4604          * Unknown or 80 wire cables reported host side are checked
4605          * drive side as well. Cases where we know a 40wire cable
4606          * is used safely for 80 are not checked here.
4607          */
4608         if (xfer_mask & (0xF8 << ATA_SHIFT_UDMA))
4609                 /* UDMA/44 or higher would be available */
4610                 if ((ap->cbl == ATA_CBL_PATA40) ||
4611                     (ata_is_40wire(dev) &&
4612                     (ap->cbl == ATA_CBL_PATA_UNK ||
4613                      ap->cbl == ATA_CBL_PATA80))) {
4614                         ata_dev_printk(dev, KERN_WARNING,
4615                                  "limited to UDMA/33 due to 40-wire cable\n");
4616                         xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
4617                 }
4618 
4619         ata_unpack_xfermask(xfer_mask, &dev->pio_mask,
4620                             &dev->mwdma_mask, &dev->udma_mask);
4621 }
4622 
4623 /**
4624  *      ata_dev_set_xfermode - Issue SET FEATURES - XFER MODE command
4625  *      @dev: Device to which command will be sent
4626  *
4627  *      Issue SET FEATURES - XFER MODE command to device @dev
4628  *      on port @ap.
4629  *
4630  *      LOCKING:
4631  *      PCI/etc. bus probe sem.
4632  *
4633  *      RETURNS:
4634  *      0 on success, AC_ERR_* mask otherwise.
4635  */
4636 
4637 static unsigned int ata_dev_set_xfermode(struct ata_device *dev)
4638 {
4639         struct ata_taskfile tf;
4640         unsigned int err_mask;
4641 
4642         /* set up set-features taskfile */
4643         DPRINTK("set features - xfer mode\n");
4644 
4645         /* Some controllers and ATAPI devices show flaky interrupt
4646          * behavior after setting xfer mode.  Use polling instead.
4647          */
4648         ata_tf_init(dev, &tf);
4649         tf.command = ATA_CMD_SET_FEATURES;
4650         tf.feature = SETFEATURES_XFER;
4651         tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_POLLING;
4652         tf.protocol = ATA_PROT_NODATA;
4653         /* If we are using IORDY we must send the mode setting command */
4654         if (ata_pio_need_iordy(dev))
4655                 tf.nsect = dev->xfer_mode;
4656         /* If the device has IORDY and the controller does not - turn it off */
4657         else if (ata_id_has_iordy(dev->id))
4658                 tf.nsect = 0x01;
4659         else /* In the ancient relic department - skip all of this */
4660                 return 0;
4661 
4662         err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4663 
4664         DPRINTK("EXIT, err_mask=%x\n", err_mask);
4665         return err_mask;
4666 }
4667 /**
4668  *      ata_dev_set_feature - Issue SET FEATURES - SATA FEATURES
4669  *      @dev: Device to which command will be sent
4670  *      @enable: Whether to enable or disable the feature
4671  *      @feature: The sector count represents the feature to set
4672  *
4673  *      Issue SET FEATURES - SATA FEATURES command to device @dev
4674  *      on port @ap with sector count
4675  *
4676  *      LOCKING:
4677  *      PCI/etc. bus probe sem.
4678  *
4679  *      RETURNS:
4680  *      0 on success, AC_ERR_* mask otherwise.
4681  */
4682 static unsigned int ata_dev_set_feature(struct ata_device *dev, u8 enable,
4683                                         u8 feature)
4684 {
4685         struct ata_taskfile tf;
4686         unsigned int err_mask;
4687 
4688         /* set up set-features taskfile */
4689         DPRINTK("set features - SATA features\n");
4690 
4691         ata_tf_init(dev, &tf);
4692         tf.command = ATA_CMD_SET_FEATURES;
4693         tf.feature = enable;
4694         tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4695         tf.protocol = ATA_PROT_NODATA;
4696         tf.nsect = feature;
4697 
4698         err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4699 
4700         DPRINTK("EXIT, err_mask=%x\n", err_mask);
4701         return err_mask;
4702 }
4703 
4704 /**
4705  *      ata_dev_init_params - Issue INIT DEV PARAMS command
4706  *      @dev: Device to which command will be sent
4707  *      @heads: Number of heads (taskfile parameter)
4708  *      @sectors: Number of sectors (taskfile parameter)
4709  *
4710  *      LOCKING:
4711  *      Kernel thread context (may sleep)
4712  *
4713  *      RETURNS:
4714  *      0 on success, AC_ERR_* mask otherwise.
4715  */
4716 static unsigned int ata_dev_init_params(struct ata_device *dev,
4717                                         u16 heads, u16 sectors)
4718 {
4719         struct ata_taskfile tf;
4720         unsigned int err_mask;
4721 
4722         /* Number of sectors per track 1-255. Number of heads 1-16 */
4723         if (sectors < 1 || sectors > 255 || heads < 1 || heads > 16)
4724                 return AC_ERR_INVALID;
4725 
4726         /* set up init dev params taskfile */
4727         DPRINTK("init dev params \n");
4728 
4729         ata_tf_init(dev, &tf);
4730         tf.command = ATA_CMD_INIT_DEV_PARAMS;
4731         tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4732         tf.protocol = ATA_PROT_NODATA;
4733         tf.nsect = sectors;
4734         tf.device |= (heads - 1) & 0x0f; /* max head = num. of heads - 1 */
4735 
4736         err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4737         /* A clean abort indicates an original or just out of spec drive
4738            and we should continue as we issue the setup based on the
4739            drive reported working geometry */
4740         if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
4741                 err_mask = 0;
4742 
4743         DPRINTK("EXIT, err_mask=%x\n", err_mask);
4744         return err_mask;
4745 }
4746 
4747 /**
4748  *      ata_sg_clean - Unmap DMA memory associated with command
4749  *      @qc: Command containing DMA memory to be released
4750  *
4751  *      Unmap all mapped DMA memory associated with this command.
4752  *
4753  *      LOCKING:
4754  *      spin_lock_irqsave(host lock)
4755  */
4756 void ata_sg_clean(struct ata_queued_cmd *qc)
4757 {
4758         struct ata_port *ap = qc->ap;
4759         struct scatterlist *sg = qc->sg;
4760         int dir = qc->dma_dir;
4761 
4762         WARN_ON(sg == NULL);
4763 
4764         VPRINTK("unmapping %u sg elements\n", qc->n_elem);
4765 
4766         if (qc->n_elem)
4767                 dma_unmap_sg(ap->dev, sg, qc->n_elem, dir);
4768 
4769         qc->flags &= ~ATA_QCFLAG_DMAMAP;
4770         qc->sg = NULL;
4771 }
4772 
4773 /**
4774  *      ata_fill_sg - Fill PCI IDE PRD table
4775  *      @qc: Metadata associated with taskfile to be transferred
4776  *
4777  *      Fill PCI IDE PRD (scatter-gather) table with segments
4778  *      associated with the current disk command.
4779  *
4780  *      LOCKING:
4781  *      spin_lock_irqsave(host lock)
4782  *
4783  */
4784 static void ata_fill_sg(struct ata_queued_cmd *qc)
4785 {
4786         struct ata_port *ap = qc->ap;
4787         struct scatterlist *sg;
4788         unsigned int si, pi;
4789 
4790         pi = 0;
4791         for_each_sg(qc->sg, sg, qc->n_elem, si) {
4792                 u32 addr, offset;
4793                 u32 sg_len, len;
4794 
4795                 /* determine if physical DMA addr spans 64K boundary.
4796                  * Note h/w doesn't support 64-bit, so we unconditionally
4797                  * truncate dma_addr_t to u32.
4798                  */
4799                 addr = (u32) sg_dma_address(sg);
4800                 sg_len = sg_dma_len(sg);
4801 
4802                 while (sg_len) {
4803                         offset = addr & 0xffff;
4804                         len = sg_len;
4805                         if ((offset + sg_len) > 0x10000)
4806                                 len = 0x10000 - offset;
4807 
4808                         ap->prd[pi].addr = cpu_to_le32(addr);
4809                         ap->prd[pi].flags_len = cpu_to_le32(len & 0xffff);
4810                         VPRINTK("PRD[%u] = (0x%X, 0x%X)\n", pi, addr, len);
4811 
4812                         pi++;
4813                         sg_len -= len;
4814                         addr += len;
4815                 }
4816         }
4817 
4818         ap->prd[pi - 1].flags_len |= cpu_to_le32(ATA_PRD_EOT);
4819 }
4820 
4821 /**
4822  *      ata_fill_sg_dumb - Fill PCI IDE PRD table
4823  *      @qc: Metadata associated with taskfile to be transferred
4824  *
4825  *      Fill PCI IDE PRD (scatter-gather) table with segments
4826  *      associated with the current disk command. Perform the fill
4827  *      so that we avoid writing any length 64K records for
4828  *      controllers that don't follow the spec.
4829  *
4830  *      LOCKING:
4831  *      spin_lock_irqsave(host lock)
4832  *
4833  */
4834 static void ata_fill_sg_dumb(struct ata_queued_cmd *qc)
4835 {
4836         struct ata_port *ap = qc->ap;
4837         struct scatterlist *sg;
4838         unsigned int si, pi;
4839 
4840         pi = 0;
4841         for_each_sg(qc->sg, sg, qc->n_elem, si) {
4842                 u32 addr, offset;
4843                 u32 sg_len, len, blen;
4844 
4845                 /* determine if physical DMA addr spans 64K boundary.
4846                  * Note h/w doesn't support 64-bit, so we unconditionally
4847                  * truncate dma_addr_t to u32.
4848                  */
4849                 addr = (u32) sg_dma_address(sg);
4850                 sg_len = sg_dma_len(sg);
4851 
4852                 while (sg_len) {
4853                         offset = addr & 0xffff;
4854                         len = sg_len;
4855                         if ((offset + sg_len) > 0x10000)
4856                                 len = 0x10000 - offset;
4857 
4858                         blen = len & 0xffff;
4859                         ap->prd[pi].addr = cpu_to_le32(addr);
4860                         if (blen == 0) {
4861                            /* Some PATA chipsets like the CS5530 can't
4862                               cope with 0x0000 meaning 64K as the spec says */
4863                                 ap->prd[pi].flags_len = cpu_to_le32(0x8000);
4864                                 blen = 0x8000;
4865                                 ap->prd[++pi].addr = cpu_to_le32(addr + 0x8000);
4866                         }
4867                         ap->prd[pi].flags_len = cpu_to_le32(blen);
4868                         VPRINTK("PRD[%u] = (0x%X, 0x%X)\n", pi, addr, len);
4869 
4870                         pi++;
4871                         sg_len -= len;
4872                         addr += len;
4873                 }
4874         }
4875 
4876         ap->prd[pi - 1].flags_len |= cpu_to_le32(ATA_PRD_EOT);
4877 }
4878 
4879 /**
4880  *      ata_check_atapi_dma - Check whether ATAPI DMA can be supported
4881  *      @qc: Metadata associated with taskfile to check
4882  *
4883  *      Allow low-level driver to filter ATA PACKET commands, returning
4884  *      a status indicating whether or not it is OK to use DMA for the
4885  *      supplied PACKET command.
4886  *
4887  *      LOCKING:
4888  *      spin_lock_irqsave(host lock)
4889  *
4890  *      RETURNS: 0 when ATAPI DMA can be used
4891  *               nonzero otherwise
4892  */
4893 int ata_check_atapi_dma(struct ata_queued_cmd *qc)
4894 {
4895         struct ata_port *ap = qc->ap;
4896 
4897         /* Don't allow DMA if it isn't multiple of 16 bytes.  Quite a
4898          * few ATAPI devices choke on such DMA requests.
4899          */
4900         if (unlikely(qc->nbytes & 15))
4901                 return 1;
4902 
4903         if (ap->ops->check_atapi_dma)
4904                 return ap->ops->check_atapi_dma(qc);
4905 
4906         return 0;
4907 }
4908 
4909 /**
4910  *      ata_std_qc_defer - Check whether a qc needs to be deferred
4911  *      @qc: ATA command in question
4912  *
4913  *      Non-NCQ commands cannot run with any other command, NCQ or
4914  *      not.  As upper layer only knows the queue depth, we are
4915  *      responsible for maintaining exclusion.  This function checks
4916  *      whether a new command @qc can be issued.
4917  *
4918  *      LOCKING:
4919  *      spin_lock_irqsave(host lock)
4920  *
4921  *      RETURNS:
4922  *      ATA_DEFER_* if deferring is needed, 0 otherwise.
4923  */
4924 int ata_std_qc_defer(struct ata_queued_cmd *qc)
4925 {
4926         struct ata_link *link = qc->dev->link;
4927 
4928         if (qc->tf.protocol == ATA_PROT_NCQ) {
4929                 if (!ata_tag_valid(link->active_tag))
4930                         return 0;
4931         } else {
4932                 if (!ata_tag_valid(link->active_tag) && !link->sactive)
4933                         return 0;
4934         }
4935 
4936         return ATA_DEFER_LINK;
4937 }
4938 
4939 /**
4940  *      ata_qc_prep - Prepare taskfile for submission
4941  *      @qc: Metadata associated with taskfile to be prepared
4942  *
4943  *      Prepare ATA taskfile for submission.
4944  *
4945  *      LOCKING:
4946  *      spin_lock_irqsave(host lock)
4947  */
4948 void ata_qc_prep(struct ata_queued_cmd *qc)
4949 {
4950         if (!(qc->flags & ATA_QCFLAG_DMAMAP))
4951                 return;
4952 
4953         ata_fill_sg(qc);
4954 }
4955 
4956 /**
4957  *      ata_dumb_qc_prep - Prepare taskfile for submission
4958  *      @qc: Metadata associated with taskfile to be prepared
4959  *
4960  *      Prepare ATA taskfile for submission.
4961  *
4962  *      LOCKING:
4963  *      spin_lock_irqsave(host lock)
4964  */
4965 void ata_dumb_qc_prep(struct ata_queued_cmd *qc)
4966 {
4967         if (!(qc->flags & ATA_QCFLAG_DMAMAP))
4968                 return;
4969 
4970         ata_fill_sg_dumb(qc);
4971 }
4972 
4973 void ata_noop_qc_prep(struct ata_queued_cmd *qc) { }
4974 
4975 /**
4976  *      ata_sg_init - Associate command with scatter-gather table.
4977  *      @qc: Command to be associated
4978  *      @sg: Scatter-gather table.
4979  *      @n_elem: Number of elements in s/g table.
4980  *
4981  *      Initialize the data-related elements of queued_cmd @qc
4982  *      to point to a scatter-gather table @sg, containing @n_elem
4983  *      elements.
4984  *
4985  *      LOCKING:
4986  *      spin_lock_irqsave(host lock)
4987  */
4988 void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
4989                  unsigned int n_elem)
4990 {
4991         qc->sg = sg;
4992         qc->n_elem = n_elem;
4993         qc->cursg = qc->sg;
4994 }
4995 
4996 /**
4997  *      ata_sg_setup - DMA-map the scatter-gather table associated with a command.
4998  *      @qc: Command with scatter-gather table to be mapped.
4999  *
5000  *      DMA-map the scatter-gather table associated with queued_cmd @qc.
5001  *
5002  *      LOCKING:
5003  *      spin_lock_irqsave(host lock)
5004  *
5005  *      RETURNS:
5006  *      Zero on success, negative on error.
5007  *
5008  */
5009 static int ata_sg_setup(struct ata_queued_cmd *qc)
5010 {
5011         struct ata_port *ap = qc->ap;
5012         unsigned int n_elem;
5013 
5014         VPRINTK("ENTER, ata%u\n", ap->print_id);
5015 
5016         n_elem = dma_map_sg(ap->dev, qc->sg, qc->n_elem, qc->dma_dir);
5017         if (n_elem < 1)
5018                 return -1;
5019 
5020         DPRINTK("%d sg elements mapped\n", n_elem);
5021 
5022         qc->n_elem = n_elem;
5023         qc->flags |= ATA_QCFLAG_DMAMAP;
5024 
5025         return 0;
5026 }
5027 
5028 /**
5029  *      swap_buf_le16 - swap halves of 16-bit words in place
5030  *      @buf:  Buffer to swap
5031  *      @buf_words:  Number of 16-bit words in buffer.
5032  *
5033  *      Swap halves of 16-bit words if needed to convert from
5034  *      little-endian byte order to native cpu byte order, or
5035  *      vice-versa.
5036  *
5037  *      LOCKING:
5038  *      Inherited from caller.
5039  */
5040 void swap_buf_le16(u16 *buf, unsigned int buf_words)
5041 {
5042 #ifdef __BIG_ENDIAN
5043         unsigned int i;
5044 
5045         for (i = 0; i < buf_words; i++)
5046                 buf[i] = le16_to_cpu(buf[i]);
5047 #endif /* __BIG_ENDIAN */
5048 }
5049 
5050 /**
5051  *      ata_data_xfer - Transfer data by PIO
5052  *      @dev: device to target
5053  *      @buf: data buffer
5054  *      @buflen: buffer length
5055  *      @rw: read/write
5056  *
5057  *      Transfer data from/to the device data register by PIO.
5058  *
5059  *      LOCKING:
5060  *      Inherited from caller.
5061  *
5062  *      RETURNS:
5063  *      Bytes consumed.
5064  */
5065 unsigned int ata_data_xfer(struct ata_device *dev, unsigned char *buf,
5066                            unsigned int buflen, int rw)
5067 {
5068         struct ata_port *ap = dev->link->ap;
5069         void __iomem *data_addr = ap->ioaddr.data_addr;
5070         unsigned int words = buflen >> 1;
5071 
5072         /* Transfer multiple of 2 bytes */
5073         if (rw == READ)
5074                 ioread16_rep(data_addr, buf, words);
5075         else
5076                 iowrite16_rep(data_addr, buf, words);
5077 
5078         /* Transfer trailing 1 byte, if any. */
5079         if (unlikely(buflen & 0x01)) {
5080                 __le16 align_buf[1] = { 0 };
5081                 unsigned char *trailing_buf = buf + buflen - 1;
5082 
5083                 if (rw == READ) {
5084                         align_buf[0] = cpu_to_le16(ioread16(data_addr));
5085                         memcpy(trailing_buf, align_buf, 1);
5086                 } else {
5087                         memcpy(align_buf, trailing_buf, 1);
5088                         iowrite16(le16_to_cpu(align_buf[0]), data_addr);
5089                 }
5090                 words++;
5091         }
5092 
5093         return words << 1;
5094 }
5095 
5096 /**
5097  *      ata_data_xfer_noirq - Transfer data by PIO
5098  *      @dev: device to target
5099  *      @buf: data buffer
5100  *      @buflen: buffer length
5101  *      @rw: read/write
5102  *
5103  *      Transfer data from/to the device data register by PIO. Do the
5104  *      transfer with interrupts disabled.
5105  *
5106  *      LOCKING:
5107  *      Inherited from caller.
5108  *
5109  *      RETURNS:
5110  *      Bytes consumed.
5111  */
5112 unsigned int ata_data_xfer_noirq(struct ata_device *dev, unsigned char *buf,
5113                                  unsigned int buflen, int rw)
5114 {
5115         unsigned long flags;
5116         unsigned int consumed;
5117 
5118         local_irq_save(flags);
5119         consumed = ata_data_xfer(dev, buf, buflen, rw);
5120         local_irq_restore(flags);
5121 
5122         return consumed;
5123 }
5124 
5125 
5126 /**
5127  *      ata_pio_sector - Transfer a sector of data.
5128  *      @qc: Command on going
5129  *
5130  *      Transfer qc->sect_size bytes of data from/to the ATA device.
5131  *
5132  *      LOCKING:
5133  *      Inherited from caller.
5134  */
5135 
5136 static void ata_pio_sector(struct ata_queued_cmd *qc)
5137 {
5138         int do_write = (qc->tf.flags & ATA_TFLAG_WRITE);
5139         struct ata_port *ap = qc->ap;
5140         struct page *page;
5141         unsigned int offset;
5142         unsigned char *buf;
5143 
5144         if (qc->curbytes == qc->nbytes - qc->sect_size)
5145                 ap->hsm_task_state = HSM_ST_LAST;
5146 
5147         page = sg_page(qc->cursg);
5148         offset = qc->cursg->offset + qc->cursg_ofs;
5149 
5150         /* get the current page and offset */
5151         page = nth_page(page, (offset >> PAGE_SHIFT));
5152         offset %= PAGE_SIZE;
5153 
5154         DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
5155 
5156         if (PageHighMem(page)) {
5157                 unsigned long flags;
5158 
5159                 /* FIXME: use a bounce buffer */
5160                 local_irq_save(flags);
5161                 buf = kmap_atomic(page, KM_IRQ0);
5162 
5163                 /* do the actual data transfer */
5164                 ap->ops->data_xfer(qc->dev, buf + offset, qc->sect_size, do_write);
5165 
5166                 kunmap_atomic(buf, KM_IRQ0);
5167                 local_irq_restore(flags);
5168         } else {
5169                 buf = page_address(page);
5170                 ap->ops->data_xfer(qc->dev, buf + offset, qc->sect_size, do_write);
5171         }
5172 
5173         qc->curbytes += qc->sect_size;
5174         qc->cursg_ofs += qc->sect_size;
5175 
5176         if (qc->cursg_ofs == qc->cursg->length) {
5177                 qc->cursg = sg_next(qc->cursg);
5178                 qc->cursg_ofs = 0;
5179         }
5180 }
5181 
5182 /**
5183  *      ata_pio_sectors - Transfer one or many sectors.
5184  *      @qc: Command on going
5185  *
5186  *      Transfer one or many sectors of data from/to the
5187  *      ATA device for the DRQ request.
5188  *
5189  *      LOCKING:
5190  *      Inherited from caller.
5191  */
5192 
5193 static void ata_pio_sectors(struct ata_queued_cmd *qc)
5194 {
5195         if (is_multi_taskfile(&qc->tf)) {
5196                 /* READ/WRITE MULTIPLE */
5197                 unsigned int nsect;
5198 
5199                 WARN_ON(qc->dev->multi_count == 0);
5200 
5201                 nsect = min((qc->nbytes - qc->curbytes) / qc->sect_size,
5202                             qc->dev->multi_count);
5203                 while (nsect--)
5204                         ata_pio_sector(qc);
5205         } else
5206                 ata_pio_sector(qc);
5207 
5208         ata_altstatus(qc->ap); /* flush */
5209 }
5210 
5211 /**
5212  *      atapi_send_cdb - Write CDB bytes to hardware
5213  *      @ap: Port to which ATAPI device is attached.
5214  *      @qc: Taskfile currently active
5215  *
5216  *      When device has indicated its readiness to accept
5217  *      a CDB, this function is called.  Send the CDB.
5218  *
5219  *      LOCKING:
5220  *      caller.
5221  */
5222 
5223 static void atapi_send_cdb(struct ata_port *ap, struct ata_queued_cmd *qc)
5224 {
5225         /* send SCSI cdb */
5226         DPRINTK("send cdb\n");
5227         WARN_ON(qc->dev->cdb_len < 12);
5228 
5229         ap->ops->data_xfer(qc->dev, qc->cdb, qc->dev->cdb_len, 1);
5230         ata_altstatus(ap); /* flush */
5231 
5232         switch (qc->tf.protocol) {
5233         case ATAPI_PROT_PIO:
5234                 ap->hsm_task_state = HSM_ST;
5235                 break;
5236         case ATAPI_PROT_NODATA:
5237                 ap->hsm_task_state = HSM_ST_LAST;
5238                 break;
5239         case ATAPI_PROT_DMA:
5240                 ap->hsm_task_state = HSM_ST_LAST;
5241                 /* initiate bmdma */
5242                 ap->ops->bmdma_start(qc);
5243                 break;
5244         }
5245 }
5246 
5247 /**
5248  *      __atapi_pio_bytes - Transfer data from/to the ATAPI device.
5249  *      @qc: Command on going
5250  *      @bytes: number of bytes
5251  *
5252  *      Transfer Transfer data from/to the ATAPI device.
5253  *
5254  *      LOCKING:
5255  *      Inherited from caller.
5256  *
5257  */
5258 static int __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
5259 {
5260         int rw = (qc->tf.flags & ATA_TFLAG_WRITE) ? WRITE : READ;
5261         struct ata_port *ap = qc->ap;
5262         struct ata_device *dev = qc->dev;
5263         struct ata_eh_info *ehi = &dev->link->eh_info;
5264         struct scatterlist *sg;
5265         struct page *page;
5266         unsigned char *buf;
5267         unsigned int offset, count, consumed;
5268 
5269 next_sg:
5270         sg = qc->cursg;
5271         if (unlikely(!sg)) {
5272                 ata_ehi_push_desc(ehi, "unexpected or too much trailing data "
5273                                   "buf=%u cur=%u bytes=%u",
5274                                   qc->nbytes, qc->curbytes, bytes);
5275                 return -1;
5276         }
5277 
5278         page = sg_page(sg);
5279         offset = sg->offset + qc->cursg_ofs;
5280 
5281         /* get the current page and offset */
5282         page = nth_page(page, (offset >> PAGE_SHIFT));
5283         offset %= PAGE_SIZE;
5284 
5285         /* don't overrun current sg */
5286         count = min(sg->length - qc->cursg_ofs, bytes);
5287 
5288         /* don't cross page boundaries */
5289         count = min(count, (unsigned int)PAGE_SIZE - offset);
5290 
5291         DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
5292 
5293         if (PageHighMem(page)) {
5294                 unsigned long flags;
5295 
5296                 /* FIXME: use bounce buffer */
5297                 local_irq_save(flags);
5298                 buf = kmap_atomic(page, KM_IRQ0);
5299 
5300                 /* do the actual data transfer */
5301                 consumed = ap->ops->data_xfer(dev,  buf + offset, count, rw);
5302 
5303                 kunmap_atomic(buf, KM_IRQ0);
5304                 local_irq_restore(flags);
5305         } else {
5306                 buf = page_address(page);
5307                 consumed = ap->ops->data_xfer(dev,  buf + offset, count, rw);
5308         }
5309 
5310         bytes -= min(bytes, consumed);
5311         qc->curbytes += count;
5312         qc->cursg_ofs += count;
5313 
5314         if (qc->cursg_ofs == sg->length) {
5315                 qc->cursg = sg_next(qc->cursg);
5316                 qc->cursg_ofs = 0;
5317         }
5318 
5319         /* consumed can be larger than count only for the last transfer */
5320         WARN_ON(qc->cursg && count != consumed);
5321 
5322         if (bytes)
5323                 goto next_sg;
5324         return 0;
5325 }
5326 
5327 /**
5328  *      atapi_pio_bytes - Transfer data from/to the ATAPI device.
5329  *      @qc: Command on going
5330  *
5331  *      Transfer Transfer data from/to the ATAPI device.
5332  *
5333  *      LOCKING:
5334  *      Inherited from caller.
5335  */
5336 
5337 static void atapi_pio_bytes(struct ata_queued_cmd *qc)
5338 {
5339         struct ata_port *ap = qc->ap;
5340         struct ata_device *dev = qc->dev;
5341         struct ata_eh_info *ehi = &dev->link->eh_info;
5342         unsigned int ireason, bc_lo, bc_hi, bytes;
5343         int i_write, do_write = (qc->tf.flags & ATA_TFLAG_WRITE) ? 1 : 0;
5344 
5345         /* Abuse qc->result_tf for temp storage of intermediate TF
5346          * here to save some kernel stack usage.
5347          * For normal completion, qc->result_tf is not relevant. For
5348          * error, qc->result_tf is later overwritten by ata_qc_complete().
5349          * So, the correctness of qc->result_tf is not affected.
5350          */
5351         ap->ops->tf_read(ap, &qc->result_tf);
5352         ireason = qc->result_tf.nsect;
5353         bc_lo = qc->result_tf.lbam;
5354         bc_hi = qc->result_tf.lbah;
5355         bytes = (bc_hi << 8) | bc_lo;
5356 
5357         /* shall be cleared to zero, indicating xfer of data */
5358         if (unlikely(ireason & (1 << 0)))
5359                 goto atapi_check;
5360 
5361         /* make sure transfer direction matches expected */
5362         i_write = ((ireason & (1 << 1)) == 0) ? 1 : 0;
5363         if (unlikely(do_write != i_write))
5364                 goto atapi_check;
5365 
5366         if (unlikely(!bytes))
5367                 goto atapi_check;
5368 
5369         VPRINTK("ata%u: xfering %d bytes\n", ap->print_id, bytes);
5370 
5371         if (unlikely(__atapi_pio_bytes(qc, bytes)))
5372                 goto err_out;
5373         ata_altstatus(ap); /* flush */
5374 
5375         return;
5376 
5377  atapi_check:
5378         ata_ehi_push_desc(ehi, "ATAPI check failed (ireason=0x%x bytes=%u)",
5379                           ireason, bytes);
5380  err_out:
5381         qc->err_mask |= AC_ERR_HSM;
5382         ap->hsm_task_state = HSM_ST_ERR;
5383 }
5384 
5385 /**
5386  *      ata_hsm_ok_in_wq - Check if the qc can be handled in the workqueue.
5387  *      @ap: the target ata_port
5388  *      @qc: qc on going
5389  *
5390  *      RETURNS:
5391  *      1 if ok in workqueue, 0 otherwise.
5392  */
5393 
5394 static inline int ata_hsm_ok_in_wq(struct ata_port *ap, struct ata_queued_cmd *qc)
5395 {
5396         if (qc->tf.flags & ATA_TFLAG_POLLING)
5397                 return 1;
5398 
5399         if (ap->hsm_task_state == HSM_ST_FIRST) {
5400                 if (qc->tf.protocol == ATA_PROT_PIO &&
5401                     (qc->tf.flags & ATA_TFLAG_WRITE))
5402                     return 1;
5403 
5404                 if (ata_is_atapi(qc->tf.protocol) &&
5405                     !(qc->dev->flags & ATA_DFLAG_CDB_INTR))
5406                         return 1;
5407         }
5408 
5409         return 0;
5410 }
5411 
5412 /**
5413  *      ata_hsm_qc_complete - finish a qc running on standard HSM
5414  *      @qc: Command to complete
5415  *      @in_wq: 1 if called from workqueue, 0 otherwise
5416  *
5417  *      Finish @qc which is running on standard HSM.
5418  *
5419  *      LOCKING:
5420  *      If @in_wq is zero, spin_lock_irqsave(host lock).
5421  *      Otherwise, none on entry and grabs host lock.
5422  */
5423 static void ata_hsm_qc_complete(struct ata_queued_cmd *qc, int in_wq)
5424 {
5425         struct ata_port *ap = qc->ap;
5426         unsigned long flags;
5427 
5428         if (ap->ops->error_handler) {
5429                 if (in_wq) {
5430                         spin_lock_irqsave(ap->lock, flags);
5431 
5432                         /* EH might have kicked in while host lock is
5433                          * released.
5434                          */
5435                         qc = ata_qc_from_tag(ap, qc->tag);
5436                         if (qc) {
5437                                 if (likely(!(qc->err_mask & AC_ERR_HSM))) {
5438                                         ap->ops->irq_on(ap);
5439                                         ata_qc_complete(qc);
5440                                 } else
5441                                         ata_port_freeze(ap);
5442                         }
5443 
5444                         spin_unlock_irqrestore(ap->lock, flags);
5445                 } else {
5446                         if (likely(!(qc->err_mask & AC_ERR_HSM)))
5447                                 ata_qc_complete(qc);
5448                         else
5449                                 ata_port_freeze(ap);
5450                 }
5451         } else {
5452                 if (in_wq) {
5453                         spin_lock_irqsave(ap->lock, flags);
5454                         ap->ops->irq_on(ap);
5455                         ata_qc_complete(qc);
5456                         spin_unlock_irqrestore(ap->lock, flags);
5457                 } else
5458                         ata_qc_complete(qc);
5459         }
5460 }
5461 
5462 /**
5463  *      ata_hsm_move - move the HSM to the next state.
5464  *      @ap: the target ata_port
5465  *      @qc: qc on going
5466  *      @status: current device status
5467  *      @in_wq: 1 if called from workqueue, 0 otherwise
5468  *
5469  *      RETURNS:
5470  *      1 when poll next status needed, 0 otherwise.
5471  */
5472 int ata_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc,
5473                  u8 status, int in_wq)
5474 {
5475         unsigned long flags = 0;
5476         int poll_next;
5477 
5478         WARN_ON((qc->flags & ATA_QCFLAG_ACTIVE) == 0);
5479 
5480         /* Make sure ata_qc_issue_prot() does not throw things
5481          * like DMA polling into the workqueue. Notice that
5482          * in_wq is not equivalent to (qc->tf.flags & ATA_TFLAG_POLLING).
5483          */
5484         WARN_ON(in_wq != ata_hsm_ok_in_wq(ap, qc));
5485 
5486 fsm_start:
5487         DPRINTK("ata%u: protocol %d task_state %d (dev_stat 0x%X)\n",
5488                 ap->print_id, qc->tf.protocol, ap->hsm_task_state, status);
5489 
5490         switch (ap->hsm_task_state) {
5491         case HSM_ST_FIRST:
5492                 /* Send first data block or PACKET CDB */
5493 
5494                 /* If polling, we will stay in the work queue after
5495                  * sending the data. Otherwise, interrupt handler
5496                  * takes over after sending the data.
5497                  */
5498                 poll_next = (qc->tf.flags & ATA_TFLAG_POLLING);
5499 
5500                 /* check device status */
5501                 if (unlikely((status & ATA_DRQ) == 0)) {
5502                         /* handle BSY=0, DRQ=0 as error */
5503                         if (likely(status & (ATA_ERR | ATA_DF)))
5504                                 /* device stops HSM for abort/error */
5505                                 qc->err_mask |= AC_ERR_DEV;
5506                         else
5507                                 /* HSM violation. Let EH handle this */
5508                                 qc->err_mask |= AC_ERR_HSM;
5509 
5510                         ap->hsm_task_state = HSM_ST_ERR;
5511                         goto fsm_start;
5512                 }
5513 
5514                 /* Device should not ask for data transfer (DRQ=1)
5515                  * when it finds something wrong.
5516                  * We ignore DRQ here and stop the HSM by
5517                  * changing hsm_task_state to HSM_ST_ERR and
5518                  * let the EH abort the command or reset the device.
5519                  */
5520                 if (unlikely(status & (ATA_ERR | ATA_DF))) {
5521                         /* Some ATAPI tape drives forget to clear the ERR bit
5522                          * when doing the next command (mostly request sense).
5523                          * We ignore ERR here to workaround and proceed sending
5524                          * the CDB.
5525                          */
5526                         if (!(qc->dev->horkage & ATA_HORKAGE_STUCK_ERR)) {
5527                                 ata_port_printk(ap, KERN_WARNING,
5528                                                 "DRQ=1 with device error, "
5529                                                 "dev_stat 0x%X\n", status);
5530                                 qc->err_mask |= AC_ERR_HSM;
5531                                 ap->hsm_task_state = HSM_ST_ERR;
5532                                 goto fsm_start;
5533                         }
5534                 }
5535 
5536                 /* Send the CDB (atapi) or the first data block (ata pio out).
5537                  * During the state transition, interrupt handler shouldn't
5538                  * be invoked before the data transfer is complete and
5539                  * hsm_task_state is changed. Hence, the following locking.
5540                  */
5541                 if (in_wq)
5542                         spin_lock_irqsave(ap->lock, flags);
5543 
5544                 if (qc->tf.protocol == ATA_PROT_PIO) {
5545                         /* PIO data out protocol.
5546                          * send first data block.
5547                          */
5548 
5549                         /* ata_pio_sectors() might change the state
5550                          * to HSM_ST_LAST. so, the state is changed here
5551                          * before ata_pio_sectors().
5552                          */
5553                         ap->hsm_task_state = HSM_ST;
5554                         ata_pio_sectors(qc);
5555                 } else
5556                         /* send CDB */
5557                         atapi_send_cdb(ap, qc);
5558 
5559                 if (in_wq)
5560                         spin_unlock_irqrestore(ap->lock, flags);
5561 
5562                 /* if polling, ata_pio_task() handles the rest.
5563                  * otherwise, interrupt handler takes over from here.
5564                  */
5565                 break;
5566 
5567         case HSM_ST:
5568                 /* complete command or read/write the data register */
5569                 if (qc->tf.protocol == ATAPI_PROT_PIO) {
5570                         /* ATAPI PIO protocol */
5571                         if ((status & ATA_DRQ) == 0) {
5572                                 /* No more data to transfer or device error.
5573                                  * Device error will be tagged in HSM_ST_LAST.
5574                                  */
5575                                 ap->hsm_task_state = HSM_ST_LAST;
5576                                 goto fsm_start;
5577                         }
5578 
5579                         /* Device should not ask for data transfer (DRQ=1)
5580                          * when it finds something wrong.
5581                          * We ignore DRQ here and stop the HSM by
5582                          * changing hsm_task_state to HSM_ST_ERR and
5583                          * let the EH abort the command or reset the device.
5584                          */
5585                         if (unlikely(status & (ATA_ERR | ATA_DF))) {
5586                                 ata_port_printk(ap, KERN_WARNING, "DRQ=1 with "
5587                                                 "device error, dev_stat 0x%X\n",
5588                                                 status);
5589                                 qc->err_mask |= AC_ERR_HSM;
5590                                 ap->hsm_task_state = HSM_ST_ERR;
5591                                 goto fsm_start;
5592                         }
5593 
5594                         atapi_pio_bytes(qc);
5595 
5596                         if (unlikely(ap->hsm_task_state == HSM_ST_ERR))
5597                                 /* bad ireason reported by device */
5598                                 goto fsm_start;
5599 
5600                 } else {
5601                         /* ATA PIO protocol */
5602                         if (unlikely((status & ATA_DRQ) == 0)) {
5603                                 /* handle BSY=0, DRQ=0 as error */
5604                                 if (likely(status & (ATA_ERR | ATA_DF)))
5605                                         /* device stops HSM for abort/error */
5606                                         qc->err_mask |= AC_ERR_DEV;
5607                                 else
5608                                         /* HSM violation. Let EH handle this.
5609                                          * Phantom devices also trigger this
5610                                          * condition.  Mark hint.
5611                                          */
5612                                         qc->err_mask |= AC_ERR_HSM |
5613                                                         AC_ERR_NODEV_HINT;
5614 
5615                                 ap->hsm_task_state = HSM_ST_ERR;
5616                                 goto fsm_start;
5617                         }
5618 
5619                         /* For PIO reads, some devices may ask for
5620                          * data transfer (DRQ=1) alone with ERR=1.
5621                          * We respect DRQ here and transfer one
5622                          * block of junk data before changing the
5623                          * hsm_task_state to HSM_ST_ERR.
5624                          *
5625                          * For PIO writes, ERR=1 DRQ=1 doesn't make
5626                          * sense since the data block has been
5627                          * transferred to the device.
5628                          */
5629                         if (unlikely(status & (ATA_ERR | ATA_DF))) {
5630                                 /* data might be corrputed */
5631                                 qc->err_mask |= AC_ERR_DEV;
5632 
5633                                 if (!(qc->tf.flags & ATA_TFLAG_WRITE)) {
5634                                         ata_pio_sectors(qc);
5635                                         status = ata_wait_idle(ap);
5636                                 }
5637 
5638                                 if (status & (ATA_BUSY | ATA_DRQ))
5639                                         qc->err_mask |= AC_ERR_HSM;
5640 
5641                                 /* ata_pio_sectors() might change the
5642                                  * state to HSM_ST_LAST. so, the state
5643                                  * is changed after ata_pio_sectors().
5644                                  */
5645                                 ap->hsm_task_state = HSM_ST_ERR;
5646                                 goto fsm_start;
5647                         }
5648 
5649                         ata_pio_sectors(qc);
5650 
5651                         if (ap->hsm_task_state == HSM_ST_LAST &&
5652                             (!(qc->tf.flags & ATA_TFLAG_WRITE))) {
5653                                 /* all data read */
5654                                 status = ata_wait_idle(ap);
5655                                 goto fsm_start;
5656                         }
5657                 }
5658 
5659                 poll_next = 1;
5660                 break;
5661 
5662         case HSM_ST_LAST:
5663                 if (unlikely(!ata_ok(status))) {
5664                         qc->err_mask |= __ac_err_mask(status);
5665                         ap->hsm_task_state = HSM_ST_ERR;
5666                         goto fsm_start;
5667                 }
5668 
5669                 /* no more data to transfer */
5670                 DPRINTK("ata%u: dev %u command complete, drv_stat 0x%x\n",
5671                         ap->print_id, qc->dev->devno, status);
5672 
5673                 WARN_ON(qc->err_mask);
5674 
5675                 ap->hsm_task_state = HSM_ST_IDLE;
5676 
5677                 /* complete taskfile transaction */
5678                 ata_hsm_qc_complete(qc, in_wq);
5679 
5680                 poll_next = 0;
5681                 break;
5682 
5683         case HSM_ST_ERR:
5684                 /* make sure qc->err_mask is available to
5685                  * know what's wrong and recover
5686                  */
5687                 WARN_ON(qc->err_mask == 0);
5688 
5689                 ap->hsm_task_state = HSM_ST_IDLE;
5690 
5691                 /* complete taskfile transaction */
5692                 ata_hsm_qc_complete(qc, in_wq);
5693 
5694                 poll_next = 0;
5695                 break;
5696         default:
5697                 poll_next = 0;
5698                 BUG();
5699         }
5700 
5701         return poll_next;
5702 }
5703 
5704 static void ata_pio_task(struct work_struct *work)
5705 {
5706         struct ata_port *ap =
5707                 container_of(work, struct ata_port, port_task.work);
5708         struct ata_queued_cmd *qc = ap->port_task_data;
5709         u8 status;
5710         int poll_next;
5711 
5712 fsm_start:
5713         WARN_ON(ap->hsm_task_state == HSM_ST_IDLE);
5714 
5715         /*
5716          * This is purely heuristic.  This is a fast path.
5717          * Sometimes when we enter, BSY will be cleared in
5718          * a chk-status or two.  If not, the drive is probably seeking
5719          * or something.  Snooze for a couple msecs, then
5720          * chk-status again.  If still busy, queue delayed work.
5721          */
5722         status = ata_busy_wait(ap, ATA_BUSY, 5);
5723         if (status & ATA_BUSY) {
5724                 msleep(2);
5725                 status = ata_busy_wait(ap, ATA_BUSY, 10);
5726                 if (status & ATA_BUSY) {
5727                         ata_pio_queue_task(ap, qc, ATA_SHORT_PAUSE);
5728                         return;
5729                 }
5730         }
5731 
5732         /* move the HSM */
5733         poll_next = ata_hsm_move(ap, qc, status, 1);
5734 
5735         /* another command or interrupt handler
5736          * may be running at this point.
5737          */
5738         if (poll_next)
5739                 goto fsm_start;
5740 }
5741 
5742 /**
5743  *      ata_qc_new - Request an available ATA command, for queueing
5744  *      @ap: Port associated with device @dev
5745  *      @dev: Device from whom we request an available command structure
5746  *
5747  *      LOCKING:
5748  *      None.
5749  */
5750 
5751 static struct ata_queued_cmd *ata_qc_new(struct ata_port *ap)
5752 {
5753         struct ata_queued_cmd *qc = NULL;
5754         unsigned int i;
5755 
5756         /* no command while frozen */
5757         if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))
5758                 return NULL;
5759 
5760         /* the last tag is reserved for internal command. */
5761         for (i = 0; i < ATA_MAX_QUEUE - 1; i++)
5762                 if (!test_and_set_bit(i, &ap->qc_allocated)) {
5763                         qc = __ata_qc_from_tag(ap, i);
5764                         break;
5765                 }
5766 
5767         if (qc)
5768                 qc->tag = i;
5769 
5770         return qc;
5771 }
5772 
5773 /**
5774  *      ata_qc_new_init - Request an available ATA command, and initialize it
5775  *      @dev: Device from whom we request an available command structure
5776  *
5777  *      LOCKING:
5778  *      None.
5779  */
5780 
5781 struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev)
5782 {
5783         struct ata_port *ap = dev->link->ap;
5784         struct ata_queued_cmd *qc;
5785 
5786         qc = ata_qc_new(ap);
5787         if (qc) {
5788                 qc->scsicmd = NULL;
5789                 qc->ap = ap;
5790                 qc->dev = dev;
5791 
5792                 ata_qc_reinit(qc);
5793         }
5794 
5795         return qc;
5796 }
5797 
5798 /**
5799  *      ata_qc_free - free unused ata_queued_cmd
5800  *      @qc: Command to complete
5801  *
5802  *      Designed to free unused ata_queued_cmd object
5803  *      in case something prevents using it.
5804  *
5805  *      LOCKING:
5806  *      spin_lock_irqsave(host lock)
5807  */
5808 void ata_qc_free(struct ata_queued_cmd *qc)
5809 {
5810         struct ata_port *ap = qc->ap;
5811         unsigned int tag;
5812 
5813         WARN_ON(qc == NULL);    /* ata_qc_from_tag _might_ return NULL */
5814 
5815         qc->flags = 0;
5816         tag = qc->tag;
5817         if (likely(ata_tag_valid(tag))) {
5818                 qc->tag = ATA_TAG_POISON;
5819                 clear_bit(tag, &ap->qc_allocated);
5820         }
5821 }
5822 
5823 void __ata_qc_complete(struct ata_queued_cmd *qc)
5824 {
5825         struct ata_port *ap = qc->ap;
5826         struct ata_link *link = qc->dev->link;
5827 
5828         WARN_ON(qc == NULL);    /* ata_qc_from_tag _might_ return NULL */
5829         WARN_ON(!(qc->flags & ATA_QCFLAG_ACTIVE));
5830 
5831         if (likely(qc->flags & ATA_QCFLAG_DMAMAP))
5832                 ata_sg_clean(qc);
5833 
5834         /* command should be marked inactive atomically with qc completion */
5835         if (qc->tf.protocol == ATA_PROT_NCQ) {
5836                 link->sactive &= ~(1 << qc->tag);
5837                 if (!link->sactive)
5838                         ap->nr_active_links--;
5839         } else {
5840                 link->active_tag = ATA_TAG_POISON;
5841                 ap->nr_active_links--;
5842         }
5843 
5844         /* clear exclusive status */
5845         if (unlikely(qc->flags & ATA_QCFLAG_CLEAR_EXCL &&
5846                      ap->excl_link == link))
5847                 ap->excl_link = NULL;
5848 
5849         /* atapi: mark qc as inactive to prevent the interrupt handler
5850          * from completing the command twice later, before the error handler
5851          * is called. (when rc != 0 and atapi request sense is needed)
5852          */
5853         qc->flags &= ~ATA_QCFLAG_ACTIVE;
5854         ap->qc_active &= ~(1 << qc->tag);
5855 
5856         /* call completion callback */
5857         qc->complete_fn(qc);
5858 }
5859 
5860 static void fill_result_tf(struct ata_queued_cmd *qc)
5861 {
5862         struct ata_port *ap = qc->ap;
5863 
5864         qc->result_tf.flags = qc->tf.flags;
5865         ap->ops->tf_read(ap, &qc->result_tf);
5866 }
5867 
5868 static void ata_verify_xfer(struct ata_queued_cmd *qc)
5869 {
5870         struct ata_device *dev = qc->dev;
5871 
5872         if (ata_tag_internal(qc->tag))
5873                 return;
5874 
5875         if (ata_is_nodata(qc->tf.protocol))
5876                 return;
5877 
5878         if ((dev->mwdma_mask || dev->udma_mask) && ata_is_pio(qc->tf.protocol))
5879                 return;
5880 
5881         dev->flags &= ~ATA_DFLAG_DUBIOUS_XFER;
5882 }
5883 
5884 /**
5885  *      ata_qc_complete - Complete an active ATA command
5886  *      @qc: Command to complete
5887  *      @err_mask: ATA Status register contents
5888  *
5889  *      Indicate to the mid and upper layers that an ATA
5890  *      command has completed, with either an ok or not-ok status.
5891  *
5892  *      LOCKING:
5893  *      spin_lock_irqsave(host lock)
5894  */
5895 void ata_qc_complete(struct ata_queued_cmd *qc)
5896 {
5897         struct ata_port *ap = qc->ap;
5898 
5899         /* XXX: New EH and old EH use different mechanisms to
5900          * synchronize EH with regular execution path.
5901          *
5902          * In new EH, a failed qc is marked with ATA_QCFLAG_FAILED.
5903          * Normal execution path is responsible for not accessing a
5904          * failed qc.  libata core enforces the rule by returning NULL
5905          * from ata_qc_from_tag() for failed qcs.
5906          *
5907          * Old EH depends on ata_qc_complete() nullifying completion
5908          * requests if ATA_QCFLAG_EH_SCHEDULED is set.  Old EH does
5909          * not synchronize with interrupt handler.  Only PIO task is
5910          * taken care of.
5911          */
5912         if (ap->ops->error_handler) {
5913                 struct ata_device *dev = qc->dev;
5914                 struct ata_eh_info *ehi = &dev->link->eh_info;
5915 
5916                 WARN_ON(ap->pflags & ATA_PFLAG_FROZEN);
5917 
5918                 if (unlikely(qc->err_mask))
5919                         qc->flags |= ATA_QCFLAG_FAILED;
5920 
5921                 if (unlikely(qc->flags & ATA_QCFLAG_FAILED)) {
5922                         if (!ata_tag_internal(qc->tag)) {
5923                                 /* always fill result TF for failed qc */
5924                                 fill_result_tf(qc);
5925                                 ata_qc_schedule_eh(qc);
5926                                 return;
5927                         }
5928                 }
5929 
5930                 /* read result TF if requested */
5931                 if (qc->flags & ATA_QCFLAG_RESULT_TF)
5932                         fill_result_tf(qc);
5933 
5934                 /* Some commands need post-processing after successful
5935                  * completion.
5936                  */
5937                 switch (qc->tf.command) {
5938                 case ATA_CMD_SET_FEATURES:
5939                         if (qc->tf.feature != SETFEATURES_WC_ON &&
5940                             qc->tf.feature != SETFEATURES_WC_OFF)
5941                                 break;
5942                         /* fall through */
5943                 case ATA_CMD_INIT_DEV_PARAMS: /* CHS translation changed */
5944                 case ATA_CMD_SET_MULTI: /* multi_count changed */
5945                         /* revalidate device */
5946                         ehi->dev_action[dev->devno] |= ATA_EH_REVALIDATE;
5947                         ata_port_schedule_eh(ap);
5948                         break;
5949 
5950                 case ATA_CMD_SLEEP:
5951                         dev->flags |= ATA_DFLAG_SLEEPING;
5952                         break;
5953                 }
5954 
5955                 if (unlikely(dev->flags & ATA_DFLAG_DUBIOUS_XFER))
5956                         ata_verify_xfer(qc);
5957 
5958                 __ata_qc_complete(qc);
5959         } else {
5960                 if (qc->flags & ATA_QCFLAG_EH_SCHEDULED)
5961                         return;
5962 
5963                 /* read result TF if failed or requested */
5964                 if (qc->err_mask || qc->flags & ATA_QCFLAG_RESULT_TF)
5965                         fill_result_tf(qc);
5966 
5967                 __ata_qc_complete(qc);
5968         }
5969 }
5970 
5971 /**
5972  *      ata_qc_complete_multiple - Complete multiple qcs successfully
5973  *      @ap: port in question
5974  *      @qc_active: new qc_active mask
5975  *      @finish_qc: LLDD callback invoked before completing a qc
5976  *
5977  *      Complete in-flight commands.  This functions is meant to be
5978  *      called from low-level driver's interrupt routine to complete
5979  *      requests normally.  ap->qc_active and @qc_active is compared
5980  *      and commands are completed accordingly.
5981  *
5982  *      LOCKING:
5983  *      spin_lock_irqsave(host lock)
5984  *
5985  *      RETURNS:
5986  *      Number of completed commands on success, -errno otherwise.
5987  */
5988 int ata_qc_complete_multiple(struct ata_port *ap, u32 qc_active,
5989                              void (*finish_qc)(struct ata_queued_cmd *))
5990 {
5991         int nr_done = 0;
5992         u32 done_mask;
5993         int i;
5994 
5995         done_mask = ap->qc_active ^ qc_active;
5996 
5997         if (unlikely(done_mask & qc_active)) {
5998                 ata_port_printk(ap, KERN_ERR, "illegal qc_active transition "
5999                                 "(%08x->%08x)\n", ap->qc_active, qc_active);
6000                 return -EINVAL;
6001         }
6002 
6003         for (i = 0; i < ATA_MAX_QUEUE; i++) {
6004                 struct ata_queued_cmd *qc;
6005 
6006                 if (!(done_mask & (1 << i)))
6007                         continue;
6008 
6009                 if ((qc = ata_qc_from_tag(ap, i))) {
6010                         if (finish_qc)
6011                                 finish_qc(qc);
6012                         ata_qc_complete(qc);
6013                         nr_done++;
6014                 }
6015         }
6016 
6017         return nr_done;
6018 }
6019 
6020 /**
6021  *      ata_qc_issue - issue taskfile to device
6022  *      @qc: command to issue to device
6023  *
6024  *      Prepare an ATA command to submission to device.
6025  *      This includes mapping the data into a DMA-able
6026  *      area, filling in the S/G table, and finally
6027  *      writing the taskfile to hardware, starting the command.
6028  *
6029  *      LOCKING:
6030  *      spin_lock_irqsave(host lock)
6031  */
6032 void ata_qc_issue(struct ata_queued_cmd *qc)
6033 {
6034         struct ata_port *ap = qc->ap;
6035         struct ata_link *link = qc->dev->link;
6036         u8 prot = qc->tf.protocol;
6037 
6038         /* Make sure only one non-NCQ command is outstanding.  The
6039          * check is skipped for old EH because it reuses active qc to
6040          * request ATAPI sense.
6041          */
6042         WARN_ON(ap->ops->error_handler && ata_tag_valid(link->active_tag));
6043 
6044         if (ata_is_ncq(prot)) {
6045                 WARN_ON(link->sactive & (1 << qc->tag));
6046 
6047                 if (!link->sactive)
6048                         ap->nr_active_links++;
6049                 link->sactive |= 1 << qc->tag;
6050         } else {
6051                 WARN_ON(link->sactive);
6052 
6053                 ap->nr_active_links++;
6054                 link->active_tag = qc->tag;
6055         }
6056 
6057         qc->flags |= ATA_QCFLAG_ACTIVE;
6058         ap->qc_active |= 1 << qc->tag;
6059 
6060         /* We guarantee to LLDs that they will have at least one
6061          * non-zero sg if the command is a data command.
6062          */
6063         BUG_ON(ata_is_data(prot) && (!qc->sg || !qc->n_elem || !qc->nbytes));
6064 
6065         if (ata_is_dma(prot) || (ata_is_pio(prot) &&
6066                                  (ap->flags & ATA_FLAG_PIO_DMA)))
6067                 if (ata_sg_setup(qc))
6068                         goto sg_err;
6069 
6070         /* if device is sleeping, schedule softreset and abort the link */
6071         if (unlikely(qc->dev->flags & ATA_DFLAG_SLEEPING)) {
6072                 link->eh_info.action |= ATA_EH_SOFTRESET;
6073                 ata_ehi_push_desc(&link->eh_info, "waking up from sleep");
6074                 ata_link_abort(link);
6075                 return;
6076         }
6077 
6078         ap->ops->qc_prep(qc);
6079 
6080         qc->err_mask |= ap->ops->qc_issue(qc);
6081         if (unlikely(qc->err_mask))
6082                 goto err;
6083         return;
6084 
6085 sg_err:
6086         qc->err_mask |= AC_ERR_SYSTEM;
6087 err:
6088         ata_qc_complete(qc);
6089 }
6090 
6091 /**
6092  *      ata_qc_issue_prot - issue taskfile to device in proto-dependent manner
6093  *      @qc: command to issue to device
6094  *
6095  *      Using various libata functions and hooks, this function
6096  *      starts an ATA command.  ATA commands are grouped into
6097  *      classes called "protocols", and issuing each type of protocol
6098  *      is slightly different.
6099  *
6100  *      May be used as the qc_issue() entry in ata_port_operations.
6101  *
6102  *      LOCKING:
6103  *      spin_lock_irqsave(host lock)
6104  *
6105  *      RETURNS:
6106  *      Zero on success, AC_ERR_* mask on failure
6107  */
6108 
6109 unsigned int ata_qc_issue_prot(struct ata_queued_cmd *qc)
6110 {
6111         struct ata_port *ap = qc->ap;
6112 
6113         /* Use polling pio if the LLD doesn't handle
6114          * interrupt driven pio and atapi CDB interrupt.
6115          */
6116         if (ap->flags & ATA_FLAG_PIO_POLLING) {
6117                 switch (qc->tf.protocol) {
6118                 case ATA_PROT_PIO:
6119                 case ATA_PROT_NODATA:
6120                 case ATAPI_PROT_PIO:
6121                 case ATAPI_PROT_NODATA:
6122                         qc->tf.flags |= ATA_TFLAG_POLLING;
6123                         break;
6124                 case ATAPI_PROT_DMA:
6125                         if (qc->dev->flags & ATA_DFLAG_CDB_INTR)
6126                                 /* see ata_dma_blacklisted() */
6127                                 BUG();
6128                         break;
6129                 default:
6130                         break;
6131                 }
6132         }
6133 
6134         /* select the device */
6135         ata_dev_select(ap, qc->dev->devno, 1, 0);
6136 
6137         /* start the command */
6138         switch (qc->tf.protocol) {
6139         case ATA_PROT_NODATA:
6140                 if (qc->tf.flags & ATA_TFLAG_POLLING)
6141                         ata_qc_set_polling(qc);
6142 
6143                 ata_tf_to_host(ap, &qc->tf);
6144                 ap->hsm_task_state = HSM_ST_LAST;
6145 
6146                 if (qc->tf.flags & ATA_TFLAG_POLLING)
6147                         ata_pio_queue_task(ap, qc, 0);
6148 
6149                 break;
6150 
6151         case ATA_PROT_DMA:
6152                 WARN_ON(qc->tf.flags & ATA_TFLAG_POLLING);
6153 
6154                 ap->ops->tf_load(ap, &qc->tf);   /* load tf registers */
6155                 ap->ops->bmdma_setup(qc);           /* set up bmdma */
6156                 ap->ops->bmdma_start(qc);           /* initiate bmdma */
6157                 ap->hsm_task_state = HSM_ST_LAST;
6158                 break;
6159 
6160         case ATA_PROT_PIO:
6161                 if (qc->tf.flags & ATA_TFLAG_POLLING)
6162                         ata_qc_set_polling(qc);
6163 
6164                 ata_tf_to_host(ap, &qc->tf);
6165 
6166                 if (qc->tf.flags & ATA_TFLAG_WRITE) {
6167                         /* PIO data out protocol */
6168                         ap->hsm_task_state = HSM_ST_FIRST;
6169                         ata_pio_queue_task(ap, qc, 0);
6170 
6171                         /* always send first data block using
6172                          * the ata_pio_task() codepath.
6173                          */
6174                 } else {
6175                         /* PIO data in protocol */
6176                         ap->hsm_task_state = HSM_ST;
6177 
6178                         if (qc->tf.flags & ATA_TFLAG_POLLING)
6179                                 ata_pio_queue_task(ap, qc, 0);
6180 
6181                         /* if polling, ata_pio_task() handles the rest.
6182                          * otherwise, interrupt handler takes over from here.
6183                          */
6184                 }
6185 
6186                 break;
6187 
6188         case ATAPI_PROT_PIO:
6189         case ATAPI_PROT_NODATA:
6190                 if (qc->tf.flags & ATA_TFLAG_POLLING)
6191                         ata_qc_set_polling(qc);
6192 
6193                 ata_tf_to_host(ap, &qc->tf);
6194 
6195                 ap->hsm_task_state = HSM_ST_FIRST;
6196 
6197                 /* send cdb by polling if no cdb interrupt */
6198                 if ((!(qc->dev->flags & ATA_DFLAG_CDB_INTR)) ||
6199                     (qc->tf.flags & ATA_TFLAG_POLLING))
6200                         ata_pio_queue_task(ap, qc, 0);
6201                 break;
6202 
6203         case ATAPI_PROT_DMA:
6204                 WARN_ON(qc->tf.flags & ATA_TFLAG_POLLING);
6205 
6206                 ap->ops->tf_load(ap, &qc->tf);   /* load tf registers */
6207                 ap->ops->bmdma_setup(qc);           /* set up bmdma */
6208                 ap->hsm_task_state = HSM_ST_FIRST;
6209 
6210                 /* send cdb by polling if no cdb interrupt */
6211                 if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
6212                         ata_pio_queue_task(ap, qc, 0);
6213                 break;
6214 
6215         default:
6216                 WARN_ON(1);
6217                 return AC_ERR_SYSTEM;
6218         }
6219 
6220         return 0;
6221 }
6222 
6223 /**
6224  *      ata_host_intr - Handle host interrupt for given (port, task)
6225  *      @ap: Port on which interrupt arrived (possibly...)
6226  *      @qc: Taskfile currently active in engine
6227  *
6228  *      Handle host interrupt for given queued command.  Currently,
6229  *      only DMA interrupts are handled.  All other commands are
6230  *      handled via polling with interrupts disabled (nIEN bit).
6231  *
6232  *      LOCKING:
6233  *      spin_lock_irqsave(host lock)
6234  *
6235  *      RETURNS:
6236  *      One if interrupt was handled, zero if not (shared irq).
6237  */
6238 
6239 inline unsigned int ata_host_intr(struct ata_port *ap,
6240                                   struct ata_queued_cmd *qc)
6241 {
6242         struct ata_eh_info *ehi = &ap->link.eh_info;
6243         u8 status, host_stat = 0;
6244 
6245         VPRINTK("ata%u: protocol %d task_state %d\n",
6246                 ap->print_id, qc->tf.protocol, ap->hsm_task_state);
6247 
6248         /* Check whether we are expecting interrupt in this state */
6249         switch (ap->hsm_task_state) {
6250         case HSM_ST_FIRST:
6251                 /* Some pre-ATAPI-4 devices assert INTRQ
6252                  * at this state when ready to receive CDB.
6253                  */
6254 
6255                 /* Check the ATA_DFLAG_CDB_INTR flag is enough here.
6256                  * The flag was turned on only for atapi devices.  No
6257                  * need to check ata_is_atapi(qc->tf.protocol) again.
6258                  */
6259                 if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
6260                         goto idle_irq;
6261                 break;
6262         case HSM_ST_LAST:
6263                 if (qc->tf.protocol == ATA_PROT_DMA ||
6264                     qc->tf.protocol == ATAPI_PROT_DMA) {
6265                         /* check status of DMA engine */
6266                         host_stat = ap->ops->bmdma_status(ap);
6267                         VPRINTK("ata%u: host_stat 0x%X\n",
6268                                 ap->print_id, host_stat);
6269 
6270                         /* if it's not our irq... */
6271                         if (!(host_stat & ATA_DMA_INTR))
6272                                 goto idle_irq;
6273 
6274                         /* before we do anything else, clear DMA-Start bit */
6275                         ap->ops->bmdma_stop(qc);
6276 
6277                         if (unlikely(host_stat & ATA_DMA_ERR)) {
6278                                 /* error when transfering data to/from memory */
6279                                 qc->err_mask |= AC_ERR_HOST_BUS;
6280                                 ap->hsm_task_state = HSM_ST_ERR;
6281                         }
6282                 }
6283                 break;
6284         case HSM_ST:
6285                 break;
6286         default:
6287                 goto idle_irq;
6288         }
6289 
6290         /* check altstatus */
6291         status = ata_altstatus(ap);
6292         if (status & ATA_BUSY)
6293                 goto idle_irq;
6294 
6295         /* check main status, clearing INTRQ */
6296         status = ata_chk_status(ap);
6297         if (unlikely(status & ATA_BUSY))
6298                 goto idle_irq;
6299 
6300         /* ack bmdma irq events */
6301         ap->ops->irq_clear(ap);
6302 
6303         ata_hsm_move(ap, qc, status, 0);
6304 
6305         if (unlikely(qc->err_mask) && (qc->tf.protocol == ATA_PROT_DMA ||
6306                                        qc->tf.protocol == ATAPI_PROT_DMA))
6307                 ata_ehi_push_desc(ehi, "BMDMA stat 0x%x", host_stat);
6308 
6309         return 1;       /* irq handled */
6310 
6311 idle_irq:
6312         ap->stats.idle_irq++;
6313 
6314 #ifdef ATA_IRQ_TRAP
6315         if ((ap->stats.idle_irq % 1000) == 0) {
6316                 ata_chk_status(ap);
6317                 ap->ops->irq_clear(ap);
6318                 ata_port_printk(ap, KERN_WARNING, "irq trap\n");
6319                 return 1;
6320         }
6321 #endif
6322         return 0;       /* irq not handled */
6323 }
6324 
6325 /**
6326  *      ata_interrupt - Default ATA host interrupt handler
6327  *      @irq: irq line (unused)
6328  *      @dev_instance: pointer to our ata_host information structure
6329  *
6330  *      Default interrupt handler for PCI IDE devices.  Calls
6331  *      ata_host_intr() for each port that is not disabled.
6332  *
6333  *      LOCKING:
6334  *      Obtains host lock during operation.
6335  *
6336  *      RETURNS:
6337  *      IRQ_NONE or IRQ_HANDLED.
6338  */
6339 
6340 irqreturn_t ata_interrupt(int irq, void *dev_instance)
6341 {
6342         struct ata_host *host = dev_instance;
6343         unsigned int i;
6344         unsigned int handled = 0;
6345         unsigned long flags;
6346 
6347         /* TODO: make _irqsave conditional on x86 PCI IDE legacy mode */
6348         spin_lock_irqsave(&host->lock, flags);
6349 
6350         for (i = 0; i < host->n_ports; i++) {
6351                 struct ata_port *ap;
6352 
6353                 ap = host->ports[i];
6354                 if (ap &&
6355                     !(ap->flags & ATA_FLAG_DISABLED)) {
6356                         struct ata_queued_cmd *qc;
6357 
6358                         qc = ata_qc_from_tag(ap, ap->link.active_tag);
6359                         if (qc && (!(qc->tf.flags & ATA_TFLAG_POLLING)) &&
6360                             (qc->flags & ATA_QCFLAG_ACTIVE))
6361                                 handled |= ata_host_intr(ap, qc);
6362                 }
6363         }
6364 
6365         spin_unlock_irqrestore(&host->lock, flags);
6366 
6367         return IRQ_RETVAL(handled);
6368 }
6369 
6370 /**
6371  *      sata_scr_valid - test whether SCRs are accessible
6372  *      @link: ATA link to test SCR accessibility for
6373  *
6374  *      Test whether SCRs are accessible for @link.
6375  *
6376  *      LOCKING:
6377  *      None.
6378  *
6379  *      RETURNS:
6380  *      1 if SCRs are accessible, 0 otherwise.
6381  */
6382 int sata_scr_valid(struct ata_link *link)
6383 {
6384         struct ata_port *ap = link->ap;
6385 
6386         return (ap->flags & ATA_FLAG_SATA) && ap->ops->scr_read;
6387 }
6388 
6389 /**
6390  *      sata_scr_read - read SCR register of the specified port
6391  *      @link: ATA link to read SCR for
6392  *      @reg: SCR to read
6393  *      @val: Place to store read value
6394  *
6395  *      Read SCR register @reg of @link into *@val.  This function is
6396  *      guaranteed to succeed if @link is ap->link, the cable type of
6397  *      the port is SATA and the port implements ->scr_read.
6398  *
6399  *      LOCKING:
6400  *      None if @link is ap->link.  Kernel thread context otherwise.
6401  *
6402  *      RETURNS:
6403  *      0 on success, negative errno on failure.
6404  */
6405 int sata_scr_read(struct ata_link *link, int reg, u32 *val)
6406 {
6407         if (ata_is_host_link(link)) {
6408                 struct ata_port *ap = link->ap;
6409 
6410                 if (sata_scr_valid(link))
6411                         return ap->ops->scr_read(ap, reg, val);
6412                 return -EOPNOTSUPP;
6413         }
6414 
6415         return sata_pmp_scr_read(link, reg, val);
6416 }
6417 
6418 /**
6419  *      sata_scr_write - write SCR register of the specified port
6420  *      @link: ATA link to write SCR for
6421  *      @reg: SCR to write
6422  *      @val: value to write
6423  *
6424  *      Write @val to SCR register @reg of @link.  This function is
6425  *      guaranteed to succeed if @link is ap->link, the cable type of
6426  *      the port is SATA and the port implements ->scr_read.
6427  *
6428  *      LOCKING:
6429  *      None if @link is ap->link.  Kernel thread context otherwise.
6430  *
6431  *      RETURNS:
6432  *      0 on success, negative errno on failure.
6433  */
6434 int sata_scr_write(struct ata_link *link, int reg, u32 val)
6435 {
6436         if (ata_is_host_link(link)) {
6437                 struct ata_port *ap = link->ap;
6438 
6439                 if (sata_scr_valid(link))
6440                         return ap->ops->scr_write(ap, reg, val);
6441                 return -EOPNOTSUPP;
6442         }
6443 
6444         return sata_pmp_scr_write(link, reg, val);
6445 }
6446 
6447 /**
6448  *      sata_scr_write_flush - write SCR register of the specified port and flush
6449  *      @link: ATA link to write SCR for
6450  *      @reg: SCR to write
6451  *      @val: value to write
6452  *
6453  *      This function is identical to sata_scr_write() except that this
6454  *      function performs flush after writing to the register.
6455  *
6456  *      LOCKING:
6457  *      None if @link is ap->link.  Kernel thread context otherwise.
6458  *
6459  *      RETURNS:
6460  *      0 on success, negative errno on failure.
6461  */
6462 int sata_scr_write_flush(struct ata_link *link, int reg, u32 val)
6463 {
6464         if (ata_is_host_link(link)) {
6465                 struct ata_port *ap = link->ap;
6466                 int rc;
6467 
6468                 if (sata_scr_valid(link)) {
6469                         rc = ap->ops->scr_write(ap, reg, val);
6470                         if (rc == 0)
6471                                 rc = ap->ops->scr_read(ap, reg, &val);
6472                         return rc;
6473                 }
6474                 return -EOPNOTSUPP;
6475         }
6476 
6477         return sata_pmp_scr_write(link, reg, val);
6478 }
6479 
6480 /**
6481  *      ata_link_online - test whether the given link is online
6482  *      @link: ATA link to test
6483  *
6484  *      Test whether @link is online.  Note that this function returns
6485  *      0 if online status of @link cannot be obtained, so
6486  *      ata_link_online(link) != !ata_link_offline(link).
6487  *
6488  *      LOCKING:
6489  *      None.
6490  *
6491  *      RETURNS:
6492  *      1 if the port online status is available and online.
6493  */
6494 int ata_link_online(struct ata_link *link)
6495 {
6496         u32 sstatus;
6497 
6498         if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
6499             (sstatus & 0xf) == 0x3)
6500                 return 1;
6501         return 0;
6502 }
6503 
6504 /**
6505  *      ata_link_offline - test whether the given link is offline
6506  *      @link: ATA link to test
6507  *
6508  *      Test whether @link is offline.  Note that this function
6509  *      returns 0 if offline status of @link cannot be obtained, so
6510  *      ata_link_online(link) != !ata_link_offline(link).
6511  *
6512  *      LOCKING:
6513  *      None.
6514  *
6515  *      RETURNS:
6516  *      1 if the port offline status is available and offline.
6517  */
6518 int ata_link_offline(struct ata_link *link)
6519 {
6520         u32 sstatus;
6521 
6522         if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
6523             (sstatus & 0xf) != 0x3)
6524                 return 1;
6525         return 0;
6526 }
6527 
6528 int ata_flush_cache(struct ata_device *dev)
6529 {
6530         unsigned int err_mask;
6531         u8 cmd;
6532 
6533         if (!ata_try_flush_cache(dev))
6534                 return 0;
6535 
6536         if (dev->flags & ATA_DFLAG_FLUSH_EXT)
6537                 cmd = ATA_CMD_FLUSH_EXT;
6538         else
6539                 cmd = ATA_CMD_FLUSH;
6540 
6541         /* This is wrong. On a failed flush we get back the LBA of the lost
6542            sector and we should (assuming it wasn't aborted as unknown) issue
6543            a further flush command to continue the writeback until it
6544            does not error */
6545         err_mask = ata_do_simple_cmd(dev, cmd);
6546         if (err_mask) {
6547                 ata_dev_printk(dev, KERN_ERR, "failed to flush cache\n");
6548                 return -EIO;
6549         }
6550 
6551         return 0;
6552 }
6553 
6554 #ifdef CONFIG_PM
6555 static int ata_host_request_pm(struct ata_host *host, pm_message_t mesg,
6556                                unsigned int action, unsigned int ehi_flags,
6557                                int wait)
6558 {
6559         unsigned long flags;
6560         int i, rc;
6561 
6562         for (i = 0; i < host->n_ports; i++) {
6563                 struct ata_port *ap = host->ports[i];
6564                 struct ata_link *link;
6565 
6566                 /* Previous resume operation might still be in
6567                  * progress.  Wait for PM_PENDING to clear.
6568                  */
6569                 if (ap->pflags & ATA_PFLAG_PM_PENDING) {
6570                         ata_port_wait_eh(ap);
6571                         WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
6572                 }
6573 
6574                 /* request PM ops to EH */
6575                 spin_lock_irqsave(ap->lock, flags);
6576 
6577                 ap->pm_mesg = mesg;
6578                 if (wait) {
6579                         rc = 0;
6580                         ap->pm_result = &rc;
6581                 }
6582 
6583                 ap->pflags |= ATA_PFLAG_PM_PENDING;
6584                 __ata_port_for_each_link(link, ap) {
6585                         link->eh_info.action |= action;
6586                         link->eh_info.flags |= ehi_flags;
6587                 }
6588 
6589                 ata_port_schedule_eh(ap);
6590 
6591                 spin_unlock_irqrestore(ap->lock, flags);
6592 
6593                 /* wait and check result */
6594                 if (wait) {
6595                         ata_port_wait_eh(ap);
6596                         WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
6597                         if (rc)
6598                                 return rc;
6599                 }
6600         }
6601 
6602         return 0;
6603 }
6604 
6605 /**
6606  *      ata_host_suspend - suspend host
6607  *      @host: host to suspend
6608  *      @mesg: PM message
6609  *
6610  *      Suspend @host.  Actual operation is performed by EH.  This
6611  *      function requests EH to perform PM operations and waits for EH
6612  *      to finish.
6613  *
6614  *      LOCKING:
6615  *      Kernel thread context (may sleep).
6616  *
6617  *      RETURNS:
6618  *      0 on success, -errno on failure.
6619  */
6620 int ata_host_suspend(struct ata_host *host, pm_message_t mesg)
6621 {
6622         int rc;
6623 
6624         /*
6625          * disable link pm on all ports before requesting
6626          * any pm activity
6627          */
6628         ata_lpm_enable(host);
6629 
6630         rc = ata_host_request_pm(host, mesg, 0, ATA_EHI_QUIET, 1);
6631         if (rc == 0)
6632                 host->dev->power.power_state = mesg;
6633         return rc;
6634 }
6635 
6636 /**
6637  *      ata_host_resume - resume host
6638  *      @host: host to resume
6639  *
6640  *      Resume @host.  Actual operation is performed by EH.  This
6641  *      function requests EH to perform PM operations and returns.
6642  *      Note that all resume operations are performed parallely.
6643  *
6644  *      LOCKING:
6645  *      Kernel thread context (may sleep).
6646  */
6647 void ata_host_resume(struct ata_host *host)
6648 {
6649         ata_host_request_pm(host, PMSG_ON, ATA_EH_SOFTRESET,
6650                             ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 0);
6651         host->dev->power.power_state = PMSG_ON;
6652 
6653         /* reenable link pm */
6654         ata_lpm_disable(host);
6655 }
6656 #endif
6657 
6658 /**
6659  *      ata_port_start - Set port up for dma.
6660  *      @ap: Port to initialize
6661  *
6662  *      Called just after data structures for each port are
6663  *      initialized.  Allocates space for PRD table.
6664  *
6665  *      May be used as the port_start() entry in ata_port_operations.
6666  *
6667  *      LOCKING:
6668  *      Inherited from caller.
6669  */
6670 int ata_port_start(struct ata_port *ap)
6671 {
6672         struct device *dev = ap->dev;
6673 
6674         ap->prd = dmam_alloc_coherent(dev, ATA_PRD_TBL_SZ, &ap->prd_dma,
6675                                       GFP_KERNEL);
6676         if (!ap->prd)
6677                 return -ENOMEM;
6678 
6679         return 0;
6680 }
6681 
6682 /**
6683  *      ata_dev_init - Initialize an ata_device structure
6684  *      @dev: Device structure to initialize
6685  *
6686  *      Initialize @dev in preparation for probing.
6687  *
6688  *      LOCKING:
6689  *      Inherited from caller.
6690  */
6691 void ata_dev_init(struct ata_device *dev)
6692 {
6693         struct ata_link *link = dev->link;
6694         struct ata_port *ap = link->ap;
6695         unsigned long flags;
6696 
6697         /* SATA spd limit is bound to the first device */
6698         link->sata_spd_limit = link->hw_sata_spd_limit;
6699         link->sata_spd = 0;
6700 
6701         /* High bits of dev->flags are used to record warm plug
6702          * requests which occur asynchronously.  Synchronize using
6703          * host lock.
6704          */
6705         spin_lock_irqsave(ap->lock, flags);
6706         dev->flags &= ~ATA_DFLAG_INIT_MASK;
6707         dev->horkage = 0;
6708         spin_unlock_irqrestore(ap->lock, flags);
6709 
6710         memset((void *)dev + ATA_DEVICE_CLEAR_OFFSET, 0,
6711                sizeof(*dev) - ATA_DEVICE_CLEAR_OFFSET);
6712         dev->pio_mask = UINT_MAX;
6713         dev->mwdma_mask = UINT_MAX;
6714         dev->udma_mask = UINT_MAX;
6715 }
6716 
6717 /**
6718  *      ata_link_init - Initialize an ata_link structure
6719  *      @ap: ATA port link is attached to
6720  *      @link: Link structure to initialize
6721  *      @pmp: Port multiplier port number
6722  *
6723  *      Initialize @link.
6724  *
6725  *      LOCKING:
6726  *      Kernel thread context (may sleep)
6727  */
6728 void ata_link_init(struct ata_port *ap, struct ata_link *link, int pmp)
6729 {
6730         int i;
6731 
6732         /* clear everything except for devices */
6733         memset(link, 0, offsetof(struct ata_link, device[0]));
6734 
6735         link->ap = ap;
6736         link->pmp = pmp;
6737         link->active_tag = ATA_TAG_POISON;
6738         link->hw_sata_spd_limit = UINT_MAX;
6739 
6740         /* can't use iterator, ap isn't initialized yet */
6741         for (i = 0; i < ATA_MAX_DEVICES; i++) {
6742                 struct ata_device *dev = &link->device[i];
6743 
6744                 dev->link = link;
6745                 dev->devno = dev - link->device;
6746                 ata_dev_init(dev);
6747         }
6748 }
6749 
6750 /**
6751  *      sata_link_init_spd - Initialize link->sata_spd_limit
6752  *      @link: Link to configure sata_spd_limit for
6753  *
6754  *      Initialize @link->[hw_]sata_spd_limit to the currently
6755  *      configured value.
6756  *
6757  *      LOCKING:
6758  *      Kernel thread context (may sleep).
6759  *
6760  *      RETURNS:
6761  *      0 on success, -errno on failure.
6762  */
6763 int sata_link_init_spd(struct ata_link *link)
6764 {
6765         u32 scontrol;
6766         u8 spd;
6767         int rc;
6768 
6769         rc = sata_scr_read(link, SCR_CONTROL, &scontrol);
6770         if (rc)
6771                 return rc;
6772 
6773         spd = (scontrol >> 4) & 0xf;
6774         if (spd)
6775                 link->hw_sata_spd_limit &= (1 << spd) - 1;
6776 
6777         ata_force_spd_limit(link);
6778 
6779         link->sata_spd_limit = link->hw_sata_spd_limit;
6780 
6781         return 0;
6782 }
6783 
6784 /**
6785  *      ata_port_alloc - allocate and initialize basic ATA port resources
6786  *      @host: ATA host this allocated port belongs to
6787  *
6788  *      Allocate and initialize basic ATA port resources.
6789  *
6790  *      RETURNS:
6791  *      Allocate ATA port on success, NULL on failure.
6792  *
6793  *      LOCKING:
6794  *      Inherited from calling layer (may sleep).
6795  */
6796 struct ata_port *ata_port_alloc(struct ata_host *host)
6797 {
6798         struct ata_port *ap;
6799 
6800         DPRINTK("ENTER\n");
6801 
6802         ap = kzalloc(sizeof(*ap), GFP_KERNEL);
6803         if (!ap)
6804                 return NULL;
6805 
6806         ap->pflags |= ATA_PFLAG_INITIALIZING;
6807         ap->lock = &host->lock;
6808         ap->flags = ATA_FLAG_DISABLED;
6809         ap->print_id = -1;
6810         ap->ctl = ATA_DEVCTL_OBS;
6811         ap->host = host;
6812         ap->dev = host->dev;
6813         ap->last_ctl = 0xFF;
6814 
6815 #if defined(ATA_VERBOSE_DEBUG)
6816         /* turn on all debugging levels */
6817         ap->msg_enable = 0x00FF;
6818 #elif defined(ATA_DEBUG)
6819         ap->msg_enable = ATA_MSG_DRV | ATA_MSG_INFO | ATA_MSG_CTL | ATA_MSG_WARN | ATA_MSG_ERR;
6820 #else
6821         ap->msg_enable = ATA_MSG_DRV | ATA_MSG_ERR | ATA_MSG_WARN;
6822 #endif
6823 
6824         INIT_DELAYED_WORK(&ap->port_task, ata_pio_task);
6825         INIT_DELAYED_WORK(&ap->hotplug_task, ata_scsi_hotplug);
6826         INIT_WORK(&ap->scsi_rescan_task, ata_scsi_dev_rescan);
6827         INIT_LIST_HEAD(&ap->eh_done_q);
6828         init_waitqueue_head(&ap->eh_wait_q);
6829         init_timer_deferrable(&ap->fastdrain_timer);
6830         ap->fastdrain_timer.function = ata_eh_fastdrain_timerfn;
6831         ap->fastdrain_timer.data = (unsigned long)ap;
6832 
6833         ap->cbl = ATA_CBL_NONE;
6834 
6835         ata_link_init(ap, &ap->link, 0);
6836 
6837 #ifdef ATA_IRQ_TRAP
6838         ap->stats.unhandled_irq = 1;
6839         ap->stats.idle_irq = 1;
6840 #endif
6841         return ap;
6842 }
6843 
6844 static void ata_host_release(struct device *gendev, void *res)
6845 {
6846         struct ata_host *host = dev_get_drvdata(gendev);
6847         int i;
6848 
6849         for (i = 0; i < host->n_ports; i++) {
6850                 struct ata_port *ap = host->ports[i];
6851 
6852                 if (!ap)
6853                         continue;
6854 
6855                 if (ap->scsi_host)
6856                         scsi_host_put(ap->scsi_host);
6857 
6858                 kfree(ap->pmp_link);
6859                 kfree(ap);
6860                 host->ports[i] = NULL;
6861         }
6862 
6863         dev_set_drvdata(gendev, NULL);
6864 }
6865 
6866 /**
6867  *      ata_host_alloc - allocate and init basic ATA host resources
6868  *      @dev: generic device this host is associated with
6869  *      @max_ports: maximum number of ATA ports associated with this host
6870  *
6871  *      Allocate and initialize basic ATA host resources.  LLD calls
6872  *      this function to allocate a host, initializes it fully and
6873  *      attaches it using ata_host_register().
6874  *
6875  *      @max_ports ports are allocated and host->n_ports is
6876  *      initialized to @max_ports.  The caller is allowed to decrease
6877  *      host->n_ports before calling ata_host_register().  The unused
6878  *      ports will be automatically freed on registration.
6879  *
6880  *      RETURNS:
6881  *      Allocate ATA host on success, NULL on failure.
6882  *
6883  *      LOCKING:
6884  *      Inherited from calling layer (may sleep).
6885  */
6886 struct ata_host *ata_host_alloc(struct device *dev, int max_ports)
6887 {
6888         struct ata_host *host;
6889         size_t sz;
6890         int i;
6891 
6892         DPRINTK("ENTER\n");
6893 
6894         if (!devres_open_group(dev, NULL, GFP_KERNEL))
6895                 return NULL;
6896 
6897         /* alloc a container for our list of ATA ports (buses) */
6898         sz = sizeof(struct ata_host) + (max_ports + 1) * sizeof(void *);
6899         /* alloc a container for our list of ATA ports (buses) */
6900         host = devres_alloc(ata_host_release, sz, GFP_KERNEL);
6901         if (!host)
6902                 goto err_out;
6903 
6904         devres_add(dev, host);
6905         dev_set_drvdata(dev, host);
6906