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 /* linux/drivers/mtd/nand/s3c2410.c
  2  *
  3  * Copyright (c) 2004,2005 Simtec Electronics
  4  *      http://www.simtec.co.uk/products/SWLINUX/
  5  *      Ben Dooks <ben@simtec.co.uk>
  6  *
  7  * Samsung S3C2410/S3C240 NAND driver
  8  *
  9  * Changelog:
 10  *      21-Sep-2004  BJD  Initial version
 11  *      23-Sep-2004  BJD  Multiple device support
 12  *      28-Sep-2004  BJD  Fixed ECC placement for Hardware mode
 13  *      12-Oct-2004  BJD  Fixed errors in use of platform data
 14  *      18-Feb-2005  BJD  Fix sparse errors
 15  *      14-Mar-2005  BJD  Applied tglx's code reduction patch
 16  *      02-May-2005  BJD  Fixed s3c2440 support
 17  *      02-May-2005  BJD  Reduced hwcontrol decode
 18  *      20-Jun-2005  BJD  Updated s3c2440 support, fixed timing bug
 19  *      08-Jul-2005  BJD  Fix OOPS when no platform data supplied
 20  *      20-Oct-2005  BJD  Fix timing calculation bug
 21  *      14-Jan-2006  BJD  Allow clock to be stopped when idle
 22  *
 23  * $Id: s3c2410.c,v 1.23 2006/04/01 18:06:29 bjd Exp $
 24  *
 25  * This program is free software; you can redistribute it and/or modify
 26  * it under the terms of the GNU General Public License as published by
 27  * the Free Software Foundation; either version 2 of the License, or
 28  * (at your option) any later version.
 29  *
 30  * This program is distributed in the hope that it will be useful,
 31  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 32  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 33  * GNU General Public License for more details.
 34  *
 35  * You should have received a copy of the GNU General Public License
 36  * along with this program; if not, write to the Free Software
 37  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 38 */
 39 
 40 #ifdef CONFIG_MTD_NAND_S3C2410_DEBUG
 41 #define DEBUG
 42 #endif
 43 
 44 #include <linux/module.h>
 45 #include <linux/types.h>
 46 #include <linux/init.h>
 47 #include <linux/kernel.h>
 48 #include <linux/string.h>
 49 #include <linux/ioport.h>
 50 #include <linux/platform_device.h>
 51 #include <linux/delay.h>
 52 #include <linux/err.h>
 53 #include <linux/slab.h>
 54 #include <linux/clk.h>
 55 
 56 #include <linux/mtd/mtd.h>
 57 #include <linux/mtd/nand.h>
 58 #include <linux/mtd/nand_ecc.h>
 59 #include <linux/mtd/partitions.h>
 60 
 61 #include <asm/io.h>
 62 
 63 #include <asm/plat-s3c/regs-nand.h>
 64 #include <asm/plat-s3c/nand.h>
 65 
 66 #ifdef CONFIG_MTD_NAND_S3C2410_HWECC
 67 static int hardware_ecc = 1;
 68 #else
 69 static int hardware_ecc = 0;
 70 #endif
 71 
 72 #ifdef CONFIG_MTD_NAND_S3C2410_CLKSTOP
 73 static int clock_stop = 1;
 74 #else
 75 static const int clock_stop = 0;
 76 #endif
 77 
 78 
 79 /* new oob placement block for use with hardware ecc generation
 80  */
 81 
 82 static struct nand_ecclayout nand_hw_eccoob = {
 83         .eccbytes = 3,
 84         .eccpos = {0, 1, 2},
 85         .oobfree = {{8, 8}}
 86 };
 87 
 88 /* controller and mtd information */
 89 
 90 struct s3c2410_nand_info;
 91 
 92 struct s3c2410_nand_mtd {
 93         struct mtd_info                 mtd;
 94         struct nand_chip                chip;
 95         struct s3c2410_nand_set         *set;
 96         struct s3c2410_nand_info        *info;
 97         int                             scan_res;
 98 };
 99 
100 enum s3c_cpu_type {
101         TYPE_S3C2410,
102         TYPE_S3C2412,
103         TYPE_S3C2440,
104 };
105 
106 /* overview of the s3c2410 nand state */
107 
108 struct s3c2410_nand_info {
109         /* mtd info */
110         struct nand_hw_control          controller;
111         struct s3c2410_nand_mtd         *mtds;
112         struct s3c2410_platform_nand    *platform;
113 
114         /* device info */
115         struct device                   *device;
116         struct resource                 *area;
117         struct clk                      *clk;
118         void __iomem                    *regs;
119         void __iomem                    *sel_reg;
120         int                             sel_bit;
121         int                             mtd_count;
122 
123         unsigned long                   save_nfconf;
124 
125         enum s3c_cpu_type               cpu_type;
126 };
127 
128 /* conversion functions */
129 
130 static struct s3c2410_nand_mtd *s3c2410_nand_mtd_toours(struct mtd_info *mtd)
131 {
132         return container_of(mtd, struct s3c2410_nand_mtd, mtd);
133 }
134 
135 static struct s3c2410_nand_info *s3c2410_nand_mtd_toinfo(struct mtd_info *mtd)
136 {
137         return s3c2410_nand_mtd_toours(mtd)->info;
138 }
139 
140 static struct s3c2410_nand_info *to_nand_info(struct platform_device *dev)
141 {
142         return platform_get_drvdata(dev);
143 }
144 
145 static struct s3c2410_platform_nand *to_nand_plat(struct platform_device *dev)
146 {
147         return dev->dev.platform_data;
148 }
149 
150 static inline int allow_clk_stop(struct s3c2410_nand_info *info)
151 {
152         return clock_stop;
153 }
154 
155 /* timing calculations */
156 
157 #define NS_IN_KHZ 1000000
158 
159 static int s3c_nand_calc_rate(int wanted, unsigned long clk, int max)
160 {
161         int result;
162 
163         result = (wanted * clk) / NS_IN_KHZ;
164         result++;
165 
166         pr_debug("result %d from %ld, %d\n", result, clk, wanted);
167 
168         if (result > max) {
169                 printk("%d ns is too big for current clock rate %ld\n", wanted, clk);
170                 return -1;
171         }
172 
173         if (result < 1)
174                 result = 1;
175 
176         return result;
177 }
178 
179 #define to_ns(ticks,clk) (((ticks) * NS_IN_KHZ) / (unsigned int)(clk))
180 
181 /* controller setup */
182 
183 static int s3c2410_nand_inithw(struct s3c2410_nand_info *info,
184                                struct platform_device *pdev)
185 {
186         struct s3c2410_platform_nand *plat = to_nand_plat(pdev);
187         unsigned long clkrate = clk_get_rate(info->clk);
188         int tacls_max = (info->cpu_type == TYPE_S3C2412) ? 8 : 4;
189         int tacls, twrph0, twrph1;
190         unsigned long cfg = 0;
191 
192         /* calculate the timing information for the controller */
193 
194         clkrate /= 1000;        /* turn clock into kHz for ease of use */
195 
196         if (plat != NULL) {
197                 tacls = s3c_nand_calc_rate(plat->tacls, clkrate, tacls_max);
198                 twrph0 = s3c_nand_calc_rate(plat->twrph0, clkrate, 8);
199                 twrph1 = s3c_nand_calc_rate(plat->twrph1, clkrate, 8);
200         } else {
201                 /* default timings */
202                 tacls = tacls_max;
203                 twrph0 = 8;
204                 twrph1 = 8;
205         }
206 
207         if (tacls < 0 || twrph0 < 0 || twrph1 < 0) {
208                 dev_err(info->device, "cannot get suitable timings\n");
209                 return -EINVAL;
210         }
211 
212         dev_info(info->device, "Tacls=%d, %dns Twrph0=%d %dns, Twrph1=%d %dns\n",
213                tacls, to_ns(tacls, clkrate), twrph0, to_ns(twrph0, clkrate), twrph1, to_ns(twrph1, clkrate));
214 
215         switch (info->cpu_type) {
216         case TYPE_S3C2410:
217                 cfg = S3C2410_NFCONF_EN;
218                 cfg |= S3C2410_NFCONF_TACLS(tacls - 1);
219                 cfg |= S3C2410_NFCONF_TWRPH0(twrph0 - 1);
220                 cfg |= S3C2410_NFCONF_TWRPH1(twrph1 - 1);
221                 break;
222 
223         case TYPE_S3C2440:
224         case TYPE_S3C2412:
225                 cfg = S3C2440_NFCONF_TACLS(tacls - 1);
226                 cfg |= S3C2440_NFCONF_TWRPH0(twrph0 - 1);
227                 cfg |= S3C2440_NFCONF_TWRPH1(twrph1 - 1);
228 
229                 /* enable the controller and de-assert nFCE */
230 
231                 writel(S3C2440_NFCONT_ENABLE, info->regs + S3C2440_NFCONT);
232         }
233 
234         dev_dbg(info->device, "NF_CONF is 0x%lx\n", cfg);
235 
236         writel(cfg, info->regs + S3C2410_NFCONF);
237         return 0;
238 }
239 
240 /* select chip */
241 
242 static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
243 {
244         struct s3c2410_nand_info *info;
245         struct s3c2410_nand_mtd *nmtd;
246         struct nand_chip *this = mtd->priv;
247         unsigned long cur;
248 
249         nmtd = this->priv;
250         info = nmtd->info;
251 
252         if (chip != -1 && allow_clk_stop(info))
253                 clk_enable(info->clk);
254 
255         cur = readl(info->sel_reg);
256 
257         if (chip == -1) {
258                 cur |= info->sel_bit;
259         } else {
260                 if (nmtd->set != NULL && chip > nmtd->set->nr_chips) {
261                         dev_err(info->device, "invalid chip %d\n", chip);
262                         return;
263                 }
264 
265                 if (info->platform != NULL) {
266                         if (info->platform->select_chip != NULL)
267                                 (info->platform->select_chip) (nmtd->set, chip);
268                 }
269 
270                 cur &= ~info->sel_bit;
271         }
272 
273         writel(cur, info->sel_reg);
274 
275         if (chip == -1 && allow_clk_stop(info))
276                 clk_disable(info->clk);
277 }
278 
279 /* s3c2410_nand_hwcontrol
280  *
281  * Issue command and address cycles to the chip
282 */
283 
284 static void s3c2410_nand_hwcontrol(struct mtd_info *mtd, int cmd,
285                                    unsigned int ctrl)
286 {
287         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
288 
289         if (cmd == NAND_CMD_NONE)
290                 return;
291 
292         if (ctrl & NAND_CLE)
293                 writeb(cmd, info->regs + S3C2410_NFCMD);
294         else
295                 writeb(cmd, info->regs + S3C2410_NFADDR);
296 }
297 
298 /* command and control functions */
299 
300 static void s3c2440_nand_hwcontrol(struct mtd_info *mtd, int cmd,
301                                    unsigned int ctrl)
302 {
303         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
304 
305         if (cmd == NAND_CMD_NONE)
306                 return;
307 
308         if (ctrl & NAND_CLE)
309                 writeb(cmd, info->regs + S3C2440_NFCMD);
310         else
311                 writeb(cmd, info->regs + S3C2440_NFADDR);
312 }
313 
314 /* s3c2410_nand_devready()
315  *
316  * returns 0 if the nand is busy, 1 if it is ready
317 */
318 
319 static int s3c2410_nand_devready(struct mtd_info *mtd)
320 {
321         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
322         return readb(info->regs + S3C2410_NFSTAT) & S3C2410_NFSTAT_BUSY;
323 }
324 
325 static int s3c2440_nand_devready(struct mtd_info *mtd)
326 {
327         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
328         return readb(info->regs + S3C2440_NFSTAT) & S3C2440_NFSTAT_READY;
329 }
330 
331 static int s3c2412_nand_devready(struct mtd_info *mtd)
332 {
333         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
334         return readb(info->regs + S3C2412_NFSTAT) & S3C2412_NFSTAT_READY;
335 }
336 
337 /* ECC handling functions */
338 
339 static int s3c2410_nand_correct_data(struct mtd_info *mtd, u_char *dat,
340                                      u_char *read_ecc, u_char *calc_ecc)
341 {
342         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
343         unsigned int diff0, diff1, diff2;
344         unsigned int bit, byte;
345 
346         pr_debug("%s(%p,%p,%p,%p)\n", __func__, mtd, dat, read_ecc, calc_ecc);
347 
348         diff0 = read_ecc[0] ^ calc_ecc[0];
349         diff1 = read_ecc[1] ^ calc_ecc[1];
350         diff2 = read_ecc[2] ^ calc_ecc[2];
351 
352         pr_debug("%s: rd %02x%02x%02x calc %02x%02x%02x diff %02x%02x%02x\n",
353                  __func__,
354                  read_ecc[0], read_ecc[1], read_ecc[2],
355                  calc_ecc[0], calc_ecc[1], calc_ecc[2],
356                  diff0, diff1, diff2);
357 
358         if (diff0 == 0 && diff1 == 0 && diff2 == 0)
359                 return 0;               /* ECC is ok */
360 
361         /* Can we correct this ECC (ie, one row and column change).
362          * Note, this is similar to the 256 error code on smartmedia */
363 
364         if (((diff0 ^ (diff0 >> 1)) & 0x55) == 0x55 &&
365             ((diff1 ^ (diff1 >> 1)) & 0x55) == 0x55 &&
366             ((diff2 ^ (diff2 >> 1)) & 0x55) == 0x55) {
367                 /* calculate the bit position of the error */
368 
369                 bit  = ((diff2 >> 3) & 1) |
370                        ((diff2 >> 4) & 2) |
371                        ((diff2 >> 5) & 4);
372 
373                 /* calculate the byte position of the error */
374 
375                 byte = ((diff2 << 7) & 0x100) |
376                        ((diff1 << 0) & 0x80)  |
377                        ((diff1 << 1) & 0x40)  |
378                        ((diff1 << 2) & 0x20)  |
379                        ((diff1 << 3) & 0x10)  |
380                        ((diff0 >> 4) & 0x08)  |
381                        ((diff0 >> 3) & 0x04)  |
382                        ((diff0 >> 2) & 0x02)  |
383                        ((diff0 >> 1) & 0x01);
384 
385                 dev_dbg(info->device, "correcting error bit %d, byte %d\n",
386                         bit, byte);
387 
388                 dat[byte] ^= (1 << bit);
389                 return 1;
390         }
391 
392         /* if there is only one bit difference in the ECC, then
393          * one of only a row or column parity has changed, which
394          * means the error is most probably in the ECC itself */
395 
396         diff0 |= (diff1 << 8);
397         diff0 |= (diff2 << 16);
398 
399         if ((diff0 & ~(1<<fls(diff0))) == 0)
400                 return 1;
401 
402         return -1;
403 }
404 
405 /* ECC functions
406  *
407  * These allow the s3c2410 and s3c2440 to use the controller's ECC
408  * generator block to ECC the data as it passes through]
409 */
410 
411 static void s3c2410_nand_enable_hwecc(struct mtd_info *mtd, int mode)
412 {
413         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
414         unsigned long ctrl;
415 
416         ctrl = readl(info->regs + S3C2410_NFCONF);
417         ctrl |= S3C2410_NFCONF_INITECC;
418         writel(ctrl, info->regs + S3C2410_NFCONF);
419 }
420 
421 static void s3c2412_nand_enable_hwecc(struct mtd_info *mtd, int mode)
422 {
423         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
424         unsigned long ctrl;
425 
426         ctrl = readl(info->regs + S3C2440_NFCONT);
427         writel(ctrl | S3C2412_NFCONT_INIT_MAIN_ECC, info->regs + S3C2440_NFCONT);
428 }
429 
430 static void s3c2440_nand_enable_hwecc(struct mtd_info *mtd, int mode)
431 {
432         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
433         unsigned long ctrl;
434 
435         ctrl = readl(info->regs + S3C2440_NFCONT);
436         writel(ctrl | S3C2440_NFCONT_INITECC, info->regs + S3C2440_NFCONT);
437 }
438 
439 static int s3c2410_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code)
440 {
441         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
442 
443         ecc_code[0] = readb(info->regs + S3C2410_NFECC + 0);
444         ecc_code[1] = readb(info->regs + S3C2410_NFECC + 1);
445         ecc_code[2] = readb(info->regs + S3C2410_NFECC + 2);
446 
447         pr_debug("%s: returning ecc %02x%02x%02x\n", __func__,
448                  ecc_code[0], ecc_code[1], ecc_code[2]);
449 
450         return 0;
451 }
452 
453 static int s3c2412_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code)
454 {
455         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
456         unsigned long ecc = readl(info->regs + S3C2412_NFMECC0);
457 
458         ecc_code[0] = ecc;
459         ecc_code[1] = ecc >> 8;
460         ecc_code[2] = ecc >> 16;
461 
462         pr_debug("calculate_ecc: returning ecc %02x,%02x,%02x\n", ecc_code[0], ecc_code[1], ecc_code[2]);
463 
464         return 0;
465 }
466 
467 static int s3c2440_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code)
468 {
469         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
470         unsigned long ecc = readl(info->regs + S3C2440_NFMECC0);
471 
472         ecc_code[0] = ecc;
473         ecc_code[1] = ecc >> 8;
474         ecc_code[2] = ecc >> 16;
475 
476         pr_debug("%s: returning ecc %06lx\n", __func__, ecc);
477 
478         return 0;
479 }
480 
481 /* over-ride the standard functions for a little more speed. We can
482  * use read/write block to move the data buffers to/from the controller
483 */
484 
485 static void s3c2410_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
486 {
487         struct nand_chip *this = mtd->priv;
488         readsb(this->IO_ADDR_R, buf, len);
489 }
490 
491 static void s3c2440_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
492 {
493         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
494         readsl(info->regs + S3C2440_NFDATA, buf, len / 4);
495 }
496 
497 static void s3c2410_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
498 {
499         struct nand_chip *this = mtd->priv;
500         writesb(this->IO_ADDR_W, buf, len);
501 }
502 
503 static void s3c2440_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
504 {
505         struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
506         writesl(info->regs + S3C2440_NFDATA, buf, len / 4);
507 }
508 
509 /* device management functions */
510 
511 static int s3c2410_nand_remove(struct platform_device *pdev)
512 {
513         struct s3c2410_nand_info *info = to_nand_info(pdev);
514 
515         platform_set_drvdata(pdev, NULL);
516 
517         if (info == NULL)
518                 return 0;
519 
520         /* first thing we need to do is release all our mtds
521          * and their partitions, then go through freeing the
522          * resources used
523          */
524 
525         if (info->mtds != NULL) {
526                 struct s3c2410_nand_mtd *ptr = info->mtds;
527                 int mtdno;
528 
529                 for (mtdno = 0; mtdno < info->mtd_count; mtdno++, ptr++) {
530                         pr_debug("releasing mtd %d (%p)\n", mtdno, ptr);
531                         nand_release(&ptr->mtd);
532                 }
533 
534                 kfree(info->mtds);
535         }
536 
537         /* free the common resources */
538 
539         if (info->clk != NULL && !IS_ERR(info->clk)) {
540                 if (!allow_clk_stop(info))
541                         clk_disable(info->clk);
542                 clk_put(info->clk);
543         }
544 
545         if (info->regs != NULL) {
546                 iounmap(info->regs);
547                 info->regs = NULL;
548         }
549 
550         if (info->area != NULL) {
551                 release_resource(info->area);
552                 kfree(info->area);
553                 info->area = NULL;
554         }
555 
556         kfree(info);
557 
558         return 0;
559 }
560 
561 #ifdef CONFIG_MTD_PARTITIONS
562 static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
563                                       struct s3c2410_nand_mtd *mtd,
564                                       struct s3c2410_nand_set *set)
565 {
566         if (set == NULL)
567                 return add_mtd_device(&mtd->mtd);
568 
569         if (set->nr_partitions > 0 && set->partitions != NULL) {
570                 return add_mtd_partitions(&mtd->mtd, set->partitions, set->nr_partitions);
571         }
572 
573         return add_mtd_device(&mtd->mtd);
574 }
575 #else
576 static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
577                                       struct s3c2410_nand_mtd *mtd,
578                                       struct s3c2410_nand_set *set)
579 {
580         return add_mtd_device(&mtd->mtd);
581 }
582 #endif
583 
584 /* s3c2410_nand_init_chip
585  *
586  * init a single instance of an chip
587 */
588 
589 static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
590                                    struct s3c2410_nand_mtd *nmtd,
591                                    struct s3c2410_nand_set *set)
592 {
593         struct nand_chip *chip = &nmtd->chip;
594         void __iomem *regs = info->regs;
595 
596         chip->write_buf    = s3c2410_nand_write_buf;
597         chip->read_buf     = s3c2410_nand_read_buf;
598         chip->select_chip  = s3c2410_nand_select_chip;
599         chip->chip_delay   = 50;
600         chip->priv         = nmtd;
601         chip->options      = 0;
602         chip->controller   = &info->controller;
603 
604         switch (info->cpu_type) {
605         case TYPE_S3C2410:
606                 chip->IO_ADDR_W = regs + S3C2410_NFDATA;
607                 info->sel_reg   = regs + S3C2410_NFCONF;
608                 info->sel_bit   = S3C2410_NFCONF_nFCE;
609                 chip->cmd_ctrl  = s3c2410_nand_hwcontrol;
610                 chip->dev_ready = s3c2410_nand_devready;
611                 break;
612 
613         case TYPE_S3C2440:
614                 chip->IO_ADDR_W = regs + S3C2440_NFDATA;
615                 info->sel_reg   = regs + S3C2440_NFCONT;
616                 info->sel_bit   = S3C2440_NFCONT_nFCE;
617                 chip->cmd_ctrl  = s3c2440_nand_hwcontrol;
618                 chip->dev_ready = s3c2440_nand_devready;
619                 chip->read_buf  = s3c2440_nand_read_buf;
620                 chip->write_buf = s3c2440_nand_write_buf;
621                 break;
622 
623         case TYPE_S3C2412:
624                 chip->IO_ADDR_W = regs + S3C2440_NFDATA;
625                 info->sel_reg   = regs + S3C2440_NFCONT;
626                 info->sel_bit   = S3C2412_NFCONT_nFCE0;
627                 chip->cmd_ctrl  = s3c2440_nand_hwcontrol;
628                 chip->dev_ready = s3c2412_nand_devready;
629 
630                 if (readl(regs + S3C2410_NFCONF) & S3C2412_NFCONF_NANDBOOT)
631                         dev_info(info->device, "System booted from NAND\n");
632 
633                 break;
634         }
635 
636         chip->IO_ADDR_R = chip->IO_ADDR_W;
637 
638         nmtd->info         = info;
639         nmtd->mtd.priv     = chip;
640         nmtd->mtd.owner    = THIS_MODULE;
641         nmtd->set          = set;
642 
643         if (hardware_ecc) {
644                 chip->ecc.calculate = s3c2410_nand_calculate_ecc;
645                 chip->ecc.correct   = s3c2410_nand_correct_data;
646                 chip->ecc.mode      = NAND_ECC_HW;
647                 chip->ecc.size      = 512;
648                 chip->ecc.bytes     = 3;
649                 chip->ecc.layout    = &nand_hw_eccoob;
650 
651                 switch (info->cpu_type) {
652                 case TYPE_S3C2410:
653                         chip->ecc.hwctl     = s3c2410_nand_enable_hwecc;
654                         chip->ecc.calculate = s3c2410_nand_calculate_ecc;
655                         break;
656 
657                 case TYPE_S3C2412:
658                         chip->ecc.hwctl     = s3c2412_nand_enable_hwecc;
659                         chip->ecc.calculate = s3c2412_nand_calculate_ecc;
660                         break;
661 
662                 case TYPE_S3C2440:
663                         chip->ecc.hwctl     = s3c2440_nand_enable_hwecc;
664                         chip->ecc.calculate = s3c2440_nand_calculate_ecc;
665                         break;
666 
667                 }
668         } else {
669                 chip->ecc.mode      = NAND_ECC_SOFT;
670         }
671 }
672 
673 /* s3c2410_nand_probe
674  *
675  * called by device layer when it finds a device matching
676  * one our driver can handled. This code checks to see if
677  * it can allocate all necessary resources then calls the
678  * nand layer to look for devices
679 */
680 
681 static int s3c24xx_nand_probe(struct platform_device *pdev,
682                               enum s3c_cpu_type cpu_type)
683 {
684         struct s3c2410_platform_nand *plat = to_nand_plat(pdev);
685         struct s3c2410_nand_info *info;
686         struct s3c2410_nand_mtd *nmtd;
687         struct s3c2410_nand_set *sets;
688         struct resource *res;
689         int err = 0;
690         int size;
691         int nr_sets;
692         int setno;
693 
694         pr_debug("s3c2410_nand_probe(%p)\n", pdev);
695 
696         info = kmalloc(sizeof(*info), GFP_KERNEL);
697         if (info == NULL) {
698                 dev_err(&pdev->dev, "no memory for flash info\n");
699                 err = -ENOMEM;
700                 goto exit_error;
701         }
702 
703         memzero(info, sizeof(*info));
704         platform_set_drvdata(pdev, info);
705 
706         spin_lock_init(&info->controller.lock);
707         init_waitqueue_head(&info->controller.wq);
708 
709         /* get the clock source and enable it */
710 
711         info->clk = clk_get(&pdev->dev, "nand");
712         if (IS_ERR(info->clk)) {
713                 dev_err(&pdev->dev, "failed to get clock\n");
714                 err = -ENOENT;
715                 goto exit_error;
716         }
717 
718         clk_enable(info->clk);
719 
720         /* allocate and map the resource */
721 
722         /* currently we assume we have the one resource */
723         res  = pdev->resource;
724         size = res->end - res->start + 1;
725 
726         info->area = request_mem_region(res->start, size, pdev->name);
727 
728         if (info->area == NULL) {
729                 dev_err(&pdev->dev, "cannot reserve register region\n");
730                 err = -ENOENT;
731                 goto exit_error;
732         }
733 
734         info->device     = &pdev->dev;
735         info->platform   = plat;
736         info->regs       = ioremap(res->start, size);
737         info->cpu_type   = cpu_type;
738 
739         if (info->regs == NULL) {
740                 dev_err(&pdev->dev, "cannot reserve register region\n");
741                 err = -EIO;
742                 goto exit_error;
743         }
744 
745         dev_dbg(&pdev->dev, "mapped registers at %p\n", info->regs);
746 
747         /* initialise the hardware */
748 
749         err = s3c2410_nand_inithw(info, pdev);
750         if (err != 0)
751                 goto exit_error;
752 
753         sets = (plat != NULL) ? plat->sets : NULL;
754         nr_sets = (plat != NULL) ? plat->nr_sets : 1;
755 
756         info->mtd_count = nr_sets;
757 
758         /* allocate our information */
759 
760         size = nr_sets * sizeof(*info->mtds);
761         info->mtds = kmalloc(size, GFP_KERNEL);
762         if (info->mtds == NULL) {
763                 dev_err(&pdev->dev, "failed to allocate mtd storage\n");
764                 err = -ENOMEM;
765                 goto exit_error;
766         }
767 
768         memzero(info->mtds, size);
769 
770         /* initialise all possible chips */
771 
772         nmtd = info->mtds;
773 
774         for (setno = 0; setno < nr_sets; setno++, nmtd++) {
775                 pr_debug("initialising set %d (%p, info %p)\n", setno, nmtd, info);
776 
777                 s3c2410_nand_init_chip(info, nmtd, sets);
778 
779                 nmtd->scan_res = nand_scan(&nmtd->mtd, (sets) ? sets->nr_chips : 1);
780 
781                 if (nmtd->scan_res == 0) {
782                         s3c2410_nand_add_partition(info, nmtd, sets);
783                 }
784 
785                 if (sets != NULL)
786                         sets++;
787         }
788 
789         if (allow_clk_stop(info)) {
790                 dev_info(&pdev->dev, "clock idle support enabled\n");
791                 clk_disable(info->clk);
792         }
793 
794         pr_debug("initialised ok\n");
795         return 0;
796 
797  exit_error:
798         s3c2410_nand_remove(pdev);
799 
800         if (err == 0)
801                 err = -EINVAL;
802         return err;
803 }
804 
805 /* PM Support */
806 #ifdef CONFIG_PM
807 
808 static int s3c24xx_nand_suspend(struct platform_device *dev, pm_message_t pm)
809 {
810         struct s3c2410_nand_info *info = platform_get_drvdata(dev);
811 
812         if (info) {
813                 info->save_nfconf = readl(info->regs + S3C2410_NFCONF);
814 
815                 /* For the moment, we must ensure nFCE is high during
816                  * the time we are suspended. This really should be
817                  * handled by suspending the MTDs we are using, but
818                  * that is currently not the case. */
819 
820                 writel(info->save_nfconf | info->sel_bit,
821                        info->regs + S3C2410_NFCONF);
822 
823                 if (!allow_clk_stop(info))
824                         clk_disable(info->clk);
825         }
826 
827         return 0;
828 }
829 
830 static int s3c24xx_nand_resume(struct platform_device *dev)
831 {
832         struct s3c2410_nand_info *info = platform_get_drvdata(dev);
833         unsigned long nfconf;
834 
835         if (info) {
836                 clk_enable(info->clk);
837                 s3c2410_nand_inithw(info, dev);
838 
839                 /* Restore the state of the nFCE line. */
840 
841                 nfconf = readl(info->regs + S3C2410_NFCONF);
842                 nfconf &= ~info->sel_bit;
843                 nfconf |= info->save_nfconf & info->sel_bit;
844                 writel(nfconf, info->regs + S3C2410_NFCONF);
845 
846                 if (allow_clk_stop(info))
847                         clk_disable(info->clk);
848         }
849 
850         return 0;
851 }
852 
853 #else
854 #define s3c24xx_nand_suspend NULL
855 #define s3c24xx_nand_resume NULL
856 #endif
857 
858 /* driver device registration */
859 
860 static int s3c2410_nand_probe(struct platform_device *dev)
861 {
862         return s3c24xx_nand_probe(dev, TYPE_S3C2410);
863 }
864 
865 static int s3c2440_nand_probe(struct platform_device *dev)
866 {
867         return s3c24xx_nand_probe(dev, TYPE_S3C2440);
868 }
869 
870 static int s3c2412_nand_probe(struct platform_device *dev)
871 {
872         return s3c24xx_nand_probe(dev, TYPE_S3C2412);
873 }
874 
875 static struct platform_driver s3c2410_nand_driver = {
876         .probe          = s3c2410_nand_probe,
877         .remove         = s3c2410_nand_remove,
878         .suspend        = s3c24xx_nand_suspend,
879         .resume         = s3c24xx_nand_resume,
880         .driver         = {
881                 .name   = "s3c2410-nand",
882                 .owner  = THIS_MODULE,
883         },
884 };
885 
886 static struct platform_driver s3c2440_nand_driver = {
887         .probe          = s3c2440_nand_probe,
888         .remove         = s3c2410_nand_remove,
889         .suspend        = s3c24xx_nand_suspend,
890         .resume         = s3c24xx_nand_resume,
891         .driver         = {
892                 .name   = "s3c2440-nand",
893                 .owner  = THIS_MODULE,
894         },
895 };
896 
897 static struct platform_driver s3c2412_nand_driver = {
898         .probe          = s3c2412_nand_probe,
899         .remove         = s3c2410_nand_remove,
900         .suspend        = s3c24xx_nand_suspend,
901         .resume         = s3c24xx_nand_resume,
902         .driver         = {
903                 .name   = "s3c2412-nand",
904                 .owner  = THIS_MODULE,
905         },
906 };
907 
908 static int __init s3c2410_nand_init(void)
909 {
910         printk("S3C24XX NAND Driver, (c) 2004 Simtec Electronics\n");
911 
912         platform_driver_register(&s3c2412_nand_driver);
913         platform_driver_register(&s3c2440_nand_driver);
914         return platform_driver_register(&s3c2410_nand_driver);
915 }
916 
917 static void __exit s3c2410_nand_exit(void)
918 {
919         platform_driver_unregister(&s3c2412_nand_driver);
920         platform_driver_unregister(&s3c2440_nand_driver);
921         platform_driver_unregister(&s3c2410_nand_driver);
922 }
923 
924 module_init(s3c2410_nand_init);
925 module_exit(s3c2410_nand_exit);
926 
927 MODULE_LICENSE("GPL");
928 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
929 MODULE_DESCRIPTION("S3C24XX MTD NAND driver");
930 
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