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Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  1 /* linux/arch/arm/mach-s3c2412/clock.c
  2  *
  3  * Copyright (c) 2006 Simtec Electronics
  4  *      Ben Dooks <ben@simtec.co.uk>
  5  *
  6  * S3C2412,S3C2413 Clock control support
  7  *
  8  * This program is free software; you can redistribute it and/or modify
  9  * it under the terms of the GNU General Public License as published by
 10  * the Free Software Foundation; either version 2 of the License, or
 11  * (at your option) any later version.
 12  *
 13  * This program is distributed in the hope that it will be useful,
 14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 16  * GNU General Public License for more details.
 17  *
 18  * You should have received a copy of the GNU General Public License
 19  * along with this program; if not, write to the Free Software
 20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 21 */
 22 
 23 #include <linux/init.h>
 24 #include <linux/module.h>
 25 #include <linux/kernel.h>
 26 #include <linux/list.h>
 27 #include <linux/errno.h>
 28 #include <linux/err.h>
 29 #include <linux/sysdev.h>
 30 #include <linux/clk.h>
 31 #include <linux/mutex.h>
 32 #include <linux/delay.h>
 33 #include <linux/serial_core.h>
 34 #include <linux/io.h>
 35 
 36 #include <asm/mach/map.h>
 37 
 38 #include <mach/hardware.h>
 39 
 40 #include <plat/regs-serial.h>
 41 #include <mach/regs-clock.h>
 42 #include <mach/regs-gpio.h>
 43 
 44 #include <plat/s3c2412.h>
 45 #include <plat/clock.h>
 46 #include <plat/cpu.h>
 47 
 48 /* We currently have to assume that the system is running
 49  * from the XTPll input, and that all ***REFCLKs are being
 50  * fed from it, as we cannot read the state of OM[4] from
 51  * software.
 52  *
 53  * It would be possible for each board initialisation to
 54  * set the correct muxing at initialisation
 55 */
 56 
 57 static int s3c2412_clkcon_enable(struct clk *clk, int enable)
 58 {
 59         unsigned int clocks = clk->ctrlbit;
 60         unsigned long clkcon;
 61 
 62         clkcon = __raw_readl(S3C2410_CLKCON);
 63 
 64         if (enable)
 65                 clkcon |= clocks;
 66         else
 67                 clkcon &= ~clocks;
 68 
 69         __raw_writel(clkcon, S3C2410_CLKCON);
 70 
 71         return 0;
 72 }
 73 
 74 static int s3c2412_upll_enable(struct clk *clk, int enable)
 75 {
 76         unsigned long upllcon = __raw_readl(S3C2410_UPLLCON);
 77         unsigned long orig = upllcon;
 78 
 79         if (!enable)
 80                 upllcon |= S3C2412_PLLCON_OFF;
 81         else
 82                 upllcon &= ~S3C2412_PLLCON_OFF;
 83 
 84         __raw_writel(upllcon, S3C2410_UPLLCON);
 85 
 86         /* allow ~150uS for the PLL to settle and lock */
 87 
 88         if (enable && (orig & S3C2412_PLLCON_OFF))
 89                 udelay(150);
 90 
 91         return 0;
 92 }
 93 
 94 /* clock selections */
 95 
 96 static struct clk clk_erefclk = {
 97         .name           = "erefclk",
 98         .id             = -1,
 99 };
100 
101 static struct clk clk_urefclk = {
102         .name           = "urefclk",
103         .id             = -1,
104 };
105 
106 static int s3c2412_setparent_usysclk(struct clk *clk, struct clk *parent)
107 {
108         unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
109 
110         if (parent == &clk_urefclk)
111                 clksrc &= ~S3C2412_CLKSRC_USYSCLK_UPLL;
112         else if (parent == &clk_upll)
113                 clksrc |= S3C2412_CLKSRC_USYSCLK_UPLL;
114         else
115                 return -EINVAL;
116 
117         clk->parent = parent;
118 
119         __raw_writel(clksrc, S3C2412_CLKSRC);
120         return 0;
121 }
122 
123 static struct clk clk_usysclk = {
124         .name           = "usysclk",
125         .id             = -1,
126         .parent         = &clk_xtal,
127         .set_parent     = s3c2412_setparent_usysclk,
128 };
129 
130 static struct clk clk_mrefclk = {
131         .name           = "mrefclk",
132         .parent         = &clk_xtal,
133         .id             = -1,
134 };
135 
136 static struct clk clk_mdivclk = {
137         .name           = "mdivclk",
138         .parent         = &clk_xtal,
139         .id             = -1,
140 };
141 
142 static int s3c2412_setparent_usbsrc(struct clk *clk, struct clk *parent)
143 {
144         unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
145 
146         if (parent == &clk_usysclk)
147                 clksrc &= ~S3C2412_CLKSRC_USBCLK_HCLK;
148         else if (parent == &clk_h)
149                 clksrc |= S3C2412_CLKSRC_USBCLK_HCLK;
150         else
151                 return -EINVAL;
152 
153         clk->parent = parent;
154 
155         __raw_writel(clksrc, S3C2412_CLKSRC);
156         return 0;
157 }
158 
159 static unsigned long s3c2412_roundrate_usbsrc(struct clk *clk,
160                                               unsigned long rate)
161 {
162         unsigned long parent_rate = clk_get_rate(clk->parent);
163         int div;
164 
165         if (rate > parent_rate)
166                 return parent_rate;
167 
168         div = parent_rate / rate;
169         if (div > 2)
170                 div = 2;
171 
172         return parent_rate / div;
173 }
174 
175 static unsigned long s3c2412_getrate_usbsrc(struct clk *clk)
176 {
177         unsigned long parent_rate = clk_get_rate(clk->parent);
178         unsigned long div = __raw_readl(S3C2410_CLKDIVN);
179 
180         return parent_rate / ((div & S3C2412_CLKDIVN_USB48DIV) ? 2 : 1);
181 }
182 
183 static int s3c2412_setrate_usbsrc(struct clk *clk, unsigned long rate)
184 {
185         unsigned long parent_rate = clk_get_rate(clk->parent);
186         unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN);
187 
188         rate = s3c2412_roundrate_usbsrc(clk, rate);
189 
190         if ((parent_rate / rate) == 2)
191                 clkdivn |= S3C2412_CLKDIVN_USB48DIV;
192         else
193                 clkdivn &= ~S3C2412_CLKDIVN_USB48DIV;
194 
195         __raw_writel(clkdivn, S3C2410_CLKDIVN);
196         return 0;
197 }
198 
199 static struct clk clk_usbsrc = {
200         .name           = "usbsrc",
201         .id             = -1,
202         .get_rate       = s3c2412_getrate_usbsrc,
203         .set_rate       = s3c2412_setrate_usbsrc,
204         .round_rate     = s3c2412_roundrate_usbsrc,
205         .set_parent     = s3c2412_setparent_usbsrc,
206 };
207 
208 static int s3c2412_setparent_msysclk(struct clk *clk, struct clk *parent)
209 {
210         unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
211 
212         if (parent == &clk_mdivclk)
213                 clksrc &= ~S3C2412_CLKSRC_MSYSCLK_MPLL;
214         else if (parent == &clk_mpll)
215                 clksrc |= S3C2412_CLKSRC_MSYSCLK_MPLL;
216         else
217                 return -EINVAL;
218 
219         clk->parent = parent;
220 
221         __raw_writel(clksrc, S3C2412_CLKSRC);
222         return 0;
223 }
224 
225 static struct clk clk_msysclk = {
226         .name           = "msysclk",
227         .id             = -1,
228         .set_parent     = s3c2412_setparent_msysclk,
229 };
230 
231 static int s3c2412_setparent_armclk(struct clk *clk, struct clk *parent)
232 {
233         unsigned long flags;
234         unsigned long clkdiv;
235         unsigned long dvs;
236 
237         /* Note, we current equate fclk andf msysclk for S3C2412 */
238 
239         if (parent == &clk_msysclk || parent == &clk_f)
240                 dvs = 0;
241         else if (parent == &clk_h)
242                 dvs = S3C2412_CLKDIVN_DVSEN;
243         else
244                 return -EINVAL;
245 
246         clk->parent = parent;
247 
248         /* update this under irq lockdown, clkdivn is not protected
249          * by the clock system. */
250 
251         local_irq_save(flags);
252 
253         clkdiv  = __raw_readl(S3C2410_CLKDIVN);
254         clkdiv &= ~S3C2412_CLKDIVN_DVSEN;
255         clkdiv |= dvs;
256         __raw_writel(clkdiv, S3C2410_CLKDIVN);
257 
258         local_irq_restore(flags);
259 
260         return 0;
261 }
262 
263 static struct clk clk_armclk = {
264         .name           = "armclk",
265         .id             = -1,
266         .parent         = &clk_msysclk,
267         .set_parent     = s3c2412_setparent_armclk,
268 };
269 
270 /* these next clocks have an divider immediately after them,
271  * so we can register them with their divider and leave out the
272  * intermediate clock stage
273 */
274 static unsigned long s3c2412_roundrate_clksrc(struct clk *clk,
275                                               unsigned long rate)
276 {
277         unsigned long parent_rate = clk_get_rate(clk->parent);
278         int div;
279 
280         if (rate > parent_rate)
281                 return parent_rate;
282 
283         /* note, we remove the +/- 1 calculations as they cancel out */
284 
285         div = (rate / parent_rate);
286 
287         if (div < 1)
288                 div = 1;
289         else if (div > 16)
290                 div = 16;
291 
292         return parent_rate / div;
293 }
294 
295 static int s3c2412_setparent_uart(struct clk *clk, struct clk *parent)
296 {
297         unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
298 
299         if (parent == &clk_erefclk)
300                 clksrc &= ~S3C2412_CLKSRC_UARTCLK_MPLL;
301         else if (parent == &clk_mpll)
302                 clksrc |= S3C2412_CLKSRC_UARTCLK_MPLL;
303         else
304                 return -EINVAL;
305 
306         clk->parent = parent;
307 
308         __raw_writel(clksrc, S3C2412_CLKSRC);
309         return 0;
310 }
311 
312 static unsigned long s3c2412_getrate_uart(struct clk *clk)
313 {
314         unsigned long parent_rate = clk_get_rate(clk->parent);
315         unsigned long div = __raw_readl(S3C2410_CLKDIVN);
316 
317         div &= S3C2412_CLKDIVN_UARTDIV_MASK;
318         div >>= S3C2412_CLKDIVN_UARTDIV_SHIFT;
319 
320         return parent_rate / (div + 1);
321 }
322 
323 static int s3c2412_setrate_uart(struct clk *clk, unsigned long rate)
324 {
325         unsigned long parent_rate = clk_get_rate(clk->parent);
326         unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN);
327 
328         rate = s3c2412_roundrate_clksrc(clk, rate);
329 
330         clkdivn &= ~S3C2412_CLKDIVN_UARTDIV_MASK;
331         clkdivn |= ((parent_rate / rate) - 1) << S3C2412_CLKDIVN_UARTDIV_SHIFT;
332 
333         __raw_writel(clkdivn, S3C2410_CLKDIVN);
334         return 0;
335 }
336 
337 static struct clk clk_uart = {
338         .name           = "uartclk",
339         .id             = -1,
340         .get_rate       = s3c2412_getrate_uart,
341         .set_rate       = s3c2412_setrate_uart,
342         .set_parent     = s3c2412_setparent_uart,
343         .round_rate     = s3c2412_roundrate_clksrc,
344 };
345 
346 static int s3c2412_setparent_i2s(struct clk *clk, struct clk *parent)
347 {
348         unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
349 
350         if (parent == &clk_erefclk)
351                 clksrc &= ~S3C2412_CLKSRC_I2SCLK_MPLL;
352         else if (parent == &clk_mpll)
353                 clksrc |= S3C2412_CLKSRC_I2SCLK_MPLL;
354         else
355                 return -EINVAL;
356 
357         clk->parent = parent;
358 
359         __raw_writel(clksrc, S3C2412_CLKSRC);
360         return 0;
361 }
362 
363 static unsigned long s3c2412_getrate_i2s(struct clk *clk)
364 {
365         unsigned long parent_rate = clk_get_rate(clk->parent);
366         unsigned long div = __raw_readl(S3C2410_CLKDIVN);
367 
368         div &= S3C2412_CLKDIVN_I2SDIV_MASK;
369         div >>= S3C2412_CLKDIVN_I2SDIV_SHIFT;
370 
371         return parent_rate / (div + 1);
372 }
373 
374 static int s3c2412_setrate_i2s(struct clk *clk, unsigned long rate)
375 {
376         unsigned long parent_rate = clk_get_rate(clk->parent);
377         unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN);
378 
379         rate = s3c2412_roundrate_clksrc(clk, rate);
380 
381         clkdivn &= ~S3C2412_CLKDIVN_I2SDIV_MASK;
382         clkdivn |= ((parent_rate / rate) - 1) << S3C2412_CLKDIVN_I2SDIV_SHIFT;
383 
384         __raw_writel(clkdivn, S3C2410_CLKDIVN);
385         return 0;
386 }
387 
388 static struct clk clk_i2s = {
389         .name           = "i2sclk",
390         .id             = -1,
391         .get_rate       = s3c2412_getrate_i2s,
392         .set_rate       = s3c2412_setrate_i2s,
393         .set_parent     = s3c2412_setparent_i2s,
394         .round_rate     = s3c2412_roundrate_clksrc,
395 };
396 
397 static int s3c2412_setparent_cam(struct clk *clk, struct clk *parent)
398 {
399         unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
400 
401         if (parent == &clk_usysclk)
402                 clksrc &= ~S3C2412_CLKSRC_CAMCLK_HCLK;
403         else if (parent == &clk_h)
404                 clksrc |= S3C2412_CLKSRC_CAMCLK_HCLK;
405         else
406                 return -EINVAL;
407 
408         clk->parent = parent;
409 
410         __raw_writel(clksrc, S3C2412_CLKSRC);
411         return 0;
412 }
413 static unsigned long s3c2412_getrate_cam(struct clk *clk)
414 {
415         unsigned long parent_rate = clk_get_rate(clk->parent);
416         unsigned long div = __raw_readl(S3C2410_CLKDIVN);
417 
418         div &= S3C2412_CLKDIVN_CAMDIV_MASK;
419         div >>= S3C2412_CLKDIVN_CAMDIV_SHIFT;
420 
421         return parent_rate / (div + 1);
422 }
423 
424 static int s3c2412_setrate_cam(struct clk *clk, unsigned long rate)
425 {
426         unsigned long parent_rate = clk_get_rate(clk->parent);
427         unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN);
428 
429         rate = s3c2412_roundrate_clksrc(clk, rate);
430 
431         clkdivn &= ~S3C2412_CLKDIVN_CAMDIV_MASK;
432         clkdivn |= ((parent_rate / rate) - 1) << S3C2412_CLKDIVN_CAMDIV_SHIFT;
433 
434         __raw_writel(clkdivn, S3C2410_CLKDIVN);
435         return 0;
436 }
437 
438 static struct clk clk_cam = {
439         .name           = "camif-upll", /* same as 2440 name */
440         .id             = -1,
441         .get_rate       = s3c2412_getrate_cam,
442         .set_rate       = s3c2412_setrate_cam,
443         .set_parent     = s3c2412_setparent_cam,
444         .round_rate     = s3c2412_roundrate_clksrc,
445 };
446 
447 /* standard clock definitions */
448 
449 static struct clk init_clocks_disable[] = {
450         {
451                 .name           = "nand",
452                 .id             = -1,
453                 .parent         = &clk_h,
454                 .enable         = s3c2412_clkcon_enable,
455                 .ctrlbit        = S3C2412_CLKCON_NAND,
456         }, {
457                 .name           = "sdi",
458                 .id             = -1,
459                 .parent         = &clk_p,
460                 .enable         = s3c2412_clkcon_enable,
461                 .ctrlbit        = S3C2412_CLKCON_SDI,
462         }, {
463                 .name           = "adc",
464                 .id             = -1,
465                 .parent         = &clk_p,
466                 .enable         = s3c2412_clkcon_enable,
467                 .ctrlbit        = S3C2412_CLKCON_ADC,
468         }, {
469                 .name           = "i2c",
470                 .id             = -1,
471                 .parent         = &clk_p,
472                 .enable         = s3c2412_clkcon_enable,
473                 .ctrlbit        = S3C2412_CLKCON_IIC,
474         }, {
475                 .name           = "iis",
476                 .id             = -1,
477                 .parent         = &clk_p,
478                 .enable         = s3c2412_clkcon_enable,
479                 .ctrlbit        = S3C2412_CLKCON_IIS,
480         }, {
481                 .name           = "spi",
482                 .id             = -1,
483                 .parent         = &clk_p,
484                 .enable         = s3c2412_clkcon_enable,
485                 .ctrlbit        = S3C2412_CLKCON_SPI,
486         }
487 };
488 
489 static struct clk init_clocks[] = {
490         {
491                 .name           = "dma",
492                 .id             = 0,
493                 .parent         = &clk_h,
494                 .enable         = s3c2412_clkcon_enable,
495                 .ctrlbit        = S3C2412_CLKCON_DMA0,
496         }, {
497                 .name           = "dma",
498                 .id             = 1,
499                 .parent         = &clk_h,
500                 .enable         = s3c2412_clkcon_enable,
501                 .ctrlbit        = S3C2412_CLKCON_DMA1,
502         }, {
503                 .name           = "dma",
504                 .id             = 2,
505                 .parent         = &clk_h,
506                 .enable         = s3c2412_clkcon_enable,
507                 .ctrlbit        = S3C2412_CLKCON_DMA2,
508         }, {
509                 .name           = "dma",
510                 .id             = 3,
511                 .parent         = &clk_h,
512                 .enable         = s3c2412_clkcon_enable,
513                 .ctrlbit        = S3C2412_CLKCON_DMA3,
514         }, {
515                 .name           = "lcd",
516                 .id             = -1,
517                 .parent         = &clk_h,
518                 .enable         = s3c2412_clkcon_enable,
519                 .ctrlbit        = S3C2412_CLKCON_LCDC,
520         }, {
521                 .name           = "gpio",
522                 .id             = -1,
523                 .parent         = &clk_p,
524                 .enable         = s3c2412_clkcon_enable,
525                 .ctrlbit        = S3C2412_CLKCON_GPIO,
526         }, {
527                 .name           = "usb-host",
528                 .id             = -1,
529                 .parent         = &clk_h,
530                 .enable         = s3c2412_clkcon_enable,
531                 .ctrlbit        = S3C2412_CLKCON_USBH,
532         }, {
533                 .name           = "usb-device",
534                 .id             = -1,
535                 .parent         = &clk_h,
536                 .enable         = s3c2412_clkcon_enable,
537                 .ctrlbit        = S3C2412_CLKCON_USBD,
538         }, {
539                 .name           = "timers",
540                 .id             = -1,
541                 .parent         = &clk_p,
542                 .enable         = s3c2412_clkcon_enable,
543                 .ctrlbit        = S3C2412_CLKCON_PWMT,
544         }, {
545                 .name           = "uart",
546                 .id             = 0,
547                 .parent         = &clk_p,
548                 .enable         = s3c2412_clkcon_enable,
549                 .ctrlbit        = S3C2412_CLKCON_UART0,
550         }, {
551                 .name           = "uart",
552                 .id             = 1,
553                 .parent         = &clk_p,
554                 .enable         = s3c2412_clkcon_enable,
555                 .ctrlbit        = S3C2412_CLKCON_UART1,
556         }, {
557                 .name           = "uart",
558                 .id             = 2,
559                 .parent         = &clk_p,
560                 .enable         = s3c2412_clkcon_enable,
561                 .ctrlbit        = S3C2412_CLKCON_UART2,
562         }, {
563                 .name           = "rtc",
564                 .id             = -1,
565                 .parent         = &clk_p,
566                 .enable         = s3c2412_clkcon_enable,
567                 .ctrlbit        = S3C2412_CLKCON_RTC,
568         }, {
569                 .name           = "watchdog",
570                 .id             = -1,
571                 .parent         = &clk_p,
572                 .ctrlbit        = 0,
573         }, {
574                 .name           = "usb-bus-gadget",
575                 .id             = -1,
576                 .parent         = &clk_usb_bus,
577                 .enable         = s3c2412_clkcon_enable,
578                 .ctrlbit        = S3C2412_CLKCON_USB_DEV48,
579         }, {
580                 .name           = "usb-bus-host",
581                 .id             = -1,
582                 .parent         = &clk_usb_bus,
583                 .enable         = s3c2412_clkcon_enable,
584                 .ctrlbit        = S3C2412_CLKCON_USB_HOST48,
585         }
586 };
587 
588 /* clocks to add where we need to check their parentage */
589 
590 struct clk_init {
591         struct clk      *clk;
592         unsigned int     bit;
593         struct clk      *src_0;
594         struct clk      *src_1;
595 };
596 
597 static struct clk_init clks_src[] __initdata = {
598         {
599                 .clk    = &clk_usysclk,
600                 .bit    = S3C2412_CLKSRC_USBCLK_HCLK,
601                 .src_0  = &clk_urefclk,
602                 .src_1  = &clk_upll,
603         }, {
604                 .clk    = &clk_i2s,
605                 .bit    = S3C2412_CLKSRC_I2SCLK_MPLL,
606                 .src_0  = &clk_erefclk,
607                 .src_1  = &clk_mpll,
608         }, {
609                 .clk    = &clk_cam,
610                 .bit    = S3C2412_CLKSRC_CAMCLK_HCLK,
611                 .src_0  = &clk_usysclk,
612                 .src_1  = &clk_h,
613         }, {
614                 .clk    = &clk_msysclk,
615                 .bit    = S3C2412_CLKSRC_MSYSCLK_MPLL,
616                 .src_0  = &clk_mdivclk,
617                 .src_1  = &clk_mpll,
618         }, {
619                 .clk    = &clk_uart,
620                 .bit    = S3C2412_CLKSRC_UARTCLK_MPLL,
621                 .src_0  = &clk_erefclk,
622                 .src_1  = &clk_mpll,
623         }, {
624                 .clk    = &clk_usbsrc,
625                 .bit    = S3C2412_CLKSRC_USBCLK_HCLK,
626                 .src_0  = &clk_usysclk,
627                 .src_1  = &clk_h,
628         /* here we assume  OM[4] select xtal */
629         }, {
630                 .clk    = &clk_erefclk,
631                 .bit    = S3C2412_CLKSRC_EREFCLK_EXTCLK,
632                 .src_0  = &clk_xtal,
633                 .src_1  = &clk_ext,
634         }, {
635                 .clk    = &clk_urefclk,
636                 .bit    = S3C2412_CLKSRC_UREFCLK_EXTCLK,
637                 .src_0  = &clk_xtal,
638                 .src_1  = &clk_ext,
639         },
640 };
641 
642 /* s3c2412_clk_initparents
643  *
644  * Initialise the parents for the clocks that we get at start-time
645 */
646 
647 static void __init s3c2412_clk_initparents(void)
648 {
649         unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
650         struct clk_init *cip = clks_src;
651         struct clk *src;
652         int ptr;
653         int ret;
654 
655         for (ptr = 0; ptr < ARRAY_SIZE(clks_src); ptr++, cip++) {
656                 ret = s3c24xx_register_clock(cip->clk);
657                 if (ret < 0) {
658                         printk(KERN_ERR "Failed to register clock %s (%d)\n",
659                                cip->clk->name, ret);
660                 }
661 
662                 src = (clksrc & cip->bit) ? cip->src_1 : cip->src_0;
663 
664                 printk(KERN_INFO "%s: parent %s\n", cip->clk->name, src->name);
665                 clk_set_parent(cip->clk, src);
666         }
667 }
668 
669 /* clocks to add straight away */
670 
671 static struct clk *clks[] __initdata = {
672         &clk_ext,
673         &clk_usb_bus,
674         &clk_mrefclk,
675         &clk_armclk,
676 };
677 
678 int __init s3c2412_baseclk_add(void)
679 {
680         unsigned long clkcon  = __raw_readl(S3C2410_CLKCON);
681         unsigned int dvs;
682         struct clk *clkp;
683         int ret;
684         int ptr;
685 
686         clk_upll.enable = s3c2412_upll_enable;
687         clk_usb_bus.parent = &clk_usbsrc;
688         clk_usb_bus.rate = 0x0;
689 
690         clk_f.parent = &clk_msysclk;
691 
692         s3c2412_clk_initparents();
693 
694         for (ptr = 0; ptr < ARRAY_SIZE(clks); ptr++) {
695                 clkp = clks[ptr];
696 
697                 ret = s3c24xx_register_clock(clkp);
698                 if (ret < 0) {
699                         printk(KERN_ERR "Failed to register clock %s (%d)\n",
700                                clkp->name, ret);
701                 }
702         }
703 
704         /* set the dvs state according to what we got at boot time */
705 
706         dvs = __raw_readl(S3C2410_CLKDIVN) & S3C2412_CLKDIVN_DVSEN;
707 
708         if (dvs)
709                 clk_armclk.parent = &clk_h;
710 
711         printk(KERN_INFO "S3C2412: DVS is %s\n", dvs ? "on" : "off");
712 
713         /* ensure usb bus clock is within correct rate of 48MHz */
714 
715         if (clk_get_rate(&clk_usb_bus) != (48 * 1000 * 1000)) {
716                 printk(KERN_INFO "Warning: USB bus clock not at 48MHz\n");
717 
718                 /* for the moment, let's use the UPLL, and see if we can
719                  * get 48MHz */
720 
721                 clk_set_parent(&clk_usysclk, &clk_upll);
722                 clk_set_parent(&clk_usbsrc, &clk_usysclk);
723                 clk_set_rate(&clk_usbsrc, 48*1000*1000);
724         }
725 
726         printk("S3C2412: upll %s, %ld.%03ld MHz, usb-bus %ld.%03ld MHz\n",
727                (__raw_readl(S3C2410_UPLLCON) & S3C2412_PLLCON_OFF) ? "off":"on",
728                print_mhz(clk_get_rate(&clk_upll)),
729                print_mhz(clk_get_rate(&clk_usb_bus)));
730 
731         /* register clocks from clock array */
732 
733         clkp = init_clocks;
734         for (ptr = 0; ptr < ARRAY_SIZE(init_clocks); ptr++, clkp++) {
735                 /* ensure that we note the clock state */
736 
737                 clkp->usage = clkcon & clkp->ctrlbit ? 1 : 0;
738 
739                 ret = s3c24xx_register_clock(clkp);
740                 if (ret < 0) {
741                         printk(KERN_ERR "Failed to register clock %s (%d)\n",
742                                clkp->name, ret);
743                 }
744         }
745 
746         /* We must be careful disabling the clocks we are not intending to
747          * be using at boot time, as subsystems such as the LCD which do
748          * their own DMA requests to the bus can cause the system to lockup
749          * if they where in the middle of requesting bus access.
750          *
751          * Disabling the LCD clock if the LCD is active is very dangerous,
752          * and therefore the bootloader should be careful to not enable
753          * the LCD clock if it is not needed.
754         */
755 
756         /* install (and disable) the clocks we do not need immediately */
757 
758         clkp = init_clocks_disable;
759         for (ptr = 0; ptr < ARRAY_SIZE(init_clocks_disable); ptr++, clkp++) {
760 
761                 ret = s3c24xx_register_clock(clkp);
762                 if (ret < 0) {
763                         printk(KERN_ERR "Failed to register clock %s (%d)\n",
764                                clkp->name, ret);
765                 }
766 
767                 s3c2412_clkcon_enable(clkp, 0);
768         }
769 
770         s3c_pwmclk_init();
771         return 0;
772 }
773 
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