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Merge branch 'topic/misc' into for-linus
[deliverable/linux.git] / arch / arm / mach-s3c2412 / clock.c
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 .ops = &(struct clk_ops) {
128 .set_parent = s3c2412_setparent_usysclk,
129 },
130 };
131
132 static struct clk clk_mrefclk = {
133 .name = "mrefclk",
134 .parent = &clk_xtal,
135 .id = -1,
136 };
137
138 static struct clk clk_mdivclk = {
139 .name = "mdivclk",
140 .parent = &clk_xtal,
141 .id = -1,
142 };
143
144 static int s3c2412_setparent_usbsrc(struct clk *clk, struct clk *parent)
145 {
146 unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
147
148 if (parent == &clk_usysclk)
149 clksrc &= ~S3C2412_CLKSRC_USBCLK_HCLK;
150 else if (parent == &clk_h)
151 clksrc |= S3C2412_CLKSRC_USBCLK_HCLK;
152 else
153 return -EINVAL;
154
155 clk->parent = parent;
156
157 __raw_writel(clksrc, S3C2412_CLKSRC);
158 return 0;
159 }
160
161 static unsigned long s3c2412_roundrate_usbsrc(struct clk *clk,
162 unsigned long rate)
163 {
164 unsigned long parent_rate = clk_get_rate(clk->parent);
165 int div;
166
167 if (rate > parent_rate)
168 return parent_rate;
169
170 div = parent_rate / rate;
171 if (div > 2)
172 div = 2;
173
174 return parent_rate / div;
175 }
176
177 static unsigned long s3c2412_getrate_usbsrc(struct clk *clk)
178 {
179 unsigned long parent_rate = clk_get_rate(clk->parent);
180 unsigned long div = __raw_readl(S3C2410_CLKDIVN);
181
182 return parent_rate / ((div & S3C2412_CLKDIVN_USB48DIV) ? 2 : 1);
183 }
184
185 static int s3c2412_setrate_usbsrc(struct clk *clk, unsigned long rate)
186 {
187 unsigned long parent_rate = clk_get_rate(clk->parent);
188 unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN);
189
190 rate = s3c2412_roundrate_usbsrc(clk, rate);
191
192 if ((parent_rate / rate) == 2)
193 clkdivn |= S3C2412_CLKDIVN_USB48DIV;
194 else
195 clkdivn &= ~S3C2412_CLKDIVN_USB48DIV;
196
197 __raw_writel(clkdivn, S3C2410_CLKDIVN);
198 return 0;
199 }
200
201 static struct clk clk_usbsrc = {
202 .name = "usbsrc",
203 .id = -1,
204 .ops = &(struct clk_ops) {
205 .get_rate = s3c2412_getrate_usbsrc,
206 .set_rate = s3c2412_setrate_usbsrc,
207 .round_rate = s3c2412_roundrate_usbsrc,
208 .set_parent = s3c2412_setparent_usbsrc,
209 },
210 };
211
212 static int s3c2412_setparent_msysclk(struct clk *clk, struct clk *parent)
213 {
214 unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
215
216 if (parent == &clk_mdivclk)
217 clksrc &= ~S3C2412_CLKSRC_MSYSCLK_MPLL;
218 else if (parent == &clk_mpll)
219 clksrc |= S3C2412_CLKSRC_MSYSCLK_MPLL;
220 else
221 return -EINVAL;
222
223 clk->parent = parent;
224
225 __raw_writel(clksrc, S3C2412_CLKSRC);
226 return 0;
227 }
228
229 static struct clk clk_msysclk = {
230 .name = "msysclk",
231 .id = -1,
232 .ops = &(struct clk_ops) {
233 .set_parent = s3c2412_setparent_msysclk,
234 },
235 };
236
237 static int s3c2412_setparent_armclk(struct clk *clk, struct clk *parent)
238 {
239 unsigned long flags;
240 unsigned long clkdiv;
241 unsigned long dvs;
242
243 /* Note, we current equate fclk andf msysclk for S3C2412 */
244
245 if (parent == &clk_msysclk || parent == &clk_f)
246 dvs = 0;
247 else if (parent == &clk_h)
248 dvs = S3C2412_CLKDIVN_DVSEN;
249 else
250 return -EINVAL;
251
252 clk->parent = parent;
253
254 /* update this under irq lockdown, clkdivn is not protected
255 * by the clock system. */
256
257 local_irq_save(flags);
258
259 clkdiv = __raw_readl(S3C2410_CLKDIVN);
260 clkdiv &= ~S3C2412_CLKDIVN_DVSEN;
261 clkdiv |= dvs;
262 __raw_writel(clkdiv, S3C2410_CLKDIVN);
263
264 local_irq_restore(flags);
265
266 return 0;
267 }
268
269 static struct clk clk_armclk = {
270 .name = "armclk",
271 .id = -1,
272 .parent = &clk_msysclk,
273 .ops = &(struct clk_ops) {
274 .set_parent = s3c2412_setparent_armclk,
275 },
276 };
277
278 /* these next clocks have an divider immediately after them,
279 * so we can register them with their divider and leave out the
280 * intermediate clock stage
281 */
282 static unsigned long s3c2412_roundrate_clksrc(struct clk *clk,
283 unsigned long rate)
284 {
285 unsigned long parent_rate = clk_get_rate(clk->parent);
286 int div;
287
288 if (rate > parent_rate)
289 return parent_rate;
290
291 /* note, we remove the +/- 1 calculations as they cancel out */
292
293 div = (rate / parent_rate);
294
295 if (div < 1)
296 div = 1;
297 else if (div > 16)
298 div = 16;
299
300 return parent_rate / div;
301 }
302
303 static int s3c2412_setparent_uart(struct clk *clk, struct clk *parent)
304 {
305 unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
306
307 if (parent == &clk_erefclk)
308 clksrc &= ~S3C2412_CLKSRC_UARTCLK_MPLL;
309 else if (parent == &clk_mpll)
310 clksrc |= S3C2412_CLKSRC_UARTCLK_MPLL;
311 else
312 return -EINVAL;
313
314 clk->parent = parent;
315
316 __raw_writel(clksrc, S3C2412_CLKSRC);
317 return 0;
318 }
319
320 static unsigned long s3c2412_getrate_uart(struct clk *clk)
321 {
322 unsigned long parent_rate = clk_get_rate(clk->parent);
323 unsigned long div = __raw_readl(S3C2410_CLKDIVN);
324
325 div &= S3C2412_CLKDIVN_UARTDIV_MASK;
326 div >>= S3C2412_CLKDIVN_UARTDIV_SHIFT;
327
328 return parent_rate / (div + 1);
329 }
330
331 static int s3c2412_setrate_uart(struct clk *clk, unsigned long rate)
332 {
333 unsigned long parent_rate = clk_get_rate(clk->parent);
334 unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN);
335
336 rate = s3c2412_roundrate_clksrc(clk, rate);
337
338 clkdivn &= ~S3C2412_CLKDIVN_UARTDIV_MASK;
339 clkdivn |= ((parent_rate / rate) - 1) << S3C2412_CLKDIVN_UARTDIV_SHIFT;
340
341 __raw_writel(clkdivn, S3C2410_CLKDIVN);
342 return 0;
343 }
344
345 static struct clk clk_uart = {
346 .name = "uartclk",
347 .id = -1,
348 .ops = &(struct clk_ops) {
349 .get_rate = s3c2412_getrate_uart,
350 .set_rate = s3c2412_setrate_uart,
351 .set_parent = s3c2412_setparent_uart,
352 .round_rate = s3c2412_roundrate_clksrc,
353 },
354 };
355
356 static int s3c2412_setparent_i2s(struct clk *clk, struct clk *parent)
357 {
358 unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
359
360 if (parent == &clk_erefclk)
361 clksrc &= ~S3C2412_CLKSRC_I2SCLK_MPLL;
362 else if (parent == &clk_mpll)
363 clksrc |= S3C2412_CLKSRC_I2SCLK_MPLL;
364 else
365 return -EINVAL;
366
367 clk->parent = parent;
368
369 __raw_writel(clksrc, S3C2412_CLKSRC);
370 return 0;
371 }
372
373 static unsigned long s3c2412_getrate_i2s(struct clk *clk)
374 {
375 unsigned long parent_rate = clk_get_rate(clk->parent);
376 unsigned long div = __raw_readl(S3C2410_CLKDIVN);
377
378 div &= S3C2412_CLKDIVN_I2SDIV_MASK;
379 div >>= S3C2412_CLKDIVN_I2SDIV_SHIFT;
380
381 return parent_rate / (div + 1);
382 }
383
384 static int s3c2412_setrate_i2s(struct clk *clk, unsigned long rate)
385 {
386 unsigned long parent_rate = clk_get_rate(clk->parent);
387 unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN);
388
389 rate = s3c2412_roundrate_clksrc(clk, rate);
390
391 clkdivn &= ~S3C2412_CLKDIVN_I2SDIV_MASK;
392 clkdivn |= ((parent_rate / rate) - 1) << S3C2412_CLKDIVN_I2SDIV_SHIFT;
393
394 __raw_writel(clkdivn, S3C2410_CLKDIVN);
395 return 0;
396 }
397
398 static struct clk clk_i2s = {
399 .name = "i2sclk",
400 .id = -1,
401 .ops = &(struct clk_ops) {
402 .get_rate = s3c2412_getrate_i2s,
403 .set_rate = s3c2412_setrate_i2s,
404 .set_parent = s3c2412_setparent_i2s,
405 .round_rate = s3c2412_roundrate_clksrc,
406 },
407 };
408
409 static int s3c2412_setparent_cam(struct clk *clk, struct clk *parent)
410 {
411 unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
412
413 if (parent == &clk_usysclk)
414 clksrc &= ~S3C2412_CLKSRC_CAMCLK_HCLK;
415 else if (parent == &clk_h)
416 clksrc |= S3C2412_CLKSRC_CAMCLK_HCLK;
417 else
418 return -EINVAL;
419
420 clk->parent = parent;
421
422 __raw_writel(clksrc, S3C2412_CLKSRC);
423 return 0;
424 }
425 static unsigned long s3c2412_getrate_cam(struct clk *clk)
426 {
427 unsigned long parent_rate = clk_get_rate(clk->parent);
428 unsigned long div = __raw_readl(S3C2410_CLKDIVN);
429
430 div &= S3C2412_CLKDIVN_CAMDIV_MASK;
431 div >>= S3C2412_CLKDIVN_CAMDIV_SHIFT;
432
433 return parent_rate / (div + 1);
434 }
435
436 static int s3c2412_setrate_cam(struct clk *clk, unsigned long rate)
437 {
438 unsigned long parent_rate = clk_get_rate(clk->parent);
439 unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN);
440
441 rate = s3c2412_roundrate_clksrc(clk, rate);
442
443 clkdivn &= ~S3C2412_CLKDIVN_CAMDIV_MASK;
444 clkdivn |= ((parent_rate / rate) - 1) << S3C2412_CLKDIVN_CAMDIV_SHIFT;
445
446 __raw_writel(clkdivn, S3C2410_CLKDIVN);
447 return 0;
448 }
449
450 static struct clk clk_cam = {
451 .name = "camif-upll", /* same as 2440 name */
452 .id = -1,
453 .ops = &(struct clk_ops) {
454 .get_rate = s3c2412_getrate_cam,
455 .set_rate = s3c2412_setrate_cam,
456 .set_parent = s3c2412_setparent_cam,
457 .round_rate = s3c2412_roundrate_clksrc,
458 },
459 };
460
461 /* standard clock definitions */
462
463 static struct clk init_clocks_disable[] = {
464 {
465 .name = "nand",
466 .id = -1,
467 .parent = &clk_h,
468 .enable = s3c2412_clkcon_enable,
469 .ctrlbit = S3C2412_CLKCON_NAND,
470 }, {
471 .name = "sdi",
472 .id = -1,
473 .parent = &clk_p,
474 .enable = s3c2412_clkcon_enable,
475 .ctrlbit = S3C2412_CLKCON_SDI,
476 }, {
477 .name = "adc",
478 .id = -1,
479 .parent = &clk_p,
480 .enable = s3c2412_clkcon_enable,
481 .ctrlbit = S3C2412_CLKCON_ADC,
482 }, {
483 .name = "i2c",
484 .id = -1,
485 .parent = &clk_p,
486 .enable = s3c2412_clkcon_enable,
487 .ctrlbit = S3C2412_CLKCON_IIC,
488 }, {
489 .name = "iis",
490 .id = -1,
491 .parent = &clk_p,
492 .enable = s3c2412_clkcon_enable,
493 .ctrlbit = S3C2412_CLKCON_IIS,
494 }, {
495 .name = "spi",
496 .id = -1,
497 .parent = &clk_p,
498 .enable = s3c2412_clkcon_enable,
499 .ctrlbit = S3C2412_CLKCON_SPI,
500 }
501 };
502
503 static struct clk init_clocks[] = {
504 {
505 .name = "dma",
506 .id = 0,
507 .parent = &clk_h,
508 .enable = s3c2412_clkcon_enable,
509 .ctrlbit = S3C2412_CLKCON_DMA0,
510 }, {
511 .name = "dma",
512 .id = 1,
513 .parent = &clk_h,
514 .enable = s3c2412_clkcon_enable,
515 .ctrlbit = S3C2412_CLKCON_DMA1,
516 }, {
517 .name = "dma",
518 .id = 2,
519 .parent = &clk_h,
520 .enable = s3c2412_clkcon_enable,
521 .ctrlbit = S3C2412_CLKCON_DMA2,
522 }, {
523 .name = "dma",
524 .id = 3,
525 .parent = &clk_h,
526 .enable = s3c2412_clkcon_enable,
527 .ctrlbit = S3C2412_CLKCON_DMA3,
528 }, {
529 .name = "lcd",
530 .id = -1,
531 .parent = &clk_h,
532 .enable = s3c2412_clkcon_enable,
533 .ctrlbit = S3C2412_CLKCON_LCDC,
534 }, {
535 .name = "gpio",
536 .id = -1,
537 .parent = &clk_p,
538 .enable = s3c2412_clkcon_enable,
539 .ctrlbit = S3C2412_CLKCON_GPIO,
540 }, {
541 .name = "usb-host",
542 .id = -1,
543 .parent = &clk_h,
544 .enable = s3c2412_clkcon_enable,
545 .ctrlbit = S3C2412_CLKCON_USBH,
546 }, {
547 .name = "usb-device",
548 .id = -1,
549 .parent = &clk_h,
550 .enable = s3c2412_clkcon_enable,
551 .ctrlbit = S3C2412_CLKCON_USBD,
552 }, {
553 .name = "timers",
554 .id = -1,
555 .parent = &clk_p,
556 .enable = s3c2412_clkcon_enable,
557 .ctrlbit = S3C2412_CLKCON_PWMT,
558 }, {
559 .name = "uart",
560 .id = 0,
561 .parent = &clk_p,
562 .enable = s3c2412_clkcon_enable,
563 .ctrlbit = S3C2412_CLKCON_UART0,
564 }, {
565 .name = "uart",
566 .id = 1,
567 .parent = &clk_p,
568 .enable = s3c2412_clkcon_enable,
569 .ctrlbit = S3C2412_CLKCON_UART1,
570 }, {
571 .name = "uart",
572 .id = 2,
573 .parent = &clk_p,
574 .enable = s3c2412_clkcon_enable,
575 .ctrlbit = S3C2412_CLKCON_UART2,
576 }, {
577 .name = "rtc",
578 .id = -1,
579 .parent = &clk_p,
580 .enable = s3c2412_clkcon_enable,
581 .ctrlbit = S3C2412_CLKCON_RTC,
582 }, {
583 .name = "watchdog",
584 .id = -1,
585 .parent = &clk_p,
586 .ctrlbit = 0,
587 }, {
588 .name = "usb-bus-gadget",
589 .id = -1,
590 .parent = &clk_usb_bus,
591 .enable = s3c2412_clkcon_enable,
592 .ctrlbit = S3C2412_CLKCON_USB_DEV48,
593 }, {
594 .name = "usb-bus-host",
595 .id = -1,
596 .parent = &clk_usb_bus,
597 .enable = s3c2412_clkcon_enable,
598 .ctrlbit = S3C2412_CLKCON_USB_HOST48,
599 }
600 };
601
602 /* clocks to add where we need to check their parentage */
603
604 struct clk_init {
605 struct clk *clk;
606 unsigned int bit;
607 struct clk *src_0;
608 struct clk *src_1;
609 };
610
611 static struct clk_init clks_src[] __initdata = {
612 {
613 .clk = &clk_usysclk,
614 .bit = S3C2412_CLKSRC_USBCLK_HCLK,
615 .src_0 = &clk_urefclk,
616 .src_1 = &clk_upll,
617 }, {
618 .clk = &clk_i2s,
619 .bit = S3C2412_CLKSRC_I2SCLK_MPLL,
620 .src_0 = &clk_erefclk,
621 .src_1 = &clk_mpll,
622 }, {
623 .clk = &clk_cam,
624 .bit = S3C2412_CLKSRC_CAMCLK_HCLK,
625 .src_0 = &clk_usysclk,
626 .src_1 = &clk_h,
627 }, {
628 .clk = &clk_msysclk,
629 .bit = S3C2412_CLKSRC_MSYSCLK_MPLL,
630 .src_0 = &clk_mdivclk,
631 .src_1 = &clk_mpll,
632 }, {
633 .clk = &clk_uart,
634 .bit = S3C2412_CLKSRC_UARTCLK_MPLL,
635 .src_0 = &clk_erefclk,
636 .src_1 = &clk_mpll,
637 }, {
638 .clk = &clk_usbsrc,
639 .bit = S3C2412_CLKSRC_USBCLK_HCLK,
640 .src_0 = &clk_usysclk,
641 .src_1 = &clk_h,
642 /* here we assume OM[4] select xtal */
643 }, {
644 .clk = &clk_erefclk,
645 .bit = S3C2412_CLKSRC_EREFCLK_EXTCLK,
646 .src_0 = &clk_xtal,
647 .src_1 = &clk_ext,
648 }, {
649 .clk = &clk_urefclk,
650 .bit = S3C2412_CLKSRC_UREFCLK_EXTCLK,
651 .src_0 = &clk_xtal,
652 .src_1 = &clk_ext,
653 },
654 };
655
656 /* s3c2412_clk_initparents
657 *
658 * Initialise the parents for the clocks that we get at start-time
659 */
660
661 static void __init s3c2412_clk_initparents(void)
662 {
663 unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
664 struct clk_init *cip = clks_src;
665 struct clk *src;
666 int ptr;
667 int ret;
668
669 for (ptr = 0; ptr < ARRAY_SIZE(clks_src); ptr++, cip++) {
670 ret = s3c24xx_register_clock(cip->clk);
671 if (ret < 0) {
672 printk(KERN_ERR "Failed to register clock %s (%d)\n",
673 cip->clk->name, ret);
674 }
675
676 src = (clksrc & cip->bit) ? cip->src_1 : cip->src_0;
677
678 printk(KERN_INFO "%s: parent %s\n", cip->clk->name, src->name);
679 clk_set_parent(cip->clk, src);
680 }
681 }
682
683 /* clocks to add straight away */
684
685 static struct clk *clks[] __initdata = {
686 &clk_ext,
687 &clk_usb_bus,
688 &clk_mrefclk,
689 &clk_armclk,
690 };
691
692 int __init s3c2412_baseclk_add(void)
693 {
694 unsigned long clkcon = __raw_readl(S3C2410_CLKCON);
695 unsigned int dvs;
696 struct clk *clkp;
697 int ret;
698 int ptr;
699
700 clk_upll.enable = s3c2412_upll_enable;
701 clk_usb_bus.parent = &clk_usbsrc;
702 clk_usb_bus.rate = 0x0;
703
704 clk_f.parent = &clk_msysclk;
705
706 s3c2412_clk_initparents();
707
708 for (ptr = 0; ptr < ARRAY_SIZE(clks); ptr++) {
709 clkp = clks[ptr];
710
711 ret = s3c24xx_register_clock(clkp);
712 if (ret < 0) {
713 printk(KERN_ERR "Failed to register clock %s (%d)\n",
714 clkp->name, ret);
715 }
716 }
717
718 /* set the dvs state according to what we got at boot time */
719
720 dvs = __raw_readl(S3C2410_CLKDIVN) & S3C2412_CLKDIVN_DVSEN;
721
722 if (dvs)
723 clk_armclk.parent = &clk_h;
724
725 printk(KERN_INFO "S3C2412: DVS is %s\n", dvs ? "on" : "off");
726
727 /* ensure usb bus clock is within correct rate of 48MHz */
728
729 if (clk_get_rate(&clk_usb_bus) != (48 * 1000 * 1000)) {
730 printk(KERN_INFO "Warning: USB bus clock not at 48MHz\n");
731
732 /* for the moment, let's use the UPLL, and see if we can
733 * get 48MHz */
734
735 clk_set_parent(&clk_usysclk, &clk_upll);
736 clk_set_parent(&clk_usbsrc, &clk_usysclk);
737 clk_set_rate(&clk_usbsrc, 48*1000*1000);
738 }
739
740 printk("S3C2412: upll %s, %ld.%03ld MHz, usb-bus %ld.%03ld MHz\n",
741 (__raw_readl(S3C2410_UPLLCON) & S3C2412_PLLCON_OFF) ? "off":"on",
742 print_mhz(clk_get_rate(&clk_upll)),
743 print_mhz(clk_get_rate(&clk_usb_bus)));
744
745 /* register clocks from clock array */
746
747 clkp = init_clocks;
748 for (ptr = 0; ptr < ARRAY_SIZE(init_clocks); ptr++, clkp++) {
749 /* ensure that we note the clock state */
750
751 clkp->usage = clkcon & clkp->ctrlbit ? 1 : 0;
752
753 ret = s3c24xx_register_clock(clkp);
754 if (ret < 0) {
755 printk(KERN_ERR "Failed to register clock %s (%d)\n",
756 clkp->name, ret);
757 }
758 }
759
760 /* We must be careful disabling the clocks we are not intending to
761 * be using at boot time, as subsystems such as the LCD which do
762 * their own DMA requests to the bus can cause the system to lockup
763 * if they where in the middle of requesting bus access.
764 *
765 * Disabling the LCD clock if the LCD is active is very dangerous,
766 * and therefore the bootloader should be careful to not enable
767 * the LCD clock if it is not needed.
768 */
769
770 /* install (and disable) the clocks we do not need immediately */
771
772 clkp = init_clocks_disable;
773 for (ptr = 0; ptr < ARRAY_SIZE(init_clocks_disable); ptr++, clkp++) {
774
775 ret = s3c24xx_register_clock(clkp);
776 if (ret < 0) {
777 printk(KERN_ERR "Failed to register clock %s (%d)\n",
778 clkp->name, ret);
779 }
780
781 s3c2412_clkcon_enable(clkp, 0);
782 }
783
784 s3c_pwmclk_init();
785 return 0;
786 }
Linux kernel - Deliverables
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