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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/mach-s3c2410/clock.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/arm/mach-s3c2410/clock.c')
-rw-r--r--arch/arm/mach-s3c2410/clock.c507
1 files changed, 507 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c2410/clock.c b/arch/arm/mach-s3c2410/clock.c
new file mode 100644
index 000000000000..e23f534d4e1d
--- /dev/null
+++ b/arch/arm/mach-s3c2410/clock.c
@@ -0,0 +1,507 @@
1/* linux/arch/arm/mach-s3c2410/clock.c
2 *
3 * Copyright (c) 2004-2005 Simtec Electronics
4 * Ben Dooks <ben@simtec.co.uk>
5 *
6 * S3C2410 Clock control support
7 *
8 * Based on, and code from linux/arch/arm/mach-versatile/clock.c
9 **
10 ** Copyright (C) 2004 ARM Limited.
11 ** Written by Deep Blue Solutions Limited.
12 *
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
18 *
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
23 *
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, write to the Free Software
26 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
27*/
28
29#include <linux/init.h>
30#include <linux/module.h>
31#include <linux/kernel.h>
32#include <linux/list.h>
33#include <linux/errno.h>
34#include <linux/err.h>
35#include <linux/device.h>
36#include <linux/sysdev.h>
37
38#include <linux/interrupt.h>
39#include <linux/ioport.h>
40
41#include <asm/hardware.h>
42#include <asm/atomic.h>
43#include <asm/irq.h>
44#include <asm/io.h>
45
46#include <asm/hardware/clock.h>
47#include <asm/arch/regs-clock.h>
48
49#include "clock.h"
50#include "cpu.h"
51
52/* clock information */
53
54static LIST_HEAD(clocks);
55static DECLARE_MUTEX(clocks_sem);
56
57/* old functions */
58
59void inline s3c24xx_clk_enable(unsigned int clocks, unsigned int enable)
60{
61 unsigned long clkcon;
62 unsigned long flags;
63
64 local_irq_save(flags);
65
66 clkcon = __raw_readl(S3C2410_CLKCON);
67 clkcon &= ~clocks;
68
69 if (enable)
70 clkcon |= clocks;
71
72 /* ensure none of the special function bits set */
73 clkcon &= ~(S3C2410_CLKCON_IDLE|S3C2410_CLKCON_POWER);
74
75 __raw_writel(clkcon, S3C2410_CLKCON);
76
77 local_irq_restore(flags);
78}
79
80/* enable and disable calls for use with the clk struct */
81
82static int clk_null_enable(struct clk *clk, int enable)
83{
84 return 0;
85}
86
87int s3c24xx_clkcon_enable(struct clk *clk, int enable)
88{
89 s3c24xx_clk_enable(clk->ctrlbit, enable);
90 return 0;
91}
92
93/* Clock API calls */
94
95struct clk *clk_get(struct device *dev, const char *id)
96{
97 struct clk *p;
98 struct clk *clk = ERR_PTR(-ENOENT);
99 int idno;
100
101 idno = (dev == NULL) ? -1 : to_platform_device(dev)->id;
102
103 down(&clocks_sem);
104
105 list_for_each_entry(p, &clocks, list) {
106 if (p->id == idno &&
107 strcmp(id, p->name) == 0 &&
108 try_module_get(p->owner)) {
109 clk = p;
110 break;
111 }
112 }
113
114 /* check for the case where a device was supplied, but the
115 * clock that was being searched for is not device specific */
116
117 if (IS_ERR(clk)) {
118 list_for_each_entry(p, &clocks, list) {
119 if (p->id == -1 && strcmp(id, p->name) == 0 &&
120 try_module_get(p->owner)) {
121 clk = p;
122 break;
123 }
124 }
125 }
126
127 up(&clocks_sem);
128 return clk;
129}
130
131void clk_put(struct clk *clk)
132{
133 module_put(clk->owner);
134}
135
136int clk_enable(struct clk *clk)
137{
138 if (IS_ERR(clk))
139 return -EINVAL;
140
141 return (clk->enable)(clk, 1);
142}
143
144void clk_disable(struct clk *clk)
145{
146 if (!IS_ERR(clk))
147 (clk->enable)(clk, 0);
148}
149
150
151int clk_use(struct clk *clk)
152{
153 atomic_inc(&clk->used);
154 return 0;
155}
156
157
158void clk_unuse(struct clk *clk)
159{
160 atomic_dec(&clk->used);
161}
162
163unsigned long clk_get_rate(struct clk *clk)
164{
165 if (IS_ERR(clk))
166 return 0;
167
168 if (clk->rate != 0)
169 return clk->rate;
170
171 while (clk->parent != NULL && clk->rate == 0)
172 clk = clk->parent;
173
174 return clk->rate;
175}
176
177long clk_round_rate(struct clk *clk, unsigned long rate)
178{
179 return rate;
180}
181
182int clk_set_rate(struct clk *clk, unsigned long rate)
183{
184 return -EINVAL;
185}
186
187struct clk *clk_get_parent(struct clk *clk)
188{
189 return clk->parent;
190}
191
192EXPORT_SYMBOL(clk_get);
193EXPORT_SYMBOL(clk_put);
194EXPORT_SYMBOL(clk_enable);
195EXPORT_SYMBOL(clk_disable);
196EXPORT_SYMBOL(clk_use);
197EXPORT_SYMBOL(clk_unuse);
198EXPORT_SYMBOL(clk_get_rate);
199EXPORT_SYMBOL(clk_round_rate);
200EXPORT_SYMBOL(clk_set_rate);
201EXPORT_SYMBOL(clk_get_parent);
202
203/* base clocks */
204
205static struct clk clk_xtal = {
206 .name = "xtal",
207 .id = -1,
208 .rate = 0,
209 .parent = NULL,
210 .ctrlbit = 0,
211};
212
213static struct clk clk_f = {
214 .name = "fclk",
215 .id = -1,
216 .rate = 0,
217 .parent = NULL,
218 .ctrlbit = 0,
219};
220
221static struct clk clk_h = {
222 .name = "hclk",
223 .id = -1,
224 .rate = 0,
225 .parent = NULL,
226 .ctrlbit = 0,
227};
228
229static struct clk clk_p = {
230 .name = "pclk",
231 .id = -1,
232 .rate = 0,
233 .parent = NULL,
234 .ctrlbit = 0,
235};
236
237/* clocks that could be registered by external code */
238
239struct clk s3c24xx_dclk0 = {
240 .name = "dclk0",
241 .id = -1,
242};
243
244struct clk s3c24xx_dclk1 = {
245 .name = "dclk1",
246 .id = -1,
247};
248
249struct clk s3c24xx_clkout0 = {
250 .name = "clkout0",
251 .id = -1,
252};
253
254struct clk s3c24xx_clkout1 = {
255 .name = "clkout1",
256 .id = -1,
257};
258
259struct clk s3c24xx_uclk = {
260 .name = "uclk",
261 .id = -1,
262};
263
264
265/* clock definitions */
266
267static struct clk init_clocks[] = {
268 { .name = "nand",
269 .id = -1,
270 .parent = &clk_h,
271 .enable = s3c24xx_clkcon_enable,
272 .ctrlbit = S3C2410_CLKCON_NAND
273 },
274 { .name = "lcd",
275 .id = -1,
276 .parent = &clk_h,
277 .enable = s3c24xx_clkcon_enable,
278 .ctrlbit = S3C2410_CLKCON_LCDC
279 },
280 { .name = "usb-host",
281 .id = -1,
282 .parent = &clk_h,
283 .enable = s3c24xx_clkcon_enable,
284 .ctrlbit = S3C2410_CLKCON_USBH
285 },
286 { .name = "usb-device",
287 .id = -1,
288 .parent = &clk_h,
289 .enable = s3c24xx_clkcon_enable,
290 .ctrlbit = S3C2410_CLKCON_USBD
291 },
292 { .name = "timers",
293 .id = -1,
294 .parent = &clk_p,
295 .enable = s3c24xx_clkcon_enable,
296 .ctrlbit = S3C2410_CLKCON_PWMT
297 },
298 { .name = "sdi",
299 .id = -1,
300 .parent = &clk_p,
301 .enable = s3c24xx_clkcon_enable,
302 .ctrlbit = S3C2410_CLKCON_SDI
303 },
304 { .name = "uart",
305 .id = 0,
306 .parent = &clk_p,
307 .enable = s3c24xx_clkcon_enable,
308 .ctrlbit = S3C2410_CLKCON_UART0
309 },
310 { .name = "uart",
311 .id = 1,
312 .parent = &clk_p,
313 .enable = s3c24xx_clkcon_enable,
314 .ctrlbit = S3C2410_CLKCON_UART1
315 },
316 { .name = "uart",
317 .id = 2,
318 .parent = &clk_p,
319 .enable = s3c24xx_clkcon_enable,
320 .ctrlbit = S3C2410_CLKCON_UART2
321 },
322 { .name = "gpio",
323 .id = -1,
324 .parent = &clk_p,
325 .enable = s3c24xx_clkcon_enable,
326 .ctrlbit = S3C2410_CLKCON_GPIO
327 },
328 { .name = "rtc",
329 .id = -1,
330 .parent = &clk_p,
331 .enable = s3c24xx_clkcon_enable,
332 .ctrlbit = S3C2410_CLKCON_RTC
333 },
334 { .name = "adc",
335 .id = -1,
336 .parent = &clk_p,
337 .enable = s3c24xx_clkcon_enable,
338 .ctrlbit = S3C2410_CLKCON_ADC
339 },
340 { .name = "i2c",
341 .id = -1,
342 .parent = &clk_p,
343 .enable = s3c24xx_clkcon_enable,
344 .ctrlbit = S3C2410_CLKCON_IIC
345 },
346 { .name = "iis",
347 .id = -1,
348 .parent = &clk_p,
349 .enable = s3c24xx_clkcon_enable,
350 .ctrlbit = S3C2410_CLKCON_IIS
351 },
352 { .name = "spi",
353 .id = -1,
354 .parent = &clk_p,
355 .enable = s3c24xx_clkcon_enable,
356 .ctrlbit = S3C2410_CLKCON_SPI
357 },
358 { .name = "watchdog",
359 .id = -1,
360 .parent = &clk_p,
361 .ctrlbit = 0
362 }
363};
364
365/* initialise the clock system */
366
367int s3c24xx_register_clock(struct clk *clk)
368{
369 clk->owner = THIS_MODULE;
370 atomic_set(&clk->used, 0);
371
372 if (clk->enable == NULL)
373 clk->enable = clk_null_enable;
374
375 /* add to the list of available clocks */
376
377 down(&clocks_sem);
378 list_add(&clk->list, &clocks);
379 up(&clocks_sem);
380
381 return 0;
382}
383
384/* initalise all the clocks */
385
386int __init s3c24xx_setup_clocks(unsigned long xtal,
387 unsigned long fclk,
388 unsigned long hclk,
389 unsigned long pclk)
390{
391 struct clk *clkp = init_clocks;
392 int ptr;
393 int ret;
394
395 printk(KERN_INFO "S3C2410 Clocks, (c) 2004 Simtec Electronics\n");
396
397 /* initialise the main system clocks */
398
399 clk_xtal.rate = xtal;
400
401 clk_h.rate = hclk;
402 clk_p.rate = pclk;
403 clk_f.rate = fclk;
404
405 /* it looks like just setting the register here is not good
406 * enough, and causes the odd hang at initial boot time, so
407 * do all of them indivdually.
408 *
409 * I think disabling the LCD clock if the LCD is active is
410 * very dangerous, and therefore the bootloader should be
411 * careful to not enable the LCD clock if it is not needed.
412 *
413 * and of course, this looks neater
414 */
415
416 s3c24xx_clk_enable(S3C2410_CLKCON_NAND, 0);
417 s3c24xx_clk_enable(S3C2410_CLKCON_USBH, 0);
418 s3c24xx_clk_enable(S3C2410_CLKCON_USBD, 0);
419 s3c24xx_clk_enable(S3C2410_CLKCON_ADC, 0);
420 s3c24xx_clk_enable(S3C2410_CLKCON_IIC, 0);
421 s3c24xx_clk_enable(S3C2410_CLKCON_SPI, 0);
422
423 /* assume uart clocks are correctly setup */
424
425 /* register our clocks */
426
427 if (s3c24xx_register_clock(&clk_xtal) < 0)
428 printk(KERN_ERR "failed to register master xtal\n");
429
430 if (s3c24xx_register_clock(&clk_f) < 0)
431 printk(KERN_ERR "failed to register cpu fclk\n");
432
433 if (s3c24xx_register_clock(&clk_h) < 0)
434 printk(KERN_ERR "failed to register cpu hclk\n");
435
436 if (s3c24xx_register_clock(&clk_p) < 0)
437 printk(KERN_ERR "failed to register cpu pclk\n");
438
439 /* register clocks from clock array */
440
441 for (ptr = 0; ptr < ARRAY_SIZE(init_clocks); ptr++, clkp++) {
442 ret = s3c24xx_register_clock(clkp);
443 if (ret < 0) {
444 printk(KERN_ERR "Failed to register clock %s (%d)\n",
445 clkp->name, ret);
446 }
447 }
448
449 return 0;
450}
451
452/* S3C2440 extended clock support */
453
454#ifdef CONFIG_CPU_S3C2440
455
456static struct clk s3c2440_clk_upll = {
457 .name = "upll",
458 .id = -1,
459};
460
461static struct clk s3c2440_clk_cam = {
462 .name = "camif",
463 .parent = &clk_h,
464 .id = -1,
465 .enable = s3c24xx_clkcon_enable,
466 .ctrlbit = S3C2440_CLKCON_CAMERA,
467};
468
469static struct clk s3c2440_clk_ac97 = {
470 .name = "ac97",
471 .parent = &clk_p,
472 .id = -1,
473 .enable = s3c24xx_clkcon_enable,
474 .ctrlbit = S3C2440_CLKCON_CAMERA,
475};
476
477static int s3c2440_clk_add(struct sys_device *sysdev)
478{
479 unsigned long upllcon = __raw_readl(S3C2410_UPLLCON);
480
481 s3c2440_clk_upll.rate = s3c2410_get_pll(upllcon, clk_xtal.rate) * 2;
482
483 printk("S3C2440: Clock Support, UPLL %ld.%03ld MHz\n",
484 print_mhz(s3c2440_clk_upll.rate));
485
486 s3c24xx_register_clock(&s3c2440_clk_ac97);
487 s3c24xx_register_clock(&s3c2440_clk_cam);
488 s3c24xx_register_clock(&s3c2440_clk_upll);
489
490 clk_disable(&s3c2440_clk_ac97);
491 clk_disable(&s3c2440_clk_cam);
492
493 return 0;
494}
495
496static struct sysdev_driver s3c2440_clk_driver = {
497 .add = s3c2440_clk_add,
498};
499
500static int s3c24xx_clk_driver(void)
501{
502 return sysdev_driver_register(&s3c2440_sysclass, &s3c2440_clk_driver);
503}
504
505arch_initcall(s3c24xx_clk_driver);
506
507#endif /* CONFIG_CPU_S3C2440 */