blob: 10f71179071f9b2db939764804401568309d801d [file] [log] [blame]
Ben Dooksadbefaa2008-10-21 14:06:54 +01001/* linux/arch/arm/plat-s3c24xx/clock.c
2 *
Ben Dooks50f430e2009-11-13 22:54:12 +00003 * Copyright 2004-2005 Simtec Electronics
Ben Dooksadbefaa2008-10-21 14:06:54 +01004 * Ben Dooks <ben@simtec.co.uk>
5 *
6 * S3C24XX Core 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/platform_device.h>
Kay Sieversedbaa602011-12-21 16:26:03 -080036#include <linux/device.h>
Ben Dooksadbefaa2008-10-21 14:06:54 +010037#include <linux/interrupt.h>
38#include <linux/ioport.h>
39#include <linux/clk.h>
40#include <linux/spinlock.h>
Ben Dooksadbefaa2008-10-21 14:06:54 +010041#include <linux/io.h>
Amit Daniel Kachhap436c3872011-01-12 13:40:04 +090042#if defined(CONFIG_DEBUG_FS)
43#include <linux/debugfs.h>
44#endif
Ben Dooksadbefaa2008-10-21 14:06:54 +010045
46#include <mach/hardware.h>
47#include <asm/irq.h>
48
49#include <plat/cpu-freq.h>
50
51#include <plat/clock.h>
52#include <plat/cpu.h>
53
Marek Szyprowski7cf4b482010-10-07 17:19:10 +090054#include <linux/serial_core.h>
55#include <plat/regs-serial.h> /* for s3c24xx_uart_devs */
56
Ben Dooksadbefaa2008-10-21 14:06:54 +010057/* clock information */
58
59static LIST_HEAD(clocks);
60
61/* We originally used an mutex here, but some contexts (see resume)
62 * are calling functions such as clk_set_parent() with IRQs disabled
63 * causing an BUG to be triggered.
64 */
65DEFINE_SPINLOCK(clocks_lock);
66
Marek Szyprowskicaf27302011-09-05 20:10:06 +090067/* Global watchdog clock used by arch_wtd_reset() callback */
68struct clk *s3c2410_wdtclk;
69static int __init s3c_wdt_reset_init(void)
70{
71 s3c2410_wdtclk = clk_get(NULL, "watchdog");
72 if (IS_ERR(s3c2410_wdtclk))
73 printk(KERN_WARNING "%s: warning: cannot get watchdog clock\n", __func__);
74 return 0;
75}
76arch_initcall(s3c_wdt_reset_init);
77
Ben Dooksadbefaa2008-10-21 14:06:54 +010078/* enable and disable calls for use with the clk struct */
79
80static int clk_null_enable(struct clk *clk, int enable)
81{
82 return 0;
83}
84
Ben Dooksadbefaa2008-10-21 14:06:54 +010085int clk_enable(struct clk *clk)
86{
87 if (IS_ERR(clk) || clk == NULL)
88 return -EINVAL;
89
90 clk_enable(clk->parent);
91
92 spin_lock(&clocks_lock);
93
94 if ((clk->usage++) == 0)
95 (clk->enable)(clk, 1);
96
97 spin_unlock(&clocks_lock);
98 return 0;
99}
100
101void clk_disable(struct clk *clk)
102{
103 if (IS_ERR(clk) || clk == NULL)
104 return;
105
106 spin_lock(&clocks_lock);
107
108 if ((--clk->usage) == 0)
109 (clk->enable)(clk, 0);
110
111 spin_unlock(&clocks_lock);
112 clk_disable(clk->parent);
113}
114
115
116unsigned long clk_get_rate(struct clk *clk)
117{
118 if (IS_ERR(clk))
119 return 0;
120
121 if (clk->rate != 0)
122 return clk->rate;
123
Ben Dooksb3bf41b2009-12-01 01:24:37 +0000124 if (clk->ops != NULL && clk->ops->get_rate != NULL)
125 return (clk->ops->get_rate)(clk);
Ben Dooksadbefaa2008-10-21 14:06:54 +0100126
127 if (clk->parent != NULL)
128 return clk_get_rate(clk->parent);
129
130 return clk->rate;
131}
132
133long clk_round_rate(struct clk *clk, unsigned long rate)
134{
Ben Dooksb3bf41b2009-12-01 01:24:37 +0000135 if (!IS_ERR(clk) && clk->ops && clk->ops->round_rate)
136 return (clk->ops->round_rate)(clk, rate);
Ben Dooksadbefaa2008-10-21 14:06:54 +0100137
138 return rate;
139}
140
141int clk_set_rate(struct clk *clk, unsigned long rate)
142{
143 int ret;
144
145 if (IS_ERR(clk))
146 return -EINVAL;
147
148 /* We do not default just do a clk->rate = rate as
149 * the clock may have been made this way by choice.
150 */
151
Ben Dooksb3bf41b2009-12-01 01:24:37 +0000152 WARN_ON(clk->ops == NULL);
153 WARN_ON(clk->ops && clk->ops->set_rate == NULL);
Ben Dooksadbefaa2008-10-21 14:06:54 +0100154
Ben Dooksb3bf41b2009-12-01 01:24:37 +0000155 if (clk->ops == NULL || clk->ops->set_rate == NULL)
Ben Dooksadbefaa2008-10-21 14:06:54 +0100156 return -EINVAL;
157
158 spin_lock(&clocks_lock);
Ben Dooksb3bf41b2009-12-01 01:24:37 +0000159 ret = (clk->ops->set_rate)(clk, rate);
Ben Dooksadbefaa2008-10-21 14:06:54 +0100160 spin_unlock(&clocks_lock);
161
162 return ret;
163}
164
165struct clk *clk_get_parent(struct clk *clk)
166{
167 return clk->parent;
168}
169
170int clk_set_parent(struct clk *clk, struct clk *parent)
171{
172 int ret = 0;
173
174 if (IS_ERR(clk))
175 return -EINVAL;
176
177 spin_lock(&clocks_lock);
178
Ben Dooksb3bf41b2009-12-01 01:24:37 +0000179 if (clk->ops && clk->ops->set_parent)
180 ret = (clk->ops->set_parent)(clk, parent);
Ben Dooksadbefaa2008-10-21 14:06:54 +0100181
182 spin_unlock(&clocks_lock);
183
184 return ret;
185}
186
Ben Dooksadbefaa2008-10-21 14:06:54 +0100187EXPORT_SYMBOL(clk_enable);
188EXPORT_SYMBOL(clk_disable);
189EXPORT_SYMBOL(clk_get_rate);
190EXPORT_SYMBOL(clk_round_rate);
191EXPORT_SYMBOL(clk_set_rate);
192EXPORT_SYMBOL(clk_get_parent);
193EXPORT_SYMBOL(clk_set_parent);
194
195/* base clocks */
196
Kukjin Kimed276842010-01-14 12:50:23 +0900197int clk_default_setrate(struct clk *clk, unsigned long rate)
Ben Dooksadbefaa2008-10-21 14:06:54 +0100198{
199 clk->rate = rate;
200 return 0;
201}
202
Kukjin Kimed276842010-01-14 12:50:23 +0900203struct clk_ops clk_ops_def_setrate = {
Ben Dooksb3bf41b2009-12-01 01:24:37 +0000204 .set_rate = clk_default_setrate,
205};
206
Ben Dooksadbefaa2008-10-21 14:06:54 +0100207struct clk clk_xtal = {
208 .name = "xtal",
Ben Dooksadbefaa2008-10-21 14:06:54 +0100209 .rate = 0,
210 .parent = NULL,
211 .ctrlbit = 0,
212};
213
Ben Dooks4b31d8b2008-10-21 14:07:00 +0100214struct clk clk_ext = {
215 .name = "ext",
Ben Dooks4b31d8b2008-10-21 14:07:00 +0100216};
217
218struct clk clk_epll = {
219 .name = "epll",
Ben Dooks4b31d8b2008-10-21 14:07:00 +0100220};
221
Ben Dooksadbefaa2008-10-21 14:06:54 +0100222struct clk clk_mpll = {
223 .name = "mpll",
Ben Dooksb3bf41b2009-12-01 01:24:37 +0000224 .ops = &clk_ops_def_setrate,
Ben Dooksadbefaa2008-10-21 14:06:54 +0100225};
226
227struct clk clk_upll = {
228 .name = "upll",
Ben Dooksadbefaa2008-10-21 14:06:54 +0100229 .parent = NULL,
230 .ctrlbit = 0,
231};
232
233struct clk clk_f = {
234 .name = "fclk",
Ben Dooksadbefaa2008-10-21 14:06:54 +0100235 .rate = 0,
236 .parent = &clk_mpll,
237 .ctrlbit = 0,
Ben Dooksadbefaa2008-10-21 14:06:54 +0100238};
239
240struct clk clk_h = {
241 .name = "hclk",
Ben Dooksadbefaa2008-10-21 14:06:54 +0100242 .rate = 0,
243 .parent = NULL,
244 .ctrlbit = 0,
Ben Dooksb3bf41b2009-12-01 01:24:37 +0000245 .ops = &clk_ops_def_setrate,
Ben Dooksadbefaa2008-10-21 14:06:54 +0100246};
247
248struct clk clk_p = {
249 .name = "pclk",
Ben Dooksadbefaa2008-10-21 14:06:54 +0100250 .rate = 0,
251 .parent = NULL,
252 .ctrlbit = 0,
Ben Dooksb3bf41b2009-12-01 01:24:37 +0000253 .ops = &clk_ops_def_setrate,
Ben Dooksadbefaa2008-10-21 14:06:54 +0100254};
255
256struct clk clk_usb_bus = {
257 .name = "usb-bus",
Ben Dooksadbefaa2008-10-21 14:06:54 +0100258 .rate = 0,
259 .parent = &clk_upll,
260};
261
262
Ben Dooksadbefaa2008-10-21 14:06:54 +0100263struct clk s3c24xx_uclk = {
264 .name = "uclk",
Ben Dooksadbefaa2008-10-21 14:06:54 +0100265};
266
267/* initialise the clock system */
268
Ben Dooks8428d472010-01-25 10:44:10 +0900269/**
270 * s3c24xx_register_clock() - register a clock
271 * @clk: The clock to register
272 *
273 * Add the specified clock to the list of clocks known by the system.
274 */
Ben Dooksadbefaa2008-10-21 14:06:54 +0100275int s3c24xx_register_clock(struct clk *clk)
276{
Ben Dooksadbefaa2008-10-21 14:06:54 +0100277 if (clk->enable == NULL)
278 clk->enable = clk_null_enable;
279
Thomas Abrahamf86c6662011-06-14 19:12:26 +0900280 /* fill up the clk_lookup structure and register it*/
281 clk->lookup.dev_id = clk->devname;
282 clk->lookup.con_id = clk->name;
283 clk->lookup.clk = clk;
284 clkdev_add(&clk->lookup);
Ben Dooksadbefaa2008-10-21 14:06:54 +0100285
286 return 0;
287}
288
Ben Dooks8428d472010-01-25 10:44:10 +0900289/**
290 * s3c24xx_register_clocks() - register an array of clock pointers
291 * @clks: Pointer to an array of struct clk pointers
292 * @nr_clks: The number of clocks in the @clks array.
293 *
294 * Call s3c24xx_register_clock() for all the clock pointers contained
295 * in the @clks list. Returns the number of failures.
296 */
Ben Dooksadbefaa2008-10-21 14:06:54 +0100297int s3c24xx_register_clocks(struct clk **clks, int nr_clks)
298{
299 int fails = 0;
300
301 for (; nr_clks > 0; nr_clks--, clks++) {
Ben Dooks50ee2d32010-01-25 10:46:51 +0900302 if (s3c24xx_register_clock(*clks) < 0) {
303 struct clk *clk = *clks;
304 printk(KERN_ERR "%s: failed to register %p: %s\n",
305 __func__, clk, clk->name);
Ben Dooksadbefaa2008-10-21 14:06:54 +0100306 fails++;
Ben Dooks50ee2d32010-01-25 10:46:51 +0900307 }
Ben Dooksadbefaa2008-10-21 14:06:54 +0100308 }
309
310 return fails;
311}
312
Ben Dooks1d9f13c2010-01-06 01:21:38 +0900313/**
314 * s3c_register_clocks() - register an array of clocks
315 * @clkp: Pointer to the first clock in the array.
316 * @nr_clks: Number of clocks to register.
317 *
318 * Call s3c24xx_register_clock() on the @clkp array given, printing an
319 * error if it fails to register the clock (unlikely).
320 */
Ben Dooksab5d97d2010-01-25 10:39:23 +0900321void __init s3c_register_clocks(struct clk *clkp, int nr_clks)
Ben Dooks1d9f13c2010-01-06 01:21:38 +0900322{
323 int ret;
324
325 for (; nr_clks > 0; nr_clks--, clkp++) {
326 ret = s3c24xx_register_clock(clkp);
327
328 if (ret < 0) {
329 printk(KERN_ERR "Failed to register clock %s (%d)\n",
330 clkp->name, ret);
331 }
332 }
333}
334
Ben Dooks4e046912010-04-28 12:58:13 +0900335/**
336 * s3c_disable_clocks() - disable an array of clocks
337 * @clkp: Pointer to the first clock in the array.
338 * @nr_clks: Number of clocks to register.
339 *
340 * for internal use only at initialisation time. disable the clocks in the
341 * @clkp array.
342 */
343
344void __init s3c_disable_clocks(struct clk *clkp, int nr_clks)
345{
346 for (; nr_clks > 0; nr_clks--, clkp++)
347 (clkp->enable)(clkp, 0);
348}
349
Uwe Kleine-König421f91d2010-06-11 12:17:00 +0200350/* initialise all the clocks */
Ben Dooksadbefaa2008-10-21 14:06:54 +0100351
352int __init s3c24xx_register_baseclocks(unsigned long xtal)
353{
Ben Dooks50f430e2009-11-13 22:54:12 +0000354 printk(KERN_INFO "S3C24XX Clocks, Copyright 2004 Simtec Electronics\n");
Ben Dooksadbefaa2008-10-21 14:06:54 +0100355
356 clk_xtal.rate = xtal;
357
358 /* register our clocks */
359
360 if (s3c24xx_register_clock(&clk_xtal) < 0)
361 printk(KERN_ERR "failed to register master xtal\n");
362
363 if (s3c24xx_register_clock(&clk_mpll) < 0)
364 printk(KERN_ERR "failed to register mpll clock\n");
365
366 if (s3c24xx_register_clock(&clk_upll) < 0)
367 printk(KERN_ERR "failed to register upll clock\n");
368
369 if (s3c24xx_register_clock(&clk_f) < 0)
370 printk(KERN_ERR "failed to register cpu fclk\n");
371
372 if (s3c24xx_register_clock(&clk_h) < 0)
373 printk(KERN_ERR "failed to register cpu hclk\n");
374
375 if (s3c24xx_register_clock(&clk_p) < 0)
376 printk(KERN_ERR "failed to register cpu pclk\n");
377
378 return 0;
379}
380
Amit Daniel Kachhap436c3872011-01-12 13:40:04 +0900381#if defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS)
382/* debugfs support to trace clock tree hierarchy and attributes */
383
384static struct dentry *clk_debugfs_root;
385
386static int clk_debugfs_register_one(struct clk *c)
387{
388 int err;
Al Viro12520c42011-07-16 12:37:57 -0400389 struct dentry *d;
Amit Daniel Kachhap436c3872011-01-12 13:40:04 +0900390 struct clk *pa = c->parent;
391 char s[255];
392 char *p = s;
393
Thomas Abrahamf86c6662011-06-14 19:12:26 +0900394 p += sprintf(p, "%s", c->devname);
Amit Daniel Kachhap436c3872011-01-12 13:40:04 +0900395
396 d = debugfs_create_dir(s, pa ? pa->dent : clk_debugfs_root);
397 if (!d)
398 return -ENOMEM;
399
400 c->dent = d;
401
402 d = debugfs_create_u8("usecount", S_IRUGO, c->dent, (u8 *)&c->usage);
403 if (!d) {
404 err = -ENOMEM;
405 goto err_out;
406 }
407
408 d = debugfs_create_u32("rate", S_IRUGO, c->dent, (u32 *)&c->rate);
409 if (!d) {
410 err = -ENOMEM;
411 goto err_out;
412 }
413 return 0;
414
415err_out:
Al Viro12520c42011-07-16 12:37:57 -0400416 debugfs_remove_recursive(c->dent);
Amit Daniel Kachhap436c3872011-01-12 13:40:04 +0900417 return err;
418}
419
420static int clk_debugfs_register(struct clk *c)
421{
422 int err;
423 struct clk *pa = c->parent;
424
425 if (pa && !pa->dent) {
426 err = clk_debugfs_register(pa);
427 if (err)
428 return err;
429 }
430
431 if (!c->dent) {
432 err = clk_debugfs_register_one(c);
433 if (err)
434 return err;
435 }
436 return 0;
437}
438
439static int __init clk_debugfs_init(void)
440{
441 struct clk *c;
442 struct dentry *d;
443 int err;
444
445 d = debugfs_create_dir("clock", NULL);
446 if (!d)
447 return -ENOMEM;
448 clk_debugfs_root = d;
449
450 list_for_each_entry(c, &clocks, list) {
451 err = clk_debugfs_register(c);
452 if (err)
453 goto err_out;
454 }
455 return 0;
456
457err_out:
458 debugfs_remove_recursive(clk_debugfs_root);
459 return err;
460}
461late_initcall(clk_debugfs_init);
462
463#endif /* defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS) */