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-rw-r--r--arch/arm/plat-s3c24xx/clock.c449
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diff --git a/arch/arm/plat-s3c24xx/clock.c b/arch/arm/plat-s3c24xx/clock.c
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1/* linux/arch/arm/plat-s3c24xx/clock.c
2 *
3 * Copyright (c) 2004-2005 Simtec Electronics
4 * 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>
36#include <linux/sysdev.h>
37#include <linux/interrupt.h>
38#include <linux/ioport.h>
39#include <linux/clk.h>
40#include <linux/mutex.h>
41#include <linux/delay.h>
42
43#include <asm/hardware.h>
44#include <asm/irq.h>
45#include <asm/io.h>
46
47#include <asm/arch/regs-clock.h>
48#include <asm/arch/regs-gpio.h>
49
50#include <asm/plat-s3c24xx/clock.h>
51#include <asm/plat-s3c24xx/cpu.h>
52
53/* clock information */
54
55static LIST_HEAD(clocks);
56
57DEFINE_MUTEX(clocks_mutex);
58
59/* enable and disable calls for use with the clk struct */
60
61static int clk_null_enable(struct clk *clk, int enable)
62{
63 return 0;
64}
65
66/* Clock API calls */
67
68struct clk *clk_get(struct device *dev, const char *id)
69{
70 struct clk *p;
71 struct clk *clk = ERR_PTR(-ENOENT);
72 int idno;
73
74 if (dev == NULL || dev->bus != &platform_bus_type)
75 idno = -1;
76 else
77 idno = to_platform_device(dev)->id;
78
79 mutex_lock(&clocks_mutex);
80
81 list_for_each_entry(p, &clocks, list) {
82 if (p->id == idno &&
83 strcmp(id, p->name) == 0 &&
84 try_module_get(p->owner)) {
85 clk = p;
86 break;
87 }
88 }
89
90 /* check for the case where a device was supplied, but the
91 * clock that was being searched for is not device specific */
92
93 if (IS_ERR(clk)) {
94 list_for_each_entry(p, &clocks, list) {
95 if (p->id == -1 && strcmp(id, p->name) == 0 &&
96 try_module_get(p->owner)) {
97 clk = p;
98 break;
99 }
100 }
101 }
102
103 mutex_unlock(&clocks_mutex);
104 return clk;
105}
106
107void clk_put(struct clk *clk)
108{
109 module_put(clk->owner);
110}
111
112int clk_enable(struct clk *clk)
113{
114 if (IS_ERR(clk) || clk == NULL)
115 return -EINVAL;
116
117 clk_enable(clk->parent);
118
119 mutex_lock(&clocks_mutex);
120
121 if ((clk->usage++) == 0)
122 (clk->enable)(clk, 1);
123
124 mutex_unlock(&clocks_mutex);
125 return 0;
126}
127
128void clk_disable(struct clk *clk)
129{
130 if (IS_ERR(clk) || clk == NULL)
131 return;
132
133 mutex_lock(&clocks_mutex);
134
135 if ((--clk->usage) == 0)
136 (clk->enable)(clk, 0);
137
138 mutex_unlock(&clocks_mutex);
139 clk_disable(clk->parent);
140}
141
142
143unsigned long clk_get_rate(struct clk *clk)
144{
145 if (IS_ERR(clk))
146 return 0;
147
148 if (clk->rate != 0)
149 return clk->rate;
150
151 if (clk->get_rate != NULL)
152 return (clk->get_rate)(clk);
153
154 if (clk->parent != NULL)
155 return clk_get_rate(clk->parent);
156
157 return clk->rate;
158}
159
160long clk_round_rate(struct clk *clk, unsigned long rate)
161{
162 if (!IS_ERR(clk) && clk->round_rate)
163 return (clk->round_rate)(clk, rate);
164
165 return rate;
166}
167
168int clk_set_rate(struct clk *clk, unsigned long rate)
169{
170 int ret;
171
172 if (IS_ERR(clk))
173 return -EINVAL;
174
175 mutex_lock(&clocks_mutex);
176 ret = (clk->set_rate)(clk, rate);
177 mutex_unlock(&clocks_mutex);
178
179 return ret;
180}
181
182struct clk *clk_get_parent(struct clk *clk)
183{
184 return clk->parent;
185}
186
187int clk_set_parent(struct clk *clk, struct clk *parent)
188{
189 int ret = 0;
190
191 if (IS_ERR(clk))
192 return -EINVAL;
193
194 mutex_lock(&clocks_mutex);
195
196 if (clk->set_parent)
197 ret = (clk->set_parent)(clk, parent);
198
199 mutex_unlock(&clocks_mutex);
200
201 return ret;
202}
203
204EXPORT_SYMBOL(clk_get);
205EXPORT_SYMBOL(clk_put);
206EXPORT_SYMBOL(clk_enable);
207EXPORT_SYMBOL(clk_disable);
208EXPORT_SYMBOL(clk_get_rate);
209EXPORT_SYMBOL(clk_round_rate);
210EXPORT_SYMBOL(clk_set_rate);
211EXPORT_SYMBOL(clk_get_parent);
212EXPORT_SYMBOL(clk_set_parent);
213
214/* base clocks */
215
216struct clk clk_xtal = {
217 .name = "xtal",
218 .id = -1,
219 .rate = 0,
220 .parent = NULL,
221 .ctrlbit = 0,
222};
223
224struct clk clk_mpll = {
225 .name = "mpll",
226 .id = -1,
227};
228
229struct clk clk_upll = {
230 .name = "upll",
231 .id = -1,
232 .parent = NULL,
233 .ctrlbit = 0,
234};
235
236struct clk clk_f = {
237 .name = "fclk",
238 .id = -1,
239 .rate = 0,
240 .parent = &clk_mpll,
241 .ctrlbit = 0,
242};
243
244struct clk clk_h = {
245 .name = "hclk",
246 .id = -1,
247 .rate = 0,
248 .parent = NULL,
249 .ctrlbit = 0,
250};
251
252struct clk clk_p = {
253 .name = "pclk",
254 .id = -1,
255 .rate = 0,
256 .parent = NULL,
257 .ctrlbit = 0,
258};
259
260struct clk clk_usb_bus = {
261 .name = "usb-bus",
262 .id = -1,
263 .rate = 0,
264 .parent = &clk_upll,
265};
266
267/* clocks that could be registered by external code */
268
269static int s3c24xx_dclk_enable(struct clk *clk, int enable)
270{
271 unsigned long dclkcon = __raw_readl(S3C24XX_DCLKCON);
272
273 if (enable)
274 dclkcon |= clk->ctrlbit;
275 else
276 dclkcon &= ~clk->ctrlbit;
277
278 __raw_writel(dclkcon, S3C24XX_DCLKCON);
279
280 return 0;
281}
282
283static int s3c24xx_dclk_setparent(struct clk *clk, struct clk *parent)
284{
285 unsigned long dclkcon;
286 unsigned int uclk;
287
288 if (parent == &clk_upll)
289 uclk = 1;
290 else if (parent == &clk_p)
291 uclk = 0;
292 else
293 return -EINVAL;
294
295 clk->parent = parent;
296
297 dclkcon = __raw_readl(S3C24XX_DCLKCON);
298
299 if (clk->ctrlbit == S3C2410_DCLKCON_DCLK0EN) {
300 if (uclk)
301 dclkcon |= S3C2410_DCLKCON_DCLK0_UCLK;
302 else
303 dclkcon &= ~S3C2410_DCLKCON_DCLK0_UCLK;
304 } else {
305 if (uclk)
306 dclkcon |= S3C2410_DCLKCON_DCLK1_UCLK;
307 else
308 dclkcon &= ~S3C2410_DCLKCON_DCLK1_UCLK;
309 }
310
311 __raw_writel(dclkcon, S3C24XX_DCLKCON);
312
313 return 0;
314}
315
316
317static int s3c24xx_clkout_setparent(struct clk *clk, struct clk *parent)
318{
319 unsigned long mask;
320 unsigned long source;
321
322 /* calculate the MISCCR setting for the clock */
323
324 if (parent == &clk_xtal)
325 source = S3C2410_MISCCR_CLK0_MPLL;
326 else if (parent == &clk_upll)
327 source = S3C2410_MISCCR_CLK0_UPLL;
328 else if (parent == &clk_f)
329 source = S3C2410_MISCCR_CLK0_FCLK;
330 else if (parent == &clk_h)
331 source = S3C2410_MISCCR_CLK0_HCLK;
332 else if (parent == &clk_p)
333 source = S3C2410_MISCCR_CLK0_PCLK;
334 else if (clk == &s3c24xx_clkout0 && parent == &s3c24xx_dclk0)
335 source = S3C2410_MISCCR_CLK0_DCLK0;
336 else if (clk == &s3c24xx_clkout1 && parent == &s3c24xx_dclk1)
337 source = S3C2410_MISCCR_CLK0_DCLK0;
338 else
339 return -EINVAL;
340
341 clk->parent = parent;
342
343 if (clk == &s3c24xx_dclk0)
344 mask = S3C2410_MISCCR_CLK0_MASK;
345 else {
346 source <<= 4;
347 mask = S3C2410_MISCCR_CLK1_MASK;
348 }
349
350 s3c2410_modify_misccr(mask, source);
351 return 0;
352}
353
354/* external clock definitions */
355
356struct clk s3c24xx_dclk0 = {
357 .name = "dclk0",
358 .id = -1,
359 .ctrlbit = S3C2410_DCLKCON_DCLK0EN,
360 .enable = s3c24xx_dclk_enable,
361 .set_parent = s3c24xx_dclk_setparent,
362};
363
364struct clk s3c24xx_dclk1 = {
365 .name = "dclk1",
366 .id = -1,
367 .ctrlbit = S3C2410_DCLKCON_DCLK0EN,
368 .enable = s3c24xx_dclk_enable,
369 .set_parent = s3c24xx_dclk_setparent,
370};
371
372struct clk s3c24xx_clkout0 = {
373 .name = "clkout0",
374 .id = -1,
375 .set_parent = s3c24xx_clkout_setparent,
376};
377
378struct clk s3c24xx_clkout1 = {
379 .name = "clkout1",
380 .id = -1,
381 .set_parent = s3c24xx_clkout_setparent,
382};
383
384struct clk s3c24xx_uclk = {
385 .name = "uclk",
386 .id = -1,
387};
388
389/* initialise the clock system */
390
391int s3c24xx_register_clock(struct clk *clk)
392{
393 clk->owner = THIS_MODULE;
394
395 if (clk->enable == NULL)
396 clk->enable = clk_null_enable;
397
398 /* add to the list of available clocks */
399
400 mutex_lock(&clocks_mutex);
401 list_add(&clk->list, &clocks);
402 mutex_unlock(&clocks_mutex);
403
404 return 0;
405}
406
407/* initalise all the clocks */
408
409int __init s3c24xx_setup_clocks(unsigned long xtal,
410 unsigned long fclk,
411 unsigned long hclk,
412 unsigned long pclk)
413{
414 printk(KERN_INFO "S3C24XX Clocks, (c) 2004 Simtec Electronics\n");
415
416 /* initialise the main system clocks */
417
418 clk_xtal.rate = xtal;
419 clk_upll.rate = s3c2410_get_pll(__raw_readl(S3C2410_UPLLCON), xtal);
420
421 clk_mpll.rate = fclk;
422 clk_h.rate = hclk;
423 clk_p.rate = pclk;
424 clk_f.rate = fclk;
425
426 /* assume uart clocks are correctly setup */
427
428 /* register our clocks */
429
430 if (s3c24xx_register_clock(&clk_xtal) < 0)
431 printk(KERN_ERR "failed to register master xtal\n");
432
433 if (s3c24xx_register_clock(&clk_mpll) < 0)
434 printk(KERN_ERR "failed to register mpll clock\n");
435
436 if (s3c24xx_register_clock(&clk_upll) < 0)
437 printk(KERN_ERR "failed to register upll clock\n");
438
439 if (s3c24xx_register_clock(&clk_f) < 0)
440 printk(KERN_ERR "failed to register cpu fclk\n");
441
442 if (s3c24xx_register_clock(&clk_h) < 0)
443 printk(KERN_ERR "failed to register cpu hclk\n");
444
445 if (s3c24xx_register_clock(&clk_p) < 0)
446 printk(KERN_ERR "failed to register cpu pclk\n");
447
448 return 0;
449}