diff options
Diffstat (limited to 'arch/arm/plat-samsung/clock.c')
-rw-r--r-- | arch/arm/plat-samsung/clock.c | 409 |
1 files changed, 409 insertions, 0 deletions
diff --git a/arch/arm/plat-samsung/clock.c b/arch/arm/plat-samsung/clock.c new file mode 100644 index 000000000000..1b25c9d8c403 --- /dev/null +++ b/arch/arm/plat-samsung/clock.c | |||
@@ -0,0 +1,409 @@ | |||
1 | /* linux/arch/arm/plat-s3c24xx/clock.c | ||
2 | * | ||
3 | * Copyright 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/spinlock.h> | ||
41 | #include <linux/io.h> | ||
42 | |||
43 | #include <mach/hardware.h> | ||
44 | #include <asm/irq.h> | ||
45 | |||
46 | #include <plat/cpu-freq.h> | ||
47 | |||
48 | #include <plat/clock.h> | ||
49 | #include <plat/cpu.h> | ||
50 | |||
51 | /* clock information */ | ||
52 | |||
53 | static LIST_HEAD(clocks); | ||
54 | |||
55 | /* We originally used an mutex here, but some contexts (see resume) | ||
56 | * are calling functions such as clk_set_parent() with IRQs disabled | ||
57 | * causing an BUG to be triggered. | ||
58 | */ | ||
59 | DEFINE_SPINLOCK(clocks_lock); | ||
60 | |||
61 | /* enable and disable calls for use with the clk struct */ | ||
62 | |||
63 | static int clk_null_enable(struct clk *clk, int enable) | ||
64 | { | ||
65 | return 0; | ||
66 | } | ||
67 | |||
68 | /* Clock API calls */ | ||
69 | |||
70 | struct clk *clk_get(struct device *dev, const char *id) | ||
71 | { | ||
72 | struct clk *p; | ||
73 | struct clk *clk = ERR_PTR(-ENOENT); | ||
74 | int idno; | ||
75 | |||
76 | if (dev == NULL || dev->bus != &platform_bus_type) | ||
77 | idno = -1; | ||
78 | else | ||
79 | idno = to_platform_device(dev)->id; | ||
80 | |||
81 | spin_lock(&clocks_lock); | ||
82 | |||
83 | list_for_each_entry(p, &clocks, list) { | ||
84 | if (p->id == idno && | ||
85 | strcmp(id, p->name) == 0 && | ||
86 | try_module_get(p->owner)) { | ||
87 | clk = p; | ||
88 | break; | ||
89 | } | ||
90 | } | ||
91 | |||
92 | /* check for the case where a device was supplied, but the | ||
93 | * clock that was being searched for is not device specific */ | ||
94 | |||
95 | if (IS_ERR(clk)) { | ||
96 | list_for_each_entry(p, &clocks, list) { | ||
97 | if (p->id == -1 && strcmp(id, p->name) == 0 && | ||
98 | try_module_get(p->owner)) { | ||
99 | clk = p; | ||
100 | break; | ||
101 | } | ||
102 | } | ||
103 | } | ||
104 | |||
105 | spin_unlock(&clocks_lock); | ||
106 | return clk; | ||
107 | } | ||
108 | |||
109 | void clk_put(struct clk *clk) | ||
110 | { | ||
111 | module_put(clk->owner); | ||
112 | } | ||
113 | |||
114 | int clk_enable(struct clk *clk) | ||
115 | { | ||
116 | if (IS_ERR(clk) || clk == NULL) | ||
117 | return -EINVAL; | ||
118 | |||
119 | clk_enable(clk->parent); | ||
120 | |||
121 | spin_lock(&clocks_lock); | ||
122 | |||
123 | if ((clk->usage++) == 0) | ||
124 | (clk->enable)(clk, 1); | ||
125 | |||
126 | spin_unlock(&clocks_lock); | ||
127 | return 0; | ||
128 | } | ||
129 | |||
130 | void clk_disable(struct clk *clk) | ||
131 | { | ||
132 | if (IS_ERR(clk) || clk == NULL) | ||
133 | return; | ||
134 | |||
135 | spin_lock(&clocks_lock); | ||
136 | |||
137 | if ((--clk->usage) == 0) | ||
138 | (clk->enable)(clk, 0); | ||
139 | |||
140 | spin_unlock(&clocks_lock); | ||
141 | clk_disable(clk->parent); | ||
142 | } | ||
143 | |||
144 | |||
145 | unsigned long clk_get_rate(struct clk *clk) | ||
146 | { | ||
147 | if (IS_ERR(clk)) | ||
148 | return 0; | ||
149 | |||
150 | if (clk->rate != 0) | ||
151 | return clk->rate; | ||
152 | |||
153 | if (clk->ops != NULL && clk->ops->get_rate != NULL) | ||
154 | return (clk->ops->get_rate)(clk); | ||
155 | |||
156 | if (clk->parent != NULL) | ||
157 | return clk_get_rate(clk->parent); | ||
158 | |||
159 | return clk->rate; | ||
160 | } | ||
161 | |||
162 | long clk_round_rate(struct clk *clk, unsigned long rate) | ||
163 | { | ||
164 | if (!IS_ERR(clk) && clk->ops && clk->ops->round_rate) | ||
165 | return (clk->ops->round_rate)(clk, rate); | ||
166 | |||
167 | return rate; | ||
168 | } | ||
169 | |||
170 | int clk_set_rate(struct clk *clk, unsigned long rate) | ||
171 | { | ||
172 | int ret; | ||
173 | |||
174 | if (IS_ERR(clk)) | ||
175 | return -EINVAL; | ||
176 | |||
177 | /* We do not default just do a clk->rate = rate as | ||
178 | * the clock may have been made this way by choice. | ||
179 | */ | ||
180 | |||
181 | WARN_ON(clk->ops == NULL); | ||
182 | WARN_ON(clk->ops && clk->ops->set_rate == NULL); | ||
183 | |||
184 | if (clk->ops == NULL || clk->ops->set_rate == NULL) | ||
185 | return -EINVAL; | ||
186 | |||
187 | spin_lock(&clocks_lock); | ||
188 | ret = (clk->ops->set_rate)(clk, rate); | ||
189 | spin_unlock(&clocks_lock); | ||
190 | |||
191 | return ret; | ||
192 | } | ||
193 | |||
194 | struct clk *clk_get_parent(struct clk *clk) | ||
195 | { | ||
196 | return clk->parent; | ||
197 | } | ||
198 | |||
199 | int clk_set_parent(struct clk *clk, struct clk *parent) | ||
200 | { | ||
201 | int ret = 0; | ||
202 | |||
203 | if (IS_ERR(clk)) | ||
204 | return -EINVAL; | ||
205 | |||
206 | spin_lock(&clocks_lock); | ||
207 | |||
208 | if (clk->ops && clk->ops->set_parent) | ||
209 | ret = (clk->ops->set_parent)(clk, parent); | ||
210 | |||
211 | spin_unlock(&clocks_lock); | ||
212 | |||
213 | return ret; | ||
214 | } | ||
215 | |||
216 | EXPORT_SYMBOL(clk_get); | ||
217 | EXPORT_SYMBOL(clk_put); | ||
218 | EXPORT_SYMBOL(clk_enable); | ||
219 | EXPORT_SYMBOL(clk_disable); | ||
220 | EXPORT_SYMBOL(clk_get_rate); | ||
221 | EXPORT_SYMBOL(clk_round_rate); | ||
222 | EXPORT_SYMBOL(clk_set_rate); | ||
223 | EXPORT_SYMBOL(clk_get_parent); | ||
224 | EXPORT_SYMBOL(clk_set_parent); | ||
225 | |||
226 | /* base clocks */ | ||
227 | |||
228 | int clk_default_setrate(struct clk *clk, unsigned long rate) | ||
229 | { | ||
230 | clk->rate = rate; | ||
231 | return 0; | ||
232 | } | ||
233 | |||
234 | struct clk_ops clk_ops_def_setrate = { | ||
235 | .set_rate = clk_default_setrate, | ||
236 | }; | ||
237 | |||
238 | struct clk clk_xtal = { | ||
239 | .name = "xtal", | ||
240 | .id = -1, | ||
241 | .rate = 0, | ||
242 | .parent = NULL, | ||
243 | .ctrlbit = 0, | ||
244 | }; | ||
245 | |||
246 | struct clk clk_ext = { | ||
247 | .name = "ext", | ||
248 | .id = -1, | ||
249 | }; | ||
250 | |||
251 | struct clk clk_epll = { | ||
252 | .name = "epll", | ||
253 | .id = -1, | ||
254 | }; | ||
255 | |||
256 | struct clk clk_mpll = { | ||
257 | .name = "mpll", | ||
258 | .id = -1, | ||
259 | .ops = &clk_ops_def_setrate, | ||
260 | }; | ||
261 | |||
262 | struct clk clk_upll = { | ||
263 | .name = "upll", | ||
264 | .id = -1, | ||
265 | .parent = NULL, | ||
266 | .ctrlbit = 0, | ||
267 | }; | ||
268 | |||
269 | struct clk clk_f = { | ||
270 | .name = "fclk", | ||
271 | .id = -1, | ||
272 | .rate = 0, | ||
273 | .parent = &clk_mpll, | ||
274 | .ctrlbit = 0, | ||
275 | }; | ||
276 | |||
277 | struct clk clk_h = { | ||
278 | .name = "hclk", | ||
279 | .id = -1, | ||
280 | .rate = 0, | ||
281 | .parent = NULL, | ||
282 | .ctrlbit = 0, | ||
283 | .ops = &clk_ops_def_setrate, | ||
284 | }; | ||
285 | |||
286 | struct clk clk_p = { | ||
287 | .name = "pclk", | ||
288 | .id = -1, | ||
289 | .rate = 0, | ||
290 | .parent = NULL, | ||
291 | .ctrlbit = 0, | ||
292 | .ops = &clk_ops_def_setrate, | ||
293 | }; | ||
294 | |||
295 | struct clk clk_usb_bus = { | ||
296 | .name = "usb-bus", | ||
297 | .id = -1, | ||
298 | .rate = 0, | ||
299 | .parent = &clk_upll, | ||
300 | }; | ||
301 | |||
302 | |||
303 | struct clk s3c24xx_uclk = { | ||
304 | .name = "uclk", | ||
305 | .id = -1, | ||
306 | }; | ||
307 | |||
308 | /* initialise the clock system */ | ||
309 | |||
310 | /** | ||
311 | * s3c24xx_register_clock() - register a clock | ||
312 | * @clk: The clock to register | ||
313 | * | ||
314 | * Add the specified clock to the list of clocks known by the system. | ||
315 | */ | ||
316 | int s3c24xx_register_clock(struct clk *clk) | ||
317 | { | ||
318 | if (clk->enable == NULL) | ||
319 | clk->enable = clk_null_enable; | ||
320 | |||
321 | /* add to the list of available clocks */ | ||
322 | |||
323 | /* Quick check to see if this clock has already been registered. */ | ||
324 | BUG_ON(clk->list.prev != clk->list.next); | ||
325 | |||
326 | spin_lock(&clocks_lock); | ||
327 | list_add(&clk->list, &clocks); | ||
328 | spin_unlock(&clocks_lock); | ||
329 | |||
330 | return 0; | ||
331 | } | ||
332 | |||
333 | /** | ||
334 | * s3c24xx_register_clocks() - register an array of clock pointers | ||
335 | * @clks: Pointer to an array of struct clk pointers | ||
336 | * @nr_clks: The number of clocks in the @clks array. | ||
337 | * | ||
338 | * Call s3c24xx_register_clock() for all the clock pointers contained | ||
339 | * in the @clks list. Returns the number of failures. | ||
340 | */ | ||
341 | int s3c24xx_register_clocks(struct clk **clks, int nr_clks) | ||
342 | { | ||
343 | int fails = 0; | ||
344 | |||
345 | for (; nr_clks > 0; nr_clks--, clks++) { | ||
346 | if (s3c24xx_register_clock(*clks) < 0) { | ||
347 | struct clk *clk = *clks; | ||
348 | printk(KERN_ERR "%s: failed to register %p: %s\n", | ||
349 | __func__, clk, clk->name); | ||
350 | fails++; | ||
351 | } | ||
352 | } | ||
353 | |||
354 | return fails; | ||
355 | } | ||
356 | |||
357 | /** | ||
358 | * s3c_register_clocks() - register an array of clocks | ||
359 | * @clkp: Pointer to the first clock in the array. | ||
360 | * @nr_clks: Number of clocks to register. | ||
361 | * | ||
362 | * Call s3c24xx_register_clock() on the @clkp array given, printing an | ||
363 | * error if it fails to register the clock (unlikely). | ||
364 | */ | ||
365 | void __init s3c_register_clocks(struct clk *clkp, int nr_clks) | ||
366 | { | ||
367 | int ret; | ||
368 | |||
369 | for (; nr_clks > 0; nr_clks--, clkp++) { | ||
370 | ret = s3c24xx_register_clock(clkp); | ||
371 | |||
372 | if (ret < 0) { | ||
373 | printk(KERN_ERR "Failed to register clock %s (%d)\n", | ||
374 | clkp->name, ret); | ||
375 | } | ||
376 | } | ||
377 | } | ||
378 | |||
379 | /* initalise all the clocks */ | ||
380 | |||
381 | int __init s3c24xx_register_baseclocks(unsigned long xtal) | ||
382 | { | ||
383 | printk(KERN_INFO "S3C24XX Clocks, Copyright 2004 Simtec Electronics\n"); | ||
384 | |||
385 | clk_xtal.rate = xtal; | ||
386 | |||
387 | /* register our clocks */ | ||
388 | |||
389 | if (s3c24xx_register_clock(&clk_xtal) < 0) | ||
390 | printk(KERN_ERR "failed to register master xtal\n"); | ||
391 | |||
392 | if (s3c24xx_register_clock(&clk_mpll) < 0) | ||
393 | printk(KERN_ERR "failed to register mpll clock\n"); | ||
394 | |||
395 | if (s3c24xx_register_clock(&clk_upll) < 0) | ||
396 | printk(KERN_ERR "failed to register upll clock\n"); | ||
397 | |||
398 | if (s3c24xx_register_clock(&clk_f) < 0) | ||
399 | printk(KERN_ERR "failed to register cpu fclk\n"); | ||
400 | |||
401 | if (s3c24xx_register_clock(&clk_h) < 0) | ||
402 | printk(KERN_ERR "failed to register cpu hclk\n"); | ||
403 | |||
404 | if (s3c24xx_register_clock(&clk_p) < 0) | ||
405 | printk(KERN_ERR "failed to register cpu pclk\n"); | ||
406 | |||
407 | return 0; | ||
408 | } | ||
409 | |||