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-rw-r--r--arch/arm/mach-s3c2410/clock.c565
1 files changed, 196 insertions, 369 deletions
diff --git a/arch/arm/mach-s3c2410/clock.c b/arch/arm/mach-s3c2410/clock.c
index e13fb6778890..5b4831c4c1d8 100644
--- a/arch/arm/mach-s3c2410/clock.c
+++ b/arch/arm/mach-s3c2410/clock.c
@@ -1,15 +1,9 @@
1/* linux/arch/arm/mach-s3c2410/clock.c 1/* linux/arch/arm/mach-s3c2410/clock.c
2 * 2 *
3 * Copyright (c) 2004-2005 Simtec Electronics 3 * Copyright (c) 2006 Simtec Electronics
4 * Ben Dooks <ben@simtec.co.uk> 4 * Ben Dooks <ben@simtec.co.uk>
5 * 5 *
6 * S3C24XX Core clock control support 6 * S3C2410,S3C2440,S3C2442 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 * 7 *
14 * This program is free software; you can redistribute it and/or modify 8 * 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 9 * it under the terms of the GNU General Public License as published by
@@ -32,418 +26,251 @@
32#include <linux/list.h> 26#include <linux/list.h>
33#include <linux/errno.h> 27#include <linux/errno.h>
34#include <linux/err.h> 28#include <linux/err.h>
35#include <linux/platform_device.h>
36#include <linux/sysdev.h> 29#include <linux/sysdev.h>
37#include <linux/interrupt.h>
38#include <linux/ioport.h>
39#include <linux/clk.h> 30#include <linux/clk.h>
40#include <linux/mutex.h> 31#include <linux/mutex.h>
41#include <linux/delay.h> 32#include <linux/delay.h>
33#include <linux/serial_core.h>
34
35#include <asm/mach/map.h>
42 36
43#include <asm/hardware.h> 37#include <asm/hardware.h>
44#include <asm/irq.h>
45#include <asm/io.h> 38#include <asm/io.h>
46 39
40#include <asm/arch/regs-serial.h>
47#include <asm/arch/regs-clock.h> 41#include <asm/arch/regs-clock.h>
48#include <asm/arch/regs-gpio.h> 42#include <asm/arch/regs-gpio.h>
49 43
50#include "clock.h" 44#include <asm/plat-s3c24xx/s3c2410.h>
51#include "cpu.h" 45#include <asm/plat-s3c24xx/clock.h>
52 46#include <asm/plat-s3c24xx/cpu.h>
53/* clock information */
54 47
55static LIST_HEAD(clocks); 48int s3c2410_clkcon_enable(struct clk *clk, int enable)
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{ 49{
63 return 0; 50 unsigned int clocks = clk->ctrlbit;
64} 51 unsigned long clkcon;
65
66/* Clock API calls */
67 52
68struct clk *clk_get(struct device *dev, const char *id) 53 clkcon = __raw_readl(S3C2410_CLKCON);
69{
70 struct clk *p;
71 struct clk *clk = ERR_PTR(-ENOENT);
72 int idno;
73 54
74 if (dev == NULL || dev->bus != &platform_bus_type) 55 if (enable)
75 idno = -1; 56 clkcon |= clocks;
76 else 57 else
77 idno = to_platform_device(dev)->id; 58 clkcon &= ~clocks;
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 59
103 mutex_unlock(&clocks_mutex); 60 /* ensure none of the special function bits set */
104 return clk; 61 clkcon &= ~(S3C2410_CLKCON_IDLE|S3C2410_CLKCON_POWER);
105}
106 62
107void clk_put(struct clk *clk) 63 __raw_writel(clkcon, S3C2410_CLKCON);
108{
109 module_put(clk->owner);
110}
111 64
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; 65 return 0;
126} 66}
127 67
128void clk_disable(struct clk *clk) 68static int s3c2410_upll_enable(struct clk *clk, int enable)
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{ 69{
184 return clk->parent; 70 unsigned long clkslow = __raw_readl(S3C2410_CLKSLOW);
185} 71 unsigned long orig = clkslow;
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 72
273 if (enable) 73 if (enable)
274 dclkcon |= clk->ctrlbit; 74 clkslow &= ~S3C2410_CLKSLOW_UCLK_OFF;
275 else 75 else
276 dclkcon &= ~clk->ctrlbit; 76 clkslow |= S3C2410_CLKSLOW_UCLK_OFF;
277 77
278 __raw_writel(dclkcon, S3C24XX_DCLKCON); 78 __raw_writel(clkslow, S3C2410_CLKSLOW);
279 79
280 return 0; 80 /* if we started the UPLL, then allow to settle */
281}
282 81
283static int s3c24xx_dclk_setparent(struct clk *clk, struct clk *parent) 82 if (enable && (orig & S3C2410_CLKSLOW_UCLK_OFF))
284{ 83 udelay(200);
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 84
313 return 0; 85 return 0;
314} 86}
315 87
316 88/* standard clock definitions */
317static int s3c24xx_clkout_setparent(struct clk *clk, struct clk *parent) 89
318{ 90static struct clk init_clocks_disable[] = {
319 unsigned long mask; 91 {
320 unsigned long source; 92 .name = "nand",
321 93 .id = -1,
322 /* calculate the MISCCR setting for the clock */ 94 .parent = &clk_h,
323 95 .enable = s3c2410_clkcon_enable,
324 if (parent == &clk_xtal) 96 .ctrlbit = S3C2410_CLKCON_NAND,
325 source = S3C2410_MISCCR_CLK0_MPLL; 97 }, {
326 else if (parent == &clk_upll) 98 .name = "sdi",
327 source = S3C2410_MISCCR_CLK0_UPLL; 99 .id = -1,
328 else if (parent == &clk_f) 100 .parent = &clk_p,
329 source = S3C2410_MISCCR_CLK0_FCLK; 101 .enable = s3c2410_clkcon_enable,
330 else if (parent == &clk_h) 102 .ctrlbit = S3C2410_CLKCON_SDI,
331 source = S3C2410_MISCCR_CLK0_HCLK; 103 }, {
332 else if (parent == &clk_p) 104 .name = "adc",
333 source = S3C2410_MISCCR_CLK0_PCLK; 105 .id = -1,
334 else if (clk == &s3c24xx_clkout0 && parent == &s3c24xx_dclk0) 106 .parent = &clk_p,
335 source = S3C2410_MISCCR_CLK0_DCLK0; 107 .enable = s3c2410_clkcon_enable,
336 else if (clk == &s3c24xx_clkout1 && parent == &s3c24xx_dclk1) 108 .ctrlbit = S3C2410_CLKCON_ADC,
337 source = S3C2410_MISCCR_CLK0_DCLK0; 109 }, {
338 else 110 .name = "i2c",
339 return -EINVAL; 111 .id = -1,
340 112 .parent = &clk_p,
341 clk->parent = parent; 113 .enable = s3c2410_clkcon_enable,
342 114 .ctrlbit = S3C2410_CLKCON_IIC,
343 if (clk == &s3c24xx_dclk0) 115 }, {
344 mask = S3C2410_MISCCR_CLK0_MASK; 116 .name = "iis",
345 else { 117 .id = -1,
346 source <<= 4; 118 .parent = &clk_p,
347 mask = S3C2410_MISCCR_CLK1_MASK; 119 .enable = s3c2410_clkcon_enable,
120 .ctrlbit = S3C2410_CLKCON_IIS,
121 }, {
122 .name = "spi",
123 .id = -1,
124 .parent = &clk_p,
125 .enable = s3c2410_clkcon_enable,
126 .ctrlbit = S3C2410_CLKCON_SPI,
348 } 127 }
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}; 128};
371 129
372struct clk s3c24xx_clkout0 = { 130static struct clk init_clocks[] = {
373 .name = "clkout0", 131 {
374 .id = -1, 132 .name = "lcd",
375 .set_parent = s3c24xx_clkout_setparent, 133 .id = -1,
134 .parent = &clk_h,
135 .enable = s3c2410_clkcon_enable,
136 .ctrlbit = S3C2410_CLKCON_LCDC,
137 }, {
138 .name = "gpio",
139 .id = -1,
140 .parent = &clk_p,
141 .enable = s3c2410_clkcon_enable,
142 .ctrlbit = S3C2410_CLKCON_GPIO,
143 }, {
144 .name = "usb-host",
145 .id = -1,
146 .parent = &clk_h,
147 .enable = s3c2410_clkcon_enable,
148 .ctrlbit = S3C2410_CLKCON_USBH,
149 }, {
150 .name = "usb-device",
151 .id = -1,
152 .parent = &clk_h,
153 .enable = s3c2410_clkcon_enable,
154 .ctrlbit = S3C2410_CLKCON_USBD,
155 }, {
156 .name = "timers",
157 .id = -1,
158 .parent = &clk_p,
159 .enable = s3c2410_clkcon_enable,
160 .ctrlbit = S3C2410_CLKCON_PWMT,
161 }, {
162 .name = "uart",
163 .id = 0,
164 .parent = &clk_p,
165 .enable = s3c2410_clkcon_enable,
166 .ctrlbit = S3C2410_CLKCON_UART0,
167 }, {
168 .name = "uart",
169 .id = 1,
170 .parent = &clk_p,
171 .enable = s3c2410_clkcon_enable,
172 .ctrlbit = S3C2410_CLKCON_UART1,
173 }, {
174 .name = "uart",
175 .id = 2,
176 .parent = &clk_p,
177 .enable = s3c2410_clkcon_enable,
178 .ctrlbit = S3C2410_CLKCON_UART2,
179 }, {
180 .name = "rtc",
181 .id = -1,
182 .parent = &clk_p,
183 .enable = s3c2410_clkcon_enable,
184 .ctrlbit = S3C2410_CLKCON_RTC,
185 }, {
186 .name = "watchdog",
187 .id = -1,
188 .parent = &clk_p,
189 .ctrlbit = 0,
190 }, {
191 .name = "usb-bus-host",
192 .id = -1,
193 .parent = &clk_usb_bus,
194 }, {
195 .name = "usb-bus-gadget",
196 .id = -1,
197 .parent = &clk_usb_bus,
198 },
376}; 199};
377 200
378struct clk s3c24xx_clkout1 = { 201/* s3c2410_baseclk_add()
379 .name = "clkout1", 202 *
380 .id = -1, 203 * Add all the clocks used by the s3c2410 or compatible CPUs
381 .set_parent = s3c24xx_clkout_setparent, 204 * such as the S3C2440 and S3C2442.
382}; 205 *
383 206 * We cannot use a system device as we are needed before any
384struct clk s3c24xx_uclk = { 207 * of the init-calls that initialise the devices are actually
385 .name = "uclk", 208 * done.
386 .id = -1, 209*/
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 */
408 210
409int __init s3c24xx_setup_clocks(unsigned long xtal, 211int __init s3c2410_baseclk_add(void)
410 unsigned long fclk,
411 unsigned long hclk,
412 unsigned long pclk)
413{ 212{
414 printk(KERN_INFO "S3C24XX Clocks, (c) 2004 Simtec Electronics\n"); 213 unsigned long clkslow = __raw_readl(S3C2410_CLKSLOW);
214 unsigned long clkcon = __raw_readl(S3C2410_CLKCON);
215 struct clk *clkp;
216 struct clk *xtal;
217 int ret;
218 int ptr;
415 219
416 /* initialise the main system clocks */ 220 clk_upll.enable = s3c2410_upll_enable;
417 221
418 clk_xtal.rate = xtal; 222 if (s3c24xx_register_clock(&clk_usb_bus) < 0)
419 clk_upll.rate = s3c2410_get_pll(__raw_readl(S3C2410_UPLLCON), xtal); 223 printk(KERN_ERR "failed to register usb bus clock\n");
420 224
421 clk_mpll.rate = fclk; 225 /* register clocks from clock array */
422 clk_h.rate = hclk;
423 clk_p.rate = pclk;
424 clk_f.rate = fclk;
425 226
426 /* assume uart clocks are correctly setup */ 227 clkp = init_clocks;
228 for (ptr = 0; ptr < ARRAY_SIZE(init_clocks); ptr++, clkp++) {
229 /* ensure that we note the clock state */
427 230
428 /* register our clocks */ 231 clkp->usage = clkcon & clkp->ctrlbit ? 1 : 0;
429 232
430 if (s3c24xx_register_clock(&clk_xtal) < 0) 233 ret = s3c24xx_register_clock(clkp);
431 printk(KERN_ERR "failed to register master xtal\n"); 234 if (ret < 0) {
235 printk(KERN_ERR "Failed to register clock %s (%d)\n",
236 clkp->name, ret);
237 }
238 }
432 239
433 if (s3c24xx_register_clock(&clk_mpll) < 0) 240 /* We must be careful disabling the clocks we are not intending to
434 printk(KERN_ERR "failed to register mpll clock\n"); 241 * be using at boot time, as subsytems such as the LCD which do
242 * their own DMA requests to the bus can cause the system to lockup
243 * if they where in the middle of requesting bus access.
244 *
245 * Disabling the LCD clock if the LCD is active is very dangerous,
246 * and therefore the bootloader should be careful to not enable
247 * the LCD clock if it is not needed.
248 */
249
250 /* install (and disable) the clocks we do not need immediately */
251
252 clkp = init_clocks_disable;
253 for (ptr = 0; ptr < ARRAY_SIZE(init_clocks_disable); ptr++, clkp++) {
254
255 ret = s3c24xx_register_clock(clkp);
256 if (ret < 0) {
257 printk(KERN_ERR "Failed to register clock %s (%d)\n",
258 clkp->name, ret);
259 }
435 260
436 if (s3c24xx_register_clock(&clk_upll) < 0) 261 s3c2410_clkcon_enable(clkp, 0);
437 printk(KERN_ERR "failed to register upll clock\n"); 262 }
438 263
439 if (s3c24xx_register_clock(&clk_f) < 0) 264 /* show the clock-slow value */
440 printk(KERN_ERR "failed to register cpu fclk\n");
441 265
442 if (s3c24xx_register_clock(&clk_h) < 0) 266 xtal = clk_get(NULL, "xtal");
443 printk(KERN_ERR "failed to register cpu hclk\n");
444 267
445 if (s3c24xx_register_clock(&clk_p) < 0) 268 printk("CLOCK: Slow mode (%ld.%ld MHz), %s, MPLL %s, UPLL %s\n",
446 printk(KERN_ERR "failed to register cpu pclk\n"); 269 print_mhz(clk_get_rate(xtal) /
270 ( 2 * S3C2410_CLKSLOW_GET_SLOWVAL(clkslow))),
271 (clkslow & S3C2410_CLKSLOW_SLOW) ? "slow" : "fast",
272 (clkslow & S3C2410_CLKSLOW_MPLL_OFF) ? "off" : "on",
273 (clkslow & S3C2410_CLKSLOW_UCLK_OFF) ? "off" : "on");
447 274
448 return 0; 275 return 0;
449} 276}