aboutsummaryrefslogblamecommitdiffstats
path: root/arch/arm/plat-s3c24xx/pm.c
blob: c6b03f8ab2602076c58c86a7ae6d7a8318b095b7 (plain) (tree)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
































































































































































































































































































































































































































































































































                                                                               




































































































                                                                               
                                       
                                           
                                            















                                                                          
/* linux/arch/arm/plat-s3c24xx/pm.c
 *
 * Copyright (c) 2004,2006 Simtec Electronics
 *	Ben Dooks <ben@simtec.co.uk>
 *
 * S3C24XX Power Manager (Suspend-To-RAM) support
 *
 * See Documentation/arm/Samsung-S3C24XX/Suspend.txt for more information
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Parts based on arch/arm/mach-pxa/pm.c
 *
 * Thanks to Dimitry Andric for debugging
*/

#include <linux/init.h>
#include <linux/suspend.h>
#include <linux/errno.h>
#include <linux/time.h>
#include <linux/interrupt.h>
#include <linux/crc32.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/serial_core.h>

#include <asm/cacheflush.h>
#include <asm/hardware.h>
#include <asm/io.h>

#include <asm/arch/regs-serial.h>
#include <asm/arch/regs-clock.h>
#include <asm/arch/regs-gpio.h>
#include <asm/arch/regs-mem.h>
#include <asm/arch/regs-irq.h>

#include <asm/mach/time.h>

#include <asm/plat-s3c24xx/pm.h>

/* for external use */

unsigned long s3c_pm_flags;

#define PFX "s3c24xx-pm: "

static struct sleep_save core_save[] = {
	SAVE_ITEM(S3C2410_LOCKTIME),
	SAVE_ITEM(S3C2410_CLKCON),

	/* we restore the timings here, with the proviso that the board
	 * brings the system up in an slower, or equal frequency setting
	 * to the original system.
	 *
	 * if we cannot guarantee this, then things are going to go very
	 * wrong here, as we modify the refresh and both pll settings.
	 */

	SAVE_ITEM(S3C2410_BWSCON),
	SAVE_ITEM(S3C2410_BANKCON0),
	SAVE_ITEM(S3C2410_BANKCON1),
	SAVE_ITEM(S3C2410_BANKCON2),
	SAVE_ITEM(S3C2410_BANKCON3),
	SAVE_ITEM(S3C2410_BANKCON4),
	SAVE_ITEM(S3C2410_BANKCON5),

	SAVE_ITEM(S3C2410_CLKDIVN),
	SAVE_ITEM(S3C2410_MPLLCON),
	SAVE_ITEM(S3C2410_UPLLCON),
	SAVE_ITEM(S3C2410_CLKSLOW),
	SAVE_ITEM(S3C2410_REFRESH),
};

static struct sleep_save gpio_save[] = {
	SAVE_ITEM(S3C2410_GPACON),
	SAVE_ITEM(S3C2410_GPADAT),

	SAVE_ITEM(S3C2410_GPBCON),
	SAVE_ITEM(S3C2410_GPBDAT),
	SAVE_ITEM(S3C2410_GPBUP),

	SAVE_ITEM(S3C2410_GPCCON),
	SAVE_ITEM(S3C2410_GPCDAT),
	SAVE_ITEM(S3C2410_GPCUP),

	SAVE_ITEM(S3C2410_GPDCON),
	SAVE_ITEM(S3C2410_GPDDAT),
	SAVE_ITEM(S3C2410_GPDUP),

	SAVE_ITEM(S3C2410_GPECON),
	SAVE_ITEM(S3C2410_GPEDAT),
	SAVE_ITEM(S3C2410_GPEUP),

	SAVE_ITEM(S3C2410_GPFCON),
	SAVE_ITEM(S3C2410_GPFDAT),
	SAVE_ITEM(S3C2410_GPFUP),

	SAVE_ITEM(S3C2410_GPGCON),
	SAVE_ITEM(S3C2410_GPGDAT),
	SAVE_ITEM(S3C2410_GPGUP),

	SAVE_ITEM(S3C2410_GPHCON),
	SAVE_ITEM(S3C2410_GPHDAT),
	SAVE_ITEM(S3C2410_GPHUP),

	SAVE_ITEM(S3C2410_DCLKCON),
};

#ifdef CONFIG_S3C2410_PM_DEBUG

#define SAVE_UART(va) \
	SAVE_ITEM((va) + S3C2410_ULCON), \
	SAVE_ITEM((va) + S3C2410_UCON), \
	SAVE_ITEM((va) + S3C2410_UFCON), \
	SAVE_ITEM((va) + S3C2410_UMCON), \
	SAVE_ITEM((va) + S3C2410_UBRDIV)

static struct sleep_save uart_save[] = {
	SAVE_UART(S3C24XX_VA_UART0),
	SAVE_UART(S3C24XX_VA_UART1),
#ifndef CONFIG_CPU_S3C2400
	SAVE_UART(S3C24XX_VA_UART2),
#endif
};

/* debug
 *
 * we send the debug to printascii() to allow it to be seen if the
 * system never wakes up from the sleep
*/

extern void printascii(const char *);

void pm_dbg(const char *fmt, ...)
{
	va_list va;
	char buff[256];

	va_start(va, fmt);
	vsprintf(buff, fmt, va);
	va_end(va);

	printascii(buff);
}

static void s3c2410_pm_debug_init(void)
{
	unsigned long tmp = __raw_readl(S3C2410_CLKCON);

	/* re-start uart clocks */
	tmp |= S3C2410_CLKCON_UART0;
	tmp |= S3C2410_CLKCON_UART1;
	tmp |= S3C2410_CLKCON_UART2;

	__raw_writel(tmp, S3C2410_CLKCON);
	udelay(10);
}

#define DBG(fmt...) pm_dbg(fmt)
#else
#define DBG(fmt...) printk(KERN_DEBUG fmt)

#define s3c2410_pm_debug_init() do { } while(0)

static struct sleep_save uart_save[] = {};
#endif

#if defined(CONFIG_S3C2410_PM_CHECK) && CONFIG_S3C2410_PM_CHECK_CHUNKSIZE != 0

/* suspend checking code...
 *
 * this next area does a set of crc checks over all the installed
 * memory, so the system can verify if the resume was ok.
 *
 * CONFIG_S3C2410_PM_CHECK_CHUNKSIZE defines the block-size for the CRC,
 * increasing it will mean that the area corrupted will be less easy to spot,
 * and reducing the size will cause the CRC save area to grow
*/

#define CHECK_CHUNKSIZE (CONFIG_S3C2410_PM_CHECK_CHUNKSIZE * 1024)

static u32 crc_size;	/* size needed for the crc block */
static u32 *crcs;	/* allocated over suspend/resume */

typedef u32 *(run_fn_t)(struct resource *ptr, u32 *arg);

/* s3c2410_pm_run_res
 *
 * go thorugh the given resource list, and look for system ram
*/

static void s3c2410_pm_run_res(struct resource *ptr, run_fn_t fn, u32 *arg)
{
	while (ptr != NULL) {
		if (ptr->child != NULL)
			s3c2410_pm_run_res(ptr->child, fn, arg);

		if ((ptr->flags & IORESOURCE_MEM) &&
		    strcmp(ptr->name, "System RAM") == 0) {
			DBG("Found system RAM at %08lx..%08lx\n",
			    ptr->start, ptr->end);
			arg = (fn)(ptr, arg);
		}

		ptr = ptr->sibling;
	}
}

static void s3c2410_pm_run_sysram(run_fn_t fn, u32 *arg)
{
	s3c2410_pm_run_res(&iomem_resource, fn, arg);
}

static u32 *s3c2410_pm_countram(struct resource *res, u32 *val)
{
	u32 size = (u32)(res->end - res->start)+1;

	size += CHECK_CHUNKSIZE-1;
	size /= CHECK_CHUNKSIZE;

	DBG("Area %08lx..%08lx, %d blocks\n", res->start, res->end, size);

	*val += size * sizeof(u32);
	return val;
}

/* s3c2410_pm_prepare_check
 *
 * prepare the necessary information for creating the CRCs. This
 * must be done before the final save, as it will require memory
 * allocating, and thus touching bits of the kernel we do not
 * know about.
*/

static void s3c2410_pm_check_prepare(void)
{
	crc_size = 0;

	s3c2410_pm_run_sysram(s3c2410_pm_countram, &crc_size);

	DBG("s3c2410_pm_prepare_check: %u checks needed\n", crc_size);

	crcs = kmalloc(crc_size+4, GFP_KERNEL);
	if (crcs == NULL)
		printk(KERN_ERR "Cannot allocated CRC save area\n");
}

static u32 *s3c2410_pm_makecheck(struct resource *res, u32 *val)
{
	unsigned long addr, left;

	for (addr = res->start; addr < res->end;
	     addr += CHECK_CHUNKSIZE) {
		left = res->end - addr;

		if (left > CHECK_CHUNKSIZE)
			left = CHECK_CHUNKSIZE;

		*val = crc32_le(~0, phys_to_virt(addr), left);
		val++;
	}

	return val;
}

/* s3c2410_pm_check_store
 *
 * compute the CRC values for the memory blocks before the final
 * sleep.
*/

static void s3c2410_pm_check_store(void)
{
	if (crcs != NULL)
		s3c2410_pm_run_sysram(s3c2410_pm_makecheck, crcs);
}

/* in_region
 *
 * return TRUE if the area defined by ptr..ptr+size contatins the
 * what..what+whatsz
*/

static inline int in_region(void *ptr, int size, void *what, size_t whatsz)
{
	if ((what+whatsz) < ptr)
		return 0;

	if (what > (ptr+size))
		return 0;

	return 1;
}

static u32 *s3c2410_pm_runcheck(struct resource *res, u32 *val)
{
	void *save_at = phys_to_virt(s3c2410_sleep_save_phys);
	unsigned long addr;
	unsigned long left;
	void *ptr;
	u32 calc;

	for (addr = res->start; addr < res->end;
	     addr += CHECK_CHUNKSIZE) {
		left = res->end - addr;

		if (left > CHECK_CHUNKSIZE)
			left = CHECK_CHUNKSIZE;

		ptr = phys_to_virt(addr);

		if (in_region(ptr, left, crcs, crc_size)) {
			DBG("skipping %08lx, has crc block in\n", addr);
			goto skip_check;
		}

		if (in_region(ptr, left, save_at, 32*4 )) {
			DBG("skipping %08lx, has save block in\n", addr);
			goto skip_check;
		}

		/* calculate and check the checksum */

		calc = crc32_le(~0, ptr, left);
		if (calc != *val) {
			printk(KERN_ERR PFX "Restore CRC error at "
			       "%08lx (%08x vs %08x)\n", addr, calc, *val);

			DBG("Restore CRC error at %08lx (%08x vs %08x)\n",
			    addr, calc, *val);
		}

	skip_check:
		val++;
	}

	return val;
}

/* s3c2410_pm_check_restore
 *
 * check the CRCs after the restore event and free the memory used
 * to hold them
*/

static void s3c2410_pm_check_restore(void)
{
	if (crcs != NULL) {
		s3c2410_pm_run_sysram(s3c2410_pm_runcheck, crcs);
		kfree(crcs);
		crcs = NULL;
	}
}

#else

#define s3c2410_pm_check_prepare() do { } while(0)
#define s3c2410_pm_check_restore() do { } while(0)
#define s3c2410_pm_check_store()   do { } while(0)
#endif

/* helper functions to save and restore register state */

void s3c2410_pm_do_save(struct sleep_save *ptr, int count)
{
	for (; count > 0; count--, ptr++) {
		ptr->val = __raw_readl(ptr->reg);
		DBG("saved %p value %08lx\n", ptr->reg, ptr->val);
	}
}

/* s3c2410_pm_do_restore
 *
 * restore the system from the given list of saved registers
 *
 * Note, we do not use DBG() in here, as the system may not have
 * restore the UARTs state yet
*/

void s3c2410_pm_do_restore(struct sleep_save *ptr, int count)
{
	for (; count > 0; count--, ptr++) {
		printk(KERN_DEBUG "restore %p (restore %08lx, was %08x)\n",
		       ptr->reg, ptr->val, __raw_readl(ptr->reg));

		__raw_writel(ptr->val, ptr->reg);
	}
}

/* s3c2410_pm_do_restore_core
 *
 * similar to s3c2410_pm_do_restore_core
 *
 * WARNING: Do not put any debug in here that may effect memory or use
 * peripherals, as things may be changing!
*/

static void s3c2410_pm_do_restore_core(struct sleep_save *ptr, int count)
{
	for (; count > 0; count--, ptr++) {
		__raw_writel(ptr->val, ptr->reg);
	}
}

/* s3c2410_pm_show_resume_irqs
 *
 * print any IRQs asserted at resume time (ie, we woke from)
*/

static void s3c2410_pm_show_resume_irqs(int start, unsigned long which,
					unsigned long mask)
{
	int i;

	which &= ~mask;

	for (i = 0; i <= 31; i++) {
		if ((which) & (1L<<i)) {
			DBG("IRQ %d asserted at resume\n", start+i);
		}
	}
}

/* s3c2410_pm_check_resume_pin
 *
 * check to see if the pin is configured correctly for sleep mode, and
 * make any necessary adjustments if it is not
*/

static void s3c2410_pm_check_resume_pin(unsigned int pin, unsigned int irqoffs)
{
	unsigned long irqstate;
	unsigned long pinstate;
	int irq = s3c2410_gpio_getirq(pin);

	if (irqoffs < 4)
		irqstate = s3c_irqwake_intmask & (1L<<irqoffs);
	else
		irqstate = s3c_irqwake_eintmask & (1L<<irqoffs);

	pinstate = s3c2410_gpio_getcfg(pin);

	if (!irqstate) {
		if (pinstate == S3C2410_GPIO_IRQ)
			DBG("Leaving IRQ %d (pin %d) enabled\n", irq, pin);
	} else {
		if (pinstate == S3C2410_GPIO_IRQ) {
			DBG("Disabling IRQ %d (pin %d)\n", irq, pin);
			s3c2410_gpio_cfgpin(pin, S3C2410_GPIO_INPUT);
		}
	}
}

/* s3c2410_pm_configure_extint
 *
 * configure all external interrupt pins
*/

static void s3c2410_pm_configure_extint(void)
{
	int pin;

	/* for each of the external interrupts (EINT0..EINT15) we
	 * need to check wether it is an external interrupt source,
	 * and then configure it as an input if it is not
	*/

	for (pin = S3C2410_GPF0; pin <= S3C2410_GPF7; pin++) {
		s3c2410_pm_check_resume_pin(pin, pin - S3C2410_GPF0);
	}

	for (pin = S3C2410_GPG0; pin <= S3C2410_GPG7; pin++) {
		s3c2410_pm_check_resume_pin(pin, (pin - S3C2410_GPG0)+8);
	}
}

void (*pm_cpu_prep)(void);
void (*pm_cpu_sleep)(void);

#define any_allowed(mask, allow) (((mask) & (allow)) != (allow))

/* s3c2410_pm_enter
 *
 * central control for sleep/resume process
*/

static int s3c2410_pm_enter(suspend_state_t state)
{
	unsigned long regs_save[16];

	/* ensure the debug is initialised (if enabled) */

	s3c2410_pm_debug_init();

	DBG("s3c2410_pm_enter(%d)\n", state);

	if (pm_cpu_prep == NULL || pm_cpu_sleep == NULL) {
		printk(KERN_ERR PFX "error: no cpu sleep functions set\n");
		return -EINVAL;
	}

	/* check if we have anything to wake-up with... bad things seem
	 * to happen if you suspend with no wakeup (system will often
	 * require a full power-cycle)
	*/

	if (!any_allowed(s3c_irqwake_intmask, s3c_irqwake_intallow) &&
	    !any_allowed(s3c_irqwake_eintmask, s3c_irqwake_eintallow)) {
		printk(KERN_ERR PFX "No sources enabled for wake-up!\n");
		printk(KERN_ERR PFX "Aborting sleep\n");
		return -EINVAL;
	}

	/* prepare check area if configured */

	s3c2410_pm_check_prepare();

	/* store the physical address of the register recovery block */

	s3c2410_sleep_save_phys = virt_to_phys(regs_save);

	DBG("s3c2410_sleep_save_phys=0x%08lx\n", s3c2410_sleep_save_phys);

	/* save all necessary core registers not covered by the drivers */

	s3c2410_pm_do_save(gpio_save, ARRAY_SIZE(gpio_save));
	s3c2410_pm_do_save(core_save, ARRAY_SIZE(core_save));
	s3c2410_pm_do_save(uart_save, ARRAY_SIZE(uart_save));

	/* set the irq configuration for wake */

	s3c2410_pm_configure_extint();

	DBG("sleep: irq wakeup masks: %08lx,%08lx\n",
	    s3c_irqwake_intmask, s3c_irqwake_eintmask);

	__raw_writel(s3c_irqwake_intmask, S3C2410_INTMSK);
	__raw_writel(s3c_irqwake_eintmask, S3C2410_EINTMASK);

	/* ack any outstanding external interrupts before we go to sleep */

	__raw_writel(__raw_readl(S3C2410_EINTPEND), S3C2410_EINTPEND);
	__raw_writel(__raw_readl(S3C2410_INTPND), S3C2410_INTPND);
	__raw_writel(__raw_readl(S3C2410_SRCPND), S3C2410_SRCPND);

	/* call cpu specific preperation */

	pm_cpu_prep();

	/* flush cache back to ram */

	flush_cache_all();

	s3c2410_pm_check_store();

	/* send the cpu to sleep... */

	__raw_writel(0x00, S3C2410_CLKCON);  /* turn off clocks over sleep */

	/* s3c2410_cpu_save will also act as our return point from when
	 * we resume as it saves its own register state, so use the return
	 * code to differentiate return from save and return from sleep */

	if (s3c2410_cpu_save(regs_save) == 0) {
		flush_cache_all();
		pm_cpu_sleep();
	}

	/* restore the cpu state */

	cpu_init();

	/* restore the system state */

	s3c2410_pm_do_restore_core(core_save, ARRAY_SIZE(core_save));
	s3c2410_pm_do_restore(gpio_save, ARRAY_SIZE(gpio_save));
	s3c2410_pm_do_restore(uart_save, ARRAY_SIZE(uart_save));

	s3c2410_pm_debug_init();

	/* check what irq (if any) restored the system */

	DBG("post sleep: IRQs 0x%08x, 0x%08x\n",
	    __raw_readl(S3C2410_SRCPND),
	    __raw_readl(S3C2410_EINTPEND));

	s3c2410_pm_show_resume_irqs(IRQ_EINT0, __raw_readl(S3C2410_SRCPND),
				    s3c_irqwake_intmask);

	s3c2410_pm_show_resume_irqs(IRQ_EINT4-4, __raw_readl(S3C2410_EINTPEND),
				    s3c_irqwake_eintmask);

	DBG("post sleep, preparing to return\n");

	s3c2410_pm_check_restore();

	/* ok, let's return from sleep */

	DBG("S3C2410 PM Resume (post-restore)\n");
	return 0;
}

static struct pm_ops s3c2410_pm_ops = {
	.enter		= s3c2410_pm_enter,
	.valid		= pm_valid_only_mem,
};

/* s3c2410_pm_init
 *
 * Attach the power management functions. This should be called
 * from the board specific initialisation if the board supports
 * it.
*/

int __init s3c2410_pm_init(void)
{
	printk("S3C2410 Power Management, (c) 2004 Simtec Electronics\n");

	pm_set_ops(&s3c2410_pm_ops);
	return 0;
}