aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/plat-samsung/pm.c
blob: 416e5bea54f9d029ab0d31198b2014bdbc463564 (plain)
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
/* linux/arch/arm/plat-s3c/pm.c
 *
 * Copyright 2008 Openmoko, Inc.
 * Copyright 2004-2008 Simtec Electronics
 *	Ben Dooks <ben@simtec.co.uk>
 *	http://armlinux.simtec.co.uk/
 *
 * S3C common power management (suspend to ram) support.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
*/

#include <linux/init.h>
#include <linux/suspend.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/serial_core.h>
#include <linux/io.h>

#include <asm/cacheflush.h>
#include <asm/suspend.h>

#include <plat/regs-serial.h>

#ifdef CONFIG_SAMSUNG_ATAGS
#include <mach/hardware.h>
#include <mach/map.h>
#include <mach/regs-clock.h>
#include <mach/regs-irq.h>
#include <mach/irqs.h>
#endif

#include <asm/irq.h>

#include <plat/pm.h>
#include <mach/pm-core.h>

/* for external use */

unsigned long s3c_pm_flags;

/* Debug code:
 *
 * This code supports debug output to the low level UARTs for use on
 * resume before the console layer is available.
*/

#ifdef CONFIG_SAMSUNG_PM_DEBUG
extern void printascii(const char *);

void s3c_pm_dbg(const char *fmt, ...)
{
	va_list va;
	char buff[256];

	va_start(va, fmt);
	vsnprintf(buff, sizeof(buff), fmt, va);
	va_end(va);

	printascii(buff);
}

static inline void s3c_pm_debug_init(void)
{
	/* restart uart clocks so we can use them to output */
	s3c_pm_debug_init_uart();
}

#else
#define s3c_pm_debug_init() do { } while(0)

#endif /* CONFIG_SAMSUNG_PM_DEBUG */

/* Save the UART configurations if we are configured for debug. */

unsigned char pm_uart_udivslot;

#ifdef CONFIG_SAMSUNG_PM_DEBUG

static struct pm_uart_save uart_save;

static void s3c_pm_save_uart(unsigned int uart, struct pm_uart_save *save)
{
	void __iomem *regs = S3C_VA_UARTx(uart);

	save->ulcon = __raw_readl(regs + S3C2410_ULCON);
	save->ucon = __raw_readl(regs + S3C2410_UCON);
	save->ufcon = __raw_readl(regs + S3C2410_UFCON);
	save->umcon = __raw_readl(regs + S3C2410_UMCON);
	save->ubrdiv = __raw_readl(regs + S3C2410_UBRDIV);

	if (pm_uart_udivslot)
		save->udivslot = __raw_readl(regs + S3C2443_DIVSLOT);

	S3C_PMDBG("UART[%d]: ULCON=%04x, UCON=%04x, UFCON=%04x, UBRDIV=%04x\n",
		  uart, save->ulcon, save->ucon, save->ufcon, save->ubrdiv);
}

static void s3c_pm_save_uarts(void)
{
	s3c_pm_save_uart(CONFIG_DEBUG_S3C_UART, &uart_save);
}

static void s3c_pm_restore_uart(unsigned int uart, struct pm_uart_save *save)
{
	void __iomem *regs = S3C_VA_UARTx(uart);

	s3c_pm_arch_update_uart(regs, save);

	__raw_writel(save->ulcon, regs + S3C2410_ULCON);
	__raw_writel(save->ucon,  regs + S3C2410_UCON);
	__raw_writel(save->ufcon, regs + S3C2410_UFCON);
	__raw_writel(save->umcon, regs + S3C2410_UMCON);
	__raw_writel(save->ubrdiv, regs + S3C2410_UBRDIV);

	if (pm_uart_udivslot)
		__raw_writel(save->udivslot, regs + S3C2443_DIVSLOT);
}

static void s3c_pm_restore_uarts(void)
{
	s3c_pm_restore_uart(CONFIG_DEBUG_S3C_UART, &uart_save);
}
#else
static void s3c_pm_save_uarts(void) { }
static void s3c_pm_restore_uarts(void) { }
#endif

/* The IRQ ext-int code goes here, it is too small to currently bother
 * with its own file. */

unsigned long s3c_irqwake_intmask	= 0xffffffffL;
unsigned long s3c_irqwake_eintmask	= 0xffffffffL;

int s3c_irqext_wake(struct irq_data *data, unsigned int state)
{
	unsigned long bit = 1L << IRQ_EINT_BIT(data->irq);

	if (!(s3c_irqwake_eintallow & bit))
		return -ENOENT;

	printk(KERN_INFO "wake %s for irq %d\n",
	       state ? "enabled" : "disabled", data->irq);

	if (!state)
		s3c_irqwake_eintmask |= bit;
	else
		s3c_irqwake_eintmask &= ~bit;

	return 0;
}

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

/**
 * s3c_pm_do_save() - save a set of registers for restoration on resume.
 * @ptr: Pointer to an array of registers.
 * @count: Size of the ptr array.
 *
 * Run through the list of registers given, saving their contents in the
 * array for later restoration when we wakeup.
 */
void s3c_pm_do_save(struct sleep_save *ptr, int count)
{
	for (; count > 0; count--, ptr++) {
		ptr->val = __raw_readl(ptr->reg);
		S3C_PMDBG("saved %p value %08lx\n", ptr->reg, ptr->val);
	}
}

/**
 * s3c_pm_do_restore() - restore register values from the save list.
 * @ptr: Pointer to an array of registers.
 * @count: Size of the ptr array.
 *
 * Restore the register values saved from s3c_pm_do_save().
 *
 * Note, we do not use S3C_PMDBG() in here, as the system may not have
 * restore the UARTs state yet
*/

void s3c_pm_do_restore(const 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);
	}
}

/**
 * s3c_pm_do_restore_core() - early restore register values from save list.
 *
 * This is similar to s3c_pm_do_restore() except we try and minimise the
 * side effects of the function in case registers that hardware might need
 * to work has been restored.
 *
 * WARNING: Do not put any debug in here that may effect memory or use
 * peripherals, as things may be changing!
*/

void s3c_pm_do_restore_core(const 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 __maybe_unused s3c_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)) {
			S3C_PMDBG("IRQ %d asserted at resume\n", start+i);
		}
	}
}


void (*pm_cpu_prep)(void);
int (*pm_cpu_sleep)(unsigned long);

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

/* s3c_pm_enter
 *
 * central control for sleep/resume process
*/

static int s3c_pm_enter(suspend_state_t state)
{
	int ret;
	/* ensure the debug is initialised (if enabled) */

	s3c_pm_debug_init();

	S3C_PMDBG("%s(%d)\n", __func__, state);

	if (pm_cpu_prep == NULL || pm_cpu_sleep == NULL) {
		printk(KERN_ERR "%s: error: no cpu sleep function\n", __func__);
		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 (!of_have_populated_dt() &&
	    !any_allowed(s3c_irqwake_intmask, s3c_irqwake_intallow) &&
	    !any_allowed(s3c_irqwake_eintmask, s3c_irqwake_eintallow)) {
		printk(KERN_ERR "%s: No wake-up sources!\n", __func__);
		printk(KERN_ERR "%s: Aborting sleep\n", __func__);
		return -EINVAL;
	}

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

	if (!of_have_populated_dt()) {
		samsung_pm_save_gpios();
		samsung_pm_saved_gpios();
	}

	s3c_pm_save_uarts();
	s3c_pm_save_core();

	/* set the irq configuration for wake */

	s3c_pm_configure_extint();

	S3C_PMDBG("sleep: irq wakeup masks: %08lx,%08lx\n",
	    s3c_irqwake_intmask, s3c_irqwake_eintmask);

	s3c_pm_arch_prepare_irqs();

	/* call cpu specific preparation */

	pm_cpu_prep();

	/* flush cache back to ram */

	flush_cache_all();

	s3c_pm_check_store();

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

	s3c_pm_arch_stop_clocks();

	/* this will also act as our return point from when
	 * we resume as it saves its own register state and restores it
	 * during the resume.  */

	ret = cpu_suspend(0, pm_cpu_sleep);
	if (ret)
		return ret;

	/* restore the system state */

	s3c_pm_restore_core();
	s3c_pm_restore_uarts();

	if (!of_have_populated_dt()) {
		samsung_pm_restore_gpios();
		s3c_pm_restored_gpios();
	}

	s3c_pm_debug_init();

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

	s3c_pm_arch_show_resume_irqs();

	S3C_PMDBG("%s: post sleep, preparing to return\n", __func__);

	/* LEDs should now be 1110 */
	s3c_pm_debug_smdkled(1 << 1, 0);

	s3c_pm_check_restore();

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

	S3C_PMDBG("S3C PM Resume (post-restore)\n");
	return 0;
}

static int s3c_pm_prepare(void)
{
	/* prepare check area if configured */

	s3c_pm_check_prepare();
	return 0;
}

static void s3c_pm_finish(void)
{
	s3c_pm_check_cleanup();
}

static const struct platform_suspend_ops s3c_pm_ops = {
	.enter		= s3c_pm_enter,
	.prepare	= s3c_pm_prepare,
	.finish		= s3c_pm_finish,
	.valid		= suspend_valid_only_mem,
};

/* s3c_pm_init
 *
 * Attach the power management functions. This should be called
 * from the board specific initialisation if the board supports
 * it.
*/

int __init s3c_pm_init(void)
{
	printk("S3C Power Management, Copyright 2004 Simtec Electronics\n");

	suspend_set_ops(&s3c_pm_ops);
	return 0;
}