1/* linux/arch/arm/plat-s3c/pm.c
2 *
3 * Copyright 2008 Openmoko, Inc.
4 * Copyright 2004-2008 Simtec Electronics
5 *	Ben Dooks <ben@simtec.co.uk>
6 *	http://armlinux.simtec.co.uk/
7 *
8 * S3C common power management (suspend to ram) support.
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13*/
14
15#include <linux/init.h>
16#include <linux/suspend.h>
17#include <linux/errno.h>
18#include <linux/delay.h>
19#include <linux/of.h>
20#include <linux/serial_s3c.h>
21#include <linux/io.h>
22
23#include <asm/cacheflush.h>
24#include <asm/suspend.h>
25
26#ifdef CONFIG_SAMSUNG_ATAGS
27#include <mach/map.h>
28#ifndef CONFIG_ARCH_EXYNOS
29#include <mach/regs-clock.h>
30#include <mach/regs-irq.h>
31#endif
32#include <mach/irqs.h>
33#endif
34
35#include <asm/irq.h>
36
37#include <plat/pm.h>
38#include <mach/pm-core.h>
39
40/* for external use */
41
42unsigned long s3c_pm_flags;
43
44/* The IRQ ext-int code goes here, it is too small to currently bother
45 * with its own file. */
46
47unsigned long s3c_irqwake_intmask	= 0xffffffffL;
48unsigned long s3c_irqwake_eintmask	= 0xffffffffL;
49
50int s3c_irqext_wake(struct irq_data *data, unsigned int state)
51{
52	unsigned long bit = 1L << IRQ_EINT_BIT(data->irq);
53
54	if (!(s3c_irqwake_eintallow & bit))
55		return -ENOENT;
56
57	printk(KERN_INFO "wake %s for irq %d\n",
58	       state ? "enabled" : "disabled", data->irq);
59
60	if (!state)
61		s3c_irqwake_eintmask |= bit;
62	else
63		s3c_irqwake_eintmask &= ~bit;
64
65	return 0;
66}
67
68void (*pm_cpu_prep)(void);
69int (*pm_cpu_sleep)(unsigned long);
70
71#define any_allowed(mask, allow) (((mask) & (allow)) != (allow))
72
73/* s3c_pm_enter
74 *
75 * central control for sleep/resume process
76*/
77
78static int s3c_pm_enter(suspend_state_t state)
79{
80	int ret;
81	/* ensure the debug is initialised (if enabled) */
82
83	s3c_pm_debug_init();
84
85	S3C_PMDBG("%s(%d)\n", __func__, state);
86
87	if (pm_cpu_prep == NULL || pm_cpu_sleep == NULL) {
88		printk(KERN_ERR "%s: error: no cpu sleep function\n", __func__);
89		return -EINVAL;
90	}
91
92	/* check if we have anything to wake-up with... bad things seem
93	 * to happen if you suspend with no wakeup (system will often
94	 * require a full power-cycle)
95	*/
96
97	if (!of_have_populated_dt() &&
98	    !any_allowed(s3c_irqwake_intmask, s3c_irqwake_intallow) &&
99	    !any_allowed(s3c_irqwake_eintmask, s3c_irqwake_eintallow)) {
100		printk(KERN_ERR "%s: No wake-up sources!\n", __func__);
101		printk(KERN_ERR "%s: Aborting sleep\n", __func__);
102		return -EINVAL;
103	}
104
105	/* save all necessary core registers not covered by the drivers */
106
107	if (!of_have_populated_dt()) {
108		samsung_pm_save_gpios();
109		samsung_pm_saved_gpios();
110	}
111
112	s3c_pm_save_uarts();
113	s3c_pm_save_core();
114
115	/* set the irq configuration for wake */
116
117	s3c_pm_configure_extint();
118
119	S3C_PMDBG("sleep: irq wakeup masks: %08lx,%08lx\n",
120	    s3c_irqwake_intmask, s3c_irqwake_eintmask);
121
122	s3c_pm_arch_prepare_irqs();
123
124	/* call cpu specific preparation */
125
126	pm_cpu_prep();
127
128	/* flush cache back to ram */
129
130	flush_cache_all();
131
132	s3c_pm_check_store();
133
134	/* send the cpu to sleep... */
135
136	s3c_pm_arch_stop_clocks();
137
138	/* this will also act as our return point from when
139	 * we resume as it saves its own register state and restores it
140	 * during the resume.  */
141
142	ret = cpu_suspend(0, pm_cpu_sleep);
143	if (ret)
144		return ret;
145
146	/* restore the system state */
147
148	s3c_pm_restore_core();
149	s3c_pm_restore_uarts();
150
151	if (!of_have_populated_dt()) {
152		samsung_pm_restore_gpios();
153		s3c_pm_restored_gpios();
154	}
155
156	s3c_pm_debug_init();
157
158	/* check what irq (if any) restored the system */
159
160	s3c_pm_arch_show_resume_irqs();
161
162	S3C_PMDBG("%s: post sleep, preparing to return\n", __func__);
163
164	/* LEDs should now be 1110 */
165	s3c_pm_debug_smdkled(1 << 1, 0);
166
167	s3c_pm_check_restore();
168
169	/* ok, let's return from sleep */
170
171	S3C_PMDBG("S3C PM Resume (post-restore)\n");
172	return 0;
173}
174
175static int s3c_pm_prepare(void)
176{
177	/* prepare check area if configured */
178
179	s3c_pm_check_prepare();
180	return 0;
181}
182
183static void s3c_pm_finish(void)
184{
185	s3c_pm_check_cleanup();
186}
187
188static const struct platform_suspend_ops s3c_pm_ops = {
189	.enter		= s3c_pm_enter,
190	.prepare	= s3c_pm_prepare,
191	.finish		= s3c_pm_finish,
192	.valid		= suspend_valid_only_mem,
193};
194
195/* s3c_pm_init
196 *
197 * Attach the power management functions. This should be called
198 * from the board specific initialisation if the board supports
199 * it.
200*/
201
202int __init s3c_pm_init(void)
203{
204	printk("S3C Power Management, Copyright 2004 Simtec Electronics\n");
205
206	suspend_set_ops(&s3c_pm_ops);
207	return 0;
208}
209