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
42 unsigned 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
47 unsigned long s3c_irqwake_intmask = 0xffffffffL;
48 unsigned long s3c_irqwake_eintmask = 0xffffffffL;
49
s3c_irqext_wake(struct irq_data * data,unsigned int state)50 int 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
68 void (*pm_cpu_prep)(void);
69 int (*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
s3c_pm_enter(suspend_state_t state)78 static 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
s3c_pm_prepare(void)175 static int s3c_pm_prepare(void)
176 {
177 /* prepare check area if configured */
178
179 s3c_pm_check_prepare();
180 return 0;
181 }
182
s3c_pm_finish(void)183 static void s3c_pm_finish(void)
184 {
185 s3c_pm_check_cleanup();
186 }
187
188 static 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
s3c_pm_init(void)202 int __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