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 /* s3c2410_pm_show_resume_irqs
69 *
70 * print any IRQs asserted at resume time (ie, we woke from)
71 */
s3c_pm_show_resume_irqs(int start,unsigned long which,unsigned long mask)72 static void __maybe_unused s3c_pm_show_resume_irqs(int start,
73 unsigned long which,
74 unsigned long mask)
75 {
76 int i;
77
78 which &= ~mask;
79
80 for (i = 0; i <= 31; i++) {
81 if (which & (1L<<i)) {
82 S3C_PMDBG("IRQ %d asserted at resume\n", start+i);
83 }
84 }
85 }
86
87
88 void (*pm_cpu_prep)(void);
89 int (*pm_cpu_sleep)(unsigned long);
90
91 #define any_allowed(mask, allow) (((mask) & (allow)) != (allow))
92
93 /* s3c_pm_enter
94 *
95 * central control for sleep/resume process
96 */
97
s3c_pm_enter(suspend_state_t state)98 static int s3c_pm_enter(suspend_state_t state)
99 {
100 int ret;
101 /* ensure the debug is initialised (if enabled) */
102
103 s3c_pm_debug_init();
104
105 S3C_PMDBG("%s(%d)\n", __func__, state);
106
107 if (pm_cpu_prep == NULL || pm_cpu_sleep == NULL) {
108 printk(KERN_ERR "%s: error: no cpu sleep function\n", __func__);
109 return -EINVAL;
110 }
111
112 /* check if we have anything to wake-up with... bad things seem
113 * to happen if you suspend with no wakeup (system will often
114 * require a full power-cycle)
115 */
116
117 if (!of_have_populated_dt() &&
118 !any_allowed(s3c_irqwake_intmask, s3c_irqwake_intallow) &&
119 !any_allowed(s3c_irqwake_eintmask, s3c_irqwake_eintallow)) {
120 printk(KERN_ERR "%s: No wake-up sources!\n", __func__);
121 printk(KERN_ERR "%s: Aborting sleep\n", __func__);
122 return -EINVAL;
123 }
124
125 /* save all necessary core registers not covered by the drivers */
126
127 if (!of_have_populated_dt()) {
128 samsung_pm_save_gpios();
129 samsung_pm_saved_gpios();
130 }
131
132 s3c_pm_save_uarts();
133 s3c_pm_save_core();
134
135 /* set the irq configuration for wake */
136
137 s3c_pm_configure_extint();
138
139 S3C_PMDBG("sleep: irq wakeup masks: %08lx,%08lx\n",
140 s3c_irqwake_intmask, s3c_irqwake_eintmask);
141
142 s3c_pm_arch_prepare_irqs();
143
144 /* call cpu specific preparation */
145
146 pm_cpu_prep();
147
148 /* flush cache back to ram */
149
150 flush_cache_all();
151
152 s3c_pm_check_store();
153
154 /* send the cpu to sleep... */
155
156 s3c_pm_arch_stop_clocks();
157
158 /* this will also act as our return point from when
159 * we resume as it saves its own register state and restores it
160 * during the resume. */
161
162 ret = cpu_suspend(0, pm_cpu_sleep);
163 if (ret)
164 return ret;
165
166 /* restore the system state */
167
168 s3c_pm_restore_core();
169 s3c_pm_restore_uarts();
170
171 if (!of_have_populated_dt()) {
172 samsung_pm_restore_gpios();
173 s3c_pm_restored_gpios();
174 }
175
176 s3c_pm_debug_init();
177
178 /* check what irq (if any) restored the system */
179
180 s3c_pm_arch_show_resume_irqs();
181
182 S3C_PMDBG("%s: post sleep, preparing to return\n", __func__);
183
184 /* LEDs should now be 1110 */
185 s3c_pm_debug_smdkled(1 << 1, 0);
186
187 s3c_pm_check_restore();
188
189 /* ok, let's return from sleep */
190
191 S3C_PMDBG("S3C PM Resume (post-restore)\n");
192 return 0;
193 }
194
s3c_pm_prepare(void)195 static int s3c_pm_prepare(void)
196 {
197 /* prepare check area if configured */
198
199 s3c_pm_check_prepare();
200 return 0;
201 }
202
s3c_pm_finish(void)203 static void s3c_pm_finish(void)
204 {
205 s3c_pm_check_cleanup();
206 }
207
208 static const struct platform_suspend_ops s3c_pm_ops = {
209 .enter = s3c_pm_enter,
210 .prepare = s3c_pm_prepare,
211 .finish = s3c_pm_finish,
212 .valid = suspend_valid_only_mem,
213 };
214
215 /* s3c_pm_init
216 *
217 * Attach the power management functions. This should be called
218 * from the board specific initialisation if the board supports
219 * it.
220 */
221
s3c_pm_init(void)222 int __init s3c_pm_init(void)
223 {
224 printk("S3C Power Management, Copyright 2004 Simtec Electronics\n");
225
226 suspend_set_ops(&s3c_pm_ops);
227 return 0;
228 }
229