xref: /openbmc/linux/arch/arm/mach-s5pv210/pm.c (revision 4f6cce39)
1 /* linux/arch/arm/mach-s5pv210/pm.c
2  *
3  * Copyright (c) 2010-2014 Samsung Electronics Co., Ltd.
4  *		http://www.samsung.com
5  *
6  * S5PV210 - Power Management support
7  *
8  * Based on arch/arm/mach-s3c2410/pm.c
9  * Copyright (c) 2006 Simtec Electronics
10  *	Ben Dooks <ben@simtec.co.uk>
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License version 2 as
14  * published by the Free Software Foundation.
15 */
16 
17 #include <linux/init.h>
18 #include <linux/suspend.h>
19 #include <linux/syscore_ops.h>
20 #include <linux/io.h>
21 
22 #include <asm/cacheflush.h>
23 #include <asm/suspend.h>
24 
25 #include <plat/pm-common.h>
26 
27 #include "common.h"
28 #include "regs-clock.h"
29 
30 static struct sleep_save s5pv210_core_save[] = {
31 	/* Clock ETC */
32 	SAVE_ITEM(S5P_MDNIE_SEL),
33 };
34 
35 /*
36  * VIC wake-up support (TODO)
37  */
38 static u32 s5pv210_irqwake_intmask = 0xffffffff;
39 
40 /*
41  * Suspend helpers.
42  */
43 static int s5pv210_cpu_suspend(unsigned long arg)
44 {
45 	unsigned long tmp;
46 
47 	/* issue the standby signal into the pm unit. Note, we
48 	 * issue a write-buffer drain just in case */
49 
50 	tmp = 0;
51 
52 	asm("b 1f\n\t"
53 	    ".align 5\n\t"
54 	    "1:\n\t"
55 	    "mcr p15, 0, %0, c7, c10, 5\n\t"
56 	    "mcr p15, 0, %0, c7, c10, 4\n\t"
57 	    "wfi" : : "r" (tmp));
58 
59 	pr_info("Failed to suspend the system\n");
60 	return 1; /* Aborting suspend */
61 }
62 
63 static void s5pv210_pm_prepare(void)
64 {
65 	unsigned int tmp;
66 
67 	/* Set wake-up mask registers */
68 	__raw_writel(exynos_get_eint_wake_mask(), S5P_EINT_WAKEUP_MASK);
69 	__raw_writel(s5pv210_irqwake_intmask, S5P_WAKEUP_MASK);
70 
71 	/* ensure at least INFORM0 has the resume address */
72 	__raw_writel(__pa_symbol(s5pv210_cpu_resume), S5P_INFORM0);
73 
74 	tmp = __raw_readl(S5P_SLEEP_CFG);
75 	tmp &= ~(S5P_SLEEP_CFG_OSC_EN | S5P_SLEEP_CFG_USBOSC_EN);
76 	__raw_writel(tmp, S5P_SLEEP_CFG);
77 
78 	/* WFI for SLEEP mode configuration by SYSCON */
79 	tmp = __raw_readl(S5P_PWR_CFG);
80 	tmp &= S5P_CFG_WFI_CLEAN;
81 	tmp |= S5P_CFG_WFI_SLEEP;
82 	__raw_writel(tmp, S5P_PWR_CFG);
83 
84 	/* SYSCON interrupt handling disable */
85 	tmp = __raw_readl(S5P_OTHERS);
86 	tmp |= S5P_OTHER_SYSC_INTOFF;
87 	__raw_writel(tmp, S5P_OTHERS);
88 
89 	s3c_pm_do_save(s5pv210_core_save, ARRAY_SIZE(s5pv210_core_save));
90 }
91 
92 /*
93  * Suspend operations.
94  */
95 static int s5pv210_suspend_enter(suspend_state_t state)
96 {
97 	int ret;
98 
99 	s3c_pm_debug_init();
100 
101 	S3C_PMDBG("%s: suspending the system...\n", __func__);
102 
103 	S3C_PMDBG("%s: wakeup masks: %08x,%08x\n", __func__,
104 			s5pv210_irqwake_intmask, exynos_get_eint_wake_mask());
105 
106 	if (s5pv210_irqwake_intmask == -1U
107 	    && exynos_get_eint_wake_mask() == -1U) {
108 		pr_err("%s: No wake-up sources!\n", __func__);
109 		pr_err("%s: Aborting sleep\n", __func__);
110 		return -EINVAL;
111 	}
112 
113 	s3c_pm_save_uarts();
114 	s5pv210_pm_prepare();
115 	flush_cache_all();
116 	s3c_pm_check_store();
117 
118 	ret = cpu_suspend(0, s5pv210_cpu_suspend);
119 	if (ret)
120 		return ret;
121 
122 	s3c_pm_restore_uarts();
123 
124 	S3C_PMDBG("%s: wakeup stat: %08x\n", __func__,
125 			__raw_readl(S5P_WAKEUP_STAT));
126 
127 	s3c_pm_check_restore();
128 
129 	S3C_PMDBG("%s: resuming the system...\n", __func__);
130 
131 	return 0;
132 }
133 
134 static int s5pv210_suspend_prepare(void)
135 {
136 	s3c_pm_check_prepare();
137 
138 	return 0;
139 }
140 
141 static void s5pv210_suspend_finish(void)
142 {
143 	s3c_pm_check_cleanup();
144 }
145 
146 static const struct platform_suspend_ops s5pv210_suspend_ops = {
147 	.enter		= s5pv210_suspend_enter,
148 	.prepare	= s5pv210_suspend_prepare,
149 	.finish		= s5pv210_suspend_finish,
150 	.valid		= suspend_valid_only_mem,
151 };
152 
153 /*
154  * Syscore operations used to delay restore of certain registers.
155  */
156 static void s5pv210_pm_resume(void)
157 {
158 	s3c_pm_do_restore_core(s5pv210_core_save, ARRAY_SIZE(s5pv210_core_save));
159 }
160 
161 static struct syscore_ops s5pv210_pm_syscore_ops = {
162 	.resume		= s5pv210_pm_resume,
163 };
164 
165 /*
166  * Initialization entry point.
167  */
168 void __init s5pv210_pm_init(void)
169 {
170 	register_syscore_ops(&s5pv210_pm_syscore_ops);
171 	suspend_set_ops(&s5pv210_suspend_ops);
172 }
173