xref: /openbmc/linux/arch/arm/mach-s5pv210/pm.c (revision 588b48ca)
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 <mach/regs-clock.h>
28 
29 #include "common.h"
30 
31 static struct sleep_save s5pv210_core_save[] = {
32 	/* Clock ETC */
33 	SAVE_ITEM(S5P_MDNIE_SEL),
34 };
35 
36 /*
37  * VIC wake-up support (TODO)
38  */
39 static u32 s5pv210_irqwake_intmask = 0xffffffff;
40 
41 /*
42  * Suspend helpers.
43  */
44 static int s5pv210_cpu_suspend(unsigned long arg)
45 {
46 	unsigned long tmp;
47 
48 	/* issue the standby signal into the pm unit. Note, we
49 	 * issue a write-buffer drain just in case */
50 
51 	tmp = 0;
52 
53 	asm("b 1f\n\t"
54 	    ".align 5\n\t"
55 	    "1:\n\t"
56 	    "mcr p15, 0, %0, c7, c10, 5\n\t"
57 	    "mcr p15, 0, %0, c7, c10, 4\n\t"
58 	    "wfi" : : "r" (tmp));
59 
60 	pr_info("Failed to suspend the system\n");
61 	return 1; /* Aborting suspend */
62 }
63 
64 static void s5pv210_pm_prepare(void)
65 {
66 	unsigned int tmp;
67 
68 	/* Set wake-up mask registers */
69 	__raw_writel(exynos_get_eint_wake_mask(), S5P_EINT_WAKEUP_MASK);
70 	__raw_writel(s5pv210_irqwake_intmask, S5P_WAKEUP_MASK);
71 
72 	/* ensure at least INFORM0 has the resume address */
73 	__raw_writel(virt_to_phys(s5pv210_cpu_resume), S5P_INFORM0);
74 
75 	tmp = __raw_readl(S5P_SLEEP_CFG);
76 	tmp &= ~(S5P_SLEEP_CFG_OSC_EN | S5P_SLEEP_CFG_USBOSC_EN);
77 	__raw_writel(tmp, S5P_SLEEP_CFG);
78 
79 	/* WFI for SLEEP mode configuration by SYSCON */
80 	tmp = __raw_readl(S5P_PWR_CFG);
81 	tmp &= S5P_CFG_WFI_CLEAN;
82 	tmp |= S5P_CFG_WFI_SLEEP;
83 	__raw_writel(tmp, S5P_PWR_CFG);
84 
85 	/* SYSCON interrupt handling disable */
86 	tmp = __raw_readl(S5P_OTHERS);
87 	tmp |= S5P_OTHER_SYSC_INTOFF;
88 	__raw_writel(tmp, S5P_OTHERS);
89 
90 	s3c_pm_do_save(s5pv210_core_save, ARRAY_SIZE(s5pv210_core_save));
91 }
92 
93 /*
94  * Suspend operations.
95  */
96 static int s5pv210_suspend_enter(suspend_state_t state)
97 {
98 	int ret;
99 
100 	s3c_pm_debug_init();
101 
102 	S3C_PMDBG("%s: suspending the system...\n", __func__);
103 
104 	S3C_PMDBG("%s: wakeup masks: %08x,%08x\n", __func__,
105 			s5pv210_irqwake_intmask, exynos_get_eint_wake_mask());
106 
107 	if (s5pv210_irqwake_intmask == -1U
108 	    && exynos_get_eint_wake_mask() == -1U) {
109 		pr_err("%s: No wake-up sources!\n", __func__);
110 		pr_err("%s: Aborting sleep\n", __func__);
111 		return -EINVAL;
112 	}
113 
114 	s3c_pm_save_uarts();
115 	s5pv210_pm_prepare();
116 	flush_cache_all();
117 	s3c_pm_check_store();
118 
119 	ret = cpu_suspend(0, s5pv210_cpu_suspend);
120 	if (ret)
121 		return ret;
122 
123 	s3c_pm_restore_uarts();
124 
125 	S3C_PMDBG("%s: wakeup stat: %08x\n", __func__,
126 			__raw_readl(S5P_WAKEUP_STAT));
127 
128 	s3c_pm_check_restore();
129 
130 	S3C_PMDBG("%s: resuming the system...\n", __func__);
131 
132 	return 0;
133 }
134 
135 static int s5pv210_suspend_prepare(void)
136 {
137 	s3c_pm_check_prepare();
138 
139 	return 0;
140 }
141 
142 static void s5pv210_suspend_finish(void)
143 {
144 	s3c_pm_check_cleanup();
145 }
146 
147 static const struct platform_suspend_ops s5pv210_suspend_ops = {
148 	.enter		= s5pv210_suspend_enter,
149 	.prepare	= s5pv210_suspend_prepare,
150 	.finish		= s5pv210_suspend_finish,
151 	.valid		= suspend_valid_only_mem,
152 };
153 
154 /*
155  * Syscore operations used to delay restore of certain registers.
156  */
157 static void s5pv210_pm_resume(void)
158 {
159 	u32 tmp;
160 
161 	tmp = __raw_readl(S5P_OTHERS);
162 	tmp |= (S5P_OTHERS_RET_IO | S5P_OTHERS_RET_CF |\
163 		S5P_OTHERS_RET_MMC | S5P_OTHERS_RET_UART);
164 	__raw_writel(tmp , S5P_OTHERS);
165 
166 	s3c_pm_do_restore_core(s5pv210_core_save, ARRAY_SIZE(s5pv210_core_save));
167 }
168 
169 static struct syscore_ops s5pv210_pm_syscore_ops = {
170 	.resume		= s5pv210_pm_resume,
171 };
172 
173 /*
174  * Initialization entry point.
175  */
176 void __init s5pv210_pm_init(void)
177 {
178 	register_syscore_ops(&s5pv210_pm_syscore_ops);
179 	suspend_set_ops(&s5pv210_suspend_ops);
180 }
181