kernel/arch/arm/mach-s5pv210/pm.c

   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(virt_to_phys(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         u32 tmp;
 159
 160         tmp = __raw_readl(S5P_OTHERS);
 161         tmp |= (S5P_OTHERS_RET_IO | S5P_OTHERS_RET_CF |\
 162                 S5P_OTHERS_RET_MMC | S5P_OTHERS_RET_UART);
 163         __raw_writel(tmp , S5P_OTHERS);
 164
 165         s3c_pm_do_restore_core(s5pv210_core_save, ARRAY_SIZE(s5pv210_core_save));
 166 }
 167
 168 static struct syscore_ops s5pv210_pm_syscore_ops = {
 169         .resume         = s5pv210_pm_resume,
 170 };
 171
 172 /*
 173  * Initialization entry point.
 174  */
 175 void __init s5pv210_pm_init(void)
 176 {
 177         register_syscore_ops(&s5pv210_pm_syscore_ops);
 178         suspend_set_ops(&s5pv210_suspend_ops);
 179 }