arch/arm/mach-prima2/pm.c

   1 /*
   2  * power management entry for CSR SiRFprimaII
   3  *
   4  * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
   5  *
   6  * Licensed under GPLv2 or later.
   7  */
   8
   9 #include <linux/kernel.h>
  10 #include <linux/suspend.h>
  11 #include <linux/slab.h>
  12 #include <linux/export.h>
  13 #include <linux/of.h>
  14 #include <linux/of_address.h>
  15 #include <linux/of_device.h>
  16 #include <linux/of_platform.h>
  17 #include <linux/io.h>
  18 #include <linux/rtc/sirfsoc_rtciobrg.h>
  19 #include <asm/suspend.h>
  20 #include <asm/hardware/cache-l2x0.h>
  21
  22 #include "pm.h"
  23
  24 /*
  25  * suspend asm codes will access these to make DRAM become self-refresh and
  26  * system sleep
  27  */
  28 u32 sirfsoc_pwrc_base;
  29 void __iomem *sirfsoc_memc_base;
  30
  31 static void sirfsoc_set_wakeup_source(void)
  32 {
  33         u32 pwr_trigger_en_reg;
  34         pwr_trigger_en_reg = sirfsoc_rtc_iobrg_readl(sirfsoc_pwrc_base +
  35                 SIRFSOC_PWRC_TRIGGER_EN);
  36 #define X_ON_KEY_B (1 << 0)
  37 #define RTC_ALARM0_B (1 << 2)
  38 #define RTC_ALARM1_B (1 << 3)
  39         sirfsoc_rtc_iobrg_writel(pwr_trigger_en_reg | X_ON_KEY_B |
  40                 RTC_ALARM0_B | RTC_ALARM1_B,
  41                 sirfsoc_pwrc_base + SIRFSOC_PWRC_TRIGGER_EN);
  42 }
  43
  44 static void sirfsoc_set_sleep_mode(u32 mode)
  45 {
  46         u32 sleep_mode = sirfsoc_rtc_iobrg_readl(sirfsoc_pwrc_base +
  47                 SIRFSOC_PWRC_PDN_CTRL);
  48         sleep_mode &= ~(SIRFSOC_SLEEP_MODE_MASK << 1);
  49         sleep_mode |= mode << 1;
  50         sirfsoc_rtc_iobrg_writel(sleep_mode, sirfsoc_pwrc_base +
  51                 SIRFSOC_PWRC_PDN_CTRL);
  52 }
  53
  54 static int sirfsoc_pre_suspend_power_off(void)
  55 {
  56         u32 wakeup_entry = virt_to_phys(cpu_resume);
  57
  58         sirfsoc_rtc_iobrg_writel(wakeup_entry, sirfsoc_pwrc_base +
  59                 SIRFSOC_PWRC_SCRATCH_PAD1);
  60
  61         sirfsoc_set_wakeup_source();
  62
  63         sirfsoc_set_sleep_mode(SIRFSOC_DEEP_SLEEP_MODE);
  64
  65         return 0;
  66 }
  67
  68 static int sirfsoc_pm_enter(suspend_state_t state)
  69 {
  70         switch (state) {
  71         case PM_SUSPEND_MEM:
  72                 sirfsoc_pre_suspend_power_off();
  73
  74                 outer_disable();
  75                 /* go zzz */
  76                 cpu_suspend(0, sirfsoc_finish_suspend);
  77                 outer_resume();
  78                 break;
  79         default:
  80                 return -EINVAL;
  81         }
  82         return 0;
  83 }
  84
  85 static const struct platform_suspend_ops sirfsoc_pm_ops = {
  86         .enter = sirfsoc_pm_enter,
  87         .valid = suspend_valid_only_mem,
  88 };
  89
  90 static const struct of_device_id pwrc_ids[] = {
  91         { .compatible = "sirf,prima2-pwrc" },
  92         {}
  93 };
  94
  95 static int __init sirfsoc_of_pwrc_init(void)
  96 {
  97         struct device_node *np;
  98
  99         np = of_find_matching_node(NULL, pwrc_ids);
 100         if (!np) {
 101                 pr_err("unable to find compatible sirf pwrc node in dtb\n");
 102                 return -ENOENT;
 103         }
 104
 105         /*
 106          * pwrc behind rtciobrg is not located in memory space
 107          * though the property is named reg. reg only means base
 108          * offset for pwrc. then of_iomap is not suitable here.
 109          */
 110         if (of_property_read_u32(np, "reg", &sirfsoc_pwrc_base))
 111                 panic("unable to find base address of pwrc node in dtb\n");
 112
 113         of_node_put(np);
 114
 115         return 0;
 116 }
 117
 118 static const struct of_device_id memc_ids[] = {
 119         { .compatible = "sirf,prima2-memc" },
 120         {}
 121 };
 122
 123 static int sirfsoc_memc_probe(struct platform_device *op)
 124 {
 125         struct device_node *np = op->dev.of_node;
 126
 127         sirfsoc_memc_base = of_iomap(np, 0);
 128         if (!sirfsoc_memc_base)
 129                 panic("unable to map memc registers\n");
 130
 131         return 0;
 132 }
 133
 134 static struct platform_driver sirfsoc_memc_driver = {
 135         .probe          = sirfsoc_memc_probe,
 136         .driver = {
 137                 .name = "sirfsoc-memc",
 138                 .of_match_table = memc_ids,
 139         },
 140 };
 141
 142 static int __init sirfsoc_memc_init(void)
 143 {
 144         return platform_driver_register(&sirfsoc_memc_driver);
 145 }
 146
 147 int __init sirfsoc_pm_init(void)
 148 {
 149         sirfsoc_of_pwrc_init();
 150         sirfsoc_memc_init();
 151         suspend_set_ops(&sirfsoc_pm_ops);
 152         return 0;
 153 }