arch/arm/mach-shmobile/pm-rmobile.c

   1 /*
   2  * rmobile power management support
   3  *
   4  * Copyright (C) 2012  Renesas Solutions Corp.
   5  * Copyright (C) 2012  Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
   6  *
   7  * based on pm-sh7372.c
   8  *  Copyright (C) 2011 Magnus Damm
   9  *
  10  * This file is subject to the terms and conditions of the GNU General Public
  11  * License.  See the file "COPYING" in the main directory of this archive
  12  * for more details.
  13  */
  14 #include <linux/console.h>
  15 #include <linux/delay.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/pm.h>
  18 #include <linux/pm_clock.h>
  19 #include <asm/io.h>
  20 #include <mach/pm-rmobile.h>
  21
  22 /* SYSC */
  23 #define SPDCR           IOMEM(0xe6180008)
  24 #define SWUCR           IOMEM(0xe6180014)
  25 #define PSTR            IOMEM(0xe6180080)
  26
  27 #define PSTR_RETRIES    100
  28 #define PSTR_DELAY_US   10
  29
  30 #ifdef CONFIG_PM
  31 static int rmobile_pd_power_down(struct generic_pm_domain *genpd)
  32 {
  33         struct rmobile_pm_domain *rmobile_pd = to_rmobile_pd(genpd);
  34         unsigned int mask = 1 << rmobile_pd->bit_shift;
  35
  36         if (rmobile_pd->suspend) {
  37                 int ret = rmobile_pd->suspend();
  38
  39                 if (ret)
  40                         return ret;
  41         }
  42
  43         if (__raw_readl(PSTR) & mask) {
  44                 unsigned int retry_count;
  45                 __raw_writel(mask, SPDCR);
  46
  47                 for (retry_count = PSTR_RETRIES; retry_count; retry_count--) {
  48                         if (!(__raw_readl(SPDCR) & mask))
  49                                 break;
  50                         cpu_relax();
  51                 }
  52         }
  53
  54         if (!rmobile_pd->no_debug)
  55                 pr_debug("%s: Power off, 0x%08x -> PSTR = 0x%08x\n",
  56                          genpd->name, mask, __raw_readl(PSTR));
  57
  58         return 0;
  59 }
  60
  61 static int __rmobile_pd_power_up(struct rmobile_pm_domain *rmobile_pd,
  62                                  bool do_resume)
  63 {
  64         unsigned int mask = 1 << rmobile_pd->bit_shift;
  65         unsigned int retry_count;
  66         int ret = 0;
  67
  68         if (__raw_readl(PSTR) & mask)
  69                 goto out;
  70
  71         __raw_writel(mask, SWUCR);
  72
  73         for (retry_count = 2 * PSTR_RETRIES; retry_count; retry_count--) {
  74                 if (!(__raw_readl(SWUCR) & mask))
  75                         break;
  76                 if (retry_count > PSTR_RETRIES)
  77                         udelay(PSTR_DELAY_US);
  78                 else
  79                         cpu_relax();
  80         }
  81         if (!retry_count)
  82                 ret = -EIO;
  83
  84         if (!rmobile_pd->no_debug)
  85                 pr_debug("%s: Power on, 0x%08x -> PSTR = 0x%08x\n",
  86                          rmobile_pd->genpd.name, mask, __raw_readl(PSTR));
  87
  88 out:
  89         if (ret == 0 && rmobile_pd->resume && do_resume)
  90                 rmobile_pd->resume();
  91
  92         return ret;
  93 }
  94
  95 static int rmobile_pd_power_up(struct generic_pm_domain *genpd)
  96 {
  97         return __rmobile_pd_power_up(to_rmobile_pd(genpd), true);
  98 }
  99
 100 static bool rmobile_pd_active_wakeup(struct device *dev)
 101 {
 102         bool (*active_wakeup)(struct device *dev);
 103
 104         active_wakeup = dev_gpd_data(dev)->ops.active_wakeup;
 105         return active_wakeup ? active_wakeup(dev) : true;
 106 }
 107
 108 static int rmobile_pd_stop_dev(struct device *dev)
 109 {
 110         int (*stop)(struct device *dev);
 111
 112         stop = dev_gpd_data(dev)->ops.stop;
 113         if (stop) {
 114                 int ret = stop(dev);
 115                 if (ret)
 116                         return ret;
 117         }
 118         return pm_clk_suspend(dev);
 119 }
 120
 121 static int rmobile_pd_start_dev(struct device *dev)
 122 {
 123         int (*start)(struct device *dev);
 124         int ret;
 125
 126         ret = pm_clk_resume(dev);
 127         if (ret)
 128                 return ret;
 129
 130         start = dev_gpd_data(dev)->ops.start;
 131         if (start)
 132                 ret = start(dev);
 133
 134         return ret;
 135 }
 136
 137 void rmobile_init_pm_domain(struct rmobile_pm_domain *rmobile_pd)
 138 {
 139         struct generic_pm_domain *genpd = &rmobile_pd->genpd;
 140         struct dev_power_governor *gov = rmobile_pd->gov;
 141
 142         pm_genpd_init(genpd, gov ? : &simple_qos_governor, false);
 143         genpd->dev_ops.stop             = rmobile_pd_stop_dev;
 144         genpd->dev_ops.start            = rmobile_pd_start_dev;
 145         genpd->dev_ops.active_wakeup    = rmobile_pd_active_wakeup;
 146         genpd->dev_irq_safe             = true;
 147         genpd->power_off                = rmobile_pd_power_down;
 148         genpd->power_on                 = rmobile_pd_power_up;
 149         __rmobile_pd_power_up(rmobile_pd, false);
 150 }
 151
 152 void rmobile_add_device_to_domain(struct rmobile_pm_domain *rmobile_pd,
 153                                  struct platform_device *pdev)
 154 {
 155         struct device *dev = &pdev->dev;
 156
 157         pm_genpd_add_device(&rmobile_pd->genpd, dev);
 158         if (pm_clk_no_clocks(dev))
 159                 pm_clk_add(dev, NULL);
 160 }
 161
 162 void rmobile_pm_add_subdomain(struct rmobile_pm_domain *rmobile_pd,
 163                              struct rmobile_pm_domain *rmobile_sd)
 164 {
 165         pm_genpd_add_subdomain(&rmobile_pd->genpd, &rmobile_sd->genpd);
 166 }
 167 #endif /* CONFIG_PM */