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 "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 static int rmobile_pd_power_down(struct generic_pm_domain *genpd)
  31 {
  32         struct rmobile_pm_domain *rmobile_pd = to_rmobile_pd(genpd);
  33         unsigned int mask = 1 << rmobile_pd->bit_shift;
  34
  35         if (rmobile_pd->suspend) {
  36                 int ret = rmobile_pd->suspend();
  37
  38                 if (ret)
  39                         return ret;
  40         }
  41
  42         if (__raw_readl(PSTR) & mask) {
  43                 unsigned int retry_count;
  44                 __raw_writel(mask, SPDCR);
  45
  46                 for (retry_count = PSTR_RETRIES; retry_count; retry_count--) {
  47                         if (!(__raw_readl(SPDCR) & mask))
  48                                 break;
  49                         cpu_relax();
  50                 }
  51         }
  52
  53         if (!rmobile_pd->no_debug)
  54                 pr_debug("%s: Power off, 0x%08x -> PSTR = 0x%08x\n",
  55                          genpd->name, mask, __raw_readl(PSTR));
  56
  57         return 0;
  58 }
  59
  60 static int __rmobile_pd_power_up(struct rmobile_pm_domain *rmobile_pd,
  61                                  bool do_resume)
  62 {
  63         unsigned int mask = 1 << rmobile_pd->bit_shift;
  64         unsigned int retry_count;
  65         int ret = 0;
  66
  67         if (__raw_readl(PSTR) & mask)
  68                 goto out;
  69
  70         __raw_writel(mask, SWUCR);
  71
  72         for (retry_count = 2 * PSTR_RETRIES; retry_count; retry_count--) {
  73                 if (!(__raw_readl(SWUCR) & mask))
  74                         break;
  75                 if (retry_count > PSTR_RETRIES)
  76                         udelay(PSTR_DELAY_US);
  77                 else
  78                         cpu_relax();
  79         }
  80         if (!retry_count)
  81                 ret = -EIO;
  82
  83         if (!rmobile_pd->no_debug)
  84                 pr_debug("%s: Power on, 0x%08x -> PSTR = 0x%08x\n",
  85                          rmobile_pd->genpd.name, mask, __raw_readl(PSTR));
  86
  87 out:
  88         if (ret == 0 && rmobile_pd->resume && do_resume)
  89                 rmobile_pd->resume();
  90
  91         return ret;
  92 }
  93
  94 static int rmobile_pd_power_up(struct generic_pm_domain *genpd)
  95 {
  96         return __rmobile_pd_power_up(to_rmobile_pd(genpd), true);
  97 }
  98
  99 static bool rmobile_pd_active_wakeup(struct device *dev)
 100 {
 101         return true;
 102 }
 103
 104 static void rmobile_init_pm_domain(struct rmobile_pm_domain *rmobile_pd)
 105 {
 106         struct generic_pm_domain *genpd = &rmobile_pd->genpd;
 107         struct dev_power_governor *gov = rmobile_pd->gov;
 108
 109         pm_genpd_init(genpd, gov ? : &simple_qos_governor, false);
 110         genpd->dev_ops.stop             = pm_clk_suspend;
 111         genpd->dev_ops.start            = pm_clk_resume;
 112         genpd->dev_ops.active_wakeup    = rmobile_pd_active_wakeup;
 113         genpd->dev_irq_safe             = true;
 114         genpd->power_off                = rmobile_pd_power_down;
 115         genpd->power_on                 = rmobile_pd_power_up;
 116         __rmobile_pd_power_up(rmobile_pd, false);
 117 }
 118
 119 void rmobile_init_domains(struct rmobile_pm_domain domains[], int num)
 120 {
 121         int j;
 122
 123         for (j = 0; j < num; j++)
 124                 rmobile_init_pm_domain(&domains[j]);
 125 }
 126
 127 void rmobile_add_device_to_domain_td(const char *domain_name,
 128                                      struct platform_device *pdev,
 129                                      struct gpd_timing_data *td)
 130 {
 131         struct device *dev = &pdev->dev;
 132
 133         __pm_genpd_name_add_device(domain_name, dev, td);
 134         if (pm_clk_no_clocks(dev))
 135                 pm_clk_add(dev, NULL);
 136 }
 137
 138 void rmobile_add_devices_to_domains(struct pm_domain_device data[],
 139                                     int size)
 140 {
 141         struct gpd_timing_data latencies = {
 142                 .stop_latency_ns = DEFAULT_DEV_LATENCY_NS,
 143                 .start_latency_ns = DEFAULT_DEV_LATENCY_NS,
 144                 .save_state_latency_ns = DEFAULT_DEV_LATENCY_NS,
 145                 .restore_state_latency_ns = DEFAULT_DEV_LATENCY_NS,
 146         };
 147         int j;
 148
 149         for (j = 0; j < size; j++)
 150                 rmobile_add_device_to_domain_td(data[j].domain_name,
 151                                                 data[j].pdev, &latencies);
 152 }