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 int rmobile_pd_attach_dev(struct generic_pm_domain *domain,
 105                                  struct device *dev)
 106 {
 107         int error;
 108
 109         error = pm_clk_create(dev);
 110         if (error) {
 111                 dev_err(dev, "pm_clk_create failed %d\n", error);
 112                 return error;
 113         }
 114
 115         error = pm_clk_add(dev, NULL);
 116         if (error) {
 117                 dev_err(dev, "pm_clk_add failed %d\n", error);
 118                 goto fail;
 119         }
 120
 121         return 0;
 122
 123 fail:
 124         pm_clk_destroy(dev);
 125         return error;
 126 }
 127
 128 static void rmobile_pd_detach_dev(struct generic_pm_domain *domain,
 129                                   struct device *dev)
 130 {
 131         pm_clk_destroy(dev);
 132 }
 133
 134 static void rmobile_init_pm_domain(struct rmobile_pm_domain *rmobile_pd)
 135 {
 136         struct generic_pm_domain *genpd = &rmobile_pd->genpd;
 137         struct dev_power_governor *gov = rmobile_pd->gov;
 138
 139         genpd->flags = GENPD_FLAG_PM_CLK;
 140         pm_genpd_init(genpd, gov ? : &simple_qos_governor, false);
 141         genpd->dev_ops.active_wakeup    = rmobile_pd_active_wakeup;
 142         genpd->power_off                = rmobile_pd_power_down;
 143         genpd->power_on                 = rmobile_pd_power_up;
 144         genpd->attach_dev               = rmobile_pd_attach_dev;
 145         genpd->detach_dev               = rmobile_pd_detach_dev;
 146         __rmobile_pd_power_up(rmobile_pd, false);
 147 }
 148
 149 void rmobile_init_domains(struct rmobile_pm_domain domains[], int num)
 150 {
 151         int j;
 152
 153         for (j = 0; j < num; j++)
 154                 rmobile_init_pm_domain(&domains[j]);
 155 }
 156
 157 void rmobile_add_device_to_domain_td(const char *domain_name,
 158                                      struct platform_device *pdev,
 159                                      struct gpd_timing_data *td)
 160 {
 161         struct device *dev = &pdev->dev;
 162
 163         __pm_genpd_name_add_device(domain_name, dev, td);
 164 }
 165
 166 void rmobile_add_devices_to_domains(struct pm_domain_device data[],
 167                                     int size)
 168 {
 169         struct gpd_timing_data latencies = {
 170                 .stop_latency_ns = DEFAULT_DEV_LATENCY_NS,
 171                 .start_latency_ns = DEFAULT_DEV_LATENCY_NS,
 172                 .save_state_latency_ns = DEFAULT_DEV_LATENCY_NS,
 173                 .restore_state_latency_ns = DEFAULT_DEV_LATENCY_NS,
 174         };
 175         int j;
 176
 177         for (j = 0; j < size; j++)
 178                 rmobile_add_device_to_domain_td(data[j].domain_name,
 179                                                 data[j].pdev, &latencies);
 180 }