linux/arch/arm/mach-shmobile/pm-r8a7779.c
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   1/*
   2 * r8a7779 Power management support
   3 *
   4 * Copyright (C) 2011  Renesas Solutions Corp.
   5 * Copyright (C) 2011  Magnus Damm
   6 *
   7 * This file is subject to the terms and conditions of the GNU General Public
   8 * License.  See the file "COPYING" in the main directory of this archive
   9 * for more details.
  10 */
  11
  12#include <linux/pm.h>
  13#include <linux/suspend.h>
  14#include <linux/err.h>
  15#include <linux/pm_clock.h>
  16#include <linux/platform_device.h>
  17#include <linux/delay.h>
  18#include <linux/irq.h>
  19#include <linux/interrupt.h>
  20#include <linux/console.h>
  21#include <asm/io.h>
  22#include <mach/common.h>
  23#include <mach/r8a7779.h>
  24
  25static void __iomem *r8a7779_sysc_base;
  26
  27/* SYSC */
  28#define SYSCSR 0x00
  29#define SYSCISR 0x04
  30#define SYSCISCR 0x08
  31#define SYSCIER 0x0c
  32#define SYSCIMR 0x10
  33#define PWRSR0 0x40
  34#define PWRSR1 0x80
  35#define PWRSR2 0xc0
  36#define PWRSR3 0x100
  37#define PWRSR4 0x140
  38
  39#define PWRSR_OFFS 0x00
  40#define PWROFFCR_OFFS 0x04
  41#define PWRONCR_OFFS 0x0c
  42#define PWRER_OFFS 0x14
  43
  44#define SYSCSR_RETRIES 100
  45#define SYSCSR_DELAY_US 1
  46
  47#define SYSCISR_RETRIES 1000
  48#define SYSCISR_DELAY_US 1
  49
  50#if defined(CONFIG_PM) || defined(CONFIG_SMP)
  51
  52static DEFINE_SPINLOCK(r8a7779_sysc_lock); /* SMP CPUs + I/O devices */
  53
  54static int r8a7779_sysc_pwr_on_off(struct r8a7779_pm_ch *r8a7779_ch,
  55                                   int sr_bit, int reg_offs)
  56{
  57        int k;
  58
  59        for (k = 0; k < SYSCSR_RETRIES; k++) {
  60                if (ioread32(r8a7779_sysc_base + SYSCSR) & (1 << sr_bit))
  61                        break;
  62                udelay(SYSCSR_DELAY_US);
  63        }
  64
  65        if (k == SYSCSR_RETRIES)
  66                return -EAGAIN;
  67
  68        iowrite32(1 << r8a7779_ch->chan_bit,
  69                  r8a7779_sysc_base + r8a7779_ch->chan_offs + reg_offs);
  70
  71        return 0;
  72}
  73
  74static int r8a7779_sysc_pwr_off(struct r8a7779_pm_ch *r8a7779_ch)
  75{
  76        return r8a7779_sysc_pwr_on_off(r8a7779_ch, 0, PWROFFCR_OFFS);
  77}
  78
  79static int r8a7779_sysc_pwr_on(struct r8a7779_pm_ch *r8a7779_ch)
  80{
  81        return r8a7779_sysc_pwr_on_off(r8a7779_ch, 1, PWRONCR_OFFS);
  82}
  83
  84static int r8a7779_sysc_update(struct r8a7779_pm_ch *r8a7779_ch,
  85                               int (*on_off_fn)(struct r8a7779_pm_ch *))
  86{
  87        unsigned int isr_mask = 1 << r8a7779_ch->isr_bit;
  88        unsigned int chan_mask = 1 << r8a7779_ch->chan_bit;
  89        unsigned int status;
  90        unsigned long flags;
  91        int ret = 0;
  92        int k;
  93
  94        spin_lock_irqsave(&r8a7779_sysc_lock, flags);
  95
  96        iowrite32(isr_mask, r8a7779_sysc_base + SYSCISCR);
  97
  98        do {
  99                ret = on_off_fn(r8a7779_ch);
 100                if (ret)
 101                        goto out;
 102
 103                status = ioread32(r8a7779_sysc_base +
 104                                  r8a7779_ch->chan_offs + PWRER_OFFS);
 105        } while (status & chan_mask);
 106
 107        for (k = 0; k < SYSCISR_RETRIES; k++) {
 108                if (ioread32(r8a7779_sysc_base + SYSCISR) & isr_mask)
 109                        break;
 110                udelay(SYSCISR_DELAY_US);
 111        }
 112
 113        if (k == SYSCISR_RETRIES)
 114                ret = -EIO;
 115
 116        iowrite32(isr_mask, r8a7779_sysc_base + SYSCISCR);
 117
 118 out:
 119        spin_unlock_irqrestore(&r8a7779_sysc_lock, flags);
 120
 121        pr_debug("r8a7779 power domain %d: %02x %02x %02x %02x %02x -> %d\n",
 122                 r8a7779_ch->isr_bit, ioread32(r8a7779_sysc_base + PWRSR0),
 123                 ioread32(r8a7779_sysc_base + PWRSR1),
 124                 ioread32(r8a7779_sysc_base + PWRSR2),
 125                 ioread32(r8a7779_sysc_base + PWRSR3),
 126                 ioread32(r8a7779_sysc_base + PWRSR4), ret);
 127        return ret;
 128}
 129
 130int r8a7779_sysc_power_down(struct r8a7779_pm_ch *r8a7779_ch)
 131{
 132        return r8a7779_sysc_update(r8a7779_ch, r8a7779_sysc_pwr_off);
 133}
 134
 135int r8a7779_sysc_power_up(struct r8a7779_pm_ch *r8a7779_ch)
 136{
 137        return r8a7779_sysc_update(r8a7779_ch, r8a7779_sysc_pwr_on);
 138}
 139
 140static void __init r8a7779_sysc_init(void)
 141{
 142        r8a7779_sysc_base = ioremap_nocache(0xffd85000, PAGE_SIZE);
 143        if (!r8a7779_sysc_base)
 144                panic("unable to ioremap r8a7779 SYSC hardware block\n");
 145
 146        /* enable all interrupt sources, but do not use interrupt handler */
 147        iowrite32(0x0131000e, r8a7779_sysc_base + SYSCIER);
 148        iowrite32(0, r8a7779_sysc_base + SYSCIMR);
 149}
 150
 151#else /* CONFIG_PM || CONFIG_SMP */
 152
 153static inline void r8a7779_sysc_init(void) {}
 154
 155#endif /* CONFIG_PM || CONFIG_SMP */
 156
 157#ifdef CONFIG_PM
 158
 159static int pd_power_down(struct generic_pm_domain *genpd)
 160{
 161        return r8a7779_sysc_power_down(to_r8a7779_ch(genpd));
 162}
 163
 164static int pd_power_up(struct generic_pm_domain *genpd)
 165{
 166        return r8a7779_sysc_power_up(to_r8a7779_ch(genpd));
 167}
 168
 169static bool pd_is_off(struct generic_pm_domain *genpd)
 170{
 171        struct r8a7779_pm_ch *r8a7779_ch = to_r8a7779_ch(genpd);
 172        unsigned int st;
 173
 174        st = ioread32(r8a7779_sysc_base + r8a7779_ch->chan_offs + PWRSR_OFFS);
 175        if (st & (1 << r8a7779_ch->chan_bit))
 176                return true;
 177
 178        return false;
 179}
 180
 181static bool pd_active_wakeup(struct device *dev)
 182{
 183        return true;
 184}
 185
 186static void r8a7779_init_pm_domain(struct r8a7779_pm_domain *r8a7779_pd)
 187{
 188        struct generic_pm_domain *genpd = &r8a7779_pd->genpd;
 189
 190        pm_genpd_init(genpd, NULL, false);
 191        genpd->dev_ops.stop = pm_clk_suspend;
 192        genpd->dev_ops.start = pm_clk_resume;
 193        genpd->dev_ops.active_wakeup = pd_active_wakeup;
 194        genpd->dev_irq_safe = true;
 195        genpd->power_off = pd_power_down;
 196        genpd->power_on = pd_power_up;
 197
 198        if (pd_is_off(&r8a7779_pd->genpd))
 199                pd_power_up(&r8a7779_pd->genpd);
 200}
 201
 202static struct r8a7779_pm_domain r8a7779_pm_domains[] = {
 203        {
 204                .genpd.name = "SH4A",
 205                .ch = {
 206                        .chan_offs = 0x80, /* PWRSR1 .. PWRER1 */
 207                        .isr_bit = 16, /* SH4A */
 208                },
 209        },
 210        {
 211                .genpd.name = "SGX",
 212                .ch = {
 213                        .chan_offs = 0xc0, /* PWRSR2 .. PWRER2 */
 214                        .isr_bit = 20, /* SGX */
 215                },
 216        },
 217        {
 218                .genpd.name = "VDP1",
 219                .ch = {
 220                        .chan_offs = 0x100, /* PWRSR3 .. PWRER3 */
 221                        .isr_bit = 21, /* VDP */
 222                },
 223        },
 224        {
 225                .genpd.name = "IMPX3",
 226                .ch = {
 227                        .chan_offs = 0x140, /* PWRSR4 .. PWRER4 */
 228                        .isr_bit = 24, /* IMP */
 229                },
 230        },
 231};
 232
 233void __init r8a7779_init_pm_domains(void)
 234{
 235        int j;
 236
 237        for (j = 0; j < ARRAY_SIZE(r8a7779_pm_domains); j++)
 238                r8a7779_init_pm_domain(&r8a7779_pm_domains[j]);
 239}
 240
 241#endif /* CONFIG_PM */
 242
 243void __init r8a7779_pm_init(void)
 244{
 245        static int once;
 246
 247        if (!once++)
 248                r8a7779_sysc_init();
 249}
 250