arch/arm/mach-davinci/pm.c

   1 /*
   2  * DaVinci Power Management Routines
   3  *
   4  * Copyright (C) 2009 Texas Instruments, Inc. http://www.ti.com/
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/pm.h>
  12 #include <linux/suspend.h>
  13 #include <linux/module.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/clk.h>
  16 #include <linux/spinlock.h>
  17
  18 #include <asm/cacheflush.h>
  19 #include <asm/delay.h>
  20 #include <asm/io.h>
  21
  22 #include <mach/common.h>
  23 #include <mach/da8xx.h>
  24 #include <mach/mux.h>
  25 #include <mach/pm.h>
  26
  27 #include "clock.h"
  28 #include "psc.h"
  29 #include "sram.h"
  30
  31 #define DA850_PLL1_BASE         0x01e1a000
  32 #define DEEPSLEEP_SLEEPCOUNT_MASK       0xFFFF
  33 #define DEEPSLEEP_SLEEPCOUNT            128
  34
  35 static void (*davinci_sram_suspend) (struct davinci_pm_config *);
  36 static struct davinci_pm_config pm_config = {
  37         .sleepcount = DEEPSLEEP_SLEEPCOUNT,
  38         .ddrpsc_num = DA8XX_LPSC1_EMIF3C,
  39 };
  40
  41 static void davinci_sram_push(void *dest, void *src, unsigned int size)
  42 {
  43         memcpy(dest, src, size);
  44         flush_icache_range((unsigned long)dest, (unsigned long)(dest + size));
  45 }
  46
  47 static void davinci_pm_suspend(void)
  48 {
  49         unsigned val;
  50
  51         if (pm_config.cpupll_reg_base != pm_config.ddrpll_reg_base) {
  52
  53                 /* Switch CPU PLL to bypass mode */
  54                 val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
  55                 val &= ~(PLLCTL_PLLENSRC | PLLCTL_PLLEN);
  56                 __raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
  57
  58                 udelay(PLL_BYPASS_TIME);
  59
  60                 /* Powerdown CPU PLL */
  61                 val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
  62                 val |= PLLCTL_PLLPWRDN;
  63                 __raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
  64         }
  65
  66         /* Configure sleep count in deep sleep register */
  67         val = __raw_readl(pm_config.deepsleep_reg);
  68         val &= ~DEEPSLEEP_SLEEPCOUNT_MASK,
  69         val |= pm_config.sleepcount;
  70         __raw_writel(val, pm_config.deepsleep_reg);
  71
  72         /* System goes to sleep in this call */
  73         davinci_sram_suspend(&pm_config);
  74
  75         if (pm_config.cpupll_reg_base != pm_config.ddrpll_reg_base) {
  76
  77                 /* put CPU PLL in reset */
  78                 val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
  79                 val &= ~PLLCTL_PLLRST;
  80                 __raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
  81
  82                 /* put CPU PLL in power down */
  83                 val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
  84                 val &= ~PLLCTL_PLLPWRDN;
  85                 __raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
  86
  87                 /* wait for CPU PLL reset */
  88                 udelay(PLL_RESET_TIME);
  89
  90                 /* bring CPU PLL out of reset */
  91                 val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
  92                 val |= PLLCTL_PLLRST;
  93                 __raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
  94
  95                 /* Wait for CPU PLL to lock */
  96                 udelay(PLL_LOCK_TIME);
  97
  98                 /* Remove CPU PLL from bypass mode */
  99                 val = __raw_readl(pm_config.cpupll_reg_base + PLLCTL);
 100                 val &= ~PLLCTL_PLLENSRC;
 101                 val |= PLLCTL_PLLEN;
 102                 __raw_writel(val, pm_config.cpupll_reg_base + PLLCTL);
 103         }
 104 }
 105
 106 static int davinci_pm_enter(suspend_state_t state)
 107 {
 108         int ret = 0;
 109
 110         switch (state) {
 111         case PM_SUSPEND_MEM:
 112                 davinci_pm_suspend();
 113                 break;
 114         default:
 115                 ret = -EINVAL;
 116         }
 117
 118         return ret;
 119 }
 120
 121 static const struct platform_suspend_ops davinci_pm_ops = {
 122         .enter          = davinci_pm_enter,
 123         .valid          = suspend_valid_only_mem,
 124 };
 125
 126 int __init davinci_pm_init(void)
 127 {
 128         int ret;
 129
 130         ret = davinci_cfg_reg(DA850_RTC_ALARM);
 131         if (ret)
 132                 return ret;
 133
 134         pm_config.ddr2_ctlr_base = da8xx_get_mem_ctlr();
 135         pm_config.deepsleep_reg = DA8XX_SYSCFG1_VIRT(DA8XX_DEEPSLEEP_REG);
 136
 137         pm_config.cpupll_reg_base = ioremap(DA8XX_PLL0_BASE, SZ_4K);
 138         if (!pm_config.cpupll_reg_base)
 139                 return -ENOMEM;
 140
 141         pm_config.ddrpll_reg_base = ioremap(DA850_PLL1_BASE, SZ_4K);
 142         if (!pm_config.ddrpll_reg_base) {
 143                 ret = -ENOMEM;
 144                 goto no_ddrpll_mem;
 145         }
 146
 147         pm_config.ddrpsc_reg_base = ioremap(DA8XX_PSC1_BASE, SZ_4K);
 148         if (!pm_config.ddrpsc_reg_base) {
 149                 ret = -ENOMEM;
 150                 goto no_ddrpsc_mem;
 151         }
 152
 153         davinci_sram_suspend = sram_alloc(davinci_cpu_suspend_sz, NULL);
 154         if (!davinci_sram_suspend) {
 155                 pr_err("PM: cannot allocate SRAM memory\n");
 156                 ret = -ENOMEM;
 157                 goto no_sram_mem;
 158         }
 159
 160         davinci_sram_push(davinci_sram_suspend, davinci_cpu_suspend,
 161                                                 davinci_cpu_suspend_sz);
 162
 163         suspend_set_ops(&davinci_pm_ops);
 164
 165         return 0;
 166
 167 no_sram_mem:
 168         iounmap(pm_config.ddrpsc_reg_base);
 169 no_ddrpsc_mem:
 170         iounmap(pm_config.ddrpll_reg_base);
 171 no_ddrpll_mem:
 172         iounmap(pm_config.cpupll_reg_base);
 173         return ret;
 174 }