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/sram.h> 25 #include <mach/pm.h> 26 27 #include "clock.h" 28 29 #define DEEPSLEEP_SLEEPCOUNT_MASK 0xFFFF 30 31 static void (*davinci_sram_suspend) (struct davinci_pm_config *); 32 static struct davinci_pm_config *pdata; 33 34 static void davinci_sram_push(void *dest, void *src, unsigned int size) 35 { 36 memcpy(dest, src, size); 37 flush_icache_range((unsigned long)dest, (unsigned long)(dest + size)); 38 } 39 40 static void davinci_pm_suspend(void) 41 { 42 unsigned val; 43 44 if (pdata->cpupll_reg_base != pdata->ddrpll_reg_base) { 45 46 /* Switch CPU PLL to bypass mode */ 47 val = __raw_readl(pdata->cpupll_reg_base + PLLCTL); 48 val &= ~(PLLCTL_PLLENSRC | PLLCTL_PLLEN); 49 __raw_writel(val, pdata->cpupll_reg_base + PLLCTL); 50 51 udelay(PLL_BYPASS_TIME); 52 53 /* Powerdown CPU PLL */ 54 val = __raw_readl(pdata->cpupll_reg_base + PLLCTL); 55 val |= PLLCTL_PLLPWRDN; 56 __raw_writel(val, pdata->cpupll_reg_base + PLLCTL); 57 } 58 59 /* Configure sleep count in deep sleep register */ 60 val = __raw_readl(pdata->deepsleep_reg); 61 val &= ~DEEPSLEEP_SLEEPCOUNT_MASK, 62 val |= pdata->sleepcount; 63 __raw_writel(val, pdata->deepsleep_reg); 64 65 /* System goes to sleep in this call */ 66 davinci_sram_suspend(pdata); 67 68 if (pdata->cpupll_reg_base != pdata->ddrpll_reg_base) { 69 70 /* put CPU PLL in reset */ 71 val = __raw_readl(pdata->cpupll_reg_base + PLLCTL); 72 val &= ~PLLCTL_PLLRST; 73 __raw_writel(val, pdata->cpupll_reg_base + PLLCTL); 74 75 /* put CPU PLL in power down */ 76 val = __raw_readl(pdata->cpupll_reg_base + PLLCTL); 77 val &= ~PLLCTL_PLLPWRDN; 78 __raw_writel(val, pdata->cpupll_reg_base + PLLCTL); 79 80 /* wait for CPU PLL reset */ 81 udelay(PLL_RESET_TIME); 82 83 /* bring CPU PLL out of reset */ 84 val = __raw_readl(pdata->cpupll_reg_base + PLLCTL); 85 val |= PLLCTL_PLLRST; 86 __raw_writel(val, pdata->cpupll_reg_base + PLLCTL); 87 88 /* Wait for CPU PLL to lock */ 89 udelay(PLL_LOCK_TIME); 90 91 /* Remove CPU PLL from bypass mode */ 92 val = __raw_readl(pdata->cpupll_reg_base + PLLCTL); 93 val &= ~PLLCTL_PLLENSRC; 94 val |= PLLCTL_PLLEN; 95 __raw_writel(val, pdata->cpupll_reg_base + PLLCTL); 96 } 97 } 98 99 static int davinci_pm_enter(suspend_state_t state) 100 { 101 int ret = 0; 102 103 switch (state) { 104 case PM_SUSPEND_STANDBY: 105 case PM_SUSPEND_MEM: 106 davinci_pm_suspend(); 107 break; 108 default: 109 ret = -EINVAL; 110 } 111 112 return ret; 113 } 114 115 static const struct platform_suspend_ops davinci_pm_ops = { 116 .enter = davinci_pm_enter, 117 .valid = suspend_valid_only_mem, 118 }; 119 120 static int __init davinci_pm_probe(struct platform_device *pdev) 121 { 122 pdata = pdev->dev.platform_data; 123 if (!pdata) { 124 dev_err(&pdev->dev, "cannot get platform data\n"); 125 return -ENOENT; 126 } 127 128 davinci_sram_suspend = sram_alloc(davinci_cpu_suspend_sz, NULL); 129 if (!davinci_sram_suspend) { 130 dev_err(&pdev->dev, "cannot allocate SRAM memory\n"); 131 return -ENOMEM; 132 } 133 134 davinci_sram_push(davinci_sram_suspend, davinci_cpu_suspend, 135 davinci_cpu_suspend_sz); 136 137 suspend_set_ops(&davinci_pm_ops); 138 139 return 0; 140 } 141 142 static int __exit davinci_pm_remove(struct platform_device *pdev) 143 { 144 sram_free(davinci_sram_suspend, davinci_cpu_suspend_sz); 145 return 0; 146 } 147 148 static struct platform_driver davinci_pm_driver = { 149 .driver = { 150 .name = "pm-davinci", 151 .owner = THIS_MODULE, 152 }, 153 .remove = __exit_p(davinci_pm_remove), 154 }; 155 156 int __init davinci_pm_init(void) 157 { 158 return platform_driver_probe(&davinci_pm_driver, davinci_pm_probe); 159 } 160