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 21 #include <mach/da8xx.h> 22 #include <mach/sram.h> 23 #include <mach/pm.h> 24 25 #include "clock.h" 26 27 #define DEEPSLEEP_SLEEPCOUNT_MASK 0xFFFF 28 29 static void (*davinci_sram_suspend) (struct davinci_pm_config *); 30 static struct davinci_pm_config *pdata; 31 32 static void davinci_sram_push(void *dest, void *src, unsigned int size) 33 { 34 memcpy(dest, src, size); 35 flush_icache_range((unsigned long)dest, (unsigned long)(dest + size)); 36 } 37 38 static void davinci_pm_suspend(void) 39 { 40 unsigned val; 41 42 if (pdata->cpupll_reg_base != pdata->ddrpll_reg_base) { 43 44 /* Switch CPU PLL to bypass mode */ 45 val = __raw_readl(pdata->cpupll_reg_base + PLLCTL); 46 val &= ~(PLLCTL_PLLENSRC | PLLCTL_PLLEN); 47 __raw_writel(val, pdata->cpupll_reg_base + PLLCTL); 48 49 udelay(PLL_BYPASS_TIME); 50 51 /* Powerdown CPU PLL */ 52 val = __raw_readl(pdata->cpupll_reg_base + PLLCTL); 53 val |= PLLCTL_PLLPWRDN; 54 __raw_writel(val, pdata->cpupll_reg_base + PLLCTL); 55 } 56 57 /* Configure sleep count in deep sleep register */ 58 val = __raw_readl(pdata->deepsleep_reg); 59 val &= ~DEEPSLEEP_SLEEPCOUNT_MASK, 60 val |= pdata->sleepcount; 61 __raw_writel(val, pdata->deepsleep_reg); 62 63 /* System goes to sleep in this call */ 64 davinci_sram_suspend(pdata); 65 66 if (pdata->cpupll_reg_base != pdata->ddrpll_reg_base) { 67 68 /* put CPU PLL in reset */ 69 val = __raw_readl(pdata->cpupll_reg_base + PLLCTL); 70 val &= ~PLLCTL_PLLRST; 71 __raw_writel(val, pdata->cpupll_reg_base + PLLCTL); 72 73 /* put CPU PLL in power down */ 74 val = __raw_readl(pdata->cpupll_reg_base + PLLCTL); 75 val &= ~PLLCTL_PLLPWRDN; 76 __raw_writel(val, pdata->cpupll_reg_base + PLLCTL); 77 78 /* wait for CPU PLL reset */ 79 udelay(PLL_RESET_TIME); 80 81 /* bring CPU PLL out of reset */ 82 val = __raw_readl(pdata->cpupll_reg_base + PLLCTL); 83 val |= PLLCTL_PLLRST; 84 __raw_writel(val, pdata->cpupll_reg_base + PLLCTL); 85 86 /* Wait for CPU PLL to lock */ 87 udelay(PLL_LOCK_TIME); 88 89 /* Remove CPU PLL from bypass mode */ 90 val = __raw_readl(pdata->cpupll_reg_base + PLLCTL); 91 val &= ~PLLCTL_PLLENSRC; 92 val |= PLLCTL_PLLEN; 93 __raw_writel(val, pdata->cpupll_reg_base + PLLCTL); 94 } 95 } 96 97 static int davinci_pm_enter(suspend_state_t state) 98 { 99 int ret = 0; 100 101 switch (state) { 102 case PM_SUSPEND_STANDBY: 103 case PM_SUSPEND_MEM: 104 davinci_pm_suspend(); 105 break; 106 default: 107 ret = -EINVAL; 108 } 109 110 return ret; 111 } 112 113 static struct platform_suspend_ops davinci_pm_ops = { 114 .enter = davinci_pm_enter, 115 .valid = suspend_valid_only_mem, 116 }; 117 118 static int __init davinci_pm_probe(struct platform_device *pdev) 119 { 120 pdata = pdev->dev.platform_data; 121 if (!pdata) { 122 dev_err(&pdev->dev, "cannot get platform data\n"); 123 return -ENOENT; 124 } 125 126 davinci_sram_suspend = sram_alloc(davinci_cpu_suspend_sz, NULL); 127 if (!davinci_sram_suspend) { 128 dev_err(&pdev->dev, "cannot allocate SRAM memory\n"); 129 return -ENOMEM; 130 } 131 132 davinci_sram_push(davinci_sram_suspend, davinci_cpu_suspend, 133 davinci_cpu_suspend_sz); 134 135 suspend_set_ops(&davinci_pm_ops); 136 137 return 0; 138 } 139 140 static int __exit davinci_pm_remove(struct platform_device *pdev) 141 { 142 sram_free(davinci_sram_suspend, davinci_cpu_suspend_sz); 143 return 0; 144 } 145 146 static struct platform_driver davinci_pm_driver = { 147 .driver = { 148 .name = "pm-davinci", 149 .owner = THIS_MODULE, 150 }, 151 .remove = __exit_p(davinci_pm_remove), 152 }; 153 154 static int __init davinci_pm_init(void) 155 { 156 return platform_driver_probe(&davinci_pm_driver, davinci_pm_probe); 157 } 158 late_initcall(davinci_pm_init); 159