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