1/* linux/arch/arm/plat-s3c/pm.c 2 * 3 * Copyright 2008 Openmoko, Inc. 4 * Copyright 2004-2008 Simtec Electronics 5 * Ben Dooks <ben@simtec.co.uk> 6 * http://armlinux.simtec.co.uk/ 7 * 8 * S3C common power management (suspend to ram) support. 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License version 2 as 12 * published by the Free Software Foundation. 13*/ 14 15#include <linux/init.h> 16#include <linux/suspend.h> 17#include <linux/errno.h> 18#include <linux/delay.h> 19#include <linux/of.h> 20#include <linux/serial_s3c.h> 21#include <linux/io.h> 22 23#include <asm/cacheflush.h> 24#include <asm/suspend.h> 25 26#ifdef CONFIG_SAMSUNG_ATAGS 27#include <mach/map.h> 28#ifndef CONFIG_ARCH_EXYNOS 29#include <mach/regs-clock.h> 30#include <mach/regs-irq.h> 31#endif 32#include <mach/irqs.h> 33#endif 34 35#include <asm/irq.h> 36 37#include <plat/pm.h> 38#include <mach/pm-core.h> 39 40/* for external use */ 41 42unsigned long s3c_pm_flags; 43 44/* The IRQ ext-int code goes here, it is too small to currently bother 45 * with its own file. */ 46 47unsigned long s3c_irqwake_intmask = 0xffffffffL; 48unsigned long s3c_irqwake_eintmask = 0xffffffffL; 49 50int s3c_irqext_wake(struct irq_data *data, unsigned int state) 51{ 52 unsigned long bit = 1L << IRQ_EINT_BIT(data->irq); 53 54 if (!(s3c_irqwake_eintallow & bit)) 55 return -ENOENT; 56 57 printk(KERN_INFO "wake %s for irq %d\n", 58 state ? "enabled" : "disabled", data->irq); 59 60 if (!state) 61 s3c_irqwake_eintmask |= bit; 62 else 63 s3c_irqwake_eintmask &= ~bit; 64 65 return 0; 66} 67 68void (*pm_cpu_prep)(void); 69int (*pm_cpu_sleep)(unsigned long); 70 71#define any_allowed(mask, allow) (((mask) & (allow)) != (allow)) 72 73/* s3c_pm_enter 74 * 75 * central control for sleep/resume process 76*/ 77 78static int s3c_pm_enter(suspend_state_t state) 79{ 80 int ret; 81 /* ensure the debug is initialised (if enabled) */ 82 83 s3c_pm_debug_init(); 84 85 S3C_PMDBG("%s(%d)\n", __func__, state); 86 87 if (pm_cpu_prep == NULL || pm_cpu_sleep == NULL) { 88 printk(KERN_ERR "%s: error: no cpu sleep function\n", __func__); 89 return -EINVAL; 90 } 91 92 /* check if we have anything to wake-up with... bad things seem 93 * to happen if you suspend with no wakeup (system will often 94 * require a full power-cycle) 95 */ 96 97 if (!of_have_populated_dt() && 98 !any_allowed(s3c_irqwake_intmask, s3c_irqwake_intallow) && 99 !any_allowed(s3c_irqwake_eintmask, s3c_irqwake_eintallow)) { 100 printk(KERN_ERR "%s: No wake-up sources!\n", __func__); 101 printk(KERN_ERR "%s: Aborting sleep\n", __func__); 102 return -EINVAL; 103 } 104 105 /* save all necessary core registers not covered by the drivers */ 106 107 if (!of_have_populated_dt()) { 108 samsung_pm_save_gpios(); 109 samsung_pm_saved_gpios(); 110 } 111 112 s3c_pm_save_uarts(); 113 s3c_pm_save_core(); 114 115 /* set the irq configuration for wake */ 116 117 s3c_pm_configure_extint(); 118 119 S3C_PMDBG("sleep: irq wakeup masks: %08lx,%08lx\n", 120 s3c_irqwake_intmask, s3c_irqwake_eintmask); 121 122 s3c_pm_arch_prepare_irqs(); 123 124 /* call cpu specific preparation */ 125 126 pm_cpu_prep(); 127 128 /* flush cache back to ram */ 129 130 flush_cache_all(); 131 132 s3c_pm_check_store(); 133 134 /* send the cpu to sleep... */ 135 136 s3c_pm_arch_stop_clocks(); 137 138 /* this will also act as our return point from when 139 * we resume as it saves its own register state and restores it 140 * during the resume. */ 141 142 ret = cpu_suspend(0, pm_cpu_sleep); 143 if (ret) 144 return ret; 145 146 /* restore the system state */ 147 148 s3c_pm_restore_core(); 149 s3c_pm_restore_uarts(); 150 151 if (!of_have_populated_dt()) { 152 samsung_pm_restore_gpios(); 153 s3c_pm_restored_gpios(); 154 } 155 156 s3c_pm_debug_init(); 157 158 /* check what irq (if any) restored the system */ 159 160 s3c_pm_arch_show_resume_irqs(); 161 162 S3C_PMDBG("%s: post sleep, preparing to return\n", __func__); 163 164 /* LEDs should now be 1110 */ 165 s3c_pm_debug_smdkled(1 << 1, 0); 166 167 s3c_pm_check_restore(); 168 169 /* ok, let's return from sleep */ 170 171 S3C_PMDBG("S3C PM Resume (post-restore)\n"); 172 return 0; 173} 174 175static int s3c_pm_prepare(void) 176{ 177 /* prepare check area if configured */ 178 179 s3c_pm_check_prepare(); 180 return 0; 181} 182 183static void s3c_pm_finish(void) 184{ 185 s3c_pm_check_cleanup(); 186} 187 188static const struct platform_suspend_ops s3c_pm_ops = { 189 .enter = s3c_pm_enter, 190 .prepare = s3c_pm_prepare, 191 .finish = s3c_pm_finish, 192 .valid = suspend_valid_only_mem, 193}; 194 195/* s3c_pm_init 196 * 197 * Attach the power management functions. This should be called 198 * from the board specific initialisation if the board supports 199 * it. 200*/ 201 202int __init s3c_pm_init(void) 203{ 204 printk("S3C Power Management, Copyright 2004 Simtec Electronics\n"); 205 206 suspend_set_ops(&s3c_pm_ops); 207 return 0; 208} 209