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 68/* s3c2410_pm_show_resume_irqs 69 * 70 * print any IRQs asserted at resume time (ie, we woke from) 71*/ 72static void __maybe_unused s3c_pm_show_resume_irqs(int start, 73 unsigned long which, 74 unsigned long mask) 75{ 76 int i; 77 78 which &= ~mask; 79 80 for (i = 0; i <= 31; i++) { 81 if (which & (1L<<i)) { 82 S3C_PMDBG("IRQ %d asserted at resume\n", start+i); 83 } 84 } 85} 86 87 88void (*pm_cpu_prep)(void); 89int (*pm_cpu_sleep)(unsigned long); 90 91#define any_allowed(mask, allow) (((mask) & (allow)) != (allow)) 92 93/* s3c_pm_enter 94 * 95 * central control for sleep/resume process 96*/ 97 98static int s3c_pm_enter(suspend_state_t state) 99{ 100 int ret; 101 /* ensure the debug is initialised (if enabled) */ 102 103 s3c_pm_debug_init(); 104 105 S3C_PMDBG("%s(%d)\n", __func__, state); 106 107 if (pm_cpu_prep == NULL || pm_cpu_sleep == NULL) { 108 printk(KERN_ERR "%s: error: no cpu sleep function\n", __func__); 109 return -EINVAL; 110 } 111 112 /* check if we have anything to wake-up with... bad things seem 113 * to happen if you suspend with no wakeup (system will often 114 * require a full power-cycle) 115 */ 116 117 if (!of_have_populated_dt() && 118 !any_allowed(s3c_irqwake_intmask, s3c_irqwake_intallow) && 119 !any_allowed(s3c_irqwake_eintmask, s3c_irqwake_eintallow)) { 120 printk(KERN_ERR "%s: No wake-up sources!\n", __func__); 121 printk(KERN_ERR "%s: Aborting sleep\n", __func__); 122 return -EINVAL; 123 } 124 125 /* save all necessary core registers not covered by the drivers */ 126 127 if (!of_have_populated_dt()) { 128 samsung_pm_save_gpios(); 129 samsung_pm_saved_gpios(); 130 } 131 132 s3c_pm_save_uarts(); 133 s3c_pm_save_core(); 134 135 /* set the irq configuration for wake */ 136 137 s3c_pm_configure_extint(); 138 139 S3C_PMDBG("sleep: irq wakeup masks: %08lx,%08lx\n", 140 s3c_irqwake_intmask, s3c_irqwake_eintmask); 141 142 s3c_pm_arch_prepare_irqs(); 143 144 /* call cpu specific preparation */ 145 146 pm_cpu_prep(); 147 148 /* flush cache back to ram */ 149 150 flush_cache_all(); 151 152 s3c_pm_check_store(); 153 154 /* send the cpu to sleep... */ 155 156 s3c_pm_arch_stop_clocks(); 157 158 /* this will also act as our return point from when 159 * we resume as it saves its own register state and restores it 160 * during the resume. */ 161 162 ret = cpu_suspend(0, pm_cpu_sleep); 163 if (ret) 164 return ret; 165 166 /* restore the system state */ 167 168 s3c_pm_restore_core(); 169 s3c_pm_restore_uarts(); 170 171 if (!of_have_populated_dt()) { 172 samsung_pm_restore_gpios(); 173 s3c_pm_restored_gpios(); 174 } 175 176 s3c_pm_debug_init(); 177 178 /* check what irq (if any) restored the system */ 179 180 s3c_pm_arch_show_resume_irqs(); 181 182 S3C_PMDBG("%s: post sleep, preparing to return\n", __func__); 183 184 /* LEDs should now be 1110 */ 185 s3c_pm_debug_smdkled(1 << 1, 0); 186 187 s3c_pm_check_restore(); 188 189 /* ok, let's return from sleep */ 190 191 S3C_PMDBG("S3C PM Resume (post-restore)\n"); 192 return 0; 193} 194 195static int s3c_pm_prepare(void) 196{ 197 /* prepare check area if configured */ 198 199 s3c_pm_check_prepare(); 200 return 0; 201} 202 203static void s3c_pm_finish(void) 204{ 205 s3c_pm_check_cleanup(); 206} 207 208static const struct platform_suspend_ops s3c_pm_ops = { 209 .enter = s3c_pm_enter, 210 .prepare = s3c_pm_prepare, 211 .finish = s3c_pm_finish, 212 .valid = suspend_valid_only_mem, 213}; 214 215/* s3c_pm_init 216 * 217 * Attach the power management functions. This should be called 218 * from the board specific initialisation if the board supports 219 * it. 220*/ 221 222int __init s3c_pm_init(void) 223{ 224 printk("S3C Power Management, Copyright 2004 Simtec Electronics\n"); 225 226 suspend_set_ops(&s3c_pm_ops); 227 return 0; 228} 229