1/* 2 * arch/sh/kernel/cpu/shmobile/cpuidle.c 3 * 4 * Cpuidle support code for SuperH Mobile 5 * 6 * Copyright (C) 2009 Magnus Damm 7 * 8 * This file is subject to the terms and conditions of the GNU General Public 9 * License. See the file "COPYING" in the main directory of this archive 10 * for more details. 11 */ 12#include <linux/init.h> 13#include <linux/kernel.h> 14#include <linux/io.h> 15#include <linux/suspend.h> 16#include <linux/cpuidle.h> 17#include <asm/suspend.h> 18#include <asm/uaccess.h> 19#include <asm/hwblk.h> 20 21static unsigned long cpuidle_mode[] = { 22 SUSP_SH_SLEEP, /* regular sleep mode */ 23 SUSP_SH_SLEEP | SUSP_SH_SF, /* sleep mode + self refresh */ 24 SUSP_SH_STANDBY | SUSP_SH_SF, /* software standby mode + self refresh */ 25}; 26 27static int cpuidle_sleep_enter(struct cpuidle_device *dev, 28 struct cpuidle_state *state) 29{ 30 unsigned long allowed_mode = arch_hwblk_sleep_mode(); 31 ktime_t before, after; 32 int requested_state = state - &dev->states[0]; 33 int allowed_state; 34 int k; 35 36 /* convert allowed mode to allowed state */ 37 for (k = ARRAY_SIZE(cpuidle_mode) - 1; k > 0; k--) 38 if (cpuidle_mode[k] == allowed_mode) 39 break; 40 41 allowed_state = k; 42 43 /* take the following into account for sleep mode selection: 44 * - allowed_state: best mode allowed by hardware (clock deps) 45 * - requested_state: best mode allowed by software (latencies) 46 */ 47 k = min_t(int, allowed_state, requested_state); 48 49 dev->last_state = &dev->states[k]; 50 before = ktime_get(); 51 sh_mobile_call_standby(cpuidle_mode[k]); 52 after = ktime_get(); 53 return ktime_to_ns(ktime_sub(after, before)) >> 10; 54} 55 56static struct cpuidle_device cpuidle_dev; 57static struct cpuidle_driver cpuidle_driver = { 58 .name = "sh_idle", 59 .owner = THIS_MODULE, 60}; 61 62void sh_mobile_setup_cpuidle(void) 63{ 64 struct cpuidle_device *dev = &cpuidle_dev; 65 struct cpuidle_state *state; 66 int i; 67 68 cpuidle_register_driver(&cpuidle_driver); 69 70 for (i = 0; i < CPUIDLE_STATE_MAX; i++) { 71 dev->states[i].name[0] = '\0'; 72 dev->states[i].desc[0] = '\0'; 73 } 74 75 i = CPUIDLE_DRIVER_STATE_START; 76 77 state = &dev->states[i++]; 78 snprintf(state->name, CPUIDLE_NAME_LEN, "C0"); 79 strncpy(state->desc, "SuperH Sleep Mode", CPUIDLE_DESC_LEN); 80 state->exit_latency = 1; 81 state->target_residency = 1 * 2; 82 state->power_usage = 3; 83 state->flags = 0; 84 state->flags |= CPUIDLE_FLAG_SHALLOW; 85 state->flags |= CPUIDLE_FLAG_TIME_VALID; 86 state->enter = cpuidle_sleep_enter; 87 88 dev->safe_state = state; 89 90 if (sh_mobile_sleep_supported & SUSP_SH_SF) { 91 state = &dev->states[i++]; 92 snprintf(state->name, CPUIDLE_NAME_LEN, "C1"); 93 strncpy(state->desc, "SuperH Sleep Mode [SF]", 94 CPUIDLE_DESC_LEN); 95 state->exit_latency = 100; 96 state->target_residency = 1 * 2; 97 state->power_usage = 1; 98 state->flags = 0; 99 state->flags |= CPUIDLE_FLAG_TIME_VALID; 100 state->enter = cpuidle_sleep_enter; 101 } 102 103 if (sh_mobile_sleep_supported & SUSP_SH_STANDBY) { 104 state = &dev->states[i++]; 105 snprintf(state->name, CPUIDLE_NAME_LEN, "C2"); 106 strncpy(state->desc, "SuperH Mobile Standby Mode [SF]", 107 CPUIDLE_DESC_LEN); 108 state->exit_latency = 2300; 109 state->target_residency = 1 * 2; 110 state->power_usage = 1; 111 state->flags = 0; 112 state->flags |= CPUIDLE_FLAG_TIME_VALID; 113 state->enter = cpuidle_sleep_enter; 114 } 115 116 dev->state_count = i; 117 118 cpuidle_register_device(dev); 119} 120