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 <linux/export.h> 18 #include <asm/suspend.h> 19 #include <asm/uaccess.h> 20 21 static 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 27 static int cpuidle_sleep_enter(struct cpuidle_device *dev, 28 struct cpuidle_driver *drv, 29 int index) 30 { 31 unsigned long allowed_mode = SUSP_SH_SLEEP; 32 int requested_state = index; 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 sh_mobile_call_standby(cpuidle_mode[k]); 50 51 return k; 52 } 53 54 static struct cpuidle_device cpuidle_dev; 55 static struct cpuidle_driver cpuidle_driver = { 56 .name = "sh_idle", 57 .owner = THIS_MODULE, 58 .en_core_tk_irqen = 1, 59 }; 60 61 void sh_mobile_setup_cpuidle(void) 62 { 63 struct cpuidle_device *dev = &cpuidle_dev; 64 struct cpuidle_driver *drv = &cpuidle_driver; 65 struct cpuidle_state *state; 66 int i; 67 68 i = CPUIDLE_DRIVER_STATE_START; 69 70 state = &drv->states[i++]; 71 snprintf(state->name, CPUIDLE_NAME_LEN, "C1"); 72 strncpy(state->desc, "SuperH Sleep Mode", CPUIDLE_DESC_LEN); 73 state->exit_latency = 1; 74 state->target_residency = 1 * 2; 75 state->power_usage = 3; 76 state->flags = 0; 77 state->flags |= CPUIDLE_FLAG_TIME_VALID; 78 state->enter = cpuidle_sleep_enter; 79 80 drv->safe_state_index = i-1; 81 82 if (sh_mobile_sleep_supported & SUSP_SH_SF) { 83 state = &drv->states[i++]; 84 snprintf(state->name, CPUIDLE_NAME_LEN, "C2"); 85 strncpy(state->desc, "SuperH Sleep Mode [SF]", 86 CPUIDLE_DESC_LEN); 87 state->exit_latency = 100; 88 state->target_residency = 1 * 2; 89 state->power_usage = 1; 90 state->flags = 0; 91 state->flags |= CPUIDLE_FLAG_TIME_VALID; 92 state->enter = cpuidle_sleep_enter; 93 } 94 95 if (sh_mobile_sleep_supported & SUSP_SH_STANDBY) { 96 state = &drv->states[i++]; 97 snprintf(state->name, CPUIDLE_NAME_LEN, "C3"); 98 strncpy(state->desc, "SuperH Mobile Standby Mode [SF]", 99 CPUIDLE_DESC_LEN); 100 state->exit_latency = 2300; 101 state->target_residency = 1 * 2; 102 state->power_usage = 1; 103 state->flags = 0; 104 state->flags |= CPUIDLE_FLAG_TIME_VALID; 105 state->enter = cpuidle_sleep_enter; 106 } 107 108 drv->state_count = i; 109 dev->state_count = i; 110 111 cpuidle_register_driver(&cpuidle_driver); 112 113 cpuidle_register_device(dev); 114 } 115