1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * arch/sh/kernel/cpu/shmobile/cpuidle.c 4 * 5 * Cpuidle support code for SuperH Mobile 6 * 7 * Copyright (C) 2009 Magnus Damm 8 */ 9 #include <linux/init.h> 10 #include <linux/kernel.h> 11 #include <linux/io.h> 12 #include <linux/suspend.h> 13 #include <linux/cpuidle.h> 14 #include <linux/export.h> 15 #include <asm/suspend.h> 16 #include <linux/uaccess.h> 17 18 static unsigned long cpuidle_mode[] = { 19 SUSP_SH_SLEEP, /* regular sleep mode */ 20 SUSP_SH_SLEEP | SUSP_SH_SF, /* sleep mode + self refresh */ 21 SUSP_SH_STANDBY | SUSP_SH_SF, /* software standby mode + self refresh */ 22 }; 23 24 static int cpuidle_sleep_enter(struct cpuidle_device *dev, 25 struct cpuidle_driver *drv, 26 int index) 27 { 28 unsigned long allowed_mode = SUSP_SH_SLEEP; 29 int requested_state = index; 30 int allowed_state; 31 int k; 32 33 /* convert allowed mode to allowed state */ 34 for (k = ARRAY_SIZE(cpuidle_mode) - 1; k > 0; k--) 35 if (cpuidle_mode[k] == allowed_mode) 36 break; 37 38 allowed_state = k; 39 40 /* take the following into account for sleep mode selection: 41 * - allowed_state: best mode allowed by hardware (clock deps) 42 * - requested_state: best mode allowed by software (latencies) 43 */ 44 k = min_t(int, allowed_state, requested_state); 45 46 sh_mobile_call_standby(cpuidle_mode[k]); 47 48 return k; 49 } 50 51 static struct cpuidle_driver cpuidle_driver = { 52 .name = "sh_idle", 53 .owner = THIS_MODULE, 54 .states = { 55 { 56 .exit_latency = 1, 57 .target_residency = 1 * 2, 58 .power_usage = 3, 59 .enter = cpuidle_sleep_enter, 60 .name = "C1", 61 .desc = "SuperH Sleep Mode", 62 }, 63 { 64 .exit_latency = 100, 65 .target_residency = 1 * 2, 66 .power_usage = 1, 67 .enter = cpuidle_sleep_enter, 68 .name = "C2", 69 .desc = "SuperH Sleep Mode [SF]", 70 .flags = CPUIDLE_FLAG_UNUSABLE, 71 }, 72 { 73 .exit_latency = 2300, 74 .target_residency = 1 * 2, 75 .power_usage = 1, 76 .enter = cpuidle_sleep_enter, 77 .name = "C3", 78 .desc = "SuperH Mobile Standby Mode [SF]", 79 .flags = CPUIDLE_FLAG_UNUSABLE, 80 }, 81 }, 82 .safe_state_index = 0, 83 .state_count = 3, 84 }; 85 86 int __init sh_mobile_setup_cpuidle(void) 87 { 88 if (sh_mobile_sleep_supported & SUSP_SH_SF) 89 cpuidle_driver.states[1].flags = CPUIDLE_FLAG_NONE; 90 91 if (sh_mobile_sleep_supported & SUSP_SH_STANDBY) 92 cpuidle_driver.states[2].flags = CPUIDLE_FLAG_NONE; 93 94 return cpuidle_register(&cpuidle_driver, NULL); 95 } 96