1 /* 2 * cpuidle.h - a generic framework for CPU idle power management 3 * 4 * (C) 2007 Venkatesh Pallipadi <[email protected]> 5 * Shaohua Li <[email protected]> 6 * Adam Belay <[email protected]> 7 * 8 * This code is licenced under the GPL. 9 */ 10 11 #ifndef _LINUX_CPUIDLE_H 12 #define _LINUX_CPUIDLE_H 13 14 #include <linux/percpu.h> 15 #include <linux/list.h> 16 #include <linux/kobject.h> 17 #include <linux/completion.h> 18 #include <linux/hrtimer.h> 19 20 #define CPUIDLE_STATE_MAX 8 21 #define CPUIDLE_NAME_LEN 16 22 #define CPUIDLE_DESC_LEN 32 23 24 struct module; 25 26 struct cpuidle_device; 27 struct cpuidle_driver; 28 29 30 /**************************** 31 * CPUIDLE DEVICE INTERFACE * 32 ****************************/ 33 34 struct cpuidle_state_usage { 35 unsigned long long disable; 36 unsigned long long usage; 37 unsigned long long time; /* in US */ 38 }; 39 40 struct cpuidle_state { 41 char name[CPUIDLE_NAME_LEN]; 42 char desc[CPUIDLE_DESC_LEN]; 43 44 unsigned int flags; 45 unsigned int exit_latency; /* in US */ 46 int power_usage; /* in mW */ 47 unsigned int target_residency; /* in US */ 48 bool disabled; /* disabled on all CPUs */ 49 50 int (*enter) (struct cpuidle_device *dev, 51 struct cpuidle_driver *drv, 52 int index); 53 54 int (*enter_dead) (struct cpuidle_device *dev, int index); 55 }; 56 57 /* Idle State Flags */ 58 #define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */ 59 #define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */ 60 61 #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000) 62 63 struct cpuidle_device { 64 unsigned int registered:1; 65 unsigned int enabled:1; 66 unsigned int cpu; 67 68 int last_residency; 69 int state_count; 70 struct cpuidle_state_usage states_usage[CPUIDLE_STATE_MAX]; 71 struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX]; 72 struct cpuidle_driver_kobj *kobj_driver; 73 struct list_head device_list; 74 struct kobject kobj; 75 struct completion kobj_unregister; 76 77 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED 78 int safe_state_index; 79 cpumask_t coupled_cpus; 80 struct cpuidle_coupled *coupled; 81 #endif 82 }; 83 84 DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices); 85 86 /** 87 * cpuidle_get_last_residency - retrieves the last state's residency time 88 * @dev: the target CPU 89 * 90 * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_VALID isn't set 91 */ 92 static inline int cpuidle_get_last_residency(struct cpuidle_device *dev) 93 { 94 return dev->last_residency; 95 } 96 97 98 /**************************** 99 * CPUIDLE DRIVER INTERFACE * 100 ****************************/ 101 102 struct cpuidle_driver { 103 const char *name; 104 struct module *owner; 105 int refcnt; 106 107 /* set to 1 to use the core cpuidle time keeping (for all states). */ 108 unsigned int en_core_tk_irqen:1; 109 /* states array must be ordered in decreasing power consumption */ 110 struct cpuidle_state states[CPUIDLE_STATE_MAX]; 111 int state_count; 112 int safe_state_index; 113 }; 114 115 #ifdef CONFIG_CPU_IDLE 116 extern void disable_cpuidle(void); 117 extern int cpuidle_idle_call(void); 118 extern int cpuidle_register_driver(struct cpuidle_driver *drv); 119 extern struct cpuidle_driver *cpuidle_get_driver(void); 120 extern struct cpuidle_driver *cpuidle_driver_ref(void); 121 extern void cpuidle_driver_unref(void); 122 extern void cpuidle_unregister_driver(struct cpuidle_driver *drv); 123 extern int cpuidle_register_device(struct cpuidle_device *dev); 124 extern void cpuidle_unregister_device(struct cpuidle_device *dev); 125 126 extern void cpuidle_pause_and_lock(void); 127 extern void cpuidle_resume_and_unlock(void); 128 extern void cpuidle_pause(void); 129 extern void cpuidle_resume(void); 130 extern int cpuidle_enable_device(struct cpuidle_device *dev); 131 extern void cpuidle_disable_device(struct cpuidle_device *dev); 132 extern int cpuidle_wrap_enter(struct cpuidle_device *dev, 133 struct cpuidle_driver *drv, int index, 134 int (*enter)(struct cpuidle_device *dev, 135 struct cpuidle_driver *drv, int index)); 136 extern int cpuidle_play_dead(void); 137 138 extern struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev); 139 extern int cpuidle_register_cpu_driver(struct cpuidle_driver *drv, int cpu); 140 extern void cpuidle_unregister_cpu_driver(struct cpuidle_driver *drv, int cpu); 141 142 #else 143 static inline void disable_cpuidle(void) { } 144 static inline int cpuidle_idle_call(void) { return -ENODEV; } 145 static inline int cpuidle_register_driver(struct cpuidle_driver *drv) 146 {return -ENODEV; } 147 static inline struct cpuidle_driver *cpuidle_get_driver(void) {return NULL; } 148 static inline struct cpuidle_driver *cpuidle_driver_ref(void) {return NULL; } 149 static inline void cpuidle_driver_unref(void) {} 150 static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { } 151 static inline int cpuidle_register_device(struct cpuidle_device *dev) 152 {return -ENODEV; } 153 static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { } 154 155 static inline void cpuidle_pause_and_lock(void) { } 156 static inline void cpuidle_resume_and_unlock(void) { } 157 static inline void cpuidle_pause(void) { } 158 static inline void cpuidle_resume(void) { } 159 static inline int cpuidle_enable_device(struct cpuidle_device *dev) 160 {return -ENODEV; } 161 static inline void cpuidle_disable_device(struct cpuidle_device *dev) { } 162 static inline int cpuidle_wrap_enter(struct cpuidle_device *dev, 163 struct cpuidle_driver *drv, int index, 164 int (*enter)(struct cpuidle_device *dev, 165 struct cpuidle_driver *drv, int index)) 166 { return -ENODEV; } 167 static inline int cpuidle_play_dead(void) {return -ENODEV; } 168 #endif 169 170 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED 171 void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a); 172 #else 173 static inline void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a) 174 { 175 } 176 #endif 177 178 /****************************** 179 * CPUIDLE GOVERNOR INTERFACE * 180 ******************************/ 181 182 struct cpuidle_governor { 183 char name[CPUIDLE_NAME_LEN]; 184 struct list_head governor_list; 185 unsigned int rating; 186 187 int (*enable) (struct cpuidle_driver *drv, 188 struct cpuidle_device *dev); 189 void (*disable) (struct cpuidle_driver *drv, 190 struct cpuidle_device *dev); 191 192 int (*select) (struct cpuidle_driver *drv, 193 struct cpuidle_device *dev); 194 void (*reflect) (struct cpuidle_device *dev, int index); 195 196 struct module *owner; 197 }; 198 199 #ifdef CONFIG_CPU_IDLE 200 201 extern int cpuidle_register_governor(struct cpuidle_governor *gov); 202 extern void cpuidle_unregister_governor(struct cpuidle_governor *gov); 203 204 #else 205 206 static inline int cpuidle_register_governor(struct cpuidle_governor *gov) 207 {return 0;} 208 static inline void cpuidle_unregister_governor(struct cpuidle_governor *gov) { } 209 210 #endif 211 212 #ifdef CONFIG_ARCH_HAS_CPU_RELAX 213 #define CPUIDLE_DRIVER_STATE_START 1 214 #else 215 #define CPUIDLE_DRIVER_STATE_START 0 216 #endif 217 218 #endif /* _LINUX_CPUIDLE_H */ 219