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 void *driver_data; 36 37 unsigned long long usage; 38 unsigned long long time; /* in US */ 39 }; 40 41 struct cpuidle_state { 42 char name[CPUIDLE_NAME_LEN]; 43 char desc[CPUIDLE_DESC_LEN]; 44 45 unsigned int flags; 46 unsigned int exit_latency; /* in US */ 47 int power_usage; /* in mW */ 48 unsigned int target_residency; /* in US */ 49 unsigned int disable; 50 51 int (*enter) (struct cpuidle_device *dev, 52 struct cpuidle_driver *drv, 53 int index); 54 55 int (*enter_dead) (struct cpuidle_device *dev, int index); 56 }; 57 58 /* Idle State Flags */ 59 #define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */ 60 61 #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000) 62 63 /** 64 * cpuidle_get_statedata - retrieves private driver state data 65 * @st_usage: the state usage statistics 66 */ 67 static inline void *cpuidle_get_statedata(struct cpuidle_state_usage *st_usage) 68 { 69 return st_usage->driver_data; 70 } 71 72 /** 73 * cpuidle_set_statedata - stores private driver state data 74 * @st_usage: the state usage statistics 75 * @data: the private data 76 */ 77 static inline void 78 cpuidle_set_statedata(struct cpuidle_state_usage *st_usage, void *data) 79 { 80 st_usage->driver_data = data; 81 } 82 83 struct cpuidle_state_kobj { 84 struct cpuidle_state *state; 85 struct cpuidle_state_usage *state_usage; 86 struct completion kobj_unregister; 87 struct kobject kobj; 88 }; 89 90 struct cpuidle_device { 91 unsigned int registered:1; 92 unsigned int enabled:1; 93 unsigned int cpu; 94 95 int last_residency; 96 int state_count; 97 struct cpuidle_state_usage states_usage[CPUIDLE_STATE_MAX]; 98 struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX]; 99 100 struct list_head device_list; 101 struct kobject kobj; 102 struct completion kobj_unregister; 103 }; 104 105 DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices); 106 107 /** 108 * cpuidle_get_last_residency - retrieves the last state's residency time 109 * @dev: the target CPU 110 * 111 * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_VALID isn't set 112 */ 113 static inline int cpuidle_get_last_residency(struct cpuidle_device *dev) 114 { 115 return dev->last_residency; 116 } 117 118 119 /**************************** 120 * CPUIDLE DRIVER INTERFACE * 121 ****************************/ 122 123 struct cpuidle_driver { 124 const char *name; 125 struct module *owner; 126 127 unsigned int power_specified:1; 128 /* set to 1 to use the core cpuidle time keeping (for all states). */ 129 unsigned int en_core_tk_irqen:1; 130 struct cpuidle_state states[CPUIDLE_STATE_MAX]; 131 int state_count; 132 int safe_state_index; 133 }; 134 135 #ifdef CONFIG_CPU_IDLE 136 extern void disable_cpuidle(void); 137 extern int cpuidle_idle_call(void); 138 extern int cpuidle_register_driver(struct cpuidle_driver *drv); 139 struct cpuidle_driver *cpuidle_get_driver(void); 140 extern void cpuidle_unregister_driver(struct cpuidle_driver *drv); 141 extern int cpuidle_register_device(struct cpuidle_device *dev); 142 extern void cpuidle_unregister_device(struct cpuidle_device *dev); 143 144 extern void cpuidle_pause_and_lock(void); 145 extern void cpuidle_resume_and_unlock(void); 146 extern int cpuidle_enable_device(struct cpuidle_device *dev); 147 extern void cpuidle_disable_device(struct cpuidle_device *dev); 148 extern int cpuidle_wrap_enter(struct cpuidle_device *dev, 149 struct cpuidle_driver *drv, int index, 150 int (*enter)(struct cpuidle_device *dev, 151 struct cpuidle_driver *drv, int index)); 152 extern int cpuidle_play_dead(void); 153 154 #else 155 static inline void disable_cpuidle(void) { } 156 static inline int cpuidle_idle_call(void) { return -ENODEV; } 157 static inline int cpuidle_register_driver(struct cpuidle_driver *drv) 158 {return -ENODEV; } 159 static inline struct cpuidle_driver *cpuidle_get_driver(void) {return NULL; } 160 static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { } 161 static inline int cpuidle_register_device(struct cpuidle_device *dev) 162 {return -ENODEV; } 163 static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { } 164 165 static inline void cpuidle_pause_and_lock(void) { } 166 static inline void cpuidle_resume_and_unlock(void) { } 167 static inline int cpuidle_enable_device(struct cpuidle_device *dev) 168 {return -ENODEV; } 169 static inline void cpuidle_disable_device(struct cpuidle_device *dev) { } 170 static inline int cpuidle_wrap_enter(struct cpuidle_device *dev, 171 struct cpuidle_driver *drv, int index, 172 int (*enter)(struct cpuidle_device *dev, 173 struct cpuidle_driver *drv, int index)) 174 { return -ENODEV; } 175 static inline int cpuidle_play_dead(void) {return -ENODEV; } 176 177 #endif 178 179 /****************************** 180 * CPUIDLE GOVERNOR INTERFACE * 181 ******************************/ 182 183 struct cpuidle_governor { 184 char name[CPUIDLE_NAME_LEN]; 185 struct list_head governor_list; 186 unsigned int rating; 187 188 int (*enable) (struct cpuidle_driver *drv, 189 struct cpuidle_device *dev); 190 void (*disable) (struct cpuidle_driver *drv, 191 struct cpuidle_device *dev); 192 193 int (*select) (struct cpuidle_driver *drv, 194 struct cpuidle_device *dev); 195 void (*reflect) (struct cpuidle_device *dev, int index); 196 197 struct module *owner; 198 }; 199 200 #ifdef CONFIG_CPU_IDLE 201 202 extern int cpuidle_register_governor(struct cpuidle_governor *gov); 203 extern void cpuidle_unregister_governor(struct cpuidle_governor *gov); 204 205 #ifdef CONFIG_INTEL_IDLE 206 extern int intel_idle_cpu_init(int cpu); 207 #else 208 static inline int intel_idle_cpu_init(int cpu) { return -1; } 209 #endif 210 211 #else 212 static inline int intel_idle_cpu_init(int cpu) { return -1; } 213 214 static inline int cpuidle_register_governor(struct cpuidle_governor *gov) 215 {return 0;} 216 static inline void cpuidle_unregister_governor(struct cpuidle_governor *gov) { } 217 218 #endif 219 220 #ifdef CONFIG_ARCH_HAS_CPU_RELAX 221 #define CPUIDLE_DRIVER_STATE_START 1 222 #else 223 #define CPUIDLE_DRIVER_STATE_START 0 224 #endif 225 226 #endif /* _LINUX_CPUIDLE_H */ 227