1 /* 2 * cpuidle.h - a generic framework for CPU idle power management 3 * 4 * (C) 2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> 5 * Shaohua Li <shaohua.li@intel.com> 6 * Adam Belay <abelay@novell.com> 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/module.h> 17 #include <linux/kobject.h> 18 #include <linux/completion.h> 19 20 #define CPUIDLE_STATE_MAX 8 21 #define CPUIDLE_NAME_LEN 16 22 #define CPUIDLE_DESC_LEN 32 23 24 struct cpuidle_device; 25 26 27 /**************************** 28 * CPUIDLE DEVICE INTERFACE * 29 ****************************/ 30 31 struct cpuidle_state { 32 char name[CPUIDLE_NAME_LEN]; 33 char desc[CPUIDLE_DESC_LEN]; 34 void *driver_data; 35 36 unsigned int flags; 37 unsigned int exit_latency; /* in US */ 38 unsigned int power_usage; /* in mW */ 39 unsigned int target_residency; /* in US */ 40 41 unsigned long long usage; 42 unsigned long long time; /* in US */ 43 44 int (*enter) (struct cpuidle_device *dev, 45 struct cpuidle_state *state); 46 }; 47 48 /* Idle State Flags */ 49 #define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */ 50 #define CPUIDLE_FLAG_IGNORE (0x100) /* ignore during this idle period */ 51 52 #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000) 53 54 /** 55 * cpuidle_get_statedata - retrieves private driver state data 56 * @state: the state 57 */ cpuidle_get_statedata(struct cpuidle_state * state)58static inline void * cpuidle_get_statedata(struct cpuidle_state *state) 59 { 60 return state->driver_data; 61 } 62 63 /** 64 * cpuidle_set_statedata - stores private driver state data 65 * @state: the state 66 * @data: the private data 67 */ 68 static inline void cpuidle_set_statedata(struct cpuidle_state * state,void * data)69cpuidle_set_statedata(struct cpuidle_state *state, void *data) 70 { 71 state->driver_data = data; 72 } 73 74 struct cpuidle_state_kobj { 75 struct cpuidle_state *state; 76 struct completion kobj_unregister; 77 struct kobject kobj; 78 }; 79 80 struct cpuidle_device { 81 unsigned int registered:1; 82 unsigned int enabled:1; 83 unsigned int power_specified:1; 84 unsigned int cpu; 85 86 int last_residency; 87 int state_count; 88 struct cpuidle_state states[CPUIDLE_STATE_MAX]; 89 struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX]; 90 struct cpuidle_state *last_state; 91 92 struct list_head device_list; 93 struct kobject kobj; 94 struct completion kobj_unregister; 95 void *governor_data; 96 struct cpuidle_state *safe_state; 97 98 int (*prepare) (struct cpuidle_device *dev); 99 }; 100 101 DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices); 102 103 /** 104 * cpuidle_get_last_residency - retrieves the last state's residency time 105 * @dev: the target CPU 106 * 107 * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_VALID isn't set 108 */ cpuidle_get_last_residency(struct cpuidle_device * dev)109static inline int cpuidle_get_last_residency(struct cpuidle_device *dev) 110 { 111 return dev->last_residency; 112 } 113 114 115 /**************************** 116 * CPUIDLE DRIVER INTERFACE * 117 ****************************/ 118 119 struct cpuidle_driver { 120 char name[CPUIDLE_NAME_LEN]; 121 struct module *owner; 122 }; 123 124 #ifdef CONFIG_CPU_IDLE 125 126 extern int cpuidle_register_driver(struct cpuidle_driver *drv); 127 struct cpuidle_driver *cpuidle_get_driver(void); 128 extern void cpuidle_unregister_driver(struct cpuidle_driver *drv); 129 extern int cpuidle_register_device(struct cpuidle_device *dev); 130 extern void cpuidle_unregister_device(struct cpuidle_device *dev); 131 132 extern void cpuidle_pause_and_lock(void); 133 extern void cpuidle_resume_and_unlock(void); 134 extern int cpuidle_enable_device(struct cpuidle_device *dev); 135 extern void cpuidle_disable_device(struct cpuidle_device *dev); 136 137 #else 138 cpuidle_register_driver(struct cpuidle_driver * drv)139static inline int cpuidle_register_driver(struct cpuidle_driver *drv) 140 {return -ENODEV; } cpuidle_get_driver(void)141static inline struct cpuidle_driver *cpuidle_get_driver(void) {return NULL; } cpuidle_unregister_driver(struct cpuidle_driver * drv)142static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { } cpuidle_register_device(struct cpuidle_device * dev)143static inline int cpuidle_register_device(struct cpuidle_device *dev) 144 {return -ENODEV; } cpuidle_unregister_device(struct cpuidle_device * dev)145static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { } 146 cpuidle_pause_and_lock(void)147static inline void cpuidle_pause_and_lock(void) { } cpuidle_resume_and_unlock(void)148static inline void cpuidle_resume_and_unlock(void) { } cpuidle_enable_device(struct cpuidle_device * dev)149static inline int cpuidle_enable_device(struct cpuidle_device *dev) 150 {return -ENODEV; } cpuidle_disable_device(struct cpuidle_device * dev)151static inline void cpuidle_disable_device(struct cpuidle_device *dev) { } 152 153 #endif 154 155 /****************************** 156 * CPUIDLE GOVERNOR INTERFACE * 157 ******************************/ 158 159 struct cpuidle_governor { 160 char name[CPUIDLE_NAME_LEN]; 161 struct list_head governor_list; 162 unsigned int rating; 163 164 int (*enable) (struct cpuidle_device *dev); 165 void (*disable) (struct cpuidle_device *dev); 166 167 int (*select) (struct cpuidle_device *dev); 168 void (*reflect) (struct cpuidle_device *dev); 169 170 struct module *owner; 171 }; 172 173 #ifdef CONFIG_CPU_IDLE 174 175 extern int cpuidle_register_governor(struct cpuidle_governor *gov); 176 extern void cpuidle_unregister_governor(struct cpuidle_governor *gov); 177 178 #else 179 cpuidle_register_governor(struct cpuidle_governor * gov)180static inline int cpuidle_register_governor(struct cpuidle_governor *gov) 181 {return 0;} cpuidle_unregister_governor(struct cpuidle_governor * gov)182static inline void cpuidle_unregister_governor(struct cpuidle_governor *gov) { } 183 184 #endif 185 186 #ifdef CONFIG_ARCH_HAS_CPU_RELAX 187 #define CPUIDLE_DRIVER_STATE_START 1 188 #else 189 #define CPUIDLE_DRIVER_STATE_START 0 190 #endif 191 192 #endif /* _LINUX_CPUIDLE_H */ 193