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/hrtimer.h> 17 18 #define CPUIDLE_STATE_MAX 10 19 #define CPUIDLE_NAME_LEN 16 20 #define CPUIDLE_DESC_LEN 32 21 22 struct module; 23 24 struct cpuidle_device; 25 struct cpuidle_driver; 26 27 28 /**************************** 29 * CPUIDLE DEVICE INTERFACE * 30 ****************************/ 31 32 struct cpuidle_state_usage { 33 unsigned long long disable; 34 unsigned long long usage; 35 unsigned long long time; /* in US */ 36 }; 37 38 struct cpuidle_state { 39 char name[CPUIDLE_NAME_LEN]; 40 char desc[CPUIDLE_DESC_LEN]; 41 42 unsigned int flags; 43 unsigned int exit_latency; /* in US */ 44 int power_usage; /* in mW */ 45 unsigned int target_residency; /* in US */ 46 bool disabled; /* disabled on all CPUs */ 47 48 int (*enter) (struct cpuidle_device *dev, 49 struct cpuidle_driver *drv, 50 int index); 51 52 int (*enter_dead) (struct cpuidle_device *dev, int index); 53 }; 54 55 /* Idle State Flags */ 56 #define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */ 57 #define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */ 58 #define CPUIDLE_FLAG_TIMER_STOP (0x04) /* timer is stopped on this state */ 59 60 #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000) 61 62 struct cpuidle_device_kobj; 63 struct cpuidle_state_kobj; 64 struct cpuidle_driver_kobj; 65 66 struct cpuidle_device { 67 unsigned int registered:1; 68 unsigned int enabled:1; 69 unsigned int cpu; 70 71 int last_residency; 72 int state_count; 73 struct cpuidle_state_usage states_usage[CPUIDLE_STATE_MAX]; 74 struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX]; 75 struct cpuidle_driver_kobj *kobj_driver; 76 struct cpuidle_device_kobj *kobj_dev; 77 struct list_head device_list; 78 79 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED 80 int safe_state_index; 81 cpumask_t coupled_cpus; 82 struct cpuidle_coupled *coupled; 83 #endif 84 }; 85 86 DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices); 87 88 /** 89 * cpuidle_get_last_residency - retrieves the last state's residency time 90 * @dev: the target CPU 91 * 92 * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_VALID isn't set 93 */ 94 static inline int cpuidle_get_last_residency(struct cpuidle_device *dev) 95 { 96 return dev->last_residency; 97 } 98 99 100 /**************************** 101 * CPUIDLE DRIVER INTERFACE * 102 ****************************/ 103 104 struct cpuidle_driver { 105 const char *name; 106 struct module *owner; 107 int refcnt; 108 109 /* used by the cpuidle framework to setup the broadcast timer */ 110 unsigned int bctimer:1; 111 /* states array must be ordered in decreasing power consumption */ 112 struct cpuidle_state states[CPUIDLE_STATE_MAX]; 113 int state_count; 114 int safe_state_index; 115 116 /* the driver handles the cpus in cpumask */ 117 struct cpumask *cpumask; 118 }; 119 120 #ifdef CONFIG_CPU_IDLE 121 extern void disable_cpuidle(void); 122 extern int cpuidle_idle_call(void); 123 extern int cpuidle_register_driver(struct cpuidle_driver *drv); 124 extern struct cpuidle_driver *cpuidle_get_driver(void); 125 extern struct cpuidle_driver *cpuidle_driver_ref(void); 126 extern void cpuidle_driver_unref(void); 127 extern void cpuidle_unregister_driver(struct cpuidle_driver *drv); 128 extern int cpuidle_register_device(struct cpuidle_device *dev); 129 extern void cpuidle_unregister_device(struct cpuidle_device *dev); 130 extern int cpuidle_register(struct cpuidle_driver *drv, 131 const struct cpumask *const coupled_cpus); 132 extern void cpuidle_unregister(struct cpuidle_driver *drv); 133 extern void cpuidle_pause_and_lock(void); 134 extern void cpuidle_resume_and_unlock(void); 135 extern void cpuidle_pause(void); 136 extern void cpuidle_resume(void); 137 extern int cpuidle_enable_device(struct cpuidle_device *dev); 138 extern void cpuidle_disable_device(struct cpuidle_device *dev); 139 extern int cpuidle_play_dead(void); 140 141 extern struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev); 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 static inline int cpuidle_register(struct cpuidle_driver *drv, 155 const struct cpumask *const coupled_cpus) 156 {return -ENODEV; } 157 static inline void cpuidle_unregister(struct cpuidle_driver *drv) { } 158 static inline void cpuidle_pause_and_lock(void) { } 159 static inline void cpuidle_resume_and_unlock(void) { } 160 static inline void cpuidle_pause(void) { } 161 static inline void cpuidle_resume(void) { } 162 static inline int cpuidle_enable_device(struct cpuidle_device *dev) 163 {return -ENODEV; } 164 static inline void cpuidle_disable_device(struct cpuidle_device *dev) { } 165 static inline int cpuidle_play_dead(void) {return -ENODEV; } 166 #endif 167 168 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED 169 void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a); 170 #else 171 static inline void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a) 172 { 173 } 174 #endif 175 176 /****************************** 177 * CPUIDLE GOVERNOR INTERFACE * 178 ******************************/ 179 180 struct cpuidle_governor { 181 char name[CPUIDLE_NAME_LEN]; 182 struct list_head governor_list; 183 unsigned int rating; 184 185 int (*enable) (struct cpuidle_driver *drv, 186 struct cpuidle_device *dev); 187 void (*disable) (struct cpuidle_driver *drv, 188 struct cpuidle_device *dev); 189 190 int (*select) (struct cpuidle_driver *drv, 191 struct cpuidle_device *dev); 192 void (*reflect) (struct cpuidle_device *dev, int index); 193 194 struct module *owner; 195 }; 196 197 #ifdef CONFIG_CPU_IDLE 198 extern int cpuidle_register_governor(struct cpuidle_governor *gov); 199 #else 200 static inline int cpuidle_register_governor(struct cpuidle_governor *gov) 201 {return 0;} 202 #endif 203 204 #ifdef CONFIG_ARCH_HAS_CPU_RELAX 205 #define CPUIDLE_DRIVER_STATE_START 1 206 #else 207 #define CPUIDLE_DRIVER_STATE_START 0 208 #endif 209 210 #endif /* _LINUX_CPUIDLE_H */ 211