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_COUPLED (0x02) /* state applies to multiple cpus */ 57 #define CPUIDLE_FLAG_TIMER_STOP (0x04) /* timer is stopped on this state */ 58 59 #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000) 60 61 struct cpuidle_device_kobj; 62 struct cpuidle_state_kobj; 63 struct cpuidle_driver_kobj; 64 65 struct cpuidle_device { 66 unsigned int registered:1; 67 unsigned int enabled:1; 68 unsigned int cpu; 69 70 int last_residency; 71 int state_count; 72 struct cpuidle_state_usage states_usage[CPUIDLE_STATE_MAX]; 73 struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX]; 74 struct cpuidle_driver_kobj *kobj_driver; 75 struct cpuidle_device_kobj *kobj_dev; 76 struct list_head device_list; 77 78 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED 79 int safe_state_index; 80 cpumask_t coupled_cpus; 81 struct cpuidle_coupled *coupled; 82 #endif 83 }; 84 85 DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices); 86 DECLARE_PER_CPU(struct cpuidle_device, cpuidle_dev); 87 88 /** 89 * cpuidle_get_last_residency - retrieves the last state's residency time 90 * @dev: the target CPU 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 /* used by the cpuidle framework to setup the broadcast timer */ 108 unsigned int bctimer: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 /* the driver handles the cpus in cpumask */ 115 struct cpumask *cpumask; 116 }; 117 118 #ifdef CONFIG_CPU_IDLE 119 extern void disable_cpuidle(void); 120 121 extern int cpuidle_select(struct cpuidle_driver *drv, 122 struct cpuidle_device *dev); 123 extern int cpuidle_enter(struct cpuidle_driver *drv, 124 struct cpuidle_device *dev, int index); 125 extern void cpuidle_reflect(struct cpuidle_device *dev, int index); 126 127 extern int cpuidle_register_driver(struct cpuidle_driver *drv); 128 extern struct cpuidle_driver *cpuidle_get_driver(void); 129 extern struct cpuidle_driver *cpuidle_driver_ref(void); 130 extern void cpuidle_driver_unref(void); 131 extern void cpuidle_unregister_driver(struct cpuidle_driver *drv); 132 extern int cpuidle_register_device(struct cpuidle_device *dev); 133 extern void cpuidle_unregister_device(struct cpuidle_device *dev); 134 extern int cpuidle_register(struct cpuidle_driver *drv, 135 const struct cpumask *const coupled_cpus); 136 extern void cpuidle_unregister(struct cpuidle_driver *drv); 137 extern void cpuidle_pause_and_lock(void); 138 extern void cpuidle_resume_and_unlock(void); 139 extern void cpuidle_pause(void); 140 extern void cpuidle_resume(void); 141 extern int cpuidle_enable_device(struct cpuidle_device *dev); 142 extern void cpuidle_disable_device(struct cpuidle_device *dev); 143 extern int cpuidle_play_dead(void); 144 extern void cpuidle_use_deepest_state(bool enable); 145 146 extern struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev); 147 #else 148 static inline void disable_cpuidle(void) { } 149 static inline int cpuidle_select(struct cpuidle_driver *drv, 150 struct cpuidle_device *dev) 151 {return -ENODEV; } 152 static inline int cpuidle_enter(struct cpuidle_driver *drv, 153 struct cpuidle_device *dev, int index) 154 {return -ENODEV; } 155 static inline void cpuidle_reflect(struct cpuidle_device *dev, int index) { } 156 static inline int cpuidle_register_driver(struct cpuidle_driver *drv) 157 {return -ENODEV; } 158 static inline struct cpuidle_driver *cpuidle_get_driver(void) {return NULL; } 159 static inline struct cpuidle_driver *cpuidle_driver_ref(void) {return NULL; } 160 static inline void cpuidle_driver_unref(void) {} 161 static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { } 162 static inline int cpuidle_register_device(struct cpuidle_device *dev) 163 {return -ENODEV; } 164 static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { } 165 static inline int cpuidle_register(struct cpuidle_driver *drv, 166 const struct cpumask *const coupled_cpus) 167 {return -ENODEV; } 168 static inline void cpuidle_unregister(struct cpuidle_driver *drv) { } 169 static inline void cpuidle_pause_and_lock(void) { } 170 static inline void cpuidle_resume_and_unlock(void) { } 171 static inline void cpuidle_pause(void) { } 172 static inline void cpuidle_resume(void) { } 173 static inline int cpuidle_enable_device(struct cpuidle_device *dev) 174 {return -ENODEV; } 175 static inline void cpuidle_disable_device(struct cpuidle_device *dev) { } 176 static inline int cpuidle_play_dead(void) {return -ENODEV; } 177 static inline void cpuidle_use_deepest_state(bool enable) {} 178 static inline struct cpuidle_driver *cpuidle_get_cpu_driver( 179 struct cpuidle_device *dev) {return NULL; } 180 #endif 181 182 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED 183 void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a); 184 #else 185 static inline void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a) 186 { 187 } 188 #endif 189 190 /****************************** 191 * CPUIDLE GOVERNOR INTERFACE * 192 ******************************/ 193 194 struct cpuidle_governor { 195 char name[CPUIDLE_NAME_LEN]; 196 struct list_head governor_list; 197 unsigned int rating; 198 199 int (*enable) (struct cpuidle_driver *drv, 200 struct cpuidle_device *dev); 201 void (*disable) (struct cpuidle_driver *drv, 202 struct cpuidle_device *dev); 203 204 int (*select) (struct cpuidle_driver *drv, 205 struct cpuidle_device *dev); 206 void (*reflect) (struct cpuidle_device *dev, int index); 207 208 struct module *owner; 209 }; 210 211 #ifdef CONFIG_CPU_IDLE 212 extern int cpuidle_register_governor(struct cpuidle_governor *gov); 213 #else 214 static inline int cpuidle_register_governor(struct cpuidle_governor *gov) 215 {return 0;} 216 #endif 217 218 #ifdef CONFIG_ARCH_HAS_CPU_RELAX 219 #define CPUIDLE_DRIVER_STATE_START 1 220 #else 221 #define CPUIDLE_DRIVER_STATE_START 0 222 #endif 223 224 #endif /* _LINUX_CPUIDLE_H */ 225