| 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/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 | * CPUs execute ->enter_freeze with the local tick or entire timekeeping |
| 56 | * suspended, so it must not re-enable interrupts at any point (even |
| 57 | * temporarily) or attempt to change states of clock event devices. |
| 58 | */ |
| 59 | void (*enter_freeze) (struct cpuidle_device *dev, |
| 60 | struct cpuidle_driver *drv, |
| 61 | int index); |
| 62 | }; |
| 63 | |
| 64 | /* Idle State Flags */ |
| 65 | #define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */ |
| 66 | #define CPUIDLE_FLAG_TIMER_STOP (0x04) /* timer is stopped on this state */ |
| 67 | |
| 68 | #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000) |
| 69 | |
| 70 | struct cpuidle_device_kobj; |
| 71 | struct cpuidle_state_kobj; |
| 72 | struct cpuidle_driver_kobj; |
| 73 | |
| 74 | struct cpuidle_device { |
| 75 | unsigned int registered:1; |
| 76 | unsigned int enabled:1; |
| 77 | unsigned int cpu; |
| 78 | |
| 79 | int last_residency; |
| 80 | struct cpuidle_state_usage states_usage[CPUIDLE_STATE_MAX]; |
| 81 | struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX]; |
| 82 | struct cpuidle_driver_kobj *kobj_driver; |
| 83 | struct cpuidle_device_kobj *kobj_dev; |
| 84 | struct list_head device_list; |
| 85 | |
| 86 | #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED |
| 87 | cpumask_t coupled_cpus; |
| 88 | struct cpuidle_coupled *coupled; |
| 89 | #endif |
| 90 | }; |
| 91 | |
| 92 | DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices); |
| 93 | DECLARE_PER_CPU(struct cpuidle_device, cpuidle_dev); |
| 94 | |
| 95 | /** |
| 96 | * cpuidle_get_last_residency - retrieves the last state's residency time |
| 97 | * @dev: the target CPU |
| 98 | */ |
| 99 | static inline int cpuidle_get_last_residency(struct cpuidle_device *dev) |
| 100 | { |
| 101 | return dev->last_residency; |
| 102 | } |
| 103 | |
| 104 | |
| 105 | /**************************** |
| 106 | * CPUIDLE DRIVER INTERFACE * |
| 107 | ****************************/ |
| 108 | |
| 109 | struct cpuidle_driver { |
| 110 | const char *name; |
| 111 | struct module *owner; |
| 112 | int refcnt; |
| 113 | |
| 114 | /* used by the cpuidle framework to setup the broadcast timer */ |
| 115 | unsigned int bctimer:1; |
| 116 | /* states array must be ordered in decreasing power consumption */ |
| 117 | struct cpuidle_state states[CPUIDLE_STATE_MAX]; |
| 118 | int state_count; |
| 119 | int safe_state_index; |
| 120 | |
| 121 | /* the driver handles the cpus in cpumask */ |
| 122 | struct cpumask *cpumask; |
| 123 | }; |
| 124 | |
| 125 | #ifdef CONFIG_CPU_IDLE |
| 126 | extern void disable_cpuidle(void); |
| 127 | extern bool cpuidle_not_available(struct cpuidle_driver *drv, |
| 128 | struct cpuidle_device *dev); |
| 129 | |
| 130 | extern int cpuidle_select(struct cpuidle_driver *drv, |
| 131 | struct cpuidle_device *dev); |
| 132 | extern int cpuidle_enter(struct cpuidle_driver *drv, |
| 133 | struct cpuidle_device *dev, int index); |
| 134 | extern void cpuidle_reflect(struct cpuidle_device *dev, int index); |
| 135 | |
| 136 | extern int cpuidle_register_driver(struct cpuidle_driver *drv); |
| 137 | extern struct cpuidle_driver *cpuidle_get_driver(void); |
| 138 | extern struct cpuidle_driver *cpuidle_driver_ref(void); |
| 139 | extern void cpuidle_driver_unref(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 | extern int cpuidle_register(struct cpuidle_driver *drv, |
| 144 | const struct cpumask *const coupled_cpus); |
| 145 | extern void cpuidle_unregister(struct cpuidle_driver *drv); |
| 146 | extern void cpuidle_pause_and_lock(void); |
| 147 | extern void cpuidle_resume_and_unlock(void); |
| 148 | extern void cpuidle_pause(void); |
| 149 | extern void cpuidle_resume(void); |
| 150 | extern int cpuidle_enable_device(struct cpuidle_device *dev); |
| 151 | extern void cpuidle_disable_device(struct cpuidle_device *dev); |
| 152 | extern int cpuidle_play_dead(void); |
| 153 | |
| 154 | extern struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev); |
| 155 | #else |
| 156 | static inline void disable_cpuidle(void) { } |
| 157 | static inline bool cpuidle_not_available(struct cpuidle_driver *drv, |
| 158 | struct cpuidle_device *dev) |
| 159 | {return true; } |
| 160 | static inline int cpuidle_select(struct cpuidle_driver *drv, |
| 161 | struct cpuidle_device *dev) |
| 162 | {return -ENODEV; } |
| 163 | static inline int cpuidle_enter(struct cpuidle_driver *drv, |
| 164 | struct cpuidle_device *dev, int index) |
| 165 | {return -ENODEV; } |
| 166 | static inline void cpuidle_reflect(struct cpuidle_device *dev, int index) { } |
| 167 | static inline int cpuidle_register_driver(struct cpuidle_driver *drv) |
| 168 | {return -ENODEV; } |
| 169 | static inline struct cpuidle_driver *cpuidle_get_driver(void) {return NULL; } |
| 170 | static inline struct cpuidle_driver *cpuidle_driver_ref(void) {return NULL; } |
| 171 | static inline void cpuidle_driver_unref(void) {} |
| 172 | static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { } |
| 173 | static inline int cpuidle_register_device(struct cpuidle_device *dev) |
| 174 | {return -ENODEV; } |
| 175 | static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { } |
| 176 | static inline int cpuidle_register(struct cpuidle_driver *drv, |
| 177 | const struct cpumask *const coupled_cpus) |
| 178 | {return -ENODEV; } |
| 179 | static inline void cpuidle_unregister(struct cpuidle_driver *drv) { } |
| 180 | static inline void cpuidle_pause_and_lock(void) { } |
| 181 | static inline void cpuidle_resume_and_unlock(void) { } |
| 182 | static inline void cpuidle_pause(void) { } |
| 183 | static inline void cpuidle_resume(void) { } |
| 184 | static inline int cpuidle_enable_device(struct cpuidle_device *dev) |
| 185 | {return -ENODEV; } |
| 186 | static inline void cpuidle_disable_device(struct cpuidle_device *dev) { } |
| 187 | static inline int cpuidle_play_dead(void) {return -ENODEV; } |
| 188 | static inline struct cpuidle_driver *cpuidle_get_cpu_driver( |
| 189 | struct cpuidle_device *dev) {return NULL; } |
| 190 | #endif |
| 191 | |
| 192 | #if defined(CONFIG_CPU_IDLE) && defined(CONFIG_SUSPEND) |
| 193 | extern int cpuidle_find_deepest_state(struct cpuidle_driver *drv, |
| 194 | struct cpuidle_device *dev); |
| 195 | extern int cpuidle_enter_freeze(struct cpuidle_driver *drv, |
| 196 | struct cpuidle_device *dev); |
| 197 | #else |
| 198 | static inline int cpuidle_find_deepest_state(struct cpuidle_driver *drv, |
| 199 | struct cpuidle_device *dev) |
| 200 | {return -ENODEV; } |
| 201 | static inline int cpuidle_enter_freeze(struct cpuidle_driver *drv, |
| 202 | struct cpuidle_device *dev) |
| 203 | {return -ENODEV; } |
| 204 | #endif |
| 205 | |
| 206 | /* kernel/sched/idle.c */ |
| 207 | extern void sched_idle_set_state(struct cpuidle_state *idle_state); |
| 208 | extern void default_idle_call(void); |
| 209 | |
| 210 | #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED |
| 211 | void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a); |
| 212 | #else |
| 213 | static inline void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a) |
| 214 | { |
| 215 | } |
| 216 | #endif |
| 217 | |
| 218 | /****************************** |
| 219 | * CPUIDLE GOVERNOR INTERFACE * |
| 220 | ******************************/ |
| 221 | |
| 222 | struct cpuidle_governor { |
| 223 | char name[CPUIDLE_NAME_LEN]; |
| 224 | struct list_head governor_list; |
| 225 | unsigned int rating; |
| 226 | |
| 227 | int (*enable) (struct cpuidle_driver *drv, |
| 228 | struct cpuidle_device *dev); |
| 229 | void (*disable) (struct cpuidle_driver *drv, |
| 230 | struct cpuidle_device *dev); |
| 231 | |
| 232 | int (*select) (struct cpuidle_driver *drv, |
| 233 | struct cpuidle_device *dev); |
| 234 | void (*reflect) (struct cpuidle_device *dev, int index); |
| 235 | |
| 236 | struct module *owner; |
| 237 | }; |
| 238 | |
| 239 | #ifdef CONFIG_CPU_IDLE |
| 240 | extern int cpuidle_register_governor(struct cpuidle_governor *gov); |
| 241 | #else |
| 242 | static inline int cpuidle_register_governor(struct cpuidle_governor *gov) |
| 243 | {return 0;} |
| 244 | #endif |
| 245 | |
| 246 | #ifdef CONFIG_ARCH_HAS_CPU_RELAX |
| 247 | #define CPUIDLE_DRIVER_STATE_START 1 |
| 248 | #else |
| 249 | #define CPUIDLE_DRIVER_STATE_START 0 |
| 250 | #endif |
| 251 | |
| 252 | #endif /* _LINUX_CPUIDLE_H */ |