| 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_s2idle 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_s2idle) (struct cpuidle_device *dev, |
| 60 | struct cpuidle_driver *drv, |
| 61 | int index); |
| 62 | }; |
| 63 | |
| 64 | /* Idle State Flags */ |
| 65 | #define CPUIDLE_FLAG_NONE (0x00) |
| 66 | #define CPUIDLE_FLAG_POLLING (0x01) /* polling state */ |
| 67 | #define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */ |
| 68 | #define CPUIDLE_FLAG_TIMER_STOP (0x04) /* timer is stopped on this state */ |
| 69 | |
| 70 | #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000) |
| 71 | |
| 72 | struct cpuidle_device_kobj; |
| 73 | struct cpuidle_state_kobj; |
| 74 | struct cpuidle_driver_kobj; |
| 75 | |
| 76 | struct cpuidle_device { |
| 77 | unsigned int registered:1; |
| 78 | unsigned int enabled:1; |
| 79 | unsigned int use_deepest_state:1; |
| 80 | unsigned int cpu; |
| 81 | |
| 82 | int last_residency; |
| 83 | struct cpuidle_state_usage states_usage[CPUIDLE_STATE_MAX]; |
| 84 | struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX]; |
| 85 | struct cpuidle_driver_kobj *kobj_driver; |
| 86 | struct cpuidle_device_kobj *kobj_dev; |
| 87 | struct list_head device_list; |
| 88 | |
| 89 | #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED |
| 90 | cpumask_t coupled_cpus; |
| 91 | struct cpuidle_coupled *coupled; |
| 92 | #endif |
| 93 | }; |
| 94 | |
| 95 | DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices); |
| 96 | DECLARE_PER_CPU(struct cpuidle_device, cpuidle_dev); |
| 97 | |
| 98 | /** |
| 99 | * cpuidle_get_last_residency - retrieves the last state's residency time |
| 100 | * @dev: the target CPU |
| 101 | */ |
| 102 | static inline int cpuidle_get_last_residency(struct cpuidle_device *dev) |
| 103 | { |
| 104 | return dev->last_residency; |
| 105 | } |
| 106 | |
| 107 | |
| 108 | /**************************** |
| 109 | * CPUIDLE DRIVER INTERFACE * |
| 110 | ****************************/ |
| 111 | |
| 112 | struct cpuidle_driver { |
| 113 | const char *name; |
| 114 | struct module *owner; |
| 115 | int refcnt; |
| 116 | |
| 117 | /* used by the cpuidle framework to setup the broadcast timer */ |
| 118 | unsigned int bctimer:1; |
| 119 | /* states array must be ordered in decreasing power consumption */ |
| 120 | struct cpuidle_state states[CPUIDLE_STATE_MAX]; |
| 121 | int state_count; |
| 122 | int safe_state_index; |
| 123 | |
| 124 | /* the driver handles the cpus in cpumask */ |
| 125 | struct cpumask *cpumask; |
| 126 | }; |
| 127 | |
| 128 | #ifdef CONFIG_CPU_IDLE |
| 129 | extern void disable_cpuidle(void); |
| 130 | extern bool cpuidle_not_available(struct cpuidle_driver *drv, |
| 131 | struct cpuidle_device *dev); |
| 132 | |
| 133 | extern int cpuidle_select(struct cpuidle_driver *drv, |
| 134 | struct cpuidle_device *dev, |
| 135 | bool *stop_tick); |
| 136 | extern int cpuidle_enter(struct cpuidle_driver *drv, |
| 137 | struct cpuidle_device *dev, int index); |
| 138 | extern void cpuidle_reflect(struct cpuidle_device *dev, int index); |
| 139 | |
| 140 | extern int cpuidle_register_driver(struct cpuidle_driver *drv); |
| 141 | extern struct cpuidle_driver *cpuidle_get_driver(void); |
| 142 | extern struct cpuidle_driver *cpuidle_driver_ref(void); |
| 143 | extern void cpuidle_driver_unref(void); |
| 144 | extern void cpuidle_unregister_driver(struct cpuidle_driver *drv); |
| 145 | extern int cpuidle_register_device(struct cpuidle_device *dev); |
| 146 | extern void cpuidle_unregister_device(struct cpuidle_device *dev); |
| 147 | extern int cpuidle_register(struct cpuidle_driver *drv, |
| 148 | const struct cpumask *const coupled_cpus); |
| 149 | extern void cpuidle_unregister(struct cpuidle_driver *drv); |
| 150 | extern void cpuidle_pause_and_lock(void); |
| 151 | extern void cpuidle_resume_and_unlock(void); |
| 152 | extern void cpuidle_pause(void); |
| 153 | extern void cpuidle_resume(void); |
| 154 | extern int cpuidle_enable_device(struct cpuidle_device *dev); |
| 155 | extern void cpuidle_disable_device(struct cpuidle_device *dev); |
| 156 | extern int cpuidle_play_dead(void); |
| 157 | |
| 158 | extern struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev); |
| 159 | static inline struct cpuidle_device *cpuidle_get_device(void) |
| 160 | {return __this_cpu_read(cpuidle_devices); } |
| 161 | extern unsigned int cpuidle_get_target_residency(int cpu, int state); |
| 162 | #else |
| 163 | static inline void disable_cpuidle(void) { } |
| 164 | static inline bool cpuidle_not_available(struct cpuidle_driver *drv, |
| 165 | struct cpuidle_device *dev) |
| 166 | {return true; } |
| 167 | static inline int cpuidle_select(struct cpuidle_driver *drv, |
| 168 | struct cpuidle_device *dev, bool *stop_tick) |
| 169 | {return -ENODEV; } |
| 170 | static inline int cpuidle_enter(struct cpuidle_driver *drv, |
| 171 | struct cpuidle_device *dev, int index) |
| 172 | {return -ENODEV; } |
| 173 | static inline void cpuidle_reflect(struct cpuidle_device *dev, int index) { } |
| 174 | static inline int cpuidle_register_driver(struct cpuidle_driver *drv) |
| 175 | {return -ENODEV; } |
| 176 | static inline struct cpuidle_driver *cpuidle_get_driver(void) {return NULL; } |
| 177 | static inline struct cpuidle_driver *cpuidle_driver_ref(void) {return NULL; } |
| 178 | static inline void cpuidle_driver_unref(void) {} |
| 179 | static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { } |
| 180 | static inline int cpuidle_register_device(struct cpuidle_device *dev) |
| 181 | {return -ENODEV; } |
| 182 | static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { } |
| 183 | static inline int cpuidle_register(struct cpuidle_driver *drv, |
| 184 | const struct cpumask *const coupled_cpus) |
| 185 | {return -ENODEV; } |
| 186 | static inline void cpuidle_unregister(struct cpuidle_driver *drv) { } |
| 187 | static inline void cpuidle_pause_and_lock(void) { } |
| 188 | static inline void cpuidle_resume_and_unlock(void) { } |
| 189 | static inline void cpuidle_pause(void) { } |
| 190 | static inline void cpuidle_resume(void) { } |
| 191 | static inline int cpuidle_enable_device(struct cpuidle_device *dev) |
| 192 | {return -ENODEV; } |
| 193 | static inline void cpuidle_disable_device(struct cpuidle_device *dev) { } |
| 194 | static inline int cpuidle_play_dead(void) {return -ENODEV; } |
| 195 | static inline struct cpuidle_driver *cpuidle_get_cpu_driver( |
| 196 | struct cpuidle_device *dev) {return NULL; } |
| 197 | static inline struct cpuidle_device *cpuidle_get_device(void) {return NULL; } |
| 198 | static inline unsigned int cpuidle_get_target_residency(int cpu, int state) {return UINT_MAX;} |
| 199 | #endif |
| 200 | |
| 201 | #ifdef CONFIG_CPU_IDLE |
| 202 | extern int cpuidle_find_deepest_state(struct cpuidle_driver *drv, |
| 203 | struct cpuidle_device *dev); |
| 204 | extern int cpuidle_enter_s2idle(struct cpuidle_driver *drv, |
| 205 | struct cpuidle_device *dev); |
| 206 | extern void cpuidle_use_deepest_state(bool enable); |
| 207 | #else |
| 208 | static inline int cpuidle_find_deepest_state(struct cpuidle_driver *drv, |
| 209 | struct cpuidle_device *dev) |
| 210 | {return -ENODEV; } |
| 211 | static inline int cpuidle_enter_s2idle(struct cpuidle_driver *drv, |
| 212 | struct cpuidle_device *dev) |
| 213 | {return -ENODEV; } |
| 214 | static inline void cpuidle_use_deepest_state(bool enable) |
| 215 | { |
| 216 | } |
| 217 | #endif |
| 218 | |
| 219 | /* kernel/sched/idle.c */ |
| 220 | extern void sched_idle_set_state(struct cpuidle_state *idle_state, int index); |
| 221 | extern void default_idle_call(void); |
| 222 | |
| 223 | #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED |
| 224 | void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a); |
| 225 | #else |
| 226 | static inline void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a) |
| 227 | { |
| 228 | } |
| 229 | #endif |
| 230 | |
| 231 | #if defined(CONFIG_CPU_IDLE) && defined(CONFIG_ARCH_HAS_CPU_RELAX) |
| 232 | void cpuidle_poll_state_init(struct cpuidle_driver *drv); |
| 233 | #else |
| 234 | static inline void cpuidle_poll_state_init(struct cpuidle_driver *drv) {} |
| 235 | #endif |
| 236 | |
| 237 | /****************************** |
| 238 | * CPUIDLE GOVERNOR INTERFACE * |
| 239 | ******************************/ |
| 240 | |
| 241 | struct cpuidle_governor { |
| 242 | char name[CPUIDLE_NAME_LEN]; |
| 243 | struct list_head governor_list; |
| 244 | unsigned int rating; |
| 245 | |
| 246 | int (*enable) (struct cpuidle_driver *drv, |
| 247 | struct cpuidle_device *dev); |
| 248 | void (*disable) (struct cpuidle_driver *drv, |
| 249 | struct cpuidle_device *dev); |
| 250 | |
| 251 | int (*select) (struct cpuidle_driver *drv, |
| 252 | struct cpuidle_device *dev, |
| 253 | bool *stop_tick); |
| 254 | void (*reflect) (struct cpuidle_device *dev, int index); |
| 255 | }; |
| 256 | |
| 257 | #ifdef CONFIG_CPU_IDLE |
| 258 | extern int cpuidle_register_governor(struct cpuidle_governor *gov); |
| 259 | #else |
| 260 | static inline int cpuidle_register_governor(struct cpuidle_governor *gov) |
| 261 | {return 0;} |
| 262 | #endif |
| 263 | |
| 264 | #define CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx) \ |
| 265 | ({ \ |
| 266 | int __ret; \ |
| 267 | \ |
| 268 | if (!idx) { \ |
| 269 | cpu_do_idle(); \ |
| 270 | return idx; \ |
| 271 | } \ |
| 272 | \ |
| 273 | __ret = cpu_pm_enter(); \ |
| 274 | if (!__ret) { \ |
| 275 | __ret = low_level_idle_enter(idx); \ |
| 276 | cpu_pm_exit(); \ |
| 277 | } \ |
| 278 | \ |
| 279 | __ret ? -1 : idx; \ |
| 280 | }) |
| 281 | |
| 282 | #endif /* _LINUX_CPUIDLE_H */ |