/* * cpuidle.h - a generic framework for CPU idle power management * * (C) 2007 Venkatesh Pallipadi * Shaohua Li * Adam Belay * * This code is licenced under the GPL. */ #ifndef _LINUX_CPUIDLE_H #define _LINUX_CPUIDLE_H #include #include #include #define CPUIDLE_STATE_MAX 10 #define CPUIDLE_NAME_LEN 16 #define CPUIDLE_DESC_LEN 32 struct module; struct cpuidle_device; struct cpuidle_driver; /**************************** * CPUIDLE DEVICE INTERFACE * ****************************/ struct cpuidle_state_usage { unsigned long long disable; unsigned long long usage; unsigned long long time; /* in US */ }; struct cpuidle_state { char name[CPUIDLE_NAME_LEN]; char desc[CPUIDLE_DESC_LEN]; unsigned int flags; unsigned int exit_latency; /* in US */ int power_usage; /* in mW */ unsigned int target_residency; /* in US */ bool disabled; /* disabled on all CPUs */ int (*enter) (struct cpuidle_device *dev, struct cpuidle_driver *drv, int index); int (*enter_dead) (struct cpuidle_device *dev, int index); /* * CPUs execute ->enter_freeze with the local tick or entire timekeeping * suspended, so it must not re-enable interrupts at any point (even * temporarily) or attempt to change states of clock event devices. */ void (*enter_freeze) (struct cpuidle_device *dev, struct cpuidle_driver *drv, int index); }; /* Idle State Flags */ #define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */ #define CPUIDLE_FLAG_TIMER_STOP (0x04) /* timer is stopped on this state */ #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000) struct cpuidle_device_kobj; struct cpuidle_state_kobj; struct cpuidle_driver_kobj; struct cpuidle_device { unsigned int registered:1; unsigned int enabled:1; unsigned int cpu; int last_residency; struct cpuidle_state_usage states_usage[CPUIDLE_STATE_MAX]; struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX]; struct cpuidle_driver_kobj *kobj_driver; struct cpuidle_device_kobj *kobj_dev; struct list_head device_list; #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED int safe_state_index; cpumask_t coupled_cpus; struct cpuidle_coupled *coupled; #endif }; DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices); DECLARE_PER_CPU(struct cpuidle_device, cpuidle_dev); /** * cpuidle_get_last_residency - retrieves the last state's residency time * @dev: the target CPU */ static inline int cpuidle_get_last_residency(struct cpuidle_device *dev) { return dev->last_residency; } /**************************** * CPUIDLE DRIVER INTERFACE * ****************************/ struct cpuidle_driver { const char *name; struct module *owner; int refcnt; /* used by the cpuidle framework to setup the broadcast timer */ unsigned int bctimer:1; /* states array must be ordered in decreasing power consumption */ struct cpuidle_state states[CPUIDLE_STATE_MAX]; int state_count; int safe_state_index; /* the driver handles the cpus in cpumask */ struct cpumask *cpumask; }; #ifdef CONFIG_CPU_IDLE extern void disable_cpuidle(void); extern bool cpuidle_not_available(struct cpuidle_driver *drv, struct cpuidle_device *dev); extern int cpuidle_select(struct cpuidle_driver *drv, struct cpuidle_device *dev); extern int cpuidle_enter(struct cpuidle_driver *drv, struct cpuidle_device *dev, int index); extern void cpuidle_reflect(struct cpuidle_device *dev, int index); extern int cpuidle_register_driver(struct cpuidle_driver *drv); extern struct cpuidle_driver *cpuidle_get_driver(void); extern struct cpuidle_driver *cpuidle_driver_ref(void); extern void cpuidle_driver_unref(void); extern void cpuidle_unregister_driver(struct cpuidle_driver *drv); extern int cpuidle_register_device(struct cpuidle_device *dev); extern void cpuidle_unregister_device(struct cpuidle_device *dev); extern int cpuidle_register(struct cpuidle_driver *drv, const struct cpumask *const coupled_cpus); extern void cpuidle_unregister(struct cpuidle_driver *drv); extern void cpuidle_pause_and_lock(void); extern void cpuidle_resume_and_unlock(void); extern void cpuidle_pause(void); extern void cpuidle_resume(void); extern int cpuidle_enable_device(struct cpuidle_device *dev); extern void cpuidle_disable_device(struct cpuidle_device *dev); extern int cpuidle_play_dead(void); extern int cpuidle_find_deepest_state(struct cpuidle_driver *drv, struct cpuidle_device *dev); extern int cpuidle_enter_freeze(struct cpuidle_driver *drv, struct cpuidle_device *dev); extern struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev); #else static inline void disable_cpuidle(void) { } static inline bool cpuidle_not_available(struct cpuidle_driver *drv, struct cpuidle_device *dev) {return true; } static inline int cpuidle_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) {return -ENODEV; } static inline int cpuidle_enter(struct cpuidle_driver *drv, struct cpuidle_device *dev, int index) {return -ENODEV; } static inline void cpuidle_reflect(struct cpuidle_device *dev, int index) { } static inline int cpuidle_register_driver(struct cpuidle_driver *drv) {return -ENODEV; } static inline struct cpuidle_driver *cpuidle_get_driver(void) {return NULL; } static inline struct cpuidle_driver *cpuidle_driver_ref(void) {return NULL; } static inline void cpuidle_driver_unref(void) {} static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { } static inline int cpuidle_register_device(struct cpuidle_device *dev) {return -ENODEV; } static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { } static inline int cpuidle_register(struct cpuidle_driver *drv, const struct cpumask *const coupled_cpus) {return -ENODEV; } static inline void cpuidle_unregister(struct cpuidle_driver *drv) { } static inline void cpuidle_pause_and_lock(void) { } static inline void cpuidle_resume_and_unlock(void) { } static inline void cpuidle_pause(void) { } static inline void cpuidle_resume(void) { } static inline int cpuidle_enable_device(struct cpuidle_device *dev) {return -ENODEV; } static inline void cpuidle_disable_device(struct cpuidle_device *dev) { } static inline int cpuidle_play_dead(void) {return -ENODEV; } static inline int cpuidle_find_deepest_state(struct cpuidle_driver *drv, struct cpuidle_device *dev) {return -ENODEV; } static inline int cpuidle_enter_freeze(struct cpuidle_driver *drv, struct cpuidle_device *dev) {return -ENODEV; } static inline struct cpuidle_driver *cpuidle_get_cpu_driver( struct cpuidle_device *dev) {return NULL; } #endif /* kernel/sched/idle.c */ extern void sched_idle_set_state(struct cpuidle_state *idle_state); #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a); #else static inline void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a) { } #endif /****************************** * CPUIDLE GOVERNOR INTERFACE * ******************************/ struct cpuidle_governor { char name[CPUIDLE_NAME_LEN]; struct list_head governor_list; unsigned int rating; int (*enable) (struct cpuidle_driver *drv, struct cpuidle_device *dev); void (*disable) (struct cpuidle_driver *drv, struct cpuidle_device *dev); int (*select) (struct cpuidle_driver *drv, struct cpuidle_device *dev); void (*reflect) (struct cpuidle_device *dev, int index); struct module *owner; }; #ifdef CONFIG_CPU_IDLE extern int cpuidle_register_governor(struct cpuidle_governor *gov); #else static inline int cpuidle_register_governor(struct cpuidle_governor *gov) {return 0;} #endif #ifdef CONFIG_ARCH_HAS_CPU_RELAX #define CPUIDLE_DRIVER_STATE_START 1 #else #define CPUIDLE_DRIVER_STATE_START 0 #endif #endif /* _LINUX_CPUIDLE_H */