/* * cpuidle.h - a generic framework for CPU idle power management * * (C) 2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> * Shaohua Li <shaohua.li@intel.com> * Adam Belay <abelay@novell.com> * * This code is licenced under the GPL. */ #ifndef _LINUX_CPUIDLE_H #define _LINUX_CPUIDLE_H #include <linux/percpu.h> #include <linux/list.h> #include <linux/hrtimer.h> #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 * ****************************/ #define CPUIDLE_STATE_DISABLED_BY_USER BIT(0) #define CPUIDLE_STATE_DISABLED_BY_DRIVER BIT(1) struct cpuidle_state_usage { unsigned long long disable; unsigned long long usage; u64 time_ns; unsigned long long above; /* Number of times it's been too deep */ unsigned long long below; /* Number of times it's been too shallow */ unsigned long long rejected; /* Number of times idle entry was rejected */ #ifdef CONFIG_SUSPEND unsigned long long s2idle_usage; unsigned long long s2idle_time; /* in US */ #endif }; struct cpuidle_state { char name[CPUIDLE_NAME_LEN]; char desc[CPUIDLE_DESC_LEN]; s64 exit_latency_ns; s64 target_residency_ns; unsigned int flags; unsigned int exit_latency; /* in US */ int power_usage; /* in mW */ unsigned int target_residency; /* in US */ int (*enter) (struct cpuidle_device *dev, struct cpuidle_driver *drv, int index); int (*enter_dead) (struct cpuidle_device *dev, int index); /* * CPUs execute ->enter_s2idle 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. * * This callback may point to the same function as ->enter if all of * the above requirements are met by it. */ int (*enter_s2idle)(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index); }; /* Idle State Flags */ #define CPUIDLE_FLAG_NONE (0x00) #define CPUIDLE_FLAG_POLLING BIT(0) /* polling state */ #define CPUIDLE_FLAG_COUPLED BIT(1) /* state applies to multiple cpus */ #define CPUIDLE_FLAG_TIMER_STOP BIT(2) /* timer is stopped on this state */ #define CPUIDLE_FLAG_UNUSABLE BIT(3) /* avoid using this state */ #define CPUIDLE_FLAG_OFF BIT(4) /* disable this state by default */ #define CPUIDLE_FLAG_TLB_FLUSHED BIT(5) /* idle-state flushes TLBs */ #define CPUIDLE_FLAG_RCU_IDLE BIT(6) /* idle-state takes care of RCU */ 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 poll_time_limit:1; unsigned int cpu; ktime_t next_hrtimer; int last_state_idx; u64 last_residency_ns; u64 poll_limit_ns; u64 forced_idle_latency_limit_ns; 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 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 DRIVER INTERFACE * ****************************/ struct cpuidle_driver { const char *name; struct module *owner; /* 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; /* preferred governor to switch at register time */ const char *governor; }; #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, bool *stop_tick); 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 u64 cpuidle_poll_time(struct cpuidle_driver *drv, struct cpuidle_device *dev); extern int cpuidle_register_driver(struct cpuidle_driver *drv); extern struct cpuidle_driver *cpuidle_get_driver(void); extern void cpuidle_driver_state_disabled(struct cpuidle_driver *drv, int idx, bool disable); 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 struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev); static inline struct cpuidle_device *cpuidle_get_device(void) {return __this_cpu_read(cpuidle_devices); } #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, bool *stop_tick) {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 u64 cpuidle_poll_time(struct cpuidle_driver *drv, struct cpuidle_device *dev) {return 0; } 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 void cpuidle_driver_state_disabled(struct cpuidle_driver *drv, int idx, bool disable) { } 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 struct cpuidle_driver *cpuidle_get_cpu_driver( struct cpuidle_device *dev) {return NULL; } static inline struct cpuidle_device *cpuidle_get_device(void) {return NULL; } #endif #ifdef CONFIG_CPU_IDLE extern int cpuidle_find_deepest_state(struct cpuidle_driver *drv, struct cpuidle_device *dev, u64 latency_limit_ns); extern int cpuidle_enter_s2idle(struct cpuidle_driver *drv, struct cpuidle_device *dev); extern void cpuidle_use_deepest_state(u64 latency_limit_ns); #else static inline int cpuidle_find_deepest_state(struct cpuidle_driver *drv, struct cpuidle_device *dev, u64 latency_limit_ns) {return -ENODEV; } static inline int cpuidle_enter_s2idle(struct cpuidle_driver *drv, struct cpuidle_device *dev) {return -ENODEV; } static inline void cpuidle_use_deepest_state(u64 latency_limit_ns) { } #endif /* kernel/sched/idle.c */ extern void sched_idle_set_state(struct cpuidle_state *idle_state); extern void default_idle_call(void); #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 #if defined(CONFIG_CPU_IDLE) && defined(CONFIG_ARCH_HAS_CPU_RELAX) void cpuidle_poll_state_init(struct cpuidle_driver *drv); #else static inline void cpuidle_poll_state_init(struct cpuidle_driver *drv) {} #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, bool *stop_tick); void (*reflect) (struct cpuidle_device *dev, int index); }; extern int cpuidle_register_governor(struct cpuidle_governor *gov); extern s64 cpuidle_governor_latency_req(unsigned int cpu); #define __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, \ idx, \ state, \ is_retention) \ ({ \ int __ret = 0; \ \ if (!idx) { \ cpu_do_idle(); \ return idx; \ } \ \ if (!is_retention) \ __ret = cpu_pm_enter(); \ if (!__ret) { \ __ret = low_level_idle_enter(state); \ if (!is_retention) \ cpu_pm_exit(); \ } \ \ __ret ? -1 : idx; \ }) #define CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx) \ __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx, idx, 0) #define CPU_PM_CPU_IDLE_ENTER_RETENTION(low_level_idle_enter, idx) \ __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx, idx, 1) #define CPU_PM_CPU_IDLE_ENTER_PARAM(low_level_idle_enter, idx, state) \ __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx, state, 0) #define CPU_PM_CPU_IDLE_ENTER_RETENTION_PARAM(low_level_idle_enter, idx, state) \ __CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx, state, 1) #endif /* _LINUX_CPUIDLE_H */