/* * 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/module.h> #include <linux/kobject.h> #include <linux/completion.h> #define CPUIDLE_STATE_MAX 8 #define CPUIDLE_NAME_LEN 16 struct cpuidle_device; /**************************** * CPUIDLE DEVICE INTERFACE * ****************************/ struct cpuidle_state { char name[CPUIDLE_NAME_LEN]; void *driver_data; unsigned int flags; unsigned int exit_latency; /* in US */ unsigned int power_usage; /* in mW */ unsigned int target_residency; /* in US */ unsigned int usage; unsigned int time; /* in US */ int (*enter) (struct cpuidle_device *dev, struct cpuidle_state *state); }; /* Idle State Flags */ #define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */ #define CPUIDLE_FLAG_CHECK_BM (0x02) /* BM activity will exit state */ #define CPUIDLE_FLAG_SHALLOW (0x10) /* low latency, minimal savings */ #define CPUIDLE_FLAG_BALANCED (0x20) /* medium latency, moderate savings */ #define CPUIDLE_FLAG_DEEP (0x40) /* high latency, large savings */ #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000) /** * cpuidle_get_statedata - retrieves private driver state data * @state: the state */ static inline void * cpuidle_get_statedata(struct cpuidle_state *state) { return state->driver_data; } /** * cpuidle_set_statedata - stores private driver state data * @state: the state * @data: the private data */ static inline void cpuidle_set_statedata(struct cpuidle_state *state, void *data) { state->driver_data = data; } struct cpuidle_state_kobj { struct cpuidle_state *state; struct completion kobj_unregister; struct kobject kobj; }; struct cpuidle_device { int enabled:1; unsigned int cpu; int last_residency; int state_count; struct cpuidle_state states[CPUIDLE_STATE_MAX]; struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX]; struct cpuidle_state *last_state; struct list_head device_list; struct kobject kobj; struct completion kobj_unregister; void *governor_data; struct cpuidle_state *safe_state; }; DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices); /** * cpuidle_get_last_residency - retrieves the last state's residency time * @dev: the target CPU * * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_VALID isn't set */ static inline int cpuidle_get_last_residency(struct cpuidle_device *dev) { return dev->last_residency; } /**************************** * CPUIDLE DRIVER INTERFACE * ****************************/ struct cpuidle_driver { char name[CPUIDLE_NAME_LEN]; struct module *owner; }; #ifdef CONFIG_CPU_IDLE extern int cpuidle_register_driver(struct cpuidle_driver *drv); 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 void cpuidle_pause_and_lock(void); extern void cpuidle_resume_and_unlock(void); extern int cpuidle_enable_device(struct cpuidle_device *dev); extern void cpuidle_disable_device(struct cpuidle_device *dev); #else static inline int cpuidle_register_driver(struct cpuidle_driver *drv) {return 0;} static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { } static inline int cpuidle_register_device(struct cpuidle_device *dev) {return 0;} static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { } static inline void cpuidle_pause_and_lock(void) { } static inline void cpuidle_resume_and_unlock(void) { } static inline int cpuidle_enable_device(struct cpuidle_device *dev) {return 0;} static inline void cpuidle_disable_device(struct cpuidle_device *dev) { } #endif /****************************** * CPUIDLE GOVERNOR INTERFACE * ******************************/ struct cpuidle_governor { char name[CPUIDLE_NAME_LEN]; struct list_head governor_list; unsigned int rating; int (*enable) (struct cpuidle_device *dev); void (*disable) (struct cpuidle_device *dev); int (*select) (struct cpuidle_device *dev); void (*reflect) (struct cpuidle_device *dev); struct module *owner; }; #ifdef CONFIG_CPU_IDLE extern int cpuidle_register_governor(struct cpuidle_governor *gov); extern void cpuidle_unregister_governor(struct cpuidle_governor *gov); #else static inline int cpuidle_register_governor(struct cpuidle_governor *gov) {return 0;} static inline void cpuidle_unregister_governor(struct cpuidle_governor *gov) { } #endif #endif /* _LINUX_CPUIDLE_H */