linux/include/linux/cpuidle.h

/*
 * cpuidle.h - a generic framework for CPU idle power management
 *
 * (C) 2007 Venkatesh Pallipadi <[email protected]>
 *          Shaohua Li <[email protected]>
 *          Adam Belay <[email protected]>
 *
 * 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>
#include <linux/context_tracking.h>

#define CPUIDLE_STATE_MAX …
#define CPUIDLE_NAME_LEN …
#define CPUIDLE_DESC_LEN …

struct module;

struct cpuidle_device;
struct cpuidle_driver;


/****************************
 * CPUIDLE DEVICE INTERFACE *
 ****************************/

#define CPUIDLE_STATE_DISABLED_BY_USER …
#define CPUIDLE_STATE_DISABLED_BY_DRIVER …

struct cpuidle_state_usage { … };

struct cpuidle_state { … };

/* Idle State Flags */
#define CPUIDLE_FLAG_NONE …
#define CPUIDLE_FLAG_POLLING …
#define CPUIDLE_FLAG_COUPLED …
#define CPUIDLE_FLAG_TIMER_STOP …
#define CPUIDLE_FLAG_UNUSABLE …
#define CPUIDLE_FLAG_OFF …
#define CPUIDLE_FLAG_TLB_FLUSHED …
#define CPUIDLE_FLAG_RCU_IDLE …

struct cpuidle_device_kobj;
struct cpuidle_state_kobj;
struct cpuidle_driver_kobj;

struct cpuidle_device { … };

DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices);
DECLARE_PER_CPU(struct cpuidle_device, cpuidle_dev);

static __always_inline void ct_cpuidle_enter(void)
{ … }

static __always_inline void ct_cpuidle_exit(void)
{ … }

/****************************
 * CPUIDLE DRIVER INTERFACE *
 ****************************/

struct cpuidle_driver { … };

#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)
{ … }
#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 { … };

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, is_rcu) …

#define CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx) …

#define CPU_PM_CPU_IDLE_ENTER_RETENTION(low_level_idle_enter, idx) …

#define CPU_PM_CPU_IDLE_ENTER_PARAM(low_level_idle_enter, idx, state) …

#define CPU_PM_CPU_IDLE_ENTER_PARAM_RCU(low_level_idle_enter, idx, state) …

#define CPU_PM_CPU_IDLE_ENTER_RETENTION_PARAM(low_level_idle_enter, idx, state) …

#define CPU_PM_CPU_IDLE_ENTER_RETENTION_PARAM_RCU(low_level_idle_enter, idx, state) …

#endif /* _LINUX_CPUIDLE_H */