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/*
* 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 */
#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];
u64 exit_latency_ns;
u64 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.
*/
void (*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 */
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[
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