[deliverable/linux.git] / include / linux / cpuidle.h

/*
 * 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/kobject.h>
#include <linux/completion.h>
#include <linux/hrtimer.h>

#define CPUIDLE_STATE_MAX	8
#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);
};

/* Idle State Flags */
#define CPUIDLE_FLAG_TIME_VALID	(0x01) /* is residency time measurable? */
#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 {
	unsigned int		registered:1;
	unsigned int		enabled:1;
	unsigned int		cpu;

	int			last_residency;
	int			state_count;
	struct cpuidle_state_usage	states_usage[CPUIDLE_STATE_MAX];
	struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX];
	struct cpuidle_driver_kobj *kobj_driver;
	struct list_head 	device_list;
	struct kobject		kobj;
	struct completion	kobj_unregister;

#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);

/**
 * 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 {
	const char		*name;
	struct module 		*owner;
	int                     refcnt;

	/* set to 1 to use the core cpuidle time keeping (for all states). */
	unsigned int		en_core_tk_irqen:1;
	/* states array must be ordered in decreasing power consumption */
	struct cpuidle_state	states[CPUIDLE_STATE_MAX];
	int			state_count;
	int			safe_state_index;
};

#ifdef CONFIG_CPU_IDLE
extern void disable_cpuidle(void);
extern int cpuidle_idle_call(void);
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 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_wrap_enter(struct cpuidle_device *dev,
				struct cpuidle_driver *drv, int index,
				int (*enter)(struct cpuidle_device *dev,
					struct cpuidle_driver *drv, int index));
extern int cpuidle_play_dead(void);

extern struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev);
extern int cpuidle_register_cpu_driver(struct cpuidle_driver *drv, int cpu);
extern void cpuidle_unregister_cpu_driver(struct cpuidle_driver *drv, int cpu);

#else
static inline void disable_cpuidle(void) { }
static inline int cpuidle_idle_call(void) { return -ENODEV; }
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 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_wrap_enter(struct cpuidle_device *dev,
				struct cpuidle_driver *drv, int index,
				int (*enter)(struct cpuidle_device *dev,
					struct cpuidle_driver *drv, int index))
{ return -ENODEV; }
static inline int cpuidle_play_dead(void) {return -ENODEV; }
#endif

#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);
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

#ifdef CONFIG_ARCH_HAS_CPU_RELAX
#define CPUIDLE_DRIVER_STATE_START	1
#else
#define CPUIDLE_DRIVER_STATE_START	0
#endif

#endif /* _LINUX_CPUIDLE_H */
Commit	Line	Data
4f86d3a8 LB	1	/*
	2	* cpuidle.h - a generic framework for CPU idle power management
	3	*
	4	* (C) 2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
	5	* Shaohua Li <shaohua.li@intel.com>
	6	* Adam Belay <abelay@novell.com>
	7	*
	8	* This code is licenced under the GPL.
	9	*/
	10
	11	#ifndef _LINUX_CPUIDLE_H
	12	#define _LINUX_CPUIDLE_H
	13
	14	#include <linux/percpu.h>
	15	#include <linux/list.h>
4f86d3a8 LB	16	#include <linux/kobject.h>
4f86d3a8 LB	17	#include <linux/completion.h>
e1689795	18	#include <linux/hrtimer.h>
4f86d3a8 LB	19
	20	#define CPUIDLE_STATE_MAX 8
	21	#define CPUIDLE_NAME_LEN 16
4fcb2fcd	22	#define CPUIDLE_DESC_LEN 32
4f86d3a8	23
de477254 PG	24	struct module;
de477254 PG	25
4f86d3a8	26	struct cpuidle_device;
46bcfad7	27	struct cpuidle_driver;
4f86d3a8 LB	28
	29
	30	/****************************
	31	* CPUIDLE DEVICE INTERFACE *
	32	****************************/
	33
4202735e	34	struct cpuidle_state_usage {
dc7fd275	35	unsigned long long disable;
4202735e DD	36	unsigned long long usage;
	37	unsigned long long time; /* in US */
	38	};
	39
4f86d3a8 LB	40	struct cpuidle_state {
4f86d3a8 LB	41	char name[CPUIDLE_NAME_LEN];
4fcb2fcd	42	char desc[CPUIDLE_DESC_LEN];
4f86d3a8 LB	43
	44	unsigned int flags;
	45	unsigned int exit_latency; /* in US */
02401c06	46	int power_usage; /* in mW */
4f86d3a8	47	unsigned int target_residency; /* in US */
cbc9ef02	48	bool disabled; /* disabled on all CPUs */
4f86d3a8	49
4f86d3a8	50	int (enter) (struct cpuidle_device dev,
46bcfad7	51	struct cpuidle_driver *drv,
e978aa7d	52	int index);
1a022e3f BO	53
1a022e3f BO	54	int (enter_dead) (struct cpuidle_device dev, int index);
4f86d3a8 LB	55	};
	56
	57	/* Idle State Flags */
	58	#define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */
4126c019	59	#define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */
b60e6a0e	60	#define CPUIDLE_FLAG_TIMER_STOP (0x04) /* timer is stopped on this state */
4f86d3a8 LB	61
	62	#define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000)
	63
4f86d3a8	64	struct cpuidle_device {
dcb84f33	65	unsigned int registered:1;
b5556a67	66	unsigned int enabled:1;
4f86d3a8 LB	67	unsigned int cpu;
	68
	69	int last_residency;
	70	int state_count;
4202735e	71	struct cpuidle_state_usage states_usage[CPUIDLE_STATE_MAX];
4f86d3a8	72	struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX];
bf4d1b5d	73	struct cpuidle_driver_kobj *kobj_driver;
4f86d3a8 LB	74	struct list_head device_list;
	75	struct kobject kobj;
	76	struct completion kobj_unregister;
4126c019 CC	77
	78	#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
	79	int safe_state_index;
	80	cpumask_t coupled_cpus;
	81	struct cpuidle_coupled *coupled;
	82	#endif
4f86d3a8 LB	83	};
	84
	85	DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices);
	86
	87	/**
	88	* cpuidle_get_last_residency - retrieves the last state's residency time
	89	* @dev: the target CPU
	90	*
	91	* NOTE: this value is invalid if CPUIDLE_FLAG_TIME_VALID isn't set
	92	*/
	93	static inline int cpuidle_get_last_residency(struct cpuidle_device *dev)
	94	{
	95	return dev->last_residency;
	96	}
	97
	98
	99	/****************************
	100	* CPUIDLE DRIVER INTERFACE *
	101	****************************/
	102
	103	struct cpuidle_driver {
db70b044	104	const char *name;
4f86d3a8	105	struct module *owner;
42f67f2a	106	int refcnt;
46bcfad7	107
e1689795 RL	108	/* set to 1 to use the core cpuidle time keeping (for all states). */
e1689795 RL	109	unsigned int en_core_tk_irqen:1;
8aef33a7	110	/* states array must be ordered in decreasing power consumption */
46bcfad7 DD	111	struct cpuidle_state states[CPUIDLE_STATE_MAX];
	112	int state_count;
	113	int safe_state_index;
4f86d3a8 LB	114	};
	115
	116	#ifdef CONFIG_CPU_IDLE
d91ee586	117	extern void disable_cpuidle(void);
a0bfa137	118	extern int cpuidle_idle_call(void);
4f86d3a8	119	extern int cpuidle_register_driver(struct cpuidle_driver *drv);
6e797a07 RW	120	extern struct cpuidle_driver *cpuidle_get_driver(void);
	121	extern struct cpuidle_driver *cpuidle_driver_ref(void);
	122	extern void cpuidle_driver_unref(void);
4f86d3a8 LB	123	extern void cpuidle_unregister_driver(struct cpuidle_driver *drv);
	124	extern int cpuidle_register_device(struct cpuidle_device *dev);
	125	extern void cpuidle_unregister_device(struct cpuidle_device *dev);
	126
	127	extern void cpuidle_pause_and_lock(void);
	128	extern void cpuidle_resume_and_unlock(void);
8651f97b PM	129	extern void cpuidle_pause(void);
8651f97b PM	130	extern void cpuidle_resume(void);
4f86d3a8 LB	131	extern int cpuidle_enable_device(struct cpuidle_device *dev);
4f86d3a8 LB	132	extern void cpuidle_disable_device(struct cpuidle_device *dev);
e1689795 RL	133	extern int cpuidle_wrap_enter(struct cpuidle_device *dev,
	134	struct cpuidle_driver *drv, int index,
	135	int (enter)(struct cpuidle_device dev,
	136	struct cpuidle_driver *drv, int index));
1a022e3f BO	137	extern int cpuidle_play_dead(void);
1a022e3f BO	138
bf4d1b5d DL	139	extern struct cpuidle_driver cpuidle_get_cpu_driver(struct cpuidle_device dev);
	140	extern int cpuidle_register_cpu_driver(struct cpuidle_driver *drv, int cpu);
	141	extern void cpuidle_unregister_cpu_driver(struct cpuidle_driver *drv, int cpu);
	142
4f86d3a8	143	#else
d91ee586	144	static inline void disable_cpuidle(void) { }
a0bfa137	145	static inline int cpuidle_idle_call(void) { return -ENODEV; }
4f86d3a8	146	static inline int cpuidle_register_driver(struct cpuidle_driver *drv)
6b2c676b	147	{return -ENODEV; }
752138df	148	static inline struct cpuidle_driver *cpuidle_get_driver(void) {return NULL; }
6e797a07 RW	149	static inline struct cpuidle_driver *cpuidle_driver_ref(void) {return NULL; }
6e797a07 RW	150	static inline void cpuidle_driver_unref(void) {}
4f86d3a8 LB	151	static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { }
4f86d3a8 LB	152	static inline int cpuidle_register_device(struct cpuidle_device *dev)
6b2c676b	153	{return -ENODEV; }
4f86d3a8 LB	154	static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { }
	155
	156	static inline void cpuidle_pause_and_lock(void) { }
	157	static inline void cpuidle_resume_and_unlock(void) { }
8651f97b PM	158	static inline void cpuidle_pause(void) { }
8651f97b PM	159	static inline void cpuidle_resume(void) { }
4f86d3a8	160	static inline int cpuidle_enable_device(struct cpuidle_device *dev)
6b2c676b	161	{return -ENODEV; }
4f86d3a8	162	static inline void cpuidle_disable_device(struct cpuidle_device *dev) { }
e1689795 RL	163	static inline int cpuidle_wrap_enter(struct cpuidle_device *dev,
	164	struct cpuidle_driver *drv, int index,
	165	int (enter)(struct cpuidle_device dev,
	166	struct cpuidle_driver *drv, int index))
	167	{ return -ENODEV; }
1a022e3f	168	static inline int cpuidle_play_dead(void) {return -ENODEV; }
4f86d3a8 LB	169	#endif
4f86d3a8 LB	170
20ff51a3 CC	171	#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
20ff51a3 CC	172	void cpuidle_coupled_parallel_barrier(struct cpuidle_device dev, atomic_t a);
c7a9b09b AB	173	#else
	174	static inline void cpuidle_coupled_parallel_barrier(struct cpuidle_device dev, atomic_t a)
	175	{
	176	}
20ff51a3 CC	177	#endif
20ff51a3 CC	178
4f86d3a8 LB	179	/******************************
	180	* CPUIDLE GOVERNOR INTERFACE *
	181	******************************/
	182
	183	struct cpuidle_governor {
	184	char name[CPUIDLE_NAME_LEN];
	185	struct list_head governor_list;
	186	unsigned int rating;
	187
46bcfad7 DD	188	int (enable) (struct cpuidle_driver drv,
	189	struct cpuidle_device *dev);
	190	void (disable) (struct cpuidle_driver drv,
	191	struct cpuidle_device *dev);
4f86d3a8	192
46bcfad7 DD	193	int (select) (struct cpuidle_driver drv,
46bcfad7 DD	194	struct cpuidle_device *dev);
e978aa7d	195	void (reflect) (struct cpuidle_device dev, int index);
4f86d3a8 LB	196
	197	struct module *owner;
	198	};
	199
	200	#ifdef CONFIG_CPU_IDLE
	201
	202	extern int cpuidle_register_governor(struct cpuidle_governor *gov);
	203	extern void cpuidle_unregister_governor(struct cpuidle_governor *gov);
	204
	205	#else
	206
	207	static inline int cpuidle_register_governor(struct cpuidle_governor *gov)
	208	{return 0;}
	209	static inline void cpuidle_unregister_governor(struct cpuidle_governor *gov) { }
	210
	211	#endif
	212
9a0b8415	213	#ifdef CONFIG_ARCH_HAS_CPU_RELAX
	214	#define CPUIDLE_DRIVER_STATE_START 1
	215	#else
	216	#define CPUIDLE_DRIVER_STATE_START 0
	217	#endif
	218
4f86d3a8	219	#endif /* _LINUX_CPUIDLE_H */