[linux-2.6-block.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/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 *
 ****************************/

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);

	/*
	 * CPUs execute ->enter_freeze 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_freeze) (struct cpuidle_device *dev,
			      struct cpuidle_driver *drv,
			      int index);
};

/* Idle State Flags */
#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_kobj;
struct cpuidle_state_kobj;
struct cpuidle_driver_kobj;

struct cpuidle_device {
	unsigned int		registered:1;
	unsigned int		enabled:1;
	unsigned int		cpu;

	int			last_residency;
	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_get_last_residency - retrieves the last state's residency time
 * @dev: the target CPU
 */
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;

        /* 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;
};

#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);
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 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 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)
{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 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 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

#if defined(CONFIG_CPU_IDLE) && defined(CONFIG_SUSPEND)
extern int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
				      struct cpuidle_device *dev);
extern int cpuidle_enter_freeze(struct cpuidle_driver *drv,
				struct cpuidle_device *dev);
#else
static inline int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
					     struct cpuidle_device *dev)
{return -ENODEV; }
static inline int cpuidle_enter_freeze(struct cpuidle_driver *drv,
				       struct cpuidle_device *dev)
{return -ENODEV; }
#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

/******************************
 * 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);
#else
static inline int cpuidle_register_governor(struct cpuidle_governor *gov)
{return 0;}
#endif

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

#define CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx)	\
({								\
	int __ret;						\
								\
	if (!idx) {						\
		cpu_do_idle();					\
		return idx;					\
	}							\
								\
	__ret = cpu_pm_enter();					\
	if (!__ret) {						\
		__ret = low_level_idle_enter(idx);		\
		cpu_pm_exit();					\
	}							\
								\
	__ret ? -1 : idx;					\
})

#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>
e1689795	16	#include <linux/hrtimer.h>
4f86d3a8	17
86239ceb	18	#define CPUIDLE_STATE_MAX 10
4f86d3a8	19	#define CPUIDLE_NAME_LEN 16
4fcb2fcd	20	#define CPUIDLE_DESC_LEN 32
4f86d3a8	21
de477254 PG	22	struct module;
de477254 PG	23
4f86d3a8	24	struct cpuidle_device;
46bcfad7	25	struct cpuidle_driver;
4f86d3a8 LB	26
	27
	28	/****************************
	29	* CPUIDLE DEVICE INTERFACE *
	30	****************************/
	31
4202735e	32	struct cpuidle_state_usage {
dc7fd275	33	unsigned long long disable;
4202735e DD	34	unsigned long long usage;
	35	unsigned long long time; /* in US */
	36	};
	37
4f86d3a8 LB	38	struct cpuidle_state {
4f86d3a8 LB	39	char name[CPUIDLE_NAME_LEN];
4fcb2fcd	40	char desc[CPUIDLE_DESC_LEN];
4f86d3a8 LB	41
	42	unsigned int flags;
	43	unsigned int exit_latency; /* in US */
02401c06	44	int power_usage; /* in mW */
4f86d3a8	45	unsigned int target_residency; /* in US */
cbc9ef02	46	bool disabled; /* disabled on all CPUs */
4f86d3a8	47
4f86d3a8	48	int (enter) (struct cpuidle_device dev,
46bcfad7	49	struct cpuidle_driver *drv,
e978aa7d	50	int index);
1a022e3f BO	51
1a022e3f BO	52	int (enter_dead) (struct cpuidle_device dev, int index);
124cf911 RW	53
	54	/*
	55	* CPUs execute ->enter_freeze with the local tick or entire timekeeping
	56	* suspended, so it must not re-enable interrupts at any point (even
	57	* temporarily) or attempt to change states of clock event devices.
	58	*/
	59	void (enter_freeze) (struct cpuidle_device dev,
	60	struct cpuidle_driver *drv,
	61	int index);
4f86d3a8 LB	62	};
	63
	64	/* Idle State Flags */
4126c019	65	#define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */
b60e6a0e	66	#define CPUIDLE_FLAG_TIMER_STOP (0x04) /* timer is stopped on this state */
4f86d3a8 LB	67
	68	#define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000)
	69
728ce22b	70	struct cpuidle_device_kobj;
1a706438 DL	71	struct cpuidle_state_kobj;
1a706438 DL	72	struct cpuidle_driver_kobj;
728ce22b	73
4f86d3a8	74	struct cpuidle_device {
dcb84f33	75	unsigned int registered:1;
b5556a67	76	unsigned int enabled:1;
4f86d3a8 LB	77	unsigned int cpu;
	78
	79	int last_residency;
4202735e	80	struct cpuidle_state_usage states_usage[CPUIDLE_STATE_MAX];
4f86d3a8	81	struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX];
bf4d1b5d	82	struct cpuidle_driver_kobj *kobj_driver;
728ce22b	83	struct cpuidle_device_kobj *kobj_dev;
4f86d3a8	84	struct list_head device_list;
4126c019 CC	85
4126c019 CC	86	#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
4126c019 CC	87	cpumask_t coupled_cpus;
	88	struct cpuidle_coupled *coupled;
	89	#endif
4f86d3a8 LB	90	};
	91
	92	DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices);
f08dbf8a	93	DECLARE_PER_CPU(struct cpuidle_device, cpuidle_dev);
4f86d3a8 LB	94
	95	/**
	96	* cpuidle_get_last_residency - retrieves the last state's residency time
	97	* @dev: the target CPU
4f86d3a8 LB	98	*/
	99	static inline int cpuidle_get_last_residency(struct cpuidle_device *dev)
	100	{
	101	return dev->last_residency;
	102	}
	103
	104
	105	/****************************
	106	* CPUIDLE DRIVER INTERFACE *
	107	****************************/
	108
	109	struct cpuidle_driver {
db70b044	110	const char *name;
4f86d3a8	111	struct module *owner;
42f67f2a	112	int refcnt;
46bcfad7	113
a06df062 DL	114	/* used by the cpuidle framework to setup the broadcast timer */
a06df062 DL	115	unsigned int bctimer:1;
8aef33a7	116	/* states array must be ordered in decreasing power consumption */
46bcfad7 DD	117	struct cpuidle_state states[CPUIDLE_STATE_MAX];
	118	int state_count;
	119	int safe_state_index;
82467a5a DL	120
82467a5a DL	121	/* the driver handles the cpus in cpumask */
6587fca2	122	struct cpumask *cpumask;
4f86d3a8 LB	123	};
	124
	125	#ifdef CONFIG_CPU_IDLE
d91ee586	126	extern void disable_cpuidle(void);
ef2b22ac RW	127	extern bool cpuidle_not_available(struct cpuidle_driver *drv,
ef2b22ac RW	128	struct cpuidle_device *dev);
907e30f1	129
907e30f1 DL	130	extern int cpuidle_select(struct cpuidle_driver *drv,
	131	struct cpuidle_device *dev);
	132	extern int cpuidle_enter(struct cpuidle_driver *drv,
	133	struct cpuidle_device *dev, int index);
	134	extern void cpuidle_reflect(struct cpuidle_device *dev, int index);
	135
4f86d3a8	136	extern int cpuidle_register_driver(struct cpuidle_driver *drv);
6e797a07 RW	137	extern struct cpuidle_driver *cpuidle_get_driver(void);
	138	extern struct cpuidle_driver *cpuidle_driver_ref(void);
	139	extern void cpuidle_driver_unref(void);
4f86d3a8 LB	140	extern void cpuidle_unregister_driver(struct cpuidle_driver *drv);
	141	extern int cpuidle_register_device(struct cpuidle_device *dev);
	142	extern void cpuidle_unregister_device(struct cpuidle_device *dev);
4c637b21 DL	143	extern int cpuidle_register(struct cpuidle_driver *drv,
	144	const struct cpumask *const coupled_cpus);
	145	extern void cpuidle_unregister(struct cpuidle_driver *drv);
4f86d3a8 LB	146	extern void cpuidle_pause_and_lock(void);
4f86d3a8 LB	147	extern void cpuidle_resume_and_unlock(void);
8651f97b PM	148	extern void cpuidle_pause(void);
8651f97b PM	149	extern void cpuidle_resume(void);
4f86d3a8 LB	150	extern int cpuidle_enable_device(struct cpuidle_device *dev);
4f86d3a8 LB	151	extern void cpuidle_disable_device(struct cpuidle_device *dev);
1a022e3f BO	152	extern int cpuidle_play_dead(void);
1a022e3f BO	153
bf4d1b5d	154	extern struct cpuidle_driver cpuidle_get_cpu_driver(struct cpuidle_device dev);
9bd616e3 CM	155	static inline struct cpuidle_device *cpuidle_get_device(void)
9bd616e3 CM	156	{return __this_cpu_read(cpuidle_devices); }
4f86d3a8	157	#else
d91ee586	158	static inline void disable_cpuidle(void) { }
ef2b22ac RW	159	static inline bool cpuidle_not_available(struct cpuidle_driver *drv,
	160	struct cpuidle_device *dev)
	161	{return true; }
907e30f1 DL	162	static inline int cpuidle_select(struct cpuidle_driver *drv,
	163	struct cpuidle_device *dev)
	164	{return -ENODEV; }
	165	static inline int cpuidle_enter(struct cpuidle_driver *drv,
	166	struct cpuidle_device *dev, int index)
	167	{return -ENODEV; }
	168	static inline void cpuidle_reflect(struct cpuidle_device *dev, int index) { }
4f86d3a8	169	static inline int cpuidle_register_driver(struct cpuidle_driver *drv)
6b2c676b	170	{return -ENODEV; }
752138df	171	static inline struct cpuidle_driver *cpuidle_get_driver(void) {return NULL; }
6e797a07 RW	172	static inline struct cpuidle_driver *cpuidle_driver_ref(void) {return NULL; }
6e797a07 RW	173	static inline void cpuidle_driver_unref(void) {}
4f86d3a8 LB	174	static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { }
4f86d3a8 LB	175	static inline int cpuidle_register_device(struct cpuidle_device *dev)
6b2c676b	176	{return -ENODEV; }
4f86d3a8	177	static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { }
4c637b21 DL	178	static inline int cpuidle_register(struct cpuidle_driver *drv,
	179	const struct cpumask *const coupled_cpus)
	180	{return -ENODEV; }
	181	static inline void cpuidle_unregister(struct cpuidle_driver *drv) { }
4f86d3a8 LB	182	static inline void cpuidle_pause_and_lock(void) { }
4f86d3a8 LB	183	static inline void cpuidle_resume_and_unlock(void) { }
8651f97b PM	184	static inline void cpuidle_pause(void) { }
8651f97b PM	185	static inline void cpuidle_resume(void) { }
4f86d3a8	186	static inline int cpuidle_enable_device(struct cpuidle_device *dev)
6b2c676b	187	{return -ENODEV; }
4f86d3a8	188	static inline void cpuidle_disable_device(struct cpuidle_device *dev) { }
1a022e3f	189	static inline int cpuidle_play_dead(void) {return -ENODEV; }
87e9b9f1 RW	190	static inline struct cpuidle_driver *cpuidle_get_cpu_driver(
87e9b9f1 RW	191	struct cpuidle_device *dev) {return NULL; }
9bd616e3	192	static inline struct cpuidle_device *cpuidle_get_device(void) {return NULL; }
87e9b9f1 RW	193	#endif
	194
	195	#if defined(CONFIG_CPU_IDLE) && defined(CONFIG_SUSPEND)
	196	extern int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
	197	struct cpuidle_device *dev);
	198	extern int cpuidle_enter_freeze(struct cpuidle_driver *drv,
	199	struct cpuidle_device *dev);
	200	#else
ef2b22ac RW	201	static inline int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
	202	struct cpuidle_device *dev)
	203	{return -ENODEV; }
	204	static inline int cpuidle_enter_freeze(struct cpuidle_driver *drv,
	205	struct cpuidle_device *dev)
	206	{return -ENODEV; }
4f86d3a8 LB	207	#endif
4f86d3a8 LB	208
faad3849 RW	209	/* kernel/sched/idle.c */
faad3849 RW	210	extern void sched_idle_set_state(struct cpuidle_state *idle_state);
827a5aef	211	extern void default_idle_call(void);
faad3849	212
20ff51a3 CC	213	#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
20ff51a3 CC	214	void cpuidle_coupled_parallel_barrier(struct cpuidle_device dev, atomic_t a);
c7a9b09b AB	215	#else
	216	static inline void cpuidle_coupled_parallel_barrier(struct cpuidle_device dev, atomic_t a)
	217	{
	218	}
20ff51a3 CC	219	#endif
20ff51a3 CC	220
4f86d3a8 LB	221	/******************************
	222	* CPUIDLE GOVERNOR INTERFACE *
	223	******************************/
	224
	225	struct cpuidle_governor {
	226	char name[CPUIDLE_NAME_LEN];
	227	struct list_head governor_list;
	228	unsigned int rating;
	229
46bcfad7 DD	230	int (enable) (struct cpuidle_driver drv,
	231	struct cpuidle_device *dev);
	232	void (disable) (struct cpuidle_driver drv,
	233	struct cpuidle_device *dev);
4f86d3a8	234
46bcfad7 DD	235	int (select) (struct cpuidle_driver drv,
46bcfad7 DD	236	struct cpuidle_device *dev);
e978aa7d	237	void (reflect) (struct cpuidle_device dev, int index);
4f86d3a8 LB	238
	239	struct module *owner;
	240	};
	241
	242	#ifdef CONFIG_CPU_IDLE
4f86d3a8	243	extern int cpuidle_register_governor(struct cpuidle_governor *gov);
4f86d3a8	244	#else
4f86d3a8 LB	245	static inline int cpuidle_register_governor(struct cpuidle_governor *gov)
4f86d3a8 LB	246	{return 0;}
4f86d3a8 LB	247	#endif
4f86d3a8 LB	248
9a0b8415	249	#ifdef CONFIG_ARCH_HAS_CPU_RELAX
	250	#define CPUIDLE_DRIVER_STATE_START 1
	251	#else
	252	#define CPUIDLE_DRIVER_STATE_START 0
	253	#endif
	254
220276e0 SH	255	#define CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx) \
	256	({ \
	257	int __ret; \
	258	\
	259	if (!idx) { \
	260	cpu_do_idle(); \
	261	return idx; \
	262	} \
	263	\
	264	__ret = cpu_pm_enter(); \
	265	if (!__ret) { \
	266	__ret = low_level_idle_enter(idx); \
	267	cpu_pm_exit(); \
	268	} \
	269	\
	270	__ret ? -1 : idx; \
	271	})
	272
4f86d3a8	273	#endif /* _LINUX_CPUIDLE_H */