[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);
};

/* Idle State Flags */
#define CPUIDLE_FLAG_TIME_INVALID	(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_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;
	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 cpuidle_device_kobj *kobj_dev;
	struct list_head 	device_list;

#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);
DECLARE_PER_CPU(struct cpuidle_device, cpuidle_dev);

/**
 * cpuidle_get_last_residency - retrieves the last state's residency time
 * @dev: the target CPU
 *
 * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_INVALID is 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;

        /* 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 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 void cpuidle_use_deepest_state(bool enable);

extern struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev);
#else
static inline void disable_cpuidle(void) { }
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 void cpuidle_use_deepest_state(bool enable) {}
static inline struct cpuidle_driver *cpuidle_get_cpu_driver(
	struct cpuidle_device *dev) {return NULL; }
#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);
#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

#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);
4f86d3a8 LB	53	};
	54
	55	/* Idle State Flags */
b82b6cca	56	#define CPUIDLE_FLAG_TIME_INVALID (0x01) /* is residency time measurable? */
4126c019	57	#define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */
b60e6a0e	58	#define CPUIDLE_FLAG_TIMER_STOP (0x04) /* timer is stopped on this state */
4f86d3a8 LB	59
	60	#define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000)
	61
728ce22b	62	struct cpuidle_device_kobj;
1a706438 DL	63	struct cpuidle_state_kobj;
1a706438 DL	64	struct cpuidle_driver_kobj;
728ce22b	65
4f86d3a8	66	struct cpuidle_device {
dcb84f33	67	unsigned int registered:1;
b5556a67	68	unsigned int enabled:1;
4f86d3a8 LB	69	unsigned int cpu;
	70
	71	int last_residency;
	72	int state_count;
4202735e	73	struct cpuidle_state_usage states_usage[CPUIDLE_STATE_MAX];
4f86d3a8	74	struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX];
bf4d1b5d	75	struct cpuidle_driver_kobj *kobj_driver;
728ce22b	76	struct cpuidle_device_kobj *kobj_dev;
4f86d3a8	77	struct list_head device_list;
4126c019 CC	78
	79	#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
	80	int safe_state_index;
	81	cpumask_t coupled_cpus;
	82	struct cpuidle_coupled *coupled;
	83	#endif
4f86d3a8 LB	84	};
	85
	86	DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices);
f08dbf8a	87	DECLARE_PER_CPU(struct cpuidle_device, cpuidle_dev);
4f86d3a8 LB	88
	89	/**
	90	* cpuidle_get_last_residency - retrieves the last state's residency time
	91	* @dev: the target CPU
	92	*
b82b6cca	93	* NOTE: this value is invalid if CPUIDLE_FLAG_TIME_INVALID is set
4f86d3a8 LB	94	*/
	95	static inline int cpuidle_get_last_residency(struct cpuidle_device *dev)
	96	{
	97	return dev->last_residency;
	98	}
	99
	100
	101	/****************************
	102	* CPUIDLE DRIVER INTERFACE *
	103	****************************/
	104
	105	struct cpuidle_driver {
db70b044	106	const char *name;
4f86d3a8	107	struct module *owner;
42f67f2a	108	int refcnt;
46bcfad7	109
a06df062 DL	110	/* used by the cpuidle framework to setup the broadcast timer */
a06df062 DL	111	unsigned int bctimer:1;
8aef33a7	112	/* states array must be ordered in decreasing power consumption */
46bcfad7 DD	113	struct cpuidle_state states[CPUIDLE_STATE_MAX];
	114	int state_count;
	115	int safe_state_index;
82467a5a DL	116
82467a5a DL	117	/* the driver handles the cpus in cpumask */
6587fca2	118	struct cpumask *cpumask;
4f86d3a8 LB	119	};
	120
	121	#ifdef CONFIG_CPU_IDLE
d91ee586	122	extern void disable_cpuidle(void);
907e30f1	123
907e30f1 DL	124	extern int cpuidle_select(struct cpuidle_driver *drv,
	125	struct cpuidle_device *dev);
	126	extern int cpuidle_enter(struct cpuidle_driver *drv,
	127	struct cpuidle_device *dev, int index);
	128	extern void cpuidle_reflect(struct cpuidle_device *dev, int index);
	129
4f86d3a8	130	extern int cpuidle_register_driver(struct cpuidle_driver *drv);
6e797a07 RW	131	extern struct cpuidle_driver *cpuidle_get_driver(void);
	132	extern struct cpuidle_driver *cpuidle_driver_ref(void);
	133	extern void cpuidle_driver_unref(void);
4f86d3a8 LB	134	extern void cpuidle_unregister_driver(struct cpuidle_driver *drv);
	135	extern int cpuidle_register_device(struct cpuidle_device *dev);
	136	extern void cpuidle_unregister_device(struct cpuidle_device *dev);
4c637b21 DL	137	extern int cpuidle_register(struct cpuidle_driver *drv,
	138	const struct cpumask *const coupled_cpus);
	139	extern void cpuidle_unregister(struct cpuidle_driver *drv);
4f86d3a8 LB	140	extern void cpuidle_pause_and_lock(void);
4f86d3a8 LB	141	extern void cpuidle_resume_and_unlock(void);
8651f97b PM	142	extern void cpuidle_pause(void);
8651f97b PM	143	extern void cpuidle_resume(void);
4f86d3a8 LB	144	extern int cpuidle_enable_device(struct cpuidle_device *dev);
4f86d3a8 LB	145	extern void cpuidle_disable_device(struct cpuidle_device *dev);
1a022e3f	146	extern int cpuidle_play_dead(void);
a6220fc1	147	extern void cpuidle_use_deepest_state(bool enable);
1a022e3f	148
bf4d1b5d	149	extern struct cpuidle_driver cpuidle_get_cpu_driver(struct cpuidle_device dev);
4f86d3a8	150	#else
d91ee586	151	static inline void disable_cpuidle(void) { }
907e30f1 DL	152	static inline int cpuidle_select(struct cpuidle_driver *drv,
	153	struct cpuidle_device *dev)
	154	{return -ENODEV; }
	155	static inline int cpuidle_enter(struct cpuidle_driver *drv,
	156	struct cpuidle_device *dev, int index)
	157	{return -ENODEV; }
	158	static inline void cpuidle_reflect(struct cpuidle_device *dev, int index) { }
4f86d3a8	159	static inline int cpuidle_register_driver(struct cpuidle_driver *drv)
6b2c676b	160	{return -ENODEV; }
752138df	161	static inline struct cpuidle_driver *cpuidle_get_driver(void) {return NULL; }
6e797a07 RW	162	static inline struct cpuidle_driver *cpuidle_driver_ref(void) {return NULL; }
6e797a07 RW	163	static inline void cpuidle_driver_unref(void) {}
4f86d3a8 LB	164	static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { }
4f86d3a8 LB	165	static inline int cpuidle_register_device(struct cpuidle_device *dev)
6b2c676b	166	{return -ENODEV; }
4f86d3a8	167	static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { }
4c637b21 DL	168	static inline int cpuidle_register(struct cpuidle_driver *drv,
	169	const struct cpumask *const coupled_cpus)
	170	{return -ENODEV; }
	171	static inline void cpuidle_unregister(struct cpuidle_driver *drv) { }
4f86d3a8 LB	172	static inline void cpuidle_pause_and_lock(void) { }
4f86d3a8 LB	173	static inline void cpuidle_resume_and_unlock(void) { }
8651f97b PM	174	static inline void cpuidle_pause(void) { }
8651f97b PM	175	static inline void cpuidle_resume(void) { }
4f86d3a8	176	static inline int cpuidle_enable_device(struct cpuidle_device *dev)
6b2c676b	177	{return -ENODEV; }
4f86d3a8	178	static inline void cpuidle_disable_device(struct cpuidle_device *dev) { }
1a022e3f	179	static inline int cpuidle_play_dead(void) {return -ENODEV; }
a6220fc1	180	static inline void cpuidle_use_deepest_state(bool enable) {}
c8cc7d4d DL	181	static inline struct cpuidle_driver *cpuidle_get_cpu_driver(
c8cc7d4d DL	182	struct cpuidle_device *dev) {return NULL; }
4f86d3a8 LB	183	#endif
4f86d3a8 LB	184
20ff51a3 CC	185	#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
20ff51a3 CC	186	void cpuidle_coupled_parallel_barrier(struct cpuidle_device dev, atomic_t a);
c7a9b09b AB	187	#else
	188	static inline void cpuidle_coupled_parallel_barrier(struct cpuidle_device dev, atomic_t a)
	189	{
	190	}
20ff51a3 CC	191	#endif
20ff51a3 CC	192
4f86d3a8 LB	193	/******************************
	194	* CPUIDLE GOVERNOR INTERFACE *
	195	******************************/
	196
	197	struct cpuidle_governor {
	198	char name[CPUIDLE_NAME_LEN];
	199	struct list_head governor_list;
	200	unsigned int rating;
	201
46bcfad7 DD	202	int (enable) (struct cpuidle_driver drv,
	203	struct cpuidle_device *dev);
	204	void (disable) (struct cpuidle_driver drv,
	205	struct cpuidle_device *dev);
4f86d3a8	206
46bcfad7 DD	207	int (select) (struct cpuidle_driver drv,
46bcfad7 DD	208	struct cpuidle_device *dev);
e978aa7d	209	void (reflect) (struct cpuidle_device dev, int index);
4f86d3a8 LB	210
	211	struct module *owner;
	212	};
	213
	214	#ifdef CONFIG_CPU_IDLE
4f86d3a8	215	extern int cpuidle_register_governor(struct cpuidle_governor *gov);
4f86d3a8	216	#else
4f86d3a8 LB	217	static inline int cpuidle_register_governor(struct cpuidle_governor *gov)
4f86d3a8 LB	218	{return 0;}
4f86d3a8 LB	219	#endif
4f86d3a8 LB	220
9a0b8415	221	#ifdef CONFIG_ARCH_HAS_CPU_RELAX
	222	#define CPUIDLE_DRIVER_STATE_START 1
	223	#else
	224	#define CPUIDLE_DRIVER_STATE_START 0
	225	#endif
	226
4f86d3a8	227	#endif /* _LINUX_CPUIDLE_H */