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

/*
 * linux/include/linux/cpufreq.h
 *
 * Copyright (C) 2001 Russell King
 *           (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#ifndef _LINUX_CPUFREQ_H
#define _LINUX_CPUFREQ_H

#include <linux/cpumask.h>
#include <linux/completion.h>
#include <linux/kobject.h>
#include <linux/notifier.h>
#include <linux/sysfs.h>

/*********************************************************************
 *                        CPUFREQ INTERFACE                          *
 *********************************************************************/
/*
 * Frequency values here are CPU kHz
 *
 * Maximum transition latency is in nanoseconds - if it's unknown,
 * CPUFREQ_ETERNAL shall be used.
 */

#define CPUFREQ_ETERNAL			(-1)
#define CPUFREQ_NAME_LEN		16
/* Print length for names. Extra 1 space for accomodating '\n' in prints */
#define CPUFREQ_NAME_PLEN		(CPUFREQ_NAME_LEN + 1)

struct cpufreq_governor;

struct cpufreq_freqs {
	unsigned int cpu;	/* cpu nr */
	unsigned int old;
	unsigned int new;
	u8 flags;		/* flags of cpufreq_driver, see below. */
};

struct cpufreq_cpuinfo {
	unsigned int		max_freq;
	unsigned int		min_freq;

	/* in 10^(-9) s = nanoseconds */
	unsigned int		transition_latency;
};

struct cpufreq_real_policy {
	unsigned int		min;    /* in kHz */
	unsigned int		max;    /* in kHz */
	unsigned int		policy; /* see above */
	struct cpufreq_governor	*governor; /* see below */
};

struct cpufreq_policy {
	/* CPUs sharing clock, require sw coordination */
	cpumask_var_t		cpus;	/* Online CPUs only */
	cpumask_var_t		related_cpus; /* Online + Offline CPUs */

	unsigned int		shared_type; /* ACPI: ANY or ALL affected CPUs
						should set cpufreq */
	unsigned int		cpu;    /* cpu nr of CPU managing this policy */
	unsigned int		last_cpu; /* cpu nr of previous CPU that managed
					   * this policy */
	struct cpufreq_cpuinfo	cpuinfo;/* see above */

	unsigned int		min;    /* in kHz */
	unsigned int		max;    /* in kHz */
	unsigned int		cur;    /* in kHz, only needed if cpufreq
					 * governors are used */
	unsigned int		policy; /* see above */
	struct cpufreq_governor	*governor; /* see below */
	void			*governor_data;
	bool			governor_enabled; /* governor start/stop flag */

	struct work_struct	update; /* if update_policy() needs to be
					 * called, but you're in IRQ context */

	struct cpufreq_real_policy	user_policy;

	struct list_head        policy_list;
	struct kobject		kobj;
	struct completion	kobj_unregister;
};

/* Only for ACPI */
#define CPUFREQ_SHARED_TYPE_NONE (0) /* None */
#define CPUFREQ_SHARED_TYPE_HW	 (1) /* HW does needed coordination */
#define CPUFREQ_SHARED_TYPE_ALL	 (2) /* All dependent CPUs should set freq */
#define CPUFREQ_SHARED_TYPE_ANY	 (3) /* Freq can be set from any dependent CPU*/

struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu);
void cpufreq_cpu_put(struct cpufreq_policy *policy);

static inline bool policy_is_shared(struct cpufreq_policy *policy)
{
	return cpumask_weight(policy->cpus) > 1;
}

/* /sys/devices/system/cpu/cpufreq: entry point for global variables */
extern struct kobject *cpufreq_global_kobject;
int cpufreq_get_global_kobject(void);
void cpufreq_put_global_kobject(void);
int cpufreq_sysfs_create_file(const struct attribute *attr);
void cpufreq_sysfs_remove_file(const struct attribute *attr);

#ifdef CONFIG_CPU_FREQ
unsigned int cpufreq_get(unsigned int cpu);
unsigned int cpufreq_quick_get(unsigned int cpu);
unsigned int cpufreq_quick_get_max(unsigned int cpu);
void disable_cpufreq(void);

u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy);
int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu);
int cpufreq_update_policy(unsigned int cpu);
bool have_governor_per_policy(void);
struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy);
#else
static inline unsigned int cpufreq_get(unsigned int cpu)
{
	return 0;
}
static inline unsigned int cpufreq_quick_get(unsigned int cpu)
{
	return 0;
}
static inline unsigned int cpufreq_quick_get_max(unsigned int cpu)
{
	return 0;
}
static inline void disable_cpufreq(void) { }
#endif

/*********************************************************************
 *                      CPUFREQ DRIVER INTERFACE                     *
 *********************************************************************/

#define CPUFREQ_RELATION_L 0  /* lowest frequency at or above target */
#define CPUFREQ_RELATION_H 1  /* highest frequency below or at target */

struct freq_attr {
	struct attribute attr;
	ssize_t (*show)(struct cpufreq_policy *, char *);
	ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count);
};

#define cpufreq_freq_attr_ro(_name)		\
static struct freq_attr _name =			\
__ATTR(_name, 0444, show_##_name, NULL)

#define cpufreq_freq_attr_ro_perm(_name, _perm)	\
static struct freq_attr _name =			\
__ATTR(_name, _perm, show_##_name, NULL)

#define cpufreq_freq_attr_rw(_name)		\
static struct freq_attr _name =			\
__ATTR(_name, 0644, show_##_name, store_##_name)

struct global_attr {
	struct attribute attr;
	ssize_t (*show)(struct kobject *kobj,
			struct attribute *attr, char *buf);
	ssize_t (*store)(struct kobject *a, struct attribute *b,
			 const char *c, size_t count);
};

#define define_one_global_ro(_name)		\
static struct global_attr _name =		\
__ATTR(_name, 0444, show_##_name, NULL)

#define define_one_global_rw(_name)		\
static struct global_attr _name =		\
__ATTR(_name, 0644, show_##_name, store_##_name)


struct cpufreq_driver {
	char			name[CPUFREQ_NAME_LEN];
	u8			flags;
	/*
	 * This should be set by platforms having multiple clock-domains, i.e.
	 * supporting multiple policies. With this sysfs directories of governor
	 * would be created in cpu/cpu<num>/cpufreq/ directory and so they can
	 * use the same governor with different tunables for different clusters.
	 */
	bool			have_governor_per_policy;

	/* needed by all drivers */
	int	(*init)		(struct cpufreq_policy *policy);
	int	(*verify)	(struct cpufreq_policy *policy);

	/* define one out of two */
	int	(*setpolicy)	(struct cpufreq_policy *policy);
	int	(*target)	(struct cpufreq_policy *policy,
				 unsigned int target_freq,
				 unsigned int relation);

	/* should be defined, if possible */
	unsigned int	(*get)	(unsigned int cpu);

	/* optional */
	int	(*bios_limit)	(int cpu, unsigned int *limit);

	int	(*exit)		(struct cpufreq_policy *policy);
	int	(*suspend)	(struct cpufreq_policy *policy);
	int	(*resume)	(struct cpufreq_policy *policy);
	struct freq_attr	**attr;
};

/* flags */
#define CPUFREQ_STICKY		0x01	/* the driver isn't removed even if
					 * all ->init() calls failed */
#define CPUFREQ_CONST_LOOPS	0x02	/* loops_per_jiffy or other kernel
					 * "constants" aren't affected by
					 * frequency transitions */
#define CPUFREQ_PM_NO_WARN	0x04	/* don't warn on suspend/resume speed
					 * mismatches */

int cpufreq_register_driver(struct cpufreq_driver *driver_data);
int cpufreq_unregister_driver(struct cpufreq_driver *driver_data);

const char *cpufreq_get_current_driver(void);

static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy,
		unsigned int min, unsigned int max)
{
	if (policy->min < min)
		policy->min = min;
	if (policy->max < min)
		policy->max = min;
	if (policy->min > max)
		policy->min = max;
	if (policy->max > max)
		policy->max = max;
	if (policy->min > policy->max)
		policy->min = policy->max;
	return;
}

/*********************************************************************
 *                     CPUFREQ NOTIFIER INTERFACE                    *
 *********************************************************************/

#define CPUFREQ_TRANSITION_NOTIFIER	(0)
#define CPUFREQ_POLICY_NOTIFIER		(1)

/* Transition notifiers */
#define CPUFREQ_PRECHANGE		(0)
#define CPUFREQ_POSTCHANGE		(1)
#define CPUFREQ_RESUMECHANGE		(8)
#define CPUFREQ_SUSPENDCHANGE		(9)

/* Policy Notifiers  */
#define CPUFREQ_ADJUST			(0)
#define CPUFREQ_INCOMPATIBLE		(1)
#define CPUFREQ_NOTIFY			(2)
#define CPUFREQ_START			(3)
#define CPUFREQ_UPDATE_POLICY_CPU	(4)

#ifdef CONFIG_CPU_FREQ
int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list);
int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list);

void cpufreq_notify_transition(struct cpufreq_policy *policy,
		struct cpufreq_freqs *freqs, unsigned int state);

#else /* CONFIG_CPU_FREQ */
static inline int cpufreq_register_notifier(struct notifier_block *nb,
						unsigned int list)
{
	return 0;
}
static inline int cpufreq_unregister_notifier(struct notifier_block *nb,
						unsigned int list)
{
	return 0;
}
#endif /* !CONFIG_CPU_FREQ */

/**
 * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch
 * safe)
 * @old:   old value
 * @div:   divisor
 * @mult:  multiplier
 *
 *
 * new = old * mult / div
 */
static inline unsigned long cpufreq_scale(unsigned long old, u_int div,
		u_int mult)
{
#if BITS_PER_LONG == 32
	u64 result = ((u64) old) * ((u64) mult);
	do_div(result, div);
	return (unsigned long) result;

#elif BITS_PER_LONG == 64
	unsigned long result = old * ((u64) mult);
	result /= div;
	return result;
#endif
}

/*********************************************************************
 *                          CPUFREQ GOVERNORS                        *
 *********************************************************************/

/*
 * If (cpufreq_driver->target) exists, the ->governor decides what frequency
 * within the limits is used. If (cpufreq_driver->setpolicy> exists, these
 * two generic policies are available:
 */
#define CPUFREQ_POLICY_POWERSAVE	(1)
#define CPUFREQ_POLICY_PERFORMANCE	(2)

/* Governor Events */
#define CPUFREQ_GOV_START	1
#define CPUFREQ_GOV_STOP	2
#define CPUFREQ_GOV_LIMITS	3
#define CPUFREQ_GOV_POLICY_INIT	4
#define CPUFREQ_GOV_POLICY_EXIT	5

struct cpufreq_governor {
	char	name[CPUFREQ_NAME_LEN];
	int	initialized;
	int	(*governor)	(struct cpufreq_policy *policy,
				 unsigned int event);
	ssize_t	(*show_setspeed)	(struct cpufreq_policy *policy,
					 char *buf);
	int	(*store_setspeed)	(struct cpufreq_policy *policy,
					 unsigned int freq);
	unsigned int max_transition_latency; /* HW must be able to switch to
			next freq faster than this value in nano secs or we
			will fallback to performance governor */
	struct list_head	governor_list;
	struct module		*owner;
};

/* Pass a target to the cpufreq driver */
int cpufreq_driver_target(struct cpufreq_policy *policy,
				 unsigned int target_freq,
				 unsigned int relation);
int __cpufreq_driver_target(struct cpufreq_policy *policy,
				   unsigned int target_freq,
				   unsigned int relation);
int cpufreq_register_governor(struct cpufreq_governor *governor);
void cpufreq_unregister_governor(struct cpufreq_governor *governor);

/* CPUFREQ DEFAULT GOVERNOR */
/*
 * Performance governor is fallback governor if any other gov failed to auto
 * load due latency restrictions
 */
#ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE
extern struct cpufreq_governor cpufreq_gov_performance;
#endif
#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
#define CPUFREQ_DEFAULT_GOVERNOR	(&cpufreq_gov_performance)
#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE)
extern struct cpufreq_governor cpufreq_gov_powersave;
#define CPUFREQ_DEFAULT_GOVERNOR	(&cpufreq_gov_powersave)
#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE)
extern struct cpufreq_governor cpufreq_gov_userspace;
#define CPUFREQ_DEFAULT_GOVERNOR	(&cpufreq_gov_userspace)
#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND)
extern struct cpufreq_governor cpufreq_gov_ondemand;
#define CPUFREQ_DEFAULT_GOVERNOR	(&cpufreq_gov_ondemand)
#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE)
extern struct cpufreq_governor cpufreq_gov_conservative;
#define CPUFREQ_DEFAULT_GOVERNOR	(&cpufreq_gov_conservative)
#endif

/*********************************************************************
 *                     FREQUENCY TABLE HELPERS                       *
 *********************************************************************/

#define CPUFREQ_ENTRY_INVALID ~0
#define CPUFREQ_TABLE_END     ~1

struct cpufreq_frequency_table {
	unsigned int	driver_data; /* driver specific data, not used by core */
	unsigned int	frequency; /* kHz - doesn't need to be in ascending
				    * order */
};

int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
				    struct cpufreq_frequency_table *table);

int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
				   struct cpufreq_frequency_table *table);

int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
				   struct cpufreq_frequency_table *table,
				   unsigned int target_freq,
				   unsigned int relation,
				   unsigned int *index);

void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy);
ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf);

/* the following funtion is for cpufreq core use only */
struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu);

/* the following are really really optional */
extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs;
void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
				      unsigned int cpu);
void cpufreq_frequency_table_put_attr(unsigned int cpu);

#endif /* _LINUX_CPUFREQ_H */
Commit	Line	Data
1da177e4	1	/*
bb176f7d	2	* linux/include/linux/cpufreq.h
1da177e4	3	*
bb176f7d VK	4	* Copyright (C) 2001 Russell King
bb176f7d VK	5	* (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
335dc333	6	*
1da177e4 LT	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*/
	11	#ifndef _LINUX_CPUFREQ_H
	12	#define _LINUX_CPUFREQ_H
	13
5ff0a268 VK	14	#include <linux/cpumask.h>
5ff0a268 VK	15	#include <linux/completion.h>
1da177e4	16	#include <linux/kobject.h>
5ff0a268	17	#include <linux/notifier.h>
1da177e4	18	#include <linux/sysfs.h>
1da177e4	19
1da177e4	20	/*********************************************************************
74aca95d	21	* CPUFREQ INTERFACE *
1da177e4	22	*********************************************************************/
74aca95d VK	23	/*
	24	* Frequency values here are CPU kHz
	25	*
b53cc6ea	26	* Maximum transition latency is in nanoseconds - if it's unknown,
1da177e4 LT	27	* CPUFREQ_ETERNAL shall be used.
	28	*/
	29
74aca95d VK	30	#define CPUFREQ_ETERNAL (-1)
	31	#define CPUFREQ_NAME_LEN 16
	32	/* Print length for names. Extra 1 space for accomodating '\n' in prints */
	33	#define CPUFREQ_NAME_PLEN (CPUFREQ_NAME_LEN + 1)
	34
1da177e4 LT	35	struct cpufreq_governor;
1da177e4 LT	36
74aca95d VK	37	struct cpufreq_freqs {
	38	unsigned int cpu; /* cpu nr */
	39	unsigned int old;
	40	unsigned int new;
	41	u8 flags; /* flags of cpufreq_driver, see below. */
	42	};
8aa84ad8	43
1da177e4 LT	44	struct cpufreq_cpuinfo {
	45	unsigned int max_freq;
	46	unsigned int min_freq;
335dc333 TF	47
	48	/* in 10^(-9) s = nanoseconds */
	49	unsigned int transition_latency;
1da177e4 LT	50	};
	51
	52	struct cpufreq_real_policy {
	53	unsigned int min; /* in kHz */
	54	unsigned int max; /* in kHz */
335dc333	55	unsigned int policy; /* see above */
1da177e4 LT	56	struct cpufreq_governor governor; / see below */
	57	};
	58
	59	struct cpufreq_policy {
951fc5f4 VK	60	/* CPUs sharing clock, require sw coordination */
	61	cpumask_var_t cpus; /* Online CPUs only */
	62	cpumask_var_t related_cpus; /* Online + Offline CPUs */
	63
62b36cc1	64	unsigned int shared_type; /* ACPI: ANY or ALL affected CPUs
3b2d9942	65	should set cpufreq */
b8eed8af VK	66	unsigned int cpu; /* cpu nr of CPU managing this policy */
	67	unsigned int last_cpu; /* cpu nr of previous CPU that managed
	68	* this policy */
1da177e4 LT	69	struct cpufreq_cpuinfo cpuinfo;/* see above */
	70
	71	unsigned int min; /* in kHz */
	72	unsigned int max; /* in kHz */
	73	unsigned int cur; /* in kHz, only needed if cpufreq
	74	* governors are used */
335dc333	75	unsigned int policy; /* see above */
1da177e4	76	struct cpufreq_governor governor; / see below */
7bd353a9	77	void *governor_data;
95731ebb	78	bool governor_enabled; /* governor start/stop flag */
1da177e4	79
1da177e4 LT	80	struct work_struct update; /* if update_policy() needs to be
	81	* called, but you're in IRQ context */
	82
	83	struct cpufreq_real_policy user_policy;
	84
c88a1f8b	85	struct list_head policy_list;
1da177e4 LT	86	struct kobject kobj;
	87	struct completion kobj_unregister;
	88	};
	89
62b36cc1	90	/* Only for ACPI */
46f18e3a VP	91	#define CPUFREQ_SHARED_TYPE_NONE (0) /* None */
	92	#define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */
	93	#define CPUFREQ_SHARED_TYPE_ALL (2) /* All dependent CPUs should set freq */
	94	#define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/
1da177e4	95
74aca95d	96	struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu);
3a3e9e06	97	void cpufreq_cpu_put(struct cpufreq_policy *policy);
74aca95d	98
2624f90c FB	99	static inline bool policy_is_shared(struct cpufreq_policy *policy)
	100	{
	101	return cpumask_weight(policy->cpus) > 1;
	102	}
	103
74aca95d VK	104	/* /sys/devices/system/cpu/cpufreq: entry point for global variables */
	105	extern struct kobject *cpufreq_global_kobject;
	106	int cpufreq_get_global_kobject(void);
	107	void cpufreq_put_global_kobject(void);
	108	int cpufreq_sysfs_create_file(const struct attribute *attr);
	109	void cpufreq_sysfs_remove_file(const struct attribute *attr);
1da177e4	110
74aca95d VK	111	#ifdef CONFIG_CPU_FREQ
	112	unsigned int cpufreq_get(unsigned int cpu);
	113	unsigned int cpufreq_quick_get(unsigned int cpu);
	114	unsigned int cpufreq_quick_get_max(unsigned int cpu);
	115	void disable_cpufreq(void);
1da177e4	116
74aca95d VK	117	u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy);
	118	int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu);
	119	int cpufreq_update_policy(unsigned int cpu);
	120	bool have_governor_per_policy(void);
	121	struct kobject get_governor_parent_kobj(struct cpufreq_policy policy);
	122	#else
	123	static inline unsigned int cpufreq_get(unsigned int cpu)
1da177e4	124	{
74aca95d VK	125	return 0;
	126	}
	127	static inline unsigned int cpufreq_quick_get(unsigned int cpu)
	128	{
	129	return 0;
	130	}
	131	static inline unsigned int cpufreq_quick_get_max(unsigned int cpu)
	132	{
	133	return 0;
	134	}
	135	static inline void disable_cpufreq(void) { }
1da177e4	136	#endif
1da177e4 LT	137
1da177e4 LT	138	/*********************************************************************
74aca95d	139	* CPUFREQ DRIVER INTERFACE *
1da177e4 LT	140	*********************************************************************/
1da177e4 LT	141
74aca95d VK	142	#define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */
74aca95d VK	143	#define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */
1da177e4	144
74aca95d VK	145	struct freq_attr {
	146	struct attribute attr;
	147	ssize_t (show)(struct cpufreq_policy , char *);
	148	ssize_t (store)(struct cpufreq_policy , const char *, size_t count);
1da177e4 LT	149	};
1da177e4 LT	150
74aca95d VK	151	#define cpufreq_freq_attr_ro(_name) \
	152	static struct freq_attr _name = \
	153	__ATTR(_name, 0444, show_##_name, NULL)
1da177e4	154
74aca95d VK	155	#define cpufreq_freq_attr_ro_perm(_name, _perm) \
	156	static struct freq_attr _name = \
	157	__ATTR(_name, _perm, show_##_name, NULL)
1da177e4	158
74aca95d VK	159	#define cpufreq_freq_attr_rw(_name) \
	160	static struct freq_attr _name = \
	161	__ATTR(_name, 0644, show_##_name, store_##_name)
	162
	163	struct global_attr {
	164	struct attribute attr;
	165	ssize_t (show)(struct kobject kobj,
	166	struct attribute attr, char buf);
	167	ssize_t (store)(struct kobject a, struct attribute *b,
	168	const char *c, size_t count);
	169	};
	170
	171	#define define_one_global_ro(_name) \
	172	static struct global_attr _name = \
	173	__ATTR(_name, 0444, show_##_name, NULL)
	174
	175	#define define_one_global_rw(_name) \
	176	static struct global_attr _name = \
	177	__ATTR(_name, 0644, show_##_name, store_##_name)
1da177e4	178
1da177e4 LT	179
1da177e4 LT	180	struct cpufreq_driver {
1da177e4 LT	181	char name[CPUFREQ_NAME_LEN];
1da177e4 LT	182	u8 flags;
4d5dcc42 VK	183	/*
	184	* This should be set by platforms having multiple clock-domains, i.e.
	185	* supporting multiple policies. With this sysfs directories of governor
	186	* would be created in cpu/cpu<num>/cpufreq/ directory and so they can
	187	* use the same governor with different tunables for different clusters.
	188	*/
	189	bool have_governor_per_policy;
1da177e4 LT	190
	191	/* needed by all drivers */
	192	int (init) (struct cpufreq_policy policy);
	193	int (verify) (struct cpufreq_policy policy);
	194
	195	/* define one out of two */
	196	int (setpolicy) (struct cpufreq_policy policy);
	197	int (target) (struct cpufreq_policy policy,
	198	unsigned int target_freq,
	199	unsigned int relation);
	200
	201	/* should be defined, if possible */
	202	unsigned int (*get) (unsigned int cpu);
	203
	204	/* optional */
e2f74f35	205	int (bios_limit) (int cpu, unsigned int limit);
bf0b90e3	206
1da177e4	207	int (exit) (struct cpufreq_policy policy);
7ca64e2d	208	int (suspend) (struct cpufreq_policy policy);
1da177e4 LT	209	int (resume) (struct cpufreq_policy policy);
	210	struct freq_attr **attr;
	211	};
	212
	213	/* flags */
335dc333	214	#define CPUFREQ_STICKY 0x01 /* the driver isn't removed even if
1da177e4	215	* all ->init() calls failed */
335dc333	216	#define CPUFREQ_CONST_LOOPS 0x02 /* loops_per_jiffy or other kernel
1da177e4 LT	217	* "constants" aren't affected by
1da177e4 LT	218	* frequency transitions */
42d4dc3f BH	219	#define CPUFREQ_PM_NO_WARN 0x04 /* don't warn on suspend/resume speed
42d4dc3f BH	220	* mismatches */
1da177e4	221
221dee28 LT	222	int cpufreq_register_driver(struct cpufreq_driver *driver_data);
221dee28 LT	223	int cpufreq_unregister_driver(struct cpufreq_driver *driver_data);
1da177e4	224
74aca95d	225	const char *cpufreq_get_current_driver(void);
1da177e4	226
bb176f7d VK	227	static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy,
bb176f7d VK	228	unsigned int min, unsigned int max)
1da177e4 LT	229	{
	230	if (policy->min < min)
	231	policy->min = min;
	232	if (policy->max < min)
	233	policy->max = min;
	234	if (policy->min > max)
	235	policy->min = max;
	236	if (policy->max > max)
	237	policy->max = max;
	238	if (policy->min > policy->max)
	239	policy->min = policy->max;
	240	return;
	241	}
	242
74aca95d VK	243	/*********************************************************************
	244	* CPUFREQ NOTIFIER INTERFACE *
	245	*********************************************************************/
6dad2a29	246
74aca95d VK	247	#define CPUFREQ_TRANSITION_NOTIFIER (0)
74aca95d VK	248	#define CPUFREQ_POLICY_NOTIFIER (1)
1da177e4	249
74aca95d VK	250	/* Transition notifiers */
	251	#define CPUFREQ_PRECHANGE (0)
	252	#define CPUFREQ_POSTCHANGE (1)
	253	#define CPUFREQ_RESUMECHANGE (8)
	254	#define CPUFREQ_SUSPENDCHANGE (9)
6dad2a29	255
74aca95d VK	256	/* Policy Notifiers */
	257	#define CPUFREQ_ADJUST (0)
	258	#define CPUFREQ_INCOMPATIBLE (1)
	259	#define CPUFREQ_NOTIFY (2)
	260	#define CPUFREQ_START (3)
	261	#define CPUFREQ_UPDATE_POLICY_CPU (4)
6dad2a29	262
74aca95d VK	263	#ifdef CONFIG_CPU_FREQ
	264	int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list);
	265	int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list);
6dad2a29	266
74aca95d VK	267	void cpufreq_notify_transition(struct cpufreq_policy *policy,
74aca95d VK	268	struct cpufreq_freqs *freqs, unsigned int state);
1da177e4	269
74aca95d VK	270	#else /* CONFIG_CPU_FREQ */
	271	static inline int cpufreq_register_notifier(struct notifier_block *nb,
	272	unsigned int list)
2eca40a8 RD	273	{
	274	return 0;
	275	}
74aca95d VK	276	static inline int cpufreq_unregister_notifier(struct notifier_block *nb,
74aca95d VK	277	unsigned int list)
95235ca2 VP	278	{
	279	return 0;
	280	}
74aca95d VK	281	#endif /* !CONFIG_CPU_FREQ */
	282
	283	/**
	284	* cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch
	285	* safe)
	286	* @old: old value
	287	* @div: divisor
	288	* @mult: multiplier
	289	*
	290	*
	291	* new = old * mult / div
	292	*/
	293	static inline unsigned long cpufreq_scale(unsigned long old, u_int div,
	294	u_int mult)
3d737108	295	{
74aca95d VK	296	#if BITS_PER_LONG == 32
	297	u64 result = ((u64) old) * ((u64) mult);
	298	do_div(result, div);
	299	return (unsigned long) result;
	300
	301	#elif BITS_PER_LONG == 64
	302	unsigned long result = old * ((u64) mult);
	303	result /= div;
	304	return result;
95235ca2	305	#endif
74aca95d	306	}
95235ca2	307
1da177e4	308	/*********************************************************************
74aca95d	309	* CPUFREQ GOVERNORS *
1da177e4 LT	310	*********************************************************************/
1da177e4 LT	311
74aca95d VK	312	/*
	313	* If (cpufreq_driver->target) exists, the ->governor decides what frequency
	314	* within the limits is used. If (cpufreq_driver->setpolicy> exists, these
	315	* two generic policies are available:
	316	*/
	317	#define CPUFREQ_POLICY_POWERSAVE (1)
	318	#define CPUFREQ_POLICY_PERFORMANCE (2)
	319
	320	/* Governor Events */
	321	#define CPUFREQ_GOV_START 1
	322	#define CPUFREQ_GOV_STOP 2
	323	#define CPUFREQ_GOV_LIMITS 3
	324	#define CPUFREQ_GOV_POLICY_INIT 4
	325	#define CPUFREQ_GOV_POLICY_EXIT 5
	326
	327	struct cpufreq_governor {
	328	char name[CPUFREQ_NAME_LEN];
	329	int initialized;
	330	int (governor) (struct cpufreq_policy policy,
	331	unsigned int event);
	332	ssize_t (show_setspeed) (struct cpufreq_policy policy,
	333	char *buf);
	334	int (store_setspeed) (struct cpufreq_policy policy,
	335	unsigned int freq);
	336	unsigned int max_transition_latency; /* HW must be able to switch to
	337	next freq faster than this value in nano secs or we
	338	will fallback to performance governor */
	339	struct list_head governor_list;
	340	struct module *owner;
	341	};
	342
	343	/* Pass a target to the cpufreq driver */
	344	int cpufreq_driver_target(struct cpufreq_policy *policy,
	345	unsigned int target_freq,
	346	unsigned int relation);
	347	int __cpufreq_driver_target(struct cpufreq_policy *policy,
	348	unsigned int target_freq,
	349	unsigned int relation);
	350	int cpufreq_register_governor(struct cpufreq_governor *governor);
	351	void cpufreq_unregister_governor(struct cpufreq_governor *governor);
	352
	353	/* CPUFREQ DEFAULT GOVERNOR */
1c256245	354	/*
bb176f7d VK	355	* Performance governor is fallback governor if any other gov failed to auto
	356	* load due latency restrictions
	357	*/
6afde10c	358	#ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE
1da177e4	359	extern struct cpufreq_governor cpufreq_gov_performance;
6afde10c	360	#endif
1c256245 TR	361	#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
1c256245 TR	362	#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_performance)
30d221db AG	363	#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE)
	364	extern struct cpufreq_governor cpufreq_gov_powersave;
	365	#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_powersave)
1da177e4 LT	366	#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE)
1da177e4 LT	367	extern struct cpufreq_governor cpufreq_gov_userspace;
1c256245 TR	368	#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_userspace)
	369	#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND)
	370	extern struct cpufreq_governor cpufreq_gov_ondemand;
	371	#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_ondemand)
	372	#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE)
	373	extern struct cpufreq_governor cpufreq_gov_conservative;
	374	#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_conservative)
1da177e4 LT	375	#endif
1da177e4 LT	376
1da177e4 LT	377	/*********************************************************************
	378	* FREQUENCY TABLE HELPERS *
	379	*********************************************************************/
	380
	381	#define CPUFREQ_ENTRY_INVALID ~0
	382	#define CPUFREQ_TABLE_END ~1
	383
	384	struct cpufreq_frequency_table {
50701588	385	unsigned int driver_data; /* driver specific data, not used by core */
1da177e4 LT	386	unsigned int frequency; /* kHz - doesn't need to be in ascending
	387	* order */
	388	};
	389
	390	int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
	391	struct cpufreq_frequency_table *table);
	392
	393	int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
	394	struct cpufreq_frequency_table *table);
	395
	396	int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
	397	struct cpufreq_frequency_table *table,
	398	unsigned int target_freq,
	399	unsigned int relation,
	400	unsigned int *index);
	401
74aca95d VK	402	void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy);
	403	ssize_t cpufreq_show_cpus(const struct cpumask mask, char buf);
	404
	405	/* the following funtion is for cpufreq core use only */
1da177e4	406	struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu);
1da177e4 LT	407
	408	/* the following are really really optional */
	409	extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs;
335dc333	410	void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
1da177e4	411	unsigned int cpu);
1da177e4	412	void cpufreq_frequency_table_put_attr(unsigned int cpu);
f4fd3797	413
1da177e4	414	#endif /* _LINUX_CPUFREQ_H */