[mirror_ubuntu-bionic-kernel.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;
	int			transition_ongoing; /* Tracks transition status */
};

/* 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;
1da177e4 LT	87	struct completion kobj_unregister;
266c13d7	88	int transition_ongoing; /* Tracks transition status */
1da177e4 LT	89	};
1da177e4 LT	90
62b36cc1	91	/* Only for ACPI */
46f18e3a VP	92	#define CPUFREQ_SHARED_TYPE_NONE (0) /* None */
	93	#define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */
	94	#define CPUFREQ_SHARED_TYPE_ALL (2) /* All dependent CPUs should set freq */
	95	#define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/
1da177e4	96
74aca95d	97	struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu);
3a3e9e06	98	void cpufreq_cpu_put(struct cpufreq_policy *policy);
74aca95d	99
2624f90c FB	100	static inline bool policy_is_shared(struct cpufreq_policy *policy)
	101	{
	102	return cpumask_weight(policy->cpus) > 1;
	103	}
	104
74aca95d VK	105	/* /sys/devices/system/cpu/cpufreq: entry point for global variables */
	106	extern struct kobject *cpufreq_global_kobject;
	107	int cpufreq_get_global_kobject(void);
	108	void cpufreq_put_global_kobject(void);
	109	int cpufreq_sysfs_create_file(const struct attribute *attr);
	110	void cpufreq_sysfs_remove_file(const struct attribute *attr);
1da177e4	111
74aca95d VK	112	#ifdef CONFIG_CPU_FREQ
	113	unsigned int cpufreq_get(unsigned int cpu);
	114	unsigned int cpufreq_quick_get(unsigned int cpu);
	115	unsigned int cpufreq_quick_get_max(unsigned int cpu);
	116	void disable_cpufreq(void);
1da177e4	117
74aca95d VK	118	u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy);
	119	int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu);
	120	int cpufreq_update_policy(unsigned int cpu);
	121	bool have_governor_per_policy(void);
	122	struct kobject get_governor_parent_kobj(struct cpufreq_policy policy);
	123	#else
	124	static inline unsigned int cpufreq_get(unsigned int cpu)
1da177e4	125	{
74aca95d VK	126	return 0;
	127	}
	128	static inline unsigned int cpufreq_quick_get(unsigned int cpu)
	129	{
	130	return 0;
	131	}
	132	static inline unsigned int cpufreq_quick_get_max(unsigned int cpu)
	133	{
	134	return 0;
	135	}
	136	static inline void disable_cpufreq(void) { }
1da177e4	137	#endif
1da177e4 LT	138
1da177e4 LT	139	/*********************************************************************
74aca95d	140	* CPUFREQ DRIVER INTERFACE *
1da177e4 LT	141	*********************************************************************/
1da177e4 LT	142
74aca95d VK	143	#define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */
74aca95d VK	144	#define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */
1da177e4	145
74aca95d VK	146	struct freq_attr {
	147	struct attribute attr;
	148	ssize_t (show)(struct cpufreq_policy , char *);
	149	ssize_t (store)(struct cpufreq_policy , const char *, size_t count);
1da177e4 LT	150	};
1da177e4 LT	151
74aca95d VK	152	#define cpufreq_freq_attr_ro(_name) \
	153	static struct freq_attr _name = \
	154	__ATTR(_name, 0444, show_##_name, NULL)
1da177e4	155
74aca95d VK	156	#define cpufreq_freq_attr_ro_perm(_name, _perm) \
	157	static struct freq_attr _name = \
	158	__ATTR(_name, _perm, show_##_name, NULL)
1da177e4	159
74aca95d VK	160	#define cpufreq_freq_attr_rw(_name) \
	161	static struct freq_attr _name = \
	162	__ATTR(_name, 0644, show_##_name, store_##_name)
	163
	164	struct global_attr {
	165	struct attribute attr;
	166	ssize_t (show)(struct kobject kobj,
	167	struct attribute attr, char buf);
	168	ssize_t (store)(struct kobject a, struct attribute *b,
	169	const char *c, size_t count);
	170	};
	171
	172	#define define_one_global_ro(_name) \
	173	static struct global_attr _name = \
	174	__ATTR(_name, 0444, show_##_name, NULL)
	175
	176	#define define_one_global_rw(_name) \
	177	static struct global_attr _name = \
	178	__ATTR(_name, 0644, show_##_name, store_##_name)
1da177e4	179
1da177e4 LT	180
1da177e4 LT	181	struct cpufreq_driver {
1da177e4 LT	182	char name[CPUFREQ_NAME_LEN];
1da177e4 LT	183	u8 flags;
4d5dcc42 VK	184	/*
	185	* This should be set by platforms having multiple clock-domains, i.e.
	186	* supporting multiple policies. With this sysfs directories of governor
	187	* would be created in cpu/cpu<num>/cpufreq/ directory and so they can
	188	* use the same governor with different tunables for different clusters.
	189	*/
	190	bool have_governor_per_policy;
1da177e4 LT	191
	192	/* needed by all drivers */
	193	int (init) (struct cpufreq_policy policy);
	194	int (verify) (struct cpufreq_policy policy);
	195
	196	/* define one out of two */
	197	int (setpolicy) (struct cpufreq_policy policy);
	198	int (target) (struct cpufreq_policy policy,
	199	unsigned int target_freq,
	200	unsigned int relation);
	201
	202	/* should be defined, if possible */
	203	unsigned int (*get) (unsigned int cpu);
	204
	205	/* optional */
e2f74f35	206	int (bios_limit) (int cpu, unsigned int limit);
bf0b90e3	207
1da177e4	208	int (exit) (struct cpufreq_policy policy);
7ca64e2d	209	int (suspend) (struct cpufreq_policy policy);
1da177e4 LT	210	int (resume) (struct cpufreq_policy policy);
	211	struct freq_attr **attr;
	212	};
	213
	214	/* flags */
335dc333	215	#define CPUFREQ_STICKY 0x01 /* the driver isn't removed even if
1da177e4	216	* all ->init() calls failed */
335dc333	217	#define CPUFREQ_CONST_LOOPS 0x02 /* loops_per_jiffy or other kernel
1da177e4 LT	218	* "constants" aren't affected by
1da177e4 LT	219	* frequency transitions */
42d4dc3f BH	220	#define CPUFREQ_PM_NO_WARN 0x04 /* don't warn on suspend/resume speed
42d4dc3f BH	221	* mismatches */
1da177e4	222
221dee28 LT	223	int cpufreq_register_driver(struct cpufreq_driver *driver_data);
221dee28 LT	224	int cpufreq_unregister_driver(struct cpufreq_driver *driver_data);
1da177e4	225
74aca95d	226	const char *cpufreq_get_current_driver(void);
1da177e4	227
bb176f7d VK	228	static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy,
bb176f7d VK	229	unsigned int min, unsigned int max)
1da177e4 LT	230	{
	231	if (policy->min < min)
	232	policy->min = min;
	233	if (policy->max < min)
	234	policy->max = min;
	235	if (policy->min > max)
	236	policy->min = max;
	237	if (policy->max > max)
	238	policy->max = max;
	239	if (policy->min > policy->max)
	240	policy->min = policy->max;
	241	return;
	242	}
	243
74aca95d VK	244	/*********************************************************************
	245	* CPUFREQ NOTIFIER INTERFACE *
	246	*********************************************************************/
6dad2a29	247
74aca95d VK	248	#define CPUFREQ_TRANSITION_NOTIFIER (0)
74aca95d VK	249	#define CPUFREQ_POLICY_NOTIFIER (1)
1da177e4	250
74aca95d VK	251	/* Transition notifiers */
	252	#define CPUFREQ_PRECHANGE (0)
	253	#define CPUFREQ_POSTCHANGE (1)
	254	#define CPUFREQ_RESUMECHANGE (8)
	255	#define CPUFREQ_SUSPENDCHANGE (9)
6dad2a29	256
74aca95d VK	257	/* Policy Notifiers */
	258	#define CPUFREQ_ADJUST (0)
	259	#define CPUFREQ_INCOMPATIBLE (1)
	260	#define CPUFREQ_NOTIFY (2)
	261	#define CPUFREQ_START (3)
	262	#define CPUFREQ_UPDATE_POLICY_CPU (4)
6dad2a29	263
74aca95d VK	264	#ifdef CONFIG_CPU_FREQ
	265	int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list);
	266	int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list);
6dad2a29	267
74aca95d VK	268	void cpufreq_notify_transition(struct cpufreq_policy *policy,
74aca95d VK	269	struct cpufreq_freqs *freqs, unsigned int state);
1da177e4	270
74aca95d VK	271	#else /* CONFIG_CPU_FREQ */
	272	static inline int cpufreq_register_notifier(struct notifier_block *nb,
	273	unsigned int list)
2eca40a8 RD	274	{
	275	return 0;
	276	}
74aca95d VK	277	static inline int cpufreq_unregister_notifier(struct notifier_block *nb,
74aca95d VK	278	unsigned int list)
95235ca2 VP	279	{
	280	return 0;
	281	}
74aca95d VK	282	#endif /* !CONFIG_CPU_FREQ */
	283
	284	/**
	285	* cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch
	286	* safe)
	287	* @old: old value
	288	* @div: divisor
	289	* @mult: multiplier
	290	*
	291	*
	292	* new = old * mult / div
	293	*/
	294	static inline unsigned long cpufreq_scale(unsigned long old, u_int div,
	295	u_int mult)
3d737108	296	{
74aca95d VK	297	#if BITS_PER_LONG == 32
	298	u64 result = ((u64) old) * ((u64) mult);
	299	do_div(result, div);
	300	return (unsigned long) result;
	301
	302	#elif BITS_PER_LONG == 64
	303	unsigned long result = old * ((u64) mult);
	304	result /= div;
	305	return result;
95235ca2	306	#endif
74aca95d	307	}
95235ca2	308
1da177e4	309	/*********************************************************************
74aca95d	310	* CPUFREQ GOVERNORS *
1da177e4 LT	311	*********************************************************************/
1da177e4 LT	312
74aca95d VK	313	/*
	314	* If (cpufreq_driver->target) exists, the ->governor decides what frequency
	315	* within the limits is used. If (cpufreq_driver->setpolicy> exists, these
	316	* two generic policies are available:
	317	*/
	318	#define CPUFREQ_POLICY_POWERSAVE (1)
	319	#define CPUFREQ_POLICY_PERFORMANCE (2)
	320
	321	/* Governor Events */
	322	#define CPUFREQ_GOV_START 1
	323	#define CPUFREQ_GOV_STOP 2
	324	#define CPUFREQ_GOV_LIMITS 3
	325	#define CPUFREQ_GOV_POLICY_INIT 4
	326	#define CPUFREQ_GOV_POLICY_EXIT 5
	327
	328	struct cpufreq_governor {
	329	char name[CPUFREQ_NAME_LEN];
	330	int initialized;
	331	int (governor) (struct cpufreq_policy policy,
	332	unsigned int event);
	333	ssize_t (show_setspeed) (struct cpufreq_policy policy,
	334	char *buf);
	335	int (store_setspeed) (struct cpufreq_policy policy,
	336	unsigned int freq);
	337	unsigned int max_transition_latency; /* HW must be able to switch to
	338	next freq faster than this value in nano secs or we
	339	will fallback to performance governor */
	340	struct list_head governor_list;
	341	struct module *owner;
	342	};
	343
	344	/* Pass a target to the cpufreq driver */
	345	int cpufreq_driver_target(struct cpufreq_policy *policy,
	346	unsigned int target_freq,
	347	unsigned int relation);
	348	int __cpufreq_driver_target(struct cpufreq_policy *policy,
	349	unsigned int target_freq,
	350	unsigned int relation);
	351	int cpufreq_register_governor(struct cpufreq_governor *governor);
	352	void cpufreq_unregister_governor(struct cpufreq_governor *governor);
	353
	354	/* CPUFREQ DEFAULT GOVERNOR */
1c256245	355	/*
bb176f7d VK	356	* Performance governor is fallback governor if any other gov failed to auto
	357	* load due latency restrictions
	358	*/
6afde10c	359	#ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE
1da177e4	360	extern struct cpufreq_governor cpufreq_gov_performance;
6afde10c	361	#endif
1c256245 TR	362	#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
1c256245 TR	363	#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_performance)
30d221db AG	364	#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE)
	365	extern struct cpufreq_governor cpufreq_gov_powersave;
	366	#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_powersave)
1da177e4 LT	367	#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE)
1da177e4 LT	368	extern struct cpufreq_governor cpufreq_gov_userspace;
1c256245 TR	369	#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_userspace)
	370	#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND)
	371	extern struct cpufreq_governor cpufreq_gov_ondemand;
	372	#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_ondemand)
	373	#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE)
	374	extern struct cpufreq_governor cpufreq_gov_conservative;
	375	#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_conservative)
1da177e4 LT	376	#endif
1da177e4 LT	377
1da177e4 LT	378	/*********************************************************************
	379	* FREQUENCY TABLE HELPERS *
	380	*********************************************************************/
	381
	382	#define CPUFREQ_ENTRY_INVALID ~0
	383	#define CPUFREQ_TABLE_END ~1
	384
	385	struct cpufreq_frequency_table {
50701588	386	unsigned int driver_data; /* driver specific data, not used by core */
1da177e4 LT	387	unsigned int frequency; /* kHz - doesn't need to be in ascending
	388	* order */
	389	};
	390
	391	int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
	392	struct cpufreq_frequency_table *table);
	393
	394	int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
	395	struct cpufreq_frequency_table *table);
	396
	397	int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
	398	struct cpufreq_frequency_table *table,
	399	unsigned int target_freq,
	400	unsigned int relation,
	401	unsigned int *index);
	402
74aca95d VK	403	void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy);
	404	ssize_t cpufreq_show_cpus(const struct cpumask mask, char buf);
	405
	406	/* the following funtion is for cpufreq core use only */
1da177e4	407	struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu);
1da177e4 LT	408
	409	/* the following are really really optional */
	410	extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs;
335dc333	411	void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
1da177e4	412	unsigned int cpu);
1da177e4	413	void cpufreq_frequency_table_put_attr(unsigned int cpu);
f4fd3797	414
1da177e4	415	#endif /* _LINUX_CPUFREQ_H */