[mirror_ubuntu-zesty-kernel.git] / drivers / cpufreq / cpufreq_governor.h

/*
 * drivers/cpufreq/cpufreq_governor.h
 *
 * Header file for CPUFreq governors common code
 *
 * Copyright	(C) 2001 Russell King
 *		(C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
 *		(C) 2003 Jun Nakajima <jun.nakajima@intel.com>
 *		(C) 2009 Alexander Clouter <alex@digriz.org.uk>
 *		(c) 2012 Viresh Kumar <viresh.kumar@linaro.org>
 *
 * 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 _CPUFREQ_GOVERNOR_H
#define _CPUFREQ_GOVERNOR_H

#include <linux/atomic.h>
#include <linux/irq_work.h>
#include <linux/cpufreq.h>
#include <linux/kernel_stat.h>
#include <linux/module.h>
#include <linux/mutex.h>

/* Ondemand Sampling types */
enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE};

/*
 * Abbreviations:
 * dbs: used as a shortform for demand based switching It helps to keep variable
 *	names smaller, simpler
 * cdbs: common dbs
 * od_*: On-demand governor
 * cs_*: Conservative governor
 */

/* Governor demand based switching data (per-policy or global). */
struct dbs_data {
	struct gov_attr_set attr_set;
	void *tuners;
	unsigned int min_sampling_rate;
	unsigned int ignore_nice_load;
	unsigned int sampling_rate;
	unsigned int sampling_down_factor;
	unsigned int up_threshold;
	unsigned int io_is_busy;
};

static inline struct dbs_data *to_dbs_data(struct gov_attr_set *attr_set)
{
	return container_of(attr_set, struct dbs_data, attr_set);
}

#define gov_show_one(_gov, file_name)					\
static ssize_t show_##file_name						\
(struct gov_attr_set *attr_set, char *buf)				\
{									\
	struct dbs_data *dbs_data = to_dbs_data(attr_set);		\
	struct _gov##_dbs_tuners *tuners = dbs_data->tuners;		\
	return sprintf(buf, "%u\n", tuners->file_name);			\
}

#define gov_show_one_common(file_name)					\
static ssize_t show_##file_name						\
(struct gov_attr_set *attr_set, char *buf)				\
{									\
	struct dbs_data *dbs_data = to_dbs_data(attr_set);		\
	return sprintf(buf, "%u\n", dbs_data->file_name);		\
}

#define gov_attr_ro(_name)						\
static struct governor_attr _name =					\
__ATTR(_name, 0444, show_##_name, NULL)

#define gov_attr_rw(_name)						\
static struct governor_attr _name =					\
__ATTR(_name, 0644, show_##_name, store_##_name)

/* Common to all CPUs of a policy */
struct policy_dbs_info {
	struct cpufreq_policy *policy;
	/*
	 * Per policy mutex that serializes load evaluation from limit-change
	 * and work-handler.
	 */
	struct mutex update_mutex;

	u64 last_sample_time;
	s64 sample_delay_ns;
	atomic_t work_count;
	struct irq_work irq_work;
	struct work_struct work;
	/* dbs_data may be shared between multiple policy objects */
	struct dbs_data *dbs_data;
	struct list_head list;
	/* Multiplier for increasing sample delay temporarily. */
	unsigned int rate_mult;
	unsigned int idle_periods;	/* For conservative */
	/* Status indicators */
	bool is_shared;		/* This object is used by multiple CPUs */
	bool work_in_progress;	/* Work is being queued up or in progress */
};

static inline void gov_update_sample_delay(struct policy_dbs_info *policy_dbs,
					   unsigned int delay_us)
{
	policy_dbs->sample_delay_ns = delay_us * NSEC_PER_USEC;
}

/* Per cpu structures */
struct cpu_dbs_info {
	u64 prev_cpu_idle;
	u64 prev_update_time;
	u64 prev_cpu_nice;
	/*
	 * Used to keep track of load in the previous interval. However, when
	 * explicitly set to zero, it is used as a flag to ensure that we copy
	 * the previous load to the current interval only once, upon the first
	 * wake-up from idle.
	 */
	unsigned int prev_load;
	struct update_util_data update_util;
	struct policy_dbs_info *policy_dbs;
};

/* Common Governor data across policies */
struct dbs_governor {
	struct cpufreq_governor gov;
	struct kobj_type kobj_type;

	/*
	 * Common data for platforms that don't set
	 * CPUFREQ_HAVE_GOVERNOR_PER_POLICY
	 */
	struct dbs_data *gdbs_data;

	unsigned int (*gov_dbs_update)(struct cpufreq_policy *policy);
	struct policy_dbs_info *(*alloc)(void);
	void (*free)(struct policy_dbs_info *policy_dbs);
	int (*init)(struct dbs_data *dbs_data);
	void (*exit)(struct dbs_data *dbs_data);
	void (*start)(struct cpufreq_policy *policy);
};

static inline struct dbs_governor *dbs_governor_of(struct cpufreq_policy *policy)
{
	return container_of(policy->governor, struct dbs_governor, gov);
}

/* Governor callback routines */
int cpufreq_dbs_governor_init(struct cpufreq_policy *policy);
void cpufreq_dbs_governor_exit(struct cpufreq_policy *policy);
int cpufreq_dbs_governor_start(struct cpufreq_policy *policy);
void cpufreq_dbs_governor_stop(struct cpufreq_policy *policy);
void cpufreq_dbs_governor_limits(struct cpufreq_policy *policy);

#define CPUFREQ_DBS_GOVERNOR_INITIALIZER(_name_)			\
	{								\
		.name = _name_,						\
		.max_transition_latency	= TRANSITION_LATENCY_LIMIT,	\
		.owner = THIS_MODULE,					\
		.init = cpufreq_dbs_governor_init,			\
		.exit = cpufreq_dbs_governor_exit,			\
		.start = cpufreq_dbs_governor_start,			\
		.stop = cpufreq_dbs_governor_stop,			\
		.limits = cpufreq_dbs_governor_limits,			\
	}

/* Governor specific operations */
struct od_ops {
	unsigned int (*powersave_bias_target)(struct cpufreq_policy *policy,
			unsigned int freq_next, unsigned int relation);
};

unsigned int dbs_update(struct cpufreq_policy *policy);
void od_register_powersave_bias_handler(unsigned int (*f)
		(struct cpufreq_policy *, unsigned int, unsigned int),
		unsigned int powersave_bias);
void od_unregister_powersave_bias_handler(void);
ssize_t store_sampling_rate(struct gov_attr_set *attr_set, const char *buf,
			    size_t count);
void gov_update_cpu_data(struct dbs_data *dbs_data);
#endif /* _CPUFREQ_GOVERNOR_H */
Commit	Line	Data
4471a34f VK	1	/*
	2	* drivers/cpufreq/cpufreq_governor.h
	3	*
	4	* Header file for CPUFreq governors common code
	5	*
	6	* Copyright (C) 2001 Russell King
	7	* (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
	8	* (C) 2003 Jun Nakajima <jun.nakajima@intel.com>
	9	* (C) 2009 Alexander Clouter <alex@digriz.org.uk>
	10	* (c) 2012 Viresh Kumar <viresh.kumar@linaro.org>
	11	*
	12	* This program is free software; you can redistribute it and/or modify
	13	* it under the terms of the GNU General Public License version 2 as
	14	* published by the Free Software Foundation.
	15	*/
	16
beb0ff39 BP	17	#ifndef _CPUFREQ_GOVERNOR_H
beb0ff39 BP	18	#define _CPUFREQ_GOVERNOR_H
4471a34f	19
2dd3e724	20	#include <linux/atomic.h>
9be4fd2c	21	#include <linux/irq_work.h>
4471a34f	22	#include <linux/cpufreq.h>
5ff0a268 VK	23	#include <linux/kernel_stat.h>
5ff0a268 VK	24	#include <linux/module.h>
4471a34f	25	#include <linux/mutex.h>
4471a34f	26
4471a34f VK	27	/* Ondemand Sampling types */
	28	enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE};
	29
4471a34f VK	30	/*
	31	* Abbreviations:
	32	* dbs: used as a shortform for demand based switching It helps to keep variable
	33	* names smaller, simpler
	34	* cdbs: common dbs
e5dde92c	35	* od_*: On-demand governor
4471a34f VK	36	* cs_*: Conservative governor
	37	*/
	38
bc505475 RW	39	/* Governor demand based switching data (per-policy or global). */
bc505475 RW	40	struct dbs_data {
0dd3c1d6	41	struct gov_attr_set attr_set;
bc505475	42	void *tuners;
ff4b1789 VK	43	unsigned int min_sampling_rate;
	44	unsigned int ignore_nice_load;
	45	unsigned int sampling_rate;
	46	unsigned int sampling_down_factor;
	47	unsigned int up_threshold;
8847e038	48	unsigned int io_is_busy;
c4435630 VK	49	};
c4435630 VK	50
0dd3c1d6 RW	51	static inline struct dbs_data to_dbs_data(struct gov_attr_set attr_set)
	52	{
	53	return container_of(attr_set, struct dbs_data, attr_set);
	54	}
	55
c4435630 VK	56	#define gov_show_one(_gov, file_name) \
c4435630 VK	57	static ssize_t show_##file_name \
0dd3c1d6	58	(struct gov_attr_set attr_set, char buf) \
c4435630	59	{ \
0dd3c1d6	60	struct dbs_data *dbs_data = to_dbs_data(attr_set); \
c4435630 VK	61	struct _gov##_dbs_tuners *tuners = dbs_data->tuners; \
	62	return sprintf(buf, "%u\n", tuners->file_name); \
	63	}
	64
	65	#define gov_show_one_common(file_name) \
	66	static ssize_t show_##file_name \
0dd3c1d6	67	(struct gov_attr_set attr_set, char buf) \
c4435630	68	{ \
0dd3c1d6	69	struct dbs_data *dbs_data = to_dbs_data(attr_set); \
c4435630 VK	70	return sprintf(buf, "%u\n", dbs_data->file_name); \
	71	}
	72
	73	#define gov_attr_ro(_name) \
	74	static struct governor_attr _name = \
	75	__ATTR(_name, 0444, show_##_name, NULL)
	76
	77	#define gov_attr_rw(_name) \
	78	static struct governor_attr _name = \
	79	__ATTR(_name, 0644, show_##_name, store_##_name)
	80
44152cb8	81	/* Common to all CPUs of a policy */
e40e7b25	82	struct policy_dbs_info {
44152cb8 VK	83	struct cpufreq_policy *policy;
44152cb8 VK	84	/*
70f43e5e VK	85	* Per policy mutex that serializes load evaluation from limit-change
70f43e5e VK	86	* and work-handler.
44152cb8	87	*/
26f0dbc9	88	struct mutex update_mutex;
70f43e5e	89
9be4fd2c RW	90	u64 last_sample_time;
9be4fd2c RW	91	s64 sample_delay_ns;
686cc637	92	atomic_t work_count;
9be4fd2c	93	struct irq_work irq_work;
70f43e5e	94	struct work_struct work;
bc505475 RW	95	/* dbs_data may be shared between multiple policy objects */
bc505475 RW	96	struct dbs_data *dbs_data;
c54df071	97	struct list_head list;
57dc3bcd RW	98	/* Multiplier for increasing sample delay temporarily. */
57dc3bcd RW	99	unsigned int rate_mult;
00bfe058	100	unsigned int idle_periods; /* For conservative */
e4db2813 RW	101	/* Status indicators */
	102	bool is_shared; /* This object is used by multiple CPUs */
	103	bool work_in_progress; /* Work is being queued up or in progress */
44152cb8 VK	104	};
44152cb8 VK	105
e40e7b25	106	static inline void gov_update_sample_delay(struct policy_dbs_info *policy_dbs,
9be4fd2c RW	107	unsigned int delay_us)
9be4fd2c RW	108	{
e40e7b25	109	policy_dbs->sample_delay_ns = delay_us * NSEC_PER_USEC;
9be4fd2c RW	110	}
9be4fd2c RW	111
4471a34f	112	/* Per cpu structures */
875b8508	113	struct cpu_dbs_info {
1e7586a1	114	u64 prev_cpu_idle;
b4f4b4b3	115	u64 prev_update_time;
1e7586a1	116	u64 prev_cpu_nice;
18b46abd	117	/*
c8ae481b VK	118	* Used to keep track of load in the previous interval. However, when
	119	* explicitly set to zero, it is used as a flag to ensure that we copy
	120	* the previous load to the current interval only once, upon the first
	121	* wake-up from idle.
18b46abd	122	*/
c8ae481b	123	unsigned int prev_load;
9be4fd2c	124	struct update_util_data update_util;
e40e7b25	125	struct policy_dbs_info *policy_dbs;
4471a34f VK	126	};
4471a34f VK	127
c4afc410	128	/* Common Governor data across policies */
7bdad34d	129	struct dbs_governor {
af926185	130	struct cpufreq_governor gov;
c4435630	131	struct kobj_type kobj_type;
4471a34f	132
0b981e70 VK	133	/*
	134	* Common data for platforms that don't set
	135	* CPUFREQ_HAVE_GOVERNOR_PER_POLICY
	136	*/
4d5dcc42	137	struct dbs_data *gdbs_data;
4471a34f	138
26f0dbc9	139	unsigned int (gov_dbs_update)(struct cpufreq_policy policy);
7d5a9956 RW	140	struct policy_dbs_info (alloc)(void);
7d5a9956 RW	141	void (free)(struct policy_dbs_info policy_dbs);
9a15fb2c RW	142	int (init)(struct dbs_data dbs_data);
9a15fb2c RW	143	void (exit)(struct dbs_data dbs_data);
702c9e54	144	void (start)(struct cpufreq_policy policy);
4471a34f VK	145	};
4471a34f VK	146
ea59ee0d RW	147	static inline struct dbs_governor dbs_governor_of(struct cpufreq_policy policy)
	148	{
	149	return container_of(policy->governor, struct dbs_governor, gov);
	150	}
	151
e788892b RW	152	/* Governor callback routines */
	153	int cpufreq_dbs_governor_init(struct cpufreq_policy *policy);
	154	void cpufreq_dbs_governor_exit(struct cpufreq_policy *policy);
	155	int cpufreq_dbs_governor_start(struct cpufreq_policy *policy);
	156	void cpufreq_dbs_governor_stop(struct cpufreq_policy *policy);
	157	void cpufreq_dbs_governor_limits(struct cpufreq_policy *policy);
	158
	159	#define CPUFREQ_DBS_GOVERNOR_INITIALIZER(_name_) \
	160	{ \
	161	.name = _name_, \
	162	.max_transition_latency = TRANSITION_LATENCY_LIMIT, \
	163	.owner = THIS_MODULE, \
	164	.init = cpufreq_dbs_governor_init, \
	165	.exit = cpufreq_dbs_governor_exit, \
	166	.start = cpufreq_dbs_governor_start, \
	167	.stop = cpufreq_dbs_governor_stop, \
	168	.limits = cpufreq_dbs_governor_limits, \
	169	}
	170
8434dadb	171	/* Governor specific operations */
4471a34f	172	struct od_ops {
4471a34f VK	173	unsigned int (powersave_bias_target)(struct cpufreq_policy policy,
4471a34f VK	174	unsigned int freq_next, unsigned int relation);
4471a34f VK	175	};
4471a34f VK	176
4cccf755	177	unsigned int dbs_update(struct cpufreq_policy *policy);
fb30809e JS	178	void od_register_powersave_bias_handler(unsigned int (*f)
	179	(struct cpufreq_policy *, unsigned int, unsigned int),
	180	unsigned int powersave_bias);
	181	void od_unregister_powersave_bias_handler(void);
0dd3c1d6	182	ssize_t store_sampling_rate(struct gov_attr_set attr_set, const char buf,
aded387b	183	size_t count);
8c8f77fd	184	void gov_update_cpu_data(struct dbs_data *dbs_data);
beb0ff39	185	#endif /* _CPUFREQ_GOVERNOR_H */