[linux-block.git] / drivers / cpufreq / cpufreq_governor.h

/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * 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>
 */

#ifndef _CPUFREQ_GOVERNOR_H
#define _CPUFREQ_GOVERNOR_H

#include <linux/atomic.h>
#include <linux/irq_work.h>
#include <linux/cpufreq.h>
#include <linux/sched/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 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 file_name##_show						\
(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 file_name##_show						\
(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_RO(_name)

#define gov_attr_rw(_name)						\
static struct governor_attr _name = __ATTR_RW(_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_,						\
		.flags = CPUFREQ_GOV_DYNAMIC_SWITCHING,			\
		.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 sampling_rate_store(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
d2912cb1	1	/* SPDX-License-Identifier: GPL-2.0-only */
4471a34f VK	2	/*
	3	* drivers/cpufreq/cpufreq_governor.h
	4	*
	5	* Header file for CPUFreq governors common code
	6	*
	7	* Copyright (C) 2001 Russell King
	8	* (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
	9	* (C) 2003 Jun Nakajima <jun.nakajima@intel.com>
	10	* (C) 2009 Alexander Clouter <alex@digriz.org.uk>
	11	* (c) 2012 Viresh Kumar <viresh.kumar@linaro.org>
4471a34f VK	12	*/
4471a34f VK	13
beb0ff39 BP	14	#ifndef _CPUFREQ_GOVERNOR_H
beb0ff39 BP	15	#define _CPUFREQ_GOVERNOR_H
4471a34f	16
2dd3e724	17	#include <linux/atomic.h>
9be4fd2c	18	#include <linux/irq_work.h>
4471a34f	19	#include <linux/cpufreq.h>
55687da1	20	#include <linux/sched/cpufreq.h>
5ff0a268 VK	21	#include <linux/kernel_stat.h>
5ff0a268 VK	22	#include <linux/module.h>
4471a34f	23	#include <linux/mutex.h>
4471a34f	24
4471a34f VK	25	/* Ondemand Sampling types */
	26	enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE};
	27
4471a34f VK	28	/*
	29	* Abbreviations:
	30	* dbs: used as a shortform for demand based switching It helps to keep variable
	31	* names smaller, simpler
	32	* cdbs: common dbs
e5dde92c	33	* od_*: On-demand governor
4471a34f VK	34	* cs_*: Conservative governor
	35	*/
	36
bc505475 RW	37	/* Governor demand based switching data (per-policy or global). */
bc505475 RW	38	struct dbs_data {
0dd3c1d6	39	struct gov_attr_set attr_set;
bc505475	40	void *tuners;
ff4b1789 VK	41	unsigned int ignore_nice_load;
	42	unsigned int sampling_rate;
	43	unsigned int sampling_down_factor;
	44	unsigned int up_threshold;
8847e038	45	unsigned int io_is_busy;
c4435630 VK	46	};
c4435630 VK	47
0dd3c1d6 RW	48	static inline struct dbs_data to_dbs_data(struct gov_attr_set attr_set)
	49	{
	50	return container_of(attr_set, struct dbs_data, attr_set);
	51	}
	52
c4435630	53	#define gov_show_one(_gov, file_name) \
85750bcd	54	static ssize_t file_name##_show \
0dd3c1d6	55	(struct gov_attr_set attr_set, char buf) \
c4435630	56	{ \
0dd3c1d6	57	struct dbs_data *dbs_data = to_dbs_data(attr_set); \
c4435630 VK	58	struct _gov##_dbs_tuners *tuners = dbs_data->tuners; \
	59	return sprintf(buf, "%u\n", tuners->file_name); \
	60	}
	61
	62	#define gov_show_one_common(file_name) \
85750bcd	63	static ssize_t file_name##_show \
0dd3c1d6	64	(struct gov_attr_set attr_set, char buf) \
c4435630	65	{ \
0dd3c1d6	66	struct dbs_data *dbs_data = to_dbs_data(attr_set); \
c4435630 VK	67	return sprintf(buf, "%u\n", dbs_data->file_name); \
	68	}
	69
	70	#define gov_attr_ro(_name) \
85750bcd	71	static struct governor_attr _name = __ATTR_RO(_name)
c4435630 VK	72
c4435630 VK	73	#define gov_attr_rw(_name) \
85750bcd	74	static struct governor_attr _name = __ATTR_RW(_name)
c4435630	75
44152cb8	76	/* Common to all CPUs of a policy */
e40e7b25	77	struct policy_dbs_info {
44152cb8 VK	78	struct cpufreq_policy *policy;
44152cb8 VK	79	/*
70f43e5e VK	80	* Per policy mutex that serializes load evaluation from limit-change
70f43e5e VK	81	* and work-handler.
44152cb8	82	*/
26f0dbc9	83	struct mutex update_mutex;
70f43e5e	84
9be4fd2c RW	85	u64 last_sample_time;
9be4fd2c RW	86	s64 sample_delay_ns;
686cc637	87	atomic_t work_count;
9be4fd2c	88	struct irq_work irq_work;
70f43e5e	89	struct work_struct work;
bc505475 RW	90	/* dbs_data may be shared between multiple policy objects */
bc505475 RW	91	struct dbs_data *dbs_data;
c54df071	92	struct list_head list;
57dc3bcd RW	93	/* Multiplier for increasing sample delay temporarily. */
57dc3bcd RW	94	unsigned int rate_mult;
00bfe058	95	unsigned int idle_periods; /* For conservative */
e4db2813 RW	96	/* Status indicators */
	97	bool is_shared; /* This object is used by multiple CPUs */
	98	bool work_in_progress; /* Work is being queued up or in progress */
44152cb8 VK	99	};
44152cb8 VK	100
e40e7b25	101	static inline void gov_update_sample_delay(struct policy_dbs_info *policy_dbs,
9be4fd2c RW	102	unsigned int delay_us)
9be4fd2c RW	103	{
e40e7b25	104	policy_dbs->sample_delay_ns = delay_us * NSEC_PER_USEC;
9be4fd2c RW	105	}
9be4fd2c RW	106
4471a34f	107	/* Per cpu structures */
875b8508	108	struct cpu_dbs_info {
1e7586a1	109	u64 prev_cpu_idle;
b4f4b4b3	110	u64 prev_update_time;
1e7586a1	111	u64 prev_cpu_nice;
18b46abd	112	/*
c8ae481b VK	113	* Used to keep track of load in the previous interval. However, when
	114	* explicitly set to zero, it is used as a flag to ensure that we copy
	115	* the previous load to the current interval only once, upon the first
	116	* wake-up from idle.
18b46abd	117	*/
c8ae481b	118	unsigned int prev_load;
9be4fd2c	119	struct update_util_data update_util;
e40e7b25	120	struct policy_dbs_info *policy_dbs;
4471a34f VK	121	};
4471a34f VK	122
c4afc410	123	/* Common Governor data across policies */
7bdad34d	124	struct dbs_governor {
af926185	125	struct cpufreq_governor gov;
c4435630	126	struct kobj_type kobj_type;
4471a34f	127
0b981e70 VK	128	/*
	129	* Common data for platforms that don't set
	130	* CPUFREQ_HAVE_GOVERNOR_PER_POLICY
	131	*/
4d5dcc42	132	struct dbs_data *gdbs_data;
4471a34f	133
26f0dbc9	134	unsigned int (gov_dbs_update)(struct cpufreq_policy policy);
7d5a9956 RW	135	struct policy_dbs_info (alloc)(void);
7d5a9956 RW	136	void (free)(struct policy_dbs_info policy_dbs);
9a15fb2c RW	137	int (init)(struct dbs_data dbs_data);
9a15fb2c RW	138	void (exit)(struct dbs_data dbs_data);
702c9e54	139	void (start)(struct cpufreq_policy policy);
4471a34f VK	140	};
4471a34f VK	141
ea59ee0d RW	142	static inline struct dbs_governor dbs_governor_of(struct cpufreq_policy policy)
	143	{
	144	return container_of(policy->governor, struct dbs_governor, gov);
	145	}
	146
e788892b RW	147	/* Governor callback routines */
	148	int cpufreq_dbs_governor_init(struct cpufreq_policy *policy);
	149	void cpufreq_dbs_governor_exit(struct cpufreq_policy *policy);
	150	int cpufreq_dbs_governor_start(struct cpufreq_policy *policy);
	151	void cpufreq_dbs_governor_stop(struct cpufreq_policy *policy);
	152	void cpufreq_dbs_governor_limits(struct cpufreq_policy *policy);
	153
	154	#define CPUFREQ_DBS_GOVERNOR_INITIALIZER(_name_) \
	155	{ \
	156	.name = _name_, \
9a2a9ebc	157	.flags = CPUFREQ_GOV_DYNAMIC_SWITCHING, \
e788892b RW	158	.owner = THIS_MODULE, \
	159	.init = cpufreq_dbs_governor_init, \
	160	.exit = cpufreq_dbs_governor_exit, \
	161	.start = cpufreq_dbs_governor_start, \
	162	.stop = cpufreq_dbs_governor_stop, \
	163	.limits = cpufreq_dbs_governor_limits, \
	164	}
	165
8434dadb	166	/* Governor specific operations */
4471a34f	167	struct od_ops {
4471a34f VK	168	unsigned int (powersave_bias_target)(struct cpufreq_policy policy,
4471a34f VK	169	unsigned int freq_next, unsigned int relation);
4471a34f VK	170	};
4471a34f VK	171
4cccf755	172	unsigned int dbs_update(struct cpufreq_policy *policy);
fb30809e JS	173	void od_register_powersave_bias_handler(unsigned int (*f)
	174	(struct cpufreq_policy *, unsigned int, unsigned int),
	175	unsigned int powersave_bias);
	176	void od_unregister_powersave_bias_handler(void);
85750bcd	177	ssize_t sampling_rate_store(struct gov_attr_set attr_set, const char buf,
aded387b	178	size_t count);
8c8f77fd	179	void gov_update_cpu_data(struct dbs_data *dbs_data);
beb0ff39	180	#endif /* _CPUFREQ_GOVERNOR_H */