2 * drivers/cpufreq/cpufreq_governor.h
4 * Header file for CPUFreq governors common code
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>
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.
17 #ifndef _CPUFREQ_GOVERNOR_H
18 #define _CPUFREQ_GOVERNOR_H
20 #include <linux/atomic.h>
21 #include <linux/irq_work.h>
22 #include <linux/cpufreq.h>
23 #include <linux/sched/cpufreq.h>
24 #include <linux/kernel_stat.h>
25 #include <linux/module.h>
26 #include <linux/mutex.h>
28 /* Ondemand Sampling types */
29 enum {OD_NORMAL_SAMPLE
, OD_SUB_SAMPLE
};
33 * dbs: used as a shortform for demand based switching It helps to keep variable
34 * names smaller, simpler
36 * od_*: On-demand governor
37 * cs_*: Conservative governor
40 /* Governor demand based switching data (per-policy or global). */
42 struct gov_attr_set attr_set
;
44 unsigned int min_sampling_rate
;
45 unsigned int ignore_nice_load
;
46 unsigned int sampling_rate
;
47 unsigned int sampling_down_factor
;
48 unsigned int up_threshold
;
49 unsigned int io_is_busy
;
52 static inline struct dbs_data
*to_dbs_data(struct gov_attr_set
*attr_set
)
54 return container_of(attr_set
, struct dbs_data
, attr_set
);
57 #define gov_show_one(_gov, file_name) \
58 static ssize_t show_##file_name \
59 (struct gov_attr_set *attr_set, char *buf) \
61 struct dbs_data *dbs_data = to_dbs_data(attr_set); \
62 struct _gov##_dbs_tuners *tuners = dbs_data->tuners; \
63 return sprintf(buf, "%u\n", tuners->file_name); \
66 #define gov_show_one_common(file_name) \
67 static ssize_t show_##file_name \
68 (struct gov_attr_set *attr_set, char *buf) \
70 struct dbs_data *dbs_data = to_dbs_data(attr_set); \
71 return sprintf(buf, "%u\n", dbs_data->file_name); \
74 #define gov_attr_ro(_name) \
75 static struct governor_attr _name = \
76 __ATTR(_name, 0444, show_##_name, NULL)
78 #define gov_attr_rw(_name) \
79 static struct governor_attr _name = \
80 __ATTR(_name, 0644, show_##_name, store_##_name)
82 /* Common to all CPUs of a policy */
83 struct policy_dbs_info
{
84 struct cpufreq_policy
*policy
;
86 * Per policy mutex that serializes load evaluation from limit-change
89 struct mutex update_mutex
;
94 struct irq_work irq_work
;
95 struct work_struct work
;
96 /* dbs_data may be shared between multiple policy objects */
97 struct dbs_data
*dbs_data
;
98 struct list_head list
;
99 /* Multiplier for increasing sample delay temporarily. */
100 unsigned int rate_mult
;
101 unsigned int idle_periods
; /* For conservative */
102 /* Status indicators */
103 bool is_shared
; /* This object is used by multiple CPUs */
104 bool work_in_progress
; /* Work is being queued up or in progress */
107 static inline void gov_update_sample_delay(struct policy_dbs_info
*policy_dbs
,
108 unsigned int delay_us
)
110 policy_dbs
->sample_delay_ns
= delay_us
* NSEC_PER_USEC
;
113 /* Per cpu structures */
114 struct cpu_dbs_info
{
116 u64 prev_update_time
;
119 * Used to keep track of load in the previous interval. However, when
120 * explicitly set to zero, it is used as a flag to ensure that we copy
121 * the previous load to the current interval only once, upon the first
124 unsigned int prev_load
;
125 struct update_util_data update_util
;
126 struct policy_dbs_info
*policy_dbs
;
129 /* Common Governor data across policies */
130 struct dbs_governor
{
131 struct cpufreq_governor gov
;
132 struct kobj_type kobj_type
;
135 * Common data for platforms that don't set
136 * CPUFREQ_HAVE_GOVERNOR_PER_POLICY
138 struct dbs_data
*gdbs_data
;
140 unsigned int (*gov_dbs_update
)(struct cpufreq_policy
*policy
);
141 struct policy_dbs_info
*(*alloc
)(void);
142 void (*free
)(struct policy_dbs_info
*policy_dbs
);
143 int (*init
)(struct dbs_data
*dbs_data
);
144 void (*exit
)(struct dbs_data
*dbs_data
);
145 void (*start
)(struct cpufreq_policy
*policy
);
148 static inline struct dbs_governor
*dbs_governor_of(struct cpufreq_policy
*policy
)
150 return container_of(policy
->governor
, struct dbs_governor
, gov
);
153 /* Governor callback routines */
154 int cpufreq_dbs_governor_init(struct cpufreq_policy
*policy
);
155 void cpufreq_dbs_governor_exit(struct cpufreq_policy
*policy
);
156 int cpufreq_dbs_governor_start(struct cpufreq_policy
*policy
);
157 void cpufreq_dbs_governor_stop(struct cpufreq_policy
*policy
);
158 void cpufreq_dbs_governor_limits(struct cpufreq_policy
*policy
);
160 #define CPUFREQ_DBS_GOVERNOR_INITIALIZER(_name_) \
163 .max_transition_latency = TRANSITION_LATENCY_LIMIT, \
164 .owner = THIS_MODULE, \
165 .init = cpufreq_dbs_governor_init, \
166 .exit = cpufreq_dbs_governor_exit, \
167 .start = cpufreq_dbs_governor_start, \
168 .stop = cpufreq_dbs_governor_stop, \
169 .limits = cpufreq_dbs_governor_limits, \
172 /* Governor specific operations */
174 unsigned int (*powersave_bias_target
)(struct cpufreq_policy
*policy
,
175 unsigned int freq_next
, unsigned int relation
);
178 unsigned int dbs_update(struct cpufreq_policy
*policy
);
179 void od_register_powersave_bias_handler(unsigned int (*f
)
180 (struct cpufreq_policy
*, unsigned int, unsigned int),
181 unsigned int powersave_bias
);
182 void od_unregister_powersave_bias_handler(void);
183 ssize_t
store_sampling_rate(struct gov_attr_set
*attr_set
, const char *buf
,
185 void gov_update_cpu_data(struct dbs_data
*dbs_data
);
186 #endif /* _CPUFREQ_GOVERNOR_H */