aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/cpufreq/cpufreq_governor.h
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/cpufreq/cpufreq_governor.h')
-rw-r--r--drivers/cpufreq/cpufreq_governor.h176
1 files changed, 176 insertions, 0 deletions
diff --git a/drivers/cpufreq/cpufreq_governor.h b/drivers/cpufreq/cpufreq_governor.h
new file mode 100644
index 000000000000..f6616540c53d
--- /dev/null
+++ b/drivers/cpufreq/cpufreq_governor.h
@@ -0,0 +1,176 @@
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
17#ifndef _CPUFREQ_GOVERNER_H
18#define _CPUFREQ_GOVERNER_H
19
20#include <linux/cpufreq.h>
21#include <linux/kobject.h>
22#include <linux/mutex.h>
23#include <linux/workqueue.h>
24#include <linux/sysfs.h>
25
26/*
27 * The polling frequency depends on the capability of the processor. Default
28 * polling frequency is 1000 times the transition latency of the processor. The
29 * governor will work on any processor with transition latency <= 10mS, using
30 * appropriate sampling rate.
31 *
32 * For CPUs with transition latency > 10mS (mostly drivers with CPUFREQ_ETERNAL)
33 * this governor will not work. All times here are in uS.
34 */
35#define MIN_SAMPLING_RATE_RATIO (2)
36#define LATENCY_MULTIPLIER (1000)
37#define MIN_LATENCY_MULTIPLIER (100)
38#define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000)
39
40/* Ondemand Sampling types */
41enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE};
42
43/* Macro creating sysfs show routines */
44#define show_one(_gov, file_name, object) \
45static ssize_t show_##file_name \
46(struct kobject *kobj, struct attribute *attr, char *buf) \
47{ \
48 return sprintf(buf, "%u\n", _gov##_tuners.object); \
49}
50
51#define define_get_cpu_dbs_routines(_dbs_info) \
52static struct cpu_dbs_common_info *get_cpu_cdbs(int cpu) \
53{ \
54 return &per_cpu(_dbs_info, cpu).cdbs; \
55} \
56 \
57static void *get_cpu_dbs_info_s(int cpu) \
58{ \
59 return &per_cpu(_dbs_info, cpu); \
60}
61
62/*
63 * Abbreviations:
64 * dbs: used as a shortform for demand based switching It helps to keep variable
65 * names smaller, simpler
66 * cdbs: common dbs
67 * on_*: On-demand governor
68 * cs_*: Conservative governor
69 */
70
71/* Per cpu structures */
72struct cpu_dbs_common_info {
73 int cpu;
74 u64 prev_cpu_idle;
75 u64 prev_cpu_wall;
76 u64 prev_cpu_nice;
77 struct cpufreq_policy *cur_policy;
78 struct delayed_work work;
79 /*
80 * percpu mutex that serializes governor limit change with gov_dbs_timer
81 * invocation. We do not want gov_dbs_timer to run when user is changing
82 * the governor or limits.
83 */
84 struct mutex timer_mutex;
85};
86
87struct od_cpu_dbs_info_s {
88 struct cpu_dbs_common_info cdbs;
89 u64 prev_cpu_iowait;
90 struct cpufreq_frequency_table *freq_table;
91 unsigned int freq_lo;
92 unsigned int freq_lo_jiffies;
93 unsigned int freq_hi_jiffies;
94 unsigned int rate_mult;
95 unsigned int sample_type:1;
96};
97
98struct cs_cpu_dbs_info_s {
99 struct cpu_dbs_common_info cdbs;
100 unsigned int down_skip;
101 unsigned int requested_freq;
102 unsigned int enable:1;
103};
104
105/* Governers sysfs tunables */
106struct od_dbs_tuners {
107 unsigned int ignore_nice;
108 unsigned int sampling_rate;
109 unsigned int sampling_down_factor;
110 unsigned int up_threshold;
111 unsigned int down_differential;
112 unsigned int powersave_bias;
113 unsigned int io_is_busy;
114};
115
116struct cs_dbs_tuners {
117 unsigned int ignore_nice;
118 unsigned int sampling_rate;
119 unsigned int sampling_down_factor;
120 unsigned int up_threshold;
121 unsigned int down_threshold;
122 unsigned int freq_step;
123};
124
125/* Per Governer data */
126struct dbs_data {
127 /* Common across governors */
128 #define GOV_ONDEMAND 0
129 #define GOV_CONSERVATIVE 1
130 int governor;
131 unsigned int min_sampling_rate;
132 unsigned int enable; /* number of CPUs using this policy */
133 struct attribute_group *attr_group;
134 void *tuners;
135
136 /* dbs_mutex protects dbs_enable in governor start/stop */
137 struct mutex mutex;
138
139 struct cpu_dbs_common_info *(*get_cpu_cdbs)(int cpu);
140 void *(*get_cpu_dbs_info_s)(int cpu);
141 void (*gov_dbs_timer)(struct work_struct *work);
142 void (*gov_check_cpu)(int cpu, unsigned int load);
143
144 /* Governor specific ops, see below */
145 void *gov_ops;
146};
147
148/* Governor specific ops, will be passed to dbs_data->gov_ops */
149struct od_ops {
150 int (*io_busy)(void);
151 void (*powersave_bias_init_cpu)(int cpu);
152 unsigned int (*powersave_bias_target)(struct cpufreq_policy *policy,
153 unsigned int freq_next, unsigned int relation);
154 void (*freq_increase)(struct cpufreq_policy *p, unsigned int freq);
155};
156
157struct cs_ops {
158 struct notifier_block *notifier_block;
159};
160
161static inline int delay_for_sampling_rate(unsigned int sampling_rate)
162{
163 int delay = usecs_to_jiffies(sampling_rate);
164
165 /* We want all CPUs to do sampling nearly on same jiffy */
166 if (num_online_cpus() > 1)
167 delay -= jiffies % delay;
168
169 return delay;
170}
171
172u64 get_cpu_idle_time(unsigned int cpu, u64 *wall);
173void dbs_check_cpu(struct dbs_data *dbs_data, int cpu);
174int cpufreq_governor_dbs(struct dbs_data *dbs_data,
175 struct cpufreq_policy *policy, unsigned int event);
176#endif /* _CPUFREQ_GOVERNER_H */
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-26 13:05:17 -0500