cpufreq_governor.h revision dfa5bb622555d9da0df21b50f46ebdeef390041b
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_GOVERNOR_H 18#define _CPUFREQ_GOVERNOR_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 (20) 38#define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000) 39 40/* Ondemand Sampling types */ 41enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE}; 42 43/* 44 * Macro for creating governors sysfs routines 45 * 46 * - gov_sys: One governor instance per whole system 47 * - gov_pol: One governor instance per policy 48 */ 49 50/* Create attributes */ 51#define gov_sys_attr_ro(_name) \ 52static struct global_attr _name##_gov_sys = \ 53__ATTR(_name, 0444, show_##_name##_gov_sys, NULL) 54 55#define gov_sys_attr_rw(_name) \ 56static struct global_attr _name##_gov_sys = \ 57__ATTR(_name, 0644, show_##_name##_gov_sys, store_##_name##_gov_sys) 58 59#define gov_pol_attr_ro(_name) \ 60static struct freq_attr _name##_gov_pol = \ 61__ATTR(_name, 0444, show_##_name##_gov_pol, NULL) 62 63#define gov_pol_attr_rw(_name) \ 64static struct freq_attr _name##_gov_pol = \ 65__ATTR(_name, 0644, show_##_name##_gov_pol, store_##_name##_gov_pol) 66 67#define gov_sys_pol_attr_rw(_name) \ 68 gov_sys_attr_rw(_name); \ 69 gov_pol_attr_rw(_name) 70 71#define gov_sys_pol_attr_ro(_name) \ 72 gov_sys_attr_ro(_name); \ 73 gov_pol_attr_ro(_name) 74 75/* Create show/store routines */ 76#define show_one(_gov, file_name) \ 77static ssize_t show_##file_name##_gov_sys \ 78(struct kobject *kobj, struct attribute *attr, char *buf) \ 79{ \ 80 struct _gov##_dbs_tuners *tuners = _gov##_dbs_cdata.gdbs_data->tuners; \ 81 return sprintf(buf, "%u\n", tuners->file_name); \ 82} \ 83 \ 84static ssize_t show_##file_name##_gov_pol \ 85(struct cpufreq_policy *policy, char *buf) \ 86{ \ 87 struct dbs_data *dbs_data = policy->governor_data; \ 88 struct _gov##_dbs_tuners *tuners = dbs_data->tuners; \ 89 return sprintf(buf, "%u\n", tuners->file_name); \ 90} 91 92#define store_one(_gov, file_name) \ 93static ssize_t store_##file_name##_gov_sys \ 94(struct kobject *kobj, struct attribute *attr, const char *buf, size_t count) \ 95{ \ 96 struct dbs_data *dbs_data = _gov##_dbs_cdata.gdbs_data; \ 97 return store_##file_name(dbs_data, buf, count); \ 98} \ 99 \ 100static ssize_t store_##file_name##_gov_pol \ 101(struct cpufreq_policy *policy, const char *buf, size_t count) \ 102{ \ 103 struct dbs_data *dbs_data = policy->governor_data; \ 104 return store_##file_name(dbs_data, buf, count); \ 105} 106 107#define show_store_one(_gov, file_name) \ 108show_one(_gov, file_name); \ 109store_one(_gov, file_name) 110 111/* create helper routines */ 112#define define_get_cpu_dbs_routines(_dbs_info) \ 113static struct cpu_dbs_common_info *get_cpu_cdbs(int cpu) \ 114{ \ 115 return &per_cpu(_dbs_info, cpu).cdbs; \ 116} \ 117 \ 118static void *get_cpu_dbs_info_s(int cpu) \ 119{ \ 120 return &per_cpu(_dbs_info, cpu); \ 121} 122 123/* 124 * Abbreviations: 125 * dbs: used as a shortform for demand based switching It helps to keep variable 126 * names smaller, simpler 127 * cdbs: common dbs 128 * od_*: On-demand governor 129 * cs_*: Conservative governor 130 */ 131 132/* Per cpu structures */ 133struct cpu_dbs_common_info { 134 int cpu; 135 u64 prev_cpu_idle; 136 u64 prev_cpu_wall; 137 u64 prev_cpu_nice; 138 struct cpufreq_policy *cur_policy; 139 struct delayed_work work; 140 /* 141 * percpu mutex that serializes governor limit change with gov_dbs_timer 142 * invocation. We do not want gov_dbs_timer to run when user is changing 143 * the governor or limits. 144 */ 145 struct mutex timer_mutex; 146 ktime_t time_stamp; 147}; 148 149struct od_cpu_dbs_info_s { 150 struct cpu_dbs_common_info cdbs; 151 struct cpufreq_frequency_table *freq_table; 152 unsigned int freq_lo; 153 unsigned int freq_lo_jiffies; 154 unsigned int freq_hi_jiffies; 155 unsigned int rate_mult; 156 unsigned int sample_type:1; 157}; 158 159struct cs_cpu_dbs_info_s { 160 struct cpu_dbs_common_info cdbs; 161 unsigned int down_skip; 162 unsigned int requested_freq; 163 unsigned int enable:1; 164}; 165 166/* Per policy Governers sysfs tunables */ 167struct od_dbs_tuners { 168 unsigned int ignore_nice; 169 unsigned int sampling_rate; 170 unsigned int sampling_down_factor; 171 unsigned int up_threshold; 172 unsigned int powersave_bias; 173 unsigned int io_is_busy; 174}; 175 176struct cs_dbs_tuners { 177 unsigned int ignore_nice; 178 unsigned int sampling_rate; 179 unsigned int sampling_down_factor; 180 unsigned int up_threshold; 181 unsigned int down_threshold; 182 unsigned int freq_step; 183}; 184 185/* Common Governer data across policies */ 186struct dbs_data; 187struct common_dbs_data { 188 /* Common across governors */ 189 #define GOV_ONDEMAND 0 190 #define GOV_CONSERVATIVE 1 191 int governor; 192 struct attribute_group *attr_group_gov_sys; /* one governor - system */ 193 struct attribute_group *attr_group_gov_pol; /* one governor - policy */ 194 195 /* Common data for platforms that don't set have_governor_per_policy */ 196 struct dbs_data *gdbs_data; 197 198 struct cpu_dbs_common_info *(*get_cpu_cdbs)(int cpu); 199 void *(*get_cpu_dbs_info_s)(int cpu); 200 void (*gov_dbs_timer)(struct work_struct *work); 201 void (*gov_check_cpu)(int cpu, unsigned int load); 202 int (*init)(struct dbs_data *dbs_data); 203 void (*exit)(struct dbs_data *dbs_data); 204 205 /* Governor specific ops, see below */ 206 void *gov_ops; 207}; 208 209/* Governer Per policy data */ 210struct dbs_data { 211 struct common_dbs_data *cdata; 212 unsigned int min_sampling_rate; 213 int usage_count; 214 void *tuners; 215 216 /* dbs_mutex protects dbs_enable in governor start/stop */ 217 struct mutex mutex; 218}; 219 220/* Governor specific ops, will be passed to dbs_data->gov_ops */ 221struct od_ops { 222 void (*powersave_bias_init_cpu)(int cpu); 223 unsigned int (*powersave_bias_target)(struct cpufreq_policy *policy, 224 unsigned int freq_next, unsigned int relation); 225 void (*freq_increase)(struct cpufreq_policy *p, unsigned int freq); 226}; 227 228struct cs_ops { 229 struct notifier_block *notifier_block; 230}; 231 232static inline int delay_for_sampling_rate(unsigned int sampling_rate) 233{ 234 int delay = usecs_to_jiffies(sampling_rate); 235 236 /* We want all CPUs to do sampling nearly on same jiffy */ 237 if (num_online_cpus() > 1) 238 delay -= jiffies % delay; 239 240 return delay; 241} 242 243#define declare_show_sampling_rate_min(_gov) \ 244static ssize_t show_sampling_rate_min_gov_sys \ 245(struct kobject *kobj, struct attribute *attr, char *buf) \ 246{ \ 247 struct dbs_data *dbs_data = _gov##_dbs_cdata.gdbs_data; \ 248 return sprintf(buf, "%u\n", dbs_data->min_sampling_rate); \ 249} \ 250 \ 251static ssize_t show_sampling_rate_min_gov_pol \ 252(struct cpufreq_policy *policy, char *buf) \ 253{ \ 254 struct dbs_data *dbs_data = policy->governor_data; \ 255 return sprintf(buf, "%u\n", dbs_data->min_sampling_rate); \ 256} 257 258void dbs_check_cpu(struct dbs_data *dbs_data, int cpu); 259bool need_load_eval(struct cpu_dbs_common_info *cdbs, 260 unsigned int sampling_rate); 261int cpufreq_governor_dbs(struct cpufreq_policy *policy, 262 struct common_dbs_data *cdata, unsigned int event); 263void gov_queue_work(struct dbs_data *dbs_data, struct cpufreq_policy *policy, 264 unsigned int delay, bool all_cpus); 265void od_register_powersave_bias_handler(unsigned int (*f) 266 (struct cpufreq_policy *, unsigned int, unsigned int), 267 unsigned int powersave_bias); 268void od_unregister_powersave_bias_handler(void); 269#endif /* _CPUFREQ_GOVERNOR_H */ 270