drivers/cpufreq/cpufreq_governor.h

   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 */
  41 enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE};
  42
  43 /* Hotplug Sampling types */
  44 enum {HP_NORMAL_SAMPLE, HP_SUB_SAMPLE};
  45
  46 /*
  47  * Macro for creating governors sysfs routines
  48  *
  49  * - gov_sys: One governor instance per whole system
  50  * - gov_pol: One governor instance per policy
  51  */
  52
  53 /* Create attributes */
  54 #define gov_sys_attr_ro(_name)                                          \
  55 static struct global_attr _name##_gov_sys =                             \
  56 __ATTR(_name, 0444, show_##_name##_gov_sys, NULL)
  57
  58 #define gov_sys_attr_rw(_name)                                          \
  59 static struct global_attr _name##_gov_sys =                             \
  60 __ATTR(_name, 0644, show_##_name##_gov_sys, store_##_name##_gov_sys)
  61
  62 #define gov_pol_attr_ro(_name)                                          \
  63 static struct freq_attr _name##_gov_pol =                               \
  64 __ATTR(_name, 0444, show_##_name##_gov_pol, NULL)
  65
  66 #define gov_pol_attr_rw(_name)                                          \
  67 static struct freq_attr _name##_gov_pol =                               \
  68 __ATTR(_name, 0644, show_##_name##_gov_pol, store_##_name##_gov_pol)
  69
  70 #define gov_sys_pol_attr_rw(_name)                                      \
  71         gov_sys_attr_rw(_name);                                         \
  72         gov_pol_attr_rw(_name)
  73
  74 #define gov_sys_pol_attr_ro(_name)                                      \
  75         gov_sys_attr_ro(_name);                                         \
  76         gov_pol_attr_ro(_name)
  77
  78 /* Create show/store routines */
  79 #define show_one(_gov, file_name)                                       \
  80 static ssize_t show_##file_name##_gov_sys                               \
  81 (struct kobject *kobj, struct attribute *attr, char *buf)               \
  82 {                                                                       \
  83         struct _gov##_dbs_tuners *tuners = _gov##_dbs_cdata.gdbs_data->tuners; \
  84         return sprintf(buf, "%u\n", tuners->file_name);                 \
  85 }                                                                       \
  86                                                                         \
  87 static ssize_t show_##file_name##_gov_pol                                       \
  88 (struct cpufreq_policy *policy, char *buf)                              \
  89 {                                                                       \
  90         struct dbs_data *dbs_data = policy->governor_data;              \
  91         struct _gov##_dbs_tuners *tuners = dbs_data->tuners;            \
  92         return sprintf(buf, "%u\n", tuners->file_name);                 \
  93 }
  94
  95 #define store_one(_gov, file_name)                                      \
  96 static ssize_t store_##file_name##_gov_sys                              \
  97 (struct kobject *kobj, struct attribute *attr, const char *buf, size_t count)   \
  98 {                                                                       \
  99         struct dbs_data *dbs_data = _gov##_dbs_cdata.gdbs_data;         \
 100         return store_##file_name(dbs_data, buf, count);                 \
 101 }                                                                       \
 102                                                                         \
 103 static ssize_t store_##file_name##_gov_pol                              \
 104 (struct cpufreq_policy *policy, const char *buf, size_t count)          \
 105 {                                                                       \
 106         struct dbs_data *dbs_data = policy->governor_data;              \
 107         return store_##file_name(dbs_data, buf, count);                 \
 108 }
 109
 110 #define show_store_one(_gov, file_name)                                 \
 111 show_one(_gov, file_name);                                              \
 112 store_one(_gov, file_name)
 113
 114 /* create helper routines */
 115 #define define_get_cpu_dbs_routines(_dbs_info)                          \
 116 static struct cpu_dbs_common_info *get_cpu_cdbs(int cpu)                \
 117 {                                                                       \
 118         return &per_cpu(_dbs_info, cpu).cdbs;                           \
 119 }                                                                       \
 120                                                                         \
 121 static void *get_cpu_dbs_info_s(int cpu)                                \
 122 {                                                                       \
 123         return &per_cpu(_dbs_info, cpu);                                \
 124 }
 125
 126 /*
 127  * Abbreviations:
 128  * dbs: used as a shortform for demand based switching It helps to keep variable
 129  *      names smaller, simpler
 130  * cdbs: common dbs
 131  * od_*: On-demand governor
 132  * cs_*: Conservative governor
 133  * hp_*: Hotplug governor
 134  */
 135
 136 /* Per cpu structures */
 137 struct cpu_dbs_common_info {
 138         int cpu;
 139         u64 prev_cpu_idle;
 140         u64 prev_cpu_wall;
 141         u64 prev_cpu_nice;
 142         struct cpufreq_policy *cur_policy;
 143         struct delayed_work work;
 144         /*
 145          * percpu mutex that serializes governor limit change with gov_dbs_timer
 146          * invocation. We do not want gov_dbs_timer to run when user is changing
 147          * the governor or limits.
 148          */
 149         struct mutex timer_mutex;
 150         ktime_t time_stamp;
 151 };
 152
 153 struct od_cpu_dbs_info_s {
 154         struct cpu_dbs_common_info cdbs;
 155         struct cpufreq_frequency_table *freq_table;
 156         unsigned int freq_lo;
 157         unsigned int freq_lo_jiffies;
 158         unsigned int freq_hi_jiffies;
 159         unsigned int rate_mult;
 160         unsigned int sample_type:1;
 161 };
 162
 163 struct cs_cpu_dbs_info_s {
 164         struct cpu_dbs_common_info cdbs;
 165         unsigned int down_skip;
 166         unsigned int requested_freq;
 167         unsigned int enable:1;
 168 };
 169
 170 struct hp_cpu_dbs_info_s {
 171         struct cpu_dbs_common_info cdbs;
 172         struct cpufreq_frequency_table *freq_table;
 173         unsigned int freq_lo;
 174         unsigned int freq_lo_jiffies;
 175         unsigned int freq_hi_jiffies;
 176         unsigned int rate_mult;
 177         unsigned int sample_type:1;
 178 };
 179
 180 /* Per policy Governers sysfs tunables */
 181 struct od_dbs_tuners {
 182         unsigned int ignore_nice_load;
 183         unsigned int sampling_rate;
 184         unsigned int sampling_down_factor;
 185         unsigned int up_threshold;
 186         unsigned int powersave_bias;
 187         unsigned int io_is_busy;
 188 };
 189
 190 struct cs_dbs_tuners {
 191         unsigned int ignore_nice_load;
 192         unsigned int sampling_rate;
 193         unsigned int sampling_down_factor;
 194         unsigned int up_threshold;
 195         unsigned int down_threshold;
 196         unsigned int freq_step;
 197 };
 198
 199 struct hp_dbs_tuners {
 200         unsigned int ignore_nice_load;
 201         unsigned int sampling_rate;
 202         unsigned int sampling_down_factor;
 203         unsigned int up_threshold;
 204         unsigned int adj_up_threshold;
 205         unsigned int powersave_bias;
 206         unsigned int io_is_busy;
 207 // <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
 208         unsigned int down_differential;
 209         unsigned int cpu_up_threshold;
 210         unsigned int cpu_down_differential;
 211         unsigned int cpu_up_avg_times;
 212         unsigned int cpu_down_avg_times;
 213         unsigned int cpu_num_limit;
 214         unsigned int cpu_num_base;
 215         unsigned int is_cpu_hotplug_disable;
 216         unsigned int cpu_input_boost_enable;
 217         unsigned int cpu_input_boost_num;
 218         unsigned int cpu_rush_boost_enable;
 219         unsigned int cpu_rush_boost_num;
 220         unsigned int cpu_rush_threshold;
 221         unsigned int cpu_rush_tlp_times;
 222         unsigned int cpu_rush_avg_times;
 223 // >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
 224 };
 225
 226 /* Common Governer data across policies */
 227 struct dbs_data;
 228 struct common_dbs_data {
 229         /* Common across governors */
 230         #define GOV_ONDEMAND            0
 231         #define GOV_CONSERVATIVE        1
 232         #define GOV_HOTPLUG             2
 233         int governor;
 234         struct attribute_group *attr_group_gov_sys; /* one governor - system */
 235         struct attribute_group *attr_group_gov_pol; /* one governor - policy */
 236
 237         /* Common data for platforms that don't set have_governor_per_policy */
 238         struct dbs_data *gdbs_data;
 239
 240         struct cpu_dbs_common_info *(*get_cpu_cdbs)(int cpu);
 241         void *(*get_cpu_dbs_info_s)(int cpu);
 242         void (*gov_dbs_timer)(struct work_struct *work);
 243         void (*gov_check_cpu)(int cpu, unsigned int load);
 244         int (*init)(struct dbs_data *dbs_data);
 245         void (*exit)(struct dbs_data *dbs_data);
 246
 247         /* Governor specific ops, see below */
 248         void *gov_ops;
 249 };
 250
 251 /* Governer Per policy data */
 252 struct dbs_data {
 253         struct common_dbs_data *cdata;
 254         unsigned int min_sampling_rate;
 255         int usage_count;
 256         void *tuners;
 257
 258         /* dbs_mutex protects dbs_enable in governor start/stop */
 259         struct mutex mutex;
 260 };
 261
 262 /* Governor specific ops, will be passed to dbs_data->gov_ops */
 263 struct od_ops {
 264         void (*powersave_bias_init_cpu)(int cpu);
 265         unsigned int (*powersave_bias_target)(struct cpufreq_policy *policy,
 266                         unsigned int freq_next, unsigned int relation);
 267         void (*freq_increase)(struct cpufreq_policy *p, unsigned int freq);
 268 };
 269
 270 struct cs_ops {
 271         struct notifier_block *notifier_block;
 272 };
 273
 274 struct hp_ops {
 275         void (*powersave_bias_init_cpu)(int cpu);
 276         unsigned int (*powersave_bias_target)(struct cpufreq_policy *policy,
 277                         unsigned int freq_next, unsigned int relation);
 278         void (*freq_increase)(struct cpufreq_policy *p, unsigned int freq);
 279         struct input_handler *input_handler; // <-XXX
 280 };
 281
 282 static inline int delay_for_sampling_rate(unsigned int sampling_rate)
 283 {
 284         int delay = usecs_to_jiffies(sampling_rate);
 285
 286         /* We want all CPUs to do sampling nearly on same jiffy */
 287         if (num_online_cpus() > 1)
 288                 delay -= jiffies % delay;
 289
 290         return delay;
 291 }
 292
 293 #define declare_show_sampling_rate_min(_gov)                            \
 294 static ssize_t show_sampling_rate_min_gov_sys                           \
 295 (struct kobject *kobj, struct attribute *attr, char *buf)               \
 296 {                                                                       \
 297         struct dbs_data *dbs_data = _gov##_dbs_cdata.gdbs_data;         \
 298         return sprintf(buf, "%u\n", dbs_data->min_sampling_rate);       \
 299 }                                                                       \
 300                                                                         \
 301 static ssize_t show_sampling_rate_min_gov_pol                           \
 302 (struct cpufreq_policy *policy, char *buf)                              \
 303 {                                                                       \
 304         struct dbs_data *dbs_data = policy->governor_data;              \
 305         return sprintf(buf, "%u\n", dbs_data->min_sampling_rate);       \
 306 }
 307
 308 void dbs_check_cpu(struct dbs_data *dbs_data, int cpu);
 309 bool need_load_eval(struct cpu_dbs_common_info *cdbs,
 310                 unsigned int sampling_rate);
 311 int cpufreq_governor_dbs(struct cpufreq_policy *policy,
 312                 struct common_dbs_data *cdata, unsigned int event);
 313 void gov_queue_work(struct dbs_data *dbs_data, struct cpufreq_policy *policy,
 314                 unsigned int delay, bool all_cpus);
 315 void od_register_powersave_bias_handler(unsigned int (*f)
 316                 (struct cpufreq_policy *, unsigned int, unsigned int),
 317                 unsigned int powersave_bias);
 318 void od_unregister_powersave_bias_handler(void);
 319 void hp_register_powersave_bias_handler(unsigned int (*f)
 320                 (struct cpufreq_policy *, unsigned int, unsigned int),
 321                 unsigned int powersave_bias);
 322 void hp_unregister_powersave_bias_handler(void);
 323 #endif /* _CPUFREQ_GOVERNOR_H */