/*
* 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>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef _CPUFREQ_GOVERNOR_H
#define _CPUFREQ_GOVERNOR_H
#include <linux/cpufreq.h>
#include <linux/kernel_stat.h>
#include <linux/module.h>
#include <linux/mutex.h>
/*
* The polling frequency depends on the capability of the processor. Default
* polling frequency is 1000 times the transition latency of the processor. The
* governor will work on any processor with transition latency <= 10ms, using
* appropriate sampling rate.
*
* For CPUs with transition latency > 10ms (mostly drivers with CPUFREQ_ETERNAL)
* this governor will not work. All times here are in us (micro seconds).
*/
#define MIN_SAMPLING_RATE_RATIO (2)
#define LATENCY_MULTIPLIER (1000)
#define MIN_LATENCY_MULTIPLIER (20)
#define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000)
/* Ondemand Sampling types */
enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE};
/*
* Macro for creating governors sysfs routines
*
* - gov_sys: One governor instance per whole system
* - gov_pol: One governor instance per policy
*/
/* Create attributes */
#define gov_sys_attr_ro(_name) \
static struct global_attr _name##_gov_sys = \
__ATTR(_name, 0444, show_##_name##_gov_sys, NULL)
#define gov_sys_attr_rw(_name) \
static struct global_attr _name##_gov_sys = \
__ATTR(_name, 0644, show_##_name##_gov_sys, store_##_name##_gov_sys)
#define gov_pol_attr_ro(_name) \
static struct freq_attr _name##_gov_pol = \
__ATTR(_name, 0444, show_##_name##_gov_pol, NULL)
#define gov_pol_attr_rw(_name) \
static struct freq_attr _name##_gov_pol = \
__ATTR(_name, 0644, show_##_name##_gov_pol, store_##_name##_gov_pol)
#define gov_sys_pol_attr_rw(_name) \
gov_sys_attr_rw(_name); \
gov_pol_attr_rw(_name)
#define gov_sys_pol_attr_ro(_name) \
gov_sys_attr_ro(_name); \
gov_pol_attr_ro(_name)
/* Create show/store routines */
#define show_one(_gov, file_name) \
static ssize_t show_##file_name##_gov_sys \
(struct kobject *kobj, struct attribute *attr, char *buf) \
{ \
struct _gov##_dbs_tuners *tuners = _gov##_dbs_cdata.gdbs_data->tuners; \
return sprintf(buf, "%u\n", tuners->file_name); \
} \
\
static ssize_t show_##file_name##_gov_pol \
(struct cpufreq_policy *policy, char *buf) \
{ \
struct dbs_data *dbs_data = policy->governor_data; \
struct _gov##_dbs_tuners *tuners = dbs_data->tuners; \
return sprintf(buf, "%u\n", tuners->file_name); \
}
#define store_one(_gov, file_name) \
static ssize_t store_##file_name##_gov_sys \
(struct kobject *kobj, struct attribute *attr, const char *buf, size_t count) \
{ \
struct dbs_data *dbs_data = _gov##_dbs_cdata.gdbs_data; \
return store_##file_name(dbs_data, buf, count); \
} \
\
static ssize_t store_##file_name##_gov_pol \
(struct cpufreq_policy *policy, const char *buf, size_t count) \
{ \
struct dbs_data *dbs_data = policy->governor_data; \
return store_##file_name(dbs_data, buf, count); \
}
#define show_store_one(_gov, file_name) \
show_one(_gov, file_name); \
store_one(_gov, file_name)
/* create helper routines */
#define define_get_cpu_dbs_routines(_dbs_info) \
static struct cpu_dbs_common_info *get_cpu_cdbs(int cpu) \
{ \
return &per_cpu(_dbs_info, cpu).cdbs; \
} \
\
static void *get_cpu_dbs_info_s(int cpu) \
{ \
return &per_cpu(_dbs_info, cpu); \
}
/*
* 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
*/
/* Per cpu structures */
struct cpu_dbs_common_info {
int cpu;
u64 prev_cpu_idle;
u64 prev_cpu_wall;
u64 prev_cpu_nice;
struct cpufreq_policy *cur_policy;
struct delayed_work work;
/*
* percpu mutex that serializes governor limit change with gov_dbs_timer
* invocation. We do not want gov_dbs_timer to run when user is changing
* the governor or limits.
*/
struct mutex timer_mutex;
ktime_t time_stamp;
};
struct od_cpu_dbs_info_s {
struct cpu_dbs_common_info cdbs;
struct cpufreq_frequency_table *freq_table;
unsigned int freq_lo;
unsigned int freq_lo_jiffies;
unsigned int freq_hi_jiffies;
unsigned int rate_mult;
unsigned int sample_type:1;
};
struct cs_cpu_dbs_info_s {
struct cpu_dbs_common_info cdbs;
unsigned int down_skip;
unsigned int requested_freq;
unsigned int enable:1;
};
/* Per policy Governors sysfs tunables */
struct od_dbs_tuners {
unsigned int ignore_nice_load;
unsigned int sampling_rate;
unsigned int sampling_down_factor;
unsigned int up_threshold;
unsigned int powersave_bias;
unsigned int io_is_busy;
};
struct cs_dbs_tuners {
unsigned int ignore_nice_load;
unsigned int sampling_rate;
unsigned int sampling_down_factor;
unsigned int up_threshold;
unsigned int down_threshold;
unsigned int freq_step;
};
/* Common Governor data across policies */
struct dbs_data;
struct common_dbs_data {
/* Common across governors */
#define GOV_ONDEMAND 0
#define GOV_CONSERVATIVE 1
int governor;
struct attribute_group *attr_group_gov_sys; /* one governor - system */
struct attribute_group *attr_group_gov_pol; /* one governor - policy */
/* Common data for platforms that don't set have_governor_per_policy */
struct dbs_data *gdbs_data;
struct cpu_dbs_common_info *(*get_cpu_cdbs)(int cpu);
void *(*get_cpu_dbs_info_s)(int cpu);
void (*gov_dbs_timer)(struct work_struct *work);
void (*gov_check_cpu)(int cpu, unsigned int load);
int (*init)(struct dbs_data *dbs_data);
void (*exit)(struct dbs_data *dbs_data);
/* Governor specific ops, see below */
void *gov_ops;
};
/* Governor Per policy data */
struct dbs_data {
struct common_dbs_data *cdata;
unsigned int min_sampling_rate;
int usage_count;
void *tuners;
/* dbs_mutex protects dbs_enable in governor start/stop */
struct mutex mutex;
};
/* Governor specific ops, will be passed to dbs_data->gov_ops */
struct od_ops {
void (*powersave_bias_init_cpu)(int cpu);
unsigned int (*powersave_bias_target)(struct cpufreq_policy *policy,
unsigned int freq_next, unsigned int relation);
void (*freq_increase)(struct cpufreq_policy *policy, unsigned int freq);
};
struct cs_ops {
struct notifier_block *notifier_block;
};
static inline int delay_for_sampling_rate(unsigned int sampling_rate)
{
int delay = usecs_to_jiffies(sampling_rate);
/* We want all CPUs to do sampling nearly on same jiffy */
if (num_online_cpus() > 1)
delay -= jiffies % delay;
return delay;
}
#define declare_show_sampling_rate_min(_gov) \
static ssize_t show_sampling_rate_min_gov_sys \
(struct kobject *kobj, struct attribute *attr, char *buf) \
{ \
struct dbs_data *dbs_data = _gov##_dbs_cdata.gdbs_data; \
return sprintf(buf, "%u\n", dbs_data->min_sampling_rate); \
} \
\
static ssize_t show_sampling_rate_min_gov_pol \
(struct cpufreq_policy *policy, char *buf) \
{ \
struct dbs_data *dbs_data = policy->governor_data; \
return sprintf(buf, "%u\n", dbs_data->min_sampling_rate); \
}
void dbs_check_cpu(struct dbs_data *dbs_data, int cpu);
bool need_load_eval(struct cpu_dbs_common_info *cdbs,
unsigned int sampling_rate);
int cpufreq_governor_dbs(struct cpufreq_policy *policy,
struct common_dbs_data *cdata, unsigned int event);
void gov_queue_work(struct dbs_data *dbs_data, struct cpufreq_policy *policy,
unsigned int delay, bool all_cpus);
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);
#endif /* _CPUFREQ_GOVERNOR_H */
