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1/* SPDX-License-Identifier: GPL-2.0-only */2/*3 * drivers/cpufreq/cpufreq_governor.h4 *5 * Header file for CPUFreq governors common code6 *7 * Copyright (C) 2001 Russell King8 * (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.9 * (C) 2003 Jun Nakajima <jun.nakajima@intel.com>10 * (C) 2009 Alexander Clouter <alex@digriz.org.uk>11 * (c) 2012 Viresh Kumar <viresh.kumar@linaro.org>12 */13 14#ifndef _CPUFREQ_GOVERNOR_H15#define _CPUFREQ_GOVERNOR_H16 17#include <linux/atomic.h>18#include <linux/irq_work.h>19#include <linux/cpufreq.h>20#include <linux/sched/cpufreq.h>21#include <linux/kernel_stat.h>22#include <linux/module.h>23#include <linux/mutex.h>24 25/* Ondemand Sampling types */26enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE};27 28/*29 * Abbreviations:30 * dbs: used as a shortform for demand based switching It helps to keep variable31 * names smaller, simpler32 * cdbs: common dbs33 * od_*: On-demand governor34 * cs_*: Conservative governor35 */36 37/* Governor demand based switching data (per-policy or global). */38struct dbs_data {39 struct gov_attr_set attr_set;40 struct dbs_governor *gov;41 void *tuners;42 unsigned int ignore_nice_load;43 unsigned int sampling_rate;44 unsigned int sampling_down_factor;45 unsigned int up_threshold;46 unsigned int io_is_busy;47};48 49static inline struct dbs_data *to_dbs_data(struct gov_attr_set *attr_set)50{51 return container_of(attr_set, struct dbs_data, attr_set);52}53 54#define gov_show_one(_gov, file_name) \55static ssize_t file_name##_show \56(struct gov_attr_set *attr_set, char *buf) \57{ \58 struct dbs_data *dbs_data = to_dbs_data(attr_set); \59 struct _gov##_dbs_tuners *tuners = dbs_data->tuners; \60 return sprintf(buf, "%u\n", tuners->file_name); \61}62 63#define gov_show_one_common(file_name) \64static ssize_t file_name##_show \65(struct gov_attr_set *attr_set, char *buf) \66{ \67 struct dbs_data *dbs_data = to_dbs_data(attr_set); \68 return sprintf(buf, "%u\n", dbs_data->file_name); \69}70 71#define gov_attr_ro(_name) \72static struct governor_attr _name = __ATTR_RO(_name)73 74#define gov_attr_rw(_name) \75static struct governor_attr _name = __ATTR_RW(_name)76 77/* Common to all CPUs of a policy */78struct policy_dbs_info {79 struct cpufreq_policy *policy;80 /*81 * Per policy mutex that serializes load evaluation from limit-change82 * and work-handler.83 */84 struct mutex update_mutex;85 86 u64 last_sample_time;87 s64 sample_delay_ns;88 atomic_t work_count;89 struct irq_work irq_work;90 struct work_struct work;91 /* dbs_data may be shared between multiple policy objects */92 struct dbs_data *dbs_data;93 struct list_head list;94 /* Multiplier for increasing sample delay temporarily. */95 unsigned int rate_mult;96 unsigned int idle_periods; /* For conservative */97 /* Status indicators */98 bool is_shared; /* This object is used by multiple CPUs */99 bool work_in_progress; /* Work is being queued up or in progress */100};101 102static inline void gov_update_sample_delay(struct policy_dbs_info *policy_dbs,103 unsigned int delay_us)104{105 policy_dbs->sample_delay_ns = delay_us * NSEC_PER_USEC;106}107 108/* Per cpu structures */109struct cpu_dbs_info {110 u64 prev_cpu_idle;111 u64 prev_update_time;112 u64 prev_cpu_nice;113 /*114 * Used to keep track of load in the previous interval. However, when115 * explicitly set to zero, it is used as a flag to ensure that we copy116 * the previous load to the current interval only once, upon the first117 * wake-up from idle.118 */119 unsigned int prev_load;120 struct update_util_data update_util;121 struct policy_dbs_info *policy_dbs;122};123 124/* Common Governor data across policies */125struct dbs_governor {126 struct cpufreq_governor gov;127 struct kobj_type kobj_type;128 129 /*130 * Common data for platforms that don't set131 * CPUFREQ_HAVE_GOVERNOR_PER_POLICY132 */133 struct dbs_data *gdbs_data;134 135 unsigned int (*gov_dbs_update)(struct cpufreq_policy *policy);136 struct policy_dbs_info *(*alloc)(void);137 void (*free)(struct policy_dbs_info *policy_dbs);138 int (*init)(struct dbs_data *dbs_data);139 void (*exit)(struct dbs_data *dbs_data);140 void (*start)(struct cpufreq_policy *policy);141};142 143static inline struct dbs_governor *dbs_governor_of(struct cpufreq_policy *policy)144{145 return container_of(policy->governor, struct dbs_governor, gov);146}147 148/* Governor callback routines */149int cpufreq_dbs_governor_init(struct cpufreq_policy *policy);150void cpufreq_dbs_governor_exit(struct cpufreq_policy *policy);151int cpufreq_dbs_governor_start(struct cpufreq_policy *policy);152void cpufreq_dbs_governor_stop(struct cpufreq_policy *policy);153void cpufreq_dbs_governor_limits(struct cpufreq_policy *policy);154 155#define CPUFREQ_DBS_GOVERNOR_INITIALIZER(_name_) \156 { \157 .name = _name_, \158 .flags = CPUFREQ_GOV_DYNAMIC_SWITCHING, \159 .owner = THIS_MODULE, \160 .init = cpufreq_dbs_governor_init, \161 .exit = cpufreq_dbs_governor_exit, \162 .start = cpufreq_dbs_governor_start, \163 .stop = cpufreq_dbs_governor_stop, \164 .limits = cpufreq_dbs_governor_limits, \165 }166 167/* Governor specific operations */168struct od_ops {169 unsigned int (*powersave_bias_target)(struct cpufreq_policy *policy,170 unsigned int freq_next, unsigned int relation);171};172 173unsigned int dbs_update(struct cpufreq_policy *policy);174void od_register_powersave_bias_handler(unsigned int (*f)175 (struct cpufreq_policy *, unsigned int, unsigned int),176 unsigned int powersave_bias);177void od_unregister_powersave_bias_handler(void);178ssize_t sampling_rate_store(struct gov_attr_set *attr_set, const char *buf,179 size_t count);180void gov_update_cpu_data(struct dbs_data *dbs_data);181#endif /* _CPUFREQ_GOVERNOR_H */182