/* * drivers/cpufreq/cpufreq_governor.h * * Header file for CPUFreq governors common code * * Copyright (C) 2001 Russell King * (C) 2003 Venkatesh Pallipadi . * (C) 2003 Jun Nakajima * (C) 2009 Alexander Clouter * (c) 2012 Viresh Kumar * * 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 #include #include #include #include #include /* * 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}; /* create helper routines */ #define define_get_cpu_dbs_routines(_dbs_info) \ static struct cpu_dbs_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 */ /* Governor demand based switching data (per-policy or global). */ struct dbs_data { int usage_count; void *tuners; unsigned int min_sampling_rate; unsigned int ignore_nice_load; unsigned int sampling_rate; unsigned int sampling_down_factor; unsigned int up_threshold; struct kobject kobj; struct list_head policy_dbs_list; /* * Protect concurrent updates to governor tunables from sysfs, * policy_dbs_list and usage_count. */ struct mutex mutex; }; /* Governor's specific attributes */ struct dbs_data; struct governor_attr { struct attribute attr; ssize_t (*show)(struct dbs_data *dbs_data, char *buf); ssize_t (*store)(struct dbs_data *dbs_data, const char *buf, size_t count); }; #define gov_show_one(_gov, file_name) \ static ssize_t show_##file_name \ (struct dbs_data *dbs_data, char *buf) \ { \ struct _gov##_dbs_tuners *tuners = dbs_data->tuners; \ return sprintf(buf, "%u\n", tuners->file_name); \ } #define gov_show_one_common(file_name) \ static ssize_t show_##file_name \ (struct dbs_data *dbs_data, char *buf) \ { \ return sprintf(buf, "%u\n", dbs_data->file_name); \ } #define gov_attr_ro(_name) \ static struct governor_attr _name = \ __ATTR(_name, 0444, show_##_name, NULL) #define gov_attr_rw(_name) \ static struct governor_attr _name = \ __ATTR(_name, 0644, show_##_name, store_##_name) /* Common to all CPUs of a policy */ struct policy_dbs_info { struct cpufreq_policy *policy; /* * Per policy mutex that serializes load evaluation from limit-change * and work-handler. */ struct mutex timer_mutex; u64 last_sample_time; s64 sample_delay_ns; atomic_t work_count; struct irq_work irq_work; struct work_struct work; /* dbs_data may be shared between multiple policy objects */ struct dbs_data *dbs_data; struct list_head list; }; static inline void gov_update_sample_delay(struct policy_dbs_info *policy_dbs, unsigned int delay_us) { policy_dbs->sample_delay_ns = delay_us * NSEC_PER_USEC; } /* Per cpu structures */ struct cpu_dbs_info { u64 prev_cpu_idle; u64 prev_cpu_wall; u64 prev_cpu_nice; /* * Used to keep track of load in the previous interval. However, when * explicitly set to zero, it is used as a flag to ensure that we copy * the previous load to the current interval only once, upon the first * wake-up from idle. */ unsigned int prev_load; struct update_util_data update_util; struct policy_dbs_info *policy_dbs; }; struct od_cpu_dbs_info_s { struct cpu_dbs_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_info cdbs; unsigned int down_skip; unsigned int requested_freq; }; /* Per policy Governors sysfs tunables */ struct od_dbs_tuners { unsigned int powersave_bias; unsigned int io_is_busy; }; struct cs_dbs_tuners { unsigned int down_threshold; unsigned int freq_step; }; /* Common Governor data across policies */ struct dbs_governor { struct cpufreq_governor gov; #define GOV_ONDEMAND 0 #define GOV_CONSERVATIVE 1 int governor; struct kobj_type kobj_type; /* * Common data for platforms that don't set * CPUFREQ_HAVE_GOVERNOR_PER_POLICY */ struct dbs_data *gdbs_data; struct cpu_dbs_info *(*get_cpu_cdbs)(int cpu); void *(*get_cpu_dbs_info_s)(int cpu); unsigned int (*gov_dbs_timer)(struct cpufreq_policy *policy); void (*gov_check_cpu)(int cpu, unsigned int load); int (*init)(struct dbs_data *dbs_data, bool notify); void (*exit)(struct dbs_data *dbs_data, bool notify); /* Governor specific ops, see below */ void *gov_ops; }; static inline struct dbs_governor *dbs_governor_of(struct cpufreq_policy *policy) { return container_of(policy->governor, struct dbs_governor, gov); } /* 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); }; 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; } extern struct mutex dbs_data_mutex; extern struct mutex cpufreq_governor_lock; void dbs_check_cpu(struct cpufreq_policy *policy); int cpufreq_governor_dbs(struct cpufreq_policy *policy, unsigned int event); 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 */