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/atomic.h> 21 #include <linux/irq_work.h> 22 #include <linux/cpufreq.h> 23 #include <linux/sched/cpufreq.h> 24 #include <linux/kernel_stat.h> 25 #include <linux/module.h> 26 #include <linux/mutex.h> 27 28 /* Ondemand Sampling types */ 29 enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE}; 30 31 /* 32 * Abbreviations: 33 * dbs: used as a shortform for demand based switching It helps to keep variable 34 * names smaller, simpler 35 * cdbs: common dbs 36 * od_*: On-demand governor 37 * cs_*: Conservative governor 38 */ 39 40 /* Governor demand based switching data (per-policy or global). */ 41 struct dbs_data { 42 struct gov_attr_set attr_set; 43 void *tuners; 44 unsigned int ignore_nice_load; 45 unsigned int sampling_rate; 46 unsigned int sampling_down_factor; 47 unsigned int up_threshold; 48 unsigned int io_is_busy; 49 }; 50 51 static inline struct dbs_data *to_dbs_data(struct gov_attr_set *attr_set) 52 { 53 return container_of(attr_set, struct dbs_data, attr_set); 54 } 55 56 #define gov_show_one(_gov, file_name) \ 57 static ssize_t show_##file_name \ 58 (struct gov_attr_set *attr_set, char *buf) \ 59 { \ 60 struct dbs_data *dbs_data = to_dbs_data(attr_set); \ 61 struct _gov##_dbs_tuners *tuners = dbs_data->tuners; \ 62 return sprintf(buf, "%u\n", tuners->file_name); \ 63 } 64 65 #define gov_show_one_common(file_name) \ 66 static ssize_t show_##file_name \ 67 (struct gov_attr_set *attr_set, char *buf) \ 68 { \ 69 struct dbs_data *dbs_data = to_dbs_data(attr_set); \ 70 return sprintf(buf, "%u\n", dbs_data->file_name); \ 71 } 72 73 #define gov_attr_ro(_name) \ 74 static struct governor_attr _name = \ 75 __ATTR(_name, 0444, show_##_name, NULL) 76 77 #define gov_attr_rw(_name) \ 78 static struct governor_attr _name = \ 79 __ATTR(_name, 0644, show_##_name, store_##_name) 80 81 /* Common to all CPUs of a policy */ 82 struct policy_dbs_info { 83 struct cpufreq_policy *policy; 84 /* 85 * Per policy mutex that serializes load evaluation from limit-change 86 * and work-handler. 87 */ 88 struct mutex update_mutex; 89 90 u64 last_sample_time; 91 s64 sample_delay_ns; 92 atomic_t work_count; 93 struct irq_work irq_work; 94 struct work_struct work; 95 /* dbs_data may be shared between multiple policy objects */ 96 struct dbs_data *dbs_data; 97 struct list_head list; 98 /* Multiplier for increasing sample delay temporarily. */ 99 unsigned int rate_mult; 100 unsigned int idle_periods; /* For conservative */ 101 /* Status indicators */ 102 bool is_shared; /* This object is used by multiple CPUs */ 103 bool work_in_progress; /* Work is being queued up or in progress */ 104 }; 105 106 static inline void gov_update_sample_delay(struct policy_dbs_info *policy_dbs, 107 unsigned int delay_us) 108 { 109 policy_dbs->sample_delay_ns = delay_us * NSEC_PER_USEC; 110 } 111 112 /* Per cpu structures */ 113 struct cpu_dbs_info { 114 u64 prev_cpu_idle; 115 u64 prev_update_time; 116 u64 prev_cpu_nice; 117 /* 118 * Used to keep track of load in the previous interval. However, when 119 * explicitly set to zero, it is used as a flag to ensure that we copy 120 * the previous load to the current interval only once, upon the first 121 * wake-up from idle. 122 */ 123 unsigned int prev_load; 124 struct update_util_data update_util; 125 struct policy_dbs_info *policy_dbs; 126 }; 127 128 /* Common Governor data across policies */ 129 struct dbs_governor { 130 struct cpufreq_governor gov; 131 struct kobj_type kobj_type; 132 133 /* 134 * Common data for platforms that don't set 135 * CPUFREQ_HAVE_GOVERNOR_PER_POLICY 136 */ 137 struct dbs_data *gdbs_data; 138 139 unsigned int (*gov_dbs_update)(struct cpufreq_policy *policy); 140 struct policy_dbs_info *(*alloc)(void); 141 void (*free)(struct policy_dbs_info *policy_dbs); 142 int (*init)(struct dbs_data *dbs_data); 143 void (*exit)(struct dbs_data *dbs_data); 144 void (*start)(struct cpufreq_policy *policy); 145 }; 146 147 static inline struct dbs_governor *dbs_governor_of(struct cpufreq_policy *policy) 148 { 149 return container_of(policy->governor, struct dbs_governor, gov); 150 } 151 152 /* Governor callback routines */ 153 int cpufreq_dbs_governor_init(struct cpufreq_policy *policy); 154 void cpufreq_dbs_governor_exit(struct cpufreq_policy *policy); 155 int cpufreq_dbs_governor_start(struct cpufreq_policy *policy); 156 void cpufreq_dbs_governor_stop(struct cpufreq_policy *policy); 157 void cpufreq_dbs_governor_limits(struct cpufreq_policy *policy); 158 159 #define CPUFREQ_DBS_GOVERNOR_INITIALIZER(_name_) \ 160 { \ 161 .name = _name_, \ 162 .dynamic_switching = true, \ 163 .owner = THIS_MODULE, \ 164 .init = cpufreq_dbs_governor_init, \ 165 .exit = cpufreq_dbs_governor_exit, \ 166 .start = cpufreq_dbs_governor_start, \ 167 .stop = cpufreq_dbs_governor_stop, \ 168 .limits = cpufreq_dbs_governor_limits, \ 169 } 170 171 /* Governor specific operations */ 172 struct od_ops { 173 unsigned int (*powersave_bias_target)(struct cpufreq_policy *policy, 174 unsigned int freq_next, unsigned int relation); 175 }; 176 177 unsigned int dbs_update(struct cpufreq_policy *policy); 178 void od_register_powersave_bias_handler(unsigned int (*f) 179 (struct cpufreq_policy *, unsigned int, unsigned int), 180 unsigned int powersave_bias); 181 void od_unregister_powersave_bias_handler(void); 182 ssize_t store_sampling_rate(struct gov_attr_set *attr_set, const char *buf, 183 size_t count); 184 void gov_update_cpu_data(struct dbs_data *dbs_data); 185 #endif /* _CPUFREQ_GOVERNOR_H */ 186