1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * drivers/cpufreq/cpufreq_governor.h 4 * 5 * Header file for CPUFreq governors common code 6 * 7 * Copyright (C) 2001 Russell King 8 * (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_H 15 #define _CPUFREQ_GOVERNOR_H 16 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 */ 26 enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE}; 27 28 /* 29 * Abbreviations: 30 * dbs: used as a shortform for demand based switching It helps to keep variable 31 * names smaller, simpler 32 * cdbs: common dbs 33 * od_*: On-demand governor 34 * cs_*: Conservative governor 35 */ 36 37 /* Governor demand based switching data (per-policy or global). */ 38 struct dbs_data { 39 struct gov_attr_set attr_set; 40 void *tuners; 41 unsigned int ignore_nice_load; 42 unsigned int sampling_rate; 43 unsigned int sampling_down_factor; 44 unsigned int up_threshold; 45 unsigned int io_is_busy; 46 }; 47 48 static inline struct dbs_data *to_dbs_data(struct gov_attr_set *attr_set) 49 { 50 return container_of(attr_set, struct dbs_data, attr_set); 51 } 52 53 #define gov_show_one(_gov, file_name) \ 54 static ssize_t show_##file_name \ 55 (struct gov_attr_set *attr_set, char *buf) \ 56 { \ 57 struct dbs_data *dbs_data = to_dbs_data(attr_set); \ 58 struct _gov##_dbs_tuners *tuners = dbs_data->tuners; \ 59 return sprintf(buf, "%u\n", tuners->file_name); \ 60 } 61 62 #define gov_show_one_common(file_name) \ 63 static ssize_t show_##file_name \ 64 (struct gov_attr_set *attr_set, char *buf) \ 65 { \ 66 struct dbs_data *dbs_data = to_dbs_data(attr_set); \ 67 return sprintf(buf, "%u\n", dbs_data->file_name); \ 68 } 69 70 #define gov_attr_ro(_name) \ 71 static struct governor_attr _name = \ 72 __ATTR(_name, 0444, show_##_name, NULL) 73 74 #define gov_attr_rw(_name) \ 75 static struct governor_attr _name = \ 76 __ATTR(_name, 0644, show_##_name, store_##_name) 77 78 /* Common to all CPUs of a policy */ 79 struct policy_dbs_info { 80 struct cpufreq_policy *policy; 81 /* 82 * Per policy mutex that serializes load evaluation from limit-change 83 * and work-handler. 84 */ 85 struct mutex update_mutex; 86 87 u64 last_sample_time; 88 s64 sample_delay_ns; 89 atomic_t work_count; 90 struct irq_work irq_work; 91 struct work_struct work; 92 /* dbs_data may be shared between multiple policy objects */ 93 struct dbs_data *dbs_data; 94 struct list_head list; 95 /* Multiplier for increasing sample delay temporarily. */ 96 unsigned int rate_mult; 97 unsigned int idle_periods; /* For conservative */ 98 /* Status indicators */ 99 bool is_shared; /* This object is used by multiple CPUs */ 100 bool work_in_progress; /* Work is being queued up or in progress */ 101 }; 102 103 static inline void gov_update_sample_delay(struct policy_dbs_info *policy_dbs, 104 unsigned int delay_us) 105 { 106 policy_dbs->sample_delay_ns = delay_us * NSEC_PER_USEC; 107 } 108 109 /* Per cpu structures */ 110 struct cpu_dbs_info { 111 u64 prev_cpu_idle; 112 u64 prev_update_time; 113 u64 prev_cpu_nice; 114 /* 115 * Used to keep track of load in the previous interval. However, when 116 * explicitly set to zero, it is used as a flag to ensure that we copy 117 * the previous load to the current interval only once, upon the first 118 * wake-up from idle. 119 */ 120 unsigned int prev_load; 121 struct update_util_data update_util; 122 struct policy_dbs_info *policy_dbs; 123 }; 124 125 /* Common Governor data across policies */ 126 struct dbs_governor { 127 struct cpufreq_governor gov; 128 struct kobj_type kobj_type; 129 130 /* 131 * Common data for platforms that don't set 132 * CPUFREQ_HAVE_GOVERNOR_PER_POLICY 133 */ 134 struct dbs_data *gdbs_data; 135 136 unsigned int (*gov_dbs_update)(struct cpufreq_policy *policy); 137 struct policy_dbs_info *(*alloc)(void); 138 void (*free)(struct policy_dbs_info *policy_dbs); 139 int (*init)(struct dbs_data *dbs_data); 140 void (*exit)(struct dbs_data *dbs_data); 141 void (*start)(struct cpufreq_policy *policy); 142 }; 143 144 static inline struct dbs_governor *dbs_governor_of(struct cpufreq_policy *policy) 145 { 146 return container_of(policy->governor, struct dbs_governor, gov); 147 } 148 149 /* Governor callback routines */ 150 int cpufreq_dbs_governor_init(struct cpufreq_policy *policy); 151 void cpufreq_dbs_governor_exit(struct cpufreq_policy *policy); 152 int cpufreq_dbs_governor_start(struct cpufreq_policy *policy); 153 void cpufreq_dbs_governor_stop(struct cpufreq_policy *policy); 154 void cpufreq_dbs_governor_limits(struct cpufreq_policy *policy); 155 156 #define CPUFREQ_DBS_GOVERNOR_INITIALIZER(_name_) \ 157 { \ 158 .name = _name_, \ 159 .dynamic_switching = true, \ 160 .owner = THIS_MODULE, \ 161 .init = cpufreq_dbs_governor_init, \ 162 .exit = cpufreq_dbs_governor_exit, \ 163 .start = cpufreq_dbs_governor_start, \ 164 .stop = cpufreq_dbs_governor_stop, \ 165 .limits = cpufreq_dbs_governor_limits, \ 166 } 167 168 /* Governor specific operations */ 169 struct od_ops { 170 unsigned int (*powersave_bias_target)(struct cpufreq_policy *policy, 171 unsigned int freq_next, unsigned int relation); 172 }; 173 174 unsigned int dbs_update(struct cpufreq_policy *policy); 175 void od_register_powersave_bias_handler(unsigned int (*f) 176 (struct cpufreq_policy *, unsigned int, unsigned int), 177 unsigned int powersave_bias); 178 void od_unregister_powersave_bias_handler(void); 179 ssize_t store_sampling_rate(struct gov_attr_set *attr_set, const char *buf, 180 size_t count); 181 void gov_update_cpu_data(struct dbs_data *dbs_data); 182 #endif /* _CPUFREQ_GOVERNOR_H */ 183