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 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 49 static 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) \ 55 static 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) \ 64 static 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) \ 72 static struct governor_attr _name = __ATTR_RO(_name) 73 74 #define gov_attr_rw(_name) \ 75 static struct governor_attr _name = __ATTR_RW(_name) 76 77 /* Common to all CPUs of a policy */ 78 struct policy_dbs_info { 79 struct cpufreq_policy *policy; 80 /* 81 * Per policy mutex that serializes load evaluation from limit-change 82 * 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 }; 101 102 static 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 */ 109 struct 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, when 115 * explicitly set to zero, it is used as a flag to ensure that we copy 116 * the previous load to the current interval only once, upon the first 117 * 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 */ 125 struct dbs_governor { 126 struct cpufreq_governor gov; 127 struct kobj_type kobj_type; 128 129 /* 130 * Common data for platforms that don't set 131 * CPUFREQ_HAVE_GOVERNOR_PER_POLICY 132 */ 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 }; 142 143 static 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 */ 149 int cpufreq_dbs_governor_init(struct cpufreq_policy *policy); 150 void cpufreq_dbs_governor_exit(struct cpufreq_policy *policy); 151 int cpufreq_dbs_governor_start(struct cpufreq_policy *policy); 152 void cpufreq_dbs_governor_stop(struct cpufreq_policy *policy); 153 void 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 */ 168 struct od_ops { 169 unsigned int (*powersave_bias_target)(struct cpufreq_policy *policy, 170 unsigned int freq_next, unsigned int relation); 171 }; 172 173 unsigned int dbs_update(struct cpufreq_policy *policy); 174 void od_register_powersave_bias_handler(unsigned int (*f) 175 (struct cpufreq_policy *, unsigned int, unsigned int), 176 unsigned int powersave_bias); 177 void od_unregister_powersave_bias_handler(void); 178 ssize_t sampling_rate_store(struct gov_attr_set *attr_set, const char *buf, 179 size_t count); 180 void gov_update_cpu_data(struct dbs_data *dbs_data); 181 #endif /* _CPUFREQ_GOVERNOR_H */ 182