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 #include <linux/sysfs.h> 25 26 /* Ondemand Sampling types */ 27 enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE}; 28 29 /* 30 * Abbreviations: 31 * dbs: used as a shortform for demand based switching It helps to keep variable 32 * names smaller, simpler 33 * cdbs: common dbs 34 * od_*: On-demand governor 35 * cs_*: Conservative governor 36 */ 37 38 /* Governor demand based switching data (per-policy or global). */ 39 struct dbs_data { 40 struct gov_attr_set attr_set; 41 struct dbs_governor *gov; 42 void *tuners; 43 unsigned int ignore_nice_load; 44 unsigned int sampling_rate; 45 unsigned int sampling_down_factor; 46 unsigned int up_threshold; 47 unsigned int io_is_busy; 48 }; 49 50 static inline struct dbs_data *to_dbs_data(struct gov_attr_set *attr_set) 51 { 52 return container_of(attr_set, struct dbs_data, attr_set); 53 } 54 55 #define gov_show_one(_gov, file_name) \ 56 static ssize_t file_name##_show \ 57 (struct gov_attr_set *attr_set, char *buf) \ 58 { \ 59 struct dbs_data *dbs_data = to_dbs_data(attr_set); \ 60 struct _gov##_dbs_tuners *tuners = dbs_data->tuners; \ 61 return sysfs_emit(buf, "%u\n", tuners->file_name); \ 62 } 63 64 #define gov_show_one_common(file_name) \ 65 static ssize_t file_name##_show \ 66 (struct gov_attr_set *attr_set, char *buf) \ 67 { \ 68 struct dbs_data *dbs_data = to_dbs_data(attr_set); \ 69 return sysfs_emit(buf, "%u\n", dbs_data->file_name); \ 70 } 71 72 #define gov_attr_ro(_name) \ 73 static struct governor_attr _name = __ATTR_RO(_name) 74 75 #define gov_attr_rw(_name) \ 76 static struct governor_attr _name = __ATTR_RW(_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 /* Maximum load from the current policy sample. */ 99 unsigned int max_sample_load; 100 /* Status indicators */ 101 bool is_shared; /* This object is used by multiple CPUs */ 102 bool work_in_progress; /* Work is being queued up or in progress */ 103 }; 104 105 static inline void gov_update_sample_delay(struct policy_dbs_info *policy_dbs, 106 unsigned int delay_us) 107 { 108 policy_dbs->sample_delay_ns = delay_us * NSEC_PER_USEC; 109 } 110 111 /* Per cpu structures */ 112 struct cpu_dbs_info { 113 u64 prev_cpu_idle; 114 u64 prev_update_time; 115 u64 prev_cpu_nice; 116 /* 117 * Used to keep track of load in the previous interval. However, when 118 * explicitly set to zero, it is used as a flag to ensure that we copy 119 * the previous load to the current interval only once, upon the first 120 * wake-up from idle. 121 */ 122 unsigned int prev_load; 123 struct update_util_data update_util; 124 struct policy_dbs_info *policy_dbs; 125 }; 126 127 /* Common Governor data across policies */ 128 struct dbs_governor { 129 struct cpufreq_governor gov; 130 struct kobj_type kobj_type; 131 132 /* 133 * Common data for platforms that don't set 134 * CPUFREQ_HAVE_GOVERNOR_PER_POLICY 135 */ 136 struct dbs_data *gdbs_data; 137 138 unsigned int (*gov_dbs_update)(struct cpufreq_policy *policy); 139 struct policy_dbs_info *(*alloc)(void); 140 void (*free)(struct policy_dbs_info *policy_dbs); 141 int (*init)(struct dbs_data *dbs_data); 142 void (*exit)(struct dbs_data *dbs_data); 143 void (*start)(struct cpufreq_policy *policy); 144 void (*limits)(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 .flags = CPUFREQ_GOV_DYNAMIC_SWITCHING, \ 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 sampling_rate_store(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