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/kernel_stat.h> 24 #include <linux/module.h> 25 #include <linux/mutex.h> 26 27 /* Ondemand Sampling types */ 28 enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE}; 29 30 /* 31 * Abbreviations: 32 * dbs: used as a shortform for demand based switching It helps to keep variable 33 * names smaller, simpler 34 * cdbs: common dbs 35 * od_*: On-demand governor 36 * cs_*: Conservative governor 37 */ 38 39 /* Governor demand based switching data (per-policy or global). */ 40 struct dbs_data { 41 struct gov_attr_set attr_set; 42 void *tuners; 43 unsigned int min_sampling_rate; 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 timer_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 /* 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_timer)(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, bool notify); 142 void (*exit)(struct dbs_data *dbs_data, bool notify); 143 void (*start)(struct cpufreq_policy *policy); 144 }; 145 146 static inline struct dbs_governor *dbs_governor_of(struct cpufreq_policy *policy) 147 { 148 return container_of(policy->governor, struct dbs_governor, gov); 149 } 150 151 /* Governor specific operations */ 152 struct od_ops { 153 unsigned int (*powersave_bias_target)(struct cpufreq_policy *policy, 154 unsigned int freq_next, unsigned int relation); 155 }; 156 157 unsigned int dbs_update(struct cpufreq_policy *policy); 158 int cpufreq_governor_dbs(struct cpufreq_policy *policy, unsigned int event); 159 void od_register_powersave_bias_handler(unsigned int (*f) 160 (struct cpufreq_policy *, unsigned int, unsigned int), 161 unsigned int powersave_bias); 162 void od_unregister_powersave_bias_handler(void); 163 ssize_t store_sampling_rate(struct gov_attr_set *attr_set, const char *buf, 164 size_t count); 165 void gov_update_cpu_data(struct dbs_data *dbs_data); 166 #endif /* _CPUFREQ_GOVERNOR_H */ 167