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 | |