1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * governor.h - internal header for devfreq governors.
4 *
5 * Copyright (C) 2011 Samsung Electronics
6 * MyungJoo Ham <myungjoo.ham@samsung.com>
7 *
8 * This header is for devfreq governors in drivers/devfreq/
9 */
10
11 #ifndef _GOVERNOR_H
12 #define _GOVERNOR_H
13
14 #include <linux/devfreq.h>
15
16 #define DEVFREQ_NAME_LEN 16
17
18 #define to_devfreq(DEV) container_of((DEV), struct devfreq, dev)
19
20 /* Devfreq events */
21 #define DEVFREQ_GOV_START 0x1
22 #define DEVFREQ_GOV_STOP 0x2
23 #define DEVFREQ_GOV_UPDATE_INTERVAL 0x3
24 #define DEVFREQ_GOV_SUSPEND 0x4
25 #define DEVFREQ_GOV_RESUME 0x5
26
27 #define DEVFREQ_MIN_FREQ 0
28 #define DEVFREQ_MAX_FREQ ULONG_MAX
29
30 /*
31 * Definition of the governor feature flags
32 * - DEVFREQ_GOV_FLAG_IMMUTABLE
33 * : This governor is never changeable to other governors.
34 * - DEVFREQ_GOV_FLAG_IRQ_DRIVEN
35 * : The devfreq won't schedule the work for this governor.
36 */
37 #define DEVFREQ_GOV_FLAG_IMMUTABLE BIT(0)
38 #define DEVFREQ_GOV_FLAG_IRQ_DRIVEN BIT(1)
39
40 /*
41 * Definition of governor attribute flags except for common sysfs attributes
42 * - DEVFREQ_GOV_ATTR_POLLING_INTERVAL
43 * : Indicate polling_interval sysfs attribute
44 * - DEVFREQ_GOV_ATTR_TIMER
45 * : Indicate timer sysfs attribute
46 */
47 #define DEVFREQ_GOV_ATTR_POLLING_INTERVAL BIT(0)
48 #define DEVFREQ_GOV_ATTR_TIMER BIT(1)
49
50 /**
51 * struct devfreq_cpu_data - Hold the per-cpu data
52 * @node: list node
53 * @dev: reference to cpu device.
54 * @first_cpu: the cpumask of the first cpu of a policy.
55 * @opp_table: reference to cpu opp table.
56 * @cur_freq: the current frequency of the cpu.
57 * @min_freq: the min frequency of the cpu.
58 * @max_freq: the max frequency of the cpu.
59 *
60 * This structure stores the required cpu_data of a cpu.
61 * This is auto-populated by the governor.
62 */
63 struct devfreq_cpu_data {
64 struct list_head node;
65
66 struct device *dev;
67 unsigned int first_cpu;
68
69 struct opp_table *opp_table;
70 unsigned int cur_freq;
71 unsigned int min_freq;
72 unsigned int max_freq;
73 };
74
75 /**
76 * struct devfreq_governor - Devfreq policy governor
77 * @node: list node - contains registered devfreq governors
78 * @name: Governor's name
79 * @attrs: Governor's sysfs attribute flags
80 * @flags: Governor's feature flags
81 * @get_target_freq: Returns desired operating frequency for the device.
82 * Basically, get_target_freq will run
83 * devfreq_dev_profile.get_dev_status() to get the
84 * status of the device (load = busy_time / total_time).
85 * @event_handler: Callback for devfreq core framework to notify events
86 * to governors. Events include per device governor
87 * init and exit, opp changes out of devfreq, suspend
88 * and resume of per device devfreq during device idle.
89 *
90 * Note that the callbacks are called with devfreq->lock locked by devfreq.
91 */
92 struct devfreq_governor {
93 struct list_head node;
94
95 const char name[DEVFREQ_NAME_LEN];
96 const u64 attrs;
97 const u64 flags;
98 int (*get_target_freq)(struct devfreq *this, unsigned long *freq);
99 int (*event_handler)(struct devfreq *devfreq,
100 unsigned int event, void *data);
101 };
102
103 void devfreq_monitor_start(struct devfreq *devfreq);
104 void devfreq_monitor_stop(struct devfreq *devfreq);
105 void devfreq_monitor_suspend(struct devfreq *devfreq);
106 void devfreq_monitor_resume(struct devfreq *devfreq);
107 void devfreq_update_interval(struct devfreq *devfreq, unsigned int *delay);
108
109 int devfreq_add_governor(struct devfreq_governor *governor);
110 int devfreq_remove_governor(struct devfreq_governor *governor);
111
112 int devm_devfreq_add_governor(struct device *dev,
113 struct devfreq_governor *governor);
114
115 int devfreq_update_status(struct devfreq *devfreq, unsigned long freq);
116 int devfreq_update_target(struct devfreq *devfreq, unsigned long freq);
117 void devfreq_get_freq_range(struct devfreq *devfreq, unsigned long *min_freq,
118 unsigned long *max_freq);
119
devfreq_update_stats(struct devfreq * df)120 static inline int devfreq_update_stats(struct devfreq *df)
121 {
122 if (!df->profile->get_dev_status)
123 return -EINVAL;
124
125 return df->profile->get_dev_status(df->dev.parent, &df->last_status);
126 }
127 #endif /* _GOVERNOR_H */
128