1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * powercap.h: Data types and headers for sysfs power capping interface
4 * Copyright (c) 2013, Intel Corporation.
5 */
6
7#ifndef __POWERCAP_H__
8#define __POWERCAP_H__
9
10#include <linux/device.h>
11#include <linux/idr.h>
12
13/*
14 * A power cap class device can contain multiple powercap control_types.
15 * Each control_type can have multiple power zones, which can be independently
16 * controlled. Each power zone can have one or more constraints.
17 */
18
19struct powercap_control_type;
20struct powercap_zone;
21struct powercap_zone_constraint;
22
23/**
24 * struct powercap_control_type_ops - Define control type callbacks
25 * @set_enable: Enable/Disable whole control type.
26 * Default is enabled. But this callback allows all zones
27 * to be in disable state and remove any applied power
28 * limits. If disabled power zone can only be monitored
29 * not controlled.
30 * @get_enable: get Enable/Disable status.
31 * @release: Callback to inform that last reference to this
32 * control type is closed. So it is safe to free data
33 * structure associated with this control type.
34 * This callback is mandatory if the client own memory
35 * for the control type.
36 *
37 * This structure defines control type callbacks to be implemented by client
38 * drivers
39 */
40struct powercap_control_type_ops {
41 int (*set_enable) (struct powercap_control_type *, bool mode);
42 int (*get_enable) (struct powercap_control_type *, bool *mode);
43 int (*release) (struct powercap_control_type *);
44};
45
46/**
47 * struct powercap_control_type - Defines a powercap control_type
48 * @dev: device for this control_type
49 * @idr: idr to have unique id for its child
50 * @nr_zones: counter for number of zones of this type
51 * @ops: Pointer to callback struct
52 * @lock: mutex for control type
53 * @allocated: This is possible that client owns the memory
54 * used by this structure. In this case
55 * this flag is set to false by framework to
56 * prevent deallocation during release process.
57 * Otherwise this flag is set to true.
58 * @node: linked-list node
59 *
60 * Defines powercap control_type. This acts as a container for power
61 * zones, which use same method to control power. E.g. RAPL, RAPL-PCI etc.
62 * All fields are private and should not be used by client drivers.
63 */
64struct powercap_control_type {
65 struct device dev;
66 struct idr idr;
67 int nr_zones;
68 const struct powercap_control_type_ops *ops;
69 struct mutex lock;
70 bool allocated;
71 struct list_head node;
72};
73
74/**
75 * struct powercap_zone_ops - Define power zone callbacks
76 * @get_max_energy_range_uj: Get maximum range of energy counter in
77 * micro-joules.
78 * @get_energy_uj: Get current energy counter in micro-joules.
79 * @reset_energy_uj: Reset micro-joules energy counter.
80 * @get_max_power_range_uw: Get maximum range of power counter in
81 * micro-watts.
82 * @get_power_uw: Get current power counter in micro-watts.
83 * @set_enable: Enable/Disable power zone controls.
84 * Default is enabled.
85 * @get_enable: get Enable/Disable status.
86 * @release: Callback to inform that last reference to this
87 * control type is closed. So it is safe to free
88 * data structure associated with this
89 * control type. Mandatory, if client driver owns
90 * the power_zone memory.
91 *
92 * This structure defines zone callbacks to be implemented by client drivers.
93 * Client drives can define both energy and power related callbacks. But at
94 * the least one type (either power or energy) is mandatory. Client drivers
95 * should handle mutual exclusion, if required in callbacks.
96 */
97struct powercap_zone_ops {
98 int (*get_max_energy_range_uj) (struct powercap_zone *, u64 *);
99 int (*get_energy_uj) (struct powercap_zone *, u64 *);
100 int (*reset_energy_uj) (struct powercap_zone *);
101 int (*get_max_power_range_uw) (struct powercap_zone *, u64 *);
102 int (*get_power_uw) (struct powercap_zone *, u64 *);
103 int (*set_enable) (struct powercap_zone *, bool mode);
104 int (*get_enable) (struct powercap_zone *, bool *mode);
105 int (*release) (struct powercap_zone *);
106};
107
108#define POWERCAP_ZONE_MAX_ATTRS 6
109#define POWERCAP_CONSTRAINTS_ATTRS 8
110#define MAX_CONSTRAINTS_PER_ZONE 10
111/**
112 * struct powercap_zone- Defines instance of a power cap zone
113 * @id: Unique id
114 * @name: Power zone name.
115 * @control_type_inst: Control type instance for this zone.
116 * @ops: Pointer to the zone operation structure.
117 * @dev: Instance of a device.
118 * @const_id_cnt: Number of constraint defined.
119 * @idr: Instance to an idr entry for children zones.
120 * @parent_idr: To remove reference from the parent idr.
121 * @private_data: Private data pointer if any for this zone.
122 * @zone_dev_attrs: Attributes associated with this device.
123 * @zone_attr_count: Attribute count.
124 * @dev_zone_attr_group: Attribute group for attributes.
125 * @dev_attr_groups: Attribute group store to register with device.
126 * @allocated: This is possible that client owns the memory
127 * used by this structure. In this case
128 * this flag is set to false by framework to
129 * prevent deallocation during release process.
130 * Otherwise this flag is set to true.
131 * @constraints: List of constraints for this zone.
132 *
133 * This defines a power zone instance. The fields of this structure are
134 * private, and should not be used by client drivers.
135 */
136struct powercap_zone {
137 int id;
138 char *name;
139 void *control_type_inst;
140 const struct powercap_zone_ops *ops;
141 struct device dev;
142 int const_id_cnt;
143 struct idr idr;
144 struct idr *parent_idr;
145 void *private_data;
146 struct attribute **zone_dev_attrs;
147 int zone_attr_count;
148 struct attribute_group dev_zone_attr_group;
149 const struct attribute_group *dev_attr_groups[2]; /* 1 group + NULL */
150 bool allocated;
151 struct powercap_zone_constraint *constraints;
152};
153
154/**
155 * struct powercap_zone_constraint_ops - Define constraint callbacks
156 * @set_power_limit_uw: Set power limit in micro-watts.
157 * @get_power_limit_uw: Get power limit in micro-watts.
158 * @set_time_window_us: Set time window in micro-seconds.
159 * @get_time_window_us: Get time window in micro-seconds.
160 * @get_max_power_uw: Get max power allowed in micro-watts.
161 * @get_min_power_uw: Get min power allowed in micro-watts.
162 * @get_max_time_window_us: Get max time window allowed in micro-seconds.
163 * @get_min_time_window_us: Get min time window allowed in micro-seconds.
164 * @get_name: Get the name of constraint
165 *
166 * This structure is used to define the constraint callbacks for the client
167 * drivers. The following callbacks are mandatory and can't be NULL:
168 * set_power_limit_uw
169 * get_power_limit_uw
170 * set_time_window_us
171 * get_time_window_us
172 * get_name
173 * Client drivers should handle mutual exclusion, if required in callbacks.
174 */
175struct powercap_zone_constraint_ops {
176 int (*set_power_limit_uw) (struct powercap_zone *, int, u64);
177 int (*get_power_limit_uw) (struct powercap_zone *, int, u64 *);
178 int (*set_time_window_us) (struct powercap_zone *, int, u64);
179 int (*get_time_window_us) (struct powercap_zone *, int, u64 *);
180 int (*get_max_power_uw) (struct powercap_zone *, int, u64 *);
181 int (*get_min_power_uw) (struct powercap_zone *, int, u64 *);
182 int (*get_max_time_window_us) (struct powercap_zone *, int, u64 *);
183 int (*get_min_time_window_us) (struct powercap_zone *, int, u64 *);
184 const char *(*get_name) (struct powercap_zone *, int);
185};
186
187/**
188 * struct powercap_zone_constraint- Defines instance of a constraint
189 * @id: Instance Id of this constraint.
190 * @power_zone: Pointer to the power zone for this constraint.
191 * @ops: Pointer to the constraint callbacks.
192 *
193 * This defines a constraint instance.
194 */
195struct powercap_zone_constraint {
196 int id;
197 struct powercap_zone *power_zone;
198 const struct powercap_zone_constraint_ops *ops;
199};
200
201
202/* For clients to get their device pointer, may be used for dev_dbgs */
203#define POWERCAP_GET_DEV(power_zone) (&power_zone->dev)
204
205/**
206* powercap_set_zone_data() - Set private data for a zone
207* @power_zone: A pointer to the valid zone instance.
208* @pdata: A pointer to the user private data.
209*
210* Allows client drivers to associate some private data to zone instance.
211*/
212static inline void powercap_set_zone_data(struct powercap_zone *power_zone,
213 void *pdata)
214{
215 if (power_zone)
216 power_zone->private_data = pdata;
217}
218
219/**
220* powercap_get_zone_data() - Get private data for a zone
221* @power_zone: A pointer to the valid zone instance.
222*
223* Allows client drivers to get private data associate with a zone,
224* using call to powercap_set_zone_data.
225*/
226static inline void *powercap_get_zone_data(struct powercap_zone *power_zone)
227{
228 if (power_zone)
229 return power_zone->private_data;
230 return NULL;
231}
232
233/**
234* powercap_register_control_type() - Register a control_type with framework
235* @control_type: Pointer to client allocated memory for the control type
236* structure storage. If this is NULL, powercap framework
237* will allocate memory and own it.
238* Advantage of this parameter is that client can embed
239* this data in its data structures and allocate in a
240* single call, preventing multiple allocations.
241* @control_type_name: The Name of this control_type, which will be shown
242* in the sysfs Interface.
243* @ops: Callbacks for control type. This parameter is optional.
244*
245* Used to create a control_type with the power capping class. Here control_type
246* can represent a type of technology, which can control a range of power zones.
247* For example a control_type can be RAPL (Running Average Power Limit)
248* Intel® 64 and IA-32 Processor Architectures. The name can be any string
249* which must be unique, otherwise this function returns NULL.
250* A pointer to the control_type instance is returned on success.
251*/
252struct powercap_control_type *powercap_register_control_type(
253 struct powercap_control_type *control_type,
254 const char *name,
255 const struct powercap_control_type_ops *ops);
256
257/**
258* powercap_unregister_control_type() - Unregister a control_type from framework
259* @instance: A pointer to the valid control_type instance.
260*
261* Used to unregister a control_type with the power capping class.
262* All power zones registered under this control type have to be unregistered
263* before calling this function, or it will fail with an error code.
264*/
265int powercap_unregister_control_type(struct powercap_control_type *instance);
266
267/* Zone register/unregister API */
268
269/**
270* powercap_register_zone() - Register a power zone
271* @power_zone: Pointer to client allocated memory for the power zone structure
272* storage. If this is NULL, powercap framework will allocate
273* memory and own it. Advantage of this parameter is that client
274* can embed this data in its data structures and allocate in a
275* single call, preventing multiple allocations.
276* @control_type: A control_type instance under which this zone operates.
277* @name: A name for this zone.
278* @parent: A pointer to the parent power zone instance if any or NULL
279* @ops: Pointer to zone operation callback structure.
280* @no_constraints: Number of constraints for this zone
281* @const_ops: Pointer to constraint callback structure
282*
283* Register a power zone under a given control type. A power zone must register
284* a pointer to a structure representing zone callbacks.
285* A power zone can be located under a parent power zone, in which case @parent
286* should point to it. Otherwise, if @parent is NULL, the new power zone will
287* be located directly under the given control type
288* For each power zone there may be a number of constraints that appear in the
289* sysfs under that zone as attributes with unique numeric IDs.
290* Returns pointer to the power_zone on success.
291*/
292struct powercap_zone *powercap_register_zone(
293 struct powercap_zone *power_zone,
294 struct powercap_control_type *control_type,
295 const char *name,
296 struct powercap_zone *parent,
297 const struct powercap_zone_ops *ops,
298 int nr_constraints,
299 const struct powercap_zone_constraint_ops *const_ops);
300
301/**
302* powercap_unregister_zone() - Unregister a zone device
303* @control_type: A pointer to the valid instance of a control_type.
304* @power_zone: A pointer to the valid zone instance for a control_type
305*
306* Used to unregister a zone device for a control_type. Caller should
307* make sure that children for this zone are unregistered first.
308*/
309int powercap_unregister_zone(struct powercap_control_type *control_type,
310 struct powercap_zone *power_zone);
311
312#endif
313

source code of linux/include/linux/powercap.h