1/*
2 * powercap.h: Data types and headers for sysfs power capping interface
3 * Copyright (c) 2013, Intel Corporation.
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc.
16 *
17 */
18
19#ifndef __POWERCAP_H__
20#define __POWERCAP_H__
21
22#include <linux/device.h>
23#include <linux/idr.h>
24
25/*
26 * A power cap class device can contain multiple powercap control_types.
27 * Each control_type can have multiple power zones, which can be independently
28 * controlled. Each power zone can have one or more constraints.
29 */
30
31struct powercap_control_type;
32struct powercap_zone;
33struct powercap_zone_constraint;
34
35/**
36 * struct powercap_control_type_ops - Define control type callbacks
37 * @set_enable: Enable/Disable whole control type.
38 * Default is enabled. But this callback allows all zones
39 * to be in disable state and remove any applied power
40 * limits. If disabled power zone can only be monitored
41 * not controlled.
42 * @get_enable: get Enable/Disable status.
43 * @release: Callback to inform that last reference to this
44 * control type is closed. So it is safe to free data
45 * structure associated with this control type.
46 * This callback is mandatory if the client own memory
47 * for the control type.
48 *
49 * This structure defines control type callbacks to be implemented by client
50 * drivers
51 */
52struct powercap_control_type_ops {
53 int (*set_enable) (struct powercap_control_type *, bool mode);
54 int (*get_enable) (struct powercap_control_type *, bool *mode);
55 int (*release) (struct powercap_control_type *);
56};
57
58/**
59 * struct powercap_control_type- Defines a powercap control_type
60 * @name: name of control_type
61 * @dev: device for this control_type
62 * @idr: idr to have unique id for its child
63 * @root_node: Root holding power zones for this control_type
64 * @ops: Pointer to callback struct
65 * @node_lock: mutex for control type
66 * @allocated: This is possible that client owns the memory
67 * used by this structure. In this case
68 * this flag is set to false by framework to
69 * prevent deallocation during release process.
70 * Otherwise this flag is set to true.
71 * @ctrl_inst: link to the control_type list
72 *
73 * Defines powercap control_type. This acts as a container for power
74 * zones, which use same method to control power. E.g. RAPL, RAPL-PCI etc.
75 * All fields are private and should not be used by client drivers.
76 */
77struct powercap_control_type {
78 struct device dev;
79 struct idr idr;
80 int nr_zones;
81 const struct powercap_control_type_ops *ops;
82 struct mutex lock;
83 bool allocated;
84 struct list_head node;
85};
86
87/**
88 * struct powercap_zone_ops - Define power zone callbacks
89 * @get_max_energy_range_uj: Get maximum range of energy counter in
90 * micro-joules.
91 * @get_energy_uj: Get current energy counter in micro-joules.
92 * @reset_energy_uj: Reset micro-joules energy counter.
93 * @get_max_power_range_uw: Get maximum range of power counter in
94 * micro-watts.
95 * @get_power_uw: Get current power counter in micro-watts.
96 * @set_enable: Enable/Disable power zone controls.
97 * Default is enabled.
98 * @get_enable: get Enable/Disable status.
99 * @release: Callback to inform that last reference to this
100 * control type is closed. So it is safe to free
101 * data structure associated with this
102 * control type. Mandatory, if client driver owns
103 * the power_zone memory.
104 *
105 * This structure defines zone callbacks to be implemented by client drivers.
106 * Client drives can define both energy and power related callbacks. But at
107 * the least one type (either power or energy) is mandatory. Client drivers
108 * should handle mutual exclusion, if required in callbacks.
109 */
110struct powercap_zone_ops {
111 int (*get_max_energy_range_uj) (struct powercap_zone *, u64 *);
112 int (*get_energy_uj) (struct powercap_zone *, u64 *);
113 int (*reset_energy_uj) (struct powercap_zone *);
114 int (*get_max_power_range_uw) (struct powercap_zone *, u64 *);
115 int (*get_power_uw) (struct powercap_zone *, u64 *);
116 int (*set_enable) (struct powercap_zone *, bool mode);
117 int (*get_enable) (struct powercap_zone *, bool *mode);
118 int (*release) (struct powercap_zone *);
119};
120
121#define POWERCAP_ZONE_MAX_ATTRS 6
122#define POWERCAP_CONSTRAINTS_ATTRS 8
123#define MAX_CONSTRAINTS_PER_ZONE 10
124/**
125 * struct powercap_zone- Defines instance of a power cap zone
126 * @id: Unique id
127 * @name: Power zone name.
128 * @control_type_inst: Control type instance for this zone.
129 * @ops: Pointer to the zone operation structure.
130 * @dev: Instance of a device.
131 * @const_id_cnt: Number of constraint defined.
132 * @idr: Instance to an idr entry for children zones.
133 * @parent_idr: To remove reference from the parent idr.
134 * @private_data: Private data pointer if any for this zone.
135 * @zone_dev_attrs: Attributes associated with this device.
136 * @zone_attr_count: Attribute count.
137 * @dev_zone_attr_group: Attribute group for attributes.
138 * @dev_attr_groups: Attribute group store to register with device.
139 * @allocated: This is possible that client owns the memory
140 * used by this structure. In this case
141 * this flag is set to false by framework to
142 * prevent deallocation during release process.
143 * Otherwise this flag is set to true.
144 * @constraint_ptr: List of constraints for this zone.
145 *
146 * This defines a power zone instance. The fields of this structure are
147 * private, and should not be used by client drivers.
148 */
149struct powercap_zone {
150 int id;
151 char *name;
152 void *control_type_inst;
153 const struct powercap_zone_ops *ops;
154 struct device dev;
155 int const_id_cnt;
156 struct idr idr;
157 struct idr *parent_idr;
158 void *private_data;
159 struct attribute **zone_dev_attrs;
160 int zone_attr_count;
161 struct attribute_group dev_zone_attr_group;
162 const struct attribute_group *dev_attr_groups[2]; /* 1 group + NULL */
163 bool allocated;
164 struct powercap_zone_constraint *constraints;
165};
166
167/**
168 * struct powercap_zone_constraint_ops - Define constraint callbacks
169 * @set_power_limit_uw: Set power limit in micro-watts.
170 * @get_power_limit_uw: Get power limit in micro-watts.
171 * @set_time_window_us: Set time window in micro-seconds.
172 * @get_time_window_us: Get time window in micro-seconds.
173 * @get_max_power_uw: Get max power allowed in micro-watts.
174 * @get_min_power_uw: Get min power allowed in micro-watts.
175 * @get_max_time_window_us: Get max time window allowed in micro-seconds.
176 * @get_min_time_window_us: Get min time window allowed in micro-seconds.
177 * @get_name: Get the name of constraint
178 *
179 * This structure is used to define the constraint callbacks for the client
180 * drivers. The following callbacks are mandatory and can't be NULL:
181 * set_power_limit_uw
182 * get_power_limit_uw
183 * set_time_window_us
184 * get_time_window_us
185 * get_name
186 * Client drivers should handle mutual exclusion, if required in callbacks.
187 */
188struct powercap_zone_constraint_ops {
189 int (*set_power_limit_uw) (struct powercap_zone *, int, u64);
190 int (*get_power_limit_uw) (struct powercap_zone *, int, u64 *);
191 int (*set_time_window_us) (struct powercap_zone *, int, u64);
192 int (*get_time_window_us) (struct powercap_zone *, int, u64 *);
193 int (*get_max_power_uw) (struct powercap_zone *, int, u64 *);
194 int (*get_min_power_uw) (struct powercap_zone *, int, u64 *);
195 int (*get_max_time_window_us) (struct powercap_zone *, int, u64 *);
196 int (*get_min_time_window_us) (struct powercap_zone *, int, u64 *);
197 const char *(*get_name) (struct powercap_zone *, int);
198};
199
200/**
201 * struct powercap_zone_constraint- Defines instance of a constraint
202 * @id: Instance Id of this constraint.
203 * @power_zone: Pointer to the power zone for this constraint.
204 * @ops: Pointer to the constraint callbacks.
205 *
206 * This defines a constraint instance.
207 */
208struct powercap_zone_constraint {
209 int id;
210 struct powercap_zone *power_zone;
211 const struct powercap_zone_constraint_ops *ops;
212};
213
214
215/* For clients to get their device pointer, may be used for dev_dbgs */
216#define POWERCAP_GET_DEV(power_zone) (&power_zone->dev)
217
218/**
219* powercap_set_zone_data() - Set private data for a zone
220* @power_zone: A pointer to the valid zone instance.
221* @pdata: A pointer to the user private data.
222*
223* Allows client drivers to associate some private data to zone instance.
224*/
225static inline void powercap_set_zone_data(struct powercap_zone *power_zone,
226 void *pdata)
227{
228 if (power_zone)
229 power_zone->private_data = pdata;
230}
231
232/**
233* powercap_get_zone_data() - Get private data for a zone
234* @power_zone: A pointer to the valid zone instance.
235*
236* Allows client drivers to get private data associate with a zone,
237* using call to powercap_set_zone_data.
238*/
239static inline void *powercap_get_zone_data(struct powercap_zone *power_zone)
240{
241 if (power_zone)
242 return power_zone->private_data;
243 return NULL;
244}
245
246/**
247* powercap_register_control_type() - Register a control_type with framework
248* @control_type: Pointer to client allocated memory for the control type
249* structure storage. If this is NULL, powercap framework
250* will allocate memory and own it.
251* Advantage of this parameter is that client can embed
252* this data in its data structures and allocate in a
253* single call, preventing multiple allocations.
254* @control_type_name: The Name of this control_type, which will be shown
255* in the sysfs Interface.
256* @ops: Callbacks for control type. This parameter is optional.
257*
258* Used to create a control_type with the power capping class. Here control_type
259* can represent a type of technology, which can control a range of power zones.
260* For example a control_type can be RAPL (Running Average Power Limit)
261* IntelĀ® 64 and IA-32 Processor Architectures. The name can be any string
262* which must be unique, otherwise this function returns NULL.
263* A pointer to the control_type instance is returned on success.
264*/
265struct powercap_control_type *powercap_register_control_type(
266 struct powercap_control_type *control_type,
267 const char *name,
268 const struct powercap_control_type_ops *ops);
269
270/**
271* powercap_unregister_control_type() - Unregister a control_type from framework
272* @instance: A pointer to the valid control_type instance.
273*
274* Used to unregister a control_type with the power capping class.
275* All power zones registered under this control type have to be unregistered
276* before calling this function, or it will fail with an error code.
277*/
278int powercap_unregister_control_type(struct powercap_control_type *instance);
279
280/* Zone register/unregister API */
281
282/**
283* powercap_register_zone() - Register a power zone
284* @power_zone: Pointer to client allocated memory for the power zone structure
285* storage. If this is NULL, powercap framework will allocate
286* memory and own it. Advantage of this parameter is that client
287* can embed this data in its data structures and allocate in a
288* single call, preventing multiple allocations.
289* @control_type: A control_type instance under which this zone operates.
290* @name: A name for this zone.
291* @parent: A pointer to the parent power zone instance if any or NULL
292* @ops: Pointer to zone operation callback structure.
293* @no_constraints: Number of constraints for this zone
294* @const_ops: Pointer to constraint callback structure
295*
296* Register a power zone under a given control type. A power zone must register
297* a pointer to a structure representing zone callbacks.
298* A power zone can be located under a parent power zone, in which case @parent
299* should point to it. Otherwise, if @parent is NULL, the new power zone will
300* be located directly under the given control type
301* For each power zone there may be a number of constraints that appear in the
302* sysfs under that zone as attributes with unique numeric IDs.
303* Returns pointer to the power_zone on success.
304*/
305struct powercap_zone *powercap_register_zone(
306 struct powercap_zone *power_zone,
307 struct powercap_control_type *control_type,
308 const char *name,
309 struct powercap_zone *parent,
310 const struct powercap_zone_ops *ops,
311 int nr_constraints,
312 const struct powercap_zone_constraint_ops *const_ops);
313
314/**
315* powercap_unregister_zone() - Unregister a zone device
316* @control_type: A pointer to the valid instance of a control_type.
317* @power_zone: A pointer to the valid zone instance for a control_type
318*
319* Used to unregister a zone device for a control_type. Caller should
320* make sure that children for this zone are unregistered first.
321*/
322int powercap_unregister_zone(struct powercap_control_type *control_type,
323 struct powercap_zone *power_zone);
324
325#endif
326