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