xref: /openbmc/linux/include/linux/thermal.h (revision 965f22bc)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  thermal.h  ($Revision: 0 $)
4  *
5  *  Copyright (C) 2008  Intel Corp
6  *  Copyright (C) 2008  Zhang Rui <rui.zhang@intel.com>
7  *  Copyright (C) 2008  Sujith Thomas <sujith.thomas@intel.com>
8  */
9 
10 #ifndef __THERMAL_H__
11 #define __THERMAL_H__
12 
13 #include <linux/of.h>
14 #include <linux/idr.h>
15 #include <linux/device.h>
16 #include <linux/sysfs.h>
17 #include <linux/workqueue.h>
18 #include <uapi/linux/thermal.h>
19 
20 #define THERMAL_TRIPS_NONE	-1
21 #define THERMAL_MAX_TRIPS	12
22 
23 /* invalid cooling state */
24 #define THERMAL_CSTATE_INVALID -1UL
25 
26 /* No upper/lower limit requirement */
27 #define THERMAL_NO_LIMIT	((u32)~0)
28 
29 /* Default weight of a bound cooling device */
30 #define THERMAL_WEIGHT_DEFAULT 0
31 
32 /* use value, which < 0K, to indicate an invalid/uninitialized temperature */
33 #define THERMAL_TEMP_INVALID	-274000
34 
35 /* Unit conversion macros */
36 #define DECI_KELVIN_TO_CELSIUS(t)	({			\
37 	long _t = (t);						\
38 	((_t-2732 >= 0) ? (_t-2732+5)/10 : (_t-2732-5)/10);	\
39 })
40 #define CELSIUS_TO_DECI_KELVIN(t)	((t)*10+2732)
41 #define DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(t, off) (((t) - (off)) * 100)
42 #define DECI_KELVIN_TO_MILLICELSIUS(t) DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(t, 2732)
43 #define MILLICELSIUS_TO_DECI_KELVIN_WITH_OFFSET(t, off) (((t) / 100) + (off))
44 #define MILLICELSIUS_TO_DECI_KELVIN(t) MILLICELSIUS_TO_DECI_KELVIN_WITH_OFFSET(t, 2732)
45 
46 /* Default Thermal Governor */
47 #if defined(CONFIG_THERMAL_DEFAULT_GOV_STEP_WISE)
48 #define DEFAULT_THERMAL_GOVERNOR       "step_wise"
49 #elif defined(CONFIG_THERMAL_DEFAULT_GOV_FAIR_SHARE)
50 #define DEFAULT_THERMAL_GOVERNOR       "fair_share"
51 #elif defined(CONFIG_THERMAL_DEFAULT_GOV_USER_SPACE)
52 #define DEFAULT_THERMAL_GOVERNOR       "user_space"
53 #elif defined(CONFIG_THERMAL_DEFAULT_GOV_POWER_ALLOCATOR)
54 #define DEFAULT_THERMAL_GOVERNOR       "power_allocator"
55 #endif
56 
57 struct thermal_zone_device;
58 struct thermal_cooling_device;
59 struct thermal_instance;
60 
61 enum thermal_device_mode {
62 	THERMAL_DEVICE_DISABLED = 0,
63 	THERMAL_DEVICE_ENABLED,
64 };
65 
66 enum thermal_trip_type {
67 	THERMAL_TRIP_ACTIVE = 0,
68 	THERMAL_TRIP_PASSIVE,
69 	THERMAL_TRIP_HOT,
70 	THERMAL_TRIP_CRITICAL,
71 };
72 
73 enum thermal_trend {
74 	THERMAL_TREND_STABLE, /* temperature is stable */
75 	THERMAL_TREND_RAISING, /* temperature is raising */
76 	THERMAL_TREND_DROPPING, /* temperature is dropping */
77 	THERMAL_TREND_RAISE_FULL, /* apply highest cooling action */
78 	THERMAL_TREND_DROP_FULL, /* apply lowest cooling action */
79 };
80 
81 /* Thermal notification reason */
82 enum thermal_notify_event {
83 	THERMAL_EVENT_UNSPECIFIED, /* Unspecified event */
84 	THERMAL_EVENT_TEMP_SAMPLE, /* New Temperature sample */
85 	THERMAL_TRIP_VIOLATED, /* TRIP Point violation */
86 	THERMAL_TRIP_CHANGED, /* TRIP Point temperature changed */
87 	THERMAL_DEVICE_DOWN, /* Thermal device is down */
88 	THERMAL_DEVICE_UP, /* Thermal device is up after a down event */
89 	THERMAL_DEVICE_POWER_CAPABILITY_CHANGED, /* power capability changed */
90 	THERMAL_TABLE_CHANGED, /* Thermal table(s) changed */
91 };
92 
93 struct thermal_zone_device_ops {
94 	int (*bind) (struct thermal_zone_device *,
95 		     struct thermal_cooling_device *);
96 	int (*unbind) (struct thermal_zone_device *,
97 		       struct thermal_cooling_device *);
98 	int (*get_temp) (struct thermal_zone_device *, int *);
99 	int (*set_trips) (struct thermal_zone_device *, int, int);
100 	int (*get_mode) (struct thermal_zone_device *,
101 			 enum thermal_device_mode *);
102 	int (*set_mode) (struct thermal_zone_device *,
103 		enum thermal_device_mode);
104 	int (*get_trip_type) (struct thermal_zone_device *, int,
105 		enum thermal_trip_type *);
106 	int (*get_trip_temp) (struct thermal_zone_device *, int, int *);
107 	int (*set_trip_temp) (struct thermal_zone_device *, int, int);
108 	int (*get_trip_hyst) (struct thermal_zone_device *, int, int *);
109 	int (*set_trip_hyst) (struct thermal_zone_device *, int, int);
110 	int (*get_crit_temp) (struct thermal_zone_device *, int *);
111 	int (*set_emul_temp) (struct thermal_zone_device *, int);
112 	int (*get_trend) (struct thermal_zone_device *, int,
113 			  enum thermal_trend *);
114 	int (*notify) (struct thermal_zone_device *, int,
115 		       enum thermal_trip_type);
116 };
117 
118 struct thermal_cooling_device_ops {
119 	int (*get_max_state) (struct thermal_cooling_device *, unsigned long *);
120 	int (*get_cur_state) (struct thermal_cooling_device *, unsigned long *);
121 	int (*set_cur_state) (struct thermal_cooling_device *, unsigned long);
122 	int (*get_requested_power)(struct thermal_cooling_device *,
123 				   struct thermal_zone_device *, u32 *);
124 	int (*state2power)(struct thermal_cooling_device *,
125 			   struct thermal_zone_device *, unsigned long, u32 *);
126 	int (*power2state)(struct thermal_cooling_device *,
127 			   struct thermal_zone_device *, u32, unsigned long *);
128 };
129 
130 struct thermal_cooling_device {
131 	int id;
132 	char type[THERMAL_NAME_LENGTH];
133 	struct device device;
134 	struct device_node *np;
135 	void *devdata;
136 	void *stats;
137 	const struct thermal_cooling_device_ops *ops;
138 	bool updated; /* true if the cooling device does not need update */
139 	struct mutex lock; /* protect thermal_instances list */
140 	struct list_head thermal_instances;
141 	struct list_head node;
142 };
143 
144 struct thermal_attr {
145 	struct device_attribute attr;
146 	char name[THERMAL_NAME_LENGTH];
147 };
148 
149 /**
150  * struct thermal_zone_device - structure for a thermal zone
151  * @id:		unique id number for each thermal zone
152  * @type:	the thermal zone device type
153  * @device:	&struct device for this thermal zone
154  * @trip_temp_attrs:	attributes for trip points for sysfs: trip temperature
155  * @trip_type_attrs:	attributes for trip points for sysfs: trip type
156  * @trip_hyst_attrs:	attributes for trip points for sysfs: trip hysteresis
157  * @devdata:	private pointer for device private data
158  * @trips:	number of trip points the thermal zone supports
159  * @trips_disabled;	bitmap for disabled trips
160  * @passive_delay:	number of milliseconds to wait between polls when
161  *			performing passive cooling.
162  * @polling_delay:	number of milliseconds to wait between polls when
163  *			checking whether trip points have been crossed (0 for
164  *			interrupt driven systems)
165  * @temperature:	current temperature.  This is only for core code,
166  *			drivers should use thermal_zone_get_temp() to get the
167  *			current temperature
168  * @last_temperature:	previous temperature read
169  * @emul_temperature:	emulated temperature when using CONFIG_THERMAL_EMULATION
170  * @passive:		1 if you've crossed a passive trip point, 0 otherwise.
171  * @prev_low_trip:	the low current temperature if you've crossed a passive
172 			trip point.
173  * @prev_high_trip:	the above current temperature if you've crossed a
174 			passive trip point.
175  * @forced_passive:	If > 0, temperature at which to switch on all ACPI
176  *			processor cooling devices.  Currently only used by the
177  *			step-wise governor.
178  * @need_update:	if equals 1, thermal_zone_device_update needs to be invoked.
179  * @ops:	operations this &thermal_zone_device supports
180  * @tzp:	thermal zone parameters
181  * @governor:	pointer to the governor for this thermal zone
182  * @governor_data:	private pointer for governor data
183  * @thermal_instances:	list of &struct thermal_instance of this thermal zone
184  * @ida:	&struct ida to generate unique id for this zone's cooling
185  *		devices
186  * @lock:	lock to protect thermal_instances list
187  * @node:	node in thermal_tz_list (in thermal_core.c)
188  * @poll_queue:	delayed work for polling
189  * @notify_event: Last notification event
190  */
191 struct thermal_zone_device {
192 	int id;
193 	char type[THERMAL_NAME_LENGTH];
194 	struct device device;
195 	struct attribute_group trips_attribute_group;
196 	struct thermal_attr *trip_temp_attrs;
197 	struct thermal_attr *trip_type_attrs;
198 	struct thermal_attr *trip_hyst_attrs;
199 	void *devdata;
200 	int trips;
201 	unsigned long trips_disabled;	/* bitmap for disabled trips */
202 	int passive_delay;
203 	int polling_delay;
204 	int temperature;
205 	int last_temperature;
206 	int emul_temperature;
207 	int passive;
208 	int prev_low_trip;
209 	int prev_high_trip;
210 	unsigned int forced_passive;
211 	atomic_t need_update;
212 	struct thermal_zone_device_ops *ops;
213 	struct thermal_zone_params *tzp;
214 	struct thermal_governor *governor;
215 	void *governor_data;
216 	struct list_head thermal_instances;
217 	struct ida ida;
218 	struct mutex lock;
219 	struct list_head node;
220 	struct delayed_work poll_queue;
221 	enum thermal_notify_event notify_event;
222 };
223 
224 /**
225  * struct thermal_governor - structure that holds thermal governor information
226  * @name:	name of the governor
227  * @bind_to_tz: callback called when binding to a thermal zone.  If it
228  *		returns 0, the governor is bound to the thermal zone,
229  *		otherwise it fails.
230  * @unbind_from_tz:	callback called when a governor is unbound from a
231  *			thermal zone.
232  * @throttle:	callback called for every trip point even if temperature is
233  *		below the trip point temperature
234  * @governor_list:	node in thermal_governor_list (in thermal_core.c)
235  */
236 struct thermal_governor {
237 	char name[THERMAL_NAME_LENGTH];
238 	int (*bind_to_tz)(struct thermal_zone_device *tz);
239 	void (*unbind_from_tz)(struct thermal_zone_device *tz);
240 	int (*throttle)(struct thermal_zone_device *tz, int trip);
241 	struct list_head	governor_list;
242 };
243 
244 /* Structure that holds binding parameters for a zone */
245 struct thermal_bind_params {
246 	struct thermal_cooling_device *cdev;
247 
248 	/*
249 	 * This is a measure of 'how effectively these devices can
250 	 * cool 'this' thermal zone. It shall be determined by
251 	 * platform characterization. This value is relative to the
252 	 * rest of the weights so a cooling device whose weight is
253 	 * double that of another cooling device is twice as
254 	 * effective. See Documentation/thermal/sysfs-api.txt for more
255 	 * information.
256 	 */
257 	int weight;
258 
259 	/*
260 	 * This is a bit mask that gives the binding relation between this
261 	 * thermal zone and cdev, for a particular trip point.
262 	 * See Documentation/thermal/sysfs-api.txt for more information.
263 	 */
264 	int trip_mask;
265 
266 	/*
267 	 * This is an array of cooling state limits. Must have exactly
268 	 * 2 * thermal_zone.number_of_trip_points. It is an array consisting
269 	 * of tuples <lower-state upper-state> of state limits. Each trip
270 	 * will be associated with one state limit tuple when binding.
271 	 * A NULL pointer means <THERMAL_NO_LIMITS THERMAL_NO_LIMITS>
272 	 * on all trips.
273 	 */
274 	unsigned long *binding_limits;
275 	int (*match) (struct thermal_zone_device *tz,
276 			struct thermal_cooling_device *cdev);
277 };
278 
279 /* Structure to define Thermal Zone parameters */
280 struct thermal_zone_params {
281 	char governor_name[THERMAL_NAME_LENGTH];
282 
283 	/*
284 	 * a boolean to indicate if the thermal to hwmon sysfs interface
285 	 * is required. when no_hwmon == false, a hwmon sysfs interface
286 	 * will be created. when no_hwmon == true, nothing will be done
287 	 */
288 	bool no_hwmon;
289 
290 	int num_tbps;	/* Number of tbp entries */
291 	struct thermal_bind_params *tbp;
292 
293 	/*
294 	 * Sustainable power (heat) that this thermal zone can dissipate in
295 	 * mW
296 	 */
297 	u32 sustainable_power;
298 
299 	/*
300 	 * Proportional parameter of the PID controller when
301 	 * overshooting (i.e., when temperature is below the target)
302 	 */
303 	s32 k_po;
304 
305 	/*
306 	 * Proportional parameter of the PID controller when
307 	 * undershooting
308 	 */
309 	s32 k_pu;
310 
311 	/* Integral parameter of the PID controller */
312 	s32 k_i;
313 
314 	/* Derivative parameter of the PID controller */
315 	s32 k_d;
316 
317 	/* threshold below which the error is no longer accumulated */
318 	s32 integral_cutoff;
319 
320 	/*
321 	 * @slope:	slope of a linear temperature adjustment curve.
322 	 * 		Used by thermal zone drivers.
323 	 */
324 	int slope;
325 	/*
326 	 * @offset:	offset of a linear temperature adjustment curve.
327 	 * 		Used by thermal zone drivers (default 0).
328 	 */
329 	int offset;
330 };
331 
332 struct thermal_genl_event {
333 	u32 orig;
334 	enum events event;
335 };
336 
337 /**
338  * struct thermal_zone_of_device_ops - scallbacks for handling DT based zones
339  *
340  * Mandatory:
341  * @get_temp: a pointer to a function that reads the sensor temperature.
342  *
343  * Optional:
344  * @get_trend: a pointer to a function that reads the sensor temperature trend.
345  * @set_trips: a pointer to a function that sets a temperature window. When
346  *	       this window is left the driver must inform the thermal core via
347  *	       thermal_zone_device_update.
348  * @set_emul_temp: a pointer to a function that sets sensor emulated
349  *		   temperature.
350  * @set_trip_temp: a pointer to a function that sets the trip temperature on
351  *		   hardware.
352  */
353 struct thermal_zone_of_device_ops {
354 	int (*get_temp)(void *, int *);
355 	int (*get_trend)(void *, int, enum thermal_trend *);
356 	int (*set_trips)(void *, int, int);
357 	int (*set_emul_temp)(void *, int);
358 	int (*set_trip_temp)(void *, int, int);
359 };
360 
361 /**
362  * struct thermal_trip - representation of a point in temperature domain
363  * @np: pointer to struct device_node that this trip point was created from
364  * @temperature: temperature value in miliCelsius
365  * @hysteresis: relative hysteresis in miliCelsius
366  * @type: trip point type
367  */
368 
369 struct thermal_trip {
370 	struct device_node *np;
371 	int temperature;
372 	int hysteresis;
373 	enum thermal_trip_type type;
374 };
375 
376 /* Function declarations */
377 #ifdef CONFIG_THERMAL_OF
378 struct thermal_zone_device *
379 thermal_zone_of_sensor_register(struct device *dev, int id, void *data,
380 				const struct thermal_zone_of_device_ops *ops);
381 void thermal_zone_of_sensor_unregister(struct device *dev,
382 				       struct thermal_zone_device *tz);
383 struct thermal_zone_device *devm_thermal_zone_of_sensor_register(
384 		struct device *dev, int id, void *data,
385 		const struct thermal_zone_of_device_ops *ops);
386 void devm_thermal_zone_of_sensor_unregister(struct device *dev,
387 					    struct thermal_zone_device *tz);
388 #else
389 static inline struct thermal_zone_device *
390 thermal_zone_of_sensor_register(struct device *dev, int id, void *data,
391 				const struct thermal_zone_of_device_ops *ops)
392 {
393 	return ERR_PTR(-ENODEV);
394 }
395 
396 static inline
397 void thermal_zone_of_sensor_unregister(struct device *dev,
398 				       struct thermal_zone_device *tz)
399 {
400 }
401 
402 static inline struct thermal_zone_device *devm_thermal_zone_of_sensor_register(
403 		struct device *dev, int id, void *data,
404 		const struct thermal_zone_of_device_ops *ops)
405 {
406 	return ERR_PTR(-ENODEV);
407 }
408 
409 static inline
410 void devm_thermal_zone_of_sensor_unregister(struct device *dev,
411 					    struct thermal_zone_device *tz)
412 {
413 }
414 
415 #endif
416 
417 #if IS_ENABLED(CONFIG_THERMAL)
418 static inline bool cdev_is_power_actor(struct thermal_cooling_device *cdev)
419 {
420 	return cdev->ops->get_requested_power && cdev->ops->state2power &&
421 		cdev->ops->power2state;
422 }
423 
424 int power_actor_get_max_power(struct thermal_cooling_device *,
425 			      struct thermal_zone_device *tz, u32 *max_power);
426 int power_actor_get_min_power(struct thermal_cooling_device *,
427 			      struct thermal_zone_device *tz, u32 *min_power);
428 int power_actor_set_power(struct thermal_cooling_device *,
429 			  struct thermal_instance *, u32);
430 struct thermal_zone_device *thermal_zone_device_register(const char *, int, int,
431 		void *, struct thermal_zone_device_ops *,
432 		struct thermal_zone_params *, int, int);
433 void thermal_zone_device_unregister(struct thermal_zone_device *);
434 
435 int thermal_zone_bind_cooling_device(struct thermal_zone_device *, int,
436 				     struct thermal_cooling_device *,
437 				     unsigned long, unsigned long,
438 				     unsigned int);
439 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *, int,
440 				       struct thermal_cooling_device *);
441 void thermal_zone_device_update(struct thermal_zone_device *,
442 				enum thermal_notify_event);
443 void thermal_zone_set_trips(struct thermal_zone_device *);
444 
445 struct thermal_cooling_device *thermal_cooling_device_register(char *, void *,
446 		const struct thermal_cooling_device_ops *);
447 struct thermal_cooling_device *
448 thermal_of_cooling_device_register(struct device_node *np, char *, void *,
449 				   const struct thermal_cooling_device_ops *);
450 void thermal_cooling_device_unregister(struct thermal_cooling_device *);
451 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name);
452 int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp);
453 int thermal_zone_get_slope(struct thermal_zone_device *tz);
454 int thermal_zone_get_offset(struct thermal_zone_device *tz);
455 
456 int get_tz_trend(struct thermal_zone_device *, int);
457 struct thermal_instance *get_thermal_instance(struct thermal_zone_device *,
458 		struct thermal_cooling_device *, int);
459 void thermal_cdev_update(struct thermal_cooling_device *);
460 void thermal_notify_framework(struct thermal_zone_device *, int);
461 #else
462 static inline bool cdev_is_power_actor(struct thermal_cooling_device *cdev)
463 { return false; }
464 static inline int power_actor_get_max_power(struct thermal_cooling_device *cdev,
465 			      struct thermal_zone_device *tz, u32 *max_power)
466 { return 0; }
467 static inline int power_actor_get_min_power(struct thermal_cooling_device *cdev,
468 					    struct thermal_zone_device *tz,
469 					    u32 *min_power)
470 { return -ENODEV; }
471 static inline int power_actor_set_power(struct thermal_cooling_device *cdev,
472 			  struct thermal_instance *tz, u32 power)
473 { return 0; }
474 static inline struct thermal_zone_device *thermal_zone_device_register(
475 	const char *type, int trips, int mask, void *devdata,
476 	struct thermal_zone_device_ops *ops,
477 	struct thermal_zone_params *tzp,
478 	int passive_delay, int polling_delay)
479 { return ERR_PTR(-ENODEV); }
480 static inline void thermal_zone_device_unregister(
481 	struct thermal_zone_device *tz)
482 { }
483 static inline int thermal_zone_bind_cooling_device(
484 	struct thermal_zone_device *tz, int trip,
485 	struct thermal_cooling_device *cdev,
486 	unsigned long upper, unsigned long lower,
487 	unsigned int weight)
488 { return -ENODEV; }
489 static inline int thermal_zone_unbind_cooling_device(
490 	struct thermal_zone_device *tz, int trip,
491 	struct thermal_cooling_device *cdev)
492 { return -ENODEV; }
493 static inline void thermal_zone_device_update(struct thermal_zone_device *tz,
494 					      enum thermal_notify_event event)
495 { }
496 static inline void thermal_zone_set_trips(struct thermal_zone_device *tz)
497 { }
498 static inline struct thermal_cooling_device *
499 thermal_cooling_device_register(char *type, void *devdata,
500 	const struct thermal_cooling_device_ops *ops)
501 { return ERR_PTR(-ENODEV); }
502 static inline struct thermal_cooling_device *
503 thermal_of_cooling_device_register(struct device_node *np,
504 	char *type, void *devdata, const struct thermal_cooling_device_ops *ops)
505 { return ERR_PTR(-ENODEV); }
506 static inline void thermal_cooling_device_unregister(
507 	struct thermal_cooling_device *cdev)
508 { }
509 static inline struct thermal_zone_device *thermal_zone_get_zone_by_name(
510 		const char *name)
511 { return ERR_PTR(-ENODEV); }
512 static inline int thermal_zone_get_temp(
513 		struct thermal_zone_device *tz, int *temp)
514 { return -ENODEV; }
515 static inline int thermal_zone_get_slope(
516 		struct thermal_zone_device *tz)
517 { return -ENODEV; }
518 static inline int thermal_zone_get_offset(
519 		struct thermal_zone_device *tz)
520 { return -ENODEV; }
521 static inline int get_tz_trend(struct thermal_zone_device *tz, int trip)
522 { return -ENODEV; }
523 static inline struct thermal_instance *
524 get_thermal_instance(struct thermal_zone_device *tz,
525 	struct thermal_cooling_device *cdev, int trip)
526 { return ERR_PTR(-ENODEV); }
527 static inline void thermal_cdev_update(struct thermal_cooling_device *cdev)
528 { }
529 static inline void thermal_notify_framework(struct thermal_zone_device *tz,
530 	int trip)
531 { }
532 #endif /* CONFIG_THERMAL */
533 
534 #if defined(CONFIG_NET) && IS_ENABLED(CONFIG_THERMAL)
535 extern int thermal_generate_netlink_event(struct thermal_zone_device *tz,
536 						enum events event);
537 #else
538 static inline int thermal_generate_netlink_event(struct thermal_zone_device *tz,
539 						enum events event)
540 {
541 	return 0;
542 }
543 #endif
544 
545 #endif /* __THERMAL_H__ */
546