1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright 2024, Intel Corporation
4 *
5 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
6 *
7 * Thermal zone tempalates handling for thermal core testing.
8 */
9
10 #define pr_fmt(fmt) "thermal-testing: " fmt
11
12 #include <linux/debugfs.h>
13 #include <linux/idr.h>
14 #include <linux/list.h>
15 #include <linux/thermal.h>
16
17 #include "thermal_testing.h"
18
19 #define TT_MAX_FILE_NAME_LENGTH 16
20
21 /**
22 * struct tt_thermal_zone - Testing thermal zone template
23 *
24 * Represents a template of a thermal zone that can be used for registering
25 * a test thermal zone with the thermal core.
26 *
27 * @list_node: Node in the list of all testing thermal zone templates.
28 * @trips: List of trip point templates for this thermal zone template.
29 * @d_tt_zone: Directory in debugfs representing this template.
30 * @tz: Test thermal zone based on this template, if present.
31 * @lock: Mutex for synchronizing changes of this template.
32 * @ida: IDA for trip point IDs.
33 * @id: The ID of this template for the debugfs interface.
34 * @temp: Temperature value.
35 * @tz_temp: Current thermal zone temperature (after registration).
36 * @num_trips: Number of trip points in the @trips list.
37 * @refcount: Reference counter for usage and removal synchronization.
38 */
39 struct tt_thermal_zone {
40 struct list_head list_node;
41 struct list_head trips;
42 struct dentry *d_tt_zone;
43 struct thermal_zone_device *tz;
44 struct mutex lock;
45 struct ida ida;
46 int id;
47 int temp;
48 int tz_temp;
49 unsigned int num_trips;
50 unsigned int refcount;
51 };
52
53 DEFINE_GUARD(tt_zone, struct tt_thermal_zone *, mutex_lock(&_T->lock), mutex_unlock(&_T->lock))
54
55 /**
56 * struct tt_trip - Testing trip point template
57 *
58 * Represents a template of a trip point to be used for populating a trip point
59 * during the registration of a thermal zone based on a given zone template.
60 *
61 * @list_node: Node in the list of all trip templates in the zone template.
62 * @trip: Trip point data to use for thernal zone registration.
63 * @id: The ID of this trip template for the debugfs interface.
64 */
65 struct tt_trip {
66 struct list_head list_node;
67 struct thermal_trip trip;
68 int id;
69 };
70
71 /*
72 * It is both questionable and potentially problematic from the sychnronization
73 * perspective to attempt to manipulate debugfs from within a debugfs file
74 * "write" operation, so auxiliary work items are used for that. The majority
75 * of zone-related command functions have a part that runs from a workqueue and
76 * make changes in debugs, among other things.
77 */
78 struct tt_work {
79 struct work_struct work;
80 struct tt_thermal_zone *tt_zone;
81 struct tt_trip *tt_trip;
82 };
83
tt_work_of_work(struct work_struct * work)84 static inline struct tt_work *tt_work_of_work(struct work_struct *work)
85 {
86 return container_of(work, struct tt_work, work);
87 }
88
89 static LIST_HEAD(tt_thermal_zones);
90 static DEFINE_IDA(tt_thermal_zones_ida);
91 static DEFINE_MUTEX(tt_thermal_zones_lock);
92
tt_int_get(void * data,u64 * val)93 static int tt_int_get(void *data, u64 *val)
94 {
95 *val = *(int *)data;
96 return 0;
97 }
tt_int_set(void * data,u64 val)98 static int tt_int_set(void *data, u64 val)
99 {
100 if ((int)val < THERMAL_TEMP_INVALID)
101 return -EINVAL;
102
103 *(int *)data = val;
104 return 0;
105 }
106 DEFINE_DEBUGFS_ATTRIBUTE_SIGNED(tt_int_attr, tt_int_get, tt_int_set, "%lld\n");
107 DEFINE_DEBUGFS_ATTRIBUTE(tt_unsigned_int_attr, tt_int_get, tt_int_set, "%llu\n");
108
tt_zone_tz_temp_get(void * data,u64 * val)109 static int tt_zone_tz_temp_get(void *data, u64 *val)
110 {
111 struct tt_thermal_zone *tt_zone = data;
112
113 guard(tt_zone)(tt_zone);
114
115 if (!tt_zone->tz)
116 return -EBUSY;
117
118 *val = tt_zone->tz_temp;
119
120 return 0;
121 }
tt_zone_tz_temp_set(void * data,u64 val)122 static int tt_zone_tz_temp_set(void *data, u64 val)
123 {
124 struct tt_thermal_zone *tt_zone = data;
125
126 guard(tt_zone)(tt_zone);
127
128 if (!tt_zone->tz)
129 return -EBUSY;
130
131 WRITE_ONCE(tt_zone->tz_temp, val);
132 thermal_zone_device_update(tt_zone->tz, THERMAL_EVENT_TEMP_SAMPLE);
133
134 return 0;
135 }
136 DEFINE_DEBUGFS_ATTRIBUTE_SIGNED(tt_zone_tz_temp_attr, tt_zone_tz_temp_get,
137 tt_zone_tz_temp_set, "%lld\n");
138
tt_zone_free_trips(struct tt_thermal_zone * tt_zone)139 static void tt_zone_free_trips(struct tt_thermal_zone *tt_zone)
140 {
141 struct tt_trip *tt_trip, *aux;
142
143 list_for_each_entry_safe(tt_trip, aux, &tt_zone->trips, list_node) {
144 list_del(&tt_trip->list_node);
145 ida_free(&tt_zone->ida, tt_trip->id);
146 kfree(tt_trip);
147 }
148 }
149
tt_zone_free(struct tt_thermal_zone * tt_zone)150 static void tt_zone_free(struct tt_thermal_zone *tt_zone)
151 {
152 tt_zone_free_trips(tt_zone);
153 ida_free(&tt_thermal_zones_ida, tt_zone->id);
154 ida_destroy(&tt_zone->ida);
155 kfree(tt_zone);
156 }
157
tt_add_tz_work_fn(struct work_struct * work)158 static void tt_add_tz_work_fn(struct work_struct *work)
159 {
160 struct tt_work *tt_work = tt_work_of_work(work);
161 struct tt_thermal_zone *tt_zone = tt_work->tt_zone;
162 char f_name[TT_MAX_FILE_NAME_LENGTH];
163
164 kfree(tt_work);
165
166 snprintf(f_name, TT_MAX_FILE_NAME_LENGTH, "tz%d", tt_zone->id);
167 tt_zone->d_tt_zone = debugfs_create_dir(f_name, d_testing);
168 if (IS_ERR(tt_zone->d_tt_zone)) {
169 tt_zone_free(tt_zone);
170 return;
171 }
172
173 debugfs_create_file_unsafe("temp", 0600, tt_zone->d_tt_zone, tt_zone,
174 &tt_zone_tz_temp_attr);
175
176 debugfs_create_file_unsafe("init_temp", 0600, tt_zone->d_tt_zone,
177 &tt_zone->temp, &tt_int_attr);
178
179 guard(mutex)(&tt_thermal_zones_lock);
180
181 list_add_tail(&tt_zone->list_node, &tt_thermal_zones);
182 }
183
tt_add_tz(void)184 int tt_add_tz(void)
185 {
186 int ret;
187
188 struct tt_thermal_zone *tt_zone __free(kfree) = kzalloc_obj(*tt_zone);
189 if (!tt_zone)
190 return -ENOMEM;
191
192 struct tt_work *tt_work __free(kfree) = kzalloc_obj(*tt_work);
193 if (!tt_work)
194 return -ENOMEM;
195
196 INIT_LIST_HEAD(&tt_zone->trips);
197 mutex_init(&tt_zone->lock);
198 ida_init(&tt_zone->ida);
199 tt_zone->temp = THERMAL_TEMP_INVALID;
200
201 ret = ida_alloc(&tt_thermal_zones_ida, GFP_KERNEL);
202 if (ret < 0)
203 return ret;
204
205 tt_zone->id = ret;
206
207 INIT_WORK(&tt_work->work, tt_add_tz_work_fn);
208 tt_work->tt_zone = no_free_ptr(tt_zone);
209 tt_queue_work(&(no_free_ptr(tt_work)->work));
210
211 return 0;
212 }
213
tt_del_tz_work_fn(struct work_struct * work)214 static void tt_del_tz_work_fn(struct work_struct *work)
215 {
216 struct tt_work *tt_work = tt_work_of_work(work);
217 struct tt_thermal_zone *tt_zone = tt_work->tt_zone;
218
219 kfree(tt_work);
220
221 debugfs_remove(tt_zone->d_tt_zone);
222 tt_zone_free(tt_zone);
223 }
224
tt_zone_unregister_tz(struct tt_thermal_zone * tt_zone)225 static void tt_zone_unregister_tz(struct tt_thermal_zone *tt_zone)
226 {
227 guard(tt_zone)(tt_zone);
228
229 if (tt_zone->tz) {
230 thermal_zone_device_unregister(tt_zone->tz);
231 tt_zone->tz = NULL;
232 }
233 }
234
tt_del_tz(const char * arg)235 int tt_del_tz(const char *arg)
236 {
237 struct tt_thermal_zone *tt_zone, *aux;
238 int ret;
239 int id;
240
241 ret = kstrtoint(arg, 10, &id);
242 if (ret < 0)
243 return ret;
244
245 struct tt_work *tt_work __free(kfree) = kzalloc_obj(*tt_work);
246 if (!tt_work)
247 return -ENOMEM;
248
249 guard(mutex)(&tt_thermal_zones_lock);
250
251 ret = -EINVAL;
252 list_for_each_entry_safe(tt_zone, aux, &tt_thermal_zones, list_node) {
253 if (tt_zone->id == id) {
254 if (tt_zone->refcount) {
255 ret = -EBUSY;
256 } else {
257 list_del(&tt_zone->list_node);
258 ret = 0;
259 }
260 break;
261 }
262 }
263
264 if (ret)
265 return ret;
266
267 tt_zone_unregister_tz(tt_zone);
268
269 INIT_WORK(&tt_work->work, tt_del_tz_work_fn);
270 tt_work->tt_zone = tt_zone;
271 tt_queue_work(&(no_free_ptr(tt_work)->work));
272
273 return 0;
274 }
275
tt_get_tt_zone(const char * arg)276 static struct tt_thermal_zone *tt_get_tt_zone(const char *arg)
277 {
278 struct tt_thermal_zone *tt_zone;
279 int ret, id;
280
281 ret = kstrtoint(arg, 10, &id);
282 if (ret < 0)
283 return ERR_PTR(ret);
284
285 guard(mutex)(&tt_thermal_zones_lock);
286
287 list_for_each_entry(tt_zone, &tt_thermal_zones, list_node) {
288 if (tt_zone->id == id) {
289 tt_zone->refcount++;
290 return tt_zone;
291 }
292 }
293
294 return ERR_PTR(-EINVAL);
295 }
296
tt_put_tt_zone(struct tt_thermal_zone * tt_zone)297 static void tt_put_tt_zone(struct tt_thermal_zone *tt_zone)
298 {
299 guard(mutex)(&tt_thermal_zones_lock);
300
301 tt_zone->refcount--;
302 }
303
304 DEFINE_FREE(put_tt_zone, struct tt_thermal_zone *,
305 if (!IS_ERR_OR_NULL(_T)) tt_put_tt_zone(_T))
306
tt_zone_add_trip_work_fn(struct work_struct * work)307 static void tt_zone_add_trip_work_fn(struct work_struct *work)
308 {
309 struct tt_work *tt_work = tt_work_of_work(work);
310 struct tt_thermal_zone *tt_zone = tt_work->tt_zone;
311 struct tt_trip *tt_trip = tt_work->tt_trip;
312 char d_name[TT_MAX_FILE_NAME_LENGTH];
313
314 kfree(tt_work);
315
316 snprintf(d_name, TT_MAX_FILE_NAME_LENGTH, "trip_%d_temp", tt_trip->id);
317 debugfs_create_file_unsafe(d_name, 0600, tt_zone->d_tt_zone,
318 &tt_trip->trip.temperature, &tt_int_attr);
319
320 snprintf(d_name, TT_MAX_FILE_NAME_LENGTH, "trip_%d_hyst", tt_trip->id);
321 debugfs_create_file_unsafe(d_name, 0600, tt_zone->d_tt_zone,
322 &tt_trip->trip.hysteresis, &tt_unsigned_int_attr);
323
324 tt_put_tt_zone(tt_zone);
325 }
326
tt_zone_add_trip(const char * arg)327 int tt_zone_add_trip(const char *arg)
328 {
329 int id;
330
331 struct tt_work *tt_work __free(kfree) = kzalloc_obj(*tt_work);
332 if (!tt_work)
333 return -ENOMEM;
334
335 struct tt_trip *tt_trip __free(kfree) = kzalloc_obj(*tt_trip);
336 if (!tt_trip)
337 return -ENOMEM;
338
339 struct tt_thermal_zone *tt_zone __free(put_tt_zone) = tt_get_tt_zone(arg);
340 if (IS_ERR(tt_zone))
341 return PTR_ERR(tt_zone);
342
343 id = ida_alloc(&tt_zone->ida, GFP_KERNEL);
344 if (id < 0)
345 return id;
346
347 tt_trip->trip.type = THERMAL_TRIP_ACTIVE;
348 tt_trip->trip.temperature = THERMAL_TEMP_INVALID;
349 tt_trip->trip.flags = THERMAL_TRIP_FLAG_RW;
350 tt_trip->id = id;
351
352 guard(tt_zone)(tt_zone);
353
354 list_add_tail(&tt_trip->list_node, &tt_zone->trips);
355 tt_zone->num_trips++;
356
357 INIT_WORK(&tt_work->work, tt_zone_add_trip_work_fn);
358 tt_work->tt_zone = no_free_ptr(tt_zone);
359 tt_work->tt_trip = no_free_ptr(tt_trip);
360 tt_queue_work(&(no_free_ptr(tt_work)->work));
361
362 return 0;
363 }
364
tt_zone_get_temp(struct thermal_zone_device * tz,int * temp)365 static int tt_zone_get_temp(struct thermal_zone_device *tz, int *temp)
366 {
367 struct tt_thermal_zone *tt_zone = thermal_zone_device_priv(tz);
368
369 *temp = READ_ONCE(tt_zone->tz_temp);
370
371 if (*temp < THERMAL_TEMP_INVALID)
372 return -ENODATA;
373
374 return 0;
375 }
376
377 static const struct thermal_zone_device_ops tt_zone_ops = {
378 .get_temp = tt_zone_get_temp,
379 };
380
tt_zone_register_tz(struct tt_thermal_zone * tt_zone)381 static int tt_zone_register_tz(struct tt_thermal_zone *tt_zone)
382 {
383 struct thermal_zone_device *tz;
384 struct tt_trip *tt_trip;
385 int i;
386
387 guard(tt_zone)(tt_zone);
388
389 if (tt_zone->tz)
390 return -EINVAL;
391
392 struct thermal_trip *trips __free(kfree) = kzalloc_objs(*trips,
393 tt_zone->num_trips);
394 if (!trips)
395 return -ENOMEM;
396
397 i = 0;
398 list_for_each_entry(tt_trip, &tt_zone->trips, list_node)
399 trips[i++] = tt_trip->trip;
400
401 tt_zone->tz_temp = tt_zone->temp;
402
403 tz = thermal_zone_device_register_with_trips("test_tz", trips, i, tt_zone,
404 &tt_zone_ops, NULL, 0, 0);
405 if (IS_ERR(tz))
406 return PTR_ERR(tz);
407
408 tt_zone->tz = tz;
409
410 thermal_zone_device_enable(tz);
411
412 return 0;
413 }
414
tt_zone_reg(const char * arg)415 int tt_zone_reg(const char *arg)
416 {
417 struct tt_thermal_zone *tt_zone __free(put_tt_zone) = tt_get_tt_zone(arg);
418 if (IS_ERR(tt_zone))
419 return PTR_ERR(tt_zone);
420
421 return tt_zone_register_tz(tt_zone);
422 }
423
tt_zone_unreg(const char * arg)424 int tt_zone_unreg(const char *arg)
425 {
426 struct tt_thermal_zone *tt_zone __free(put_tt_zone) = tt_get_tt_zone(arg);
427 if (IS_ERR(tt_zone))
428 return PTR_ERR(tt_zone);
429
430 tt_zone_unregister_tz(tt_zone);
431
432 return 0;
433 }
434
tt_zone_cleanup(void)435 void tt_zone_cleanup(void)
436 {
437 struct tt_thermal_zone *tt_zone, *aux;
438
439 list_for_each_entry_safe(tt_zone, aux, &tt_thermal_zones, list_node) {
440 tt_zone_unregister_tz(tt_zone);
441
442 list_del(&tt_zone->list_node);
443
444 tt_zone_free(tt_zone);
445 }
446 }
447