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 #include <linux/workqueue.h> 17 18 #include "thermal_testing.h" 19 20 #define TT_MAX_FILE_NAME_LENGTH 16 21 22 /** 23 * struct tt_thermal_zone - Testing thermal zone template 24 * 25 * Represents a template of a thermal zone that can be used for registering 26 * a test thermal zone with the thermal core. 27 * 28 * @list_node: Node in the list of all testing thermal zone templates. 29 * @trips: List of trip point templates for this thermal zone template. 30 * @d_tt_zone: Directory in debugfs representing this template. 31 * @tz: Test thermal zone based on this template, if present. 32 * @lock: Mutex for synchronizing changes of this template. 33 * @ida: IDA for trip point IDs. 34 * @id: The ID of this template for the debugfs interface. 35 * @temp: Temperature value. 36 * @tz_temp: Current thermal zone temperature (after registration). 37 * @num_trips: Number of trip points in the @trips list. 38 * @refcount: Reference counter for usage and removal synchronization. 39 */ 40 struct tt_thermal_zone { 41 struct list_head list_node; 42 struct list_head trips; 43 struct dentry *d_tt_zone; 44 struct thermal_zone_device *tz; 45 struct mutex lock; 46 struct ida ida; 47 int id; 48 int temp; 49 int tz_temp; 50 unsigned int num_trips; 51 unsigned int refcount; 52 }; 53 54 DEFINE_GUARD(tt_zone, struct tt_thermal_zone *, mutex_lock(&_T->lock), mutex_unlock(&_T->lock)) 55 56 /** 57 * struct tt_trip - Testing trip point template 58 * 59 * Represents a template of a trip point to be used for populating a trip point 60 * during the registration of a thermal zone based on a given zone template. 61 * 62 * @list_node: Node in the list of all trip templates in the zone template. 63 * @trip: Trip point data to use for thernal zone registration. 64 * @id: The ID of this trip template for the debugfs interface. 65 */ 66 struct tt_trip { 67 struct list_head list_node; 68 struct thermal_trip trip; 69 int id; 70 }; 71 72 /* 73 * It is both questionable and potentially problematic from the sychnronization 74 * perspective to attempt to manipulate debugfs from within a debugfs file 75 * "write" operation, so auxiliary work items are used for that. The majority 76 * of zone-related command functions have a part that runs from a workqueue and 77 * make changes in debugs, among other things. 78 */ 79 struct tt_work { 80 struct work_struct work; 81 struct tt_thermal_zone *tt_zone; 82 struct tt_trip *tt_trip; 83 }; 84 85 static inline struct tt_work *tt_work_of_work(struct work_struct *work) 86 { 87 return container_of(work, struct tt_work, work); 88 } 89 90 static LIST_HEAD(tt_thermal_zones); 91 static DEFINE_IDA(tt_thermal_zones_ida); 92 static DEFINE_MUTEX(tt_thermal_zones_lock); 93 94 static int tt_int_get(void *data, u64 *val) 95 { 96 *val = *(int *)data; 97 return 0; 98 } 99 static int tt_int_set(void *data, u64 val) 100 { 101 if ((int)val < THERMAL_TEMP_INVALID) 102 return -EINVAL; 103 104 *(int *)data = val; 105 return 0; 106 } 107 DEFINE_DEBUGFS_ATTRIBUTE_SIGNED(tt_int_attr, tt_int_get, tt_int_set, "%lld\n"); 108 DEFINE_DEBUGFS_ATTRIBUTE(tt_unsigned_int_attr, tt_int_get, tt_int_set, "%llu\n"); 109 110 static int tt_zone_tz_temp_get(void *data, u64 *val) 111 { 112 struct tt_thermal_zone *tt_zone = data; 113 114 guard(tt_zone)(tt_zone); 115 116 if (!tt_zone->tz) 117 return -EBUSY; 118 119 *val = tt_zone->tz_temp; 120 121 return 0; 122 } 123 static int tt_zone_tz_temp_set(void *data, u64 val) 124 { 125 struct tt_thermal_zone *tt_zone = data; 126 127 guard(tt_zone)(tt_zone); 128 129 if (!tt_zone->tz) 130 return -EBUSY; 131 132 WRITE_ONCE(tt_zone->tz_temp, val); 133 thermal_zone_device_update(tt_zone->tz, THERMAL_EVENT_TEMP_SAMPLE); 134 135 return 0; 136 } 137 DEFINE_DEBUGFS_ATTRIBUTE_SIGNED(tt_zone_tz_temp_attr, tt_zone_tz_temp_get, 138 tt_zone_tz_temp_set, "%lld\n"); 139 140 static void tt_zone_free_trips(struct tt_thermal_zone *tt_zone) 141 { 142 struct tt_trip *tt_trip, *aux; 143 144 list_for_each_entry_safe(tt_trip, aux, &tt_zone->trips, list_node) { 145 list_del(&tt_trip->list_node); 146 ida_free(&tt_zone->ida, tt_trip->id); 147 kfree(tt_trip); 148 } 149 } 150 151 static void tt_zone_free(struct tt_thermal_zone *tt_zone) 152 { 153 tt_zone_free_trips(tt_zone); 154 ida_free(&tt_thermal_zones_ida, tt_zone->id); 155 ida_destroy(&tt_zone->ida); 156 kfree(tt_zone); 157 } 158 159 static void tt_add_tz_work_fn(struct work_struct *work) 160 { 161 struct tt_work *tt_work = tt_work_of_work(work); 162 struct tt_thermal_zone *tt_zone = tt_work->tt_zone; 163 char f_name[TT_MAX_FILE_NAME_LENGTH]; 164 165 kfree(tt_work); 166 167 snprintf(f_name, TT_MAX_FILE_NAME_LENGTH, "tz%d", tt_zone->id); 168 tt_zone->d_tt_zone = debugfs_create_dir(f_name, d_testing); 169 if (IS_ERR(tt_zone->d_tt_zone)) { 170 tt_zone_free(tt_zone); 171 return; 172 } 173 174 debugfs_create_file_unsafe("temp", 0600, tt_zone->d_tt_zone, tt_zone, 175 &tt_zone_tz_temp_attr); 176 177 debugfs_create_file_unsafe("init_temp", 0600, tt_zone->d_tt_zone, 178 &tt_zone->temp, &tt_int_attr); 179 180 guard(mutex)(&tt_thermal_zones_lock); 181 182 list_add_tail(&tt_zone->list_node, &tt_thermal_zones); 183 } 184 185 int tt_add_tz(void) 186 { 187 int ret; 188 189 struct tt_thermal_zone *tt_zone __free(kfree) = kzalloc_obj(*tt_zone); 190 if (!tt_zone) 191 return -ENOMEM; 192 193 struct tt_work *tt_work __free(kfree) = kzalloc_obj(*tt_work); 194 if (!tt_work) 195 return -ENOMEM; 196 197 INIT_LIST_HEAD(&tt_zone->trips); 198 mutex_init(&tt_zone->lock); 199 ida_init(&tt_zone->ida); 200 tt_zone->temp = THERMAL_TEMP_INVALID; 201 202 ret = ida_alloc(&tt_thermal_zones_ida, GFP_KERNEL); 203 if (ret < 0) 204 return ret; 205 206 tt_zone->id = ret; 207 208 INIT_WORK(&tt_work->work, tt_add_tz_work_fn); 209 tt_work->tt_zone = no_free_ptr(tt_zone); 210 schedule_work(&(no_free_ptr(tt_work)->work)); 211 212 return 0; 213 } 214 215 static void tt_del_tz_work_fn(struct work_struct *work) 216 { 217 struct tt_work *tt_work = tt_work_of_work(work); 218 struct tt_thermal_zone *tt_zone = tt_work->tt_zone; 219 220 kfree(tt_work); 221 222 debugfs_remove(tt_zone->d_tt_zone); 223 tt_zone_free(tt_zone); 224 } 225 226 static void tt_zone_unregister_tz(struct tt_thermal_zone *tt_zone) 227 { 228 guard(tt_zone)(tt_zone); 229 230 if (tt_zone->tz) { 231 thermal_zone_device_unregister(tt_zone->tz); 232 tt_zone->tz = NULL; 233 } 234 } 235 236 int tt_del_tz(const char *arg) 237 { 238 struct tt_thermal_zone *tt_zone, *aux; 239 int ret; 240 int id; 241 242 ret = sscanf(arg, "%d", &id); 243 if (ret != 1) 244 return -EINVAL; 245 246 struct tt_work *tt_work __free(kfree) = kzalloc_obj(*tt_work); 247 if (!tt_work) 248 return -ENOMEM; 249 250 guard(mutex)(&tt_thermal_zones_lock); 251 252 ret = -EINVAL; 253 list_for_each_entry_safe(tt_zone, aux, &tt_thermal_zones, list_node) { 254 if (tt_zone->id == id) { 255 if (tt_zone->refcount) { 256 ret = -EBUSY; 257 } else { 258 list_del(&tt_zone->list_node); 259 ret = 0; 260 } 261 break; 262 } 263 } 264 265 if (ret) 266 return ret; 267 268 tt_zone_unregister_tz(tt_zone); 269 270 INIT_WORK(&tt_work->work, tt_del_tz_work_fn); 271 tt_work->tt_zone = tt_zone; 272 schedule_work(&(no_free_ptr(tt_work)->work)); 273 274 return 0; 275 } 276 277 static struct tt_thermal_zone *tt_get_tt_zone(const char *arg) 278 { 279 struct tt_thermal_zone *tt_zone; 280 int ret, id; 281 282 ret = sscanf(arg, "%d", &id); 283 if (ret != 1) 284 return ERR_PTR(-EINVAL); 285 286 guard(mutex)(&tt_thermal_zones_lock); 287 288 list_for_each_entry(tt_zone, &tt_thermal_zones, list_node) { 289 if (tt_zone->id == id) { 290 tt_zone->refcount++; 291 return tt_zone; 292 } 293 } 294 295 return ERR_PTR(-EINVAL); 296 } 297 298 static void tt_put_tt_zone(struct tt_thermal_zone *tt_zone) 299 { 300 guard(mutex)(&tt_thermal_zones_lock); 301 302 tt_zone->refcount--; 303 } 304 305 DEFINE_FREE(put_tt_zone, struct tt_thermal_zone *, 306 if (!IS_ERR_OR_NULL(_T)) tt_put_tt_zone(_T)) 307 308 static void tt_zone_add_trip_work_fn(struct work_struct *work) 309 { 310 struct tt_work *tt_work = tt_work_of_work(work); 311 struct tt_thermal_zone *tt_zone = tt_work->tt_zone; 312 struct tt_trip *tt_trip = tt_work->tt_trip; 313 char d_name[TT_MAX_FILE_NAME_LENGTH]; 314 315 kfree(tt_work); 316 317 snprintf(d_name, TT_MAX_FILE_NAME_LENGTH, "trip_%d_temp", tt_trip->id); 318 debugfs_create_file_unsafe(d_name, 0600, tt_zone->d_tt_zone, 319 &tt_trip->trip.temperature, &tt_int_attr); 320 321 snprintf(d_name, TT_MAX_FILE_NAME_LENGTH, "trip_%d_hyst", tt_trip->id); 322 debugfs_create_file_unsafe(d_name, 0600, tt_zone->d_tt_zone, 323 &tt_trip->trip.hysteresis, &tt_unsigned_int_attr); 324 325 tt_put_tt_zone(tt_zone); 326 } 327 328 int tt_zone_add_trip(const char *arg) 329 { 330 int id; 331 332 struct tt_work *tt_work __free(kfree) = kzalloc_obj(*tt_work); 333 if (!tt_work) 334 return -ENOMEM; 335 336 struct tt_trip *tt_trip __free(kfree) = kzalloc_obj(*tt_trip); 337 if (!tt_trip) 338 return -ENOMEM; 339 340 struct tt_thermal_zone *tt_zone __free(put_tt_zone) = tt_get_tt_zone(arg); 341 if (IS_ERR(tt_zone)) 342 return PTR_ERR(tt_zone); 343 344 id = ida_alloc(&tt_zone->ida, GFP_KERNEL); 345 if (id < 0) 346 return id; 347 348 tt_trip->trip.type = THERMAL_TRIP_ACTIVE; 349 tt_trip->trip.temperature = THERMAL_TEMP_INVALID; 350 tt_trip->trip.flags = THERMAL_TRIP_FLAG_RW; 351 tt_trip->id = id; 352 353 guard(tt_zone)(tt_zone); 354 355 list_add_tail(&tt_trip->list_node, &tt_zone->trips); 356 tt_zone->num_trips++; 357 358 INIT_WORK(&tt_work->work, tt_zone_add_trip_work_fn); 359 tt_work->tt_zone = no_free_ptr(tt_zone); 360 tt_work->tt_trip = no_free_ptr(tt_trip); 361 schedule_work(&(no_free_ptr(tt_work)->work)); 362 363 return 0; 364 } 365 366 static int tt_zone_get_temp(struct thermal_zone_device *tz, int *temp) 367 { 368 struct tt_thermal_zone *tt_zone = thermal_zone_device_priv(tz); 369 370 *temp = READ_ONCE(tt_zone->tz_temp); 371 372 if (*temp < THERMAL_TEMP_INVALID) 373 return -ENODATA; 374 375 return 0; 376 } 377 378 static const struct thermal_zone_device_ops tt_zone_ops = { 379 .get_temp = tt_zone_get_temp, 380 }; 381 382 static int tt_zone_register_tz(struct tt_thermal_zone *tt_zone) 383 { 384 struct thermal_zone_device *tz; 385 struct tt_trip *tt_trip; 386 int i; 387 388 guard(tt_zone)(tt_zone); 389 390 if (tt_zone->tz) 391 return -EINVAL; 392 393 struct thermal_trip *trips __free(kfree) = kzalloc_objs(*trips, 394 tt_zone->num_trips, 395 GFP_KERNEL); 396 if (!trips) 397 return -ENOMEM; 398 399 i = 0; 400 list_for_each_entry(tt_trip, &tt_zone->trips, list_node) 401 trips[i++] = tt_trip->trip; 402 403 tt_zone->tz_temp = tt_zone->temp; 404 405 tz = thermal_zone_device_register_with_trips("test_tz", trips, i, tt_zone, 406 &tt_zone_ops, NULL, 0, 0); 407 if (IS_ERR(tz)) 408 return PTR_ERR(tz); 409 410 tt_zone->tz = tz; 411 412 thermal_zone_device_enable(tz); 413 414 return 0; 415 } 416 417 int tt_zone_reg(const char *arg) 418 { 419 struct tt_thermal_zone *tt_zone __free(put_tt_zone) = tt_get_tt_zone(arg); 420 if (IS_ERR(tt_zone)) 421 return PTR_ERR(tt_zone); 422 423 return tt_zone_register_tz(tt_zone); 424 } 425 426 int tt_zone_unreg(const char *arg) 427 { 428 struct tt_thermal_zone *tt_zone __free(put_tt_zone) = tt_get_tt_zone(arg); 429 if (IS_ERR(tt_zone)) 430 return PTR_ERR(tt_zone); 431 432 tt_zone_unregister_tz(tt_zone); 433 434 return 0; 435 } 436 437 void tt_zone_cleanup(void) 438 { 439 struct tt_thermal_zone *tt_zone, *aux; 440 441 list_for_each_entry_safe(tt_zone, aux, &tt_thermal_zones, list_node) { 442 tt_zone_unregister_tz(tt_zone); 443 444 list_del(&tt_zone->list_node); 445 446 tt_zone_free(tt_zone); 447 } 448 } 449