1 // SPDX-License-Identifier: BSD-2-Clause 2 /* 3 * Copyright (c) 2023, STMicroelectronics 4 */ 5 6 #include <assert.h> 7 #include <compiler.h> 8 #include <config.h> 9 #include <drivers/regulator.h> 10 #include <initcall.h> 11 #include <keep.h> 12 #include <kernel/boot.h> 13 #include <kernel/delay.h> 14 #include <kernel/mutex.h> 15 #include <kernel/panic.h> 16 #include <kernel/pm.h> 17 #include <kernel/tee_time.h> 18 #include <kernel/thread.h> 19 #include <libfdt.h> 20 #include <limits.h> 21 #include <stdint.h> 22 #include <stdio.h> 23 #include <string.h> 24 #include <util.h> 25 26 static SLIST_HEAD(, regulator) regulator_device_list = 27 SLIST_HEAD_INITIALIZER(regulator); 28 29 static void lock_regulator(struct regulator *regulator) 30 { 31 /* 32 * Regulator operation may occur at runtime and during specific 33 * system power transition: power off, PM suspend and resume. 34 * These operate upon fastcall entries, under PSCI services 35 * execution, where non-secure world is not operational. In these 36 * cases we cannot take a mutex and will expect the mutex is 37 * unlocked. 38 */ 39 if (thread_get_id_may_fail() == THREAD_ID_INVALID) { 40 assert(!regulator->lock.state); 41 return; 42 } 43 44 mutex_lock(®ulator->lock); 45 } 46 47 static void unlock_regulator(struct regulator *regulator) 48 { 49 if (thread_get_id_may_fail() == THREAD_ID_INVALID) { 50 /* Path for PM sequences when with local Monitor */ 51 return; 52 } 53 54 mutex_unlock(®ulator->lock); 55 } 56 57 static TEE_Result set_state(struct regulator *regulator, bool on_not_off) 58 { 59 if (!regulator->ops->set_state) 60 return TEE_SUCCESS; 61 62 return regulator->ops->set_state(regulator, on_not_off); 63 } 64 65 static TEE_Result regulator_refcnt_enable(struct regulator *regulator) 66 { 67 TEE_Result res = TEE_ERROR_GENERIC; 68 69 FMSG("%s", regulator_name(regulator)); 70 71 if (regulator->supply) { 72 res = regulator_enable(regulator->supply); 73 if (res) 74 return res; 75 } 76 77 lock_regulator(regulator); 78 79 if (!regulator->refcount) { 80 res = set_state(regulator, true); 81 if (res) { 82 EMSG("regul %s set state failed with %#"PRIx32, 83 regulator_name(regulator), res); 84 85 unlock_regulator(regulator); 86 87 if (regulator->supply && 88 regulator_disable(regulator->supply)) 89 panic(); 90 91 return res; 92 } 93 } 94 95 regulator->refcount++; 96 if (!regulator->refcount) 97 panic(); 98 99 FMSG("%s refcount: %u", regulator_name(regulator), regulator->refcount); 100 101 unlock_regulator(regulator); 102 103 return TEE_SUCCESS; 104 } 105 106 TEE_Result regulator_enable(struct regulator *regulator) 107 { 108 assert(regulator); 109 FMSG("%s", regulator_name(regulator)); 110 111 if (regulator_is_always_on(regulator)) 112 return TEE_SUCCESS; 113 114 return regulator_refcnt_enable(regulator); 115 } 116 117 static TEE_Result regulator_refcnt_disable(struct regulator *regulator) 118 { 119 FMSG("%s", regulator_name(regulator)); 120 121 lock_regulator(regulator); 122 123 if (regulator->refcount == 1) { 124 TEE_Result res = set_state(regulator, false); 125 126 if (res) { 127 EMSG("regul %s set state failed with %#"PRIx32, 128 regulator_name(regulator), res); 129 unlock_regulator(regulator); 130 return res; 131 } 132 } 133 134 if (!regulator->refcount) { 135 EMSG("Unbalanced %s", regulator_name(regulator)); 136 panic(); 137 } 138 139 regulator->refcount--; 140 141 FMSG("%s refcount: %u", regulator_name(regulator), regulator->refcount); 142 143 unlock_regulator(regulator); 144 145 if (regulator->supply && regulator_disable(regulator->supply)) { 146 /* We can't leave this unbalanced */ 147 EMSG("Can't disable %s", regulator_name(regulator->supply)); 148 panic(); 149 } 150 151 return TEE_SUCCESS; 152 } 153 154 TEE_Result regulator_disable(struct regulator *regulator) 155 { 156 assert(regulator); 157 FMSG("%s", regulator_name(regulator)); 158 159 if (regulator_is_always_on(regulator)) 160 return TEE_SUCCESS; 161 162 return regulator_refcnt_disable(regulator); 163 } 164 165 bool regulator_is_enabled(struct regulator *regulator) 166 { 167 TEE_Result res = TEE_SUCCESS; 168 bool enabled = false; 169 170 if (!regulator->ops->get_state) 171 return true; 172 173 lock_regulator(regulator); 174 res = regulator->ops->get_state(regulator, &enabled); 175 unlock_regulator(regulator); 176 177 if (res) 178 EMSG("regul %s get state failed with %#"PRIx32, 179 regulator_name(regulator), res); 180 181 return !res && enabled; 182 } 183 184 TEE_Result regulator_set_voltage(struct regulator *regulator, int level_uv) 185 { 186 TEE_Result res = TEE_ERROR_GENERIC; 187 188 assert(regulator); 189 FMSG("%s %duV", regulator_name(regulator), level_uv); 190 191 if (level_uv < regulator->min_uv || level_uv > regulator->max_uv) 192 return TEE_ERROR_BAD_PARAMETERS; 193 194 if (level_uv == regulator->cur_uv) 195 return TEE_SUCCESS; 196 197 if (!regulator->ops->set_voltage) 198 return TEE_ERROR_NOT_SUPPORTED; 199 200 lock_regulator(regulator); 201 res = regulator->ops->set_voltage(regulator, level_uv); 202 unlock_regulator(regulator); 203 204 if (res) { 205 EMSG("regul %s set volt failed with %#"PRIx32, 206 regulator_name(regulator), res); 207 return res; 208 } 209 210 regulator->cur_uv = level_uv; 211 212 return TEE_SUCCESS; 213 } 214 215 TEE_Result regulator_supported_voltages(struct regulator *regulator, 216 struct regulator_voltages **voltages) 217 { 218 assert(regulator && voltages); 219 220 if (regulator->ops->supported_voltages) { 221 TEE_Result res = TEE_ERROR_GENERIC; 222 223 res = regulator->ops->supported_voltages(regulator, voltages); 224 if (res == TEE_SUCCESS) 225 return TEE_SUCCESS; 226 if (res != TEE_ERROR_NOT_SUPPORTED) 227 return res; 228 } 229 230 *voltages = ®ulator->voltages_fallback.desc; 231 232 return TEE_SUCCESS; 233 } 234 235 TEE_Result regulator_register(struct regulator *regulator) 236 { 237 TEE_Result res = TEE_SUCCESS; 238 int min_uv = 0; 239 int max_uv = 0; 240 int uv = 0; 241 242 if (!regulator || !regulator->ops || 243 regulator->flags & ~REGULATOR_FLAGS_MASK) 244 return TEE_ERROR_BAD_PARAMETERS; 245 246 regulator_get_range(regulator, &min_uv, &max_uv); 247 if (min_uv > max_uv) 248 return TEE_ERROR_BAD_PARAMETERS; 249 250 /* Sanitize regulator effective level */ 251 if (regulator->ops->get_voltage) { 252 res = regulator->ops->get_voltage(regulator, &uv); 253 if (res) 254 return res; 255 } else { 256 uv = min_uv; 257 } 258 regulator->cur_uv = uv; 259 260 if (uv < min_uv || uv > max_uv) { 261 res = regulator_set_voltage(regulator, min_uv); 262 if (res) 263 return res; 264 } 265 266 /* Unbalanced enable refcount to keep always-on regulators enabled */ 267 if (regulator_is_always_on(regulator)) { 268 res = regulator_refcnt_enable(regulator); 269 if (res) 270 return res; 271 } 272 273 /* Preset voltage list in case ops::supported_voltages is NULL */ 274 if (regulator->min_uv == regulator->max_uv) { 275 regulator->voltages_fallback.desc.type = VOLTAGE_TYPE_FULL_LIST; 276 regulator->voltages_fallback.desc.num_levels = 1; 277 regulator->voltages_fallback.levels[0] = regulator->min_uv; 278 } else { 279 regulator->voltages_fallback.desc.type = VOLTAGE_TYPE_INCREMENT; 280 regulator->voltages_fallback.levels[0] = regulator->min_uv; 281 regulator->voltages_fallback.levels[1] = regulator->max_uv; 282 regulator->voltages_fallback.levels[2] = 1; 283 } 284 285 SLIST_INSERT_HEAD(®ulator_device_list, regulator, link); 286 287 return TEE_SUCCESS; 288 } 289 290 /* 291 * Clean-up regulators that are not used. 292 */ 293 static TEE_Result regulator_core_cleanup(void) 294 { 295 struct regulator *regulator = NULL; 296 297 SLIST_FOREACH(regulator, ®ulator_device_list, link) { 298 if (!regulator->refcount) { 299 DMSG("disable %s", regulator_name(regulator)); 300 lock_regulator(regulator); 301 set_state(regulator, false /* disable */); 302 unlock_regulator(regulator); 303 } 304 } 305 306 regulator_print_tree(); 307 308 return TEE_SUCCESS; 309 } 310 311 release_init_resource(regulator_core_cleanup); 312 313 /* Return updated message buffer position of NULL on failure */ 314 static __printf(3, 4) char *add_msg(char *cur, char *end, const char *fmt, ...) 315 { 316 va_list ap = { }; 317 int max_len = end - cur; 318 int ret = 0; 319 320 va_start(ap, fmt); 321 ret = vsnprintf(cur, max_len, fmt, ap); 322 va_end(ap); 323 324 if (ret < 0 || ret >= max_len) 325 return NULL; 326 327 return cur + ret; 328 } 329 330 static struct regulator *find_next_regulator(struct regulator *parent, 331 struct regulator *sibling) 332 { 333 struct regulator *regulator = NULL; 334 335 if (sibling) 336 regulator = SLIST_NEXT(sibling, link); 337 else 338 regulator = SLIST_FIRST(®ulator_device_list); 339 340 while (regulator && regulator->supply != parent) 341 regulator = SLIST_NEXT(regulator, link); 342 343 return regulator; 344 } 345 346 /* Regulator is the last supplied one by its supply in the registered list */ 347 static bool regulator_is_supply_last_supplied(struct regulator *regulator) 348 { 349 return !find_next_regulator(regulator->supply, regulator); 350 } 351 352 /* Supply last node may already be printed for indentation level @cur_indent */ 353 static bool indent_with_empty_string(struct regulator *node_regulator, 354 int node_indent, int cur_indent) 355 { 356 struct regulator *r = node_regulator; 357 int n = 0; 358 359 /* Find supply at indentation level @node_indent - @cur_indent - 1 */ 360 for (n = 0; n < node_indent - cur_indent - 1; n++) 361 r = r->supply; 362 363 return regulator_is_supply_last_supplied(r); 364 } 365 366 static void __maybe_unused print_regulator(struct regulator *regulator, 367 int indent) 368 { 369 static const char * const level_unit[] = { "uV", "mV", "V" }; 370 int max_unit = ARRAY_SIZE(level_unit); 371 int level_max = 0; 372 int level_min = 0; 373 int level_cur = 0; 374 char msg_buf[128] = { }; 375 char *msg_end = msg_buf + sizeof(msg_buf); 376 char *msg = msg_buf; 377 int n_max = 0; 378 int n_min = 0; 379 int n_cur = 0; 380 int n = 0; 381 382 if (indent) { 383 /* Indent for root clock level */ 384 msg = add_msg(msg, msg_end, " "); 385 if (!msg) 386 goto out; 387 388 /* Indent for root supply to regulator supply levels */ 389 for (n = 0; n < indent - 1; n++) { 390 if (indent_with_empty_string(regulator, indent, n)) 391 msg = add_msg(msg, msg_end, " "); 392 else 393 msg = add_msg(msg, msg_end, "| "); 394 if (!msg) 395 goto out; 396 } 397 398 /* Regulator indentation */ 399 if (regulator_is_supply_last_supplied(regulator)) 400 msg = add_msg(msg, msg_end, "`-- "); 401 else 402 msg = add_msg(msg, msg_end, "|-- "); 403 404 if (!msg) 405 goto out; 406 } else { 407 /* Root supply indentation */ 408 msg = add_msg(msg, msg_end, "o- "); 409 } 410 411 regulator_get_range(regulator, &level_min, &level_max); 412 level_cur = regulator_get_voltage(regulator); 413 414 for (n_cur = 1; !(level_cur % 1000) && n_cur < max_unit; n_cur++) 415 level_cur /= 1000; 416 for (n_max = 1; !(level_max % 1000) && n_max < max_unit; n_max++) 417 level_max /= 1000; 418 for (n_min = 1; !(level_min % 1000) && n_min < max_unit; n_min++) 419 level_min /= 1000; 420 421 msg = add_msg(msg, msg_end, "%s \t(%3s / refcnt %u / flags %#"PRIx32 422 " / %d %s ", regulator_name(regulator), 423 regulator_is_enabled(regulator) ? "on " : "off", 424 regulator->refcount, regulator->flags, 425 level_cur, level_unit[n_cur - 1]); 426 if (!msg) 427 goto out; 428 429 if (level_min == level_max) 430 msg = add_msg(msg, msg_end, "fixed)"); 431 else if (level_max == INT_MAX) 432 msg = add_msg(msg, msg_end, "[%d %s .. MAX])", 433 level_min, level_unit[n_min - 1]); 434 else 435 msg = add_msg(msg, msg_end, "[%d %s .. %d %s])", 436 level_min, level_unit[n_min - 1], 437 level_max, level_unit[n_max - 1]); 438 439 out: 440 if (!msg) 441 snprintf(msg_end - 4, 4, "..."); 442 443 DMSG("%s", msg_buf); 444 } 445 446 static void print_tree(void) 447 { 448 struct regulator *regulator = NULL; 449 struct regulator *parent = NULL; 450 struct regulator *next = NULL; 451 int indent = -1; 452 453 while (true) { 454 next = find_next_regulator(parent, regulator); 455 if (next) { 456 print_regulator(next, indent + 1); 457 /* Enter the subtree of the next regulator */ 458 parent = next; 459 indent++; 460 regulator = NULL; 461 } else { 462 /* 463 * We've processed all children at this level. 464 * If parent is NULL we're at the top and are done. 465 */ 466 if (!parent) 467 break; 468 /* 469 * Move up one level to resume with the next 470 * regulator of the parent. 471 */ 472 regulator = parent; 473 parent = regulator->supply; 474 indent--; 475 } 476 } 477 } 478 479 void regulator_print_tree(void) 480 { 481 if (IS_ENABLED(CFG_DRIVERS_REGULATOR_PRINT_TREE) && 482 TRACE_LEVEL >= TRACE_DEBUG) { 483 DMSG("Regulator tree summary"); 484 if (SLIST_EMPTY(®ulator_device_list)) 485 DMSG("-- No registered regulator"); 486 else 487 print_tree(); 488 } 489 } 490