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_pm_aware.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 /* Access protection mutex complying the power state transitions context */ 30 static void lock_regulator(struct regulator *regulator) 31 { 32 mutex_pm_aware_lock(®ulator->mutex); 33 } 34 35 static void unlock_regulator(struct regulator *regulator) 36 { 37 mutex_pm_aware_unlock(®ulator->mutex); 38 } 39 40 static TEE_Result set_state(struct regulator *regulator, bool on_not_off) 41 { 42 if (!regulator->ops->set_state) 43 return TEE_SUCCESS; 44 45 return regulator->ops->set_state(regulator, on_not_off); 46 } 47 48 static TEE_Result regulator_refcnt_enable(struct regulator *regulator) 49 { 50 TEE_Result res = TEE_ERROR_GENERIC; 51 52 FMSG("%s", regulator_name(regulator)); 53 54 if (regulator->supply) { 55 res = regulator_enable(regulator->supply); 56 if (res) 57 return res; 58 } 59 60 lock_regulator(regulator); 61 62 if (!regulator->refcount) { 63 res = set_state(regulator, true); 64 if (res) { 65 EMSG("regul %s set state failed with %#"PRIx32, 66 regulator_name(regulator), res); 67 68 unlock_regulator(regulator); 69 70 if (regulator->supply && 71 regulator_disable(regulator->supply)) 72 panic(); 73 74 return res; 75 } 76 } 77 78 regulator->refcount++; 79 if (!regulator->refcount) 80 panic(); 81 82 FMSG("%s refcount: %u", regulator_name(regulator), regulator->refcount); 83 84 unlock_regulator(regulator); 85 86 return TEE_SUCCESS; 87 } 88 89 TEE_Result regulator_enable(struct regulator *regulator) 90 { 91 assert(regulator); 92 FMSG("%s", regulator_name(regulator)); 93 94 if (regulator_is_always_on(regulator)) 95 return TEE_SUCCESS; 96 97 return regulator_refcnt_enable(regulator); 98 } 99 100 static TEE_Result regulator_refcnt_disable(struct regulator *regulator) 101 { 102 FMSG("%s", regulator_name(regulator)); 103 104 lock_regulator(regulator); 105 106 if (regulator->refcount == 1) { 107 TEE_Result res = set_state(regulator, false); 108 109 if (res) { 110 EMSG("regul %s set state failed with %#"PRIx32, 111 regulator_name(regulator), res); 112 unlock_regulator(regulator); 113 return res; 114 } 115 } 116 117 if (!regulator->refcount) { 118 EMSG("Unbalanced %s", regulator_name(regulator)); 119 panic(); 120 } 121 122 regulator->refcount--; 123 124 FMSG("%s refcount: %u", regulator_name(regulator), regulator->refcount); 125 126 unlock_regulator(regulator); 127 128 if (regulator->supply && regulator_disable(regulator->supply)) { 129 /* We can't leave this unbalanced */ 130 EMSG("Can't disable %s", regulator_name(regulator->supply)); 131 panic(); 132 } 133 134 return TEE_SUCCESS; 135 } 136 137 TEE_Result regulator_disable(struct regulator *regulator) 138 { 139 assert(regulator); 140 FMSG("%s", regulator_name(regulator)); 141 142 if (regulator_is_always_on(regulator)) 143 return TEE_SUCCESS; 144 145 return regulator_refcnt_disable(regulator); 146 } 147 148 bool regulator_is_enabled(struct regulator *regulator) 149 { 150 TEE_Result res = TEE_SUCCESS; 151 bool enabled = false; 152 153 if (!regulator->ops->get_state) 154 return true; 155 156 lock_regulator(regulator); 157 res = regulator->ops->get_state(regulator, &enabled); 158 unlock_regulator(regulator); 159 160 if (res) 161 EMSG("regul %s get state failed with %#"PRIx32, 162 regulator_name(regulator), res); 163 164 return !res && enabled; 165 } 166 167 int regulator_get_voltage(struct regulator *regulator) 168 { 169 TEE_Result res = TEE_SUCCESS; 170 int level_uv = regulator->min_uv; 171 172 if (regulator->ops->get_voltage) { 173 res = regulator->ops->get_voltage(regulator, &level_uv); 174 if (res) { 175 EMSG("%s get_voltage failed with %#"PRIx32, 176 regulator_name(regulator), res); 177 level_uv = 0; 178 } 179 } 180 181 return level_uv; 182 } 183 184 TEE_Result regulator_set_voltage(struct regulator *regulator, int level_uv) 185 { 186 TEE_Result res = TEE_ERROR_GENERIC; 187 int cur_uv = 0; 188 189 assert(regulator); 190 FMSG("%s %duV", regulator_name(regulator), level_uv); 191 192 if (level_uv < regulator->min_uv || level_uv > regulator->max_uv) 193 return TEE_ERROR_BAD_PARAMETERS; 194 195 cur_uv = regulator_get_voltage(regulator); 196 if (level_uv == cur_uv) 197 return TEE_SUCCESS; 198 199 if (!regulator->ops->set_voltage) 200 return TEE_ERROR_NOT_SUPPORTED; 201 202 lock_regulator(regulator); 203 res = regulator->ops->set_voltage(regulator, level_uv); 204 unlock_regulator(regulator); 205 206 if (res) { 207 EMSG("regul %s set volt failed with %#"PRIx32, 208 regulator_name(regulator), res); 209 return res; 210 } 211 212 return TEE_SUCCESS; 213 } 214 215 TEE_Result regulator_supported_voltages(struct regulator *regulator, 216 struct regulator_voltages_desc **desc, 217 const int **levels) 218 { 219 TEE_Result res = TEE_ERROR_NOT_SUPPORTED; 220 221 assert(regulator && desc && levels); 222 223 if (regulator->ops->supported_voltages) 224 res = regulator->ops->supported_voltages(regulator, desc, 225 levels); 226 if (res == TEE_ERROR_NOT_SUPPORTED) { 227 *desc = ®ulator->voltages_fallback.desc; 228 *levels = regulator->voltages_fallback.levels; 229 } else if (res) { 230 return res; 231 } 232 233 if ((*desc)->type == VOLTAGE_TYPE_FULL_LIST) { 234 assert((*desc)->num_levels); 235 assert((*levels)[0] >= regulator->min_uv); 236 assert((*levels)[(*desc)->num_levels - 1] <= regulator->max_uv); 237 } else if ((*desc)->type == VOLTAGE_TYPE_INCREMENT) { 238 assert((*levels)[0] >= regulator->min_uv); 239 assert((*levels)[1] <= regulator->max_uv); 240 } else { 241 assert(0); 242 } 243 244 return TEE_SUCCESS; 245 } 246 247 TEE_Result regulator_register(struct regulator *regulator) 248 { 249 TEE_Result res = TEE_SUCCESS; 250 int min_uv = 0; 251 int max_uv = 0; 252 int uv = 0; 253 254 if (!regulator || !regulator->ops || 255 regulator->flags & ~REGULATOR_FLAGS_MASK) 256 return TEE_ERROR_BAD_PARAMETERS; 257 258 mutex_pm_aware_init(®ulator->mutex); 259 260 regulator_get_range(regulator, &min_uv, &max_uv); 261 if (min_uv > max_uv) 262 return TEE_ERROR_BAD_PARAMETERS; 263 264 /* Sanitize regulator effective level */ 265 uv = regulator_get_voltage(regulator); 266 267 if (uv < min_uv || uv > max_uv) { 268 res = regulator_set_voltage(regulator, min_uv); 269 if (res) 270 return res; 271 } 272 273 /* Unbalanced enable refcount to keep always-on regulators enabled */ 274 if (regulator_is_always_on(regulator)) { 275 res = regulator_refcnt_enable(regulator); 276 if (res) 277 return res; 278 } 279 280 /* Preset voltage list in case ops::supported_voltages is NULL */ 281 if (regulator->min_uv == regulator->max_uv) { 282 regulator->voltages_fallback.desc.type = VOLTAGE_TYPE_FULL_LIST; 283 regulator->voltages_fallback.desc.num_levels = 1; 284 regulator->voltages_fallback.levels[0] = regulator->min_uv; 285 } else { 286 regulator->voltages_fallback.desc.type = VOLTAGE_TYPE_INCREMENT; 287 regulator->voltages_fallback.levels[0] = regulator->min_uv; 288 regulator->voltages_fallback.levels[1] = regulator->max_uv; 289 regulator->voltages_fallback.levels[2] = 1; 290 } 291 292 SLIST_INSERT_HEAD(®ulator_device_list, regulator, link); 293 294 return TEE_SUCCESS; 295 } 296 297 /* 298 * Clean-up regulators that are not used. 299 */ 300 static TEE_Result regulator_core_cleanup(void) 301 { 302 struct regulator *regulator = NULL; 303 304 SLIST_FOREACH(regulator, ®ulator_device_list, link) { 305 if (!regulator->refcount) { 306 DMSG("disable %s", regulator_name(regulator)); 307 lock_regulator(regulator); 308 set_state(regulator, false /* disable */); 309 unlock_regulator(regulator); 310 } 311 } 312 313 if (TRACE_LEVEL >= TRACE_DEBUG) 314 regulator_print_tree(); 315 316 return TEE_SUCCESS; 317 } 318 319 release_init_resource(regulator_core_cleanup); 320 321 /* Return updated message buffer position of NULL on failure */ 322 static __printf(3, 4) char *add_msg(char *cur, char *end, const char *fmt, ...) 323 { 324 va_list ap = { }; 325 int max_len = end - cur; 326 int ret = 0; 327 328 va_start(ap, fmt); 329 ret = vsnprintf(cur, max_len, fmt, ap); 330 va_end(ap); 331 332 if (ret < 0 || ret >= max_len) 333 return NULL; 334 335 return cur + ret; 336 } 337 338 static struct regulator *find_next_regulator(struct regulator *parent, 339 struct regulator *sibling) 340 { 341 struct regulator *regulator = NULL; 342 343 if (sibling) 344 regulator = SLIST_NEXT(sibling, link); 345 else 346 regulator = SLIST_FIRST(®ulator_device_list); 347 348 while (regulator && regulator->supply != parent) 349 regulator = SLIST_NEXT(regulator, link); 350 351 return regulator; 352 } 353 354 /* Regulator is the last supplied one by its supply in the registered list */ 355 static bool regulator_is_supply_last_supplied(struct regulator *regulator) 356 { 357 return !find_next_regulator(regulator->supply, regulator); 358 } 359 360 /* Supply last node may already be printed for indentation level @cur_indent */ 361 static bool indent_with_empty_string(struct regulator *node_regulator, 362 int node_indent, int cur_indent) 363 { 364 struct regulator *r = node_regulator; 365 int n = 0; 366 367 /* Find supply at indentation level @node_indent - @cur_indent - 1 */ 368 for (n = 0; n < node_indent - cur_indent - 1; n++) 369 r = r->supply; 370 371 return regulator_is_supply_last_supplied(r); 372 } 373 374 static void __maybe_unused print_regulator(struct regulator *regulator, 375 int indent) 376 { 377 static const char * const level_unit[] = { "uV", "mV", "V" }; 378 int max_unit = ARRAY_SIZE(level_unit); 379 int level_max = 0; 380 int level_min = 0; 381 int level_cur = 0; 382 char msg_buf[128] = { }; 383 char *msg_end = msg_buf + sizeof(msg_buf); 384 char *msg = msg_buf; 385 int n_max = 0; 386 int n_min = 0; 387 int n_cur = 0; 388 int n = 0; 389 390 if (indent) { 391 /* Indent for root clock level */ 392 msg = add_msg(msg, msg_end, " "); 393 if (!msg) 394 goto out; 395 396 /* Indent for root supply to regulator supply levels */ 397 for (n = 0; n < indent - 1; n++) { 398 if (indent_with_empty_string(regulator, indent, n)) 399 msg = add_msg(msg, msg_end, " "); 400 else 401 msg = add_msg(msg, msg_end, "| "); 402 if (!msg) 403 goto out; 404 } 405 406 /* Regulator indentation */ 407 if (regulator_is_supply_last_supplied(regulator)) 408 msg = add_msg(msg, msg_end, "`-- "); 409 else 410 msg = add_msg(msg, msg_end, "|-- "); 411 412 if (!msg) 413 goto out; 414 } else { 415 /* Root supply indentation */ 416 msg = add_msg(msg, msg_end, "o- "); 417 } 418 419 regulator_get_range(regulator, &level_min, &level_max); 420 level_cur = regulator_get_voltage(regulator); 421 422 for (n_cur = 1; !(level_cur % 1000) && n_cur < max_unit; n_cur++) 423 level_cur /= 1000; 424 for (n_max = 1; !(level_max % 1000) && n_max < max_unit; n_max++) 425 level_max /= 1000; 426 for (n_min = 1; !(level_min % 1000) && n_min < max_unit; n_min++) 427 level_min /= 1000; 428 429 msg = add_msg(msg, msg_end, "%s \t(%3s / refcnt %u / flags %#"PRIx32 430 " / %d %s ", regulator_name(regulator), 431 regulator_is_enabled(regulator) ? "on " : "off", 432 regulator->refcount, regulator->flags, 433 level_cur, level_unit[n_cur - 1]); 434 if (!msg) 435 goto out; 436 437 if (level_min == level_max) 438 msg = add_msg(msg, msg_end, "fixed)"); 439 else if (level_max == INT_MAX) 440 msg = add_msg(msg, msg_end, "[%d %s .. MAX])", 441 level_min, level_unit[n_min - 1]); 442 else 443 msg = add_msg(msg, msg_end, "[%d %s .. %d %s])", 444 level_min, level_unit[n_min - 1], 445 level_max, level_unit[n_max - 1]); 446 447 out: 448 if (!msg) 449 snprintf(msg_end - 4, 4, "..."); 450 451 IMSG("%s", msg_buf); 452 } 453 454 static void print_tree(void) 455 { 456 struct regulator *regulator = NULL; 457 struct regulator *parent = NULL; 458 struct regulator *next = NULL; 459 int indent = -1; 460 461 while (true) { 462 next = find_next_regulator(parent, regulator); 463 if (next) { 464 print_regulator(next, indent + 1); 465 /* Enter the subtree of the next regulator */ 466 parent = next; 467 indent++; 468 regulator = NULL; 469 } else { 470 /* 471 * We've processed all children at this level. 472 * If parent is NULL we're at the top and are done. 473 */ 474 if (!parent) 475 break; 476 /* 477 * Move up one level to resume with the next 478 * regulator of the parent. 479 */ 480 regulator = parent; 481 parent = regulator->supply; 482 indent--; 483 } 484 } 485 } 486 487 void regulator_print_tree(void) 488 { 489 if (IS_ENABLED(CFG_DRIVERS_REGULATOR_PRINT_TREE) && 490 TRACE_LEVEL >= TRACE_INFO) { 491 IMSG("Regulator tree summary"); 492 if (SLIST_EMPTY(®ulator_device_list)) 493 IMSG("-- No registered regulator"); 494 else 495 print_tree(); 496 } 497 } 498