1 // SPDX-License-Identifier: BSD-2-Clause 2 /* 3 * Copyright (c) 2021, Linaro Limited 4 * Copyright (c) 2021, Bootlin 5 * Copyright (c) 2021, Linaro Limited 6 * Copyright (c) 2021, STMicroelectronics 7 */ 8 9 #include <assert.h> 10 #include <config.h> 11 #include <initcall.h> 12 #include <kernel/boot.h> 13 #include <kernel/dt.h> 14 #include <kernel/dt_driver.h> 15 #include <libfdt.h> 16 #include <malloc.h> 17 #include <sys/queue.h> 18 #include <tee_api_defines_extensions.h> 19 #include <tee_api_types.h> 20 21 /* 22 * struct dt_driver_probe - Node instance in secure FDT to probe a driver for 23 * 24 * @link: List hook 25 * @nodeoffset: Node offset of device referenced in the FDT 26 * @type: One of DT_DRIVER_* or DT_DRIVER_NOTYPE. 27 * @deferrals: Driver probe deferrals count 28 * @dt_drv: Matching driver to probe if found or NULL 29 * @dm: Matching reference if applicable or NULL 30 */ 31 struct dt_driver_probe { 32 int nodeoffset; 33 enum dt_driver_type type; 34 unsigned int deferrals; 35 const struct dt_driver *dt_drv; 36 const struct dt_device_match *dm; 37 TAILQ_ENTRY(dt_driver_probe) link; 38 }; 39 40 /* 41 * struct dt_driver_provider - DT related info on probed device 42 * 43 * Saves information on the probed device so that device 44 * drivers can get resources from DT phandle and related arguments. 45 * 46 * @nodeoffset: Node offset of device referenced in the FDT 47 * @type: One of DT_DRIVER_* or DT_DRIVER_NOTYPE. 48 * @provider_cells: Cells count in the FDT used by the driver's references 49 * @get_of_device: Function to get driver's device ref from phandle data 50 * @priv_data: Driver private data passed as @get_of_device argument 51 * @link: Reference in DT driver providers list 52 */ 53 struct dt_driver_provider { 54 int nodeoffset; 55 enum dt_driver_type type; 56 unsigned int provider_cells; 57 uint32_t phandle; 58 get_of_device_func get_of_device; 59 void *priv_data; 60 SLIST_ENTRY(dt_driver_provider) link; 61 }; 62 63 /* 64 * Device driver providers are able to provide a driver specific instance 65 * related to device phandle arguments found in the secure embedded FDT. 66 */ 67 static SLIST_HEAD(, dt_driver_provider) dt_driver_provider_list = 68 SLIST_HEAD_INITIALIZER(dt_driver_provider_list); 69 70 /* FDT nodes for which a matching driver is to be probed */ 71 static TAILQ_HEAD(dt_driver_probe_head, dt_driver_probe) dt_driver_probe_list = 72 TAILQ_HEAD_INITIALIZER(dt_driver_probe_list); 73 74 /* FDT nodes for which a matching driver has been successfully probed */ 75 static TAILQ_HEAD(, dt_driver_probe) dt_driver_ready_list = 76 TAILQ_HEAD_INITIALIZER(dt_driver_ready_list); 77 78 /* List of the nodes for which a compatible driver but reported a failure */ 79 static TAILQ_HEAD(, dt_driver_probe) dt_driver_failed_list = 80 TAILQ_HEAD_INITIALIZER(dt_driver_failed_list); 81 82 /* Flag enabled when a new node (possibly typed) is added in the probe list */ 83 static bool added_node; 84 85 /* Resolve drivers dependencies on core crypto layer */ 86 static bool tee_crypt_is_ready; 87 88 void dt_driver_crypt_init_complete(void) 89 { 90 assert(!tee_crypt_is_ready); 91 tee_crypt_is_ready = true; 92 } 93 94 TEE_Result dt_driver_get_crypto(void) 95 { 96 if (tee_crypt_is_ready) 97 return TEE_SUCCESS; 98 else 99 return TEE_ERROR_DEFER_DRIVER_INIT; 100 } 101 102 static void assert_type_is_valid(enum dt_driver_type type) 103 { 104 switch (type) { 105 case DT_DRIVER_NOTYPE: 106 case DT_DRIVER_CLK: 107 case DT_DRIVER_RSTCTRL: 108 case DT_DRIVER_UART: 109 case DT_DRIVER_GPIO: 110 case DT_DRIVER_I2C: 111 case DT_DRIVER_PINCTRL: 112 case DT_DRIVER_INTERRUPT: 113 case DT_DRIVER_REGULATOR: 114 return; 115 default: 116 assert(0); 117 } 118 } 119 120 /* 121 * Driver provider registering API functions 122 */ 123 124 TEE_Result dt_driver_register_provider(const void *fdt, int nodeoffset, 125 get_of_device_func get_of_device, 126 void *priv, enum dt_driver_type type) 127 { 128 struct dt_driver_provider *prv = NULL; 129 int provider_cells = 0; 130 uint32_t phandle = 0; 131 132 assert_type_is_valid(type); 133 134 provider_cells = fdt_get_dt_driver_cells(fdt, nodeoffset, type); 135 if (provider_cells < 0) { 136 DMSG("Failed to find provider cells: %d", provider_cells); 137 return TEE_ERROR_GENERIC; 138 } 139 140 phandle = fdt_get_phandle(fdt, nodeoffset); 141 if (phandle == (uint32_t)-1) { 142 DMSG("Failed to find provide phandle"); 143 return TEE_ERROR_GENERIC; 144 } 145 146 prv = calloc(1, sizeof(*prv)); 147 if (!prv) 148 return TEE_ERROR_OUT_OF_MEMORY; 149 150 prv->nodeoffset = nodeoffset; 151 prv->type = type; 152 prv->provider_cells = provider_cells; 153 prv->phandle = phandle; 154 prv->get_of_device = get_of_device; 155 prv->priv_data = priv; 156 157 SLIST_INSERT_HEAD(&dt_driver_provider_list, prv, link); 158 159 return TEE_SUCCESS; 160 } 161 162 static bool dt_driver_use_parent_controller(enum dt_driver_type type) 163 { 164 switch (type) { 165 case DT_DRIVER_PINCTRL: 166 return true; 167 default: 168 return false; 169 } 170 } 171 172 /* 173 * Helper functions for dt_drivers querying driver provider information 174 */ 175 176 int fdt_get_dt_driver_cells(const void *fdt, int nodeoffset, 177 enum dt_driver_type type) 178 { 179 const char *cells_name = NULL; 180 const fdt32_t *c = NULL; 181 int len = 0; 182 183 if (dt_driver_use_parent_controller(type)) 184 return 0; 185 186 switch (type) { 187 case DT_DRIVER_CLK: 188 cells_name = "#clock-cells"; 189 break; 190 case DT_DRIVER_INTERRUPT: 191 cells_name = "#interrupt-cells"; 192 break; 193 case DT_DRIVER_RSTCTRL: 194 cells_name = "#reset-cells"; 195 break; 196 case DT_DRIVER_GPIO: 197 cells_name = "#gpio-cells"; 198 break; 199 case DT_DRIVER_I2C: 200 case DT_DRIVER_REGULATOR: 201 return 0; 202 default: 203 panic(); 204 } 205 206 c = fdt_getprop(fdt, nodeoffset, cells_name, &len); 207 if (!c) 208 return len; 209 210 if (len != sizeof(*c)) 211 return -FDT_ERR_BADNCELLS; 212 213 return fdt32_to_cpu(*c); 214 } 215 216 unsigned int dt_driver_provider_cells(struct dt_driver_provider *prv) 217 { 218 return prv->provider_cells; 219 } 220 221 void *dt_driver_provider_priv_data(struct dt_driver_provider *prv) 222 { 223 return prv->priv_data; 224 } 225 226 struct dt_driver_provider * 227 dt_driver_get_provider_by_node(int nodeoffset, enum dt_driver_type type) 228 { 229 struct dt_driver_provider *prv = NULL; 230 231 SLIST_FOREACH(prv, &dt_driver_provider_list, link) 232 if (prv->nodeoffset == nodeoffset && prv->type == type) 233 return prv; 234 235 return NULL; 236 } 237 238 struct dt_driver_provider * 239 dt_driver_get_provider_by_phandle(uint32_t phandle, enum dt_driver_type type) 240 { 241 struct dt_driver_provider *prv = NULL; 242 243 SLIST_FOREACH(prv, &dt_driver_provider_list, link) 244 if (prv->phandle == phandle && prv->type == type) 245 return prv; 246 247 return NULL; 248 } 249 250 static TEE_Result device_from_provider_prop(struct dt_driver_provider *prv, 251 const void *fdt, int phandle_node, 252 const uint32_t *prop, void **device) 253 { 254 TEE_Result res = TEE_ERROR_GENERIC; 255 struct dt_pargs *pargs = NULL; 256 unsigned int n = 0; 257 258 pargs = calloc(1, prv->provider_cells * sizeof(uint32_t *) + 259 sizeof(*pargs)); 260 if (!pargs) 261 return TEE_ERROR_OUT_OF_MEMORY; 262 263 pargs->fdt = fdt; 264 pargs->phandle_node = phandle_node; 265 pargs->args_count = prv->provider_cells; 266 for (n = 0; n < prv->provider_cells; n++) 267 pargs->args[n] = fdt32_to_cpu(prop[n + 1]); 268 269 res = prv->get_of_device(pargs, prv->priv_data, device); 270 271 free(pargs); 272 273 return res; 274 } 275 276 TEE_Result dt_driver_device_from_parent(const void *fdt, int nodeoffset, 277 enum dt_driver_type type, void **device) 278 { 279 int parent = -1; 280 struct dt_driver_provider *prv = NULL; 281 282 assert(fdt == get_secure_dt()); 283 284 parent = fdt_parent_offset(fdt, nodeoffset); 285 if (parent < 0) 286 return TEE_ERROR_GENERIC; 287 288 prv = dt_driver_get_provider_by_node(parent, type); 289 if (!prv) { 290 /* No provider registered yet */ 291 return TEE_ERROR_DEFER_DRIVER_INIT; 292 } 293 294 return device_from_provider_prop(prv, fdt, nodeoffset, NULL, device); 295 } 296 297 TEE_Result dt_driver_device_from_node_idx_prop_phandle(const char *prop_name, 298 const void *fdt, 299 int nodeoffs, 300 unsigned int prop_index, 301 enum dt_driver_type type, 302 uint32_t phandle, 303 void **device) 304 { 305 int len = 0; 306 const uint32_t *prop = NULL; 307 int phandle_node_unused = -1; 308 struct dt_driver_provider *prv = NULL; 309 310 prop = fdt_getprop(fdt, nodeoffs, prop_name, &len); 311 if (!prop) { 312 if (len != -FDT_ERR_NOTFOUND) { 313 DMSG("Corrupted node %s", prop_name); 314 return TEE_ERROR_GENERIC; 315 } else { 316 DMSG("Property %s missing in node %s", prop_name, 317 fdt_get_name(fdt, nodeoffs, NULL)); 318 return TEE_ERROR_ITEM_NOT_FOUND; 319 } 320 } 321 322 prv = dt_driver_get_provider_by_phandle(phandle, type); 323 if (!prv) 324 return TEE_ERROR_DEFER_DRIVER_INIT; 325 326 prop_index *= dt_driver_provider_cells(prv); 327 if ((prop_index + 1) * sizeof(*prop) > (size_t)len) 328 return TEE_ERROR_ITEM_NOT_FOUND; 329 330 return device_from_provider_prop(prv, fdt, phandle_node_unused, 331 prop + prop_index, device); 332 } 333 334 TEE_Result dt_driver_device_from_node_idx_prop(const char *prop_name, 335 const void *fdt, int nodeoffset, 336 unsigned int prop_idx, 337 enum dt_driver_type type, 338 void **device) 339 { 340 int len = 0; 341 int idx = 0; 342 int idx32 = 0; 343 int prv_cells = 0; 344 int phandle_node = -1; 345 uint32_t phandle = 0; 346 const uint32_t *prop = NULL; 347 struct dt_driver_provider *prv = NULL; 348 349 prop = fdt_getprop(fdt, nodeoffset, prop_name, &len); 350 if (!prop) { 351 DMSG("Property %s missing in node %s", prop_name, 352 fdt_get_name(fdt, nodeoffset, NULL)); 353 return TEE_ERROR_ITEM_NOT_FOUND; 354 } 355 356 while (idx < len) { 357 idx32 = idx / sizeof(uint32_t); 358 phandle = fdt32_to_cpu(prop[idx32]); 359 if (!phandle) { 360 if (!prop_idx) 361 break; 362 idx += sizeof(phandle); 363 prop_idx--; 364 continue; 365 } 366 367 /* 368 * In some cases, pinctrl, i2c, nvmem, etc, the consumer phandle 369 * points directly to a subnode of the parent. In such cases, 370 * the provider does not have any "-cells" property and 371 * potentially no "phandle" property. 372 */ 373 if (dt_driver_use_parent_controller(type)) { 374 phandle_node = fdt_node_offset_by_phandle(fdt, phandle); 375 if (phandle_node < 0) 376 return TEE_ERROR_GENERIC; 377 378 nodeoffset = fdt_parent_offset(fdt, phandle_node); 379 if (nodeoffset < 0) 380 return TEE_ERROR_GENERIC; 381 382 prv = dt_driver_get_provider_by_node(nodeoffset, type); 383 if (!prv) 384 return TEE_ERROR_DEFER_DRIVER_INIT; 385 } else { 386 prv = dt_driver_get_provider_by_phandle(phandle, type); 387 if (!prv) 388 return TEE_ERROR_DEFER_DRIVER_INIT; 389 } 390 391 prv_cells = dt_driver_provider_cells(prv); 392 if (prop_idx) { 393 prop_idx--; 394 idx += sizeof(phandle) + prv_cells * sizeof(uint32_t); 395 continue; 396 } 397 398 return device_from_provider_prop(prv, fdt, phandle_node, 399 prop + idx32, device); 400 } 401 402 return TEE_ERROR_ITEM_NOT_FOUND; 403 } 404 405 static void __maybe_unused print_probe_list(const void *fdt __maybe_unused) 406 { 407 struct dt_driver_probe *elt = NULL; 408 unsigned int count = 0; 409 410 TAILQ_FOREACH(elt, &dt_driver_probe_list, link) 411 count++; 412 413 DMSG("Probe list: %u elements", count); 414 TAILQ_FOREACH(elt, &dt_driver_probe_list, link) 415 DMSG("|- Driver %s probes on node %s", 416 elt->dt_drv->name, 417 fdt_get_name(fdt, elt->nodeoffset, NULL)); 418 419 DMSG("`- Probe list end"); 420 421 count = 0; 422 TAILQ_FOREACH(elt, &dt_driver_failed_list, link) 423 count++; 424 425 DMSG("Failed list: %u elements", count); 426 TAILQ_FOREACH(elt, &dt_driver_failed_list, link) 427 EMSG("|- Driver %s on node %s failed", elt->dt_drv->name, 428 fdt_get_name(fdt, elt->nodeoffset, NULL)); 429 430 DMSG("`- Failed list end"); 431 } 432 433 /* 434 * Probe element: push to ready list if succeeds, push to probe list if probe 435 * if deferred, panic with an error trace otherwise. 436 */ 437 static TEE_Result probe_driver_node(const void *fdt, 438 struct dt_driver_probe *elt) 439 { 440 TEE_Result res = TEE_ERROR_GENERIC; 441 const char __maybe_unused *drv_name = NULL; 442 const char __maybe_unused *node_name = NULL; 443 444 node_name = fdt_get_name(fdt, elt->nodeoffset, NULL); 445 drv_name = elt->dt_drv->name; 446 447 if (!elt->dt_drv->probe) { 448 DMSG("No probe operator for driver %s, skipped", drv_name); 449 return TEE_SUCCESS; 450 } 451 452 FMSG("Probing %s on node %s", drv_name, node_name); 453 454 res = elt->dt_drv->probe(fdt, elt->nodeoffset, elt->dm->compat_data); 455 switch (res) { 456 case TEE_SUCCESS: 457 TAILQ_INSERT_HEAD(&dt_driver_ready_list, elt, link); 458 459 DMSG("element: %s on node %s initialized", drv_name, node_name); 460 break; 461 case TEE_ERROR_DEFER_DRIVER_INIT: 462 elt->deferrals++; 463 TAILQ_INSERT_TAIL(&dt_driver_probe_list, elt, link); 464 465 DMSG("element: %s on node %s deferred %u time(s)", drv_name, 466 node_name, elt->deferrals); 467 break; 468 case TEE_ERROR_NODE_DISABLED: 469 DMSG("element: %s on node %s is disabled", drv_name, node_name); 470 break; 471 default: 472 TAILQ_INSERT_HEAD(&dt_driver_failed_list, elt, link); 473 474 EMSG("Failed to probe %s on node %s: %#"PRIx32, 475 drv_name, node_name, res); 476 break; 477 } 478 479 return res; 480 } 481 482 static TEE_Result alloc_elt_and_probe(const void *fdt, int node, 483 const struct dt_driver *dt_drv, 484 const struct dt_device_match *dm) 485 { 486 struct dt_driver_probe *elt = NULL; 487 488 /* Will be freed when lists are released */ 489 elt = calloc(1, sizeof(*elt)); 490 if (!elt) 491 return TEE_ERROR_OUT_OF_MEMORY; 492 493 elt->nodeoffset = node; 494 elt->dt_drv = dt_drv; 495 elt->dm = dm; 496 elt->type = dt_drv->type; 497 498 return probe_driver_node(fdt, elt); 499 } 500 501 /* Lookup a compatible driver, possibly of a specific @type, for the FDT node */ 502 static TEE_Result probe_device_by_compat(const void *fdt, int node, 503 const char *compat, 504 enum dt_driver_type type) 505 { 506 const struct dt_driver *drv = NULL; 507 const struct dt_device_match *dm = NULL; 508 509 for_each_dt_driver(drv) { 510 if (drv->type != type) 511 continue; 512 513 for (dm = drv->match_table; dm && dm->compatible; dm++) 514 if (strcmp(dm->compatible, compat) == 0) 515 return alloc_elt_and_probe(fdt, node, drv, dm); 516 } 517 518 return TEE_ERROR_ITEM_NOT_FOUND; 519 } 520 521 /* 522 * Lookup the best matching compatible driver, possibly of a specific @type, 523 * for the FDT node. 524 */ 525 TEE_Result dt_driver_probe_device_by_node(const void *fdt, int nodeoffset, 526 enum dt_driver_type type) 527 { 528 int idx = 0; 529 int len = 0; 530 int count = 0; 531 const char *compat = NULL; 532 TEE_Result res = TEE_ERROR_GENERIC; 533 534 assert_type_is_valid(type); 535 536 count = fdt_stringlist_count(fdt, nodeoffset, "compatible"); 537 if (count < 0) 538 return TEE_ERROR_ITEM_NOT_FOUND; 539 540 for (idx = 0; idx < count; idx++) { 541 compat = fdt_stringlist_get(fdt, nodeoffset, "compatible", 542 idx, &len); 543 if (!compat) 544 return TEE_ERROR_GENERIC; 545 546 res = probe_device_by_compat(fdt, nodeoffset, compat, type); 547 548 if (res != TEE_ERROR_ITEM_NOT_FOUND) 549 return res; 550 } 551 552 return TEE_ERROR_ITEM_NOT_FOUND; 553 } 554 555 static TEE_Result process_probe_list(const void *fdt) 556 { 557 struct dt_driver_probe *elt = NULL; 558 struct dt_driver_probe *prev = NULL; 559 static unsigned int __maybe_unused loop_count; 560 static unsigned int __maybe_unused deferral_loop_count; 561 bool __maybe_unused one_deferred = false; 562 bool one_probed_ok = false; 563 564 do { 565 loop_count++; 566 FMSG("Probe loop %u after %u for deferral(s)", loop_count, 567 deferral_loop_count); 568 569 /* Hack here for TRACE_DEBUG messages on probe list elements */ 570 if (TRACE_LEVEL >= TRACE_FLOW) 571 print_probe_list(fdt); 572 573 if (TAILQ_EMPTY(&dt_driver_probe_list)) 574 return TEE_SUCCESS; 575 576 /* 577 * Probe from current end to top. Deferred probed node are 578 * pushed back after current tail for the next probe round. 579 * Reset probe result flags and see status after probe round. 580 */ 581 one_deferred = false; 582 one_probed_ok = false; 583 added_node = false; 584 585 TAILQ_FOREACH_REVERSE_SAFE(elt, &dt_driver_probe_list, 586 dt_driver_probe_head, link, prev) { 587 TAILQ_REMOVE(&dt_driver_probe_list, elt, link); 588 589 switch (probe_driver_node(fdt, elt)) { 590 case TEE_SUCCESS: 591 one_probed_ok = true; 592 break; 593 case TEE_ERROR_DEFER_DRIVER_INIT: 594 one_deferred = true; 595 break; 596 default: 597 break; 598 } 599 } 600 601 if (one_deferred) 602 deferral_loop_count++; 603 604 } while (added_node || one_probed_ok); 605 606 DMSG("Unresolved dependencies after %u rounds, %u deferred", 607 loop_count, deferral_loop_count); 608 609 if (one_deferred) 610 return TEE_ERROR_DEFER_DRIVER_INIT; 611 else 612 return TEE_ERROR_GENERIC; 613 } 614 615 static int driver_probe_compare(struct dt_driver_probe *candidate, 616 struct dt_driver_probe *elt) 617 { 618 if (candidate->nodeoffset != elt->nodeoffset || 619 candidate->type != elt->type) 620 return 1; 621 622 assert(elt->dt_drv == candidate->dt_drv); 623 return 0; 624 } 625 626 /* 627 * Return TEE_SUCCESS if compatible found 628 * TEE_ERROR_OUT_OF_MEMORY if heap is exhausted 629 */ 630 static TEE_Result add_node_to_probe(const void *fdt, int node, 631 const struct dt_driver *dt_drv, 632 const struct dt_device_match *dm) 633 { 634 const char __maybe_unused *node_name = fdt_get_name(fdt, node, NULL); 635 const char __maybe_unused *drv_name = dt_drv->name; 636 struct dt_driver_probe *elt = NULL; 637 struct dt_driver_probe elt_new = { 638 .dm = dm, 639 .dt_drv = dt_drv, 640 .nodeoffset = node, 641 .type = dt_drv->type, 642 }; 643 644 /* If node/type found in probe list or ready list, nothing to do */ 645 TAILQ_FOREACH(elt, &dt_driver_probe_list, link) 646 if (!driver_probe_compare(&elt_new, elt)) 647 return TEE_SUCCESS; 648 649 TAILQ_FOREACH(elt, &dt_driver_ready_list, link) 650 if (!driver_probe_compare(&elt_new, elt)) 651 return TEE_SUCCESS; 652 653 elt = malloc(sizeof(*elt)); 654 if (!elt) 655 return TEE_ERROR_OUT_OF_MEMORY; 656 657 DMSG("element: %s on node %s", node_name, drv_name); 658 659 memcpy(elt, &elt_new, sizeof(*elt)); 660 661 added_node = true; 662 663 TAILQ_INSERT_TAIL(&dt_driver_probe_list, elt, link); 664 665 /* Hack here for TRACE_DEBUG messages on current probe list elements */ 666 if (TRACE_LEVEL >= TRACE_FLOW) 667 print_probe_list(fdt); 668 669 return TEE_SUCCESS; 670 } 671 672 /* 673 * Add a node to the probe list if a dt_driver matches target compatible. 674 * 675 * If @type is DT_DRIVER_ANY, probe list can hold only 1 driver to probe for 676 * the node. A node may probe several drivers if have a unique driver type. 677 * 678 * Return TEE_SUCCESS if compatible found 679 * TEE_ERROR_ITEM_NOT_FOUND if no matching driver 680 * TEE_ERROR_OUT_OF_MEMORY if heap is exhausted 681 */ 682 static TEE_Result add_probe_node_by_compat(const void *fdt, int node, 683 const char *compat) 684 { 685 TEE_Result res = TEE_ERROR_ITEM_NOT_FOUND; 686 const struct dt_driver *dt_drv = NULL; 687 const struct dt_device_match *dm = NULL; 688 uint32_t found_types = 0; 689 690 for_each_dt_driver(dt_drv) { 691 for (dm = dt_drv->match_table; dm && dm->compatible; dm++) { 692 if (strcmp(dm->compatible, compat) == 0) { 693 assert(dt_drv->type < 32); 694 695 res = add_node_to_probe(fdt, node, dt_drv, dm); 696 if (res) 697 return res; 698 699 if (found_types & BIT(dt_drv->type)) { 700 EMSG("Driver %s multi hit on type %u", 701 dt_drv->name, dt_drv->type); 702 panic(); 703 } 704 found_types |= BIT(dt_drv->type); 705 706 /* Matching found for this driver, try next */ 707 break; 708 } 709 } 710 } 711 712 return res; 713 } 714 715 /* 716 * Add the node to the probe list if matching compatible drivers are found. 717 * Follow node's compatible property list ordering to find matching driver. 718 */ 719 TEE_Result dt_driver_maybe_add_probe_node(const void *fdt, int node) 720 { 721 int idx = 0; 722 int len = 0; 723 int count = 0; 724 const char *compat = NULL; 725 TEE_Result res = TEE_ERROR_GENERIC; 726 727 if (fdt_get_status(fdt, node) == DT_STATUS_DISABLED) 728 return TEE_SUCCESS; 729 730 count = fdt_stringlist_count(fdt, node, "compatible"); 731 if (count < 0) 732 return TEE_SUCCESS; 733 734 for (idx = 0; idx < count; idx++) { 735 compat = fdt_stringlist_get(fdt, node, "compatible", idx, &len); 736 assert(compat && len > 0); 737 738 res = add_probe_node_by_compat(fdt, node, compat); 739 740 /* Stop lookup if something was found */ 741 if (res != TEE_ERROR_ITEM_NOT_FOUND) 742 return res; 743 } 744 745 return TEE_SUCCESS; 746 } 747 748 static void parse_node(const void *fdt, int node) 749 { 750 TEE_Result __maybe_unused res = TEE_ERROR_GENERIC; 751 int subnode = 0; 752 753 fdt_for_each_subnode(subnode, fdt, node) { 754 res = dt_driver_maybe_add_probe_node(fdt, subnode); 755 if (res) { 756 EMSG("Failed on node %s with %#"PRIx32, 757 fdt_get_name(fdt, subnode, NULL), res); 758 panic(); 759 } 760 761 /* 762 * Rescursively parse the FDT, skipping disabled nodes. 763 * FDT is expected reliable and core shall have sufficient 764 * stack depth to possibly parse all DT nodes. 765 */ 766 if (IS_ENABLED(CFG_DRIVERS_DT_RECURSIVE_PROBE)) { 767 if (fdt_get_status(fdt, subnode) == DT_STATUS_DISABLED) 768 continue; 769 770 parse_node(fdt, subnode); 771 } 772 } 773 } 774 775 /* 776 * Parse FDT for nodes and save in probe list the node for which a dt_driver 777 * matches node's compatible property. 778 */ 779 static TEE_Result probe_dt_drivers_early(void) 780 { 781 TEE_Result res = TEE_ERROR_GENERIC; 782 const void *fdt = NULL; 783 784 fdt = get_secure_dt(); 785 if (!fdt) 786 return TEE_SUCCESS; 787 788 parse_node(fdt, fdt_path_offset(fdt, "/")); 789 790 res = process_probe_list(fdt); 791 if (res == TEE_ERROR_DEFER_DRIVER_INIT) { 792 DMSG("Deferred drivers probing"); 793 print_probe_list(fdt); 794 res = TEE_SUCCESS; 795 } 796 797 return res; 798 } 799 800 static TEE_Result probe_dt_drivers(void) 801 { 802 TEE_Result res = TEE_ERROR_GENERIC; 803 const void *fdt = NULL; 804 805 fdt = get_secure_dt(); 806 if (!fdt) 807 return TEE_SUCCESS; 808 809 res = process_probe_list(fdt); 810 if (res || !TAILQ_EMPTY(&dt_driver_failed_list)) { 811 EMSG("Probe sequence result: %#"PRIx32, res); 812 print_probe_list(fdt); 813 panic(); 814 } 815 816 return TEE_SUCCESS; 817 } 818 819 early_init_late(probe_dt_drivers_early); 820 driver_init(probe_dt_drivers); 821 822 static TEE_Result release_probe_lists(void) 823 { 824 struct dt_driver_probe *elt = NULL; 825 struct dt_driver_probe *next = NULL; 826 struct dt_driver_provider *prov = NULL; 827 struct dt_driver_provider *next_prov = NULL; 828 const void *fdt = NULL; 829 830 fdt = get_secure_dt(); 831 if (!fdt) 832 return TEE_SUCCESS; 833 834 assert(fdt && TAILQ_EMPTY(&dt_driver_probe_list)); 835 836 TAILQ_FOREACH_SAFE(elt, &dt_driver_ready_list, link, next) 837 free(elt); 838 839 TAILQ_FOREACH_SAFE(elt, &dt_driver_failed_list, link, next) 840 free(elt); 841 842 SLIST_FOREACH_SAFE(prov, &dt_driver_provider_list, link, next_prov) 843 free(prov); 844 845 return TEE_SUCCESS; 846 } 847 848 release_init_resource(release_probe_lists); 849 850 /* 851 * Simple bus support: handy to parse subnodes 852 */ 853 static TEE_Result simple_bus_probe(const void *fdt, int node, 854 const void *compat_data __unused) 855 { 856 TEE_Result res = TEE_ERROR_GENERIC; 857 int subnode = 0; 858 859 fdt_for_each_subnode(subnode, fdt, node) { 860 res = dt_driver_maybe_add_probe_node(fdt, subnode); 861 if (res) { 862 EMSG("Failed on node %s with %#"PRIx32, 863 fdt_get_name(fdt, subnode, NULL), res); 864 panic(); 865 } 866 } 867 868 return TEE_SUCCESS; 869 } 870 871 static const struct dt_device_match simple_bus_match_table[] = { 872 { .compatible = "simple-bus" }, 873 { } 874 }; 875 876 DEFINE_DT_DRIVER(simple_bus_dt_driver) = { 877 .name = "simple-bus", 878 .match_table = simple_bus_match_table, 879 .probe = simple_bus_probe, 880 }; 881