1 /* 2 * Copyright (c) 2011 The Chromium OS Authors. 3 * See file CREDITS for list of people who contributed to this 4 * project. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as 8 * published by the Free Software Foundation; either version 2 of 9 * the License, or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 19 * MA 02111-1307 USA 20 */ 21 22 #include <common.h> 23 #include <serial.h> 24 #include <libfdt.h> 25 #include <fdtdec.h> 26 27 #include <asm/gpio.h> 28 29 DECLARE_GLOBAL_DATA_PTR; 30 31 /* 32 * Here are the type we know about. One day we might allow drivers to 33 * register. For now we just put them here. The COMPAT macro allows us to 34 * turn this into a sparse list later, and keeps the ID with the name. 35 */ 36 #define COMPAT(id, name) name 37 static const char * const compat_names[COMPAT_COUNT] = { 38 COMPAT(UNKNOWN, "<none>"), 39 COMPAT(NVIDIA_TEGRA20_USB, "nvidia,tegra20-ehci"), 40 COMPAT(NVIDIA_TEGRA20_I2C, "nvidia,tegra20-i2c"), 41 COMPAT(NVIDIA_TEGRA20_DVC, "nvidia,tegra20-i2c-dvc"), 42 COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"), 43 COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"), 44 COMPAT(NVIDIA_TEGRA20_KBC, "nvidia,tegra20-kbc"), 45 COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"), 46 COMPAT(NVIDIA_TEGRA20_PWM, "nvidia,tegra20-pwm"), 47 COMPAT(NVIDIA_TEGRA20_DC, "nvidia,tegra20-dc"), 48 COMPAT(SMSC_LAN9215, "smsc,lan9215"), 49 COMPAT(SAMSUNG_EXYNOS5_SROMC, "samsung,exynos-sromc"), 50 }; 51 52 const char *fdtdec_get_compatible(enum fdt_compat_id id) 53 { 54 /* We allow reading of the 'unknown' ID for testing purposes */ 55 assert(id >= 0 && id < COMPAT_COUNT); 56 return compat_names[id]; 57 } 58 59 fdt_addr_t fdtdec_get_addr(const void *blob, int node, 60 const char *prop_name) 61 { 62 const fdt_addr_t *cell; 63 int len; 64 65 debug("%s: %s: ", __func__, prop_name); 66 cell = fdt_getprop(blob, node, prop_name, &len); 67 if (cell && (len == sizeof(fdt_addr_t) || 68 len == sizeof(fdt_addr_t) * 2)) { 69 fdt_addr_t addr = fdt_addr_to_cpu(*cell); 70 71 debug("%p\n", (void *)addr); 72 return addr; 73 } 74 debug("(not found)\n"); 75 return FDT_ADDR_T_NONE; 76 } 77 78 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name, 79 s32 default_val) 80 { 81 const s32 *cell; 82 int len; 83 84 debug("%s: %s: ", __func__, prop_name); 85 cell = fdt_getprop(blob, node, prop_name, &len); 86 if (cell && len >= sizeof(s32)) { 87 s32 val = fdt32_to_cpu(cell[0]); 88 89 debug("%#x (%d)\n", val, val); 90 return val; 91 } 92 debug("(not found)\n"); 93 return default_val; 94 } 95 96 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name, 97 uint64_t default_val) 98 { 99 const uint64_t *cell64; 100 int length; 101 102 cell64 = fdt_getprop(blob, node, prop_name, &length); 103 if (!cell64 || length < sizeof(*cell64)) 104 return default_val; 105 106 return fdt64_to_cpu(*cell64); 107 } 108 109 int fdtdec_get_is_enabled(const void *blob, int node) 110 { 111 const char *cell; 112 113 /* 114 * It should say "okay", so only allow that. Some fdts use "ok" but 115 * this is a bug. Please fix your device tree source file. See here 116 * for discussion: 117 * 118 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html 119 */ 120 cell = fdt_getprop(blob, node, "status", NULL); 121 if (cell) 122 return 0 == strcmp(cell, "okay"); 123 return 1; 124 } 125 126 enum fdt_compat_id fdtdec_lookup(const void *blob, int node) 127 { 128 enum fdt_compat_id id; 129 130 /* Search our drivers */ 131 for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++) 132 if (0 == fdt_node_check_compatible(blob, node, 133 compat_names[id])) 134 return id; 135 return COMPAT_UNKNOWN; 136 } 137 138 int fdtdec_next_compatible(const void *blob, int node, 139 enum fdt_compat_id id) 140 { 141 return fdt_node_offset_by_compatible(blob, node, compat_names[id]); 142 } 143 144 int fdtdec_next_compatible_subnode(const void *blob, int node, 145 enum fdt_compat_id id, int *depthp) 146 { 147 do { 148 node = fdt_next_node(blob, node, depthp); 149 } while (*depthp > 1); 150 151 /* If this is a direct subnode, and compatible, return it */ 152 if (*depthp == 1 && 0 == fdt_node_check_compatible( 153 blob, node, compat_names[id])) 154 return node; 155 156 return -FDT_ERR_NOTFOUND; 157 } 158 159 int fdtdec_next_alias(const void *blob, const char *name, 160 enum fdt_compat_id id, int *upto) 161 { 162 #define MAX_STR_LEN 20 163 char str[MAX_STR_LEN + 20]; 164 int node, err; 165 166 /* snprintf() is not available */ 167 assert(strlen(name) < MAX_STR_LEN); 168 sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto); 169 node = fdt_path_offset(blob, str); 170 if (node < 0) 171 return node; 172 err = fdt_node_check_compatible(blob, node, compat_names[id]); 173 if (err < 0) 174 return err; 175 if (err) 176 return -FDT_ERR_NOTFOUND; 177 (*upto)++; 178 return node; 179 } 180 181 int fdtdec_find_aliases_for_id(const void *blob, const char *name, 182 enum fdt_compat_id id, int *node_list, int maxcount) 183 { 184 memset(node_list, '\0', sizeof(*node_list) * maxcount); 185 186 return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount); 187 } 188 189 /* TODO: Can we tighten this code up a little? */ 190 int fdtdec_add_aliases_for_id(const void *blob, const char *name, 191 enum fdt_compat_id id, int *node_list, int maxcount) 192 { 193 int name_len = strlen(name); 194 int nodes[maxcount]; 195 int num_found = 0; 196 int offset, node; 197 int alias_node; 198 int count; 199 int i, j; 200 201 /* find the alias node if present */ 202 alias_node = fdt_path_offset(blob, "/aliases"); 203 204 /* 205 * start with nothing, and we can assume that the root node can't 206 * match 207 */ 208 memset(nodes, '\0', sizeof(nodes)); 209 210 /* First find all the compatible nodes */ 211 for (node = count = 0; node >= 0 && count < maxcount;) { 212 node = fdtdec_next_compatible(blob, node, id); 213 if (node >= 0) 214 nodes[count++] = node; 215 } 216 if (node >= 0) 217 debug("%s: warning: maxcount exceeded with alias '%s'\n", 218 __func__, name); 219 220 /* Now find all the aliases */ 221 for (offset = fdt_first_property_offset(blob, alias_node); 222 offset > 0; 223 offset = fdt_next_property_offset(blob, offset)) { 224 const struct fdt_property *prop; 225 const char *path; 226 int number; 227 int found; 228 229 node = 0; 230 prop = fdt_get_property_by_offset(blob, offset, NULL); 231 path = fdt_string(blob, fdt32_to_cpu(prop->nameoff)); 232 if (prop->len && 0 == strncmp(path, name, name_len)) 233 node = fdt_path_offset(blob, prop->data); 234 if (node <= 0) 235 continue; 236 237 /* Get the alias number */ 238 number = simple_strtoul(path + name_len, NULL, 10); 239 if (number < 0 || number >= maxcount) { 240 debug("%s: warning: alias '%s' is out of range\n", 241 __func__, path); 242 continue; 243 } 244 245 /* Make sure the node we found is actually in our list! */ 246 found = -1; 247 for (j = 0; j < count; j++) 248 if (nodes[j] == node) { 249 found = j; 250 break; 251 } 252 253 if (found == -1) { 254 debug("%s: warning: alias '%s' points to a node " 255 "'%s' that is missing or is not compatible " 256 " with '%s'\n", __func__, path, 257 fdt_get_name(blob, node, NULL), 258 compat_names[id]); 259 continue; 260 } 261 262 /* 263 * Add this node to our list in the right place, and mark 264 * it as done. 265 */ 266 if (fdtdec_get_is_enabled(blob, node)) { 267 if (node_list[number]) { 268 debug("%s: warning: alias '%s' requires that " 269 "a node be placed in the list in a " 270 "position which is already filled by " 271 "node '%s'\n", __func__, path, 272 fdt_get_name(blob, node, NULL)); 273 continue; 274 } 275 node_list[number] = node; 276 if (number >= num_found) 277 num_found = number + 1; 278 } 279 nodes[found] = 0; 280 } 281 282 /* Add any nodes not mentioned by an alias */ 283 for (i = j = 0; i < maxcount; i++) { 284 if (!node_list[i]) { 285 for (; j < maxcount; j++) 286 if (nodes[j] && 287 fdtdec_get_is_enabled(blob, nodes[j])) 288 break; 289 290 /* Have we run out of nodes to add? */ 291 if (j == maxcount) 292 break; 293 294 assert(!node_list[i]); 295 node_list[i] = nodes[j++]; 296 if (i >= num_found) 297 num_found = i + 1; 298 } 299 } 300 301 return num_found; 302 } 303 304 int fdtdec_check_fdt(void) 305 { 306 /* 307 * We must have an FDT, but we cannot panic() yet since the console 308 * is not ready. So for now, just assert(). Boards which need an early 309 * FDT (prior to console ready) will need to make their own 310 * arrangements and do their own checks. 311 */ 312 assert(!fdtdec_prepare_fdt()); 313 return 0; 314 } 315 316 /* 317 * This function is a little odd in that it accesses global data. At some 318 * point if the architecture board.c files merge this will make more sense. 319 * Even now, it is common code. 320 */ 321 int fdtdec_prepare_fdt(void) 322 { 323 if (((uintptr_t)gd->fdt_blob & 3) || fdt_check_header(gd->fdt_blob)) { 324 printf("No valid FDT found - please append one to U-Boot " 325 "binary, use u-boot-dtb.bin or define " 326 "CONFIG_OF_EMBED\n"); 327 return -1; 328 } 329 return 0; 330 } 331 332 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name) 333 { 334 const u32 *phandle; 335 int lookup; 336 337 debug("%s: %s\n", __func__, prop_name); 338 phandle = fdt_getprop(blob, node, prop_name, NULL); 339 if (!phandle) 340 return -FDT_ERR_NOTFOUND; 341 342 lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle)); 343 return lookup; 344 } 345 346 /** 347 * Look up a property in a node and check that it has a minimum length. 348 * 349 * @param blob FDT blob 350 * @param node node to examine 351 * @param prop_name name of property to find 352 * @param min_len minimum property length in bytes 353 * @param err 0 if ok, or -FDT_ERR_NOTFOUND if the property is not 354 found, or -FDT_ERR_BADLAYOUT if not enough data 355 * @return pointer to cell, which is only valid if err == 0 356 */ 357 static const void *get_prop_check_min_len(const void *blob, int node, 358 const char *prop_name, int min_len, int *err) 359 { 360 const void *cell; 361 int len; 362 363 debug("%s: %s\n", __func__, prop_name); 364 cell = fdt_getprop(blob, node, prop_name, &len); 365 if (!cell) 366 *err = -FDT_ERR_NOTFOUND; 367 else if (len < min_len) 368 *err = -FDT_ERR_BADLAYOUT; 369 else 370 *err = 0; 371 return cell; 372 } 373 374 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name, 375 u32 *array, int count) 376 { 377 const u32 *cell; 378 int i, err = 0; 379 380 debug("%s: %s\n", __func__, prop_name); 381 cell = get_prop_check_min_len(blob, node, prop_name, 382 sizeof(u32) * count, &err); 383 if (!err) { 384 for (i = 0; i < count; i++) 385 array[i] = fdt32_to_cpu(cell[i]); 386 } 387 return err; 388 } 389 390 const u32 *fdtdec_locate_array(const void *blob, int node, 391 const char *prop_name, int count) 392 { 393 const u32 *cell; 394 int err; 395 396 cell = get_prop_check_min_len(blob, node, prop_name, 397 sizeof(u32) * count, &err); 398 return err ? NULL : cell; 399 } 400 401 int fdtdec_get_bool(const void *blob, int node, const char *prop_name) 402 { 403 const s32 *cell; 404 int len; 405 406 debug("%s: %s\n", __func__, prop_name); 407 cell = fdt_getprop(blob, node, prop_name, &len); 408 return cell != NULL; 409 } 410 411 /** 412 * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no 413 * terminating item. 414 * 415 * @param blob FDT blob to use 416 * @param node Node to look at 417 * @param prop_name Node property name 418 * @param gpio Array of gpio elements to fill from FDT. This will be 419 * untouched if either 0 or an error is returned 420 * @param max_count Maximum number of elements allowed 421 * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would 422 * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing. 423 */ 424 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name, 425 struct fdt_gpio_state *gpio, int max_count) 426 { 427 const struct fdt_property *prop; 428 const u32 *cell; 429 const char *name; 430 int len, i; 431 432 debug("%s: %s\n", __func__, prop_name); 433 assert(max_count > 0); 434 prop = fdt_get_property(blob, node, prop_name, &len); 435 if (!prop) { 436 debug("%s: property '%s' missing\n", __func__, prop_name); 437 return -FDT_ERR_NOTFOUND; 438 } 439 440 /* We will use the name to tag the GPIO */ 441 name = fdt_string(blob, fdt32_to_cpu(prop->nameoff)); 442 cell = (u32 *)prop->data; 443 len /= sizeof(u32) * 3; /* 3 cells per GPIO record */ 444 if (len > max_count) { 445 debug(" %s: too many GPIOs / cells for " 446 "property '%s'\n", __func__, prop_name); 447 return -FDT_ERR_BADLAYOUT; 448 } 449 450 /* Read out the GPIO data from the cells */ 451 for (i = 0; i < len; i++, cell += 3) { 452 gpio[i].gpio = fdt32_to_cpu(cell[1]); 453 gpio[i].flags = fdt32_to_cpu(cell[2]); 454 gpio[i].name = name; 455 } 456 457 return len; 458 } 459 460 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name, 461 struct fdt_gpio_state *gpio) 462 { 463 int err; 464 465 debug("%s: %s\n", __func__, prop_name); 466 gpio->gpio = FDT_GPIO_NONE; 467 gpio->name = NULL; 468 err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1); 469 return err == 1 ? 0 : err; 470 } 471 472 int fdtdec_get_gpio(struct fdt_gpio_state *gpio) 473 { 474 int val; 475 476 if (!fdt_gpio_isvalid(gpio)) 477 return -1; 478 479 val = gpio_get_value(gpio->gpio); 480 return gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val; 481 } 482 483 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val) 484 { 485 if (!fdt_gpio_isvalid(gpio)) 486 return -1; 487 488 val = gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val; 489 return gpio_set_value(gpio->gpio, val); 490 } 491 492 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio) 493 { 494 /* 495 * Return success if there is no GPIO defined. This is used for 496 * optional GPIOs) 497 */ 498 if (!fdt_gpio_isvalid(gpio)) 499 return 0; 500 501 if (gpio_request(gpio->gpio, gpio->name)) 502 return -1; 503 return 0; 504 } 505 506 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name, 507 u8 *array, int count) 508 { 509 const u8 *cell; 510 int err; 511 512 cell = get_prop_check_min_len(blob, node, prop_name, count, &err); 513 if (!err) 514 memcpy(array, cell, count); 515 return err; 516 } 517 518 const u8 *fdtdec_locate_byte_array(const void *blob, int node, 519 const char *prop_name, int count) 520 { 521 const u8 *cell; 522 int err; 523 524 cell = get_prop_check_min_len(blob, node, prop_name, count, &err); 525 if (err) 526 return NULL; 527 return cell; 528 } 529 530 int fdtdec_get_config_int(const void *blob, const char *prop_name, 531 int default_val) 532 { 533 int config_node; 534 535 debug("%s: %s\n", __func__, prop_name); 536 config_node = fdt_path_offset(blob, "/config"); 537 if (config_node < 0) 538 return default_val; 539 return fdtdec_get_int(blob, config_node, prop_name, default_val); 540 } 541 542 int fdtdec_get_config_bool(const void *blob, const char *prop_name) 543 { 544 int config_node; 545 const void *prop; 546 547 debug("%s: %s\n", __func__, prop_name); 548 config_node = fdt_path_offset(blob, "/config"); 549 if (config_node < 0) 550 return 0; 551 prop = fdt_get_property(blob, config_node, prop_name, NULL); 552 553 return prop != NULL; 554 } 555 556 char *fdtdec_get_config_string(const void *blob, const char *prop_name) 557 { 558 const char *nodep; 559 int nodeoffset; 560 int len; 561 562 debug("%s: %s\n", __func__, prop_name); 563 nodeoffset = fdt_path_offset(blob, "/config"); 564 if (nodeoffset < 0) 565 return NULL; 566 567 nodep = fdt_getprop(blob, nodeoffset, prop_name, &len); 568 if (!nodep) 569 return NULL; 570 571 return (char *)nodep; 572 } 573 574 int fdtdec_decode_region(const void *blob, int node, 575 const char *prop_name, void **ptrp, size_t *size) 576 { 577 const fdt_addr_t *cell; 578 int len; 579 580 debug("%s: %s\n", __func__, prop_name); 581 cell = fdt_getprop(blob, node, prop_name, &len); 582 if (!cell || (len != sizeof(fdt_addr_t) * 2)) 583 return -1; 584 585 *ptrp = (void *)fdt_addr_to_cpu(*cell); 586 *size = fdt_size_to_cpu(cell[1]); 587 debug("%s: size=%zx\n", __func__, *size); 588 return 0; 589 } 590