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 COMPAT(SAMSUNG_S3C2440_I2C, "samsung,s3c2440-i2c"), 51 COMPAT(SAMSUNG_EXYNOS5_SOUND, "samsung,exynos-sound"), 52 COMPAT(WOLFSON_WM8994_CODEC, "wolfson,wm8994-codec"), 53 COMPAT(SAMSUNG_EXYNOS_SPI, "samsung,exynos-spi"), 54 }; 55 56 const char *fdtdec_get_compatible(enum fdt_compat_id id) 57 { 58 /* We allow reading of the 'unknown' ID for testing purposes */ 59 assert(id >= 0 && id < COMPAT_COUNT); 60 return compat_names[id]; 61 } 62 63 fdt_addr_t fdtdec_get_addr(const void *blob, int node, 64 const char *prop_name) 65 { 66 const fdt_addr_t *cell; 67 int len; 68 69 debug("%s: %s: ", __func__, prop_name); 70 cell = fdt_getprop(blob, node, prop_name, &len); 71 if (cell && (len == sizeof(fdt_addr_t) || 72 len == sizeof(fdt_addr_t) * 2)) { 73 fdt_addr_t addr = fdt_addr_to_cpu(*cell); 74 75 debug("%p\n", (void *)addr); 76 return addr; 77 } 78 debug("(not found)\n"); 79 return FDT_ADDR_T_NONE; 80 } 81 82 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name, 83 s32 default_val) 84 { 85 const s32 *cell; 86 int len; 87 88 debug("%s: %s: ", __func__, prop_name); 89 cell = fdt_getprop(blob, node, prop_name, &len); 90 if (cell && len >= sizeof(s32)) { 91 s32 val = fdt32_to_cpu(cell[0]); 92 93 debug("%#x (%d)\n", val, val); 94 return val; 95 } 96 debug("(not found)\n"); 97 return default_val; 98 } 99 100 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name, 101 uint64_t default_val) 102 { 103 const uint64_t *cell64; 104 int length; 105 106 cell64 = fdt_getprop(blob, node, prop_name, &length); 107 if (!cell64 || length < sizeof(*cell64)) 108 return default_val; 109 110 return fdt64_to_cpu(*cell64); 111 } 112 113 int fdtdec_get_is_enabled(const void *blob, int node) 114 { 115 const char *cell; 116 117 /* 118 * It should say "okay", so only allow that. Some fdts use "ok" but 119 * this is a bug. Please fix your device tree source file. See here 120 * for discussion: 121 * 122 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html 123 */ 124 cell = fdt_getprop(blob, node, "status", NULL); 125 if (cell) 126 return 0 == strcmp(cell, "okay"); 127 return 1; 128 } 129 130 enum fdt_compat_id fdtdec_lookup(const void *blob, int node) 131 { 132 enum fdt_compat_id id; 133 134 /* Search our drivers */ 135 for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++) 136 if (0 == fdt_node_check_compatible(blob, node, 137 compat_names[id])) 138 return id; 139 return COMPAT_UNKNOWN; 140 } 141 142 int fdtdec_next_compatible(const void *blob, int node, 143 enum fdt_compat_id id) 144 { 145 return fdt_node_offset_by_compatible(blob, node, compat_names[id]); 146 } 147 148 int fdtdec_next_compatible_subnode(const void *blob, int node, 149 enum fdt_compat_id id, int *depthp) 150 { 151 do { 152 node = fdt_next_node(blob, node, depthp); 153 } while (*depthp > 1); 154 155 /* If this is a direct subnode, and compatible, return it */ 156 if (*depthp == 1 && 0 == fdt_node_check_compatible( 157 blob, node, compat_names[id])) 158 return node; 159 160 return -FDT_ERR_NOTFOUND; 161 } 162 163 int fdtdec_next_alias(const void *blob, const char *name, 164 enum fdt_compat_id id, int *upto) 165 { 166 #define MAX_STR_LEN 20 167 char str[MAX_STR_LEN + 20]; 168 int node, err; 169 170 /* snprintf() is not available */ 171 assert(strlen(name) < MAX_STR_LEN); 172 sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto); 173 node = fdt_path_offset(blob, str); 174 if (node < 0) 175 return node; 176 err = fdt_node_check_compatible(blob, node, compat_names[id]); 177 if (err < 0) 178 return err; 179 if (err) 180 return -FDT_ERR_NOTFOUND; 181 (*upto)++; 182 return node; 183 } 184 185 int fdtdec_find_aliases_for_id(const void *blob, const char *name, 186 enum fdt_compat_id id, int *node_list, int maxcount) 187 { 188 memset(node_list, '\0', sizeof(*node_list) * maxcount); 189 190 return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount); 191 } 192 193 /* TODO: Can we tighten this code up a little? */ 194 int fdtdec_add_aliases_for_id(const void *blob, const char *name, 195 enum fdt_compat_id id, int *node_list, int maxcount) 196 { 197 int name_len = strlen(name); 198 int nodes[maxcount]; 199 int num_found = 0; 200 int offset, node; 201 int alias_node; 202 int count; 203 int i, j; 204 205 /* find the alias node if present */ 206 alias_node = fdt_path_offset(blob, "/aliases"); 207 208 /* 209 * start with nothing, and we can assume that the root node can't 210 * match 211 */ 212 memset(nodes, '\0', sizeof(nodes)); 213 214 /* First find all the compatible nodes */ 215 for (node = count = 0; node >= 0 && count < maxcount;) { 216 node = fdtdec_next_compatible(blob, node, id); 217 if (node >= 0) 218 nodes[count++] = node; 219 } 220 if (node >= 0) 221 debug("%s: warning: maxcount exceeded with alias '%s'\n", 222 __func__, name); 223 224 /* Now find all the aliases */ 225 for (offset = fdt_first_property_offset(blob, alias_node); 226 offset > 0; 227 offset = fdt_next_property_offset(blob, offset)) { 228 const struct fdt_property *prop; 229 const char *path; 230 int number; 231 int found; 232 233 node = 0; 234 prop = fdt_get_property_by_offset(blob, offset, NULL); 235 path = fdt_string(blob, fdt32_to_cpu(prop->nameoff)); 236 if (prop->len && 0 == strncmp(path, name, name_len)) 237 node = fdt_path_offset(blob, prop->data); 238 if (node <= 0) 239 continue; 240 241 /* Get the alias number */ 242 number = simple_strtoul(path + name_len, NULL, 10); 243 if (number < 0 || number >= maxcount) { 244 debug("%s: warning: alias '%s' is out of range\n", 245 __func__, path); 246 continue; 247 } 248 249 /* Make sure the node we found is actually in our list! */ 250 found = -1; 251 for (j = 0; j < count; j++) 252 if (nodes[j] == node) { 253 found = j; 254 break; 255 } 256 257 if (found == -1) { 258 debug("%s: warning: alias '%s' points to a node " 259 "'%s' that is missing or is not compatible " 260 " with '%s'\n", __func__, path, 261 fdt_get_name(blob, node, NULL), 262 compat_names[id]); 263 continue; 264 } 265 266 /* 267 * Add this node to our list in the right place, and mark 268 * it as done. 269 */ 270 if (fdtdec_get_is_enabled(blob, node)) { 271 if (node_list[number]) { 272 debug("%s: warning: alias '%s' requires that " 273 "a node be placed in the list in a " 274 "position which is already filled by " 275 "node '%s'\n", __func__, path, 276 fdt_get_name(blob, node, NULL)); 277 continue; 278 } 279 node_list[number] = node; 280 if (number >= num_found) 281 num_found = number + 1; 282 } 283 nodes[found] = 0; 284 } 285 286 /* Add any nodes not mentioned by an alias */ 287 for (i = j = 0; i < maxcount; i++) { 288 if (!node_list[i]) { 289 for (; j < maxcount; j++) 290 if (nodes[j] && 291 fdtdec_get_is_enabled(blob, nodes[j])) 292 break; 293 294 /* Have we run out of nodes to add? */ 295 if (j == maxcount) 296 break; 297 298 assert(!node_list[i]); 299 node_list[i] = nodes[j++]; 300 if (i >= num_found) 301 num_found = i + 1; 302 } 303 } 304 305 return num_found; 306 } 307 308 int fdtdec_check_fdt(void) 309 { 310 /* 311 * We must have an FDT, but we cannot panic() yet since the console 312 * is not ready. So for now, just assert(). Boards which need an early 313 * FDT (prior to console ready) will need to make their own 314 * arrangements and do their own checks. 315 */ 316 assert(!fdtdec_prepare_fdt()); 317 return 0; 318 } 319 320 /* 321 * This function is a little odd in that it accesses global data. At some 322 * point if the architecture board.c files merge this will make more sense. 323 * Even now, it is common code. 324 */ 325 int fdtdec_prepare_fdt(void) 326 { 327 if (((uintptr_t)gd->fdt_blob & 3) || fdt_check_header(gd->fdt_blob)) { 328 printf("No valid FDT found - please append one to U-Boot " 329 "binary, use u-boot-dtb.bin or define " 330 "CONFIG_OF_EMBED\n"); 331 return -1; 332 } 333 return 0; 334 } 335 336 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name) 337 { 338 const u32 *phandle; 339 int lookup; 340 341 debug("%s: %s\n", __func__, prop_name); 342 phandle = fdt_getprop(blob, node, prop_name, NULL); 343 if (!phandle) 344 return -FDT_ERR_NOTFOUND; 345 346 lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle)); 347 return lookup; 348 } 349 350 /** 351 * Look up a property in a node and check that it has a minimum length. 352 * 353 * @param blob FDT blob 354 * @param node node to examine 355 * @param prop_name name of property to find 356 * @param min_len minimum property length in bytes 357 * @param err 0 if ok, or -FDT_ERR_NOTFOUND if the property is not 358 found, or -FDT_ERR_BADLAYOUT if not enough data 359 * @return pointer to cell, which is only valid if err == 0 360 */ 361 static const void *get_prop_check_min_len(const void *blob, int node, 362 const char *prop_name, int min_len, int *err) 363 { 364 const void *cell; 365 int len; 366 367 debug("%s: %s\n", __func__, prop_name); 368 cell = fdt_getprop(blob, node, prop_name, &len); 369 if (!cell) 370 *err = -FDT_ERR_NOTFOUND; 371 else if (len < min_len) 372 *err = -FDT_ERR_BADLAYOUT; 373 else 374 *err = 0; 375 return cell; 376 } 377 378 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name, 379 u32 *array, int count) 380 { 381 const u32 *cell; 382 int i, err = 0; 383 384 debug("%s: %s\n", __func__, prop_name); 385 cell = get_prop_check_min_len(blob, node, prop_name, 386 sizeof(u32) * count, &err); 387 if (!err) { 388 for (i = 0; i < count; i++) 389 array[i] = fdt32_to_cpu(cell[i]); 390 } 391 return err; 392 } 393 394 const u32 *fdtdec_locate_array(const void *blob, int node, 395 const char *prop_name, int count) 396 { 397 const u32 *cell; 398 int err; 399 400 cell = get_prop_check_min_len(blob, node, prop_name, 401 sizeof(u32) * count, &err); 402 return err ? NULL : cell; 403 } 404 405 int fdtdec_get_bool(const void *blob, int node, const char *prop_name) 406 { 407 const s32 *cell; 408 int len; 409 410 debug("%s: %s\n", __func__, prop_name); 411 cell = fdt_getprop(blob, node, prop_name, &len); 412 return cell != NULL; 413 } 414 415 /** 416 * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no 417 * terminating item. 418 * 419 * @param blob FDT blob to use 420 * @param node Node to look at 421 * @param prop_name Node property name 422 * @param gpio Array of gpio elements to fill from FDT. This will be 423 * untouched if either 0 or an error is returned 424 * @param max_count Maximum number of elements allowed 425 * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would 426 * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing. 427 */ 428 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name, 429 struct fdt_gpio_state *gpio, int max_count) 430 { 431 const struct fdt_property *prop; 432 const u32 *cell; 433 const char *name; 434 int len, i; 435 436 debug("%s: %s\n", __func__, prop_name); 437 assert(max_count > 0); 438 prop = fdt_get_property(blob, node, prop_name, &len); 439 if (!prop) { 440 debug("%s: property '%s' missing\n", __func__, prop_name); 441 return -FDT_ERR_NOTFOUND; 442 } 443 444 /* We will use the name to tag the GPIO */ 445 name = fdt_string(blob, fdt32_to_cpu(prop->nameoff)); 446 cell = (u32 *)prop->data; 447 len /= sizeof(u32) * 3; /* 3 cells per GPIO record */ 448 if (len > max_count) { 449 debug(" %s: too many GPIOs / cells for " 450 "property '%s'\n", __func__, prop_name); 451 return -FDT_ERR_BADLAYOUT; 452 } 453 454 /* Read out the GPIO data from the cells */ 455 for (i = 0; i < len; i++, cell += 3) { 456 gpio[i].gpio = fdt32_to_cpu(cell[1]); 457 gpio[i].flags = fdt32_to_cpu(cell[2]); 458 gpio[i].name = name; 459 } 460 461 return len; 462 } 463 464 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name, 465 struct fdt_gpio_state *gpio) 466 { 467 int err; 468 469 debug("%s: %s\n", __func__, prop_name); 470 gpio->gpio = FDT_GPIO_NONE; 471 gpio->name = NULL; 472 err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1); 473 return err == 1 ? 0 : err; 474 } 475 476 int fdtdec_get_gpio(struct fdt_gpio_state *gpio) 477 { 478 int val; 479 480 if (!fdt_gpio_isvalid(gpio)) 481 return -1; 482 483 val = gpio_get_value(gpio->gpio); 484 return gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val; 485 } 486 487 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val) 488 { 489 if (!fdt_gpio_isvalid(gpio)) 490 return -1; 491 492 val = gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val; 493 return gpio_set_value(gpio->gpio, val); 494 } 495 496 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio) 497 { 498 /* 499 * Return success if there is no GPIO defined. This is used for 500 * optional GPIOs) 501 */ 502 if (!fdt_gpio_isvalid(gpio)) 503 return 0; 504 505 if (gpio_request(gpio->gpio, gpio->name)) 506 return -1; 507 return 0; 508 } 509 510 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name, 511 u8 *array, int count) 512 { 513 const u8 *cell; 514 int err; 515 516 cell = get_prop_check_min_len(blob, node, prop_name, count, &err); 517 if (!err) 518 memcpy(array, cell, count); 519 return err; 520 } 521 522 const u8 *fdtdec_locate_byte_array(const void *blob, int node, 523 const char *prop_name, int count) 524 { 525 const u8 *cell; 526 int err; 527 528 cell = get_prop_check_min_len(blob, node, prop_name, count, &err); 529 if (err) 530 return NULL; 531 return cell; 532 } 533 534 int fdtdec_get_config_int(const void *blob, const char *prop_name, 535 int default_val) 536 { 537 int config_node; 538 539 debug("%s: %s\n", __func__, prop_name); 540 config_node = fdt_path_offset(blob, "/config"); 541 if (config_node < 0) 542 return default_val; 543 return fdtdec_get_int(blob, config_node, prop_name, default_val); 544 } 545 546 int fdtdec_get_config_bool(const void *blob, const char *prop_name) 547 { 548 int config_node; 549 const void *prop; 550 551 debug("%s: %s\n", __func__, prop_name); 552 config_node = fdt_path_offset(blob, "/config"); 553 if (config_node < 0) 554 return 0; 555 prop = fdt_get_property(blob, config_node, prop_name, NULL); 556 557 return prop != NULL; 558 } 559 560 char *fdtdec_get_config_string(const void *blob, const char *prop_name) 561 { 562 const char *nodep; 563 int nodeoffset; 564 int len; 565 566 debug("%s: %s\n", __func__, prop_name); 567 nodeoffset = fdt_path_offset(blob, "/config"); 568 if (nodeoffset < 0) 569 return NULL; 570 571 nodep = fdt_getprop(blob, nodeoffset, prop_name, &len); 572 if (!nodep) 573 return NULL; 574 575 return (char *)nodep; 576 } 577 578 int fdtdec_decode_region(const void *blob, int node, 579 const char *prop_name, void **ptrp, size_t *size) 580 { 581 const fdt_addr_t *cell; 582 int len; 583 584 debug("%s: %s\n", __func__, prop_name); 585 cell = fdt_getprop(blob, node, prop_name, &len); 586 if (!cell || (len != sizeof(fdt_addr_t) * 2)) 587 return -1; 588 589 *ptrp = (void *)fdt_addr_to_cpu(*cell); 590 *size = fdt_size_to_cpu(cell[1]); 591 debug("%s: size=%zx\n", __func__, *size); 592 return 0; 593 } 594