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