lib/fdtdec.c

   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_TEGRA114_I2C, "nvidia,tegra114-i2c"),
  41         COMPAT(NVIDIA_TEGRA20_I2C, "nvidia,tegra20-i2c"),
  42         COMPAT(NVIDIA_TEGRA20_DVC, "nvidia,tegra20-i2c-dvc"),
  43         COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"),
  44         COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"),
  45         COMPAT(NVIDIA_TEGRA20_KBC, "nvidia,tegra20-kbc"),
  46         COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"),
  47         COMPAT(NVIDIA_TEGRA20_PWM, "nvidia,tegra20-pwm"),
  48         COMPAT(NVIDIA_TEGRA20_DC, "nvidia,tegra20-dc"),
  49         COMPAT(NVIDIA_TEGRA30_SDMMC, "nvidia,tegra30-sdhci"),
  50         COMPAT(NVIDIA_TEGRA20_SDMMC, "nvidia,tegra20-sdhci"),
  51         COMPAT(NVIDIA_TEGRA20_SFLASH, "nvidia,tegra20-sflash"),
  52         COMPAT(NVIDIA_TEGRA20_SLINK, "nvidia,tegra20-slink"),
  53         COMPAT(NVIDIA_TEGRA114_SPI, "nvidia,tegra114-spi"),
  54         COMPAT(SMSC_LAN9215, "smsc,lan9215"),
  55         COMPAT(SAMSUNG_EXYNOS5_SROMC, "samsung,exynos-sromc"),
  56         COMPAT(SAMSUNG_S3C2440_I2C, "samsung,s3c2440-i2c"),
  57         COMPAT(SAMSUNG_EXYNOS5_SOUND, "samsung,exynos-sound"),
  58         COMPAT(WOLFSON_WM8994_CODEC, "wolfson,wm8994-codec"),
  59         COMPAT(SAMSUNG_EXYNOS_SPI, "samsung,exynos-spi"),
  60         COMPAT(SAMSUNG_EXYNOS_EHCI, "samsung,exynos-ehci"),
  61         COMPAT(SAMSUNG_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
  62         COMPAT(SAMSUNG_EXYNOS_TMU, "samsung,exynos-tmu"),
  63         COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686_pmic"),
  64         COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
  65         COMPAT(MAXIM_98095_CODEC, "maxim,max98095-codec"),
  66 };
  67
  68 const char *fdtdec_get_compatible(enum fdt_compat_id id)
  69 {
  70         /* We allow reading of the 'unknown' ID for testing purposes */
  71         assert(id >= 0 && id < COMPAT_COUNT);
  72         return compat_names[id];
  73 }
  74
  75 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
  76                 const char *prop_name, fdt_size_t *sizep)
  77 {
  78         const fdt_addr_t *cell;
  79         int len;
  80
  81         debug("%s: %s: ", __func__, prop_name);
  82         cell = fdt_getprop(blob, node, prop_name, &len);
  83         if (cell && ((!sizep && len == sizeof(fdt_addr_t)) ||
  84                      len == sizeof(fdt_addr_t) * 2)) {
  85                 fdt_addr_t addr = fdt_addr_to_cpu(*cell);
  86                 if (sizep) {
  87                         const fdt_size_t *size;
  88
  89                         size = (fdt_size_t *)((char *)cell +
  90                                         sizeof(fdt_addr_t));
  91                         *sizep = fdt_size_to_cpu(*size);
  92                         debug("addr=%p, size=%p\n", (void *)addr,
  93                               (void *)*sizep);
  94                 } else {
  95                         debug("%p\n", (void *)addr);
  96                 }
  97                 return addr;
  98         }
  99         debug("(not found)\n");
 100         return FDT_ADDR_T_NONE;
 101 }
 102
 103 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
 104                 const char *prop_name)
 105 {
 106         return fdtdec_get_addr_size(blob, node, prop_name, NULL);
 107 }
 108
 109 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
 110                 s32 default_val)
 111 {
 112         const s32 *cell;
 113         int len;
 114
 115         debug("%s: %s: ", __func__, prop_name);
 116         cell = fdt_getprop(blob, node, prop_name, &len);
 117         if (cell && len >= sizeof(s32)) {
 118                 s32 val = fdt32_to_cpu(cell[0]);
 119
 120                 debug("%#x (%d)\n", val, val);
 121                 return val;
 122         }
 123         debug("(not found)\n");
 124         return default_val;
 125 }
 126
 127 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
 128                 uint64_t default_val)
 129 {
 130         const uint64_t *cell64;
 131         int length;
 132
 133         cell64 = fdt_getprop(blob, node, prop_name, &length);
 134         if (!cell64 || length < sizeof(*cell64))
 135                 return default_val;
 136
 137         return fdt64_to_cpu(*cell64);
 138 }
 139
 140 int fdtdec_get_is_enabled(const void *blob, int node)
 141 {
 142         const char *cell;
 143
 144         /*
 145          * It should say "okay", so only allow that. Some fdts use "ok" but
 146          * this is a bug. Please fix your device tree source file. See here
 147          * for discussion:
 148          *
 149          * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
 150          */
 151         cell = fdt_getprop(blob, node, "status", NULL);
 152         if (cell)
 153                 return 0 == strcmp(cell, "okay");
 154         return 1;
 155 }
 156
 157 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
 158 {
 159         enum fdt_compat_id id;
 160
 161         /* Search our drivers */
 162         for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
 163                 if (0 == fdt_node_check_compatible(blob, node,
 164                                 compat_names[id]))
 165                         return id;
 166         return COMPAT_UNKNOWN;
 167 }
 168
 169 int fdtdec_next_compatible(const void *blob, int node,
 170                 enum fdt_compat_id id)
 171 {
 172         return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
 173 }
 174
 175 int fdtdec_next_compatible_subnode(const void *blob, int node,
 176                 enum fdt_compat_id id, int *depthp)
 177 {
 178         do {
 179                 node = fdt_next_node(blob, node, depthp);
 180         } while (*depthp > 1);
 181
 182         /* If this is a direct subnode, and compatible, return it */
 183         if (*depthp == 1 && 0 == fdt_node_check_compatible(
 184                                                 blob, node, compat_names[id]))
 185                 return node;
 186
 187         return -FDT_ERR_NOTFOUND;
 188 }
 189
 190 int fdtdec_next_alias(const void *blob, const char *name,
 191                 enum fdt_compat_id id, int *upto)
 192 {
 193 #define MAX_STR_LEN 20
 194         char str[MAX_STR_LEN + 20];
 195         int node, err;
 196
 197         /* snprintf() is not available */
 198         assert(strlen(name) < MAX_STR_LEN);
 199         sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
 200         node = fdt_path_offset(blob, str);
 201         if (node < 0)
 202                 return node;
 203         err = fdt_node_check_compatible(blob, node, compat_names[id]);
 204         if (err < 0)
 205                 return err;
 206         if (err)
 207                 return -FDT_ERR_NOTFOUND;
 208         (*upto)++;
 209         return node;
 210 }
 211
 212 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
 213                         enum fdt_compat_id id, int *node_list, int maxcount)
 214 {
 215         memset(node_list, '\0', sizeof(*node_list) * maxcount);
 216
 217         return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
 218 }
 219
 220 /* TODO: Can we tighten this code up a little? */
 221 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
 222                         enum fdt_compat_id id, int *node_list, int maxcount)
 223 {
 224         int name_len = strlen(name);
 225         int nodes[maxcount];
 226         int num_found = 0;
 227         int offset, node;
 228         int alias_node;
 229         int count;
 230         int i, j;
 231
 232         /* find the alias node if present */
 233         alias_node = fdt_path_offset(blob, "/aliases");
 234
 235         /*
 236          * start with nothing, and we can assume that the root node can't
 237          * match
 238          */
 239         memset(nodes, '\0', sizeof(nodes));
 240
 241         /* First find all the compatible nodes */
 242         for (node = count = 0; node >= 0 && count < maxcount;) {
 243                 node = fdtdec_next_compatible(blob, node, id);
 244                 if (node >= 0)
 245                         nodes[count++] = node;
 246         }
 247         if (node >= 0)
 248                 debug("%s: warning: maxcount exceeded with alias '%s'\n",
 249                        __func__, name);
 250
 251         /* Now find all the aliases */
 252         for (offset = fdt_first_property_offset(blob, alias_node);
 253                         offset > 0;
 254                         offset = fdt_next_property_offset(blob, offset)) {
 255                 const struct fdt_property *prop;
 256                 const char *path;
 257                 int number;
 258                 int found;
 259
 260                 node = 0;
 261                 prop = fdt_get_property_by_offset(blob, offset, NULL);
 262                 path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
 263                 if (prop->len && 0 == strncmp(path, name, name_len))
 264                         node = fdt_path_offset(blob, prop->data);
 265                 if (node <= 0)
 266                         continue;
 267
 268                 /* Get the alias number */
 269                 number = simple_strtoul(path + name_len, NULL, 10);
 270                 if (number < 0 || number >= maxcount) {
 271                         debug("%s: warning: alias '%s' is out of range\n",
 272                                __func__, path);
 273                         continue;
 274                 }
 275
 276                 /* Make sure the node we found is actually in our list! */
 277                 found = -1;
 278                 for (j = 0; j < count; j++)
 279                         if (nodes[j] == node) {
 280                                 found = j;
 281                                 break;
 282                         }
 283
 284                 if (found == -1) {
 285                         debug("%s: warning: alias '%s' points to a node "
 286                                 "'%s' that is missing or is not compatible "
 287                                 " with '%s'\n", __func__, path,
 288                                 fdt_get_name(blob, node, NULL),
 289                                compat_names[id]);
 290                         continue;
 291                 }
 292
 293                 /*
 294                  * Add this node to our list in the right place, and mark
 295                  * it as done.
 296                  */
 297                 if (fdtdec_get_is_enabled(blob, node)) {
 298                         if (node_list[number]) {
 299                                 debug("%s: warning: alias '%s' requires that "
 300                                       "a node be placed in the list in a "
 301                                       "position which is already filled by "
 302                                       "node '%s'\n", __func__, path,
 303                                       fdt_get_name(blob, node, NULL));
 304                                 continue;
 305                         }
 306                         node_list[number] = node;
 307                         if (number >= num_found)
 308                                 num_found = number + 1;
 309                 }
 310                 nodes[found] = 0;
 311         }
 312
 313         /* Add any nodes not mentioned by an alias */
 314         for (i = j = 0; i < maxcount; i++) {
 315                 if (!node_list[i]) {
 316                         for (; j < maxcount; j++)
 317                                 if (nodes[j] &&
 318                                         fdtdec_get_is_enabled(blob, nodes[j]))
 319                                         break;
 320
 321                         /* Have we run out of nodes to add? */
 322                         if (j == maxcount)
 323                                 break;
 324
 325                         assert(!node_list[i]);
 326                         node_list[i] = nodes[j++];
 327                         if (i >= num_found)
 328                                 num_found = i + 1;
 329                 }
 330         }
 331
 332         return num_found;
 333 }
 334
 335 int fdtdec_check_fdt(void)
 336 {
 337         /*
 338          * We must have an FDT, but we cannot panic() yet since the console
 339          * is not ready. So for now, just assert(). Boards which need an early
 340          * FDT (prior to console ready) will need to make their own
 341          * arrangements and do their own checks.
 342          */
 343         assert(!fdtdec_prepare_fdt());
 344         return 0;
 345 }
 346
 347 /*
 348  * This function is a little odd in that it accesses global data. At some
 349  * point if the architecture board.c files merge this will make more sense.
 350  * Even now, it is common code.
 351  */
 352 int fdtdec_prepare_fdt(void)
 353 {
 354         if (((uintptr_t)gd->fdt_blob & 3) || fdt_check_header(gd->fdt_blob)) {
 355                 printf("No valid FDT found - please append one to U-Boot "
 356                         "binary, use u-boot-dtb.bin or define "
 357                         "CONFIG_OF_EMBED\n");
 358                 return -1;
 359         }
 360         return 0;
 361 }
 362
 363 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
 364 {
 365         const u32 *phandle;
 366         int lookup;
 367
 368         debug("%s: %s\n", __func__, prop_name);
 369         phandle = fdt_getprop(blob, node, prop_name, NULL);
 370         if (!phandle)
 371                 return -FDT_ERR_NOTFOUND;
 372
 373         lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
 374         return lookup;
 375 }
 376
 377 /**
 378  * Look up a property in a node and check that it has a minimum length.
 379  *
 380  * @param blob          FDT blob
 381  * @param node          node to examine
 382  * @param prop_name     name of property to find
 383  * @param min_len       minimum property length in bytes
 384  * @param err           0 if ok, or -FDT_ERR_NOTFOUND if the property is not
 385                         found, or -FDT_ERR_BADLAYOUT if not enough data
 386  * @return pointer to cell, which is only valid if err == 0
 387  */
 388 static const void *get_prop_check_min_len(const void *blob, int node,
 389                 const char *prop_name, int min_len, int *err)
 390 {
 391         const void *cell;
 392         int len;
 393
 394         debug("%s: %s\n", __func__, prop_name);
 395         cell = fdt_getprop(blob, node, prop_name, &len);
 396         if (!cell)
 397                 *err = -FDT_ERR_NOTFOUND;
 398         else if (len < min_len)
 399                 *err = -FDT_ERR_BADLAYOUT;
 400         else
 401                 *err = 0;
 402         return cell;
 403 }
 404
 405 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
 406                 u32 *array, int count)
 407 {
 408         const u32 *cell;
 409         int i, err = 0;
 410
 411         debug("%s: %s\n", __func__, prop_name);
 412         cell = get_prop_check_min_len(blob, node, prop_name,
 413                                       sizeof(u32) * count, &err);
 414         if (!err) {
 415                 for (i = 0; i < count; i++)
 416                         array[i] = fdt32_to_cpu(cell[i]);
 417         }
 418         return err;
 419 }
 420
 421 const u32 *fdtdec_locate_array(const void *blob, int node,
 422                                const char *prop_name, int count)
 423 {
 424         const u32 *cell;
 425         int err;
 426
 427         cell = get_prop_check_min_len(blob, node, prop_name,
 428                                       sizeof(u32) * count, &err);
 429         return err ? NULL : cell;
 430 }
 431
 432 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
 433 {
 434         const s32 *cell;
 435         int len;
 436
 437         debug("%s: %s\n", __func__, prop_name);
 438         cell = fdt_getprop(blob, node, prop_name, &len);
 439         return cell != NULL;
 440 }
 441
 442 /**
 443  * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
 444  * terminating item.
 445  *
 446  * @param blob          FDT blob to use
 447  * @param node          Node to look at
 448  * @param prop_name     Node property name
 449  * @param gpio          Array of gpio elements to fill from FDT. This will be
 450  *                      untouched if either 0 or an error is returned
 451  * @param max_count     Maximum number of elements allowed
 452  * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
 453  * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
 454  */
 455 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
 456                 struct fdt_gpio_state *gpio, int max_count)
 457 {
 458         const struct fdt_property *prop;
 459         const u32 *cell;
 460         const char *name;
 461         int len, i;
 462
 463         debug("%s: %s\n", __func__, prop_name);
 464         assert(max_count > 0);
 465         prop = fdt_get_property(blob, node, prop_name, &len);
 466         if (!prop) {
 467                 debug("%s: property '%s' missing\n", __func__, prop_name);
 468                 return -FDT_ERR_NOTFOUND;
 469         }
 470
 471         /* We will use the name to tag the GPIO */
 472         name = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
 473         cell = (u32 *)prop->data;
 474         len /= sizeof(u32) * 3;         /* 3 cells per GPIO record */
 475         if (len > max_count) {
 476                 debug(" %s: too many GPIOs / cells for "
 477                         "property '%s'\n", __func__, prop_name);
 478                 return -FDT_ERR_BADLAYOUT;
 479         }
 480
 481         /* Read out the GPIO data from the cells */
 482         for (i = 0; i < len; i++, cell += 3) {
 483                 gpio[i].gpio = fdt32_to_cpu(cell[1]);
 484                 gpio[i].flags = fdt32_to_cpu(cell[2]);
 485                 gpio[i].name = name;
 486         }
 487
 488         return len;
 489 }
 490
 491 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
 492                 struct fdt_gpio_state *gpio)
 493 {
 494         int err;
 495
 496         debug("%s: %s\n", __func__, prop_name);
 497         gpio->gpio = FDT_GPIO_NONE;
 498         gpio->name = NULL;
 499         err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1);
 500         return err == 1 ? 0 : err;
 501 }
 502
 503 int fdtdec_get_gpio(struct fdt_gpio_state *gpio)
 504 {
 505         int val;
 506
 507         if (!fdt_gpio_isvalid(gpio))
 508                 return -1;
 509
 510         val = gpio_get_value(gpio->gpio);
 511         return gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
 512 }
 513
 514 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val)
 515 {
 516         if (!fdt_gpio_isvalid(gpio))
 517                 return -1;
 518
 519         val = gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
 520         return gpio_set_value(gpio->gpio, val);
 521 }
 522
 523 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio)
 524 {
 525         /*
 526          * Return success if there is no GPIO defined. This is used for
 527          * optional GPIOs)
 528          */
 529         if (!fdt_gpio_isvalid(gpio))
 530                 return 0;
 531
 532         if (gpio_request(gpio->gpio, gpio->name))
 533                 return -1;
 534         return 0;
 535 }
 536
 537 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
 538                 u8 *array, int count)
 539 {
 540         const u8 *cell;
 541         int err;
 542
 543         cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
 544         if (!err)
 545                 memcpy(array, cell, count);
 546         return err;
 547 }
 548
 549 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
 550                              const char *prop_name, int count)
 551 {
 552         const u8 *cell;
 553         int err;
 554
 555         cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
 556         if (err)
 557                 return NULL;
 558         return cell;
 559 }
 560
 561 int fdtdec_get_config_int(const void *blob, const char *prop_name,
 562                 int default_val)
 563 {
 564         int config_node;
 565
 566         debug("%s: %s\n", __func__, prop_name);
 567         config_node = fdt_path_offset(blob, "/config");
 568         if (config_node < 0)
 569                 return default_val;
 570         return fdtdec_get_int(blob, config_node, prop_name, default_val);
 571 }
 572
 573 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
 574 {
 575         int config_node;
 576         const void *prop;
 577
 578         debug("%s: %s\n", __func__, prop_name);
 579         config_node = fdt_path_offset(blob, "/config");
 580         if (config_node < 0)
 581                 return 0;
 582         prop = fdt_get_property(blob, config_node, prop_name, NULL);
 583
 584         return prop != NULL;
 585 }
 586
 587 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
 588 {
 589         const char *nodep;
 590         int nodeoffset;
 591         int len;
 592
 593         debug("%s: %s\n", __func__, prop_name);
 594         nodeoffset = fdt_path_offset(blob, "/config");
 595         if (nodeoffset < 0)
 596                 return NULL;
 597
 598         nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
 599         if (!nodep)
 600                 return NULL;
 601
 602         return (char *)nodep;
 603 }
 604
 605 int fdtdec_decode_region(const void *blob, int node,
 606                 const char *prop_name, void **ptrp, size_t *size)
 607 {
 608         const fdt_addr_t *cell;
 609         int len;
 610
 611         debug("%s: %s\n", __func__, prop_name);
 612         cell = fdt_getprop(blob, node, prop_name, &len);
 613         if (!cell || (len != sizeof(fdt_addr_t) * 2))
 614                 return -1;
 615
 616         *ptrp = (void *)fdt_addr_to_cpu(*cell);
 617         *size = fdt_size_to_cpu(cell[1]);
 618         debug("%s: size=%zx\n", __func__, *size);
 619         return 0;
 620 }