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(SAMSUNG_EXYNOS_FIMD, "samsung,exynos-fimd"),
  64         COMPAT(SAMSUNG_EXYNOS5_DP, "samsung,exynos5-dp"),
  65         COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686_pmic"),
  66         COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
  67         COMPAT(MAXIM_98095_CODEC, "maxim,max98095-codec"),
  68         COMPAT(INFINEON_SLB9635_TPM, "infineon,slb9635-tpm"),
  69 };
  70
  71 const char *fdtdec_get_compatible(enum fdt_compat_id id)
  72 {
  73         /* We allow reading of the 'unknown' ID for testing purposes */
  74         assert(id >= 0 && id < COMPAT_COUNT);
  75         return compat_names[id];
  76 }
  77
  78 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
  79                 const char *prop_name, fdt_size_t *sizep)
  80 {
  81         const fdt_addr_t *cell;
  82         int len;
  83
  84         debug("%s: %s: ", __func__, prop_name);
  85         cell = fdt_getprop(blob, node, prop_name, &len);
  86         if (cell && ((!sizep && len == sizeof(fdt_addr_t)) ||
  87                      len == sizeof(fdt_addr_t) * 2)) {
  88                 fdt_addr_t addr = fdt_addr_to_cpu(*cell);
  89                 if (sizep) {
  90                         const fdt_size_t *size;
  91
  92                         size = (fdt_size_t *)((char *)cell +
  93                                         sizeof(fdt_addr_t));
  94                         *sizep = fdt_size_to_cpu(*size);
  95                         debug("addr=%p, size=%p\n", (void *)addr,
  96                               (void *)*sizep);
  97                 } else {
  98                         debug("%p\n", (void *)addr);
  99                 }
 100                 return addr;
 101         }
 102         debug("(not found)\n");
 103         return FDT_ADDR_T_NONE;
 104 }
 105
 106 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
 107                 const char *prop_name)
 108 {
 109         return fdtdec_get_addr_size(blob, node, prop_name, NULL);
 110 }
 111
 112 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
 113                 s32 default_val)
 114 {
 115         const s32 *cell;
 116         int len;
 117
 118         debug("%s: %s: ", __func__, prop_name);
 119         cell = fdt_getprop(blob, node, prop_name, &len);
 120         if (cell && len >= sizeof(s32)) {
 121                 s32 val = fdt32_to_cpu(cell[0]);
 122
 123                 debug("%#x (%d)\n", val, val);
 124                 return val;
 125         }
 126         debug("(not found)\n");
 127         return default_val;
 128 }
 129
 130 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
 131                 uint64_t default_val)
 132 {
 133         const uint64_t *cell64;
 134         int length;
 135
 136         cell64 = fdt_getprop(blob, node, prop_name, &length);
 137         if (!cell64 || length < sizeof(*cell64))
 138                 return default_val;
 139
 140         return fdt64_to_cpu(*cell64);
 141 }
 142
 143 int fdtdec_get_is_enabled(const void *blob, int node)
 144 {
 145         const char *cell;
 146
 147         /*
 148          * It should say "okay", so only allow that. Some fdts use "ok" but
 149          * this is a bug. Please fix your device tree source file. See here
 150          * for discussion:
 151          *
 152          * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
 153          */
 154         cell = fdt_getprop(blob, node, "status", NULL);
 155         if (cell)
 156                 return 0 == strcmp(cell, "okay");
 157         return 1;
 158 }
 159
 160 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
 161 {
 162         enum fdt_compat_id id;
 163
 164         /* Search our drivers */
 165         for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
 166                 if (0 == fdt_node_check_compatible(blob, node,
 167                                 compat_names[id]))
 168                         return id;
 169         return COMPAT_UNKNOWN;
 170 }
 171
 172 int fdtdec_next_compatible(const void *blob, int node,
 173                 enum fdt_compat_id id)
 174 {
 175         return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
 176 }
 177
 178 int fdtdec_next_compatible_subnode(const void *blob, int node,
 179                 enum fdt_compat_id id, int *depthp)
 180 {
 181         do {
 182                 node = fdt_next_node(blob, node, depthp);
 183         } while (*depthp > 1);
 184
 185         /* If this is a direct subnode, and compatible, return it */
 186         if (*depthp == 1 && 0 == fdt_node_check_compatible(
 187                                                 blob, node, compat_names[id]))
 188                 return node;
 189
 190         return -FDT_ERR_NOTFOUND;
 191 }
 192
 193 int fdtdec_next_alias(const void *blob, const char *name,
 194                 enum fdt_compat_id id, int *upto)
 195 {
 196 #define MAX_STR_LEN 20
 197         char str[MAX_STR_LEN + 20];
 198         int node, err;
 199
 200         /* snprintf() is not available */
 201         assert(strlen(name) < MAX_STR_LEN);
 202         sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
 203         node = fdt_path_offset(blob, str);
 204         if (node < 0)
 205                 return node;
 206         err = fdt_node_check_compatible(blob, node, compat_names[id]);
 207         if (err < 0)
 208                 return err;
 209         if (err)
 210                 return -FDT_ERR_NOTFOUND;
 211         (*upto)++;
 212         return node;
 213 }
 214
 215 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
 216                         enum fdt_compat_id id, int *node_list, int maxcount)
 217 {
 218         memset(node_list, '\0', sizeof(*node_list) * maxcount);
 219
 220         return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
 221 }
 222
 223 /* TODO: Can we tighten this code up a little? */
 224 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
 225                         enum fdt_compat_id id, int *node_list, int maxcount)
 226 {
 227         int name_len = strlen(name);
 228         int nodes[maxcount];
 229         int num_found = 0;
 230         int offset, node;
 231         int alias_node;
 232         int count;
 233         int i, j;
 234
 235         /* find the alias node if present */
 236         alias_node = fdt_path_offset(blob, "/aliases");
 237
 238         /*
 239          * start with nothing, and we can assume that the root node can't
 240          * match
 241          */
 242         memset(nodes, '\0', sizeof(nodes));
 243
 244         /* First find all the compatible nodes */
 245         for (node = count = 0; node >= 0 && count < maxcount;) {
 246                 node = fdtdec_next_compatible(blob, node, id);
 247                 if (node >= 0)
 248                         nodes[count++] = node;
 249         }
 250         if (node >= 0)
 251                 debug("%s: warning: maxcount exceeded with alias '%s'\n",
 252                        __func__, name);
 253
 254         /* Now find all the aliases */
 255         for (offset = fdt_first_property_offset(blob, alias_node);
 256                         offset > 0;
 257                         offset = fdt_next_property_offset(blob, offset)) {
 258                 const struct fdt_property *prop;
 259                 const char *path;
 260                 int number;
 261                 int found;
 262
 263                 node = 0;
 264                 prop = fdt_get_property_by_offset(blob, offset, NULL);
 265                 path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
 266                 if (prop->len && 0 == strncmp(path, name, name_len))
 267                         node = fdt_path_offset(blob, prop->data);
 268                 if (node <= 0)
 269                         continue;
 270
 271                 /* Get the alias number */
 272                 number = simple_strtoul(path + name_len, NULL, 10);
 273                 if (number < 0 || number >= maxcount) {
 274                         debug("%s: warning: alias '%s' is out of range\n",
 275                                __func__, path);
 276                         continue;
 277                 }
 278
 279                 /* Make sure the node we found is actually in our list! */
 280                 found = -1;
 281                 for (j = 0; j < count; j++)
 282                         if (nodes[j] == node) {
 283                                 found = j;
 284                                 break;
 285                         }
 286
 287                 if (found == -1) {
 288                         debug("%s: warning: alias '%s' points to a node "
 289                                 "'%s' that is missing or is not compatible "
 290                                 " with '%s'\n", __func__, path,
 291                                 fdt_get_name(blob, node, NULL),
 292                                compat_names[id]);
 293                         continue;
 294                 }
 295
 296                 /*
 297                  * Add this node to our list in the right place, and mark
 298                  * it as done.
 299                  */
 300                 if (fdtdec_get_is_enabled(blob, node)) {
 301                         if (node_list[number]) {
 302                                 debug("%s: warning: alias '%s' requires that "
 303                                       "a node be placed in the list in a "
 304                                       "position which is already filled by "
 305                                       "node '%s'\n", __func__, path,
 306                                       fdt_get_name(blob, node, NULL));
 307                                 continue;
 308                         }
 309                         node_list[number] = node;
 310                         if (number >= num_found)
 311                                 num_found = number + 1;
 312                 }
 313                 nodes[found] = 0;
 314         }
 315
 316         /* Add any nodes not mentioned by an alias */
 317         for (i = j = 0; i < maxcount; i++) {
 318                 if (!node_list[i]) {
 319                         for (; j < maxcount; j++)
 320                                 if (nodes[j] &&
 321                                         fdtdec_get_is_enabled(blob, nodes[j]))
 322                                         break;
 323
 324                         /* Have we run out of nodes to add? */
 325                         if (j == maxcount)
 326                                 break;
 327
 328                         assert(!node_list[i]);
 329                         node_list[i] = nodes[j++];
 330                         if (i >= num_found)
 331                                 num_found = i + 1;
 332                 }
 333         }
 334
 335         return num_found;
 336 }
 337
 338 int fdtdec_check_fdt(void)
 339 {
 340         /*
 341          * We must have an FDT, but we cannot panic() yet since the console
 342          * is not ready. So for now, just assert(). Boards which need an early
 343          * FDT (prior to console ready) will need to make their own
 344          * arrangements and do their own checks.
 345          */
 346         assert(!fdtdec_prepare_fdt());
 347         return 0;
 348 }
 349
 350 /*
 351  * This function is a little odd in that it accesses global data. At some
 352  * point if the architecture board.c files merge this will make more sense.
 353  * Even now, it is common code.
 354  */
 355 int fdtdec_prepare_fdt(void)
 356 {
 357         if (((uintptr_t)gd->fdt_blob & 3) || fdt_check_header(gd->fdt_blob)) {
 358                 printf("No valid FDT found - please append one to U-Boot "
 359                         "binary, use u-boot-dtb.bin or define "
 360                         "CONFIG_OF_EMBED\n");
 361                 return -1;
 362         }
 363         return 0;
 364 }
 365
 366 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
 367 {
 368         const u32 *phandle;
 369         int lookup;
 370
 371         debug("%s: %s\n", __func__, prop_name);
 372         phandle = fdt_getprop(blob, node, prop_name, NULL);
 373         if (!phandle)
 374                 return -FDT_ERR_NOTFOUND;
 375
 376         lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
 377         return lookup;
 378 }
 379
 380 /**
 381  * Look up a property in a node and check that it has a minimum length.
 382  *
 383  * @param blob          FDT blob
 384  * @param node          node to examine
 385  * @param prop_name     name of property to find
 386  * @param min_len       minimum property length in bytes
 387  * @param err           0 if ok, or -FDT_ERR_NOTFOUND if the property is not
 388                         found, or -FDT_ERR_BADLAYOUT if not enough data
 389  * @return pointer to cell, which is only valid if err == 0
 390  */
 391 static const void *get_prop_check_min_len(const void *blob, int node,
 392                 const char *prop_name, int min_len, int *err)
 393 {
 394         const void *cell;
 395         int len;
 396
 397         debug("%s: %s\n", __func__, prop_name);
 398         cell = fdt_getprop(blob, node, prop_name, &len);
 399         if (!cell)
 400                 *err = -FDT_ERR_NOTFOUND;
 401         else if (len < min_len)
 402                 *err = -FDT_ERR_BADLAYOUT;
 403         else
 404                 *err = 0;
 405         return cell;
 406 }
 407
 408 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
 409                 u32 *array, int count)
 410 {
 411         const u32 *cell;
 412         int i, err = 0;
 413
 414         debug("%s: %s\n", __func__, prop_name);
 415         cell = get_prop_check_min_len(blob, node, prop_name,
 416                                       sizeof(u32) * count, &err);
 417         if (!err) {
 418                 for (i = 0; i < count; i++)
 419                         array[i] = fdt32_to_cpu(cell[i]);
 420         }
 421         return err;
 422 }
 423
 424 const u32 *fdtdec_locate_array(const void *blob, int node,
 425                                const char *prop_name, int count)
 426 {
 427         const u32 *cell;
 428         int err;
 429
 430         cell = get_prop_check_min_len(blob, node, prop_name,
 431                                       sizeof(u32) * count, &err);
 432         return err ? NULL : cell;
 433 }
 434
 435 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
 436 {
 437         const s32 *cell;
 438         int len;
 439
 440         debug("%s: %s\n", __func__, prop_name);
 441         cell = fdt_getprop(blob, node, prop_name, &len);
 442         return cell != NULL;
 443 }
 444
 445 /**
 446  * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
 447  * terminating item.
 448  *
 449  * @param blob          FDT blob to use
 450  * @param node          Node to look at
 451  * @param prop_name     Node property name
 452  * @param gpio          Array of gpio elements to fill from FDT. This will be
 453  *                      untouched if either 0 or an error is returned
 454  * @param max_count     Maximum number of elements allowed
 455  * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
 456  * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
 457  */
 458 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
 459                 struct fdt_gpio_state *gpio, int max_count)
 460 {
 461         const struct fdt_property *prop;
 462         const u32 *cell;
 463         const char *name;
 464         int len, i;
 465
 466         debug("%s: %s\n", __func__, prop_name);
 467         assert(max_count > 0);
 468         prop = fdt_get_property(blob, node, prop_name, &len);
 469         if (!prop) {
 470                 debug("%s: property '%s' missing\n", __func__, prop_name);
 471                 return -FDT_ERR_NOTFOUND;
 472         }
 473
 474         /* We will use the name to tag the GPIO */
 475         name = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
 476         cell = (u32 *)prop->data;
 477         len /= sizeof(u32) * 3;         /* 3 cells per GPIO record */
 478         if (len > max_count) {
 479                 debug(" %s: too many GPIOs / cells for "
 480                         "property '%s'\n", __func__, prop_name);
 481                 return -FDT_ERR_BADLAYOUT;
 482         }
 483
 484         /* Read out the GPIO data from the cells */
 485         for (i = 0; i < len; i++, cell += 3) {
 486                 gpio[i].gpio = fdt32_to_cpu(cell[1]);
 487                 gpio[i].flags = fdt32_to_cpu(cell[2]);
 488                 gpio[i].name = name;
 489         }
 490
 491         return len;
 492 }
 493
 494 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
 495                 struct fdt_gpio_state *gpio)
 496 {
 497         int err;
 498
 499         debug("%s: %s\n", __func__, prop_name);
 500         gpio->gpio = FDT_GPIO_NONE;
 501         gpio->name = NULL;
 502         err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1);
 503         return err == 1 ? 0 : err;
 504 }
 505
 506 int fdtdec_get_gpio(struct fdt_gpio_state *gpio)
 507 {
 508         int val;
 509
 510         if (!fdt_gpio_isvalid(gpio))
 511                 return -1;
 512
 513         val = gpio_get_value(gpio->gpio);
 514         return gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
 515 }
 516
 517 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val)
 518 {
 519         if (!fdt_gpio_isvalid(gpio))
 520                 return -1;
 521
 522         val = gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
 523         return gpio_set_value(gpio->gpio, val);
 524 }
 525
 526 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio)
 527 {
 528         /*
 529          * Return success if there is no GPIO defined. This is used for
 530          * optional GPIOs)
 531          */
 532         if (!fdt_gpio_isvalid(gpio))
 533                 return 0;
 534
 535         if (gpio_request(gpio->gpio, gpio->name))
 536                 return -1;
 537         return 0;
 538 }
 539
 540 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
 541                 u8 *array, int count)
 542 {
 543         const u8 *cell;
 544         int err;
 545
 546         cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
 547         if (!err)
 548                 memcpy(array, cell, count);
 549         return err;
 550 }
 551
 552 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
 553                              const char *prop_name, int count)
 554 {
 555         const u8 *cell;
 556         int err;
 557
 558         cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
 559         if (err)
 560                 return NULL;
 561         return cell;
 562 }
 563
 564 int fdtdec_get_config_int(const void *blob, const char *prop_name,
 565                 int default_val)
 566 {
 567         int config_node;
 568
 569         debug("%s: %s\n", __func__, prop_name);
 570         config_node = fdt_path_offset(blob, "/config");
 571         if (config_node < 0)
 572                 return default_val;
 573         return fdtdec_get_int(blob, config_node, prop_name, default_val);
 574 }
 575
 576 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
 577 {
 578         int config_node;
 579         const void *prop;
 580
 581         debug("%s: %s\n", __func__, prop_name);
 582         config_node = fdt_path_offset(blob, "/config");
 583         if (config_node < 0)
 584                 return 0;
 585         prop = fdt_get_property(blob, config_node, prop_name, NULL);
 586
 587         return prop != NULL;
 588 }
 589
 590 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
 591 {
 592         const char *nodep;
 593         int nodeoffset;
 594         int len;
 595
 596         debug("%s: %s\n", __func__, prop_name);
 597         nodeoffset = fdt_path_offset(blob, "/config");
 598         if (nodeoffset < 0)
 599                 return NULL;
 600
 601         nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
 602         if (!nodep)
 603                 return NULL;
 604
 605         return (char *)nodep;
 606 }
 607
 608 int fdtdec_decode_region(const void *blob, int node,
 609                 const char *prop_name, void **ptrp, size_t *size)
 610 {
 611         const fdt_addr_t *cell;
 612         int len;
 613
 614         debug("%s: %s\n", __func__, prop_name);
 615         cell = fdt_getprop(blob, node, prop_name, &len);
 616         if (!cell || (len != sizeof(fdt_addr_t) * 2))
 617                 return -1;
 618
 619         *ptrp = (void *)fdt_addr_to_cpu(*cell);
 620         *size = fdt_size_to_cpu(cell[1]);
 621         debug("%s: size=%zx\n", __func__, *size);
 622         return 0;
 623 }