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