linux/scripts/dtc/libfdt/libfdt.h
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   1/* SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause) */
   2#ifndef LIBFDT_H
   3#define LIBFDT_H
   4/*
   5 * libfdt - Flat Device Tree manipulation
   6 * Copyright (C) 2006 David Gibson, IBM Corporation.
   7 */
   8
   9#include "libfdt_env.h"
  10#include "fdt.h"
  11
  12#ifdef __cplusplus
  13extern "C" {
  14#endif
  15
  16#define FDT_FIRST_SUPPORTED_VERSION     0x02
  17#define FDT_LAST_COMPATIBLE_VERSION 0x10
  18#define FDT_LAST_SUPPORTED_VERSION      0x11
  19
  20/* Error codes: informative error codes */
  21#define FDT_ERR_NOTFOUND        1
  22        /* FDT_ERR_NOTFOUND: The requested node or property does not exist */
  23#define FDT_ERR_EXISTS          2
  24        /* FDT_ERR_EXISTS: Attempted to create a node or property which
  25         * already exists */
  26#define FDT_ERR_NOSPACE         3
  27        /* FDT_ERR_NOSPACE: Operation needed to expand the device
  28         * tree, but its buffer did not have sufficient space to
  29         * contain the expanded tree. Use fdt_open_into() to move the
  30         * device tree to a buffer with more space. */
  31
  32/* Error codes: codes for bad parameters */
  33#define FDT_ERR_BADOFFSET       4
  34        /* FDT_ERR_BADOFFSET: Function was passed a structure block
  35         * offset which is out-of-bounds, or which points to an
  36         * unsuitable part of the structure for the operation. */
  37#define FDT_ERR_BADPATH         5
  38        /* FDT_ERR_BADPATH: Function was passed a badly formatted path
  39         * (e.g. missing a leading / for a function which requires an
  40         * absolute path) */
  41#define FDT_ERR_BADPHANDLE      6
  42        /* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle.
  43         * This can be caused either by an invalid phandle property
  44         * length, or the phandle value was either 0 or -1, which are
  45         * not permitted. */
  46#define FDT_ERR_BADSTATE        7
  47        /* FDT_ERR_BADSTATE: Function was passed an incomplete device
  48         * tree created by the sequential-write functions, which is
  49         * not sufficiently complete for the requested operation. */
  50
  51/* Error codes: codes for bad device tree blobs */
  52#define FDT_ERR_TRUNCATED       8
  53        /* FDT_ERR_TRUNCATED: FDT or a sub-block is improperly
  54         * terminated (overflows, goes outside allowed bounds, or
  55         * isn't properly terminated).  */
  56#define FDT_ERR_BADMAGIC        9
  57        /* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
  58         * device tree at all - it is missing the flattened device
  59         * tree magic number. */
  60#define FDT_ERR_BADVERSION      10
  61        /* FDT_ERR_BADVERSION: Given device tree has a version which
  62         * can't be handled by the requested operation.  For
  63         * read-write functions, this may mean that fdt_open_into() is
  64         * required to convert the tree to the expected version. */
  65#define FDT_ERR_BADSTRUCTURE    11
  66        /* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt
  67         * structure block or other serious error (e.g. misnested
  68         * nodes, or subnodes preceding properties). */
  69#define FDT_ERR_BADLAYOUT       12
  70        /* FDT_ERR_BADLAYOUT: For read-write functions, the given
  71         * device tree has it's sub-blocks in an order that the
  72         * function can't handle (memory reserve map, then structure,
  73         * then strings).  Use fdt_open_into() to reorganize the tree
  74         * into a form suitable for the read-write operations. */
  75
  76/* "Can't happen" error indicating a bug in libfdt */
  77#define FDT_ERR_INTERNAL        13
  78        /* FDT_ERR_INTERNAL: libfdt has failed an internal assertion.
  79         * Should never be returned, if it is, it indicates a bug in
  80         * libfdt itself. */
  81
  82/* Errors in device tree content */
  83#define FDT_ERR_BADNCELLS       14
  84        /* FDT_ERR_BADNCELLS: Device tree has a #address-cells, #size-cells
  85         * or similar property with a bad format or value */
  86
  87#define FDT_ERR_BADVALUE        15
  88        /* FDT_ERR_BADVALUE: Device tree has a property with an unexpected
  89         * value. For example: a property expected to contain a string list
  90         * is not NUL-terminated within the length of its value. */
  91
  92#define FDT_ERR_BADOVERLAY      16
  93        /* FDT_ERR_BADOVERLAY: The device tree overlay, while
  94         * correctly structured, cannot be applied due to some
  95         * unexpected or missing value, property or node. */
  96
  97#define FDT_ERR_NOPHANDLES      17
  98        /* FDT_ERR_NOPHANDLES: The device tree doesn't have any
  99         * phandle available anymore without causing an overflow */
 100
 101#define FDT_ERR_BADFLAGS        18
 102        /* FDT_ERR_BADFLAGS: The function was passed a flags field that
 103         * contains invalid flags or an invalid combination of flags. */
 104
 105#define FDT_ERR_ALIGNMENT       19
 106        /* FDT_ERR_ALIGNMENT: The device tree base address is not 8-byte
 107         * aligned. */
 108
 109#define FDT_ERR_MAX             19
 110
 111/* constants */
 112#define FDT_MAX_PHANDLE 0xfffffffe
 113        /* Valid values for phandles range from 1 to 2^32-2. */
 114
 115/**********************************************************************/
 116/* Low-level functions (you probably don't need these)                */
 117/**********************************************************************/
 118
 119#ifndef SWIG /* This function is not useful in Python */
 120const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen);
 121#endif
 122static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
 123{
 124        return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
 125}
 126
 127uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
 128
 129/*
 130 * External helpers to access words from a device tree blob. They're built
 131 * to work even with unaligned pointers on platforms (such as ARMv5) that don't
 132 * like unaligned loads and stores.
 133 */
 134static inline uint32_t fdt32_ld(const fdt32_t *p)
 135{
 136        const uint8_t *bp = (const uint8_t *)p;
 137
 138        return ((uint32_t)bp[0] << 24)
 139                | ((uint32_t)bp[1] << 16)
 140                | ((uint32_t)bp[2] << 8)
 141                | bp[3];
 142}
 143
 144static inline void fdt32_st(void *property, uint32_t value)
 145{
 146        uint8_t *bp = (uint8_t *)property;
 147
 148        bp[0] = value >> 24;
 149        bp[1] = (value >> 16) & 0xff;
 150        bp[2] = (value >> 8) & 0xff;
 151        bp[3] = value & 0xff;
 152}
 153
 154static inline uint64_t fdt64_ld(const fdt64_t *p)
 155{
 156        const uint8_t *bp = (const uint8_t *)p;
 157
 158        return ((uint64_t)bp[0] << 56)
 159                | ((uint64_t)bp[1] << 48)
 160                | ((uint64_t)bp[2] << 40)
 161                | ((uint64_t)bp[3] << 32)
 162                | ((uint64_t)bp[4] << 24)
 163                | ((uint64_t)bp[5] << 16)
 164                | ((uint64_t)bp[6] << 8)
 165                | bp[7];
 166}
 167
 168static inline void fdt64_st(void *property, uint64_t value)
 169{
 170        uint8_t *bp = (uint8_t *)property;
 171
 172        bp[0] = value >> 56;
 173        bp[1] = (value >> 48) & 0xff;
 174        bp[2] = (value >> 40) & 0xff;
 175        bp[3] = (value >> 32) & 0xff;
 176        bp[4] = (value >> 24) & 0xff;
 177        bp[5] = (value >> 16) & 0xff;
 178        bp[6] = (value >> 8) & 0xff;
 179        bp[7] = value & 0xff;
 180}
 181
 182/**********************************************************************/
 183/* Traversal functions                                                */
 184/**********************************************************************/
 185
 186int fdt_next_node(const void *fdt, int offset, int *depth);
 187
 188/**
 189 * fdt_first_subnode() - get offset of first direct subnode
 190 * @fdt:        FDT blob
 191 * @offset:     Offset of node to check
 192 *
 193 * Return: offset of first subnode, or -FDT_ERR_NOTFOUND if there is none
 194 */
 195int fdt_first_subnode(const void *fdt, int offset);
 196
 197/**
 198 * fdt_next_subnode() - get offset of next direct subnode
 199 * @fdt:        FDT blob
 200 * @offset:     Offset of previous subnode
 201 *
 202 * After first calling fdt_first_subnode(), call this function repeatedly to
 203 * get direct subnodes of a parent node.
 204 *
 205 * Return: offset of next subnode, or -FDT_ERR_NOTFOUND if there are no more
 206 *         subnodes
 207 */
 208int fdt_next_subnode(const void *fdt, int offset);
 209
 210/**
 211 * fdt_for_each_subnode - iterate over all subnodes of a parent
 212 *
 213 * @node:       child node (int, lvalue)
 214 * @fdt:        FDT blob (const void *)
 215 * @parent:     parent node (int)
 216 *
 217 * This is actually a wrapper around a for loop and would be used like so:
 218 *
 219 *      fdt_for_each_subnode(node, fdt, parent) {
 220 *              Use node
 221 *              ...
 222 *      }
 223 *
 224 *      if ((node < 0) && (node != -FDT_ERR_NOTFOUND)) {
 225 *              Error handling
 226 *      }
 227 *
 228 * Note that this is implemented as a macro and @node is used as
 229 * iterator in the loop. The parent variable be constant or even a
 230 * literal.
 231 */
 232#define fdt_for_each_subnode(node, fdt, parent)         \
 233        for (node = fdt_first_subnode(fdt, parent);     \
 234             node >= 0;                                 \
 235             node = fdt_next_subnode(fdt, node))
 236
 237/**********************************************************************/
 238/* General functions                                                  */
 239/**********************************************************************/
 240#define fdt_get_header(fdt, field) \
 241        (fdt32_ld(&((const struct fdt_header *)(fdt))->field))
 242#define fdt_magic(fdt)                  (fdt_get_header(fdt, magic))
 243#define fdt_totalsize(fdt)              (fdt_get_header(fdt, totalsize))
 244#define fdt_off_dt_struct(fdt)          (fdt_get_header(fdt, off_dt_struct))
 245#define fdt_off_dt_strings(fdt)         (fdt_get_header(fdt, off_dt_strings))
 246#define fdt_off_mem_rsvmap(fdt)         (fdt_get_header(fdt, off_mem_rsvmap))
 247#define fdt_version(fdt)                (fdt_get_header(fdt, version))
 248#define fdt_last_comp_version(fdt)      (fdt_get_header(fdt, last_comp_version))
 249#define fdt_boot_cpuid_phys(fdt)        (fdt_get_header(fdt, boot_cpuid_phys))
 250#define fdt_size_dt_strings(fdt)        (fdt_get_header(fdt, size_dt_strings))
 251#define fdt_size_dt_struct(fdt)         (fdt_get_header(fdt, size_dt_struct))
 252
 253#define fdt_set_hdr_(name) \
 254        static inline void fdt_set_##name(void *fdt, uint32_t val) \
 255        { \
 256                struct fdt_header *fdth = (struct fdt_header *)fdt; \
 257                fdth->name = cpu_to_fdt32(val); \
 258        }
 259fdt_set_hdr_(magic);
 260fdt_set_hdr_(totalsize);
 261fdt_set_hdr_(off_dt_struct);
 262fdt_set_hdr_(off_dt_strings);
 263fdt_set_hdr_(off_mem_rsvmap);
 264fdt_set_hdr_(version);
 265fdt_set_hdr_(last_comp_version);
 266fdt_set_hdr_(boot_cpuid_phys);
 267fdt_set_hdr_(size_dt_strings);
 268fdt_set_hdr_(size_dt_struct);
 269#undef fdt_set_hdr_
 270
 271/**
 272 * fdt_header_size - return the size of the tree's header
 273 * @fdt: pointer to a flattened device tree
 274 *
 275 * Return: size of DTB header in bytes
 276 */
 277size_t fdt_header_size(const void *fdt);
 278
 279/**
 280 * fdt_header_size_ - internal function to get header size from a version number
 281 * @version: devicetree version number
 282 *
 283 * Return: size of DTB header in bytes
 284 */
 285size_t fdt_header_size_(uint32_t version);
 286
 287/**
 288 * fdt_check_header - sanity check a device tree header
 289 * @fdt: pointer to data which might be a flattened device tree
 290 *
 291 * fdt_check_header() checks that the given buffer contains what
 292 * appears to be a flattened device tree, and that the header contains
 293 * valid information (to the extent that can be determined from the
 294 * header alone).
 295 *
 296 * returns:
 297 *     0, if the buffer appears to contain a valid device tree
 298 *     -FDT_ERR_BADMAGIC,
 299 *     -FDT_ERR_BADVERSION,
 300 *     -FDT_ERR_BADSTATE,
 301 *     -FDT_ERR_TRUNCATED, standard meanings, as above
 302 */
 303int fdt_check_header(const void *fdt);
 304
 305/**
 306 * fdt_move - move a device tree around in memory
 307 * @fdt: pointer to the device tree to move
 308 * @buf: pointer to memory where the device is to be moved
 309 * @bufsize: size of the memory space at buf
 310 *
 311 * fdt_move() relocates, if possible, the device tree blob located at
 312 * fdt to the buffer at buf of size bufsize.  The buffer may overlap
 313 * with the existing device tree blob at fdt.  Therefore,
 314 *     fdt_move(fdt, fdt, fdt_totalsize(fdt))
 315 * should always succeed.
 316 *
 317 * returns:
 318 *     0, on success
 319 *     -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
 320 *     -FDT_ERR_BADMAGIC,
 321 *     -FDT_ERR_BADVERSION,
 322 *     -FDT_ERR_BADSTATE, standard meanings
 323 */
 324int fdt_move(const void *fdt, void *buf, int bufsize);
 325
 326/**********************************************************************/
 327/* Read-only functions                                                */
 328/**********************************************************************/
 329
 330int fdt_check_full(const void *fdt, size_t bufsize);
 331
 332/**
 333 * fdt_get_string - retrieve a string from the strings block of a device tree
 334 * @fdt: pointer to the device tree blob
 335 * @stroffset: offset of the string within the strings block (native endian)
 336 * @lenp: optional pointer to return the string's length
 337 *
 338 * fdt_get_string() retrieves a pointer to a single string from the
 339 * strings block of the device tree blob at fdt, and optionally also
 340 * returns the string's length in *lenp.
 341 *
 342 * returns:
 343 *     a pointer to the string, on success
 344 *     NULL, if stroffset is out of bounds, or doesn't point to a valid string
 345 */
 346const char *fdt_get_string(const void *fdt, int stroffset, int *lenp);
 347
 348/**
 349 * fdt_string - retrieve a string from the strings block of a device tree
 350 * @fdt: pointer to the device tree blob
 351 * @stroffset: offset of the string within the strings block (native endian)
 352 *
 353 * fdt_string() retrieves a pointer to a single string from the
 354 * strings block of the device tree blob at fdt.
 355 *
 356 * returns:
 357 *     a pointer to the string, on success
 358 *     NULL, if stroffset is out of bounds, or doesn't point to a valid string
 359 */
 360const char *fdt_string(const void *fdt, int stroffset);
 361
 362/**
 363 * fdt_find_max_phandle - find and return the highest phandle in a tree
 364 * @fdt: pointer to the device tree blob
 365 * @phandle: return location for the highest phandle value found in the tree
 366 *
 367 * fdt_find_max_phandle() finds the highest phandle value in the given device
 368 * tree. The value returned in @phandle is only valid if the function returns
 369 * success.
 370 *
 371 * returns:
 372 *     0 on success or a negative error code on failure
 373 */
 374int fdt_find_max_phandle(const void *fdt, uint32_t *phandle);
 375
 376/**
 377 * fdt_get_max_phandle - retrieves the highest phandle in a tree
 378 * @fdt: pointer to the device tree blob
 379 *
 380 * fdt_get_max_phandle retrieves the highest phandle in the given
 381 * device tree. This will ignore badly formatted phandles, or phandles
 382 * with a value of 0 or -1.
 383 *
 384 * This function is deprecated in favour of fdt_find_max_phandle().
 385 *
 386 * returns:
 387 *      the highest phandle on success
 388 *      0, if no phandle was found in the device tree
 389 *      -1, if an error occurred
 390 */
 391static inline uint32_t fdt_get_max_phandle(const void *fdt)
 392{
 393        uint32_t phandle;
 394        int err;
 395
 396        err = fdt_find_max_phandle(fdt, &phandle);
 397        if (err < 0)
 398                return (uint32_t)-1;
 399
 400        return phandle;
 401}
 402
 403/**
 404 * fdt_generate_phandle - return a new, unused phandle for a device tree blob
 405 * @fdt: pointer to the device tree blob
 406 * @phandle: return location for the new phandle
 407 *
 408 * Walks the device tree blob and looks for the highest phandle value. On
 409 * success, the new, unused phandle value (one higher than the previously
 410 * highest phandle value in the device tree blob) will be returned in the
 411 * @phandle parameter.
 412 *
 413 * Return: 0 on success or a negative error-code on failure
 414 */
 415int fdt_generate_phandle(const void *fdt, uint32_t *phandle);
 416
 417/**
 418 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
 419 * @fdt: pointer to the device tree blob
 420 *
 421 * Returns the number of entries in the device tree blob's memory
 422 * reservation map.  This does not include the terminating 0,0 entry
 423 * or any other (0,0) entries reserved for expansion.
 424 *
 425 * returns:
 426 *     the number of entries
 427 */
 428int fdt_num_mem_rsv(const void *fdt);
 429
 430/**
 431 * fdt_get_mem_rsv - retrieve one memory reserve map entry
 432 * @fdt: pointer to the device tree blob
 433 * @n: index of reserve map entry
 434 * @address: pointer to 64-bit variable to hold the start address
 435 * @size: pointer to 64-bit variable to hold the size of the entry
 436 *
 437 * On success, @address and @size will contain the address and size of
 438 * the n-th reserve map entry from the device tree blob, in
 439 * native-endian format.
 440 *
 441 * returns:
 442 *     0, on success
 443 *     -FDT_ERR_BADMAGIC,
 444 *     -FDT_ERR_BADVERSION,
 445 *     -FDT_ERR_BADSTATE, standard meanings
 446 */
 447int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
 448
 449/**
 450 * fdt_subnode_offset_namelen - find a subnode based on substring
 451 * @fdt: pointer to the device tree blob
 452 * @parentoffset: structure block offset of a node
 453 * @name: name of the subnode to locate
 454 * @namelen: number of characters of name to consider
 455 *
 456 * Identical to fdt_subnode_offset(), but only examine the first
 457 * namelen characters of name for matching the subnode name.  This is
 458 * useful for finding subnodes based on a portion of a larger string,
 459 * such as a full path.
 460 *
 461 * Return: offset of the subnode or -FDT_ERR_NOTFOUND if name not found.
 462 */
 463#ifndef SWIG /* Not available in Python */
 464int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
 465                               const char *name, int namelen);
 466#endif
 467/**
 468 * fdt_subnode_offset - find a subnode of a given node
 469 * @fdt: pointer to the device tree blob
 470 * @parentoffset: structure block offset of a node
 471 * @name: name of the subnode to locate
 472 *
 473 * fdt_subnode_offset() finds a subnode of the node at structure block
 474 * offset parentoffset with the given name.  name may include a unit
 475 * address, in which case fdt_subnode_offset() will find the subnode
 476 * with that unit address, or the unit address may be omitted, in
 477 * which case fdt_subnode_offset() will find an arbitrary subnode
 478 * whose name excluding unit address matches the given name.
 479 *
 480 * returns:
 481 *      structure block offset of the requested subnode (>=0), on success
 482 *      -FDT_ERR_NOTFOUND, if the requested subnode does not exist
 483 *      -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
 484 *              tag
 485 *      -FDT_ERR_BADMAGIC,
 486 *      -FDT_ERR_BADVERSION,
 487 *      -FDT_ERR_BADSTATE,
 488 *      -FDT_ERR_BADSTRUCTURE,
 489 *      -FDT_ERR_TRUNCATED, standard meanings.
 490 */
 491int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
 492
 493/**
 494 * fdt_path_offset_namelen - find a tree node by its full path
 495 * @fdt: pointer to the device tree blob
 496 * @path: full path of the node to locate
 497 * @namelen: number of characters of path to consider
 498 *
 499 * Identical to fdt_path_offset(), but only consider the first namelen
 500 * characters of path as the path name.
 501 *
 502 * Return: offset of the node or negative libfdt error value otherwise
 503 */
 504#ifndef SWIG /* Not available in Python */
 505int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen);
 506#endif
 507
 508/**
 509 * fdt_path_offset - find a tree node by its full path
 510 * @fdt: pointer to the device tree blob
 511 * @path: full path of the node to locate
 512 *
 513 * fdt_path_offset() finds a node of a given path in the device tree.
 514 * Each path component may omit the unit address portion, but the
 515 * results of this are undefined if any such path component is
 516 * ambiguous (that is if there are multiple nodes at the relevant
 517 * level matching the given component, differentiated only by unit
 518 * address).
 519 *
 520 * returns:
 521 *      structure block offset of the node with the requested path (>=0), on
 522 *              success
 523 *      -FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
 524 *      -FDT_ERR_NOTFOUND, if the requested node does not exist
 525 *      -FDT_ERR_BADMAGIC,
 526 *      -FDT_ERR_BADVERSION,
 527 *      -FDT_ERR_BADSTATE,
 528 *      -FDT_ERR_BADSTRUCTURE,
 529 *      -FDT_ERR_TRUNCATED, standard meanings.
 530 */
 531int fdt_path_offset(const void *fdt, const char *path);
 532
 533/**
 534 * fdt_get_name - retrieve the name of a given node
 535 * @fdt: pointer to the device tree blob
 536 * @nodeoffset: structure block offset of the starting node
 537 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 538 *
 539 * fdt_get_name() retrieves the name (including unit address) of the
 540 * device tree node at structure block offset nodeoffset.  If lenp is
 541 * non-NULL, the length of this name is also returned, in the integer
 542 * pointed to by lenp.
 543 *
 544 * returns:
 545 *      pointer to the node's name, on success
 546 *              If lenp is non-NULL, *lenp contains the length of that name
 547 *                      (>=0)
 548 *      NULL, on error
 549 *              if lenp is non-NULL *lenp contains an error code (<0):
 550 *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
 551 *                      tag
 552 *              -FDT_ERR_BADMAGIC,
 553 *              -FDT_ERR_BADVERSION,
 554 *              -FDT_ERR_BADSTATE, standard meanings
 555 */
 556const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
 557
 558/**
 559 * fdt_first_property_offset - find the offset of a node's first property
 560 * @fdt: pointer to the device tree blob
 561 * @nodeoffset: structure block offset of a node
 562 *
 563 * fdt_first_property_offset() finds the first property of the node at
 564 * the given structure block offset.
 565 *
 566 * returns:
 567 *      structure block offset of the property (>=0), on success
 568 *      -FDT_ERR_NOTFOUND, if the requested node has no properties
 569 *      -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
 570 *      -FDT_ERR_BADMAGIC,
 571 *      -FDT_ERR_BADVERSION,
 572 *      -FDT_ERR_BADSTATE,
 573 *      -FDT_ERR_BADSTRUCTURE,
 574 *      -FDT_ERR_TRUNCATED, standard meanings.
 575 */
 576int fdt_first_property_offset(const void *fdt, int nodeoffset);
 577
 578/**
 579 * fdt_next_property_offset - step through a node's properties
 580 * @fdt: pointer to the device tree blob
 581 * @offset: structure block offset of a property
 582 *
 583 * fdt_next_property_offset() finds the property immediately after the
 584 * one at the given structure block offset.  This will be a property
 585 * of the same node as the given property.
 586 *
 587 * returns:
 588 *      structure block offset of the next property (>=0), on success
 589 *      -FDT_ERR_NOTFOUND, if the given property is the last in its node
 590 *      -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag
 591 *      -FDT_ERR_BADMAGIC,
 592 *      -FDT_ERR_BADVERSION,
 593 *      -FDT_ERR_BADSTATE,
 594 *      -FDT_ERR_BADSTRUCTURE,
 595 *      -FDT_ERR_TRUNCATED, standard meanings.
 596 */
 597int fdt_next_property_offset(const void *fdt, int offset);
 598
 599/**
 600 * fdt_for_each_property_offset - iterate over all properties of a node
 601 *
 602 * @property:   property offset (int, lvalue)
 603 * @fdt:        FDT blob (const void *)
 604 * @node:       node offset (int)
 605 *
 606 * This is actually a wrapper around a for loop and would be used like so:
 607 *
 608 *      fdt_for_each_property_offset(property, fdt, node) {
 609 *              Use property
 610 *              ...
 611 *      }
 612 *
 613 *      if ((property < 0) && (property != -FDT_ERR_NOTFOUND)) {
 614 *              Error handling
 615 *      }
 616 *
 617 * Note that this is implemented as a macro and property is used as
 618 * iterator in the loop. The node variable can be constant or even a
 619 * literal.
 620 */
 621#define fdt_for_each_property_offset(property, fdt, node)       \
 622        for (property = fdt_first_property_offset(fdt, node);   \
 623             property >= 0;                                     \
 624             property = fdt_next_property_offset(fdt, property))
 625
 626/**
 627 * fdt_get_property_by_offset - retrieve the property at a given offset
 628 * @fdt: pointer to the device tree blob
 629 * @offset: offset of the property to retrieve
 630 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 631 *
 632 * fdt_get_property_by_offset() retrieves a pointer to the
 633 * fdt_property structure within the device tree blob at the given
 634 * offset.  If lenp is non-NULL, the length of the property value is
 635 * also returned, in the integer pointed to by lenp.
 636 *
 637 * Note that this code only works on device tree versions >= 16. fdt_getprop()
 638 * works on all versions.
 639 *
 640 * returns:
 641 *      pointer to the structure representing the property
 642 *              if lenp is non-NULL, *lenp contains the length of the property
 643 *              value (>=0)
 644 *      NULL, on error
 645 *              if lenp is non-NULL, *lenp contains an error code (<0):
 646 *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
 647 *              -FDT_ERR_BADMAGIC,
 648 *              -FDT_ERR_BADVERSION,
 649 *              -FDT_ERR_BADSTATE,
 650 *              -FDT_ERR_BADSTRUCTURE,
 651 *              -FDT_ERR_TRUNCATED, standard meanings
 652 */
 653const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
 654                                                      int offset,
 655                                                      int *lenp);
 656
 657/**
 658 * fdt_get_property_namelen - find a property based on substring
 659 * @fdt: pointer to the device tree blob
 660 * @nodeoffset: offset of the node whose property to find
 661 * @name: name of the property to find
 662 * @namelen: number of characters of name to consider
 663 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 664 *
 665 * Identical to fdt_get_property(), but only examine the first namelen
 666 * characters of name for matching the property name.
 667 *
 668 * Return: pointer to the structure representing the property, or NULL
 669 *         if not found
 670 */
 671#ifndef SWIG /* Not available in Python */
 672const struct fdt_property *fdt_get_property_namelen(const void *fdt,
 673                                                    int nodeoffset,
 674                                                    const char *name,
 675                                                    int namelen, int *lenp);
 676#endif
 677
 678/**
 679 * fdt_get_property - find a given property in a given node
 680 * @fdt: pointer to the device tree blob
 681 * @nodeoffset: offset of the node whose property to find
 682 * @name: name of the property to find
 683 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 684 *
 685 * fdt_get_property() retrieves a pointer to the fdt_property
 686 * structure within the device tree blob corresponding to the property
 687 * named 'name' of the node at offset nodeoffset.  If lenp is
 688 * non-NULL, the length of the property value is also returned, in the
 689 * integer pointed to by lenp.
 690 *
 691 * returns:
 692 *      pointer to the structure representing the property
 693 *              if lenp is non-NULL, *lenp contains the length of the property
 694 *              value (>=0)
 695 *      NULL, on error
 696 *              if lenp is non-NULL, *lenp contains an error code (<0):
 697 *              -FDT_ERR_NOTFOUND, node does not have named property
 698 *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
 699 *                      tag
 700 *              -FDT_ERR_BADMAGIC,
 701 *              -FDT_ERR_BADVERSION,
 702 *              -FDT_ERR_BADSTATE,
 703 *              -FDT_ERR_BADSTRUCTURE,
 704 *              -FDT_ERR_TRUNCATED, standard meanings
 705 */
 706const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
 707                                            const char *name, int *lenp);
 708static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
 709                                                      const char *name,
 710                                                      int *lenp)
 711{
 712        return (struct fdt_property *)(uintptr_t)
 713                fdt_get_property(fdt, nodeoffset, name, lenp);
 714}
 715
 716/**
 717 * fdt_getprop_by_offset - retrieve the value of a property at a given offset
 718 * @fdt: pointer to the device tree blob
 719 * @offset: offset of the property to read
 720 * @namep: pointer to a string variable (will be overwritten) or NULL
 721 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 722 *
 723 * fdt_getprop_by_offset() retrieves a pointer to the value of the
 724 * property at structure block offset 'offset' (this will be a pointer
 725 * to within the device blob itself, not a copy of the value).  If
 726 * lenp is non-NULL, the length of the property value is also
 727 * returned, in the integer pointed to by lenp.  If namep is non-NULL,
 728 * the property's namne will also be returned in the char * pointed to
 729 * by namep (this will be a pointer to within the device tree's string
 730 * block, not a new copy of the name).
 731 *
 732 * returns:
 733 *      pointer to the property's value
 734 *              if lenp is non-NULL, *lenp contains the length of the property
 735 *              value (>=0)
 736 *              if namep is non-NULL *namep contiains a pointer to the property
 737 *              name.
 738 *      NULL, on error
 739 *              if lenp is non-NULL, *lenp contains an error code (<0):
 740 *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
 741 *              -FDT_ERR_BADMAGIC,
 742 *              -FDT_ERR_BADVERSION,
 743 *              -FDT_ERR_BADSTATE,
 744 *              -FDT_ERR_BADSTRUCTURE,
 745 *              -FDT_ERR_TRUNCATED, standard meanings
 746 */
 747#ifndef SWIG /* This function is not useful in Python */
 748const void *fdt_getprop_by_offset(const void *fdt, int offset,
 749                                  const char **namep, int *lenp);
 750#endif
 751
 752/**
 753 * fdt_getprop_namelen - get property value based on substring
 754 * @fdt: pointer to the device tree blob
 755 * @nodeoffset: offset of the node whose property to find
 756 * @name: name of the property to find
 757 * @namelen: number of characters of name to consider
 758 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 759 *
 760 * Identical to fdt_getprop(), but only examine the first namelen
 761 * characters of name for matching the property name.
 762 *
 763 * Return: pointer to the property's value or NULL on error
 764 */
 765#ifndef SWIG /* Not available in Python */
 766const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
 767                                const char *name, int namelen, int *lenp);
 768static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset,
 769                                          const char *name, int namelen,
 770                                          int *lenp)
 771{
 772        return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name,
 773                                                      namelen, lenp);
 774}
 775#endif
 776
 777/**
 778 * fdt_getprop - retrieve the value of a given property
 779 * @fdt: pointer to the device tree blob
 780 * @nodeoffset: offset of the node whose property to find
 781 * @name: name of the property to find
 782 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 783 *
 784 * fdt_getprop() retrieves a pointer to the value of the property
 785 * named @name of the node at offset @nodeoffset (this will be a
 786 * pointer to within the device blob itself, not a copy of the value).
 787 * If @lenp is non-NULL, the length of the property value is also
 788 * returned, in the integer pointed to by @lenp.
 789 *
 790 * returns:
 791 *      pointer to the property's value
 792 *              if lenp is non-NULL, *lenp contains the length of the property
 793 *              value (>=0)
 794 *      NULL, on error
 795 *              if lenp is non-NULL, *lenp contains an error code (<0):
 796 *              -FDT_ERR_NOTFOUND, node does not have named property
 797 *              -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
 798 *                      tag
 799 *              -FDT_ERR_BADMAGIC,
 800 *              -FDT_ERR_BADVERSION,
 801 *              -FDT_ERR_BADSTATE,
 802 *              -FDT_ERR_BADSTRUCTURE,
 803 *              -FDT_ERR_TRUNCATED, standard meanings
 804 */
 805const void *fdt_getprop(const void *fdt, int nodeoffset,
 806                        const char *name, int *lenp);
 807static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
 808                                  const char *name, int *lenp)
 809{
 810        return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
 811}
 812
 813/**
 814 * fdt_get_phandle - retrieve the phandle of a given node
 815 * @fdt: pointer to the device tree blob
 816 * @nodeoffset: structure block offset of the node
 817 *
 818 * fdt_get_phandle() retrieves the phandle of the device tree node at
 819 * structure block offset nodeoffset.
 820 *
 821 * returns:
 822 *      the phandle of the node at nodeoffset, on success (!= 0, != -1)
 823 *      0, if the node has no phandle, or another error occurs
 824 */
 825uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
 826
 827/**
 828 * fdt_get_alias_namelen - get alias based on substring
 829 * @fdt: pointer to the device tree blob
 830 * @name: name of the alias th look up
 831 * @namelen: number of characters of name to consider
 832 *
 833 * Identical to fdt_get_alias(), but only examine the first @namelen
 834 * characters of @name for matching the alias name.
 835 *
 836 * Return: a pointer to the expansion of the alias named @name, if it exists,
 837 *         NULL otherwise
 838 */
 839#ifndef SWIG /* Not available in Python */
 840const char *fdt_get_alias_namelen(const void *fdt,
 841                                  const char *name, int namelen);
 842#endif
 843
 844/**
 845 * fdt_get_alias - retrieve the path referenced by a given alias
 846 * @fdt: pointer to the device tree blob
 847 * @name: name of the alias th look up
 848 *
 849 * fdt_get_alias() retrieves the value of a given alias.  That is, the
 850 * value of the property named @name in the node /aliases.
 851 *
 852 * returns:
 853 *      a pointer to the expansion of the alias named 'name', if it exists
 854 *      NULL, if the given alias or the /aliases node does not exist
 855 */
 856const char *fdt_get_alias(const void *fdt, const char *name);
 857
 858/**
 859 * fdt_get_path - determine the full path of a node
 860 * @fdt: pointer to the device tree blob
 861 * @nodeoffset: offset of the node whose path to find
 862 * @buf: character buffer to contain the returned path (will be overwritten)
 863 * @buflen: size of the character buffer at buf
 864 *
 865 * fdt_get_path() computes the full path of the node at offset
 866 * nodeoffset, and records that path in the buffer at buf.
 867 *
 868 * NOTE: This function is expensive, as it must scan the device tree
 869 * structure from the start to nodeoffset.
 870 *
 871 * returns:
 872 *      0, on success
 873 *              buf contains the absolute path of the node at
 874 *              nodeoffset, as a NUL-terminated string.
 875 *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 876 *      -FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
 877 *              characters and will not fit in the given buffer.
 878 *      -FDT_ERR_BADMAGIC,
 879 *      -FDT_ERR_BADVERSION,
 880 *      -FDT_ERR_BADSTATE,
 881 *      -FDT_ERR_BADSTRUCTURE, standard meanings
 882 */
 883int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
 884
 885/**
 886 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
 887 * @fdt: pointer to the device tree blob
 888 * @nodeoffset: offset of the node whose parent to find
 889 * @supernodedepth: depth of the ancestor to find
 890 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
 891 *
 892 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
 893 * at a specific depth from the root (where the root itself has depth
 894 * 0, its immediate subnodes depth 1 and so forth).  So
 895 *      fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
 896 * will always return 0, the offset of the root node.  If the node at
 897 * nodeoffset has depth D, then:
 898 *      fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
 899 * will return nodeoffset itself.
 900 *
 901 * NOTE: This function is expensive, as it must scan the device tree
 902 * structure from the start to nodeoffset.
 903 *
 904 * returns:
 905 *      structure block offset of the node at node offset's ancestor
 906 *              of depth supernodedepth (>=0), on success
 907 *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 908 *      -FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of
 909 *              nodeoffset
 910 *      -FDT_ERR_BADMAGIC,
 911 *      -FDT_ERR_BADVERSION,
 912 *      -FDT_ERR_BADSTATE,
 913 *      -FDT_ERR_BADSTRUCTURE, standard meanings
 914 */
 915int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
 916                                 int supernodedepth, int *nodedepth);
 917
 918/**
 919 * fdt_node_depth - find the depth of a given node
 920 * @fdt: pointer to the device tree blob
 921 * @nodeoffset: offset of the node whose parent to find
 922 *
 923 * fdt_node_depth() finds the depth of a given node.  The root node
 924 * has depth 0, its immediate subnodes depth 1 and so forth.
 925 *
 926 * NOTE: This function is expensive, as it must scan the device tree
 927 * structure from the start to nodeoffset.
 928 *
 929 * returns:
 930 *      depth of the node at nodeoffset (>=0), on success
 931 *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 932 *      -FDT_ERR_BADMAGIC,
 933 *      -FDT_ERR_BADVERSION,
 934 *      -FDT_ERR_BADSTATE,
 935 *      -FDT_ERR_BADSTRUCTURE, standard meanings
 936 */
 937int fdt_node_depth(const void *fdt, int nodeoffset);
 938
 939/**
 940 * fdt_parent_offset - find the parent of a given node
 941 * @fdt: pointer to the device tree blob
 942 * @nodeoffset: offset of the node whose parent to find
 943 *
 944 * fdt_parent_offset() locates the parent node of a given node (that
 945 * is, it finds the offset of the node which contains the node at
 946 * nodeoffset as a subnode).
 947 *
 948 * NOTE: This function is expensive, as it must scan the device tree
 949 * structure from the start to nodeoffset, *twice*.
 950 *
 951 * returns:
 952 *      structure block offset of the parent of the node at nodeoffset
 953 *              (>=0), on success
 954 *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 955 *      -FDT_ERR_BADMAGIC,
 956 *      -FDT_ERR_BADVERSION,
 957 *      -FDT_ERR_BADSTATE,
 958 *      -FDT_ERR_BADSTRUCTURE, standard meanings
 959 */
 960int fdt_parent_offset(const void *fdt, int nodeoffset);
 961
 962/**
 963 * fdt_node_offset_by_prop_value - find nodes with a given property value
 964 * @fdt: pointer to the device tree blob
 965 * @startoffset: only find nodes after this offset
 966 * @propname: property name to check
 967 * @propval: property value to search for
 968 * @proplen: length of the value in propval
 969 *
 970 * fdt_node_offset_by_prop_value() returns the offset of the first
 971 * node after startoffset, which has a property named propname whose
 972 * value is of length proplen and has value equal to propval; or if
 973 * startoffset is -1, the very first such node in the tree.
 974 *
 975 * To iterate through all nodes matching the criterion, the following
 976 * idiom can be used:
 977 *      offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
 978 *                                             propval, proplen);
 979 *      while (offset != -FDT_ERR_NOTFOUND) {
 980 *              // other code here
 981 *              offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
 982 *                                                     propval, proplen);
 983 *      }
 984 *
 985 * Note the -1 in the first call to the function, if 0 is used here
 986 * instead, the function will never locate the root node, even if it
 987 * matches the criterion.
 988 *
 989 * returns:
 990 *      structure block offset of the located node (>= 0, >startoffset),
 991 *               on success
 992 *      -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
 993 *              tree after startoffset
 994 *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 995 *      -FDT_ERR_BADMAGIC,
 996 *      -FDT_ERR_BADVERSION,
 997 *      -FDT_ERR_BADSTATE,
 998 *      -FDT_ERR_BADSTRUCTURE, standard meanings
 999 */
1000int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
1001                                  const char *propname,
1002                                  const void *propval, int proplen);
1003
1004/**
1005 * fdt_node_offset_by_phandle - find the node with a given phandle
1006 * @fdt: pointer to the device tree blob
1007 * @phandle: phandle value
1008 *
1009 * fdt_node_offset_by_phandle() returns the offset of the node
1010 * which has the given phandle value.  If there is more than one node
1011 * in the tree with the given phandle (an invalid tree), results are
1012 * undefined.
1013 *
1014 * returns:
1015 *      structure block offset of the located node (>= 0), on success
1016 *      -FDT_ERR_NOTFOUND, no node with that phandle exists
1017 *      -FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
1018 *      -FDT_ERR_BADMAGIC,
1019 *      -FDT_ERR_BADVERSION,
1020 *      -FDT_ERR_BADSTATE,
1021 *      -FDT_ERR_BADSTRUCTURE, standard meanings
1022 */
1023int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
1024
1025/**
1026 * fdt_node_check_compatible - check a node's compatible property
1027 * @fdt: pointer to the device tree blob
1028 * @nodeoffset: offset of a tree node
1029 * @compatible: string to match against
1030 *
1031 * fdt_node_check_compatible() returns 0 if the given node contains a
1032 * @compatible property with the given string as one of its elements,
1033 * it returns non-zero otherwise, or on error.
1034 *
1035 * returns:
1036 *      0, if the node has a 'compatible' property listing the given string
1037 *      1, if the node has a 'compatible' property, but it does not list
1038 *              the given string
1039 *      -FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
1040 *      -FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
1041 *      -FDT_ERR_BADMAGIC,
1042 *      -FDT_ERR_BADVERSION,
1043 *      -FDT_ERR_BADSTATE,
1044 *      -FDT_ERR_BADSTRUCTURE, standard meanings
1045 */
1046int fdt_node_check_compatible(const void *fdt, int nodeoffset,
1047                              const char *compatible);
1048
1049/**
1050 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
1051 * @fdt: pointer to the device tree blob
1052 * @startoffset: only find nodes after this offset
1053 * @compatible: 'compatible' string to match against
1054 *
1055 * fdt_node_offset_by_compatible() returns the offset of the first
1056 * node after startoffset, which has a 'compatible' property which
1057 * lists the given compatible string; or if startoffset is -1, the
1058 * very first such node in the tree.
1059 *
1060 * To iterate through all nodes matching the criterion, the following
1061 * idiom can be used:
1062 *      offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
1063 *      while (offset != -FDT_ERR_NOTFOUND) {
1064 *              // other code here
1065 *              offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
1066 *      }
1067 *
1068 * Note the -1 in the first call to the function, if 0 is used here
1069 * instead, the function will never locate the root node, even if it
1070 * matches the criterion.
1071 *
1072 * returns:
1073 *      structure block offset of the located node (>= 0, >startoffset),
1074 *               on success
1075 *      -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
1076 *              tree after startoffset
1077 *      -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1078 *      -FDT_ERR_BADMAGIC,
1079 *      -FDT_ERR_BADVERSION,
1080 *      -FDT_ERR_BADSTATE,
1081 *      -FDT_ERR_BADSTRUCTURE, standard meanings
1082 */
1083int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
1084                                  const char *compatible);
1085
1086/**
1087 * fdt_stringlist_contains - check a string list property for a string
1088 * @strlist: Property containing a list of strings to check
1089 * @listlen: Length of property
1090 * @str: String to search for
1091 *
1092 * This is a utility function provided for convenience. The list contains
1093 * one or more strings, each terminated by \0, as is found in a device tree
1094 * "compatible" property.
1095 *
1096 * Return: 1 if the string is found in the list, 0 not found, or invalid list
1097 */
1098int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
1099
1100/**
1101 * fdt_stringlist_count - count the number of strings in a string list
1102 * @fdt: pointer to the device tree blob
1103 * @nodeoffset: offset of a tree node
1104 * @property: name of the property containing the string list
1105 *
1106 * Return:
1107 *   the number of strings in the given property
1108 *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1109 *   -FDT_ERR_NOTFOUND if the property does not exist
1110 */
1111int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property);
1112
1113/**
1114 * fdt_stringlist_search - find a string in a string list and return its index
1115 * @fdt: pointer to the device tree blob
1116 * @nodeoffset: offset of a tree node
1117 * @property: name of the property containing the string list
1118 * @string: string to look up in the string list
1119 *
1120 * Note that it is possible for this function to succeed on property values
1121 * that are not NUL-terminated. That's because the function will stop after
1122 * finding the first occurrence of @string. This can for example happen with
1123 * small-valued cell properties, such as #address-cells, when searching for
1124 * the empty string.
1125 *
1126 * return:
1127 *   the index of the string in the list of strings
1128 *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1129 *   -FDT_ERR_NOTFOUND if the property does not exist or does not contain
1130 *                     the given string
1131 */
1132int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
1133                          const char *string);
1134
1135/**
1136 * fdt_stringlist_get() - obtain the string at a given index in a string list
1137 * @fdt: pointer to the device tree blob
1138 * @nodeoffset: offset of a tree node
1139 * @property: name of the property containing the string list
1140 * @index: index of the string to return
1141 * @lenp: return location for the string length or an error code on failure
1142 *
1143 * Note that this will successfully extract strings from properties with
1144 * non-NUL-terminated values. For example on small-valued cell properties
1145 * this function will return the empty string.
1146 *
1147 * If non-NULL, the length of the string (on success) or a negative error-code
1148 * (on failure) will be stored in the integer pointer to by lenp.
1149 *
1150 * Return:
1151 *   A pointer to the string at the given index in the string list or NULL on
1152 *   failure. On success the length of the string will be stored in the memory
1153 *   location pointed to by the lenp parameter, if non-NULL. On failure one of
1154 *   the following negative error codes will be returned in the lenp parameter
1155 *   (if non-NULL):
1156 *     -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1157 *     -FDT_ERR_NOTFOUND if the property does not exist
1158 */
1159const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
1160                               const char *property, int index,
1161                               int *lenp);
1162
1163/**********************************************************************/
1164/* Read-only functions (addressing related)                           */
1165/**********************************************************************/
1166
1167/**
1168 * FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells
1169 *
1170 * This is the maximum value for #address-cells, #size-cells and
1171 * similar properties that will be processed by libfdt.  IEE1275
1172 * requires that OF implementations handle values up to 4.
1173 * Implementations may support larger values, but in practice higher
1174 * values aren't used.
1175 */
1176#define FDT_MAX_NCELLS          4
1177
1178/**
1179 * fdt_address_cells - retrieve address size for a bus represented in the tree
1180 * @fdt: pointer to the device tree blob
1181 * @nodeoffset: offset of the node to find the address size for
1182 *
1183 * When the node has a valid #address-cells property, returns its value.
1184 *
1185 * returns:
1186 *      0 <= n < FDT_MAX_NCELLS, on success
1187 *      2, if the node has no #address-cells property
1188 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1189 *              #address-cells property
1190 *      -FDT_ERR_BADMAGIC,
1191 *      -FDT_ERR_BADVERSION,
1192 *      -FDT_ERR_BADSTATE,
1193 *      -FDT_ERR_BADSTRUCTURE,
1194 *      -FDT_ERR_TRUNCATED, standard meanings
1195 */
1196int fdt_address_cells(const void *fdt, int nodeoffset);
1197
1198/**
1199 * fdt_size_cells - retrieve address range size for a bus represented in the
1200 *                  tree
1201 * @fdt: pointer to the device tree blob
1202 * @nodeoffset: offset of the node to find the address range size for
1203 *
1204 * When the node has a valid #size-cells property, returns its value.
1205 *
1206 * returns:
1207 *      0 <= n < FDT_MAX_NCELLS, on success
1208 *      1, if the node has no #size-cells property
1209 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1210 *              #size-cells property
1211 *      -FDT_ERR_BADMAGIC,
1212 *      -FDT_ERR_BADVERSION,
1213 *      -FDT_ERR_BADSTATE,
1214 *      -FDT_ERR_BADSTRUCTURE,
1215 *      -FDT_ERR_TRUNCATED, standard meanings
1216 */
1217int fdt_size_cells(const void *fdt, int nodeoffset);
1218
1219
1220/**********************************************************************/
1221/* Write-in-place functions                                           */
1222/**********************************************************************/
1223
1224/**
1225 * fdt_setprop_inplace_namelen_partial - change a property's value,
1226 *                                       but not its size
1227 * @fdt: pointer to the device tree blob
1228 * @nodeoffset: offset of the node whose property to change
1229 * @name: name of the property to change
1230 * @namelen: number of characters of name to consider
1231 * @idx: index of the property to change in the array
1232 * @val: pointer to data to replace the property value with
1233 * @len: length of the property value
1234 *
1235 * Identical to fdt_setprop_inplace(), but modifies the given property
1236 * starting from the given index, and using only the first characters
1237 * of the name. It is useful when you want to manipulate only one value of
1238 * an array and you have a string that doesn't end with \0.
1239 *
1240 * Return: 0 on success, negative libfdt error value otherwise
1241 */
1242#ifndef SWIG /* Not available in Python */
1243int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
1244                                        const char *name, int namelen,
1245                                        uint32_t idx, const void *val,
1246                                        int len);
1247#endif
1248
1249/**
1250 * fdt_setprop_inplace - change a property's value, but not its size
1251 * @fdt: pointer to the device tree blob
1252 * @nodeoffset: offset of the node whose property to change
1253 * @name: name of the property to change
1254 * @val: pointer to data to replace the property value with
1255 * @len: length of the property value
1256 *
1257 * fdt_setprop_inplace() replaces the value of a given property with
1258 * the data in val, of length len.  This function cannot change the
1259 * size of a property, and so will only work if len is equal to the
1260 * current length of the property.
1261 *
1262 * This function will alter only the bytes in the blob which contain
1263 * the given property value, and will not alter or move any other part
1264 * of the tree.
1265 *
1266 * returns:
1267 *      0, on success
1268 *      -FDT_ERR_NOSPACE, if len is not equal to the property's current length
1269 *      -FDT_ERR_NOTFOUND, node does not have the named property
1270 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1271 *      -FDT_ERR_BADMAGIC,
1272 *      -FDT_ERR_BADVERSION,
1273 *      -FDT_ERR_BADSTATE,
1274 *      -FDT_ERR_BADSTRUCTURE,
1275 *      -FDT_ERR_TRUNCATED, standard meanings
1276 */
1277#ifndef SWIG /* Not available in Python */
1278int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
1279                        const void *val, int len);
1280#endif
1281
1282/**
1283 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
1284 * @fdt: pointer to the device tree blob
1285 * @nodeoffset: offset of the node whose property to change
1286 * @name: name of the property to change
1287 * @val: 32-bit integer value to replace the property with
1288 *
1289 * fdt_setprop_inplace_u32() replaces the value of a given property
1290 * with the 32-bit integer value in val, converting val to big-endian
1291 * if necessary.  This function cannot change the size of a property,
1292 * and so will only work if the property already exists and has length
1293 * 4.
1294 *
1295 * This function will alter only the bytes in the blob which contain
1296 * the given property value, and will not alter or move any other part
1297 * of the tree.
1298 *
1299 * returns:
1300 *      0, on success
1301 *      -FDT_ERR_NOSPACE, if the property's length is not equal to 4
1302 *      -FDT_ERR_NOTFOUND, node does not have the named property
1303 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1304 *      -FDT_ERR_BADMAGIC,
1305 *      -FDT_ERR_BADVERSION,
1306 *      -FDT_ERR_BADSTATE,
1307 *      -FDT_ERR_BADSTRUCTURE,
1308 *      -FDT_ERR_TRUNCATED, standard meanings
1309 */
1310static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
1311                                          const char *name, uint32_t val)
1312{
1313        fdt32_t tmp = cpu_to_fdt32(val);
1314        return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1315}
1316
1317/**
1318 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
1319 * @fdt: pointer to the device tree blob
1320 * @nodeoffset: offset of the node whose property to change
1321 * @name: name of the property to change
1322 * @val: 64-bit integer value to replace the property with
1323 *
1324 * fdt_setprop_inplace_u64() replaces the value of a given property
1325 * with the 64-bit integer value in val, converting val to big-endian
1326 * if necessary.  This function cannot change the size of a property,
1327 * and so will only work if the property already exists and has length
1328 * 8.
1329 *
1330 * This function will alter only the bytes in the blob which contain
1331 * the given property value, and will not alter or move any other part
1332 * of the tree.
1333 *
1334 * returns:
1335 *      0, on success
1336 *      -FDT_ERR_NOSPACE, if the property's length is not equal to 8
1337 *      -FDT_ERR_NOTFOUND, node does not have the named property
1338 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1339 *      -FDT_ERR_BADMAGIC,
1340 *      -FDT_ERR_BADVERSION,
1341 *      -FDT_ERR_BADSTATE,
1342 *      -FDT_ERR_BADSTRUCTURE,
1343 *      -FDT_ERR_TRUNCATED, standard meanings
1344 */
1345static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
1346                                          const char *name, uint64_t val)
1347{
1348        fdt64_t tmp = cpu_to_fdt64(val);
1349        return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1350}
1351
1352/**
1353 * fdt_setprop_inplace_cell - change the value of a single-cell property
1354 * @fdt: pointer to the device tree blob
1355 * @nodeoffset: offset of the node containing the property
1356 * @name: name of the property to change the value of
1357 * @val: new value of the 32-bit cell
1358 *
1359 * This is an alternative name for fdt_setprop_inplace_u32()
1360 * Return: 0 on success, negative libfdt error number otherwise.
1361 */
1362static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
1363                                           const char *name, uint32_t val)
1364{
1365        return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
1366}
1367
1368/**
1369 * fdt_nop_property - replace a property with nop tags
1370 * @fdt: pointer to the device tree blob
1371 * @nodeoffset: offset of the node whose property to nop
1372 * @name: name of the property to nop
1373 *
1374 * fdt_nop_property() will replace a given property's representation
1375 * in the blob with FDT_NOP tags, effectively removing it from the
1376 * tree.
1377 *
1378 * This function will alter only the bytes in the blob which contain
1379 * the property, and will not alter or move any other part of the
1380 * tree.
1381 *
1382 * returns:
1383 *      0, on success
1384 *      -FDT_ERR_NOTFOUND, node does not have the named property
1385 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1386 *      -FDT_ERR_BADMAGIC,
1387 *      -FDT_ERR_BADVERSION,
1388 *      -FDT_ERR_BADSTATE,
1389 *      -FDT_ERR_BADSTRUCTURE,
1390 *      -FDT_ERR_TRUNCATED, standard meanings
1391 */
1392int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
1393
1394/**
1395 * fdt_nop_node - replace a node (subtree) with nop tags
1396 * @fdt: pointer to the device tree blob
1397 * @nodeoffset: offset of the node to nop
1398 *
1399 * fdt_nop_node() will replace a given node's representation in the
1400 * blob, including all its subnodes, if any, with FDT_NOP tags,
1401 * effectively removing it from the tree.
1402 *
1403 * This function will alter only the bytes in the blob which contain
1404 * the node and its properties and subnodes, and will not alter or
1405 * move any other part of the tree.
1406 *
1407 * returns:
1408 *      0, on success
1409 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1410 *      -FDT_ERR_BADMAGIC,
1411 *      -FDT_ERR_BADVERSION,
1412 *      -FDT_ERR_BADSTATE,
1413 *      -FDT_ERR_BADSTRUCTURE,
1414 *      -FDT_ERR_TRUNCATED, standard meanings
1415 */
1416int fdt_nop_node(void *fdt, int nodeoffset);
1417
1418/**********************************************************************/
1419/* Sequential write functions                                         */
1420/**********************************************************************/
1421
1422/* fdt_create_with_flags flags */
1423#define FDT_CREATE_FLAG_NO_NAME_DEDUP 0x1
1424        /* FDT_CREATE_FLAG_NO_NAME_DEDUP: Do not try to de-duplicate property
1425         * names in the fdt. This can result in faster creation times, but
1426         * a larger fdt. */
1427
1428#define FDT_CREATE_FLAGS_ALL    (FDT_CREATE_FLAG_NO_NAME_DEDUP)
1429
1430/**
1431 * fdt_create_with_flags - begin creation of a new fdt
1432 * @buf: pointer to memory allocated where fdt will be created
1433 * @bufsize: size of the memory space at fdt
1434 * @flags: a valid combination of FDT_CREATE_FLAG_ flags, or 0.
1435 *
1436 * fdt_create_with_flags() begins the process of creating a new fdt with
1437 * the sequential write interface.
1438 *
1439 * fdt creation process must end with fdt_finished() to produce a valid fdt.
1440 *
1441 * returns:
1442 *      0, on success
1443 *      -FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1444 *      -FDT_ERR_BADFLAGS, flags is not valid
1445 */
1446int fdt_create_with_flags(void *buf, int bufsize, uint32_t flags);
1447
1448/**
1449 * fdt_create - begin creation of a new fdt
1450 * @buf: pointer to memory allocated where fdt will be created
1451 * @bufsize: size of the memory space at fdt
1452 *
1453 * fdt_create() is equivalent to fdt_create_with_flags() with flags=0.
1454 *
1455 * returns:
1456 *      0, on success
1457 *      -FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1458 */
1459int fdt_create(void *buf, int bufsize);
1460
1461int fdt_resize(void *fdt, void *buf, int bufsize);
1462int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
1463int fdt_finish_reservemap(void *fdt);
1464int fdt_begin_node(void *fdt, const char *name);
1465int fdt_property(void *fdt, const char *name, const void *val, int len);
1466static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
1467{
1468        fdt32_t tmp = cpu_to_fdt32(val);
1469        return fdt_property(fdt, name, &tmp, sizeof(tmp));
1470}
1471static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
1472{
1473        fdt64_t tmp = cpu_to_fdt64(val);
1474        return fdt_property(fdt, name, &tmp, sizeof(tmp));
1475}
1476
1477#ifndef SWIG /* Not available in Python */
1478static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
1479{
1480        return fdt_property_u32(fdt, name, val);
1481}
1482#endif
1483
1484/**
1485 * fdt_property_placeholder - add a new property and return a ptr to its value
1486 *
1487 * @fdt: pointer to the device tree blob
1488 * @name: name of property to add
1489 * @len: length of property value in bytes
1490 * @valp: returns a pointer to where where the value should be placed
1491 *
1492 * returns:
1493 *      0, on success
1494 *      -FDT_ERR_BADMAGIC,
1495 *      -FDT_ERR_NOSPACE, standard meanings
1496 */
1497int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp);
1498
1499#define fdt_property_string(fdt, name, str) \
1500        fdt_property(fdt, name, str, strlen(str)+1)
1501int fdt_end_node(void *fdt);
1502int fdt_finish(void *fdt);
1503
1504/**********************************************************************/
1505/* Read-write functions                                               */
1506/**********************************************************************/
1507
1508int fdt_create_empty_tree(void *buf, int bufsize);
1509int fdt_open_into(const void *fdt, void *buf, int bufsize);
1510int fdt_pack(void *fdt);
1511
1512/**
1513 * fdt_add_mem_rsv - add one memory reserve map entry
1514 * @fdt: pointer to the device tree blob
1515 * @address: 64-bit start address of the reserve map entry
1516 * @size: 64-bit size of the reserved region
1517 *
1518 * Adds a reserve map entry to the given blob reserving a region at
1519 * address address of length size.
1520 *
1521 * This function will insert data into the reserve map and will
1522 * therefore change the indexes of some entries in the table.
1523 *
1524 * returns:
1525 *      0, on success
1526 *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1527 *              contain the new reservation entry
1528 *      -FDT_ERR_BADMAGIC,
1529 *      -FDT_ERR_BADVERSION,
1530 *      -FDT_ERR_BADSTATE,
1531 *      -FDT_ERR_BADSTRUCTURE,
1532 *      -FDT_ERR_BADLAYOUT,
1533 *      -FDT_ERR_TRUNCATED, standard meanings
1534 */
1535int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
1536
1537/**
1538 * fdt_del_mem_rsv - remove a memory reserve map entry
1539 * @fdt: pointer to the device tree blob
1540 * @n: entry to remove
1541 *
1542 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
1543 * the blob.
1544 *
1545 * This function will delete data from the reservation table and will
1546 * therefore change the indexes of some entries in the table.
1547 *
1548 * returns:
1549 *      0, on success
1550 *      -FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
1551 *              are less than n+1 reserve map entries)
1552 *      -FDT_ERR_BADMAGIC,
1553 *      -FDT_ERR_BADVERSION,
1554 *      -FDT_ERR_BADSTATE,
1555 *      -FDT_ERR_BADSTRUCTURE,
1556 *      -FDT_ERR_BADLAYOUT,
1557 *      -FDT_ERR_TRUNCATED, standard meanings
1558 */
1559int fdt_del_mem_rsv(void *fdt, int n);
1560
1561/**
1562 * fdt_set_name - change the name of a given node
1563 * @fdt: pointer to the device tree blob
1564 * @nodeoffset: structure block offset of a node
1565 * @name: name to give the node
1566 *
1567 * fdt_set_name() replaces the name (including unit address, if any)
1568 * of the given node with the given string.  NOTE: this function can't
1569 * efficiently check if the new name is unique amongst the given
1570 * node's siblings; results are undefined if this function is invoked
1571 * with a name equal to one of the given node's siblings.
1572 *
1573 * This function may insert or delete data from the blob, and will
1574 * therefore change the offsets of some existing nodes.
1575 *
1576 * returns:
1577 *      0, on success
1578 *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob
1579 *              to contain the new name
1580 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1581 *      -FDT_ERR_BADMAGIC,
1582 *      -FDT_ERR_BADVERSION,
1583 *      -FDT_ERR_BADSTATE, standard meanings
1584 */
1585int fdt_set_name(void *fdt, int nodeoffset, const char *name);
1586
1587/**
1588 * fdt_setprop - create or change a property
1589 * @fdt: pointer to the device tree blob
1590 * @nodeoffset: offset of the node whose property to change
1591 * @name: name of the property to change
1592 * @val: pointer to data to set the property value to
1593 * @len: length of the property value
1594 *
1595 * fdt_setprop() sets the value of the named property in the given
1596 * node to the given value and length, creating the property if it
1597 * does not already exist.
1598 *
1599 * This function may insert or delete data from the blob, and will
1600 * therefore change the offsets of some existing nodes.
1601 *
1602 * returns:
1603 *      0, on success
1604 *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1605 *              contain the new property value
1606 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1607 *      -FDT_ERR_BADLAYOUT,
1608 *      -FDT_ERR_BADMAGIC,
1609 *      -FDT_ERR_BADVERSION,
1610 *      -FDT_ERR_BADSTATE,
1611 *      -FDT_ERR_BADSTRUCTURE,
1612 *      -FDT_ERR_BADLAYOUT,
1613 *      -FDT_ERR_TRUNCATED, standard meanings
1614 */
1615int fdt_setprop(void *fdt, int nodeoffset, const char *name,
1616                const void *val, int len);
1617
1618/**
1619 * fdt_setprop_placeholder - allocate space for a property
1620 * @fdt: pointer to the device tree blob
1621 * @nodeoffset: offset of the node whose property to change
1622 * @name: name of the property to change
1623 * @len: length of the property value
1624 * @prop_data: return pointer to property data
1625 *
1626 * fdt_setprop_placeholer() allocates the named property in the given node.
1627 * If the property exists it is resized. In either case a pointer to the
1628 * property data is returned.
1629 *
1630 * This function may insert or delete data from the blob, and will
1631 * therefore change the offsets of some existing nodes.
1632 *
1633 * returns:
1634 *      0, on success
1635 *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1636 *              contain the new property value
1637 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1638 *      -FDT_ERR_BADLAYOUT,
1639 *      -FDT_ERR_BADMAGIC,
1640 *      -FDT_ERR_BADVERSION,
1641 *      -FDT_ERR_BADSTATE,
1642 *      -FDT_ERR_BADSTRUCTURE,
1643 *      -FDT_ERR_BADLAYOUT,
1644 *      -FDT_ERR_TRUNCATED, standard meanings
1645 */
1646int fdt_setprop_placeholder(void *fdt, int nodeoffset, const char *name,
1647                            int len, void **prop_data);
1648
1649/**
1650 * fdt_setprop_u32 - set a property to a 32-bit integer
1651 * @fdt: pointer to the device tree blob
1652 * @nodeoffset: offset of the node whose property to change
1653 * @name: name of the property to change
1654 * @val: 32-bit integer value for the property (native endian)
1655 *
1656 * fdt_setprop_u32() sets the value of the named property in the given
1657 * node to the given 32-bit integer value (converting to big-endian if
1658 * necessary), or creates a new property with that value if it does
1659 * not already exist.
1660 *
1661 * This function may insert or delete data from the blob, and will
1662 * therefore change the offsets of some existing nodes.
1663 *
1664 * returns:
1665 *      0, on success
1666 *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1667 *              contain the new property value
1668 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1669 *      -FDT_ERR_BADLAYOUT,
1670 *      -FDT_ERR_BADMAGIC,
1671 *      -FDT_ERR_BADVERSION,
1672 *      -FDT_ERR_BADSTATE,
1673 *      -FDT_ERR_BADSTRUCTURE,
1674 *      -FDT_ERR_BADLAYOUT,
1675 *      -FDT_ERR_TRUNCATED, standard meanings
1676 */
1677static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
1678                                  uint32_t val)
1679{
1680        fdt32_t tmp = cpu_to_fdt32(val);
1681        return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1682}
1683
1684/**
1685 * fdt_setprop_u64 - set a property to a 64-bit integer
1686 * @fdt: pointer to the device tree blob
1687 * @nodeoffset: offset of the node whose property to change
1688 * @name: name of the property to change
1689 * @val: 64-bit integer value for the property (native endian)
1690 *
1691 * fdt_setprop_u64() sets the value of the named property in the given
1692 * node to the given 64-bit integer value (converting to big-endian if
1693 * necessary), or creates a new property with that value if it does
1694 * not already exist.
1695 *
1696 * This function may insert or delete data from the blob, and will
1697 * therefore change the offsets of some existing nodes.
1698 *
1699 * returns:
1700 *      0, on success
1701 *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1702 *              contain the new property value
1703 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1704 *      -FDT_ERR_BADLAYOUT,
1705 *      -FDT_ERR_BADMAGIC,
1706 *      -FDT_ERR_BADVERSION,
1707 *      -FDT_ERR_BADSTATE,
1708 *      -FDT_ERR_BADSTRUCTURE,
1709 *      -FDT_ERR_BADLAYOUT,
1710 *      -FDT_ERR_TRUNCATED, standard meanings
1711 */
1712static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
1713                                  uint64_t val)
1714{
1715        fdt64_t tmp = cpu_to_fdt64(val);
1716        return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1717}
1718
1719/**
1720 * fdt_setprop_cell - set a property to a single cell value
1721 * @fdt: pointer to the device tree blob
1722 * @nodeoffset: offset of the node whose property to change
1723 * @name: name of the property to change
1724 * @val: 32-bit integer value for the property (native endian)
1725 *
1726 * This is an alternative name for fdt_setprop_u32()
1727 *
1728 * Return: 0 on success, negative libfdt error value otherwise.
1729 */
1730static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
1731                                   uint32_t val)
1732{
1733        return fdt_setprop_u32(fdt, nodeoffset, name, val);
1734}
1735
1736/**
1737 * fdt_setprop_string - set a property to a string value
1738 * @fdt: pointer to the device tree blob
1739 * @nodeoffset: offset of the node whose property to change
1740 * @name: name of the property to change
1741 * @str: string value for the property
1742 *
1743 * fdt_setprop_string() sets the value of the named property in the
1744 * given node to the given string value (using the length of the
1745 * string to determine the new length of the property), or creates a
1746 * new property with that value if it does not already exist.
1747 *
1748 * This function may insert or delete data from the blob, and will
1749 * therefore change the offsets of some existing nodes.
1750 *
1751 * returns:
1752 *      0, on success
1753 *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1754 *              contain the new property value
1755 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1756 *      -FDT_ERR_BADLAYOUT,
1757 *      -FDT_ERR_BADMAGIC,
1758 *      -FDT_ERR_BADVERSION,
1759 *      -FDT_ERR_BADSTATE,
1760 *      -FDT_ERR_BADSTRUCTURE,
1761 *      -FDT_ERR_BADLAYOUT,
1762 *      -FDT_ERR_TRUNCATED, standard meanings
1763 */
1764#define fdt_setprop_string(fdt, nodeoffset, name, str) \
1765        fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1766
1767
1768/**
1769 * fdt_setprop_empty - set a property to an empty value
1770 * @fdt: pointer to the device tree blob
1771 * @nodeoffset: offset of the node whose property to change
1772 * @name: name of the property to change
1773 *
1774 * fdt_setprop_empty() sets the value of the named property in the
1775 * given node to an empty (zero length) value, or creates a new empty
1776 * property if it does not already exist.
1777 *
1778 * This function may insert or delete data from the blob, and will
1779 * therefore change the offsets of some existing nodes.
1780 *
1781 * returns:
1782 *      0, on success
1783 *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1784 *              contain the new property value
1785 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1786 *      -FDT_ERR_BADLAYOUT,
1787 *      -FDT_ERR_BADMAGIC,
1788 *      -FDT_ERR_BADVERSION,
1789 *      -FDT_ERR_BADSTATE,
1790 *      -FDT_ERR_BADSTRUCTURE,
1791 *      -FDT_ERR_BADLAYOUT,
1792 *      -FDT_ERR_TRUNCATED, standard meanings
1793 */
1794#define fdt_setprop_empty(fdt, nodeoffset, name) \
1795        fdt_setprop((fdt), (nodeoffset), (name), NULL, 0)
1796
1797/**
1798 * fdt_appendprop - append to or create a property
1799 * @fdt: pointer to the device tree blob
1800 * @nodeoffset: offset of the node whose property to change
1801 * @name: name of the property to append to
1802 * @val: pointer to data to append to the property value
1803 * @len: length of the data to append to the property value
1804 *
1805 * fdt_appendprop() appends the value to the named property in the
1806 * given node, creating the property if it does not already exist.
1807 *
1808 * This function may insert data into the blob, and will therefore
1809 * change the offsets of some existing nodes.
1810 *
1811 * returns:
1812 *      0, on success
1813 *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1814 *              contain the new property value
1815 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1816 *      -FDT_ERR_BADLAYOUT,
1817 *      -FDT_ERR_BADMAGIC,
1818 *      -FDT_ERR_BADVERSION,
1819 *      -FDT_ERR_BADSTATE,
1820 *      -FDT_ERR_BADSTRUCTURE,
1821 *      -FDT_ERR_BADLAYOUT,
1822 *      -FDT_ERR_TRUNCATED, standard meanings
1823 */
1824int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
1825                   const void *val, int len);
1826
1827/**
1828 * fdt_appendprop_u32 - append a 32-bit integer value to a property
1829 * @fdt: pointer to the device tree blob
1830 * @nodeoffset: offset of the node whose property to change
1831 * @name: name of the property to change
1832 * @val: 32-bit integer value to append to the property (native endian)
1833 *
1834 * fdt_appendprop_u32() appends the given 32-bit integer value
1835 * (converting to big-endian if necessary) to the value of the named
1836 * property in the given node, or creates a new property with that
1837 * value if it does not already exist.
1838 *
1839 * This function may insert data into the blob, and will therefore
1840 * change the offsets of some existing nodes.
1841 *
1842 * returns:
1843 *      0, on success
1844 *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1845 *              contain the new property value
1846 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1847 *      -FDT_ERR_BADLAYOUT,
1848 *      -FDT_ERR_BADMAGIC,
1849 *      -FDT_ERR_BADVERSION,
1850 *      -FDT_ERR_BADSTATE,
1851 *      -FDT_ERR_BADSTRUCTURE,
1852 *      -FDT_ERR_BADLAYOUT,
1853 *      -FDT_ERR_TRUNCATED, standard meanings
1854 */
1855static inline int fdt_appendprop_u32(void *fdt, int nodeoffset,
1856                                     const char *name, uint32_t val)
1857{
1858        fdt32_t tmp = cpu_to_fdt32(val);
1859        return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1860}
1861
1862/**
1863 * fdt_appendprop_u64 - append a 64-bit integer value to a property
1864 * @fdt: pointer to the device tree blob
1865 * @nodeoffset: offset of the node whose property to change
1866 * @name: name of the property to change
1867 * @val: 64-bit integer value to append to the property (native endian)
1868 *
1869 * fdt_appendprop_u64() appends the given 64-bit integer value
1870 * (converting to big-endian if necessary) to the value of the named
1871 * property in the given node, or creates a new property with that
1872 * value if it does not already exist.
1873 *
1874 * This function may insert data into the blob, and will therefore
1875 * change the offsets of some existing nodes.
1876 *
1877 * returns:
1878 *      0, on success
1879 *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1880 *              contain the new property value
1881 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1882 *      -FDT_ERR_BADLAYOUT,
1883 *      -FDT_ERR_BADMAGIC,
1884 *      -FDT_ERR_BADVERSION,
1885 *      -FDT_ERR_BADSTATE,
1886 *      -FDT_ERR_BADSTRUCTURE,
1887 *      -FDT_ERR_BADLAYOUT,
1888 *      -FDT_ERR_TRUNCATED, standard meanings
1889 */
1890static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
1891                                     const char *name, uint64_t val)
1892{
1893        fdt64_t tmp = cpu_to_fdt64(val);
1894        return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1895}
1896
1897/**
1898 * fdt_appendprop_cell - append a single cell value to a property
1899 * @fdt: pointer to the device tree blob
1900 * @nodeoffset: offset of the node whose property to change
1901 * @name: name of the property to change
1902 * @val: 32-bit integer value to append to the property (native endian)
1903 *
1904 * This is an alternative name for fdt_appendprop_u32()
1905 *
1906 * Return: 0 on success, negative libfdt error value otherwise.
1907 */
1908static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
1909                                      const char *name, uint32_t val)
1910{
1911        return fdt_appendprop_u32(fdt, nodeoffset, name, val);
1912}
1913
1914/**
1915 * fdt_appendprop_string - append a string to a property
1916 * @fdt: pointer to the device tree blob
1917 * @nodeoffset: offset of the node whose property to change
1918 * @name: name of the property to change
1919 * @str: string value to append to the property
1920 *
1921 * fdt_appendprop_string() appends the given string to the value of
1922 * the named property in the given node, or creates a new property
1923 * with that value if it does not already exist.
1924 *
1925 * This function may insert data into the blob, and will therefore
1926 * change the offsets of some existing nodes.
1927 *
1928 * returns:
1929 *      0, on success
1930 *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1931 *              contain the new property value
1932 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1933 *      -FDT_ERR_BADLAYOUT,
1934 *      -FDT_ERR_BADMAGIC,
1935 *      -FDT_ERR_BADVERSION,
1936 *      -FDT_ERR_BADSTATE,
1937 *      -FDT_ERR_BADSTRUCTURE,
1938 *      -FDT_ERR_BADLAYOUT,
1939 *      -FDT_ERR_TRUNCATED, standard meanings
1940 */
1941#define fdt_appendprop_string(fdt, nodeoffset, name, str) \
1942        fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1943
1944/**
1945 * fdt_appendprop_addrrange - append a address range property
1946 * @fdt: pointer to the device tree blob
1947 * @parent: offset of the parent node
1948 * @nodeoffset: offset of the node to add a property at
1949 * @name: name of property
1950 * @addr: start address of a given range
1951 * @size: size of a given range
1952 *
1953 * fdt_appendprop_addrrange() appends an address range value (start
1954 * address and size) to the value of the named property in the given
1955 * node, or creates a new property with that value if it does not
1956 * already exist.
1957 * If "name" is not specified, a default "reg" is used.
1958 * Cell sizes are determined by parent's #address-cells and #size-cells.
1959 *
1960 * This function may insert data into the blob, and will therefore
1961 * change the offsets of some existing nodes.
1962 *
1963 * returns:
1964 *      0, on success
1965 *      -FDT_ERR_BADLAYOUT,
1966 *      -FDT_ERR_BADMAGIC,
1967 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1968 *              #address-cells property
1969 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1970 *      -FDT_ERR_BADSTATE,
1971 *      -FDT_ERR_BADSTRUCTURE,
1972 *      -FDT_ERR_BADVERSION,
1973 *      -FDT_ERR_BADVALUE, addr or size doesn't fit to respective cells size
1974 *      -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1975 *              contain a new property
1976 *      -FDT_ERR_TRUNCATED, standard meanings
1977 */
1978int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
1979                             const char *name, uint64_t addr, uint64_t size);
1980
1981/**
1982 * fdt_delprop - delete a property
1983 * @fdt: pointer to the device tree blob
1984 * @nodeoffset: offset of the node whose property to nop
1985 * @name: name of the property to nop
1986 *
1987 * fdt_del_property() will delete the given property.
1988 *
1989 * This function will delete data from the blob, and will therefore
1990 * change the offsets of some existing nodes.
1991 *
1992 * returns:
1993 *      0, on success
1994 *      -FDT_ERR_NOTFOUND, node does not have the named property
1995 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1996 *      -FDT_ERR_BADLAYOUT,
1997 *      -FDT_ERR_BADMAGIC,
1998 *      -FDT_ERR_BADVERSION,
1999 *      -FDT_ERR_BADSTATE,
2000 *      -FDT_ERR_BADSTRUCTURE,
2001 *      -FDT_ERR_TRUNCATED, standard meanings
2002 */
2003int fdt_delprop(void *fdt, int nodeoffset, const char *name);
2004
2005/**
2006 * fdt_add_subnode_namelen - creates a new node based on substring
2007 * @fdt: pointer to the device tree blob
2008 * @parentoffset: structure block offset of a node
2009 * @name: name of the subnode to create
2010 * @namelen: number of characters of name to consider
2011 *
2012 * Identical to fdt_add_subnode(), but use only the first @namelen
2013 * characters of @name as the name of the new node.  This is useful for
2014 * creating subnodes based on a portion of a larger string, such as a
2015 * full path.
2016 *
2017 * Return: structure block offset of the created subnode (>=0),
2018 *         negative libfdt error value otherwise
2019 */
2020#ifndef SWIG /* Not available in Python */
2021int fdt_add_subnode_namelen(void *fdt, int parentoffset,
2022                            const char *name, int namelen);
2023#endif
2024
2025/**
2026 * fdt_add_subnode - creates a new node
2027 * @fdt: pointer to the device tree blob
2028 * @parentoffset: structure block offset of a node
2029 * @name: name of the subnode to locate
2030 *
2031 * fdt_add_subnode() creates a new node as a subnode of the node at
2032 * structure block offset parentoffset, with the given name (which
2033 * should include the unit address, if any).
2034 *
2035 * This function will insert data into the blob, and will therefore
2036 * change the offsets of some existing nodes.
2037 *
2038 * returns:
2039 *      structure block offset of the created nodeequested subnode (>=0), on
2040 *              success
2041 *      -FDT_ERR_NOTFOUND, if the requested subnode does not exist
2042 *      -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
2043 *              tag
2044 *      -FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
2045 *              the given name
2046 *      -FDT_ERR_NOSPACE, if there is insufficient free space in the
2047 *              blob to contain the new node
2048 *      -FDT_ERR_NOSPACE
2049 *      -FDT_ERR_BADLAYOUT
2050 *      -FDT_ERR_BADMAGIC,
2051 *      -FDT_ERR_BADVERSION,
2052 *      -FDT_ERR_BADSTATE,
2053 *      -FDT_ERR_BADSTRUCTURE,
2054 *      -FDT_ERR_TRUNCATED, standard meanings.
2055 */
2056int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
2057
2058/**
2059 * fdt_del_node - delete a node (subtree)
2060 * @fdt: pointer to the device tree blob
2061 * @nodeoffset: offset of the node to nop
2062 *
2063 * fdt_del_node() will remove the given node, including all its
2064 * subnodes if any, from the blob.
2065 *
2066 * This function will delete data from the blob, and will therefore
2067 * change the offsets of some existing nodes.
2068 *
2069 * returns:
2070 *      0, on success
2071 *      -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2072 *      -FDT_ERR_BADLAYOUT,
2073 *      -FDT_ERR_BADMAGIC,
2074 *      -FDT_ERR_BADVERSION,
2075 *      -FDT_ERR_BADSTATE,
2076 *      -FDT_ERR_BADSTRUCTURE,
2077 *      -FDT_ERR_TRUNCATED, standard meanings
2078 */
2079int fdt_del_node(void *fdt, int nodeoffset);
2080
2081/**
2082 * fdt_overlay_apply - Applies a DT overlay on a base DT
2083 * @fdt: pointer to the base device tree blob
2084 * @fdto: pointer to the device tree overlay blob
2085 *
2086 * fdt_overlay_apply() will apply the given device tree overlay on the
2087 * given base device tree.
2088 *
2089 * Expect the base device tree to be modified, even if the function
2090 * returns an error.
2091 *
2092 * returns:
2093 *      0, on success
2094 *      -FDT_ERR_NOSPACE, there's not enough space in the base device tree
2095 *      -FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
2096 *              properties in the base DT
2097 *      -FDT_ERR_BADPHANDLE,
2098 *      -FDT_ERR_BADOVERLAY,
2099 *      -FDT_ERR_NOPHANDLES,
2100 *      -FDT_ERR_INTERNAL,
2101 *      -FDT_ERR_BADLAYOUT,
2102 *      -FDT_ERR_BADMAGIC,
2103 *      -FDT_ERR_BADOFFSET,
2104 *      -FDT_ERR_BADPATH,
2105 *      -FDT_ERR_BADVERSION,
2106 *      -FDT_ERR_BADSTRUCTURE,
2107 *      -FDT_ERR_BADSTATE,
2108 *      -FDT_ERR_TRUNCATED, standard meanings
2109 */
2110int fdt_overlay_apply(void *fdt, void *fdto);
2111
2112/**********************************************************************/
2113/* Debugging / informational functions                                */
2114/**********************************************************************/
2115
2116const char *fdt_strerror(int errval);
2117
2118#ifdef __cplusplus
2119}
2120#endif
2121
2122#endif /* LIBFDT_H */
2123