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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 uint16_t fdt16_ld(const fdt16_t *p)
 135{
 136	const uint8_t *bp = (const uint8_t *)p;
 137
 138	return ((uint16_t)bp[0] << 8) | bp[1];
 139}
 140
 141static inline uint32_t fdt32_ld(const fdt32_t *p)
 142{
 143	const uint8_t *bp = (const uint8_t *)p;
 144
 145	return ((uint32_t)bp[0] << 24)
 146		| ((uint32_t)bp[1] << 16)
 147		| ((uint32_t)bp[2] << 8)
 148		| bp[3];
 149}
 150
 151static inline void fdt32_st(void *property, uint32_t value)
 152{
 153	uint8_t *bp = (uint8_t *)property;
 154
 155	bp[0] = value >> 24;
 156	bp[1] = (value >> 16) & 0xff;
 157	bp[2] = (value >> 8) & 0xff;
 158	bp[3] = value & 0xff;
 159}
 160
 161static inline uint64_t fdt64_ld(const fdt64_t *p)
 162{
 163	const uint8_t *bp = (const uint8_t *)p;
 164
 165	return ((uint64_t)bp[0] << 56)
 166		| ((uint64_t)bp[1] << 48)
 167		| ((uint64_t)bp[2] << 40)
 168		| ((uint64_t)bp[3] << 32)
 169		| ((uint64_t)bp[4] << 24)
 170		| ((uint64_t)bp[5] << 16)
 171		| ((uint64_t)bp[6] << 8)
 172		| bp[7];
 173}
 174
 175static inline void fdt64_st(void *property, uint64_t value)
 176{
 177	uint8_t *bp = (uint8_t *)property;
 178
 179	bp[0] = value >> 56;
 180	bp[1] = (value >> 48) & 0xff;
 181	bp[2] = (value >> 40) & 0xff;
 182	bp[3] = (value >> 32) & 0xff;
 183	bp[4] = (value >> 24) & 0xff;
 184	bp[5] = (value >> 16) & 0xff;
 185	bp[6] = (value >> 8) & 0xff;
 186	bp[7] = value & 0xff;
 187}
 188
 189/**********************************************************************/
 190/* Traversal functions                                                */
 191/**********************************************************************/
 192
 193int fdt_next_node(const void *fdt, int offset, int *depth);
 194
 195/**
 196 * fdt_first_subnode() - get offset of first direct subnode
 197 * @fdt:	FDT blob
 198 * @offset:	Offset of node to check
 199 *
 200 * Return: offset of first subnode, or -FDT_ERR_NOTFOUND if there is none
 201 */
 202int fdt_first_subnode(const void *fdt, int offset);
 203
 204/**
 205 * fdt_next_subnode() - get offset of next direct subnode
 206 * @fdt:	FDT blob
 207 * @offset:	Offset of previous subnode
 208 *
 209 * After first calling fdt_first_subnode(), call this function repeatedly to
 210 * get direct subnodes of a parent node.
 211 *
 212 * Return: offset of next subnode, or -FDT_ERR_NOTFOUND if there are no more
 213 *         subnodes
 214 */
 215int fdt_next_subnode(const void *fdt, int offset);
 216
 217/**
 218 * fdt_for_each_subnode - iterate over all subnodes of a parent
 219 *
 220 * @node:	child node (int, lvalue)
 221 * @fdt:	FDT blob (const void *)
 222 * @parent:	parent node (int)
 223 *
 224 * This is actually a wrapper around a for loop and would be used like so:
 225 *
 226 *	fdt_for_each_subnode(node, fdt, parent) {
 227 *		Use node
 228 *		...
 229 *	}
 230 *
 231 *	if ((node < 0) && (node != -FDT_ERR_NOTFOUND)) {
 232 *		Error handling
 233 *	}
 234 *
 235 * Note that this is implemented as a macro and @node is used as
 236 * iterator in the loop. The parent variable be constant or even a
 237 * literal.
 238 */
 239#define fdt_for_each_subnode(node, fdt, parent)		\
 240	for (node = fdt_first_subnode(fdt, parent);	\
 241	     node >= 0;					\
 242	     node = fdt_next_subnode(fdt, node))
 243
 244/**********************************************************************/
 245/* General functions                                                  */
 246/**********************************************************************/
 
 247#define fdt_get_header(fdt, field) \
 248	(fdt32_ld(&((const struct fdt_header *)(fdt))->field))
 249#define fdt_magic(fdt)			(fdt_get_header(fdt, magic))
 250#define fdt_totalsize(fdt)		(fdt_get_header(fdt, totalsize))
 251#define fdt_off_dt_struct(fdt)		(fdt_get_header(fdt, off_dt_struct))
 252#define fdt_off_dt_strings(fdt)		(fdt_get_header(fdt, off_dt_strings))
 253#define fdt_off_mem_rsvmap(fdt)		(fdt_get_header(fdt, off_mem_rsvmap))
 254#define fdt_version(fdt)		(fdt_get_header(fdt, version))
 255#define fdt_last_comp_version(fdt)	(fdt_get_header(fdt, last_comp_version))
 256#define fdt_boot_cpuid_phys(fdt)	(fdt_get_header(fdt, boot_cpuid_phys))
 257#define fdt_size_dt_strings(fdt)	(fdt_get_header(fdt, size_dt_strings))
 258#define fdt_size_dt_struct(fdt)		(fdt_get_header(fdt, size_dt_struct))
 259
 260#define fdt_set_hdr_(name) \
 261	static inline void fdt_set_##name(void *fdt, uint32_t val) \
 262	{ \
 263		struct fdt_header *fdth = (struct fdt_header *)fdt; \
 264		fdth->name = cpu_to_fdt32(val); \
 265	}
 266fdt_set_hdr_(magic);
 267fdt_set_hdr_(totalsize);
 268fdt_set_hdr_(off_dt_struct);
 269fdt_set_hdr_(off_dt_strings);
 270fdt_set_hdr_(off_mem_rsvmap);
 271fdt_set_hdr_(version);
 272fdt_set_hdr_(last_comp_version);
 273fdt_set_hdr_(boot_cpuid_phys);
 274fdt_set_hdr_(size_dt_strings);
 275fdt_set_hdr_(size_dt_struct);
 276#undef fdt_set_hdr_
 277
 278/**
 279 * fdt_header_size - return the size of the tree's header
 280 * @fdt: pointer to a flattened device tree
 281 *
 282 * Return: size of DTB header in bytes
 283 */
 284size_t fdt_header_size(const void *fdt);
 285
 286/**
 287 * fdt_header_size_ - internal function to get header size from a version number
 288 * @version: devicetree version number
 289 *
 290 * Return: size of DTB header in bytes
 291 */
 292size_t fdt_header_size_(uint32_t version);
 293
 294/**
 295 * fdt_check_header - sanity check a device tree header
 296 * @fdt: pointer to data which might be a flattened device tree
 297 *
 298 * fdt_check_header() checks that the given buffer contains what
 299 * appears to be a flattened device tree, and that the header contains
 300 * valid information (to the extent that can be determined from the
 301 * header alone).
 302 *
 303 * returns:
 304 *     0, if the buffer appears to contain a valid device tree
 305 *     -FDT_ERR_BADMAGIC,
 306 *     -FDT_ERR_BADVERSION,
 307 *     -FDT_ERR_BADSTATE,
 308 *     -FDT_ERR_TRUNCATED, standard meanings, as above
 309 */
 310int fdt_check_header(const void *fdt);
 311
 312/**
 313 * fdt_move - move a device tree around in memory
 314 * @fdt: pointer to the device tree to move
 315 * @buf: pointer to memory where the device is to be moved
 316 * @bufsize: size of the memory space at buf
 317 *
 318 * fdt_move() relocates, if possible, the device tree blob located at
 319 * fdt to the buffer at buf of size bufsize.  The buffer may overlap
 320 * with the existing device tree blob at fdt.  Therefore,
 321 *     fdt_move(fdt, fdt, fdt_totalsize(fdt))
 322 * should always succeed.
 323 *
 324 * returns:
 325 *     0, on success
 326 *     -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
 327 *     -FDT_ERR_BADMAGIC,
 328 *     -FDT_ERR_BADVERSION,
 329 *     -FDT_ERR_BADSTATE, standard meanings
 330 */
 331int fdt_move(const void *fdt, void *buf, int bufsize);
 332
 333/**********************************************************************/
 334/* Read-only functions                                                */
 335/**********************************************************************/
 336
 337int fdt_check_full(const void *fdt, size_t bufsize);
 338
 339/**
 340 * fdt_get_string - retrieve a string from the strings block of a device tree
 341 * @fdt: pointer to the device tree blob
 342 * @stroffset: offset of the string within the strings block (native endian)
 343 * @lenp: optional pointer to return the string's length
 344 *
 345 * fdt_get_string() retrieves a pointer to a single string from the
 346 * strings block of the device tree blob at fdt, and optionally also
 347 * returns the string's length in *lenp.
 348 *
 349 * returns:
 350 *     a pointer to the string, on success
 351 *     NULL, if stroffset is out of bounds, or doesn't point to a valid string
 352 */
 353const char *fdt_get_string(const void *fdt, int stroffset, int *lenp);
 354
 355/**
 356 * fdt_string - retrieve a string from the strings block of a device tree
 357 * @fdt: pointer to the device tree blob
 358 * @stroffset: offset of the string within the strings block (native endian)
 359 *
 360 * fdt_string() retrieves a pointer to a single string from the
 361 * strings block of the device tree blob at fdt.
 362 *
 363 * returns:
 364 *     a pointer to the string, on success
 365 *     NULL, if stroffset is out of bounds, or doesn't point to a valid string
 366 */
 367const char *fdt_string(const void *fdt, int stroffset);
 368
 369/**
 370 * fdt_find_max_phandle - find and return the highest phandle in a tree
 371 * @fdt: pointer to the device tree blob
 372 * @phandle: return location for the highest phandle value found in the tree
 373 *
 374 * fdt_find_max_phandle() finds the highest phandle value in the given device
 375 * tree. The value returned in @phandle is only valid if the function returns
 376 * success.
 377 *
 378 * returns:
 379 *     0 on success or a negative error code on failure
 380 */
 381int fdt_find_max_phandle(const void *fdt, uint32_t *phandle);
 382
 383/**
 384 * fdt_get_max_phandle - retrieves the highest phandle in a tree
 385 * @fdt: pointer to the device tree blob
 386 *
 387 * fdt_get_max_phandle retrieves the highest phandle in the given
 388 * device tree. This will ignore badly formatted phandles, or phandles
 389 * with a value of 0 or -1.
 390 *
 391 * This function is deprecated in favour of fdt_find_max_phandle().
 392 *
 393 * returns:
 394 *      the highest phandle on success
 395 *      0, if no phandle was found in the device tree
 396 *      -1, if an error occurred
 397 */
 398static inline uint32_t fdt_get_max_phandle(const void *fdt)
 399{
 400	uint32_t phandle;
 401	int err;
 402
 403	err = fdt_find_max_phandle(fdt, &phandle);
 404	if (err < 0)
 405		return (uint32_t)-1;
 406
 407	return phandle;
 408}
 409
 410/**
 411 * fdt_generate_phandle - return a new, unused phandle for a device tree blob
 412 * @fdt: pointer to the device tree blob
 413 * @phandle: return location for the new phandle
 414 *
 415 * Walks the device tree blob and looks for the highest phandle value. On
 416 * success, the new, unused phandle value (one higher than the previously
 417 * highest phandle value in the device tree blob) will be returned in the
 418 * @phandle parameter.
 419 *
 420 * Return: 0 on success or a negative error-code on failure
 421 */
 422int fdt_generate_phandle(const void *fdt, uint32_t *phandle);
 423
 424/**
 425 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
 426 * @fdt: pointer to the device tree blob
 427 *
 428 * Returns the number of entries in the device tree blob's memory
 429 * reservation map.  This does not include the terminating 0,0 entry
 430 * or any other (0,0) entries reserved for expansion.
 431 *
 432 * returns:
 433 *     the number of entries
 434 */
 435int fdt_num_mem_rsv(const void *fdt);
 436
 437/**
 438 * fdt_get_mem_rsv - retrieve one memory reserve map entry
 439 * @fdt: pointer to the device tree blob
 440 * @n: index of reserve map entry
 441 * @address: pointer to 64-bit variable to hold the start address
 442 * @size: pointer to 64-bit variable to hold the size of the entry
 443 *
 444 * On success, @address and @size will contain the address and size of
 445 * the n-th reserve map entry from the device tree blob, in
 446 * native-endian format.
 447 *
 448 * returns:
 449 *     0, on success
 450 *     -FDT_ERR_BADMAGIC,
 451 *     -FDT_ERR_BADVERSION,
 452 *     -FDT_ERR_BADSTATE, standard meanings
 453 */
 454int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
 455
 456/**
 457 * fdt_subnode_offset_namelen - find a subnode based on substring
 458 * @fdt: pointer to the device tree blob
 459 * @parentoffset: structure block offset of a node
 460 * @name: name of the subnode to locate
 461 * @namelen: number of characters of name to consider
 462 *
 463 * Identical to fdt_subnode_offset(), but only examine the first
 464 * namelen characters of name for matching the subnode name.  This is
 465 * useful for finding subnodes based on a portion of a larger string,
 466 * such as a full path.
 467 *
 468 * Return: offset of the subnode or -FDT_ERR_NOTFOUND if name not found.
 469 */
 470#ifndef SWIG /* Not available in Python */
 471int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
 472			       const char *name, int namelen);
 473#endif
 474/**
 475 * fdt_subnode_offset - find a subnode of a given node
 476 * @fdt: pointer to the device tree blob
 477 * @parentoffset: structure block offset of a node
 478 * @name: name of the subnode to locate
 479 *
 480 * fdt_subnode_offset() finds a subnode of the node at structure block
 481 * offset parentoffset with the given name.  name may include a unit
 482 * address, in which case fdt_subnode_offset() will find the subnode
 483 * with that unit address, or the unit address may be omitted, in
 484 * which case fdt_subnode_offset() will find an arbitrary subnode
 485 * whose name excluding unit address matches the given name.
 486 *
 487 * returns:
 488 *	structure block offset of the requested subnode (>=0), on success
 489 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
 490 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
 491 *		tag
 492 *	-FDT_ERR_BADMAGIC,
 493 *	-FDT_ERR_BADVERSION,
 494 *	-FDT_ERR_BADSTATE,
 495 *	-FDT_ERR_BADSTRUCTURE,
 496 *	-FDT_ERR_TRUNCATED, standard meanings.
 497 */
 498int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
 499
 500/**
 501 * fdt_path_offset_namelen - find a tree node by its full path
 502 * @fdt: pointer to the device tree blob
 503 * @path: full path of the node to locate
 504 * @namelen: number of characters of path to consider
 505 *
 506 * Identical to fdt_path_offset(), but only consider the first namelen
 507 * characters of path as the path name.
 508 *
 509 * Return: offset of the node or negative libfdt error value otherwise
 510 */
 511#ifndef SWIG /* Not available in Python */
 512int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen);
 513#endif
 514
 515/**
 516 * fdt_path_offset - find a tree node by its full path
 517 * @fdt: pointer to the device tree blob
 518 * @path: full path of the node to locate
 519 *
 520 * fdt_path_offset() finds a node of a given path in the device tree.
 521 * Each path component may omit the unit address portion, but the
 522 * results of this are undefined if any such path component is
 523 * ambiguous (that is if there are multiple nodes at the relevant
 524 * level matching the given component, differentiated only by unit
 525 * address).
 526 *
 527 * If the path is not absolute (i.e. does not begin with '/'), the
 528 * first component is treated as an alias.  That is, the property by
 529 * that name is looked up in the /aliases node, and the value of that
 530 * property used in place of that first component.
 531 *
 532 * For example, for this small fragment
 533 *
 534 * / {
 535 *     aliases {
 536 *         i2c2 = &foo; // RHS compiles to "/soc@0/i2c@30a40000/eeprom@52"
 537 *     };
 538 *     soc@0 {
 539 *         foo: i2c@30a40000 {
 540 *             bar: eeprom@52 {
 541 *             };
 542 *         };
 543 *     };
 544 * };
 545 *
 546 * these would be equivalent:
 547 *
 548 *   /soc@0/i2c@30a40000/eeprom@52
 549 *   i2c2/eeprom@52
 550 *
 551 * returns:
 552 *	structure block offset of the node with the requested path (>=0), on
 553 *		success
 554 *	-FDT_ERR_BADPATH, given path does not begin with '/' and the first
 555 *		component is not a valid alias
 556 *	-FDT_ERR_NOTFOUND, if the requested node does not exist
 557 *      -FDT_ERR_BADMAGIC,
 558 *	-FDT_ERR_BADVERSION,
 559 *	-FDT_ERR_BADSTATE,
 560 *	-FDT_ERR_BADSTRUCTURE,
 561 *	-FDT_ERR_TRUNCATED, standard meanings.
 562 */
 563int fdt_path_offset(const void *fdt, const char *path);
 564
 565/**
 566 * fdt_get_name - retrieve the name of a given node
 567 * @fdt: pointer to the device tree blob
 568 * @nodeoffset: structure block offset of the starting node
 569 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 570 *
 571 * fdt_get_name() retrieves the name (including unit address) of the
 572 * device tree node at structure block offset nodeoffset.  If lenp is
 573 * non-NULL, the length of this name is also returned, in the integer
 574 * pointed to by lenp.
 575 *
 576 * returns:
 577 *	pointer to the node's name, on success
 578 *		If lenp is non-NULL, *lenp contains the length of that name
 579 *			(>=0)
 580 *	NULL, on error
 581 *		if lenp is non-NULL *lenp contains an error code (<0):
 582 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
 583 *			tag
 584 *		-FDT_ERR_BADMAGIC,
 585 *		-FDT_ERR_BADVERSION,
 586 *		-FDT_ERR_BADSTATE, standard meanings
 587 */
 588const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
 589
 590/**
 591 * fdt_first_property_offset - find the offset of a node's first property
 592 * @fdt: pointer to the device tree blob
 593 * @nodeoffset: structure block offset of a node
 594 *
 595 * fdt_first_property_offset() finds the first property of the node at
 596 * the given structure block offset.
 597 *
 598 * returns:
 599 *	structure block offset of the property (>=0), on success
 600 *	-FDT_ERR_NOTFOUND, if the requested node has no properties
 601 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
 602 *      -FDT_ERR_BADMAGIC,
 603 *	-FDT_ERR_BADVERSION,
 604 *	-FDT_ERR_BADSTATE,
 605 *	-FDT_ERR_BADSTRUCTURE,
 606 *	-FDT_ERR_TRUNCATED, standard meanings.
 607 */
 608int fdt_first_property_offset(const void *fdt, int nodeoffset);
 609
 610/**
 611 * fdt_next_property_offset - step through a node's properties
 612 * @fdt: pointer to the device tree blob
 613 * @offset: structure block offset of a property
 614 *
 615 * fdt_next_property_offset() finds the property immediately after the
 616 * one at the given structure block offset.  This will be a property
 617 * of the same node as the given property.
 618 *
 619 * returns:
 620 *	structure block offset of the next property (>=0), on success
 621 *	-FDT_ERR_NOTFOUND, if the given property is the last in its node
 622 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag
 623 *      -FDT_ERR_BADMAGIC,
 624 *	-FDT_ERR_BADVERSION,
 625 *	-FDT_ERR_BADSTATE,
 626 *	-FDT_ERR_BADSTRUCTURE,
 627 *	-FDT_ERR_TRUNCATED, standard meanings.
 628 */
 629int fdt_next_property_offset(const void *fdt, int offset);
 630
 631/**
 632 * fdt_for_each_property_offset - iterate over all properties of a node
 633 *
 634 * @property:	property offset (int, lvalue)
 635 * @fdt:	FDT blob (const void *)
 636 * @node:	node offset (int)
 637 *
 638 * This is actually a wrapper around a for loop and would be used like so:
 639 *
 640 *	fdt_for_each_property_offset(property, fdt, node) {
 641 *		Use property
 642 *		...
 643 *	}
 644 *
 645 *	if ((property < 0) && (property != -FDT_ERR_NOTFOUND)) {
 646 *		Error handling
 647 *	}
 648 *
 649 * Note that this is implemented as a macro and property is used as
 650 * iterator in the loop. The node variable can be constant or even a
 651 * literal.
 652 */
 653#define fdt_for_each_property_offset(property, fdt, node)	\
 654	for (property = fdt_first_property_offset(fdt, node);	\
 655	     property >= 0;					\
 656	     property = fdt_next_property_offset(fdt, property))
 657
 658/**
 659 * fdt_get_property_by_offset - retrieve the property at a given offset
 660 * @fdt: pointer to the device tree blob
 661 * @offset: offset of the property to retrieve
 662 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 663 *
 664 * fdt_get_property_by_offset() retrieves a pointer to the
 665 * fdt_property structure within the device tree blob at the given
 666 * offset.  If lenp is non-NULL, the length of the property value is
 667 * also returned, in the integer pointed to by lenp.
 668 *
 669 * Note that this code only works on device tree versions >= 16. fdt_getprop()
 670 * works on all versions.
 671 *
 672 * returns:
 673 *	pointer to the structure representing the property
 674 *		if lenp is non-NULL, *lenp contains the length of the property
 675 *		value (>=0)
 676 *	NULL, on error
 677 *		if lenp is non-NULL, *lenp contains an error code (<0):
 678 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
 679 *		-FDT_ERR_BADMAGIC,
 680 *		-FDT_ERR_BADVERSION,
 681 *		-FDT_ERR_BADSTATE,
 682 *		-FDT_ERR_BADSTRUCTURE,
 683 *		-FDT_ERR_TRUNCATED, standard meanings
 684 */
 685const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
 686						      int offset,
 687						      int *lenp);
 688static inline struct fdt_property *fdt_get_property_by_offset_w(void *fdt,
 689								int offset,
 690								int *lenp)
 691{
 692	return (struct fdt_property *)(uintptr_t)
 693		fdt_get_property_by_offset(fdt, offset, lenp);
 694}
 695
 696/**
 697 * fdt_get_property_namelen - find a property based on substring
 698 * @fdt: pointer to the device tree blob
 699 * @nodeoffset: offset of the node whose property to find
 700 * @name: name of the property to find
 701 * @namelen: number of characters of name to consider
 702 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 703 *
 704 * Identical to fdt_get_property(), but only examine the first namelen
 705 * characters of name for matching the property name.
 706 *
 707 * Return: pointer to the structure representing the property, or NULL
 708 *         if not found
 709 */
 710#ifndef SWIG /* Not available in Python */
 711const struct fdt_property *fdt_get_property_namelen(const void *fdt,
 712						    int nodeoffset,
 713						    const char *name,
 714						    int namelen, int *lenp);
 715#endif
 716
 717/**
 718 * fdt_get_property - find a given property in a given node
 719 * @fdt: pointer to the device tree blob
 720 * @nodeoffset: offset of the node whose property to find
 721 * @name: name of the property to find
 722 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 723 *
 724 * fdt_get_property() retrieves a pointer to the fdt_property
 725 * structure within the device tree blob corresponding to the property
 726 * named 'name' of the node at offset nodeoffset.  If lenp is
 727 * non-NULL, the length of the property value is also returned, in the
 728 * integer pointed to by lenp.
 729 *
 730 * returns:
 731 *	pointer to the structure representing the property
 732 *		if lenp is non-NULL, *lenp contains the length of the property
 733 *		value (>=0)
 734 *	NULL, on error
 735 *		if lenp is non-NULL, *lenp contains an error code (<0):
 736 *		-FDT_ERR_NOTFOUND, node does not have named property
 737 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
 738 *			tag
 739 *		-FDT_ERR_BADMAGIC,
 740 *		-FDT_ERR_BADVERSION,
 741 *		-FDT_ERR_BADSTATE,
 742 *		-FDT_ERR_BADSTRUCTURE,
 743 *		-FDT_ERR_TRUNCATED, standard meanings
 744 */
 745const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
 746					    const char *name, int *lenp);
 747static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
 748						      const char *name,
 749						      int *lenp)
 750{
 751	return (struct fdt_property *)(uintptr_t)
 752		fdt_get_property(fdt, nodeoffset, name, lenp);
 753}
 754
 755/**
 756 * fdt_getprop_by_offset - retrieve the value of a property at a given offset
 757 * @fdt: pointer to the device tree blob
 758 * @offset: offset of the property to read
 759 * @namep: pointer to a string variable (will be overwritten) or NULL
 760 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 761 *
 762 * fdt_getprop_by_offset() retrieves a pointer to the value of the
 763 * property at structure block offset 'offset' (this will be a pointer
 764 * to within the device blob itself, not a copy of the value).  If
 765 * lenp is non-NULL, the length of the property value is also
 766 * returned, in the integer pointed to by lenp.  If namep is non-NULL,
 767 * the property's namne will also be returned in the char * pointed to
 768 * by namep (this will be a pointer to within the device tree's string
 769 * block, not a new copy of the name).
 770 *
 771 * returns:
 772 *	pointer to the property's value
 773 *		if lenp is non-NULL, *lenp contains the length of the property
 774 *		value (>=0)
 775 *		if namep is non-NULL *namep contiains a pointer to the property
 776 *		name.
 777 *	NULL, on error
 778 *		if lenp is non-NULL, *lenp contains an error code (<0):
 779 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
 780 *		-FDT_ERR_BADMAGIC,
 781 *		-FDT_ERR_BADVERSION,
 782 *		-FDT_ERR_BADSTATE,
 783 *		-FDT_ERR_BADSTRUCTURE,
 784 *		-FDT_ERR_TRUNCATED, standard meanings
 785 */
 786#ifndef SWIG /* This function is not useful in Python */
 787const void *fdt_getprop_by_offset(const void *fdt, int offset,
 788				  const char **namep, int *lenp);
 789#endif
 790
 791/**
 792 * fdt_getprop_namelen - get property value based on substring
 793 * @fdt: pointer to the device tree blob
 794 * @nodeoffset: offset of the node whose property to find
 795 * @name: name of the property to find
 796 * @namelen: number of characters of name to consider
 797 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 798 *
 799 * Identical to fdt_getprop(), but only examine the first namelen
 800 * characters of name for matching the property name.
 801 *
 802 * Return: pointer to the property's value or NULL on error
 803 */
 804#ifndef SWIG /* Not available in Python */
 805const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
 806				const char *name, int namelen, int *lenp);
 807static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset,
 808					  const char *name, int namelen,
 809					  int *lenp)
 810{
 811	return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name,
 812						      namelen, lenp);
 813}
 814#endif
 815
 816/**
 817 * fdt_getprop - retrieve the value of a given property
 818 * @fdt: pointer to the device tree blob
 819 * @nodeoffset: offset of the node whose property to find
 820 * @name: name of the property to find
 821 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 822 *
 823 * fdt_getprop() retrieves a pointer to the value of the property
 824 * named @name of the node at offset @nodeoffset (this will be a
 825 * pointer to within the device blob itself, not a copy of the value).
 826 * If @lenp is non-NULL, the length of the property value is also
 827 * returned, in the integer pointed to by @lenp.
 828 *
 829 * returns:
 830 *	pointer to the property's value
 831 *		if lenp is non-NULL, *lenp contains the length of the property
 832 *		value (>=0)
 833 *	NULL, on error
 834 *		if lenp is non-NULL, *lenp contains an error code (<0):
 835 *		-FDT_ERR_NOTFOUND, node does not have named property
 836 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
 837 *			tag
 838 *		-FDT_ERR_BADMAGIC,
 839 *		-FDT_ERR_BADVERSION,
 840 *		-FDT_ERR_BADSTATE,
 841 *		-FDT_ERR_BADSTRUCTURE,
 842 *		-FDT_ERR_TRUNCATED, standard meanings
 843 */
 844const void *fdt_getprop(const void *fdt, int nodeoffset,
 845			const char *name, int *lenp);
 846static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
 847				  const char *name, int *lenp)
 848{
 849	return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
 850}
 851
 852/**
 853 * fdt_get_phandle - retrieve the phandle of a given node
 854 * @fdt: pointer to the device tree blob
 855 * @nodeoffset: structure block offset of the node
 856 *
 857 * fdt_get_phandle() retrieves the phandle of the device tree node at
 858 * structure block offset nodeoffset.
 859 *
 860 * returns:
 861 *	the phandle of the node at nodeoffset, on success (!= 0, != -1)
 862 *	0, if the node has no phandle, or another error occurs
 863 */
 864uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
 865
 866/**
 867 * fdt_get_alias_namelen - get alias based on substring
 868 * @fdt: pointer to the device tree blob
 869 * @name: name of the alias th look up
 870 * @namelen: number of characters of name to consider
 871 *
 872 * Identical to fdt_get_alias(), but only examine the first @namelen
 873 * characters of @name for matching the alias name.
 874 *
 875 * Return: a pointer to the expansion of the alias named @name, if it exists,
 876 *	   NULL otherwise
 877 */
 878#ifndef SWIG /* Not available in Python */
 879const char *fdt_get_alias_namelen(const void *fdt,
 880				  const char *name, int namelen);
 881#endif
 882
 883/**
 884 * fdt_get_alias - retrieve the path referenced by a given alias
 885 * @fdt: pointer to the device tree blob
 886 * @name: name of the alias th look up
 887 *
 888 * fdt_get_alias() retrieves the value of a given alias.  That is, the
 889 * value of the property named @name in the node /aliases.
 890 *
 891 * returns:
 892 *	a pointer to the expansion of the alias named 'name', if it exists
 893 *	NULL, if the given alias or the /aliases node does not exist
 894 */
 895const char *fdt_get_alias(const void *fdt, const char *name);
 896
 897/**
 898 * fdt_get_symbol_namelen - get symbol based on substring
 899 * @fdt: pointer to the device tree blob
 900 * @name: name of the symbol to look up
 901 * @namelen: number of characters of name to consider
 902 *
 903 * Identical to fdt_get_symbol(), but only examine the first @namelen
 904 * characters of @name for matching the symbol name.
 905 *
 906 * Return: a pointer to the expansion of the symbol named @name, if it exists,
 907 *	   NULL otherwise
 908 */
 909#ifndef SWIG /* Not available in Python */
 910const char *fdt_get_symbol_namelen(const void *fdt,
 911				   const char *name, int namelen);
 912#endif
 913
 914/**
 915 * fdt_get_symbol - retrieve the path referenced by a given symbol
 916 * @fdt: pointer to the device tree blob
 917 * @name: name of the symbol to look up
 918 *
 919 * fdt_get_symbol() retrieves the value of a given symbol.  That is,
 920 * the value of the property named @name in the node
 921 * /__symbols__. Such a node exists only for a device tree blob that
 922 * has been compiled with the -@ dtc option. Each property corresponds
 923 * to a label appearing in the device tree source, with the name of
 924 * the property being the label and the value being the full path of
 925 * the node it is attached to.
 926 *
 927 * returns:
 928 *	a pointer to the expansion of the symbol named 'name', if it exists
 929 *	NULL, if the given symbol or the /__symbols__ node does not exist
 930 */
 931const char *fdt_get_symbol(const void *fdt, const char *name);
 932
 933/**
 934 * fdt_get_path - determine the full path of a node
 935 * @fdt: pointer to the device tree blob
 936 * @nodeoffset: offset of the node whose path to find
 937 * @buf: character buffer to contain the returned path (will be overwritten)
 938 * @buflen: size of the character buffer at buf
 939 *
 940 * fdt_get_path() computes the full path of the node at offset
 941 * nodeoffset, and records that path in the buffer at buf.
 942 *
 943 * NOTE: This function is expensive, as it must scan the device tree
 944 * structure from the start to nodeoffset.
 945 *
 946 * returns:
 947 *	0, on success
 948 *		buf contains the absolute path of the node at
 949 *		nodeoffset, as a NUL-terminated string.
 950 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 951 *	-FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
 952 *		characters and will not fit in the given buffer.
 953 *	-FDT_ERR_BADMAGIC,
 954 *	-FDT_ERR_BADVERSION,
 955 *	-FDT_ERR_BADSTATE,
 956 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 957 */
 958int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
 959
 960/**
 961 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
 962 * @fdt: pointer to the device tree blob
 963 * @nodeoffset: offset of the node whose parent to find
 964 * @supernodedepth: depth of the ancestor to find
 965 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
 966 *
 967 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
 968 * at a specific depth from the root (where the root itself has depth
 969 * 0, its immediate subnodes depth 1 and so forth).  So
 970 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
 971 * will always return 0, the offset of the root node.  If the node at
 972 * nodeoffset has depth D, then:
 973 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
 974 * will return nodeoffset itself.
 975 *
 976 * NOTE: This function is expensive, as it must scan the device tree
 977 * structure from the start to nodeoffset.
 978 *
 979 * returns:
 
 980 *	structure block offset of the node at node offset's ancestor
 981 *		of depth supernodedepth (>=0), on success
 982 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 983 *	-FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of
 984 *		nodeoffset
 985 *	-FDT_ERR_BADMAGIC,
 986 *	-FDT_ERR_BADVERSION,
 987 *	-FDT_ERR_BADSTATE,
 988 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 989 */
 990int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
 991				 int supernodedepth, int *nodedepth);
 992
 993/**
 994 * fdt_node_depth - find the depth of a given node
 995 * @fdt: pointer to the device tree blob
 996 * @nodeoffset: offset of the node whose parent to find
 997 *
 998 * fdt_node_depth() finds the depth of a given node.  The root node
 999 * has depth 0, its immediate subnodes depth 1 and so forth.
1000 *
1001 * NOTE: This function is expensive, as it must scan the device tree
1002 * structure from the start to nodeoffset.
1003 *
1004 * returns:
1005 *	depth of the node at nodeoffset (>=0), on success
1006 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1007 *	-FDT_ERR_BADMAGIC,
1008 *	-FDT_ERR_BADVERSION,
1009 *	-FDT_ERR_BADSTATE,
1010 *	-FDT_ERR_BADSTRUCTURE, standard meanings
1011 */
1012int fdt_node_depth(const void *fdt, int nodeoffset);
1013
1014/**
1015 * fdt_parent_offset - find the parent of a given node
1016 * @fdt: pointer to the device tree blob
1017 * @nodeoffset: offset of the node whose parent to find
1018 *
1019 * fdt_parent_offset() locates the parent node of a given node (that
1020 * is, it finds the offset of the node which contains the node at
1021 * nodeoffset as a subnode).
1022 *
1023 * NOTE: This function is expensive, as it must scan the device tree
1024 * structure from the start to nodeoffset, *twice*.
1025 *
1026 * returns:
1027 *	structure block offset of the parent of the node at nodeoffset
1028 *		(>=0), on success
1029 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1030 *	-FDT_ERR_BADMAGIC,
1031 *	-FDT_ERR_BADVERSION,
1032 *	-FDT_ERR_BADSTATE,
1033 *	-FDT_ERR_BADSTRUCTURE, standard meanings
1034 */
1035int fdt_parent_offset(const void *fdt, int nodeoffset);
1036
1037/**
1038 * fdt_node_offset_by_prop_value - find nodes with a given property value
1039 * @fdt: pointer to the device tree blob
1040 * @startoffset: only find nodes after this offset
1041 * @propname: property name to check
1042 * @propval: property value to search for
1043 * @proplen: length of the value in propval
1044 *
1045 * fdt_node_offset_by_prop_value() returns the offset of the first
1046 * node after startoffset, which has a property named propname whose
1047 * value is of length proplen and has value equal to propval; or if
1048 * startoffset is -1, the very first such node in the tree.
1049 *
1050 * To iterate through all nodes matching the criterion, the following
1051 * idiom can be used:
1052 *	offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
1053 *					       propval, proplen);
1054 *	while (offset != -FDT_ERR_NOTFOUND) {
1055 *		// other code here
1056 *		offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
1057 *						       propval, proplen);
1058 *	}
1059 *
1060 * Note the -1 in the first call to the function, if 0 is used here
1061 * instead, the function will never locate the root node, even if it
1062 * matches the criterion.
1063 *
1064 * returns:
1065 *	structure block offset of the located node (>= 0, >startoffset),
1066 *		 on success
1067 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
1068 *		tree after startoffset
1069 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1070 *	-FDT_ERR_BADMAGIC,
1071 *	-FDT_ERR_BADVERSION,
1072 *	-FDT_ERR_BADSTATE,
1073 *	-FDT_ERR_BADSTRUCTURE, standard meanings
1074 */
1075int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
1076				  const char *propname,
1077				  const void *propval, int proplen);
1078
1079/**
1080 * fdt_node_offset_by_phandle - find the node with a given phandle
1081 * @fdt: pointer to the device tree blob
1082 * @phandle: phandle value
1083 *
1084 * fdt_node_offset_by_phandle() returns the offset of the node
1085 * which has the given phandle value.  If there is more than one node
1086 * in the tree with the given phandle (an invalid tree), results are
1087 * undefined.
1088 *
1089 * returns:
1090 *	structure block offset of the located node (>= 0), on success
1091 *	-FDT_ERR_NOTFOUND, no node with that phandle exists
1092 *	-FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
1093 *	-FDT_ERR_BADMAGIC,
1094 *	-FDT_ERR_BADVERSION,
1095 *	-FDT_ERR_BADSTATE,
1096 *	-FDT_ERR_BADSTRUCTURE, standard meanings
1097 */
1098int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
1099
1100/**
1101 * fdt_node_check_compatible - check a node's compatible property
1102 * @fdt: pointer to the device tree blob
1103 * @nodeoffset: offset of a tree node
1104 * @compatible: string to match against
1105 *
 
1106 * fdt_node_check_compatible() returns 0 if the given node contains a
1107 * @compatible property with the given string as one of its elements,
1108 * it returns non-zero otherwise, or on error.
1109 *
1110 * returns:
1111 *	0, if the node has a 'compatible' property listing the given string
1112 *	1, if the node has a 'compatible' property, but it does not list
1113 *		the given string
1114 *	-FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
1115 *	-FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
1116 *	-FDT_ERR_BADMAGIC,
1117 *	-FDT_ERR_BADVERSION,
1118 *	-FDT_ERR_BADSTATE,
1119 *	-FDT_ERR_BADSTRUCTURE, standard meanings
1120 */
1121int fdt_node_check_compatible(const void *fdt, int nodeoffset,
1122			      const char *compatible);
1123
1124/**
1125 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
1126 * @fdt: pointer to the device tree blob
1127 * @startoffset: only find nodes after this offset
1128 * @compatible: 'compatible' string to match against
1129 *
1130 * fdt_node_offset_by_compatible() returns the offset of the first
1131 * node after startoffset, which has a 'compatible' property which
1132 * lists the given compatible string; or if startoffset is -1, the
1133 * very first such node in the tree.
1134 *
1135 * To iterate through all nodes matching the criterion, the following
1136 * idiom can be used:
1137 *	offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
1138 *	while (offset != -FDT_ERR_NOTFOUND) {
1139 *		// other code here
1140 *		offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
1141 *	}
1142 *
1143 * Note the -1 in the first call to the function, if 0 is used here
1144 * instead, the function will never locate the root node, even if it
1145 * matches the criterion.
1146 *
1147 * returns:
1148 *	structure block offset of the located node (>= 0, >startoffset),
1149 *		 on success
1150 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
1151 *		tree after startoffset
1152 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1153 *	-FDT_ERR_BADMAGIC,
1154 *	-FDT_ERR_BADVERSION,
1155 *	-FDT_ERR_BADSTATE,
1156 *	-FDT_ERR_BADSTRUCTURE, standard meanings
1157 */
1158int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
1159				  const char *compatible);
1160
1161/**
1162 * fdt_stringlist_contains - check a string list property for a string
1163 * @strlist: Property containing a list of strings to check
1164 * @listlen: Length of property
1165 * @str: String to search for
1166 *
1167 * This is a utility function provided for convenience. The list contains
1168 * one or more strings, each terminated by \0, as is found in a device tree
1169 * "compatible" property.
1170 *
1171 * Return: 1 if the string is found in the list, 0 not found, or invalid list
1172 */
1173int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
1174
1175/**
1176 * fdt_stringlist_count - count the number of strings in a string list
1177 * @fdt: pointer to the device tree blob
1178 * @nodeoffset: offset of a tree node
1179 * @property: name of the property containing the string list
1180 *
1181 * Return:
1182 *   the number of strings in the given property
1183 *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1184 *   -FDT_ERR_NOTFOUND if the property does not exist
1185 */
1186int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property);
1187
1188/**
1189 * fdt_stringlist_search - find a string in a string list and return its index
1190 * @fdt: pointer to the device tree blob
1191 * @nodeoffset: offset of a tree node
1192 * @property: name of the property containing the string list
1193 * @string: string to look up in the string list
1194 *
1195 * Note that it is possible for this function to succeed on property values
1196 * that are not NUL-terminated. That's because the function will stop after
1197 * finding the first occurrence of @string. This can for example happen with
1198 * small-valued cell properties, such as #address-cells, when searching for
1199 * the empty string.
1200 *
1201 * return:
1202 *   the index of the string in the list of strings
1203 *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1204 *   -FDT_ERR_NOTFOUND if the property does not exist or does not contain
1205 *                     the given string
1206 */
1207int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
1208			  const char *string);
1209
1210/**
1211 * fdt_stringlist_get() - obtain the string at a given index in a string list
1212 * @fdt: pointer to the device tree blob
1213 * @nodeoffset: offset of a tree node
1214 * @property: name of the property containing the string list
1215 * @index: index of the string to return
1216 * @lenp: return location for the string length or an error code on failure
1217 *
1218 * Note that this will successfully extract strings from properties with
1219 * non-NUL-terminated values. For example on small-valued cell properties
1220 * this function will return the empty string.
1221 *
1222 * If non-NULL, the length of the string (on success) or a negative error-code
1223 * (on failure) will be stored in the integer pointer to by lenp.
1224 *
1225 * Return:
1226 *   A pointer to the string at the given index in the string list or NULL on
1227 *   failure. On success the length of the string will be stored in the memory
1228 *   location pointed to by the lenp parameter, if non-NULL. On failure one of
1229 *   the following negative error codes will be returned in the lenp parameter
1230 *   (if non-NULL):
1231 *     -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1232 *     -FDT_ERR_NOTFOUND if the property does not exist
1233 */
1234const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
1235			       const char *property, int index,
1236			       int *lenp);
1237
1238/**********************************************************************/
1239/* Read-only functions (addressing related)                           */
1240/**********************************************************************/
1241
1242/**
1243 * FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells
1244 *
1245 * This is the maximum value for #address-cells, #size-cells and
1246 * similar properties that will be processed by libfdt.  IEE1275
1247 * requires that OF implementations handle values up to 4.
1248 * Implementations may support larger values, but in practice higher
1249 * values aren't used.
1250 */
1251#define FDT_MAX_NCELLS		4
1252
1253/**
1254 * fdt_address_cells - retrieve address size for a bus represented in the tree
1255 * @fdt: pointer to the device tree blob
1256 * @nodeoffset: offset of the node to find the address size for
1257 *
1258 * When the node has a valid #address-cells property, returns its value.
1259 *
1260 * returns:
1261 *	0 <= n < FDT_MAX_NCELLS, on success
1262 *      2, if the node has no #address-cells property
1263 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1264 *		#address-cells property
1265 *	-FDT_ERR_BADMAGIC,
1266 *	-FDT_ERR_BADVERSION,
1267 *	-FDT_ERR_BADSTATE,
1268 *	-FDT_ERR_BADSTRUCTURE,
1269 *	-FDT_ERR_TRUNCATED, standard meanings
1270 */
1271int fdt_address_cells(const void *fdt, int nodeoffset);
1272
1273/**
1274 * fdt_size_cells - retrieve address range size for a bus represented in the
1275 *                  tree
1276 * @fdt: pointer to the device tree blob
1277 * @nodeoffset: offset of the node to find the address range size for
1278 *
1279 * When the node has a valid #size-cells property, returns its value.
1280 *
1281 * returns:
1282 *	0 <= n < FDT_MAX_NCELLS, on success
1283 *      1, if the node has no #size-cells property
1284 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1285 *		#size-cells property
1286 *	-FDT_ERR_BADMAGIC,
1287 *	-FDT_ERR_BADVERSION,
1288 *	-FDT_ERR_BADSTATE,
1289 *	-FDT_ERR_BADSTRUCTURE,
1290 *	-FDT_ERR_TRUNCATED, standard meanings
1291 */
1292int fdt_size_cells(const void *fdt, int nodeoffset);
1293
1294
1295/**********************************************************************/
1296/* Write-in-place functions                                           */
1297/**********************************************************************/
1298
1299/**
1300 * fdt_setprop_inplace_namelen_partial - change a property's value,
1301 *                                       but not its size
1302 * @fdt: pointer to the device tree blob
1303 * @nodeoffset: offset of the node whose property to change
1304 * @name: name of the property to change
1305 * @namelen: number of characters of name to consider
1306 * @idx: index of the property to change in the array
1307 * @val: pointer to data to replace the property value with
1308 * @len: length of the property value
1309 *
1310 * Identical to fdt_setprop_inplace(), but modifies the given property
1311 * starting from the given index, and using only the first characters
1312 * of the name. It is useful when you want to manipulate only one value of
1313 * an array and you have a string that doesn't end with \0.
1314 *
1315 * Return: 0 on success, negative libfdt error value otherwise
1316 */
1317#ifndef SWIG /* Not available in Python */
1318int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
1319					const char *name, int namelen,
1320					uint32_t idx, const void *val,
1321					int len);
1322#endif
1323
1324/**
1325 * fdt_setprop_inplace - change a property's value, but not its size
1326 * @fdt: pointer to the device tree blob
1327 * @nodeoffset: offset of the node whose property to change
1328 * @name: name of the property to change
1329 * @val: pointer to data to replace the property value with
1330 * @len: length of the property value
1331 *
1332 * fdt_setprop_inplace() replaces the value of a given property with
1333 * the data in val, of length len.  This function cannot change the
1334 * size of a property, and so will only work if len is equal to the
1335 * current length of the property.
1336 *
1337 * This function will alter only the bytes in the blob which contain
1338 * the given property value, and will not alter or move any other part
1339 * of the tree.
1340 *
1341 * returns:
1342 *	0, on success
1343 *	-FDT_ERR_NOSPACE, if len is not equal to the property's current length
1344 *	-FDT_ERR_NOTFOUND, node does not have the named property
1345 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1346 *	-FDT_ERR_BADMAGIC,
1347 *	-FDT_ERR_BADVERSION,
1348 *	-FDT_ERR_BADSTATE,
1349 *	-FDT_ERR_BADSTRUCTURE,
1350 *	-FDT_ERR_TRUNCATED, standard meanings
1351 */
1352#ifndef SWIG /* Not available in Python */
1353int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
1354			const void *val, int len);
1355#endif
1356
1357/**
1358 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
1359 * @fdt: pointer to the device tree blob
1360 * @nodeoffset: offset of the node whose property to change
1361 * @name: name of the property to change
1362 * @val: 32-bit integer value to replace the property with
1363 *
1364 * fdt_setprop_inplace_u32() replaces the value of a given property
1365 * with the 32-bit integer value in val, converting val to big-endian
1366 * if necessary.  This function cannot change the size of a property,
1367 * and so will only work if the property already exists and has length
1368 * 4.
1369 *
1370 * This function will alter only the bytes in the blob which contain
1371 * the given property value, and will not alter or move any other part
1372 * of the tree.
1373 *
1374 * returns:
1375 *	0, on success
1376 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 4
1377 *	-FDT_ERR_NOTFOUND, node does not have the named property
1378 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1379 *	-FDT_ERR_BADMAGIC,
1380 *	-FDT_ERR_BADVERSION,
1381 *	-FDT_ERR_BADSTATE,
1382 *	-FDT_ERR_BADSTRUCTURE,
1383 *	-FDT_ERR_TRUNCATED, standard meanings
1384 */
1385static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
1386					  const char *name, uint32_t val)
1387{
1388	fdt32_t tmp = cpu_to_fdt32(val);
1389	return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1390}
1391
1392/**
1393 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
1394 * @fdt: pointer to the device tree blob
1395 * @nodeoffset: offset of the node whose property to change
1396 * @name: name of the property to change
1397 * @val: 64-bit integer value to replace the property with
1398 *
1399 * fdt_setprop_inplace_u64() replaces the value of a given property
1400 * with the 64-bit integer value in val, converting val to big-endian
1401 * if necessary.  This function cannot change the size of a property,
1402 * and so will only work if the property already exists and has length
1403 * 8.
1404 *
1405 * This function will alter only the bytes in the blob which contain
1406 * the given property value, and will not alter or move any other part
1407 * of the tree.
1408 *
1409 * returns:
1410 *	0, on success
1411 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 8
1412 *	-FDT_ERR_NOTFOUND, node does not have the named property
1413 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1414 *	-FDT_ERR_BADMAGIC,
1415 *	-FDT_ERR_BADVERSION,
1416 *	-FDT_ERR_BADSTATE,
1417 *	-FDT_ERR_BADSTRUCTURE,
1418 *	-FDT_ERR_TRUNCATED, standard meanings
1419 */
1420static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
1421					  const char *name, uint64_t val)
1422{
1423	fdt64_t tmp = cpu_to_fdt64(val);
1424	return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1425}
1426
1427/**
1428 * fdt_setprop_inplace_cell - change the value of a single-cell property
1429 * @fdt: pointer to the device tree blob
1430 * @nodeoffset: offset of the node containing the property
1431 * @name: name of the property to change the value of
1432 * @val: new value of the 32-bit cell
1433 *
1434 * This is an alternative name for fdt_setprop_inplace_u32()
1435 * Return: 0 on success, negative libfdt error number otherwise.
1436 */
1437static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
1438					   const char *name, uint32_t val)
1439{
1440	return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
 
1441}
1442
1443/**
1444 * fdt_nop_property - replace a property with nop tags
1445 * @fdt: pointer to the device tree blob
1446 * @nodeoffset: offset of the node whose property to nop
1447 * @name: name of the property to nop
1448 *
1449 * fdt_nop_property() will replace a given property's representation
1450 * in the blob with FDT_NOP tags, effectively removing it from the
1451 * tree.
1452 *
1453 * This function will alter only the bytes in the blob which contain
1454 * the property, and will not alter or move any other part of the
1455 * tree.
1456 *
1457 * returns:
1458 *	0, on success
1459 *	-FDT_ERR_NOTFOUND, node does not have the named property
1460 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1461 *	-FDT_ERR_BADMAGIC,
1462 *	-FDT_ERR_BADVERSION,
1463 *	-FDT_ERR_BADSTATE,
1464 *	-FDT_ERR_BADSTRUCTURE,
1465 *	-FDT_ERR_TRUNCATED, standard meanings
1466 */
1467int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
1468
1469/**
1470 * fdt_nop_node - replace a node (subtree) with nop tags
1471 * @fdt: pointer to the device tree blob
1472 * @nodeoffset: offset of the node to nop
1473 *
1474 * fdt_nop_node() will replace a given node's representation in the
1475 * blob, including all its subnodes, if any, with FDT_NOP tags,
1476 * effectively removing it from the tree.
1477 *
1478 * This function will alter only the bytes in the blob which contain
1479 * the node and its properties and subnodes, and will not alter or
1480 * move any other part of the tree.
1481 *
1482 * returns:
1483 *	0, on success
1484 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1485 *	-FDT_ERR_BADMAGIC,
1486 *	-FDT_ERR_BADVERSION,
1487 *	-FDT_ERR_BADSTATE,
1488 *	-FDT_ERR_BADSTRUCTURE,
1489 *	-FDT_ERR_TRUNCATED, standard meanings
1490 */
1491int fdt_nop_node(void *fdt, int nodeoffset);
1492
1493/**********************************************************************/
1494/* Sequential write functions                                         */
1495/**********************************************************************/
1496
1497/* fdt_create_with_flags flags */
1498#define FDT_CREATE_FLAG_NO_NAME_DEDUP 0x1
1499	/* FDT_CREATE_FLAG_NO_NAME_DEDUP: Do not try to de-duplicate property
1500	 * names in the fdt. This can result in faster creation times, but
1501	 * a larger fdt. */
1502
1503#define FDT_CREATE_FLAGS_ALL	(FDT_CREATE_FLAG_NO_NAME_DEDUP)
1504
1505/**
1506 * fdt_create_with_flags - begin creation of a new fdt
1507 * @buf: pointer to memory allocated where fdt will be created
1508 * @bufsize: size of the memory space at fdt
1509 * @flags: a valid combination of FDT_CREATE_FLAG_ flags, or 0.
1510 *
1511 * fdt_create_with_flags() begins the process of creating a new fdt with
1512 * the sequential write interface.
1513 *
1514 * fdt creation process must end with fdt_finish() to produce a valid fdt.
1515 *
1516 * returns:
1517 *	0, on success
1518 *	-FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1519 *	-FDT_ERR_BADFLAGS, flags is not valid
1520 */
1521int fdt_create_with_flags(void *buf, int bufsize, uint32_t flags);
1522
1523/**
1524 * fdt_create - begin creation of a new fdt
1525 * @buf: pointer to memory allocated where fdt will be created
1526 * @bufsize: size of the memory space at fdt
1527 *
1528 * fdt_create() is equivalent to fdt_create_with_flags() with flags=0.
1529 *
1530 * returns:
1531 *	0, on success
1532 *	-FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1533 */
1534int fdt_create(void *buf, int bufsize);
1535
1536int fdt_resize(void *fdt, void *buf, int bufsize);
1537int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
1538int fdt_finish_reservemap(void *fdt);
1539int fdt_begin_node(void *fdt, const char *name);
1540int fdt_property(void *fdt, const char *name, const void *val, int len);
1541static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
1542{
1543	fdt32_t tmp = cpu_to_fdt32(val);
1544	return fdt_property(fdt, name, &tmp, sizeof(tmp));
1545}
1546static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
1547{
1548	fdt64_t tmp = cpu_to_fdt64(val);
1549	return fdt_property(fdt, name, &tmp, sizeof(tmp));
1550}
1551
1552#ifndef SWIG /* Not available in Python */
1553static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
1554{
1555	return fdt_property_u32(fdt, name, val);
 
1556}
1557#endif
1558
1559/**
1560 * fdt_property_placeholder - add a new property and return a ptr to its value
1561 *
1562 * @fdt: pointer to the device tree blob
1563 * @name: name of property to add
1564 * @len: length of property value in bytes
1565 * @valp: returns a pointer to where where the value should be placed
1566 *
1567 * returns:
1568 *	0, on success
1569 *	-FDT_ERR_BADMAGIC,
1570 *	-FDT_ERR_NOSPACE, standard meanings
1571 */
1572int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp);
1573
1574#define fdt_property_string(fdt, name, str) \
1575	fdt_property(fdt, name, str, strlen(str)+1)
1576int fdt_end_node(void *fdt);
1577int fdt_finish(void *fdt);
1578
1579/**********************************************************************/
1580/* Read-write functions                                               */
1581/**********************************************************************/
1582
1583int fdt_create_empty_tree(void *buf, int bufsize);
1584int fdt_open_into(const void *fdt, void *buf, int bufsize);
1585int fdt_pack(void *fdt);
1586
1587/**
1588 * fdt_add_mem_rsv - add one memory reserve map entry
1589 * @fdt: pointer to the device tree blob
1590 * @address: 64-bit start address of the reserve map entry
1591 * @size: 64-bit size of the reserved region
1592 *
1593 * Adds a reserve map entry to the given blob reserving a region at
1594 * address address of length size.
1595 *
1596 * This function will insert data into the reserve map and will
1597 * therefore change the indexes of some entries in the table.
1598 *
1599 * returns:
1600 *	0, on success
1601 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1602 *		contain the new reservation entry
1603 *	-FDT_ERR_BADMAGIC,
1604 *	-FDT_ERR_BADVERSION,
1605 *	-FDT_ERR_BADSTATE,
1606 *	-FDT_ERR_BADSTRUCTURE,
1607 *	-FDT_ERR_BADLAYOUT,
1608 *	-FDT_ERR_TRUNCATED, standard meanings
1609 */
1610int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
1611
1612/**
1613 * fdt_del_mem_rsv - remove a memory reserve map entry
1614 * @fdt: pointer to the device tree blob
1615 * @n: entry to remove
1616 *
1617 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
1618 * the blob.
1619 *
1620 * This function will delete data from the reservation table and will
1621 * therefore change the indexes of some entries in the table.
1622 *
1623 * returns:
1624 *	0, on success
1625 *	-FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
1626 *		are less than n+1 reserve map entries)
1627 *	-FDT_ERR_BADMAGIC,
1628 *	-FDT_ERR_BADVERSION,
1629 *	-FDT_ERR_BADSTATE,
1630 *	-FDT_ERR_BADSTRUCTURE,
1631 *	-FDT_ERR_BADLAYOUT,
1632 *	-FDT_ERR_TRUNCATED, standard meanings
1633 */
1634int fdt_del_mem_rsv(void *fdt, int n);
1635
1636/**
1637 * fdt_set_name - change the name of a given node
1638 * @fdt: pointer to the device tree blob
1639 * @nodeoffset: structure block offset of a node
1640 * @name: name to give the node
1641 *
1642 * fdt_set_name() replaces the name (including unit address, if any)
1643 * of the given node with the given string.  NOTE: this function can't
1644 * efficiently check if the new name is unique amongst the given
1645 * node's siblings; results are undefined if this function is invoked
1646 * with a name equal to one of the given node's siblings.
1647 *
1648 * This function may insert or delete data from the blob, and will
1649 * therefore change the offsets of some existing nodes.
1650 *
1651 * returns:
1652 *	0, on success
1653 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob
1654 *		to contain the new name
1655 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1656 *	-FDT_ERR_BADMAGIC,
1657 *	-FDT_ERR_BADVERSION,
1658 *	-FDT_ERR_BADSTATE, standard meanings
1659 */
1660int fdt_set_name(void *fdt, int nodeoffset, const char *name);
1661
1662/**
1663 * fdt_setprop - create or change a property
1664 * @fdt: pointer to the device tree blob
1665 * @nodeoffset: offset of the node whose property to change
1666 * @name: name of the property to change
1667 * @val: pointer to data to set the property value to
1668 * @len: length of the property value
1669 *
1670 * fdt_setprop() sets the value of the named property in the given
1671 * node to the given value and length, creating the property if it
1672 * does not already exist.
1673 *
1674 * This function may insert or delete data from the blob, and will
1675 * therefore change the offsets of some existing nodes.
1676 *
1677 * returns:
1678 *	0, on success
1679 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1680 *		contain the new property value
1681 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1682 *	-FDT_ERR_BADLAYOUT,
1683 *	-FDT_ERR_BADMAGIC,
1684 *	-FDT_ERR_BADVERSION,
1685 *	-FDT_ERR_BADSTATE,
1686 *	-FDT_ERR_BADSTRUCTURE,
1687 *	-FDT_ERR_BADLAYOUT,
1688 *	-FDT_ERR_TRUNCATED, standard meanings
1689 */
1690int fdt_setprop(void *fdt, int nodeoffset, const char *name,
1691		const void *val, int len);
1692
1693/**
1694 * fdt_setprop_placeholder - allocate space for a property
1695 * @fdt: pointer to the device tree blob
1696 * @nodeoffset: offset of the node whose property to change
1697 * @name: name of the property to change
1698 * @len: length of the property value
1699 * @prop_data: return pointer to property data
1700 *
1701 * fdt_setprop_placeholer() allocates the named property in the given node.
1702 * If the property exists it is resized. In either case a pointer to the
1703 * property data is returned.
1704 *
1705 * This function may insert or delete data from the blob, and will
1706 * therefore change the offsets of some existing nodes.
1707 *
1708 * returns:
1709 *	0, on success
1710 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1711 *		contain the new property value
1712 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1713 *	-FDT_ERR_BADLAYOUT,
1714 *	-FDT_ERR_BADMAGIC,
1715 *	-FDT_ERR_BADVERSION,
1716 *	-FDT_ERR_BADSTATE,
1717 *	-FDT_ERR_BADSTRUCTURE,
1718 *	-FDT_ERR_BADLAYOUT,
1719 *	-FDT_ERR_TRUNCATED, standard meanings
1720 */
1721int fdt_setprop_placeholder(void *fdt, int nodeoffset, const char *name,
1722			    int len, void **prop_data);
1723
1724/**
1725 * fdt_setprop_u32 - set a property to a 32-bit integer
1726 * @fdt: pointer to the device tree blob
1727 * @nodeoffset: offset of the node whose property to change
1728 * @name: name of the property to change
1729 * @val: 32-bit integer value for the property (native endian)
1730 *
1731 * fdt_setprop_u32() sets the value of the named property in the given
1732 * node to the given 32-bit integer value (converting to big-endian if
1733 * necessary), or creates a new property with that value if it does
1734 * not already exist.
1735 *
1736 * This function may insert or delete data from the blob, and will
1737 * therefore change the offsets of some existing nodes.
1738 *
1739 * returns:
1740 *	0, on success
1741 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1742 *		contain the new property value
1743 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1744 *	-FDT_ERR_BADLAYOUT,
1745 *	-FDT_ERR_BADMAGIC,
1746 *	-FDT_ERR_BADVERSION,
1747 *	-FDT_ERR_BADSTATE,
1748 *	-FDT_ERR_BADSTRUCTURE,
1749 *	-FDT_ERR_BADLAYOUT,
1750 *	-FDT_ERR_TRUNCATED, standard meanings
1751 */
1752static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
1753				  uint32_t val)
1754{
1755	fdt32_t tmp = cpu_to_fdt32(val);
1756	return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1757}
1758
1759/**
1760 * fdt_setprop_u64 - set a property to a 64-bit integer
1761 * @fdt: pointer to the device tree blob
1762 * @nodeoffset: offset of the node whose property to change
1763 * @name: name of the property to change
1764 * @val: 64-bit integer value for the property (native endian)
1765 *
1766 * fdt_setprop_u64() sets the value of the named property in the given
1767 * node to the given 64-bit integer value (converting to big-endian if
1768 * necessary), or creates a new property with that value if it does
1769 * not already exist.
1770 *
1771 * This function may insert or delete data from the blob, and will
1772 * therefore change the offsets of some existing nodes.
1773 *
1774 * returns:
1775 *	0, on success
1776 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1777 *		contain the new property value
1778 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1779 *	-FDT_ERR_BADLAYOUT,
1780 *	-FDT_ERR_BADMAGIC,
1781 *	-FDT_ERR_BADVERSION,
1782 *	-FDT_ERR_BADSTATE,
1783 *	-FDT_ERR_BADSTRUCTURE,
1784 *	-FDT_ERR_BADLAYOUT,
1785 *	-FDT_ERR_TRUNCATED, standard meanings
1786 */
1787static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
1788				  uint64_t val)
1789{
1790	fdt64_t tmp = cpu_to_fdt64(val);
1791	return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1792}
1793
1794/**
1795 * fdt_setprop_cell - set a property to a single cell value
1796 * @fdt: pointer to the device tree blob
1797 * @nodeoffset: offset of the node whose property to change
1798 * @name: name of the property to change
1799 * @val: 32-bit integer value for the property (native endian)
1800 *
1801 * This is an alternative name for fdt_setprop_u32()
1802 *
1803 * Return: 0 on success, negative libfdt error value otherwise.
1804 */
1805static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
1806				   uint32_t val)
1807{
1808	return fdt_setprop_u32(fdt, nodeoffset, name, val);
 
1809}
1810
1811/**
1812 * fdt_setprop_string - set a property to a string value
1813 * @fdt: pointer to the device tree blob
1814 * @nodeoffset: offset of the node whose property to change
1815 * @name: name of the property to change
1816 * @str: string value for the property
1817 *
1818 * fdt_setprop_string() sets the value of the named property in the
1819 * given node to the given string value (using the length of the
1820 * string to determine the new length of the property), or creates a
1821 * new property with that value if it does not already exist.
1822 *
1823 * This function may insert or delete data from the blob, and will
1824 * therefore change the offsets of some existing nodes.
1825 *
1826 * returns:
1827 *	0, on success
1828 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1829 *		contain the new property value
1830 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1831 *	-FDT_ERR_BADLAYOUT,
1832 *	-FDT_ERR_BADMAGIC,
1833 *	-FDT_ERR_BADVERSION,
1834 *	-FDT_ERR_BADSTATE,
1835 *	-FDT_ERR_BADSTRUCTURE,
1836 *	-FDT_ERR_BADLAYOUT,
1837 *	-FDT_ERR_TRUNCATED, standard meanings
1838 */
1839#define fdt_setprop_string(fdt, nodeoffset, name, str) \
1840	fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1841
1842
1843/**
1844 * fdt_setprop_empty - set a property to an empty value
1845 * @fdt: pointer to the device tree blob
1846 * @nodeoffset: offset of the node whose property to change
1847 * @name: name of the property to change
1848 *
1849 * fdt_setprop_empty() sets the value of the named property in the
1850 * given node to an empty (zero length) value, or creates a new empty
1851 * property if it does not already exist.
1852 *
1853 * This function may insert or delete data from the blob, and will
1854 * therefore change the offsets of some existing nodes.
1855 *
1856 * returns:
1857 *	0, on success
1858 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1859 *		contain the new property value
1860 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1861 *	-FDT_ERR_BADLAYOUT,
1862 *	-FDT_ERR_BADMAGIC,
1863 *	-FDT_ERR_BADVERSION,
1864 *	-FDT_ERR_BADSTATE,
1865 *	-FDT_ERR_BADSTRUCTURE,
1866 *	-FDT_ERR_BADLAYOUT,
1867 *	-FDT_ERR_TRUNCATED, standard meanings
1868 */
1869#define fdt_setprop_empty(fdt, nodeoffset, name) \
1870	fdt_setprop((fdt), (nodeoffset), (name), NULL, 0)
1871
1872/**
1873 * fdt_appendprop - append to or create a property
1874 * @fdt: pointer to the device tree blob
1875 * @nodeoffset: offset of the node whose property to change
1876 * @name: name of the property to append to
1877 * @val: pointer to data to append to the property value
1878 * @len: length of the data to append to the property value
1879 *
1880 * fdt_appendprop() appends the value to the named property in the
1881 * given node, creating the property if it does not already exist.
1882 *
1883 * This function may insert data into the blob, and will therefore
1884 * change the offsets of some existing nodes.
1885 *
1886 * returns:
1887 *	0, on success
1888 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1889 *		contain the new property value
1890 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1891 *	-FDT_ERR_BADLAYOUT,
1892 *	-FDT_ERR_BADMAGIC,
1893 *	-FDT_ERR_BADVERSION,
1894 *	-FDT_ERR_BADSTATE,
1895 *	-FDT_ERR_BADSTRUCTURE,
1896 *	-FDT_ERR_BADLAYOUT,
1897 *	-FDT_ERR_TRUNCATED, standard meanings
1898 */
1899int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
1900		   const void *val, int len);
1901
1902/**
1903 * fdt_appendprop_u32 - append a 32-bit integer value to a property
1904 * @fdt: pointer to the device tree blob
1905 * @nodeoffset: offset of the node whose property to change
1906 * @name: name of the property to change
1907 * @val: 32-bit integer value to append to the property (native endian)
1908 *
1909 * fdt_appendprop_u32() appends the given 32-bit integer value
1910 * (converting to big-endian if necessary) to the value of the named
1911 * property in the given node, or creates a new property with that
1912 * value if it does not already exist.
1913 *
1914 * This function may insert data into the blob, and will therefore
1915 * change the offsets of some existing nodes.
1916 *
1917 * returns:
1918 *	0, on success
1919 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1920 *		contain the new property value
1921 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1922 *	-FDT_ERR_BADLAYOUT,
1923 *	-FDT_ERR_BADMAGIC,
1924 *	-FDT_ERR_BADVERSION,
1925 *	-FDT_ERR_BADSTATE,
1926 *	-FDT_ERR_BADSTRUCTURE,
1927 *	-FDT_ERR_BADLAYOUT,
1928 *	-FDT_ERR_TRUNCATED, standard meanings
1929 */
1930static inline int fdt_appendprop_u32(void *fdt, int nodeoffset,
1931				     const char *name, uint32_t val)
1932{
1933	fdt32_t tmp = cpu_to_fdt32(val);
1934	return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1935}
1936
1937/**
1938 * fdt_appendprop_u64 - append a 64-bit integer value to a property
1939 * @fdt: pointer to the device tree blob
1940 * @nodeoffset: offset of the node whose property to change
1941 * @name: name of the property to change
1942 * @val: 64-bit integer value to append to the property (native endian)
1943 *
1944 * fdt_appendprop_u64() appends the given 64-bit integer value
1945 * (converting to big-endian if necessary) to the value of the named
1946 * property in the given node, or creates a new property with that
1947 * value if it does not already exist.
1948 *
1949 * This function may insert data into the blob, and will therefore
1950 * change the offsets of some existing nodes.
1951 *
1952 * returns:
1953 *	0, on success
1954 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1955 *		contain the new property value
1956 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1957 *	-FDT_ERR_BADLAYOUT,
1958 *	-FDT_ERR_BADMAGIC,
1959 *	-FDT_ERR_BADVERSION,
1960 *	-FDT_ERR_BADSTATE,
1961 *	-FDT_ERR_BADSTRUCTURE,
1962 *	-FDT_ERR_BADLAYOUT,
1963 *	-FDT_ERR_TRUNCATED, standard meanings
1964 */
1965static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
1966				     const char *name, uint64_t val)
1967{
1968	fdt64_t tmp = cpu_to_fdt64(val);
1969	return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1970}
1971
1972/**
1973 * fdt_appendprop_cell - append a single cell value to a property
1974 * @fdt: pointer to the device tree blob
1975 * @nodeoffset: offset of the node whose property to change
1976 * @name: name of the property to change
1977 * @val: 32-bit integer value to append to the property (native endian)
1978 *
1979 * This is an alternative name for fdt_appendprop_u32()
1980 *
1981 * Return: 0 on success, negative libfdt error value otherwise.
1982 */
1983static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
1984				      const char *name, uint32_t val)
1985{
1986	return fdt_appendprop_u32(fdt, nodeoffset, name, val);
1987}
1988
1989/**
1990 * fdt_appendprop_string - append a string to a property
1991 * @fdt: pointer to the device tree blob
1992 * @nodeoffset: offset of the node whose property to change
1993 * @name: name of the property to change
1994 * @str: string value to append to the property
1995 *
1996 * fdt_appendprop_string() appends the given string to the value of
1997 * the named property in the given node, or creates a new property
1998 * with that value if it does not already exist.
1999 *
2000 * This function may insert data into the blob, and will therefore
2001 * change the offsets of some existing nodes.
2002 *
2003 * returns:
2004 *	0, on success
2005 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
2006 *		contain the new property value
2007 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2008 *	-FDT_ERR_BADLAYOUT,
2009 *	-FDT_ERR_BADMAGIC,
2010 *	-FDT_ERR_BADVERSION,
2011 *	-FDT_ERR_BADSTATE,
2012 *	-FDT_ERR_BADSTRUCTURE,
2013 *	-FDT_ERR_BADLAYOUT,
2014 *	-FDT_ERR_TRUNCATED, standard meanings
2015 */
2016#define fdt_appendprop_string(fdt, nodeoffset, name, str) \
2017	fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
2018
2019/**
2020 * fdt_appendprop_addrrange - append a address range property
2021 * @fdt: pointer to the device tree blob
2022 * @parent: offset of the parent node
2023 * @nodeoffset: offset of the node to add a property at
2024 * @name: name of property
2025 * @addr: start address of a given range
2026 * @size: size of a given range
2027 *
2028 * fdt_appendprop_addrrange() appends an address range value (start
2029 * address and size) to the value of the named property in the given
2030 * node, or creates a new property with that value if it does not
2031 * already exist.
2032 *
2033 * Cell sizes are determined by parent's #address-cells and #size-cells.
2034 *
2035 * This function may insert data into the blob, and will therefore
2036 * change the offsets of some existing nodes.
2037 *
2038 * returns:
2039 *	0, on success
2040 *	-FDT_ERR_BADLAYOUT,
2041 *	-FDT_ERR_BADMAGIC,
2042 *	-FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
2043 *		#address-cells property
2044 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2045 *	-FDT_ERR_BADSTATE,
2046 *	-FDT_ERR_BADSTRUCTURE,
2047 *	-FDT_ERR_BADVERSION,
2048 *	-FDT_ERR_BADVALUE, addr or size doesn't fit to respective cells size
2049 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
2050 *		contain a new property
2051 *	-FDT_ERR_TRUNCATED, standard meanings
2052 */
2053int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
2054			     const char *name, uint64_t addr, uint64_t size);
2055
2056/**
2057 * fdt_delprop - delete a property
2058 * @fdt: pointer to the device tree blob
2059 * @nodeoffset: offset of the node whose property to nop
2060 * @name: name of the property to nop
2061 *
2062 * fdt_del_property() will delete the given property.
2063 *
2064 * This function will delete data from the blob, and will therefore
2065 * change the offsets of some existing nodes.
2066 *
2067 * returns:
2068 *	0, on success
2069 *	-FDT_ERR_NOTFOUND, node does not have the named property
2070 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2071 *	-FDT_ERR_BADLAYOUT,
2072 *	-FDT_ERR_BADMAGIC,
2073 *	-FDT_ERR_BADVERSION,
2074 *	-FDT_ERR_BADSTATE,
2075 *	-FDT_ERR_BADSTRUCTURE,
2076 *	-FDT_ERR_TRUNCATED, standard meanings
2077 */
2078int fdt_delprop(void *fdt, int nodeoffset, const char *name);
2079
2080/**
2081 * fdt_add_subnode_namelen - creates a new node based on substring
2082 * @fdt: pointer to the device tree blob
2083 * @parentoffset: structure block offset of a node
2084 * @name: name of the subnode to create
2085 * @namelen: number of characters of name to consider
2086 *
2087 * Identical to fdt_add_subnode(), but use only the first @namelen
2088 * characters of @name as the name of the new node.  This is useful for
2089 * creating subnodes based on a portion of a larger string, such as a
2090 * full path.
2091 *
2092 * Return: structure block offset of the created subnode (>=0),
2093 *	   negative libfdt error value otherwise
2094 */
2095#ifndef SWIG /* Not available in Python */
2096int fdt_add_subnode_namelen(void *fdt, int parentoffset,
2097			    const char *name, int namelen);
2098#endif
2099
2100/**
2101 * fdt_add_subnode - creates a new node
2102 * @fdt: pointer to the device tree blob
2103 * @parentoffset: structure block offset of a node
2104 * @name: name of the subnode to locate
2105 *
2106 * fdt_add_subnode() creates a new node as a subnode of the node at
2107 * structure block offset parentoffset, with the given name (which
2108 * should include the unit address, if any).
2109 *
2110 * This function will insert data into the blob, and will therefore
2111 * change the offsets of some existing nodes.
2112 *
2113 * returns:
2114 *	structure block offset of the created nodeequested subnode (>=0), on
2115 *		success
2116 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
2117 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
2118 *		tag
2119 *	-FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
2120 *		the given name
2121 *	-FDT_ERR_NOSPACE, if there is insufficient free space in the
2122 *		blob to contain the new node
2123 *	-FDT_ERR_NOSPACE
2124 *	-FDT_ERR_BADLAYOUT
2125 *      -FDT_ERR_BADMAGIC,
2126 *	-FDT_ERR_BADVERSION,
2127 *	-FDT_ERR_BADSTATE,
2128 *	-FDT_ERR_BADSTRUCTURE,
2129 *	-FDT_ERR_TRUNCATED, standard meanings.
2130 */
2131int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
2132
2133/**
2134 * fdt_del_node - delete a node (subtree)
2135 * @fdt: pointer to the device tree blob
2136 * @nodeoffset: offset of the node to nop
2137 *
2138 * fdt_del_node() will remove the given node, including all its
2139 * subnodes if any, from the blob.
2140 *
2141 * This function will delete data from the blob, and will therefore
2142 * change the offsets of some existing nodes.
2143 *
2144 * returns:
2145 *	0, on success
2146 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2147 *	-FDT_ERR_BADLAYOUT,
2148 *	-FDT_ERR_BADMAGIC,
2149 *	-FDT_ERR_BADVERSION,
2150 *	-FDT_ERR_BADSTATE,
2151 *	-FDT_ERR_BADSTRUCTURE,
2152 *	-FDT_ERR_TRUNCATED, standard meanings
2153 */
2154int fdt_del_node(void *fdt, int nodeoffset);
2155
2156/**
2157 * fdt_overlay_apply - Applies a DT overlay on a base DT
2158 * @fdt: pointer to the base device tree blob
2159 * @fdto: pointer to the device tree overlay blob
2160 *
2161 * fdt_overlay_apply() will apply the given device tree overlay on the
2162 * given base device tree.
2163 *
2164 * Expect the base device tree to be modified, even if the function
2165 * returns an error.
2166 *
2167 * returns:
2168 *	0, on success
2169 *	-FDT_ERR_NOSPACE, there's not enough space in the base device tree
2170 *	-FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
2171 *		properties in the base DT
2172 *	-FDT_ERR_BADPHANDLE,
2173 *	-FDT_ERR_BADOVERLAY,
2174 *	-FDT_ERR_NOPHANDLES,
2175 *	-FDT_ERR_INTERNAL,
2176 *	-FDT_ERR_BADLAYOUT,
2177 *	-FDT_ERR_BADMAGIC,
2178 *	-FDT_ERR_BADOFFSET,
2179 *	-FDT_ERR_BADPATH,
2180 *	-FDT_ERR_BADVERSION,
2181 *	-FDT_ERR_BADSTRUCTURE,
2182 *	-FDT_ERR_BADSTATE,
2183 *	-FDT_ERR_TRUNCATED, standard meanings
2184 */
2185int fdt_overlay_apply(void *fdt, void *fdto);
2186
2187/**
2188 * fdt_overlay_target_offset - retrieves the offset of a fragment's target
2189 * @fdt: Base device tree blob
2190 * @fdto: Device tree overlay blob
2191 * @fragment_offset: node offset of the fragment in the overlay
2192 * @pathp: pointer which receives the path of the target (or NULL)
2193 *
2194 * fdt_overlay_target_offset() retrieves the target offset in the base
2195 * device tree of a fragment, no matter how the actual targeting is
2196 * done (through a phandle or a path)
2197 *
2198 * returns:
2199 *      the targeted node offset in the base device tree
2200 *      Negative error code on error
2201 */
2202int fdt_overlay_target_offset(const void *fdt, const void *fdto,
2203			      int fragment_offset, char const **pathp);
2204
2205/**********************************************************************/
2206/* Debugging / informational functions                                */
2207/**********************************************************************/
2208
2209const char *fdt_strerror(int errval);
2210
2211#ifdef __cplusplus
2212}
2213#endif
2214
2215#endif /* LIBFDT_H */
v3.5.6
   1#ifndef _LIBFDT_H
   2#define _LIBFDT_H
 
   3/*
   4 * libfdt - Flat Device Tree manipulation
   5 * Copyright (C) 2006 David Gibson, IBM Corporation.
   6 *
   7 * libfdt is dual licensed: you can use it either under the terms of
   8 * the GPL, or the BSD license, at your option.
   9 *
  10 *  a) This library is free software; you can redistribute it and/or
  11 *     modify it under the terms of the GNU General Public License as
  12 *     published by the Free Software Foundation; either version 2 of the
  13 *     License, or (at your option) any later version.
  14 *
  15 *     This library is distributed in the hope that it will be useful,
  16 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 *     GNU General Public License for more details.
  19 *
  20 *     You should have received a copy of the GNU General Public
  21 *     License along with this library; if not, write to the Free
  22 *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  23 *     MA 02110-1301 USA
  24 *
  25 * Alternatively,
  26 *
  27 *  b) Redistribution and use in source and binary forms, with or
  28 *     without modification, are permitted provided that the following
  29 *     conditions are met:
  30 *
  31 *     1. Redistributions of source code must retain the above
  32 *        copyright notice, this list of conditions and the following
  33 *        disclaimer.
  34 *     2. Redistributions in binary form must reproduce the above
  35 *        copyright notice, this list of conditions and the following
  36 *        disclaimer in the documentation and/or other materials
  37 *        provided with the distribution.
  38 *
  39 *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  40 *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  41 *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  42 *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  43 *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  44 *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45 *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46 *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47 *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48 *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  49 *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  50 *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
  51 *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  52 */
  53
  54#include <libfdt_env.h>
  55#include <fdt.h>
 
 
 
 
  56
  57#define FDT_FIRST_SUPPORTED_VERSION	0x10
 
  58#define FDT_LAST_SUPPORTED_VERSION	0x11
  59
  60/* Error codes: informative error codes */
  61#define FDT_ERR_NOTFOUND	1
  62	/* FDT_ERR_NOTFOUND: The requested node or property does not exist */
  63#define FDT_ERR_EXISTS		2
  64	/* FDT_ERR_EXISTS: Attempted to create a node or property which
  65	 * already exists */
  66#define FDT_ERR_NOSPACE		3
  67	/* FDT_ERR_NOSPACE: Operation needed to expand the device
  68	 * tree, but its buffer did not have sufficient space to
  69	 * contain the expanded tree. Use fdt_open_into() to move the
  70	 * device tree to a buffer with more space. */
  71
  72/* Error codes: codes for bad parameters */
  73#define FDT_ERR_BADOFFSET	4
  74	/* FDT_ERR_BADOFFSET: Function was passed a structure block
  75	 * offset which is out-of-bounds, or which points to an
  76	 * unsuitable part of the structure for the operation. */
  77#define FDT_ERR_BADPATH		5
  78	/* FDT_ERR_BADPATH: Function was passed a badly formatted path
  79	 * (e.g. missing a leading / for a function which requires an
  80	 * absolute path) */
  81#define FDT_ERR_BADPHANDLE	6
  82	/* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle
  83	 * value.  phandle values of 0 and -1 are not permitted. */
 
 
  84#define FDT_ERR_BADSTATE	7
  85	/* FDT_ERR_BADSTATE: Function was passed an incomplete device
  86	 * tree created by the sequential-write functions, which is
  87	 * not sufficiently complete for the requested operation. */
  88
  89/* Error codes: codes for bad device tree blobs */
  90#define FDT_ERR_TRUNCATED	8
  91	/* FDT_ERR_TRUNCATED: Structure block of the given device tree
  92	 * ends without an FDT_END tag. */
 
  93#define FDT_ERR_BADMAGIC	9
  94	/* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
  95	 * device tree at all - it is missing the flattened device
  96	 * tree magic number. */
  97#define FDT_ERR_BADVERSION	10
  98	/* FDT_ERR_BADVERSION: Given device tree has a version which
  99	 * can't be handled by the requested operation.  For
 100	 * read-write functions, this may mean that fdt_open_into() is
 101	 * required to convert the tree to the expected version. */
 102#define FDT_ERR_BADSTRUCTURE	11
 103	/* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt
 104	 * structure block or other serious error (e.g. misnested
 105	 * nodes, or subnodes preceding properties). */
 106#define FDT_ERR_BADLAYOUT	12
 107	/* FDT_ERR_BADLAYOUT: For read-write functions, the given
 108	 * device tree has it's sub-blocks in an order that the
 109	 * function can't handle (memory reserve map, then structure,
 110	 * then strings).  Use fdt_open_into() to reorganize the tree
 111	 * into a form suitable for the read-write operations. */
 112
 113/* "Can't happen" error indicating a bug in libfdt */
 114#define FDT_ERR_INTERNAL	13
 115	/* FDT_ERR_INTERNAL: libfdt has failed an internal assertion.
 116	 * Should never be returned, if it is, it indicates a bug in
 117	 * libfdt itself. */
 118
 119#define FDT_ERR_MAX		13
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 120
 121/**********************************************************************/
 122/* Low-level functions (you probably don't need these)                */
 123/**********************************************************************/
 124
 125const void *fdt_offset_ptr(const void *fdt, int offset, int checklen);
 
 
 126static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
 127{
 128	return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
 129}
 130
 131uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
 132
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 133/**********************************************************************/
 134/* Traversal functions                                                */
 135/**********************************************************************/
 136
 137int fdt_next_node(const void *fdt, int offset, int *depth);
 138
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 139/**********************************************************************/
 140/* General functions                                                  */
 141/**********************************************************************/
 142
 143#define fdt_get_header(fdt, field) \
 144	(fdt32_to_cpu(((const struct fdt_header *)(fdt))->field))
 145#define fdt_magic(fdt) 			(fdt_get_header(fdt, magic))
 146#define fdt_totalsize(fdt)		(fdt_get_header(fdt, totalsize))
 147#define fdt_off_dt_struct(fdt)		(fdt_get_header(fdt, off_dt_struct))
 148#define fdt_off_dt_strings(fdt)		(fdt_get_header(fdt, off_dt_strings))
 149#define fdt_off_mem_rsvmap(fdt)		(fdt_get_header(fdt, off_mem_rsvmap))
 150#define fdt_version(fdt)		(fdt_get_header(fdt, version))
 151#define fdt_last_comp_version(fdt) 	(fdt_get_header(fdt, last_comp_version))
 152#define fdt_boot_cpuid_phys(fdt) 	(fdt_get_header(fdt, boot_cpuid_phys))
 153#define fdt_size_dt_strings(fdt) 	(fdt_get_header(fdt, size_dt_strings))
 154#define fdt_size_dt_struct(fdt)		(fdt_get_header(fdt, size_dt_struct))
 155
 156#define __fdt_set_hdr(name) \
 157	static inline void fdt_set_##name(void *fdt, uint32_t val) \
 158	{ \
 159		struct fdt_header *fdth = fdt; \
 160		fdth->name = cpu_to_fdt32(val); \
 161	}
 162__fdt_set_hdr(magic);
 163__fdt_set_hdr(totalsize);
 164__fdt_set_hdr(off_dt_struct);
 165__fdt_set_hdr(off_dt_strings);
 166__fdt_set_hdr(off_mem_rsvmap);
 167__fdt_set_hdr(version);
 168__fdt_set_hdr(last_comp_version);
 169__fdt_set_hdr(boot_cpuid_phys);
 170__fdt_set_hdr(size_dt_strings);
 171__fdt_set_hdr(size_dt_struct);
 172#undef __fdt_set_hdr
 173
 174/**
 175 * fdt_check_header - sanity check a device tree or possible device tree
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 176 * @fdt: pointer to data which might be a flattened device tree
 177 *
 178 * fdt_check_header() checks that the given buffer contains what
 179 * appears to be a flattened device tree with sane information in its
 180 * header.
 
 181 *
 182 * returns:
 183 *     0, if the buffer appears to contain a valid device tree
 184 *     -FDT_ERR_BADMAGIC,
 185 *     -FDT_ERR_BADVERSION,
 186 *     -FDT_ERR_BADSTATE, standard meanings, as above
 
 187 */
 188int fdt_check_header(const void *fdt);
 189
 190/**
 191 * fdt_move - move a device tree around in memory
 192 * @fdt: pointer to the device tree to move
 193 * @buf: pointer to memory where the device is to be moved
 194 * @bufsize: size of the memory space at buf
 195 *
 196 * fdt_move() relocates, if possible, the device tree blob located at
 197 * fdt to the buffer at buf of size bufsize.  The buffer may overlap
 198 * with the existing device tree blob at fdt.  Therefore,
 199 *     fdt_move(fdt, fdt, fdt_totalsize(fdt))
 200 * should always succeed.
 201 *
 202 * returns:
 203 *     0, on success
 204 *     -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
 205 *     -FDT_ERR_BADMAGIC,
 206 *     -FDT_ERR_BADVERSION,
 207 *     -FDT_ERR_BADSTATE, standard meanings
 208 */
 209int fdt_move(const void *fdt, void *buf, int bufsize);
 210
 211/**********************************************************************/
 212/* Read-only functions                                                */
 213/**********************************************************************/
 214
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 215/**
 216 * fdt_string - retrieve a string from the strings block of a device tree
 217 * @fdt: pointer to the device tree blob
 218 * @stroffset: offset of the string within the strings block (native endian)
 219 *
 220 * fdt_string() retrieves a pointer to a single string from the
 221 * strings block of the device tree blob at fdt.
 222 *
 223 * returns:
 224 *     a pointer to the string, on success
 225 *     NULL, if stroffset is out of bounds
 226 */
 227const char *fdt_string(const void *fdt, int stroffset);
 228
 229/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 230 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
 231 * @fdt: pointer to the device tree blob
 232 *
 233 * Returns the number of entries in the device tree blob's memory
 234 * reservation map.  This does not include the terminating 0,0 entry
 235 * or any other (0,0) entries reserved for expansion.
 236 *
 237 * returns:
 238 *     the number of entries
 239 */
 240int fdt_num_mem_rsv(const void *fdt);
 241
 242/**
 243 * fdt_get_mem_rsv - retrieve one memory reserve map entry
 244 * @fdt: pointer to the device tree blob
 245 * @address, @size: pointers to 64-bit variables
 
 
 246 *
 247 * On success, *address and *size will contain the address and size of
 248 * the n-th reserve map entry from the device tree blob, in
 249 * native-endian format.
 250 *
 251 * returns:
 252 *     0, on success
 253 *     -FDT_ERR_BADMAGIC,
 254 *     -FDT_ERR_BADVERSION,
 255 *     -FDT_ERR_BADSTATE, standard meanings
 256 */
 257int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
 258
 259/**
 260 * fdt_subnode_offset_namelen - find a subnode based on substring
 261 * @fdt: pointer to the device tree blob
 262 * @parentoffset: structure block offset of a node
 263 * @name: name of the subnode to locate
 264 * @namelen: number of characters of name to consider
 265 *
 266 * Identical to fdt_subnode_offset(), but only examine the first
 267 * namelen characters of name for matching the subnode name.  This is
 268 * useful for finding subnodes based on a portion of a larger string,
 269 * such as a full path.
 
 
 270 */
 
 271int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
 272			       const char *name, int namelen);
 
 273/**
 274 * fdt_subnode_offset - find a subnode of a given node
 275 * @fdt: pointer to the device tree blob
 276 * @parentoffset: structure block offset of a node
 277 * @name: name of the subnode to locate
 278 *
 279 * fdt_subnode_offset() finds a subnode of the node at structure block
 280 * offset parentoffset with the given name.  name may include a unit
 281 * address, in which case fdt_subnode_offset() will find the subnode
 282 * with that unit address, or the unit address may be omitted, in
 283 * which case fdt_subnode_offset() will find an arbitrary subnode
 284 * whose name excluding unit address matches the given name.
 285 *
 286 * returns:
 287 *	structure block offset of the requested subnode (>=0), on success
 288 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
 289 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
 290 *      -FDT_ERR_BADMAGIC,
 
 291 *	-FDT_ERR_BADVERSION,
 292 *	-FDT_ERR_BADSTATE,
 293 *	-FDT_ERR_BADSTRUCTURE,
 294 *	-FDT_ERR_TRUNCATED, standard meanings.
 295 */
 296int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
 297
 298/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 299 * fdt_path_offset - find a tree node by its full path
 300 * @fdt: pointer to the device tree blob
 301 * @path: full path of the node to locate
 302 *
 303 * fdt_path_offset() finds a node of a given path in the device tree.
 304 * Each path component may omit the unit address portion, but the
 305 * results of this are undefined if any such path component is
 306 * ambiguous (that is if there are multiple nodes at the relevant
 307 * level matching the given component, differentiated only by unit
 308 * address).
 309 *
 310 * returns:
 311 *	structure block offset of the node with the requested path (>=0), on success
 312 *	-FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 313 *	-FDT_ERR_NOTFOUND, if the requested node does not exist
 314 *      -FDT_ERR_BADMAGIC,
 315 *	-FDT_ERR_BADVERSION,
 316 *	-FDT_ERR_BADSTATE,
 317 *	-FDT_ERR_BADSTRUCTURE,
 318 *	-FDT_ERR_TRUNCATED, standard meanings.
 319 */
 320int fdt_path_offset(const void *fdt, const char *path);
 321
 322/**
 323 * fdt_get_name - retrieve the name of a given node
 324 * @fdt: pointer to the device tree blob
 325 * @nodeoffset: structure block offset of the starting node
 326 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 327 *
 328 * fdt_get_name() retrieves the name (including unit address) of the
 329 * device tree node at structure block offset nodeoffset.  If lenp is
 330 * non-NULL, the length of this name is also returned, in the integer
 331 * pointed to by lenp.
 332 *
 333 * returns:
 334 *	pointer to the node's name, on success
 335 *		If lenp is non-NULL, *lenp contains the length of that name (>=0)
 
 336 *	NULL, on error
 337 *		if lenp is non-NULL *lenp contains an error code (<0):
 338 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 
 339 *		-FDT_ERR_BADMAGIC,
 340 *		-FDT_ERR_BADVERSION,
 341 *		-FDT_ERR_BADSTATE, standard meanings
 342 */
 343const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
 344
 345/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 346 * fdt_get_property - find a given property in a given node
 347 * @fdt: pointer to the device tree blob
 348 * @nodeoffset: offset of the node whose property to find
 349 * @name: name of the property to find
 350 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 351 *
 352 * fdt_get_property() retrieves a pointer to the fdt_property
 353 * structure within the device tree blob corresponding to the property
 354 * named 'name' of the node at offset nodeoffset.  If lenp is
 355 * non-NULL, the length of the property value is also returned, in the
 356 * integer pointed to by lenp.
 357 *
 358 * returns:
 359 *	pointer to the structure representing the property
 360 *		if lenp is non-NULL, *lenp contains the length of the property
 361 *		value (>=0)
 362 *	NULL, on error
 363 *		if lenp is non-NULL, *lenp contains an error code (<0):
 364 *		-FDT_ERR_NOTFOUND, node does not have named property
 365 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 
 366 *		-FDT_ERR_BADMAGIC,
 367 *		-FDT_ERR_BADVERSION,
 368 *		-FDT_ERR_BADSTATE,
 369 *		-FDT_ERR_BADSTRUCTURE,
 370 *		-FDT_ERR_TRUNCATED, standard meanings
 371 */
 372const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
 373					    const char *name, int *lenp);
 374static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
 375						      const char *name,
 376						      int *lenp)
 377{
 378	return (struct fdt_property *)(uintptr_t)
 379		fdt_get_property(fdt, nodeoffset, name, lenp);
 380}
 381
 382/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 383 * fdt_getprop - retrieve the value of a given property
 384 * @fdt: pointer to the device tree blob
 385 * @nodeoffset: offset of the node whose property to find
 386 * @name: name of the property to find
 387 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 388 *
 389 * fdt_getprop() retrieves a pointer to the value of the property
 390 * named 'name' of the node at offset nodeoffset (this will be a
 391 * pointer to within the device blob itself, not a copy of the value).
 392 * If lenp is non-NULL, the length of the property value is also
 393 * returned, in the integer pointed to by lenp.
 394 *
 395 * returns:
 396 *	pointer to the property's value
 397 *		if lenp is non-NULL, *lenp contains the length of the property
 398 *		value (>=0)
 399 *	NULL, on error
 400 *		if lenp is non-NULL, *lenp contains an error code (<0):
 401 *		-FDT_ERR_NOTFOUND, node does not have named property
 402 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 
 403 *		-FDT_ERR_BADMAGIC,
 404 *		-FDT_ERR_BADVERSION,
 405 *		-FDT_ERR_BADSTATE,
 406 *		-FDT_ERR_BADSTRUCTURE,
 407 *		-FDT_ERR_TRUNCATED, standard meanings
 408 */
 409const void *fdt_getprop(const void *fdt, int nodeoffset,
 410			const char *name, int *lenp);
 411static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
 412				  const char *name, int *lenp)
 413{
 414	return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
 415}
 416
 417/**
 418 * fdt_get_phandle - retrieve the phandle of a given node
 419 * @fdt: pointer to the device tree blob
 420 * @nodeoffset: structure block offset of the node
 421 *
 422 * fdt_get_phandle() retrieves the phandle of the device tree node at
 423 * structure block offset nodeoffset.
 424 *
 425 * returns:
 426 *	the phandle of the node at nodeoffset, on success (!= 0, != -1)
 427 *	0, if the node has no phandle, or another error occurs
 428 */
 429uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
 430
 431/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 432 * fdt_get_path - determine the full path of a node
 433 * @fdt: pointer to the device tree blob
 434 * @nodeoffset: offset of the node whose path to find
 435 * @buf: character buffer to contain the returned path (will be overwritten)
 436 * @buflen: size of the character buffer at buf
 437 *
 438 * fdt_get_path() computes the full path of the node at offset
 439 * nodeoffset, and records that path in the buffer at buf.
 440 *
 441 * NOTE: This function is expensive, as it must scan the device tree
 442 * structure from the start to nodeoffset.
 443 *
 444 * returns:
 445 *	0, on success
 446 *		buf contains the absolute path of the node at
 447 *		nodeoffset, as a NUL-terminated string.
 448 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 449 *	-FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
 450 *		characters and will not fit in the given buffer.
 451 *	-FDT_ERR_BADMAGIC,
 452 *	-FDT_ERR_BADVERSION,
 453 *	-FDT_ERR_BADSTATE,
 454 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 455 */
 456int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
 457
 458/**
 459 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
 460 * @fdt: pointer to the device tree blob
 461 * @nodeoffset: offset of the node whose parent to find
 462 * @supernodedepth: depth of the ancestor to find
 463 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
 464 *
 465 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
 466 * at a specific depth from the root (where the root itself has depth
 467 * 0, its immediate subnodes depth 1 and so forth).  So
 468 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
 469 * will always return 0, the offset of the root node.  If the node at
 470 * nodeoffset has depth D, then:
 471 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
 472 * will return nodeoffset itself.
 473 *
 474 * NOTE: This function is expensive, as it must scan the device tree
 475 * structure from the start to nodeoffset.
 476 *
 477 * returns:
 478
 479 *	structure block offset of the node at node offset's ancestor
 480 *		of depth supernodedepth (>=0), on success
 481 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 482*	-FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of nodeoffset
 
 483 *	-FDT_ERR_BADMAGIC,
 484 *	-FDT_ERR_BADVERSION,
 485 *	-FDT_ERR_BADSTATE,
 486 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 487 */
 488int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
 489				 int supernodedepth, int *nodedepth);
 490
 491/**
 492 * fdt_node_depth - find the depth of a given node
 493 * @fdt: pointer to the device tree blob
 494 * @nodeoffset: offset of the node whose parent to find
 495 *
 496 * fdt_node_depth() finds the depth of a given node.  The root node
 497 * has depth 0, its immediate subnodes depth 1 and so forth.
 498 *
 499 * NOTE: This function is expensive, as it must scan the device tree
 500 * structure from the start to nodeoffset.
 501 *
 502 * returns:
 503 *	depth of the node at nodeoffset (>=0), on success
 504 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 505 *	-FDT_ERR_BADMAGIC,
 506 *	-FDT_ERR_BADVERSION,
 507 *	-FDT_ERR_BADSTATE,
 508 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 509 */
 510int fdt_node_depth(const void *fdt, int nodeoffset);
 511
 512/**
 513 * fdt_parent_offset - find the parent of a given node
 514 * @fdt: pointer to the device tree blob
 515 * @nodeoffset: offset of the node whose parent to find
 516 *
 517 * fdt_parent_offset() locates the parent node of a given node (that
 518 * is, it finds the offset of the node which contains the node at
 519 * nodeoffset as a subnode).
 520 *
 521 * NOTE: This function is expensive, as it must scan the device tree
 522 * structure from the start to nodeoffset, *twice*.
 523 *
 524 * returns:
 525 *	structure block offset of the parent of the node at nodeoffset
 526 *		(>=0), on success
 527 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 528 *	-FDT_ERR_BADMAGIC,
 529 *	-FDT_ERR_BADVERSION,
 530 *	-FDT_ERR_BADSTATE,
 531 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 532 */
 533int fdt_parent_offset(const void *fdt, int nodeoffset);
 534
 535/**
 536 * fdt_node_offset_by_prop_value - find nodes with a given property value
 537 * @fdt: pointer to the device tree blob
 538 * @startoffset: only find nodes after this offset
 539 * @propname: property name to check
 540 * @propval: property value to search for
 541 * @proplen: length of the value in propval
 542 *
 543 * fdt_node_offset_by_prop_value() returns the offset of the first
 544 * node after startoffset, which has a property named propname whose
 545 * value is of length proplen and has value equal to propval; or if
 546 * startoffset is -1, the very first such node in the tree.
 547 *
 548 * To iterate through all nodes matching the criterion, the following
 549 * idiom can be used:
 550 *	offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
 551 *					       propval, proplen);
 552 *	while (offset != -FDT_ERR_NOTFOUND) {
 553 *		// other code here
 554 *		offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
 555 *						       propval, proplen);
 556 *	}
 557 *
 558 * Note the -1 in the first call to the function, if 0 is used here
 559 * instead, the function will never locate the root node, even if it
 560 * matches the criterion.
 561 *
 562 * returns:
 563 *	structure block offset of the located node (>= 0, >startoffset),
 564 *		 on success
 565 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
 566 *		tree after startoffset
 567 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 568 *	-FDT_ERR_BADMAGIC,
 569 *	-FDT_ERR_BADVERSION,
 570 *	-FDT_ERR_BADSTATE,
 571 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 572 */
 573int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
 574				  const char *propname,
 575				  const void *propval, int proplen);
 576
 577/**
 578 * fdt_node_offset_by_phandle - find the node with a given phandle
 579 * @fdt: pointer to the device tree blob
 580 * @phandle: phandle value
 581 *
 582 * fdt_node_offset_by_phandle() returns the offset of the node
 583 * which has the given phandle value.  If there is more than one node
 584 * in the tree with the given phandle (an invalid tree), results are
 585 * undefined.
 586 *
 587 * returns:
 588 *	structure block offset of the located node (>= 0), on success
 589 *	-FDT_ERR_NOTFOUND, no node with that phandle exists
 590 *	-FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
 591 *	-FDT_ERR_BADMAGIC,
 592 *	-FDT_ERR_BADVERSION,
 593 *	-FDT_ERR_BADSTATE,
 594 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 595 */
 596int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
 597
 598/**
 599 * fdt_node_check_compatible: check a node's compatible property
 600 * @fdt: pointer to the device tree blob
 601 * @nodeoffset: offset of a tree node
 602 * @compatible: string to match against
 603 *
 604 *
 605 * fdt_node_check_compatible() returns 0 if the given node contains a
 606 * 'compatible' property with the given string as one of its elements,
 607 * it returns non-zero otherwise, or on error.
 608 *
 609 * returns:
 610 *	0, if the node has a 'compatible' property listing the given string
 611 *	1, if the node has a 'compatible' property, but it does not list
 612 *		the given string
 613 *	-FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
 614 * 	-FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
 615 *	-FDT_ERR_BADMAGIC,
 616 *	-FDT_ERR_BADVERSION,
 617 *	-FDT_ERR_BADSTATE,
 618 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 619 */
 620int fdt_node_check_compatible(const void *fdt, int nodeoffset,
 621			      const char *compatible);
 622
 623/**
 624 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
 625 * @fdt: pointer to the device tree blob
 626 * @startoffset: only find nodes after this offset
 627 * @compatible: 'compatible' string to match against
 628 *
 629 * fdt_node_offset_by_compatible() returns the offset of the first
 630 * node after startoffset, which has a 'compatible' property which
 631 * lists the given compatible string; or if startoffset is -1, the
 632 * very first such node in the tree.
 633 *
 634 * To iterate through all nodes matching the criterion, the following
 635 * idiom can be used:
 636 *	offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
 637 *	while (offset != -FDT_ERR_NOTFOUND) {
 638 *		// other code here
 639 *		offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
 640 *	}
 641 *
 642 * Note the -1 in the first call to the function, if 0 is used here
 643 * instead, the function will never locate the root node, even if it
 644 * matches the criterion.
 645 *
 646 * returns:
 647 *	structure block offset of the located node (>= 0, >startoffset),
 648 *		 on success
 649 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
 650 *		tree after startoffset
 651 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 652 *	-FDT_ERR_BADMAGIC,
 653 *	-FDT_ERR_BADVERSION,
 654 *	-FDT_ERR_BADSTATE,
 655 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 656 */
 657int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
 658				  const char *compatible);
 659
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 660/**********************************************************************/
 661/* Write-in-place functions                                           */
 662/**********************************************************************/
 663
 664/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 665 * fdt_setprop_inplace - change a property's value, but not its size
 666 * @fdt: pointer to the device tree blob
 667 * @nodeoffset: offset of the node whose property to change
 668 * @name: name of the property to change
 669 * @val: pointer to data to replace the property value with
 670 * @len: length of the property value
 671 *
 672 * fdt_setprop_inplace() replaces the value of a given property with
 673 * the data in val, of length len.  This function cannot change the
 674 * size of a property, and so will only work if len is equal to the
 675 * current length of the property.
 676 *
 677 * This function will alter only the bytes in the blob which contain
 678 * the given property value, and will not alter or move any other part
 679 * of the tree.
 680 *
 681 * returns:
 682 *	0, on success
 683 *	-FDT_ERR_NOSPACE, if len is not equal to the property's current length
 684 *	-FDT_ERR_NOTFOUND, node does not have the named property
 685 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 686 *	-FDT_ERR_BADMAGIC,
 687 *	-FDT_ERR_BADVERSION,
 688 *	-FDT_ERR_BADSTATE,
 689 *	-FDT_ERR_BADSTRUCTURE,
 690 *	-FDT_ERR_TRUNCATED, standard meanings
 691 */
 
 692int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
 693			const void *val, int len);
 
 694
 695/**
 696 * fdt_setprop_inplace_cell - change the value of a single-cell property
 697 * @fdt: pointer to the device tree blob
 698 * @nodeoffset: offset of the node whose property to change
 699 * @name: name of the property to change
 700 * @val: cell (32-bit integer) value to replace the property with
 701 *
 702 * fdt_setprop_inplace_cell() replaces the value of a given property
 703 * with the 32-bit integer cell value in val, converting val to
 704 * big-endian if necessary.  This function cannot change the size of a
 705 * property, and so will only work if the property already exists and
 706 * has length 4.
 707 *
 708 * This function will alter only the bytes in the blob which contain
 709 * the given property value, and will not alter or move any other part
 710 * of the tree.
 711 *
 712 * returns:
 713 *	0, on success
 714 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 4
 715  *	-FDT_ERR_NOTFOUND, node does not have the named property
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 716 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 717 *	-FDT_ERR_BADMAGIC,
 718 *	-FDT_ERR_BADVERSION,
 719 *	-FDT_ERR_BADSTATE,
 720 *	-FDT_ERR_BADSTRUCTURE,
 721 *	-FDT_ERR_TRUNCATED, standard meanings
 722 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 723static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
 724					   const char *name, uint32_t val)
 725{
 726	val = cpu_to_fdt32(val);
 727	return fdt_setprop_inplace(fdt, nodeoffset, name, &val, sizeof(val));
 728}
 729
 730/**
 731 * fdt_nop_property - replace a property with nop tags
 732 * @fdt: pointer to the device tree blob
 733 * @nodeoffset: offset of the node whose property to nop
 734 * @name: name of the property to nop
 735 *
 736 * fdt_nop_property() will replace a given property's representation
 737 * in the blob with FDT_NOP tags, effectively removing it from the
 738 * tree.
 739 *
 740 * This function will alter only the bytes in the blob which contain
 741 * the property, and will not alter or move any other part of the
 742 * tree.
 743 *
 744 * returns:
 745 *	0, on success
 746 *	-FDT_ERR_NOTFOUND, node does not have the named property
 747 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 748 *	-FDT_ERR_BADMAGIC,
 749 *	-FDT_ERR_BADVERSION,
 750 *	-FDT_ERR_BADSTATE,
 751 *	-FDT_ERR_BADSTRUCTURE,
 752 *	-FDT_ERR_TRUNCATED, standard meanings
 753 */
 754int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
 755
 756/**
 757 * fdt_nop_node - replace a node (subtree) with nop tags
 758 * @fdt: pointer to the device tree blob
 759 * @nodeoffset: offset of the node to nop
 760 *
 761 * fdt_nop_node() will replace a given node's representation in the
 762 * blob, including all its subnodes, if any, with FDT_NOP tags,
 763 * effectively removing it from the tree.
 764 *
 765 * This function will alter only the bytes in the blob which contain
 766 * the node and its properties and subnodes, and will not alter or
 767 * move any other part of the tree.
 768 *
 769 * returns:
 770 *	0, on success
 771 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 772 *	-FDT_ERR_BADMAGIC,
 773 *	-FDT_ERR_BADVERSION,
 774 *	-FDT_ERR_BADSTATE,
 775 *	-FDT_ERR_BADSTRUCTURE,
 776 *	-FDT_ERR_TRUNCATED, standard meanings
 777 */
 778int fdt_nop_node(void *fdt, int nodeoffset);
 779
 780/**********************************************************************/
 781/* Sequential write functions                                         */
 782/**********************************************************************/
 783
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 784int fdt_create(void *buf, int bufsize);
 
 
 785int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
 786int fdt_finish_reservemap(void *fdt);
 787int fdt_begin_node(void *fdt, const char *name);
 788int fdt_property(void *fdt, const char *name, const void *val, int len);
 
 
 
 
 
 
 
 
 
 
 
 
 789static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
 790{
 791	val = cpu_to_fdt32(val);
 792	return fdt_property(fdt, name, &val, sizeof(val));
 793}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 794#define fdt_property_string(fdt, name, str) \
 795	fdt_property(fdt, name, str, strlen(str)+1)
 796int fdt_end_node(void *fdt);
 797int fdt_finish(void *fdt);
 798
 799/**********************************************************************/
 800/* Read-write functions                                               */
 801/**********************************************************************/
 802
 
 803int fdt_open_into(const void *fdt, void *buf, int bufsize);
 804int fdt_pack(void *fdt);
 805
 806/**
 807 * fdt_add_mem_rsv - add one memory reserve map entry
 808 * @fdt: pointer to the device tree blob
 809 * @address, @size: 64-bit values (native endian)
 
 810 *
 811 * Adds a reserve map entry to the given blob reserving a region at
 812 * address address of length size.
 813 *
 814 * This function will insert data into the reserve map and will
 815 * therefore change the indexes of some entries in the table.
 816 *
 817 * returns:
 818 *	0, on success
 819 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 820 *		contain the new reservation entry
 821 *	-FDT_ERR_BADMAGIC,
 822 *	-FDT_ERR_BADVERSION,
 823 *	-FDT_ERR_BADSTATE,
 824 *	-FDT_ERR_BADSTRUCTURE,
 825 *	-FDT_ERR_BADLAYOUT,
 826 *	-FDT_ERR_TRUNCATED, standard meanings
 827 */
 828int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
 829
 830/**
 831 * fdt_del_mem_rsv - remove a memory reserve map entry
 832 * @fdt: pointer to the device tree blob
 833 * @n: entry to remove
 834 *
 835 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
 836 * the blob.
 837 *
 838 * This function will delete data from the reservation table and will
 839 * therefore change the indexes of some entries in the table.
 840 *
 841 * returns:
 842 *	0, on success
 843 *	-FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
 844 *		are less than n+1 reserve map entries)
 845 *	-FDT_ERR_BADMAGIC,
 846 *	-FDT_ERR_BADVERSION,
 847 *	-FDT_ERR_BADSTATE,
 848 *	-FDT_ERR_BADSTRUCTURE,
 849 *	-FDT_ERR_BADLAYOUT,
 850 *	-FDT_ERR_TRUNCATED, standard meanings
 851 */
 852int fdt_del_mem_rsv(void *fdt, int n);
 853
 854/**
 855 * fdt_set_name - change the name of a given node
 856 * @fdt: pointer to the device tree blob
 857 * @nodeoffset: structure block offset of a node
 858 * @name: name to give the node
 859 *
 860 * fdt_set_name() replaces the name (including unit address, if any)
 861 * of the given node with the given string.  NOTE: this function can't
 862 * efficiently check if the new name is unique amongst the given
 863 * node's siblings; results are undefined if this function is invoked
 864 * with a name equal to one of the given node's siblings.
 865 *
 866 * This function may insert or delete data from the blob, and will
 867 * therefore change the offsets of some existing nodes.
 868 *
 869 * returns:
 870 *	0, on success
 871 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob
 872 *		to contain the new name
 873 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 874 *	-FDT_ERR_BADMAGIC,
 875 *	-FDT_ERR_BADVERSION,
 876 *	-FDT_ERR_BADSTATE, standard meanings
 877 */
 878int fdt_set_name(void *fdt, int nodeoffset, const char *name);
 879
 880/**
 881 * fdt_setprop - create or change a property
 882 * @fdt: pointer to the device tree blob
 883 * @nodeoffset: offset of the node whose property to change
 884 * @name: name of the property to change
 885 * @val: pointer to data to set the property value to
 886 * @len: length of the property value
 887 *
 888 * fdt_setprop() sets the value of the named property in the given
 889 * node to the given value and length, creating the property if it
 890 * does not already exist.
 891 *
 892 * This function may insert or delete data from the blob, and will
 893 * therefore change the offsets of some existing nodes.
 894 *
 895 * returns:
 896 *	0, on success
 897 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 898 *		contain the new property value
 899 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 900 *	-FDT_ERR_BADLAYOUT,
 901 *	-FDT_ERR_BADMAGIC,
 902 *	-FDT_ERR_BADVERSION,
 903 *	-FDT_ERR_BADSTATE,
 904 *	-FDT_ERR_BADSTRUCTURE,
 905 *	-FDT_ERR_BADLAYOUT,
 906 *	-FDT_ERR_TRUNCATED, standard meanings
 907 */
 908int fdt_setprop(void *fdt, int nodeoffset, const char *name,
 909		const void *val, int len);
 910
 911/**
 912 * fdt_setprop_cell - set a property to a single cell value
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 913 * @fdt: pointer to the device tree blob
 914 * @nodeoffset: offset of the node whose property to change
 915 * @name: name of the property to change
 916 * @val: 32-bit integer value for the property (native endian)
 917 *
 918 * fdt_setprop_cell() sets the value of the named property in the
 919 * given node to the given cell value (converting to big-endian if
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 920 * necessary), or creates a new property with that value if it does
 921 * not already exist.
 922 *
 923 * This function may insert or delete data from the blob, and will
 924 * therefore change the offsets of some existing nodes.
 925 *
 926 * returns:
 927 *	0, on success
 928 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 929 *		contain the new property value
 930 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 931 *	-FDT_ERR_BADLAYOUT,
 932 *	-FDT_ERR_BADMAGIC,
 933 *	-FDT_ERR_BADVERSION,
 934 *	-FDT_ERR_BADSTATE,
 935 *	-FDT_ERR_BADSTRUCTURE,
 936 *	-FDT_ERR_BADLAYOUT,
 937 *	-FDT_ERR_TRUNCATED, standard meanings
 938 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 939static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
 940				   uint32_t val)
 941{
 942	val = cpu_to_fdt32(val);
 943	return fdt_setprop(fdt, nodeoffset, name, &val, sizeof(val));
 944}
 945
 946/**
 947 * fdt_setprop_string - set a property to a string value
 948 * @fdt: pointer to the device tree blob
 949 * @nodeoffset: offset of the node whose property to change
 950 * @name: name of the property to change
 951 * @str: string value for the property
 952 *
 953 * fdt_setprop_string() sets the value of the named property in the
 954 * given node to the given string value (using the length of the
 955 * string to determine the new length of the property), or creates a
 956 * new property with that value if it does not already exist.
 957 *
 958 * This function may insert or delete data from the blob, and will
 959 * therefore change the offsets of some existing nodes.
 960 *
 961 * returns:
 962 *	0, on success
 963 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 964 *		contain the new property value
 965 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 966 *	-FDT_ERR_BADLAYOUT,
 967 *	-FDT_ERR_BADMAGIC,
 968 *	-FDT_ERR_BADVERSION,
 969 *	-FDT_ERR_BADSTATE,
 970 *	-FDT_ERR_BADSTRUCTURE,
 971 *	-FDT_ERR_BADLAYOUT,
 972 *	-FDT_ERR_TRUNCATED, standard meanings
 973 */
 974#define fdt_setprop_string(fdt, nodeoffset, name, str) \
 975	fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
 976
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 977/**
 978 * fdt_delprop - delete a property
 979 * @fdt: pointer to the device tree blob
 980 * @nodeoffset: offset of the node whose property to nop
 981 * @name: name of the property to nop
 982 *
 983 * fdt_del_property() will delete the given property.
 984 *
 985 * This function will delete data from the blob, and will therefore
 986 * change the offsets of some existing nodes.
 987 *
 988 * returns:
 989 *	0, on success
 990 *	-FDT_ERR_NOTFOUND, node does not have the named property
 991 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 992 *	-FDT_ERR_BADLAYOUT,
 993 *	-FDT_ERR_BADMAGIC,
 994 *	-FDT_ERR_BADVERSION,
 995 *	-FDT_ERR_BADSTATE,
 996 *	-FDT_ERR_BADSTRUCTURE,
 997 *	-FDT_ERR_TRUNCATED, standard meanings
 998 */
 999int fdt_delprop(void *fdt, int nodeoffset, const char *name);
1000
1001/**
1002 * fdt_add_subnode_namelen - creates a new node based on substring
1003 * @fdt: pointer to the device tree blob
1004 * @parentoffset: structure block offset of a node
1005 * @name: name of the subnode to locate
1006 * @namelen: number of characters of name to consider
1007 *
1008 * Identical to fdt_add_subnode(), but use only the first namelen
1009 * characters of name as the name of the new node.  This is useful for
1010 * creating subnodes based on a portion of a larger string, such as a
1011 * full path.
 
 
 
1012 */
 
1013int fdt_add_subnode_namelen(void *fdt, int parentoffset,
1014			    const char *name, int namelen);
 
1015
1016/**
1017 * fdt_add_subnode - creates a new node
1018 * @fdt: pointer to the device tree blob
1019 * @parentoffset: structure block offset of a node
1020 * @name: name of the subnode to locate
1021 *
1022 * fdt_add_subnode() creates a new node as a subnode of the node at
1023 * structure block offset parentoffset, with the given name (which
1024 * should include the unit address, if any).
1025 *
1026 * This function will insert data into the blob, and will therefore
1027 * change the offsets of some existing nodes.
1028
1029 * returns:
1030 *	structure block offset of the created nodeequested subnode (>=0), on success
 
1031 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
1032 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
 
1033 *	-FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
1034 *		the given name
1035 *	-FDT_ERR_NOSPACE, if there is insufficient free space in the
1036 *		blob to contain the new node
1037 *	-FDT_ERR_NOSPACE
1038 *	-FDT_ERR_BADLAYOUT
1039 *      -FDT_ERR_BADMAGIC,
1040 *	-FDT_ERR_BADVERSION,
1041 *	-FDT_ERR_BADSTATE,
1042 *	-FDT_ERR_BADSTRUCTURE,
1043 *	-FDT_ERR_TRUNCATED, standard meanings.
1044 */
1045int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
1046
1047/**
1048 * fdt_del_node - delete a node (subtree)
1049 * @fdt: pointer to the device tree blob
1050 * @nodeoffset: offset of the node to nop
1051 *
1052 * fdt_del_node() will remove the given node, including all its
1053 * subnodes if any, from the blob.
1054 *
1055 * This function will delete data from the blob, and will therefore
1056 * change the offsets of some existing nodes.
1057 *
1058 * returns:
1059 *	0, on success
1060 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1061 *	-FDT_ERR_BADLAYOUT,
1062 *	-FDT_ERR_BADMAGIC,
1063 *	-FDT_ERR_BADVERSION,
1064 *	-FDT_ERR_BADSTATE,
1065 *	-FDT_ERR_BADSTRUCTURE,
1066 *	-FDT_ERR_TRUNCATED, standard meanings
1067 */
1068int fdt_del_node(void *fdt, int nodeoffset);
1069
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1070/**********************************************************************/
1071/* Debugging / informational functions                                */
1072/**********************************************************************/
1073
1074const char *fdt_strerror(int errval);
1075
1076#endif /* _LIBFDT_H */