Linux Audio

Check our new training course

Loading...
v6.13.7
   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 */
v5.9
   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_SUPPORTED_VERSION	0x11
  18
  19/* Error codes: informative error codes */
  20#define FDT_ERR_NOTFOUND	1
  21	/* FDT_ERR_NOTFOUND: The requested node or property does not exist */
  22#define FDT_ERR_EXISTS		2
  23	/* FDT_ERR_EXISTS: Attempted to create a node or property which
  24	 * already exists */
  25#define FDT_ERR_NOSPACE		3
  26	/* FDT_ERR_NOSPACE: Operation needed to expand the device
  27	 * tree, but its buffer did not have sufficient space to
  28	 * contain the expanded tree. Use fdt_open_into() to move the
  29	 * device tree to a buffer with more space. */
  30
  31/* Error codes: codes for bad parameters */
  32#define FDT_ERR_BADOFFSET	4
  33	/* FDT_ERR_BADOFFSET: Function was passed a structure block
  34	 * offset which is out-of-bounds, or which points to an
  35	 * unsuitable part of the structure for the operation. */
  36#define FDT_ERR_BADPATH		5
  37	/* FDT_ERR_BADPATH: Function was passed a badly formatted path
  38	 * (e.g. missing a leading / for a function which requires an
  39	 * absolute path) */
  40#define FDT_ERR_BADPHANDLE	6
  41	/* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle.
  42	 * This can be caused either by an invalid phandle property
  43	 * length, or the phandle value was either 0 or -1, which are
  44	 * not permitted. */
  45#define FDT_ERR_BADSTATE	7
  46	/* FDT_ERR_BADSTATE: Function was passed an incomplete device
  47	 * tree created by the sequential-write functions, which is
  48	 * not sufficiently complete for the requested operation. */
  49
  50/* Error codes: codes for bad device tree blobs */
  51#define FDT_ERR_TRUNCATED	8
  52	/* FDT_ERR_TRUNCATED: FDT or a sub-block is improperly
  53	 * terminated (overflows, goes outside allowed bounds, or
  54	 * isn't properly terminated).  */
  55#define FDT_ERR_BADMAGIC	9
  56	/* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
  57	 * device tree at all - it is missing the flattened device
  58	 * tree magic number. */
  59#define FDT_ERR_BADVERSION	10
  60	/* FDT_ERR_BADVERSION: Given device tree has a version which
  61	 * can't be handled by the requested operation.  For
  62	 * read-write functions, this may mean that fdt_open_into() is
  63	 * required to convert the tree to the expected version. */
  64#define FDT_ERR_BADSTRUCTURE	11
  65	/* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt
  66	 * structure block or other serious error (e.g. misnested
  67	 * nodes, or subnodes preceding properties). */
  68#define FDT_ERR_BADLAYOUT	12
  69	/* FDT_ERR_BADLAYOUT: For read-write functions, the given
  70	 * device tree has it's sub-blocks in an order that the
  71	 * function can't handle (memory reserve map, then structure,
  72	 * then strings).  Use fdt_open_into() to reorganize the tree
  73	 * into a form suitable for the read-write operations. */
  74
  75/* "Can't happen" error indicating a bug in libfdt */
  76#define FDT_ERR_INTERNAL	13
  77	/* FDT_ERR_INTERNAL: libfdt has failed an internal assertion.
  78	 * Should never be returned, if it is, it indicates a bug in
  79	 * libfdt itself. */
  80
  81/* Errors in device tree content */
  82#define FDT_ERR_BADNCELLS	14
  83	/* FDT_ERR_BADNCELLS: Device tree has a #address-cells, #size-cells
  84	 * or similar property with a bad format or value */
  85
  86#define FDT_ERR_BADVALUE	15
  87	/* FDT_ERR_BADVALUE: Device tree has a property with an unexpected
  88	 * value. For example: a property expected to contain a string list
  89	 * is not NUL-terminated within the length of its value. */
  90
  91#define FDT_ERR_BADOVERLAY	16
  92	/* FDT_ERR_BADOVERLAY: The device tree overlay, while
  93	 * correctly structured, cannot be applied due to some
  94	 * unexpected or missing value, property or node. */
  95
  96#define FDT_ERR_NOPHANDLES	17
  97	/* FDT_ERR_NOPHANDLES: The device tree doesn't have any
  98	 * phandle available anymore without causing an overflow */
  99
 100#define FDT_ERR_BADFLAGS	18
 101	/* FDT_ERR_BADFLAGS: The function was passed a flags field that
 102	 * contains invalid flags or an invalid combination of flags. */
 103
 104#define FDT_ERR_MAX		18
 
 
 
 
 105
 106/* constants */
 107#define FDT_MAX_PHANDLE 0xfffffffe
 108	/* Valid values for phandles range from 1 to 2^32-2. */
 109
 110/**********************************************************************/
 111/* Low-level functions (you probably don't need these)                */
 112/**********************************************************************/
 113
 114#ifndef SWIG /* This function is not useful in Python */
 115const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen);
 116#endif
 117static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
 118{
 119	return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
 120}
 121
 122uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
 123
 124/*
 125 * Alignment helpers:
 126 *     These helpers access words from a device tree blob.  They're
 127 *     built to work even with unaligned pointers on platforms (ike
 128 *     ARM) that don't like unaligned loads and stores
 129 */
 
 
 
 
 
 
 130
 131static inline uint32_t fdt32_ld(const fdt32_t *p)
 132{
 133	const uint8_t *bp = (const uint8_t *)p;
 134
 135	return ((uint32_t)bp[0] << 24)
 136		| ((uint32_t)bp[1] << 16)
 137		| ((uint32_t)bp[2] << 8)
 138		| bp[3];
 139}
 140
 141static inline void fdt32_st(void *property, uint32_t value)
 142{
 143	uint8_t *bp = (uint8_t *)property;
 144
 145	bp[0] = value >> 24;
 146	bp[1] = (value >> 16) & 0xff;
 147	bp[2] = (value >> 8) & 0xff;
 148	bp[3] = value & 0xff;
 149}
 150
 151static inline uint64_t fdt64_ld(const fdt64_t *p)
 152{
 153	const uint8_t *bp = (const uint8_t *)p;
 154
 155	return ((uint64_t)bp[0] << 56)
 156		| ((uint64_t)bp[1] << 48)
 157		| ((uint64_t)bp[2] << 40)
 158		| ((uint64_t)bp[3] << 32)
 159		| ((uint64_t)bp[4] << 24)
 160		| ((uint64_t)bp[5] << 16)
 161		| ((uint64_t)bp[6] << 8)
 162		| bp[7];
 163}
 164
 165static inline void fdt64_st(void *property, uint64_t value)
 166{
 167	uint8_t *bp = (uint8_t *)property;
 168
 169	bp[0] = value >> 56;
 170	bp[1] = (value >> 48) & 0xff;
 171	bp[2] = (value >> 40) & 0xff;
 172	bp[3] = (value >> 32) & 0xff;
 173	bp[4] = (value >> 24) & 0xff;
 174	bp[5] = (value >> 16) & 0xff;
 175	bp[6] = (value >> 8) & 0xff;
 176	bp[7] = value & 0xff;
 177}
 178
 179/**********************************************************************/
 180/* Traversal functions                                                */
 181/**********************************************************************/
 182
 183int fdt_next_node(const void *fdt, int offset, int *depth);
 184
 185/**
 186 * fdt_first_subnode() - get offset of first direct subnode
 187 *
 188 * @fdt:	FDT blob
 189 * @offset:	Offset of node to check
 190 * @return offset of first subnode, or -FDT_ERR_NOTFOUND if there is none
 
 191 */
 192int fdt_first_subnode(const void *fdt, int offset);
 193
 194/**
 195 * fdt_next_subnode() - get offset of next direct subnode
 
 
 196 *
 197 * After first calling fdt_first_subnode(), call this function repeatedly to
 198 * get direct subnodes of a parent node.
 199 *
 200 * @fdt:	FDT blob
 201 * @offset:	Offset of previous subnode
 202 * @return offset of next subnode, or -FDT_ERR_NOTFOUND if there are no more
 203 * subnodes
 204 */
 205int fdt_next_subnode(const void *fdt, int offset);
 206
 207/**
 208 * fdt_for_each_subnode - iterate over all subnodes of a parent
 209 *
 210 * @node:	child node (int, lvalue)
 211 * @fdt:	FDT blob (const void *)
 212 * @parent:	parent node (int)
 213 *
 214 * This is actually a wrapper around a for loop and would be used like so:
 215 *
 216 *	fdt_for_each_subnode(node, fdt, parent) {
 217 *		Use node
 218 *		...
 219 *	}
 220 *
 221 *	if ((node < 0) && (node != -FDT_ERR_NOTFOUND)) {
 222 *		Error handling
 223 *	}
 224 *
 225 * Note that this is implemented as a macro and @node is used as
 226 * iterator in the loop. The parent variable be constant or even a
 227 * literal.
 228 *
 229 */
 230#define fdt_for_each_subnode(node, fdt, parent)		\
 231	for (node = fdt_first_subnode(fdt, parent);	\
 232	     node >= 0;					\
 233	     node = fdt_next_subnode(fdt, node))
 234
 235/**********************************************************************/
 236/* General functions                                                  */
 237/**********************************************************************/
 238#define fdt_get_header(fdt, field) \
 239	(fdt32_ld(&((const struct fdt_header *)(fdt))->field))
 240#define fdt_magic(fdt)			(fdt_get_header(fdt, magic))
 241#define fdt_totalsize(fdt)		(fdt_get_header(fdt, totalsize))
 242#define fdt_off_dt_struct(fdt)		(fdt_get_header(fdt, off_dt_struct))
 243#define fdt_off_dt_strings(fdt)		(fdt_get_header(fdt, off_dt_strings))
 244#define fdt_off_mem_rsvmap(fdt)		(fdt_get_header(fdt, off_mem_rsvmap))
 245#define fdt_version(fdt)		(fdt_get_header(fdt, version))
 246#define fdt_last_comp_version(fdt)	(fdt_get_header(fdt, last_comp_version))
 247#define fdt_boot_cpuid_phys(fdt)	(fdt_get_header(fdt, boot_cpuid_phys))
 248#define fdt_size_dt_strings(fdt)	(fdt_get_header(fdt, size_dt_strings))
 249#define fdt_size_dt_struct(fdt)		(fdt_get_header(fdt, size_dt_struct))
 250
 251#define fdt_set_hdr_(name) \
 252	static inline void fdt_set_##name(void *fdt, uint32_t val) \
 253	{ \
 254		struct fdt_header *fdth = (struct fdt_header *)fdt; \
 255		fdth->name = cpu_to_fdt32(val); \
 256	}
 257fdt_set_hdr_(magic);
 258fdt_set_hdr_(totalsize);
 259fdt_set_hdr_(off_dt_struct);
 260fdt_set_hdr_(off_dt_strings);
 261fdt_set_hdr_(off_mem_rsvmap);
 262fdt_set_hdr_(version);
 263fdt_set_hdr_(last_comp_version);
 264fdt_set_hdr_(boot_cpuid_phys);
 265fdt_set_hdr_(size_dt_strings);
 266fdt_set_hdr_(size_dt_struct);
 267#undef fdt_set_hdr_
 268
 269/**
 270 * fdt_header_size - return the size of the tree's header
 271 * @fdt: pointer to a flattened device tree
 
 
 272 */
 273size_t fdt_header_size(const void *fdt);
 274
 275/**
 276 * fdt_header_size_ - internal function which takes a version number
 
 
 
 277 */
 278size_t fdt_header_size_(uint32_t version);
 279
 280/**
 281 * fdt_check_header - sanity check a device tree header
 282
 283 * @fdt: pointer to data which might be a flattened device tree
 284 *
 285 * fdt_check_header() checks that the given buffer contains what
 286 * appears to be a flattened device tree, and that the header contains
 287 * valid information (to the extent that can be determined from the
 288 * header alone).
 289 *
 290 * returns:
 291 *     0, if the buffer appears to contain a valid device tree
 292 *     -FDT_ERR_BADMAGIC,
 293 *     -FDT_ERR_BADVERSION,
 294 *     -FDT_ERR_BADSTATE,
 295 *     -FDT_ERR_TRUNCATED, standard meanings, as above
 296 */
 297int fdt_check_header(const void *fdt);
 298
 299/**
 300 * fdt_move - move a device tree around in memory
 301 * @fdt: pointer to the device tree to move
 302 * @buf: pointer to memory where the device is to be moved
 303 * @bufsize: size of the memory space at buf
 304 *
 305 * fdt_move() relocates, if possible, the device tree blob located at
 306 * fdt to the buffer at buf of size bufsize.  The buffer may overlap
 307 * with the existing device tree blob at fdt.  Therefore,
 308 *     fdt_move(fdt, fdt, fdt_totalsize(fdt))
 309 * should always succeed.
 310 *
 311 * returns:
 312 *     0, on success
 313 *     -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
 314 *     -FDT_ERR_BADMAGIC,
 315 *     -FDT_ERR_BADVERSION,
 316 *     -FDT_ERR_BADSTATE, standard meanings
 317 */
 318int fdt_move(const void *fdt, void *buf, int bufsize);
 319
 320/**********************************************************************/
 321/* Read-only functions                                                */
 322/**********************************************************************/
 323
 324int fdt_check_full(const void *fdt, size_t bufsize);
 325
 326/**
 327 * fdt_get_string - retrieve a string from the strings block of a device tree
 328 * @fdt: pointer to the device tree blob
 329 * @stroffset: offset of the string within the strings block (native endian)
 330 * @lenp: optional pointer to return the string's length
 331 *
 332 * fdt_get_string() retrieves a pointer to a single string from the
 333 * strings block of the device tree blob at fdt, and optionally also
 334 * returns the string's length in *lenp.
 335 *
 336 * returns:
 337 *     a pointer to the string, on success
 338 *     NULL, if stroffset is out of bounds, or doesn't point to a valid string
 339 */
 340const char *fdt_get_string(const void *fdt, int stroffset, int *lenp);
 341
 342/**
 343 * fdt_string - retrieve a string from the strings block of a device tree
 344 * @fdt: pointer to the device tree blob
 345 * @stroffset: offset of the string within the strings block (native endian)
 346 *
 347 * fdt_string() retrieves a pointer to a single string from the
 348 * strings block of the device tree blob at fdt.
 349 *
 350 * returns:
 351 *     a pointer to the string, on success
 352 *     NULL, if stroffset is out of bounds, or doesn't point to a valid string
 353 */
 354const char *fdt_string(const void *fdt, int stroffset);
 355
 356/**
 357 * fdt_find_max_phandle - find and return the highest phandle in a tree
 358 * @fdt: pointer to the device tree blob
 359 * @phandle: return location for the highest phandle value found in the tree
 360 *
 361 * fdt_find_max_phandle() finds the highest phandle value in the given device
 362 * tree. The value returned in @phandle is only valid if the function returns
 363 * success.
 364 *
 365 * returns:
 366 *     0 on success or a negative error code on failure
 367 */
 368int fdt_find_max_phandle(const void *fdt, uint32_t *phandle);
 369
 370/**
 371 * fdt_get_max_phandle - retrieves the highest phandle in a tree
 372 * @fdt: pointer to the device tree blob
 373 *
 374 * fdt_get_max_phandle retrieves the highest phandle in the given
 375 * device tree. This will ignore badly formatted phandles, or phandles
 376 * with a value of 0 or -1.
 377 *
 378 * This function is deprecated in favour of fdt_find_max_phandle().
 379 *
 380 * returns:
 381 *      the highest phandle on success
 382 *      0, if no phandle was found in the device tree
 383 *      -1, if an error occurred
 384 */
 385static inline uint32_t fdt_get_max_phandle(const void *fdt)
 386{
 387	uint32_t phandle;
 388	int err;
 389
 390	err = fdt_find_max_phandle(fdt, &phandle);
 391	if (err < 0)
 392		return (uint32_t)-1;
 393
 394	return phandle;
 395}
 396
 397/**
 398 * fdt_generate_phandle - return a new, unused phandle for a device tree blob
 399 * @fdt: pointer to the device tree blob
 400 * @phandle: return location for the new phandle
 401 *
 402 * Walks the device tree blob and looks for the highest phandle value. On
 403 * success, the new, unused phandle value (one higher than the previously
 404 * highest phandle value in the device tree blob) will be returned in the
 405 * @phandle parameter.
 406 *
 407 * Returns:
 408 *   0 on success or a negative error-code on failure
 409 */
 410int fdt_generate_phandle(const void *fdt, uint32_t *phandle);
 411
 412/**
 413 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
 414 * @fdt: pointer to the device tree blob
 415 *
 416 * Returns the number of entries in the device tree blob's memory
 417 * reservation map.  This does not include the terminating 0,0 entry
 418 * or any other (0,0) entries reserved for expansion.
 419 *
 420 * returns:
 421 *     the number of entries
 422 */
 423int fdt_num_mem_rsv(const void *fdt);
 424
 425/**
 426 * fdt_get_mem_rsv - retrieve one memory reserve map entry
 427 * @fdt: pointer to the device tree blob
 428 * @address, @size: pointers to 64-bit variables
 
 
 429 *
 430 * On success, *address and *size will contain the address and size of
 431 * the n-th reserve map entry from the device tree blob, in
 432 * native-endian format.
 433 *
 434 * returns:
 435 *     0, on success
 436 *     -FDT_ERR_BADMAGIC,
 437 *     -FDT_ERR_BADVERSION,
 438 *     -FDT_ERR_BADSTATE, standard meanings
 439 */
 440int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
 441
 442/**
 443 * fdt_subnode_offset_namelen - find a subnode based on substring
 444 * @fdt: pointer to the device tree blob
 445 * @parentoffset: structure block offset of a node
 446 * @name: name of the subnode to locate
 447 * @namelen: number of characters of name to consider
 448 *
 449 * Identical to fdt_subnode_offset(), but only examine the first
 450 * namelen characters of name for matching the subnode name.  This is
 451 * useful for finding subnodes based on a portion of a larger string,
 452 * such as a full path.
 
 
 453 */
 454#ifndef SWIG /* Not available in Python */
 455int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
 456			       const char *name, int namelen);
 457#endif
 458/**
 459 * fdt_subnode_offset - find a subnode of a given node
 460 * @fdt: pointer to the device tree blob
 461 * @parentoffset: structure block offset of a node
 462 * @name: name of the subnode to locate
 463 *
 464 * fdt_subnode_offset() finds a subnode of the node at structure block
 465 * offset parentoffset with the given name.  name may include a unit
 466 * address, in which case fdt_subnode_offset() will find the subnode
 467 * with that unit address, or the unit address may be omitted, in
 468 * which case fdt_subnode_offset() will find an arbitrary subnode
 469 * whose name excluding unit address matches the given name.
 470 *
 471 * returns:
 472 *	structure block offset of the requested subnode (>=0), on success
 473 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
 474 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
 475 *		tag
 476 *	-FDT_ERR_BADMAGIC,
 477 *	-FDT_ERR_BADVERSION,
 478 *	-FDT_ERR_BADSTATE,
 479 *	-FDT_ERR_BADSTRUCTURE,
 480 *	-FDT_ERR_TRUNCATED, standard meanings.
 481 */
 482int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
 483
 484/**
 485 * fdt_path_offset_namelen - find a tree node by its full path
 486 * @fdt: pointer to the device tree blob
 487 * @path: full path of the node to locate
 488 * @namelen: number of characters of path to consider
 489 *
 490 * Identical to fdt_path_offset(), but only consider the first namelen
 491 * characters of path as the path name.
 
 
 492 */
 493#ifndef SWIG /* Not available in Python */
 494int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen);
 495#endif
 496
 497/**
 498 * fdt_path_offset - find a tree node by its full path
 499 * @fdt: pointer to the device tree blob
 500 * @path: full path of the node to locate
 501 *
 502 * fdt_path_offset() finds a node of a given path in the device tree.
 503 * Each path component may omit the unit address portion, but the
 504 * results of this are undefined if any such path component is
 505 * ambiguous (that is if there are multiple nodes at the relevant
 506 * level matching the given component, differentiated only by unit
 507 * address).
 508 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 509 * returns:
 510 *	structure block offset of the node with the requested path (>=0), on
 511 *		success
 512 *	-FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
 
 513 *	-FDT_ERR_NOTFOUND, if the requested node does not exist
 514 *      -FDT_ERR_BADMAGIC,
 515 *	-FDT_ERR_BADVERSION,
 516 *	-FDT_ERR_BADSTATE,
 517 *	-FDT_ERR_BADSTRUCTURE,
 518 *	-FDT_ERR_TRUNCATED, standard meanings.
 519 */
 520int fdt_path_offset(const void *fdt, const char *path);
 521
 522/**
 523 * fdt_get_name - retrieve the name of a given node
 524 * @fdt: pointer to the device tree blob
 525 * @nodeoffset: structure block offset of the starting node
 526 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 527 *
 528 * fdt_get_name() retrieves the name (including unit address) of the
 529 * device tree node at structure block offset nodeoffset.  If lenp is
 530 * non-NULL, the length of this name is also returned, in the integer
 531 * pointed to by lenp.
 532 *
 533 * returns:
 534 *	pointer to the node's name, on success
 535 *		If lenp is non-NULL, *lenp contains the length of that name
 536 *			(>=0)
 537 *	NULL, on error
 538 *		if lenp is non-NULL *lenp contains an error code (<0):
 539 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
 540 *			tag
 541 *		-FDT_ERR_BADMAGIC,
 542 *		-FDT_ERR_BADVERSION,
 543 *		-FDT_ERR_BADSTATE, standard meanings
 544 */
 545const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
 546
 547/**
 548 * fdt_first_property_offset - find the offset of a node's first property
 549 * @fdt: pointer to the device tree blob
 550 * @nodeoffset: structure block offset of a node
 551 *
 552 * fdt_first_property_offset() finds the first property of the node at
 553 * the given structure block offset.
 554 *
 555 * returns:
 556 *	structure block offset of the property (>=0), on success
 557 *	-FDT_ERR_NOTFOUND, if the requested node has no properties
 558 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
 559 *      -FDT_ERR_BADMAGIC,
 560 *	-FDT_ERR_BADVERSION,
 561 *	-FDT_ERR_BADSTATE,
 562 *	-FDT_ERR_BADSTRUCTURE,
 563 *	-FDT_ERR_TRUNCATED, standard meanings.
 564 */
 565int fdt_first_property_offset(const void *fdt, int nodeoffset);
 566
 567/**
 568 * fdt_next_property_offset - step through a node's properties
 569 * @fdt: pointer to the device tree blob
 570 * @offset: structure block offset of a property
 571 *
 572 * fdt_next_property_offset() finds the property immediately after the
 573 * one at the given structure block offset.  This will be a property
 574 * of the same node as the given property.
 575 *
 576 * returns:
 577 *	structure block offset of the next property (>=0), on success
 578 *	-FDT_ERR_NOTFOUND, if the given property is the last in its node
 579 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag
 580 *      -FDT_ERR_BADMAGIC,
 581 *	-FDT_ERR_BADVERSION,
 582 *	-FDT_ERR_BADSTATE,
 583 *	-FDT_ERR_BADSTRUCTURE,
 584 *	-FDT_ERR_TRUNCATED, standard meanings.
 585 */
 586int fdt_next_property_offset(const void *fdt, int offset);
 587
 588/**
 589 * fdt_for_each_property_offset - iterate over all properties of a node
 590 *
 591 * @property_offset:	property offset (int, lvalue)
 592 * @fdt:		FDT blob (const void *)
 593 * @node:		node offset (int)
 594 *
 595 * This is actually a wrapper around a for loop and would be used like so:
 596 *
 597 *	fdt_for_each_property_offset(property, fdt, node) {
 598 *		Use property
 599 *		...
 600 *	}
 601 *
 602 *	if ((property < 0) && (property != -FDT_ERR_NOTFOUND)) {
 603 *		Error handling
 604 *	}
 605 *
 606 * Note that this is implemented as a macro and property is used as
 607 * iterator in the loop. The node variable can be constant or even a
 608 * literal.
 609 */
 610#define fdt_for_each_property_offset(property, fdt, node)	\
 611	for (property = fdt_first_property_offset(fdt, node);	\
 612	     property >= 0;					\
 613	     property = fdt_next_property_offset(fdt, property))
 614
 615/**
 616 * fdt_get_property_by_offset - retrieve the property at a given offset
 617 * @fdt: pointer to the device tree blob
 618 * @offset: offset of the property to retrieve
 619 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 620 *
 621 * fdt_get_property_by_offset() retrieves a pointer to the
 622 * fdt_property structure within the device tree blob at the given
 623 * offset.  If lenp is non-NULL, the length of the property value is
 624 * also returned, in the integer pointed to by lenp.
 625 *
 626 * Note that this code only works on device tree versions >= 16. fdt_getprop()
 627 * works on all versions.
 628 *
 629 * returns:
 630 *	pointer to the structure representing the property
 631 *		if lenp is non-NULL, *lenp contains the length of the property
 632 *		value (>=0)
 633 *	NULL, on error
 634 *		if lenp is non-NULL, *lenp contains an error code (<0):
 635 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
 636 *		-FDT_ERR_BADMAGIC,
 637 *		-FDT_ERR_BADVERSION,
 638 *		-FDT_ERR_BADSTATE,
 639 *		-FDT_ERR_BADSTRUCTURE,
 640 *		-FDT_ERR_TRUNCATED, standard meanings
 641 */
 642const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
 643						      int offset,
 644						      int *lenp);
 
 
 
 
 
 
 
 645
 646/**
 647 * fdt_get_property_namelen - find a property based on substring
 648 * @fdt: pointer to the device tree blob
 649 * @nodeoffset: offset of the node whose property to find
 650 * @name: name of the property to find
 651 * @namelen: number of characters of name to consider
 652 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 653 *
 654 * Identical to fdt_get_property(), but only examine the first namelen
 655 * characters of name for matching the property name.
 
 
 
 656 */
 657#ifndef SWIG /* Not available in Python */
 658const struct fdt_property *fdt_get_property_namelen(const void *fdt,
 659						    int nodeoffset,
 660						    const char *name,
 661						    int namelen, int *lenp);
 662#endif
 663
 664/**
 665 * fdt_get_property - find a given property in a given node
 666 * @fdt: pointer to the device tree blob
 667 * @nodeoffset: offset of the node whose property to find
 668 * @name: name of the property to find
 669 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 670 *
 671 * fdt_get_property() retrieves a pointer to the fdt_property
 672 * structure within the device tree blob corresponding to the property
 673 * named 'name' of the node at offset nodeoffset.  If lenp is
 674 * non-NULL, the length of the property value is also returned, in the
 675 * integer pointed to by lenp.
 676 *
 677 * returns:
 678 *	pointer to the structure representing the property
 679 *		if lenp is non-NULL, *lenp contains the length of the property
 680 *		value (>=0)
 681 *	NULL, on error
 682 *		if lenp is non-NULL, *lenp contains an error code (<0):
 683 *		-FDT_ERR_NOTFOUND, node does not have named property
 684 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
 685 *			tag
 686 *		-FDT_ERR_BADMAGIC,
 687 *		-FDT_ERR_BADVERSION,
 688 *		-FDT_ERR_BADSTATE,
 689 *		-FDT_ERR_BADSTRUCTURE,
 690 *		-FDT_ERR_TRUNCATED, standard meanings
 691 */
 692const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
 693					    const char *name, int *lenp);
 694static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
 695						      const char *name,
 696						      int *lenp)
 697{
 698	return (struct fdt_property *)(uintptr_t)
 699		fdt_get_property(fdt, nodeoffset, name, lenp);
 700}
 701
 702/**
 703 * fdt_getprop_by_offset - retrieve the value of a property at a given offset
 704 * @fdt: pointer to the device tree blob
 705 * @offset: offset of the property to read
 706 * @namep: pointer to a string variable (will be overwritten) or NULL
 707 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 708 *
 709 * fdt_getprop_by_offset() retrieves a pointer to the value of the
 710 * property at structure block offset 'offset' (this will be a pointer
 711 * to within the device blob itself, not a copy of the value).  If
 712 * lenp is non-NULL, the length of the property value is also
 713 * returned, in the integer pointed to by lenp.  If namep is non-NULL,
 714 * the property's namne will also be returned in the char * pointed to
 715 * by namep (this will be a pointer to within the device tree's string
 716 * block, not a new copy of the name).
 717 *
 718 * returns:
 719 *	pointer to the property's value
 720 *		if lenp is non-NULL, *lenp contains the length of the property
 721 *		value (>=0)
 722 *		if namep is non-NULL *namep contiains a pointer to the property
 723 *		name.
 724 *	NULL, on error
 725 *		if lenp is non-NULL, *lenp contains an error code (<0):
 726 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
 727 *		-FDT_ERR_BADMAGIC,
 728 *		-FDT_ERR_BADVERSION,
 729 *		-FDT_ERR_BADSTATE,
 730 *		-FDT_ERR_BADSTRUCTURE,
 731 *		-FDT_ERR_TRUNCATED, standard meanings
 732 */
 733#ifndef SWIG /* This function is not useful in Python */
 734const void *fdt_getprop_by_offset(const void *fdt, int offset,
 735				  const char **namep, int *lenp);
 736#endif
 737
 738/**
 739 * fdt_getprop_namelen - get property value based on substring
 740 * @fdt: pointer to the device tree blob
 741 * @nodeoffset: offset of the node whose property to find
 742 * @name: name of the property to find
 743 * @namelen: number of characters of name to consider
 744 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 745 *
 746 * Identical to fdt_getprop(), but only examine the first namelen
 747 * characters of name for matching the property name.
 
 
 748 */
 749#ifndef SWIG /* Not available in Python */
 750const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
 751				const char *name, int namelen, int *lenp);
 752static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset,
 753					  const char *name, int namelen,
 754					  int *lenp)
 755{
 756	return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name,
 757						      namelen, lenp);
 758}
 759#endif
 760
 761/**
 762 * fdt_getprop - retrieve the value of a given property
 763 * @fdt: pointer to the device tree blob
 764 * @nodeoffset: offset of the node whose property to find
 765 * @name: name of the property to find
 766 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 767 *
 768 * fdt_getprop() retrieves a pointer to the value of the property
 769 * named 'name' of the node at offset nodeoffset (this will be a
 770 * pointer to within the device blob itself, not a copy of the value).
 771 * If lenp is non-NULL, the length of the property value is also
 772 * returned, in the integer pointed to by lenp.
 773 *
 774 * returns:
 775 *	pointer to the property's value
 776 *		if lenp is non-NULL, *lenp contains the length of the property
 777 *		value (>=0)
 778 *	NULL, on error
 779 *		if lenp is non-NULL, *lenp contains an error code (<0):
 780 *		-FDT_ERR_NOTFOUND, node does not have named property
 781 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
 782 *			tag
 783 *		-FDT_ERR_BADMAGIC,
 784 *		-FDT_ERR_BADVERSION,
 785 *		-FDT_ERR_BADSTATE,
 786 *		-FDT_ERR_BADSTRUCTURE,
 787 *		-FDT_ERR_TRUNCATED, standard meanings
 788 */
 789const void *fdt_getprop(const void *fdt, int nodeoffset,
 790			const char *name, int *lenp);
 791static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
 792				  const char *name, int *lenp)
 793{
 794	return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
 795}
 796
 797/**
 798 * fdt_get_phandle - retrieve the phandle of a given node
 799 * @fdt: pointer to the device tree blob
 800 * @nodeoffset: structure block offset of the node
 801 *
 802 * fdt_get_phandle() retrieves the phandle of the device tree node at
 803 * structure block offset nodeoffset.
 804 *
 805 * returns:
 806 *	the phandle of the node at nodeoffset, on success (!= 0, != -1)
 807 *	0, if the node has no phandle, or another error occurs
 808 */
 809uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
 810
 811/**
 812 * fdt_get_alias_namelen - get alias based on substring
 813 * @fdt: pointer to the device tree blob
 814 * @name: name of the alias th look up
 815 * @namelen: number of characters of name to consider
 816 *
 817 * Identical to fdt_get_alias(), but only examine the first namelen
 818 * characters of name for matching the alias name.
 
 
 
 819 */
 820#ifndef SWIG /* Not available in Python */
 821const char *fdt_get_alias_namelen(const void *fdt,
 822				  const char *name, int namelen);
 823#endif
 824
 825/**
 826 * fdt_get_alias - retrieve the path referenced by a given alias
 827 * @fdt: pointer to the device tree blob
 828 * @name: name of the alias th look up
 829 *
 830 * fdt_get_alias() retrieves the value of a given alias.  That is, the
 831 * value of the property named 'name' in the node /aliases.
 832 *
 833 * returns:
 834 *	a pointer to the expansion of the alias named 'name', if it exists
 835 *	NULL, if the given alias or the /aliases node does not exist
 836 */
 837const char *fdt_get_alias(const void *fdt, const char *name);
 838
 839/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 840 * fdt_get_path - determine the full path of a node
 841 * @fdt: pointer to the device tree blob
 842 * @nodeoffset: offset of the node whose path to find
 843 * @buf: character buffer to contain the returned path (will be overwritten)
 844 * @buflen: size of the character buffer at buf
 845 *
 846 * fdt_get_path() computes the full path of the node at offset
 847 * nodeoffset, and records that path in the buffer at buf.
 848 *
 849 * NOTE: This function is expensive, as it must scan the device tree
 850 * structure from the start to nodeoffset.
 851 *
 852 * returns:
 853 *	0, on success
 854 *		buf contains the absolute path of the node at
 855 *		nodeoffset, as a NUL-terminated string.
 856 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 857 *	-FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
 858 *		characters and will not fit in the given buffer.
 859 *	-FDT_ERR_BADMAGIC,
 860 *	-FDT_ERR_BADVERSION,
 861 *	-FDT_ERR_BADSTATE,
 862 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 863 */
 864int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
 865
 866/**
 867 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
 868 * @fdt: pointer to the device tree blob
 869 * @nodeoffset: offset of the node whose parent to find
 870 * @supernodedepth: depth of the ancestor to find
 871 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
 872 *
 873 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
 874 * at a specific depth from the root (where the root itself has depth
 875 * 0, its immediate subnodes depth 1 and so forth).  So
 876 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
 877 * will always return 0, the offset of the root node.  If the node at
 878 * nodeoffset has depth D, then:
 879 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
 880 * will return nodeoffset itself.
 881 *
 882 * NOTE: This function is expensive, as it must scan the device tree
 883 * structure from the start to nodeoffset.
 884 *
 885 * returns:
 886 *	structure block offset of the node at node offset's ancestor
 887 *		of depth supernodedepth (>=0), on success
 888 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 889 *	-FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of
 890 *		nodeoffset
 891 *	-FDT_ERR_BADMAGIC,
 892 *	-FDT_ERR_BADVERSION,
 893 *	-FDT_ERR_BADSTATE,
 894 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 895 */
 896int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
 897				 int supernodedepth, int *nodedepth);
 898
 899/**
 900 * fdt_node_depth - find the depth of a given node
 901 * @fdt: pointer to the device tree blob
 902 * @nodeoffset: offset of the node whose parent to find
 903 *
 904 * fdt_node_depth() finds the depth of a given node.  The root node
 905 * has depth 0, its immediate subnodes depth 1 and so forth.
 906 *
 907 * NOTE: This function is expensive, as it must scan the device tree
 908 * structure from the start to nodeoffset.
 909 *
 910 * returns:
 911 *	depth of the node at nodeoffset (>=0), on success
 912 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 913 *	-FDT_ERR_BADMAGIC,
 914 *	-FDT_ERR_BADVERSION,
 915 *	-FDT_ERR_BADSTATE,
 916 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 917 */
 918int fdt_node_depth(const void *fdt, int nodeoffset);
 919
 920/**
 921 * fdt_parent_offset - find the parent of a given node
 922 * @fdt: pointer to the device tree blob
 923 * @nodeoffset: offset of the node whose parent to find
 924 *
 925 * fdt_parent_offset() locates the parent node of a given node (that
 926 * is, it finds the offset of the node which contains the node at
 927 * nodeoffset as a subnode).
 928 *
 929 * NOTE: This function is expensive, as it must scan the device tree
 930 * structure from the start to nodeoffset, *twice*.
 931 *
 932 * returns:
 933 *	structure block offset of the parent of the node at nodeoffset
 934 *		(>=0), on success
 935 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 936 *	-FDT_ERR_BADMAGIC,
 937 *	-FDT_ERR_BADVERSION,
 938 *	-FDT_ERR_BADSTATE,
 939 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 940 */
 941int fdt_parent_offset(const void *fdt, int nodeoffset);
 942
 943/**
 944 * fdt_node_offset_by_prop_value - find nodes with a given property value
 945 * @fdt: pointer to the device tree blob
 946 * @startoffset: only find nodes after this offset
 947 * @propname: property name to check
 948 * @propval: property value to search for
 949 * @proplen: length of the value in propval
 950 *
 951 * fdt_node_offset_by_prop_value() returns the offset of the first
 952 * node after startoffset, which has a property named propname whose
 953 * value is of length proplen and has value equal to propval; or if
 954 * startoffset is -1, the very first such node in the tree.
 955 *
 956 * To iterate through all nodes matching the criterion, the following
 957 * idiom can be used:
 958 *	offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
 959 *					       propval, proplen);
 960 *	while (offset != -FDT_ERR_NOTFOUND) {
 961 *		// other code here
 962 *		offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
 963 *						       propval, proplen);
 964 *	}
 965 *
 966 * Note the -1 in the first call to the function, if 0 is used here
 967 * instead, the function will never locate the root node, even if it
 968 * matches the criterion.
 969 *
 970 * returns:
 971 *	structure block offset of the located node (>= 0, >startoffset),
 972 *		 on success
 973 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
 974 *		tree after startoffset
 975 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 976 *	-FDT_ERR_BADMAGIC,
 977 *	-FDT_ERR_BADVERSION,
 978 *	-FDT_ERR_BADSTATE,
 979 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 980 */
 981int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
 982				  const char *propname,
 983				  const void *propval, int proplen);
 984
 985/**
 986 * fdt_node_offset_by_phandle - find the node with a given phandle
 987 * @fdt: pointer to the device tree blob
 988 * @phandle: phandle value
 989 *
 990 * fdt_node_offset_by_phandle() returns the offset of the node
 991 * which has the given phandle value.  If there is more than one node
 992 * in the tree with the given phandle (an invalid tree), results are
 993 * undefined.
 994 *
 995 * returns:
 996 *	structure block offset of the located node (>= 0), on success
 997 *	-FDT_ERR_NOTFOUND, no node with that phandle exists
 998 *	-FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
 999 *	-FDT_ERR_BADMAGIC,
1000 *	-FDT_ERR_BADVERSION,
1001 *	-FDT_ERR_BADSTATE,
1002 *	-FDT_ERR_BADSTRUCTURE, standard meanings
1003 */
1004int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
1005
1006/**
1007 * fdt_node_check_compatible: check a node's compatible property
1008 * @fdt: pointer to the device tree blob
1009 * @nodeoffset: offset of a tree node
1010 * @compatible: string to match against
1011 *
1012 *
1013 * fdt_node_check_compatible() returns 0 if the given node contains a
1014 * 'compatible' property with the given string as one of its elements,
1015 * it returns non-zero otherwise, or on error.
1016 *
1017 * returns:
1018 *	0, if the node has a 'compatible' property listing the given string
1019 *	1, if the node has a 'compatible' property, but it does not list
1020 *		the given string
1021 *	-FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
1022 *	-FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
1023 *	-FDT_ERR_BADMAGIC,
1024 *	-FDT_ERR_BADVERSION,
1025 *	-FDT_ERR_BADSTATE,
1026 *	-FDT_ERR_BADSTRUCTURE, standard meanings
1027 */
1028int fdt_node_check_compatible(const void *fdt, int nodeoffset,
1029			      const char *compatible);
1030
1031/**
1032 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
1033 * @fdt: pointer to the device tree blob
1034 * @startoffset: only find nodes after this offset
1035 * @compatible: 'compatible' string to match against
1036 *
1037 * fdt_node_offset_by_compatible() returns the offset of the first
1038 * node after startoffset, which has a 'compatible' property which
1039 * lists the given compatible string; or if startoffset is -1, the
1040 * very first such node in the tree.
1041 *
1042 * To iterate through all nodes matching the criterion, the following
1043 * idiom can be used:
1044 *	offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
1045 *	while (offset != -FDT_ERR_NOTFOUND) {
1046 *		// other code here
1047 *		offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
1048 *	}
1049 *
1050 * Note the -1 in the first call to the function, if 0 is used here
1051 * instead, the function will never locate the root node, even if it
1052 * matches the criterion.
1053 *
1054 * returns:
1055 *	structure block offset of the located node (>= 0, >startoffset),
1056 *		 on success
1057 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
1058 *		tree after startoffset
1059 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1060 *	-FDT_ERR_BADMAGIC,
1061 *	-FDT_ERR_BADVERSION,
1062 *	-FDT_ERR_BADSTATE,
1063 *	-FDT_ERR_BADSTRUCTURE, standard meanings
1064 */
1065int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
1066				  const char *compatible);
1067
1068/**
1069 * fdt_stringlist_contains - check a string list property for a string
1070 * @strlist: Property containing a list of strings to check
1071 * @listlen: Length of property
1072 * @str: String to search for
1073 *
1074 * This is a utility function provided for convenience. The list contains
1075 * one or more strings, each terminated by \0, as is found in a device tree
1076 * "compatible" property.
1077 *
1078 * @return: 1 if the string is found in the list, 0 not found, or invalid list
1079 */
1080int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
1081
1082/**
1083 * fdt_stringlist_count - count the number of strings in a string list
1084 * @fdt: pointer to the device tree blob
1085 * @nodeoffset: offset of a tree node
1086 * @property: name of the property containing the string list
1087 * @return:
 
1088 *   the number of strings in the given property
1089 *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1090 *   -FDT_ERR_NOTFOUND if the property does not exist
1091 */
1092int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property);
1093
1094/**
1095 * fdt_stringlist_search - find a string in a string list and return its index
1096 * @fdt: pointer to the device tree blob
1097 * @nodeoffset: offset of a tree node
1098 * @property: name of the property containing the string list
1099 * @string: string to look up in the string list
1100 *
1101 * Note that it is possible for this function to succeed on property values
1102 * that are not NUL-terminated. That's because the function will stop after
1103 * finding the first occurrence of @string. This can for example happen with
1104 * small-valued cell properties, such as #address-cells, when searching for
1105 * the empty string.
1106 *
1107 * @return:
1108 *   the index of the string in the list of strings
1109 *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1110 *   -FDT_ERR_NOTFOUND if the property does not exist or does not contain
1111 *                     the given string
1112 */
1113int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
1114			  const char *string);
1115
1116/**
1117 * fdt_stringlist_get() - obtain the string at a given index in a string list
1118 * @fdt: pointer to the device tree blob
1119 * @nodeoffset: offset of a tree node
1120 * @property: name of the property containing the string list
1121 * @index: index of the string to return
1122 * @lenp: return location for the string length or an error code on failure
1123 *
1124 * Note that this will successfully extract strings from properties with
1125 * non-NUL-terminated values. For example on small-valued cell properties
1126 * this function will return the empty string.
1127 *
1128 * If non-NULL, the length of the string (on success) or a negative error-code
1129 * (on failure) will be stored in the integer pointer to by lenp.
1130 *
1131 * @return:
1132 *   A pointer to the string at the given index in the string list or NULL on
1133 *   failure. On success the length of the string will be stored in the memory
1134 *   location pointed to by the lenp parameter, if non-NULL. On failure one of
1135 *   the following negative error codes will be returned in the lenp parameter
1136 *   (if non-NULL):
1137 *     -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1138 *     -FDT_ERR_NOTFOUND if the property does not exist
1139 */
1140const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
1141			       const char *property, int index,
1142			       int *lenp);
1143
1144/**********************************************************************/
1145/* Read-only functions (addressing related)                           */
1146/**********************************************************************/
1147
1148/**
1149 * FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells
1150 *
1151 * This is the maximum value for #address-cells, #size-cells and
1152 * similar properties that will be processed by libfdt.  IEE1275
1153 * requires that OF implementations handle values up to 4.
1154 * Implementations may support larger values, but in practice higher
1155 * values aren't used.
1156 */
1157#define FDT_MAX_NCELLS		4
1158
1159/**
1160 * fdt_address_cells - retrieve address size for a bus represented in the tree
1161 * @fdt: pointer to the device tree blob
1162 * @nodeoffset: offset of the node to find the address size for
1163 *
1164 * When the node has a valid #address-cells property, returns its value.
1165 *
1166 * returns:
1167 *	0 <= n < FDT_MAX_NCELLS, on success
1168 *      2, if the node has no #address-cells property
1169 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1170 *		#address-cells property
1171 *	-FDT_ERR_BADMAGIC,
1172 *	-FDT_ERR_BADVERSION,
1173 *	-FDT_ERR_BADSTATE,
1174 *	-FDT_ERR_BADSTRUCTURE,
1175 *	-FDT_ERR_TRUNCATED, standard meanings
1176 */
1177int fdt_address_cells(const void *fdt, int nodeoffset);
1178
1179/**
1180 * fdt_size_cells - retrieve address range size for a bus represented in the
1181 *                  tree
1182 * @fdt: pointer to the device tree blob
1183 * @nodeoffset: offset of the node to find the address range size for
1184 *
1185 * When the node has a valid #size-cells property, returns its value.
1186 *
1187 * returns:
1188 *	0 <= n < FDT_MAX_NCELLS, on success
1189 *      1, if the node has no #size-cells property
1190 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1191 *		#size-cells property
1192 *	-FDT_ERR_BADMAGIC,
1193 *	-FDT_ERR_BADVERSION,
1194 *	-FDT_ERR_BADSTATE,
1195 *	-FDT_ERR_BADSTRUCTURE,
1196 *	-FDT_ERR_TRUNCATED, standard meanings
1197 */
1198int fdt_size_cells(const void *fdt, int nodeoffset);
1199
1200
1201/**********************************************************************/
1202/* Write-in-place functions                                           */
1203/**********************************************************************/
1204
1205/**
1206 * fdt_setprop_inplace_namelen_partial - change a property's value,
1207 *                                       but not its size
1208 * @fdt: pointer to the device tree blob
1209 * @nodeoffset: offset of the node whose property to change
1210 * @name: name of the property to change
1211 * @namelen: number of characters of name to consider
1212 * @idx: index of the property to change in the array
1213 * @val: pointer to data to replace the property value with
1214 * @len: length of the property value
1215 *
1216 * Identical to fdt_setprop_inplace(), but modifies the given property
1217 * starting from the given index, and using only the first characters
1218 * of the name. It is useful when you want to manipulate only one value of
1219 * an array and you have a string that doesn't end with \0.
 
 
1220 */
1221#ifndef SWIG /* Not available in Python */
1222int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
1223					const char *name, int namelen,
1224					uint32_t idx, const void *val,
1225					int len);
1226#endif
1227
1228/**
1229 * fdt_setprop_inplace - change a property's value, but not its size
1230 * @fdt: pointer to the device tree blob
1231 * @nodeoffset: offset of the node whose property to change
1232 * @name: name of the property to change
1233 * @val: pointer to data to replace the property value with
1234 * @len: length of the property value
1235 *
1236 * fdt_setprop_inplace() replaces the value of a given property with
1237 * the data in val, of length len.  This function cannot change the
1238 * size of a property, and so will only work if len is equal to the
1239 * current length of the property.
1240 *
1241 * This function will alter only the bytes in the blob which contain
1242 * the given property value, and will not alter or move any other part
1243 * of the tree.
1244 *
1245 * returns:
1246 *	0, on success
1247 *	-FDT_ERR_NOSPACE, if len is not equal to the property's current length
1248 *	-FDT_ERR_NOTFOUND, node does not have the named property
1249 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1250 *	-FDT_ERR_BADMAGIC,
1251 *	-FDT_ERR_BADVERSION,
1252 *	-FDT_ERR_BADSTATE,
1253 *	-FDT_ERR_BADSTRUCTURE,
1254 *	-FDT_ERR_TRUNCATED, standard meanings
1255 */
1256#ifndef SWIG /* Not available in Python */
1257int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
1258			const void *val, int len);
1259#endif
1260
1261/**
1262 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
1263 * @fdt: pointer to the device tree blob
1264 * @nodeoffset: offset of the node whose property to change
1265 * @name: name of the property to change
1266 * @val: 32-bit integer value to replace the property with
1267 *
1268 * fdt_setprop_inplace_u32() replaces the value of a given property
1269 * with the 32-bit integer value in val, converting val to big-endian
1270 * if necessary.  This function cannot change the size of a property,
1271 * and so will only work if the property already exists and has length
1272 * 4.
1273 *
1274 * This function will alter only the bytes in the blob which contain
1275 * the given property value, and will not alter or move any other part
1276 * of the tree.
1277 *
1278 * returns:
1279 *	0, on success
1280 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 4
1281 *	-FDT_ERR_NOTFOUND, node does not have the named property
1282 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1283 *	-FDT_ERR_BADMAGIC,
1284 *	-FDT_ERR_BADVERSION,
1285 *	-FDT_ERR_BADSTATE,
1286 *	-FDT_ERR_BADSTRUCTURE,
1287 *	-FDT_ERR_TRUNCATED, standard meanings
1288 */
1289static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
1290					  const char *name, uint32_t val)
1291{
1292	fdt32_t tmp = cpu_to_fdt32(val);
1293	return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1294}
1295
1296/**
1297 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
1298 * @fdt: pointer to the device tree blob
1299 * @nodeoffset: offset of the node whose property to change
1300 * @name: name of the property to change
1301 * @val: 64-bit integer value to replace the property with
1302 *
1303 * fdt_setprop_inplace_u64() replaces the value of a given property
1304 * with the 64-bit integer value in val, converting val to big-endian
1305 * if necessary.  This function cannot change the size of a property,
1306 * and so will only work if the property already exists and has length
1307 * 8.
1308 *
1309 * This function will alter only the bytes in the blob which contain
1310 * the given property value, and will not alter or move any other part
1311 * of the tree.
1312 *
1313 * returns:
1314 *	0, on success
1315 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 8
1316 *	-FDT_ERR_NOTFOUND, node does not have the named property
1317 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1318 *	-FDT_ERR_BADMAGIC,
1319 *	-FDT_ERR_BADVERSION,
1320 *	-FDT_ERR_BADSTATE,
1321 *	-FDT_ERR_BADSTRUCTURE,
1322 *	-FDT_ERR_TRUNCATED, standard meanings
1323 */
1324static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
1325					  const char *name, uint64_t val)
1326{
1327	fdt64_t tmp = cpu_to_fdt64(val);
1328	return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1329}
1330
1331/**
1332 * fdt_setprop_inplace_cell - change the value of a single-cell property
 
 
 
 
1333 *
1334 * This is an alternative name for fdt_setprop_inplace_u32()
 
1335 */
1336static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
1337					   const char *name, uint32_t val)
1338{
1339	return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
1340}
1341
1342/**
1343 * fdt_nop_property - replace a property with nop tags
1344 * @fdt: pointer to the device tree blob
1345 * @nodeoffset: offset of the node whose property to nop
1346 * @name: name of the property to nop
1347 *
1348 * fdt_nop_property() will replace a given property's representation
1349 * in the blob with FDT_NOP tags, effectively removing it from the
1350 * tree.
1351 *
1352 * This function will alter only the bytes in the blob which contain
1353 * the property, and will not alter or move any other part of the
1354 * tree.
1355 *
1356 * returns:
1357 *	0, on success
1358 *	-FDT_ERR_NOTFOUND, node does not have the named property
1359 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1360 *	-FDT_ERR_BADMAGIC,
1361 *	-FDT_ERR_BADVERSION,
1362 *	-FDT_ERR_BADSTATE,
1363 *	-FDT_ERR_BADSTRUCTURE,
1364 *	-FDT_ERR_TRUNCATED, standard meanings
1365 */
1366int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
1367
1368/**
1369 * fdt_nop_node - replace a node (subtree) with nop tags
1370 * @fdt: pointer to the device tree blob
1371 * @nodeoffset: offset of the node to nop
1372 *
1373 * fdt_nop_node() will replace a given node's representation in the
1374 * blob, including all its subnodes, if any, with FDT_NOP tags,
1375 * effectively removing it from the tree.
1376 *
1377 * This function will alter only the bytes in the blob which contain
1378 * the node and its properties and subnodes, and will not alter or
1379 * move any other part of the tree.
1380 *
1381 * returns:
1382 *	0, on success
1383 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1384 *	-FDT_ERR_BADMAGIC,
1385 *	-FDT_ERR_BADVERSION,
1386 *	-FDT_ERR_BADSTATE,
1387 *	-FDT_ERR_BADSTRUCTURE,
1388 *	-FDT_ERR_TRUNCATED, standard meanings
1389 */
1390int fdt_nop_node(void *fdt, int nodeoffset);
1391
1392/**********************************************************************/
1393/* Sequential write functions                                         */
1394/**********************************************************************/
1395
1396/* fdt_create_with_flags flags */
1397#define FDT_CREATE_FLAG_NO_NAME_DEDUP 0x1
1398	/* FDT_CREATE_FLAG_NO_NAME_DEDUP: Do not try to de-duplicate property
1399	 * names in the fdt. This can result in faster creation times, but
1400	 * a larger fdt. */
1401
1402#define FDT_CREATE_FLAGS_ALL	(FDT_CREATE_FLAG_NO_NAME_DEDUP)
1403
1404/**
1405 * fdt_create_with_flags - begin creation of a new fdt
1406 * @fdt: pointer to memory allocated where fdt will be created
1407 * @bufsize: size of the memory space at fdt
1408 * @flags: a valid combination of FDT_CREATE_FLAG_ flags, or 0.
1409 *
1410 * fdt_create_with_flags() begins the process of creating a new fdt with
1411 * the sequential write interface.
1412 *
1413 * fdt creation process must end with fdt_finished() to produce a valid fdt.
1414 *
1415 * returns:
1416 *	0, on success
1417 *	-FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1418 *	-FDT_ERR_BADFLAGS, flags is not valid
1419 */
1420int fdt_create_with_flags(void *buf, int bufsize, uint32_t flags);
1421
1422/**
1423 * fdt_create - begin creation of a new fdt
1424 * @fdt: pointer to memory allocated where fdt will be created
1425 * @bufsize: size of the memory space at fdt
1426 *
1427 * fdt_create() is equivalent to fdt_create_with_flags() with flags=0.
1428 *
1429 * returns:
1430 *	0, on success
1431 *	-FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1432 */
1433int fdt_create(void *buf, int bufsize);
1434
1435int fdt_resize(void *fdt, void *buf, int bufsize);
1436int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
1437int fdt_finish_reservemap(void *fdt);
1438int fdt_begin_node(void *fdt, const char *name);
1439int fdt_property(void *fdt, const char *name, const void *val, int len);
1440static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
1441{
1442	fdt32_t tmp = cpu_to_fdt32(val);
1443	return fdt_property(fdt, name, &tmp, sizeof(tmp));
1444}
1445static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
1446{
1447	fdt64_t tmp = cpu_to_fdt64(val);
1448	return fdt_property(fdt, name, &tmp, sizeof(tmp));
1449}
1450
1451#ifndef SWIG /* Not available in Python */
1452static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
1453{
1454	return fdt_property_u32(fdt, name, val);
1455}
1456#endif
1457
1458/**
1459 * fdt_property_placeholder - add a new property and return a ptr to its value
1460 *
1461 * @fdt: pointer to the device tree blob
1462 * @name: name of property to add
1463 * @len: length of property value in bytes
1464 * @valp: returns a pointer to where where the value should be placed
1465 *
1466 * returns:
1467 *	0, on success
1468 *	-FDT_ERR_BADMAGIC,
1469 *	-FDT_ERR_NOSPACE, standard meanings
1470 */
1471int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp);
1472
1473#define fdt_property_string(fdt, name, str) \
1474	fdt_property(fdt, name, str, strlen(str)+1)
1475int fdt_end_node(void *fdt);
1476int fdt_finish(void *fdt);
1477
1478/**********************************************************************/
1479/* Read-write functions                                               */
1480/**********************************************************************/
1481
1482int fdt_create_empty_tree(void *buf, int bufsize);
1483int fdt_open_into(const void *fdt, void *buf, int bufsize);
1484int fdt_pack(void *fdt);
1485
1486/**
1487 * fdt_add_mem_rsv - add one memory reserve map entry
1488 * @fdt: pointer to the device tree blob
1489 * @address, @size: 64-bit values (native endian)
 
1490 *
1491 * Adds a reserve map entry to the given blob reserving a region at
1492 * address address of length size.
1493 *
1494 * This function will insert data into the reserve map and will
1495 * therefore change the indexes of some entries in the table.
1496 *
1497 * returns:
1498 *	0, on success
1499 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1500 *		contain the new reservation entry
1501 *	-FDT_ERR_BADMAGIC,
1502 *	-FDT_ERR_BADVERSION,
1503 *	-FDT_ERR_BADSTATE,
1504 *	-FDT_ERR_BADSTRUCTURE,
1505 *	-FDT_ERR_BADLAYOUT,
1506 *	-FDT_ERR_TRUNCATED, standard meanings
1507 */
1508int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
1509
1510/**
1511 * fdt_del_mem_rsv - remove a memory reserve map entry
1512 * @fdt: pointer to the device tree blob
1513 * @n: entry to remove
1514 *
1515 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
1516 * the blob.
1517 *
1518 * This function will delete data from the reservation table and will
1519 * therefore change the indexes of some entries in the table.
1520 *
1521 * returns:
1522 *	0, on success
1523 *	-FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
1524 *		are less than n+1 reserve map entries)
1525 *	-FDT_ERR_BADMAGIC,
1526 *	-FDT_ERR_BADVERSION,
1527 *	-FDT_ERR_BADSTATE,
1528 *	-FDT_ERR_BADSTRUCTURE,
1529 *	-FDT_ERR_BADLAYOUT,
1530 *	-FDT_ERR_TRUNCATED, standard meanings
1531 */
1532int fdt_del_mem_rsv(void *fdt, int n);
1533
1534/**
1535 * fdt_set_name - change the name of a given node
1536 * @fdt: pointer to the device tree blob
1537 * @nodeoffset: structure block offset of a node
1538 * @name: name to give the node
1539 *
1540 * fdt_set_name() replaces the name (including unit address, if any)
1541 * of the given node with the given string.  NOTE: this function can't
1542 * efficiently check if the new name is unique amongst the given
1543 * node's siblings; results are undefined if this function is invoked
1544 * with a name equal to one of the given node's siblings.
1545 *
1546 * This function may insert or delete data from the blob, and will
1547 * therefore change the offsets of some existing nodes.
1548 *
1549 * returns:
1550 *	0, on success
1551 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob
1552 *		to contain the new name
1553 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1554 *	-FDT_ERR_BADMAGIC,
1555 *	-FDT_ERR_BADVERSION,
1556 *	-FDT_ERR_BADSTATE, standard meanings
1557 */
1558int fdt_set_name(void *fdt, int nodeoffset, const char *name);
1559
1560/**
1561 * fdt_setprop - create or change a property
1562 * @fdt: pointer to the device tree blob
1563 * @nodeoffset: offset of the node whose property to change
1564 * @name: name of the property to change
1565 * @val: pointer to data to set the property value to
1566 * @len: length of the property value
1567 *
1568 * fdt_setprop() sets the value of the named property in the given
1569 * node to the given value and length, creating the property if it
1570 * does not already exist.
1571 *
1572 * This function may insert or delete data from the blob, and will
1573 * therefore change the offsets of some existing nodes.
1574 *
1575 * returns:
1576 *	0, on success
1577 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1578 *		contain the new property value
1579 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1580 *	-FDT_ERR_BADLAYOUT,
1581 *	-FDT_ERR_BADMAGIC,
1582 *	-FDT_ERR_BADVERSION,
1583 *	-FDT_ERR_BADSTATE,
1584 *	-FDT_ERR_BADSTRUCTURE,
1585 *	-FDT_ERR_BADLAYOUT,
1586 *	-FDT_ERR_TRUNCATED, standard meanings
1587 */
1588int fdt_setprop(void *fdt, int nodeoffset, const char *name,
1589		const void *val, int len);
1590
1591/**
1592 * fdt_setprop_placeholder - allocate space for a property
1593 * @fdt: pointer to the device tree blob
1594 * @nodeoffset: offset of the node whose property to change
1595 * @name: name of the property to change
1596 * @len: length of the property value
1597 * @prop_data: return pointer to property data
1598 *
1599 * fdt_setprop_placeholer() allocates the named property in the given node.
1600 * If the property exists it is resized. In either case a pointer to the
1601 * property data is returned.
1602 *
1603 * This function may insert or delete data from the blob, and will
1604 * therefore change the offsets of some existing nodes.
1605 *
1606 * returns:
1607 *	0, on success
1608 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1609 *		contain the new property value
1610 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1611 *	-FDT_ERR_BADLAYOUT,
1612 *	-FDT_ERR_BADMAGIC,
1613 *	-FDT_ERR_BADVERSION,
1614 *	-FDT_ERR_BADSTATE,
1615 *	-FDT_ERR_BADSTRUCTURE,
1616 *	-FDT_ERR_BADLAYOUT,
1617 *	-FDT_ERR_TRUNCATED, standard meanings
1618 */
1619int fdt_setprop_placeholder(void *fdt, int nodeoffset, const char *name,
1620			    int len, void **prop_data);
1621
1622/**
1623 * fdt_setprop_u32 - set a property to a 32-bit integer
1624 * @fdt: pointer to the device tree blob
1625 * @nodeoffset: offset of the node whose property to change
1626 * @name: name of the property to change
1627 * @val: 32-bit integer value for the property (native endian)
1628 *
1629 * fdt_setprop_u32() sets the value of the named property in the given
1630 * node to the given 32-bit integer value (converting to big-endian if
1631 * necessary), or creates a new property with that value if it does
1632 * not already exist.
1633 *
1634 * This function may insert or delete data from the blob, and will
1635 * therefore change the offsets of some existing nodes.
1636 *
1637 * returns:
1638 *	0, on success
1639 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1640 *		contain the new property value
1641 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1642 *	-FDT_ERR_BADLAYOUT,
1643 *	-FDT_ERR_BADMAGIC,
1644 *	-FDT_ERR_BADVERSION,
1645 *	-FDT_ERR_BADSTATE,
1646 *	-FDT_ERR_BADSTRUCTURE,
1647 *	-FDT_ERR_BADLAYOUT,
1648 *	-FDT_ERR_TRUNCATED, standard meanings
1649 */
1650static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
1651				  uint32_t val)
1652{
1653	fdt32_t tmp = cpu_to_fdt32(val);
1654	return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1655}
1656
1657/**
1658 * fdt_setprop_u64 - set a property to a 64-bit integer
1659 * @fdt: pointer to the device tree blob
1660 * @nodeoffset: offset of the node whose property to change
1661 * @name: name of the property to change
1662 * @val: 64-bit integer value for the property (native endian)
1663 *
1664 * fdt_setprop_u64() sets the value of the named property in the given
1665 * node to the given 64-bit integer value (converting to big-endian if
1666 * necessary), or creates a new property with that value if it does
1667 * not already exist.
1668 *
1669 * This function may insert or delete data from the blob, and will
1670 * therefore change the offsets of some existing nodes.
1671 *
1672 * returns:
1673 *	0, on success
1674 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1675 *		contain the new property value
1676 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1677 *	-FDT_ERR_BADLAYOUT,
1678 *	-FDT_ERR_BADMAGIC,
1679 *	-FDT_ERR_BADVERSION,
1680 *	-FDT_ERR_BADSTATE,
1681 *	-FDT_ERR_BADSTRUCTURE,
1682 *	-FDT_ERR_BADLAYOUT,
1683 *	-FDT_ERR_TRUNCATED, standard meanings
1684 */
1685static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
1686				  uint64_t val)
1687{
1688	fdt64_t tmp = cpu_to_fdt64(val);
1689	return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1690}
1691
1692/**
1693 * fdt_setprop_cell - set a property to a single cell value
 
 
 
 
1694 *
1695 * This is an alternative name for fdt_setprop_u32()
 
 
1696 */
1697static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
1698				   uint32_t val)
1699{
1700	return fdt_setprop_u32(fdt, nodeoffset, name, val);
1701}
1702
1703/**
1704 * fdt_setprop_string - set a property to a string value
1705 * @fdt: pointer to the device tree blob
1706 * @nodeoffset: offset of the node whose property to change
1707 * @name: name of the property to change
1708 * @str: string value for the property
1709 *
1710 * fdt_setprop_string() sets the value of the named property in the
1711 * given node to the given string value (using the length of the
1712 * string to determine the new length of the property), or creates a
1713 * new property with that value if it does not already exist.
1714 *
1715 * This function may insert or delete data from the blob, and will
1716 * therefore change the offsets of some existing nodes.
1717 *
1718 * returns:
1719 *	0, on success
1720 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1721 *		contain the new property value
1722 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1723 *	-FDT_ERR_BADLAYOUT,
1724 *	-FDT_ERR_BADMAGIC,
1725 *	-FDT_ERR_BADVERSION,
1726 *	-FDT_ERR_BADSTATE,
1727 *	-FDT_ERR_BADSTRUCTURE,
1728 *	-FDT_ERR_BADLAYOUT,
1729 *	-FDT_ERR_TRUNCATED, standard meanings
1730 */
1731#define fdt_setprop_string(fdt, nodeoffset, name, str) \
1732	fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1733
1734
1735/**
1736 * fdt_setprop_empty - set a property to an empty value
1737 * @fdt: pointer to the device tree blob
1738 * @nodeoffset: offset of the node whose property to change
1739 * @name: name of the property to change
1740 *
1741 * fdt_setprop_empty() sets the value of the named property in the
1742 * given node to an empty (zero length) value, or creates a new empty
1743 * property if it does not already exist.
1744 *
1745 * This function may insert or delete data from the blob, and will
1746 * therefore change the offsets of some existing nodes.
1747 *
1748 * returns:
1749 *	0, on success
1750 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1751 *		contain the new property value
1752 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1753 *	-FDT_ERR_BADLAYOUT,
1754 *	-FDT_ERR_BADMAGIC,
1755 *	-FDT_ERR_BADVERSION,
1756 *	-FDT_ERR_BADSTATE,
1757 *	-FDT_ERR_BADSTRUCTURE,
1758 *	-FDT_ERR_BADLAYOUT,
1759 *	-FDT_ERR_TRUNCATED, standard meanings
1760 */
1761#define fdt_setprop_empty(fdt, nodeoffset, name) \
1762	fdt_setprop((fdt), (nodeoffset), (name), NULL, 0)
1763
1764/**
1765 * fdt_appendprop - append to or create a property
1766 * @fdt: pointer to the device tree blob
1767 * @nodeoffset: offset of the node whose property to change
1768 * @name: name of the property to append to
1769 * @val: pointer to data to append to the property value
1770 * @len: length of the data to append to the property value
1771 *
1772 * fdt_appendprop() appends the value to the named property in the
1773 * given node, creating the property if it does not already exist.
1774 *
1775 * This function may insert data into the blob, and will therefore
1776 * change the offsets of some existing nodes.
1777 *
1778 * returns:
1779 *	0, on success
1780 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1781 *		contain the new property value
1782 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1783 *	-FDT_ERR_BADLAYOUT,
1784 *	-FDT_ERR_BADMAGIC,
1785 *	-FDT_ERR_BADVERSION,
1786 *	-FDT_ERR_BADSTATE,
1787 *	-FDT_ERR_BADSTRUCTURE,
1788 *	-FDT_ERR_BADLAYOUT,
1789 *	-FDT_ERR_TRUNCATED, standard meanings
1790 */
1791int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
1792		   const void *val, int len);
1793
1794/**
1795 * fdt_appendprop_u32 - append a 32-bit integer value to a property
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 to append to the property (native endian)
1800 *
1801 * fdt_appendprop_u32() appends the given 32-bit integer value
1802 * (converting to big-endian if necessary) to the value of the named
1803 * property in the given node, or creates a new property with that
1804 * value if it does not already exist.
1805 *
1806 * This function may insert data into the blob, and will therefore
1807 * change the offsets of some existing nodes.
1808 *
1809 * returns:
1810 *	0, on success
1811 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1812 *		contain the new property value
1813 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1814 *	-FDT_ERR_BADLAYOUT,
1815 *	-FDT_ERR_BADMAGIC,
1816 *	-FDT_ERR_BADVERSION,
1817 *	-FDT_ERR_BADSTATE,
1818 *	-FDT_ERR_BADSTRUCTURE,
1819 *	-FDT_ERR_BADLAYOUT,
1820 *	-FDT_ERR_TRUNCATED, standard meanings
1821 */
1822static inline int fdt_appendprop_u32(void *fdt, int nodeoffset,
1823				     const char *name, uint32_t val)
1824{
1825	fdt32_t tmp = cpu_to_fdt32(val);
1826	return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1827}
1828
1829/**
1830 * fdt_appendprop_u64 - append a 64-bit integer value to a property
1831 * @fdt: pointer to the device tree blob
1832 * @nodeoffset: offset of the node whose property to change
1833 * @name: name of the property to change
1834 * @val: 64-bit integer value to append to the property (native endian)
1835 *
1836 * fdt_appendprop_u64() appends the given 64-bit integer value
1837 * (converting to big-endian if necessary) to the value of the named
1838 * property in the given node, or creates a new property with that
1839 * value if it does not already exist.
1840 *
1841 * This function may insert data into the blob, and will therefore
1842 * change the offsets of some existing nodes.
1843 *
1844 * returns:
1845 *	0, on success
1846 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1847 *		contain the new property value
1848 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1849 *	-FDT_ERR_BADLAYOUT,
1850 *	-FDT_ERR_BADMAGIC,
1851 *	-FDT_ERR_BADVERSION,
1852 *	-FDT_ERR_BADSTATE,
1853 *	-FDT_ERR_BADSTRUCTURE,
1854 *	-FDT_ERR_BADLAYOUT,
1855 *	-FDT_ERR_TRUNCATED, standard meanings
1856 */
1857static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
1858				     const char *name, uint64_t val)
1859{
1860	fdt64_t tmp = cpu_to_fdt64(val);
1861	return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1862}
1863
1864/**
1865 * fdt_appendprop_cell - append a single cell value to a property
 
 
 
 
1866 *
1867 * This is an alternative name for fdt_appendprop_u32()
 
 
1868 */
1869static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
1870				      const char *name, uint32_t val)
1871{
1872	return fdt_appendprop_u32(fdt, nodeoffset, name, val);
1873}
1874
1875/**
1876 * fdt_appendprop_string - append a string to a property
1877 * @fdt: pointer to the device tree blob
1878 * @nodeoffset: offset of the node whose property to change
1879 * @name: name of the property to change
1880 * @str: string value to append to the property
1881 *
1882 * fdt_appendprop_string() appends the given string to the value of
1883 * the named property in the given node, or creates a new property
1884 * with that value if it does not already exist.
1885 *
1886 * This function may insert data into the blob, and will therefore
1887 * change the offsets of some existing nodes.
1888 *
1889 * returns:
1890 *	0, on success
1891 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1892 *		contain the new property value
1893 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1894 *	-FDT_ERR_BADLAYOUT,
1895 *	-FDT_ERR_BADMAGIC,
1896 *	-FDT_ERR_BADVERSION,
1897 *	-FDT_ERR_BADSTATE,
1898 *	-FDT_ERR_BADSTRUCTURE,
1899 *	-FDT_ERR_BADLAYOUT,
1900 *	-FDT_ERR_TRUNCATED, standard meanings
1901 */
1902#define fdt_appendprop_string(fdt, nodeoffset, name, str) \
1903	fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1904
1905/**
1906 * fdt_appendprop_addrrange - append a address range property
1907 * @fdt: pointer to the device tree blob
1908 * @parent: offset of the parent node
1909 * @nodeoffset: offset of the node to add a property at
1910 * @name: name of property
1911 * @addr: start address of a given range
1912 * @size: size of a given range
1913 *
1914 * fdt_appendprop_addrrange() appends an address range value (start
1915 * address and size) to the value of the named property in the given
1916 * node, or creates a new property with that value if it does not
1917 * already exist.
1918 * If "name" is not specified, a default "reg" is used.
1919 * Cell sizes are determined by parent's #address-cells and #size-cells.
1920 *
1921 * This function may insert data into the blob, and will therefore
1922 * change the offsets of some existing nodes.
1923 *
1924 * returns:
1925 *	0, on success
1926 *	-FDT_ERR_BADLAYOUT,
1927 *	-FDT_ERR_BADMAGIC,
1928 *	-FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1929 *		#address-cells property
1930 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1931 *	-FDT_ERR_BADSTATE,
1932 *	-FDT_ERR_BADSTRUCTURE,
1933 *	-FDT_ERR_BADVERSION,
1934 *	-FDT_ERR_BADVALUE, addr or size doesn't fit to respective cells size
1935 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1936 *		contain a new property
1937 *	-FDT_ERR_TRUNCATED, standard meanings
1938 */
1939int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
1940			     const char *name, uint64_t addr, uint64_t size);
1941
1942/**
1943 * fdt_delprop - delete a property
1944 * @fdt: pointer to the device tree blob
1945 * @nodeoffset: offset of the node whose property to nop
1946 * @name: name of the property to nop
1947 *
1948 * fdt_del_property() will delete the given property.
1949 *
1950 * This function will delete data from the blob, and will therefore
1951 * change the offsets of some existing nodes.
1952 *
1953 * returns:
1954 *	0, on success
1955 *	-FDT_ERR_NOTFOUND, node does not have the named property
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_TRUNCATED, standard meanings
1963 */
1964int fdt_delprop(void *fdt, int nodeoffset, const char *name);
1965
1966/**
1967 * fdt_add_subnode_namelen - creates a new node based on substring
1968 * @fdt: pointer to the device tree blob
1969 * @parentoffset: structure block offset of a node
1970 * @name: name of the subnode to locate
1971 * @namelen: number of characters of name to consider
1972 *
1973 * Identical to fdt_add_subnode(), but use only the first namelen
1974 * characters of name as the name of the new node.  This is useful for
1975 * creating subnodes based on a portion of a larger string, such as a
1976 * full path.
 
 
 
1977 */
1978#ifndef SWIG /* Not available in Python */
1979int fdt_add_subnode_namelen(void *fdt, int parentoffset,
1980			    const char *name, int namelen);
1981#endif
1982
1983/**
1984 * fdt_add_subnode - creates a new node
1985 * @fdt: pointer to the device tree blob
1986 * @parentoffset: structure block offset of a node
1987 * @name: name of the subnode to locate
1988 *
1989 * fdt_add_subnode() creates a new node as a subnode of the node at
1990 * structure block offset parentoffset, with the given name (which
1991 * should include the unit address, if any).
1992 *
1993 * This function will insert data into the blob, and will therefore
1994 * change the offsets of some existing nodes.
1995
1996 * returns:
1997 *	structure block offset of the created nodeequested subnode (>=0), on
1998 *		success
1999 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
2000 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
2001 *		tag
2002 *	-FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
2003 *		the given name
2004 *	-FDT_ERR_NOSPACE, if there is insufficient free space in the
2005 *		blob to contain the new node
2006 *	-FDT_ERR_NOSPACE
2007 *	-FDT_ERR_BADLAYOUT
2008 *      -FDT_ERR_BADMAGIC,
2009 *	-FDT_ERR_BADVERSION,
2010 *	-FDT_ERR_BADSTATE,
2011 *	-FDT_ERR_BADSTRUCTURE,
2012 *	-FDT_ERR_TRUNCATED, standard meanings.
2013 */
2014int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
2015
2016/**
2017 * fdt_del_node - delete a node (subtree)
2018 * @fdt: pointer to the device tree blob
2019 * @nodeoffset: offset of the node to nop
2020 *
2021 * fdt_del_node() will remove the given node, including all its
2022 * subnodes if any, from the blob.
2023 *
2024 * This function will delete data from the blob, and will therefore
2025 * change the offsets of some existing nodes.
2026 *
2027 * returns:
2028 *	0, on success
2029 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2030 *	-FDT_ERR_BADLAYOUT,
2031 *	-FDT_ERR_BADMAGIC,
2032 *	-FDT_ERR_BADVERSION,
2033 *	-FDT_ERR_BADSTATE,
2034 *	-FDT_ERR_BADSTRUCTURE,
2035 *	-FDT_ERR_TRUNCATED, standard meanings
2036 */
2037int fdt_del_node(void *fdt, int nodeoffset);
2038
2039/**
2040 * fdt_overlay_apply - Applies a DT overlay on a base DT
2041 * @fdt: pointer to the base device tree blob
2042 * @fdto: pointer to the device tree overlay blob
2043 *
2044 * fdt_overlay_apply() will apply the given device tree overlay on the
2045 * given base device tree.
2046 *
2047 * Expect the base device tree to be modified, even if the function
2048 * returns an error.
2049 *
2050 * returns:
2051 *	0, on success
2052 *	-FDT_ERR_NOSPACE, there's not enough space in the base device tree
2053 *	-FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
2054 *		properties in the base DT
2055 *	-FDT_ERR_BADPHANDLE,
2056 *	-FDT_ERR_BADOVERLAY,
2057 *	-FDT_ERR_NOPHANDLES,
2058 *	-FDT_ERR_INTERNAL,
2059 *	-FDT_ERR_BADLAYOUT,
2060 *	-FDT_ERR_BADMAGIC,
2061 *	-FDT_ERR_BADOFFSET,
2062 *	-FDT_ERR_BADPATH,
2063 *	-FDT_ERR_BADVERSION,
2064 *	-FDT_ERR_BADSTRUCTURE,
2065 *	-FDT_ERR_BADSTATE,
2066 *	-FDT_ERR_TRUNCATED, standard meanings
2067 */
2068int fdt_overlay_apply(void *fdt, void *fdto);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2069
2070/**********************************************************************/
2071/* Debugging / informational functions                                */
2072/**********************************************************************/
2073
2074const char *fdt_strerror(int errval);
2075
2076#ifdef __cplusplus
2077}
2078#endif
2079
2080#endif /* LIBFDT_H */