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   1#ifndef LIBFDT_H
   2#define LIBFDT_H
   3/*
   4 * libfdt - Flat Device Tree manipulation
   5 * Copyright (C) 2006 David Gibson, IBM Corporation.
   6 *
   7 * libfdt is dual licensed: you can use it either under the terms of
   8 * the GPL, or the BSD license, at your option.
   9 *
  10 *  a) This library is free software; you can redistribute it and/or
  11 *     modify it under the terms of the GNU General Public License as
  12 *     published by the Free Software Foundation; either version 2 of the
  13 *     License, or (at your option) any later version.
  14 *
  15 *     This library is distributed in the hope that it will be useful,
  16 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 *     GNU General Public License for more details.
  19 *
  20 *     You should have received a copy of the GNU General Public
  21 *     License along with this library; if not, write to the Free
  22 *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  23 *     MA 02110-1301 USA
  24 *
  25 * Alternatively,
  26 *
  27 *  b) Redistribution and use in source and binary forms, with or
  28 *     without modification, are permitted provided that the following
  29 *     conditions are met:
  30 *
  31 *     1. Redistributions of source code must retain the above
  32 *        copyright notice, this list of conditions and the following
  33 *        disclaimer.
  34 *     2. Redistributions in binary form must reproduce the above
  35 *        copyright notice, this list of conditions and the following
  36 *        disclaimer in the documentation and/or other materials
  37 *        provided with the distribution.
  38 *
  39 *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  40 *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  41 *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  42 *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  43 *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  44 *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45 *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46 *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47 *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48 *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  49 *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  50 *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
  51 *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  52 */
  53
  54#include "libfdt_env.h"
  55#include "fdt.h"
  56
 
 
 
 
  57#define FDT_FIRST_SUPPORTED_VERSION	0x02
  58#define FDT_LAST_SUPPORTED_VERSION	0x11
  59
  60/* Error codes: informative error codes */
  61#define FDT_ERR_NOTFOUND	1
  62	/* FDT_ERR_NOTFOUND: The requested node or property does not exist */
  63#define FDT_ERR_EXISTS		2
  64	/* FDT_ERR_EXISTS: Attempted to create a node or property which
  65	 * already exists */
  66#define FDT_ERR_NOSPACE		3
  67	/* FDT_ERR_NOSPACE: Operation needed to expand the device
  68	 * tree, but its buffer did not have sufficient space to
  69	 * contain the expanded tree. Use fdt_open_into() to move the
  70	 * device tree to a buffer with more space. */
  71
  72/* Error codes: codes for bad parameters */
  73#define FDT_ERR_BADOFFSET	4
  74	/* FDT_ERR_BADOFFSET: Function was passed a structure block
  75	 * offset which is out-of-bounds, or which points to an
  76	 * unsuitable part of the structure for the operation. */
  77#define FDT_ERR_BADPATH		5
  78	/* FDT_ERR_BADPATH: Function was passed a badly formatted path
  79	 * (e.g. missing a leading / for a function which requires an
  80	 * absolute path) */
  81#define FDT_ERR_BADPHANDLE	6
  82	/* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle.
  83	 * This can be caused either by an invalid phandle property
  84	 * length, or the phandle value was either 0 or -1, which are
  85	 * not permitted. */
  86#define FDT_ERR_BADSTATE	7
  87	/* FDT_ERR_BADSTATE: Function was passed an incomplete device
  88	 * tree created by the sequential-write functions, which is
  89	 * not sufficiently complete for the requested operation. */
  90
  91/* Error codes: codes for bad device tree blobs */
  92#define FDT_ERR_TRUNCATED	8
  93	/* FDT_ERR_TRUNCATED: Structure block of the given device tree
  94	 * ends without an FDT_END tag. */
 
  95#define FDT_ERR_BADMAGIC	9
  96	/* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
  97	 * device tree at all - it is missing the flattened device
  98	 * tree magic number. */
  99#define FDT_ERR_BADVERSION	10
 100	/* FDT_ERR_BADVERSION: Given device tree has a version which
 101	 * can't be handled by the requested operation.  For
 102	 * read-write functions, this may mean that fdt_open_into() is
 103	 * required to convert the tree to the expected version. */
 104#define FDT_ERR_BADSTRUCTURE	11
 105	/* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt
 106	 * structure block or other serious error (e.g. misnested
 107	 * nodes, or subnodes preceding properties). */
 108#define FDT_ERR_BADLAYOUT	12
 109	/* FDT_ERR_BADLAYOUT: For read-write functions, the given
 110	 * device tree has it's sub-blocks in an order that the
 111	 * function can't handle (memory reserve map, then structure,
 112	 * then strings).  Use fdt_open_into() to reorganize the tree
 113	 * into a form suitable for the read-write operations. */
 114
 115/* "Can't happen" error indicating a bug in libfdt */
 116#define FDT_ERR_INTERNAL	13
 117	/* FDT_ERR_INTERNAL: libfdt has failed an internal assertion.
 118	 * Should never be returned, if it is, it indicates a bug in
 119	 * libfdt itself. */
 120
 121/* Errors in device tree content */
 122#define FDT_ERR_BADNCELLS	14
 123	/* FDT_ERR_BADNCELLS: Device tree has a #address-cells, #size-cells
 124	 * or similar property with a bad format or value */
 125
 126#define FDT_ERR_BADVALUE	15
 127	/* FDT_ERR_BADVALUE: Device tree has a property with an unexpected
 128	 * value. For example: a property expected to contain a string list
 129	 * is not NUL-terminated within the length of its value. */
 130
 131#define FDT_ERR_BADOVERLAY	16
 132	/* FDT_ERR_BADOVERLAY: The device tree overlay, while
 133	 * correctly structured, cannot be applied due to some
 134	 * unexpected or missing value, property or node. */
 135
 136#define FDT_ERR_NOPHANDLES	17
 137	/* FDT_ERR_NOPHANDLES: The device tree doesn't have any
 138	 * phandle available anymore without causing an overflow */
 139
 140#define FDT_ERR_MAX		17
 
 
 
 
 
 
 
 
 141
 142/**********************************************************************/
 143/* Low-level functions (you probably don't need these)                */
 144/**********************************************************************/
 145
 146#ifndef SWIG /* This function is not useful in Python */
 147const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen);
 148#endif
 149static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
 150{
 151	return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
 152}
 153
 154uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
 155
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 156/**********************************************************************/
 157/* Traversal functions                                                */
 158/**********************************************************************/
 159
 160int fdt_next_node(const void *fdt, int offset, int *depth);
 161
 162/**
 163 * fdt_first_subnode() - get offset of first direct subnode
 164 *
 165 * @fdt:	FDT blob
 166 * @offset:	Offset of node to check
 167 * @return offset of first subnode, or -FDT_ERR_NOTFOUND if there is none
 168 */
 169int fdt_first_subnode(const void *fdt, int offset);
 170
 171/**
 172 * fdt_next_subnode() - get offset of next direct subnode
 173 *
 174 * After first calling fdt_first_subnode(), call this function repeatedly to
 175 * get direct subnodes of a parent node.
 176 *
 177 * @fdt:	FDT blob
 178 * @offset:	Offset of previous subnode
 179 * @return offset of next subnode, or -FDT_ERR_NOTFOUND if there are no more
 180 * subnodes
 181 */
 182int fdt_next_subnode(const void *fdt, int offset);
 183
 184/**
 185 * fdt_for_each_subnode - iterate over all subnodes of a parent
 186 *
 187 * @node:	child node (int, lvalue)
 188 * @fdt:	FDT blob (const void *)
 189 * @parent:	parent node (int)
 190 *
 191 * This is actually a wrapper around a for loop and would be used like so:
 192 *
 193 *	fdt_for_each_subnode(node, fdt, parent) {
 194 *		Use node
 195 *		...
 196 *	}
 197 *
 198 *	if ((node < 0) && (node != -FDT_ERR_NOT_FOUND)) {
 199 *		Error handling
 200 *	}
 201 *
 202 * Note that this is implemented as a macro and @node is used as
 203 * iterator in the loop. The parent variable be constant or even a
 204 * literal.
 205 *
 206 */
 207#define fdt_for_each_subnode(node, fdt, parent)		\
 208	for (node = fdt_first_subnode(fdt, parent);	\
 209	     node >= 0;					\
 210	     node = fdt_next_subnode(fdt, node))
 211
 212/**********************************************************************/
 213/* General functions                                                  */
 214/**********************************************************************/
 215#define fdt_get_header(fdt, field) \
 216	(fdt32_to_cpu(((const struct fdt_header *)(fdt))->field))
 217#define fdt_magic(fdt)			(fdt_get_header(fdt, magic))
 218#define fdt_totalsize(fdt)		(fdt_get_header(fdt, totalsize))
 219#define fdt_off_dt_struct(fdt)		(fdt_get_header(fdt, off_dt_struct))
 220#define fdt_off_dt_strings(fdt)		(fdt_get_header(fdt, off_dt_strings))
 221#define fdt_off_mem_rsvmap(fdt)		(fdt_get_header(fdt, off_mem_rsvmap))
 222#define fdt_version(fdt)		(fdt_get_header(fdt, version))
 223#define fdt_last_comp_version(fdt)	(fdt_get_header(fdt, last_comp_version))
 224#define fdt_boot_cpuid_phys(fdt)	(fdt_get_header(fdt, boot_cpuid_phys))
 225#define fdt_size_dt_strings(fdt)	(fdt_get_header(fdt, size_dt_strings))
 226#define fdt_size_dt_struct(fdt)		(fdt_get_header(fdt, size_dt_struct))
 227
 228#define fdt_set_hdr_(name) \
 229	static inline void fdt_set_##name(void *fdt, uint32_t val) \
 230	{ \
 231		struct fdt_header *fdth = (struct fdt_header *)fdt; \
 232		fdth->name = cpu_to_fdt32(val); \
 233	}
 234fdt_set_hdr_(magic);
 235fdt_set_hdr_(totalsize);
 236fdt_set_hdr_(off_dt_struct);
 237fdt_set_hdr_(off_dt_strings);
 238fdt_set_hdr_(off_mem_rsvmap);
 239fdt_set_hdr_(version);
 240fdt_set_hdr_(last_comp_version);
 241fdt_set_hdr_(boot_cpuid_phys);
 242fdt_set_hdr_(size_dt_strings);
 243fdt_set_hdr_(size_dt_struct);
 244#undef fdt_set_hdr_
 245
 246/**
 247 * fdt_check_header - sanity check a device tree or possible device tree
 
 
 
 
 
 
 
 
 
 
 
 
 248 * @fdt: pointer to data which might be a flattened device tree
 249 *
 250 * fdt_check_header() checks that the given buffer contains what
 251 * appears to be a flattened device tree with sane information in its
 252 * header.
 
 253 *
 254 * returns:
 255 *     0, if the buffer appears to contain a valid device tree
 256 *     -FDT_ERR_BADMAGIC,
 257 *     -FDT_ERR_BADVERSION,
 258 *     -FDT_ERR_BADSTATE, standard meanings, as above
 
 259 */
 260int fdt_check_header(const void *fdt);
 261
 262/**
 263 * fdt_move - move a device tree around in memory
 264 * @fdt: pointer to the device tree to move
 265 * @buf: pointer to memory where the device is to be moved
 266 * @bufsize: size of the memory space at buf
 267 *
 268 * fdt_move() relocates, if possible, the device tree blob located at
 269 * fdt to the buffer at buf of size bufsize.  The buffer may overlap
 270 * with the existing device tree blob at fdt.  Therefore,
 271 *     fdt_move(fdt, fdt, fdt_totalsize(fdt))
 272 * should always succeed.
 273 *
 274 * returns:
 275 *     0, on success
 276 *     -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
 277 *     -FDT_ERR_BADMAGIC,
 278 *     -FDT_ERR_BADVERSION,
 279 *     -FDT_ERR_BADSTATE, standard meanings
 280 */
 281int fdt_move(const void *fdt, void *buf, int bufsize);
 282
 283/**********************************************************************/
 284/* Read-only functions                                                */
 285/**********************************************************************/
 286
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 287/**
 288 * fdt_string - retrieve a string from the strings block of a device tree
 289 * @fdt: pointer to the device tree blob
 290 * @stroffset: offset of the string within the strings block (native endian)
 291 *
 292 * fdt_string() retrieves a pointer to a single string from the
 293 * strings block of the device tree blob at fdt.
 294 *
 295 * returns:
 296 *     a pointer to the string, on success
 297 *     NULL, if stroffset is out of bounds
 298 */
 299const char *fdt_string(const void *fdt, int stroffset);
 300
 301/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 302 * fdt_get_max_phandle - retrieves the highest phandle in a tree
 303 * @fdt: pointer to the device tree blob
 304 *
 305 * fdt_get_max_phandle retrieves the highest phandle in the given
 306 * device tree. This will ignore badly formatted phandles, or phandles
 307 * with a value of 0 or -1.
 308 *
 
 
 309 * returns:
 310 *      the highest phandle on success
 311 *      0, if no phandle was found in the device tree
 312 *      -1, if an error occurred
 313 */
 314uint32_t fdt_get_max_phandle(const void *fdt);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 315
 316/**
 317 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
 318 * @fdt: pointer to the device tree blob
 319 *
 320 * Returns the number of entries in the device tree blob's memory
 321 * reservation map.  This does not include the terminating 0,0 entry
 322 * or any other (0,0) entries reserved for expansion.
 323 *
 324 * returns:
 325 *     the number of entries
 326 */
 327int fdt_num_mem_rsv(const void *fdt);
 328
 329/**
 330 * fdt_get_mem_rsv - retrieve one memory reserve map entry
 331 * @fdt: pointer to the device tree blob
 332 * @address, @size: pointers to 64-bit variables
 333 *
 334 * On success, *address and *size will contain the address and size of
 335 * the n-th reserve map entry from the device tree blob, in
 336 * native-endian format.
 337 *
 338 * returns:
 339 *     0, on success
 340 *     -FDT_ERR_BADMAGIC,
 341 *     -FDT_ERR_BADVERSION,
 342 *     -FDT_ERR_BADSTATE, standard meanings
 343 */
 344int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
 345
 346/**
 347 * fdt_subnode_offset_namelen - find a subnode based on substring
 348 * @fdt: pointer to the device tree blob
 349 * @parentoffset: structure block offset of a node
 350 * @name: name of the subnode to locate
 351 * @namelen: number of characters of name to consider
 352 *
 353 * Identical to fdt_subnode_offset(), but only examine the first
 354 * namelen characters of name for matching the subnode name.  This is
 355 * useful for finding subnodes based on a portion of a larger string,
 356 * such as a full path.
 357 */
 358#ifndef SWIG /* Not available in Python */
 359int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
 360			       const char *name, int namelen);
 361#endif
 362/**
 363 * fdt_subnode_offset - find a subnode of a given node
 364 * @fdt: pointer to the device tree blob
 365 * @parentoffset: structure block offset of a node
 366 * @name: name of the subnode to locate
 367 *
 368 * fdt_subnode_offset() finds a subnode of the node at structure block
 369 * offset parentoffset with the given name.  name may include a unit
 370 * address, in which case fdt_subnode_offset() will find the subnode
 371 * with that unit address, or the unit address may be omitted, in
 372 * which case fdt_subnode_offset() will find an arbitrary subnode
 373 * whose name excluding unit address matches the given name.
 374 *
 375 * returns:
 376 *	structure block offset of the requested subnode (>=0), on success
 377 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
 378 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
 379 *		tag
 380 *	-FDT_ERR_BADMAGIC,
 381 *	-FDT_ERR_BADVERSION,
 382 *	-FDT_ERR_BADSTATE,
 383 *	-FDT_ERR_BADSTRUCTURE,
 384 *	-FDT_ERR_TRUNCATED, standard meanings.
 385 */
 386int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
 387
 388/**
 389 * fdt_path_offset_namelen - find a tree node by its full path
 390 * @fdt: pointer to the device tree blob
 391 * @path: full path of the node to locate
 392 * @namelen: number of characters of path to consider
 393 *
 394 * Identical to fdt_path_offset(), but only consider the first namelen
 395 * characters of path as the path name.
 396 */
 397#ifndef SWIG /* Not available in Python */
 398int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen);
 399#endif
 400
 401/**
 402 * fdt_path_offset - find a tree node by its full path
 403 * @fdt: pointer to the device tree blob
 404 * @path: full path of the node to locate
 405 *
 406 * fdt_path_offset() finds a node of a given path in the device tree.
 407 * Each path component may omit the unit address portion, but the
 408 * results of this are undefined if any such path component is
 409 * ambiguous (that is if there are multiple nodes at the relevant
 410 * level matching the given component, differentiated only by unit
 411 * address).
 412 *
 413 * returns:
 414 *	structure block offset of the node with the requested path (>=0), on
 415 *		success
 416 *	-FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
 417 *	-FDT_ERR_NOTFOUND, if the requested node does not exist
 418 *      -FDT_ERR_BADMAGIC,
 419 *	-FDT_ERR_BADVERSION,
 420 *	-FDT_ERR_BADSTATE,
 421 *	-FDT_ERR_BADSTRUCTURE,
 422 *	-FDT_ERR_TRUNCATED, standard meanings.
 423 */
 424int fdt_path_offset(const void *fdt, const char *path);
 425
 426/**
 427 * fdt_get_name - retrieve the name of a given node
 428 * @fdt: pointer to the device tree blob
 429 * @nodeoffset: structure block offset of the starting node
 430 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 431 *
 432 * fdt_get_name() retrieves the name (including unit address) of the
 433 * device tree node at structure block offset nodeoffset.  If lenp is
 434 * non-NULL, the length of this name is also returned, in the integer
 435 * pointed to by lenp.
 436 *
 437 * returns:
 438 *	pointer to the node's name, on success
 439 *		If lenp is non-NULL, *lenp contains the length of that name
 440 *			(>=0)
 441 *	NULL, on error
 442 *		if lenp is non-NULL *lenp contains an error code (<0):
 443 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
 444 *			tag
 445 *		-FDT_ERR_BADMAGIC,
 446 *		-FDT_ERR_BADVERSION,
 447 *		-FDT_ERR_BADSTATE, standard meanings
 448 */
 449const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
 450
 451/**
 452 * fdt_first_property_offset - find the offset of a node's first property
 453 * @fdt: pointer to the device tree blob
 454 * @nodeoffset: structure block offset of a node
 455 *
 456 * fdt_first_property_offset() finds the first property of the node at
 457 * the given structure block offset.
 458 *
 459 * returns:
 460 *	structure block offset of the property (>=0), on success
 461 *	-FDT_ERR_NOTFOUND, if the requested node has no properties
 462 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
 463 *      -FDT_ERR_BADMAGIC,
 464 *	-FDT_ERR_BADVERSION,
 465 *	-FDT_ERR_BADSTATE,
 466 *	-FDT_ERR_BADSTRUCTURE,
 467 *	-FDT_ERR_TRUNCATED, standard meanings.
 468 */
 469int fdt_first_property_offset(const void *fdt, int nodeoffset);
 470
 471/**
 472 * fdt_next_property_offset - step through a node's properties
 473 * @fdt: pointer to the device tree blob
 474 * @offset: structure block offset of a property
 475 *
 476 * fdt_next_property_offset() finds the property immediately after the
 477 * one at the given structure block offset.  This will be a property
 478 * of the same node as the given property.
 479 *
 480 * returns:
 481 *	structure block offset of the next property (>=0), on success
 482 *	-FDT_ERR_NOTFOUND, if the given property is the last in its node
 483 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag
 484 *      -FDT_ERR_BADMAGIC,
 485 *	-FDT_ERR_BADVERSION,
 486 *	-FDT_ERR_BADSTATE,
 487 *	-FDT_ERR_BADSTRUCTURE,
 488 *	-FDT_ERR_TRUNCATED, standard meanings.
 489 */
 490int fdt_next_property_offset(const void *fdt, int offset);
 491
 492/**
 493 * fdt_for_each_property_offset - iterate over all properties of a node
 494 *
 495 * @property_offset:	property offset (int, lvalue)
 496 * @fdt:		FDT blob (const void *)
 497 * @node:		node offset (int)
 498 *
 499 * This is actually a wrapper around a for loop and would be used like so:
 500 *
 501 *	fdt_for_each_property_offset(property, fdt, node) {
 502 *		Use property
 503 *		...
 504 *	}
 505 *
 506 *	if ((property < 0) && (property != -FDT_ERR_NOT_FOUND)) {
 507 *		Error handling
 508 *	}
 509 *
 510 * Note that this is implemented as a macro and property is used as
 511 * iterator in the loop. The node variable can be constant or even a
 512 * literal.
 513 */
 514#define fdt_for_each_property_offset(property, fdt, node)	\
 515	for (property = fdt_first_property_offset(fdt, node);	\
 516	     property >= 0;					\
 517	     property = fdt_next_property_offset(fdt, property))
 518
 519/**
 520 * fdt_get_property_by_offset - retrieve the property at a given offset
 521 * @fdt: pointer to the device tree blob
 522 * @offset: offset of the property to retrieve
 523 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 524 *
 525 * fdt_get_property_by_offset() retrieves a pointer to the
 526 * fdt_property structure within the device tree blob at the given
 527 * offset.  If lenp is non-NULL, the length of the property value is
 528 * also returned, in the integer pointed to by lenp.
 529 *
 530 * Note that this code only works on device tree versions >= 16. fdt_getprop()
 531 * works on all versions.
 532 *
 533 * returns:
 534 *	pointer to the structure representing the property
 535 *		if lenp is non-NULL, *lenp contains the length of the property
 536 *		value (>=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_PROP tag
 540 *		-FDT_ERR_BADMAGIC,
 541 *		-FDT_ERR_BADVERSION,
 542 *		-FDT_ERR_BADSTATE,
 543 *		-FDT_ERR_BADSTRUCTURE,
 544 *		-FDT_ERR_TRUNCATED, standard meanings
 545 */
 546const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
 547						      int offset,
 548						      int *lenp);
 549
 550/**
 551 * fdt_get_property_namelen - find a property based on substring
 552 * @fdt: pointer to the device tree blob
 553 * @nodeoffset: offset of the node whose property to find
 554 * @name: name of the property to find
 555 * @namelen: number of characters of name to consider
 556 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 557 *
 558 * Identical to fdt_get_property(), but only examine the first namelen
 559 * characters of name for matching the property name.
 560 */
 561#ifndef SWIG /* Not available in Python */
 562const struct fdt_property *fdt_get_property_namelen(const void *fdt,
 563						    int nodeoffset,
 564						    const char *name,
 565						    int namelen, int *lenp);
 566#endif
 567
 568/**
 569 * fdt_get_property - find a given property in a given node
 570 * @fdt: pointer to the device tree blob
 571 * @nodeoffset: offset of the node whose property to find
 572 * @name: name of the property to find
 573 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 574 *
 575 * fdt_get_property() retrieves a pointer to the fdt_property
 576 * structure within the device tree blob corresponding to the property
 577 * named 'name' of the node at offset nodeoffset.  If lenp is
 578 * non-NULL, the length of the property value is also returned, in the
 579 * integer pointed to by lenp.
 580 *
 581 * returns:
 582 *	pointer to the structure representing the property
 583 *		if lenp is non-NULL, *lenp contains the length of the property
 584 *		value (>=0)
 585 *	NULL, on error
 586 *		if lenp is non-NULL, *lenp contains an error code (<0):
 587 *		-FDT_ERR_NOTFOUND, node does not have named property
 588 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
 589 *			tag
 590 *		-FDT_ERR_BADMAGIC,
 591 *		-FDT_ERR_BADVERSION,
 592 *		-FDT_ERR_BADSTATE,
 593 *		-FDT_ERR_BADSTRUCTURE,
 594 *		-FDT_ERR_TRUNCATED, standard meanings
 595 */
 596const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
 597					    const char *name, int *lenp);
 598static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
 599						      const char *name,
 600						      int *lenp)
 601{
 602	return (struct fdt_property *)(uintptr_t)
 603		fdt_get_property(fdt, nodeoffset, name, lenp);
 604}
 605
 606/**
 607 * fdt_getprop_by_offset - retrieve the value of a property at a given offset
 608 * @fdt: pointer to the device tree blob
 609 * @ffset: offset of the property to read
 610 * @namep: pointer to a string variable (will be overwritten) or NULL
 611 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 612 *
 613 * fdt_getprop_by_offset() retrieves a pointer to the value of the
 614 * property at structure block offset 'offset' (this will be a pointer
 615 * to within the device blob itself, not a copy of the value).  If
 616 * lenp is non-NULL, the length of the property value is also
 617 * returned, in the integer pointed to by lenp.  If namep is non-NULL,
 618 * the property's namne will also be returned in the char * pointed to
 619 * by namep (this will be a pointer to within the device tree's string
 620 * block, not a new copy of the name).
 621 *
 622 * returns:
 623 *	pointer to the property's value
 624 *		if lenp is non-NULL, *lenp contains the length of the property
 625 *		value (>=0)
 626 *		if namep is non-NULL *namep contiains a pointer to the property
 627 *		name.
 628 *	NULL, on error
 629 *		if lenp is non-NULL, *lenp contains an error code (<0):
 630 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
 631 *		-FDT_ERR_BADMAGIC,
 632 *		-FDT_ERR_BADVERSION,
 633 *		-FDT_ERR_BADSTATE,
 634 *		-FDT_ERR_BADSTRUCTURE,
 635 *		-FDT_ERR_TRUNCATED, standard meanings
 636 */
 637#ifndef SWIG /* This function is not useful in Python */
 638const void *fdt_getprop_by_offset(const void *fdt, int offset,
 639				  const char **namep, int *lenp);
 640#endif
 641
 642/**
 643 * fdt_getprop_namelen - get property value based on substring
 644 * @fdt: pointer to the device tree blob
 645 * @nodeoffset: offset of the node whose property to find
 646 * @name: name of the property to find
 647 * @namelen: number of characters of name to consider
 648 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 649 *
 650 * Identical to fdt_getprop(), but only examine the first namelen
 651 * characters of name for matching the property name.
 652 */
 653#ifndef SWIG /* Not available in Python */
 654const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
 655				const char *name, int namelen, int *lenp);
 656static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset,
 657					  const char *name, int namelen,
 658					  int *lenp)
 659{
 660	return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name,
 661						      namelen, lenp);
 662}
 663#endif
 664
 665/**
 666 * fdt_getprop - retrieve the value of a given property
 667 * @fdt: pointer to the device tree blob
 668 * @nodeoffset: offset of the node whose property to find
 669 * @name: name of the property to find
 670 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 671 *
 672 * fdt_getprop() retrieves a pointer to the value of the property
 673 * named 'name' of the node at offset nodeoffset (this will be a
 674 * pointer to within the device blob itself, not a copy of the value).
 675 * If lenp is non-NULL, the length of the property value is also
 676 * returned, in the integer pointed to by lenp.
 677 *
 678 * returns:
 679 *	pointer to the property's value
 680 *		if lenp is non-NULL, *lenp contains the length of the property
 681 *		value (>=0)
 682 *	NULL, on error
 683 *		if lenp is non-NULL, *lenp contains an error code (<0):
 684 *		-FDT_ERR_NOTFOUND, node does not have named property
 685 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
 686 *			tag
 687 *		-FDT_ERR_BADMAGIC,
 688 *		-FDT_ERR_BADVERSION,
 689 *		-FDT_ERR_BADSTATE,
 690 *		-FDT_ERR_BADSTRUCTURE,
 691 *		-FDT_ERR_TRUNCATED, standard meanings
 692 */
 693const void *fdt_getprop(const void *fdt, int nodeoffset,
 694			const char *name, int *lenp);
 695static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
 696				  const char *name, int *lenp)
 697{
 698	return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
 699}
 700
 701/**
 702 * fdt_get_phandle - retrieve the phandle of a given node
 703 * @fdt: pointer to the device tree blob
 704 * @nodeoffset: structure block offset of the node
 705 *
 706 * fdt_get_phandle() retrieves the phandle of the device tree node at
 707 * structure block offset nodeoffset.
 708 *
 709 * returns:
 710 *	the phandle of the node at nodeoffset, on success (!= 0, != -1)
 711 *	0, if the node has no phandle, or another error occurs
 712 */
 713uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
 714
 715/**
 716 * fdt_get_alias_namelen - get alias based on substring
 717 * @fdt: pointer to the device tree blob
 718 * @name: name of the alias th look up
 719 * @namelen: number of characters of name to consider
 720 *
 721 * Identical to fdt_get_alias(), but only examine the first namelen
 722 * characters of name for matching the alias name.
 723 */
 724#ifndef SWIG /* Not available in Python */
 725const char *fdt_get_alias_namelen(const void *fdt,
 726				  const char *name, int namelen);
 727#endif
 728
 729/**
 730 * fdt_get_alias - retrieve the path referenced by a given alias
 731 * @fdt: pointer to the device tree blob
 732 * @name: name of the alias th look up
 733 *
 734 * fdt_get_alias() retrieves the value of a given alias.  That is, the
 735 * value of the property named 'name' in the node /aliases.
 736 *
 737 * returns:
 738 *	a pointer to the expansion of the alias named 'name', if it exists
 739 *	NULL, if the given alias or the /aliases node does not exist
 740 */
 741const char *fdt_get_alias(const void *fdt, const char *name);
 742
 743/**
 744 * fdt_get_path - determine the full path of a node
 745 * @fdt: pointer to the device tree blob
 746 * @nodeoffset: offset of the node whose path to find
 747 * @buf: character buffer to contain the returned path (will be overwritten)
 748 * @buflen: size of the character buffer at buf
 749 *
 750 * fdt_get_path() computes the full path of the node at offset
 751 * nodeoffset, and records that path in the buffer at buf.
 752 *
 753 * NOTE: This function is expensive, as it must scan the device tree
 754 * structure from the start to nodeoffset.
 755 *
 756 * returns:
 757 *	0, on success
 758 *		buf contains the absolute path of the node at
 759 *		nodeoffset, as a NUL-terminated string.
 760 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 761 *	-FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
 762 *		characters and will not fit in the given buffer.
 763 *	-FDT_ERR_BADMAGIC,
 764 *	-FDT_ERR_BADVERSION,
 765 *	-FDT_ERR_BADSTATE,
 766 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 767 */
 768int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
 769
 770/**
 771 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
 772 * @fdt: pointer to the device tree blob
 773 * @nodeoffset: offset of the node whose parent to find
 774 * @supernodedepth: depth of the ancestor to find
 775 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
 776 *
 777 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
 778 * at a specific depth from the root (where the root itself has depth
 779 * 0, its immediate subnodes depth 1 and so forth).  So
 780 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
 781 * will always return 0, the offset of the root node.  If the node at
 782 * nodeoffset has depth D, then:
 783 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
 784 * will return nodeoffset itself.
 785 *
 786 * NOTE: This function is expensive, as it must scan the device tree
 787 * structure from the start to nodeoffset.
 788 *
 789 * returns:
 790 *	structure block offset of the node at node offset's ancestor
 791 *		of depth supernodedepth (>=0), on success
 792 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 793 *	-FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of
 794 *		nodeoffset
 795 *	-FDT_ERR_BADMAGIC,
 796 *	-FDT_ERR_BADVERSION,
 797 *	-FDT_ERR_BADSTATE,
 798 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 799 */
 800int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
 801				 int supernodedepth, int *nodedepth);
 802
 803/**
 804 * fdt_node_depth - find the depth of a given node
 805 * @fdt: pointer to the device tree blob
 806 * @nodeoffset: offset of the node whose parent to find
 807 *
 808 * fdt_node_depth() finds the depth of a given node.  The root node
 809 * has depth 0, its immediate subnodes depth 1 and so forth.
 810 *
 811 * NOTE: This function is expensive, as it must scan the device tree
 812 * structure from the start to nodeoffset.
 813 *
 814 * returns:
 815 *	depth of the node at nodeoffset (>=0), on success
 816 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 817 *	-FDT_ERR_BADMAGIC,
 818 *	-FDT_ERR_BADVERSION,
 819 *	-FDT_ERR_BADSTATE,
 820 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 821 */
 822int fdt_node_depth(const void *fdt, int nodeoffset);
 823
 824/**
 825 * fdt_parent_offset - find the parent of a given node
 826 * @fdt: pointer to the device tree blob
 827 * @nodeoffset: offset of the node whose parent to find
 828 *
 829 * fdt_parent_offset() locates the parent node of a given node (that
 830 * is, it finds the offset of the node which contains the node at
 831 * nodeoffset as a subnode).
 832 *
 833 * NOTE: This function is expensive, as it must scan the device tree
 834 * structure from the start to nodeoffset, *twice*.
 835 *
 836 * returns:
 837 *	structure block offset of the parent of the node at nodeoffset
 838 *		(>=0), on success
 839 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 840 *	-FDT_ERR_BADMAGIC,
 841 *	-FDT_ERR_BADVERSION,
 842 *	-FDT_ERR_BADSTATE,
 843 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 844 */
 845int fdt_parent_offset(const void *fdt, int nodeoffset);
 846
 847/**
 848 * fdt_node_offset_by_prop_value - find nodes with a given property value
 849 * @fdt: pointer to the device tree blob
 850 * @startoffset: only find nodes after this offset
 851 * @propname: property name to check
 852 * @propval: property value to search for
 853 * @proplen: length of the value in propval
 854 *
 855 * fdt_node_offset_by_prop_value() returns the offset of the first
 856 * node after startoffset, which has a property named propname whose
 857 * value is of length proplen and has value equal to propval; or if
 858 * startoffset is -1, the very first such node in the tree.
 859 *
 860 * To iterate through all nodes matching the criterion, the following
 861 * idiom can be used:
 862 *	offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
 863 *					       propval, proplen);
 864 *	while (offset != -FDT_ERR_NOTFOUND) {
 865 *		// other code here
 866 *		offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
 867 *						       propval, proplen);
 868 *	}
 869 *
 870 * Note the -1 in the first call to the function, if 0 is used here
 871 * instead, the function will never locate the root node, even if it
 872 * matches the criterion.
 873 *
 874 * returns:
 875 *	structure block offset of the located node (>= 0, >startoffset),
 876 *		 on success
 877 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
 878 *		tree after startoffset
 879 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 880 *	-FDT_ERR_BADMAGIC,
 881 *	-FDT_ERR_BADVERSION,
 882 *	-FDT_ERR_BADSTATE,
 883 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 884 */
 885int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
 886				  const char *propname,
 887				  const void *propval, int proplen);
 888
 889/**
 890 * fdt_node_offset_by_phandle - find the node with a given phandle
 891 * @fdt: pointer to the device tree blob
 892 * @phandle: phandle value
 893 *
 894 * fdt_node_offset_by_phandle() returns the offset of the node
 895 * which has the given phandle value.  If there is more than one node
 896 * in the tree with the given phandle (an invalid tree), results are
 897 * undefined.
 898 *
 899 * returns:
 900 *	structure block offset of the located node (>= 0), on success
 901 *	-FDT_ERR_NOTFOUND, no node with that phandle exists
 902 *	-FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
 903 *	-FDT_ERR_BADMAGIC,
 904 *	-FDT_ERR_BADVERSION,
 905 *	-FDT_ERR_BADSTATE,
 906 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 907 */
 908int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
 909
 910/**
 911 * fdt_node_check_compatible: check a node's compatible property
 912 * @fdt: pointer to the device tree blob
 913 * @nodeoffset: offset of a tree node
 914 * @compatible: string to match against
 915 *
 916 *
 917 * fdt_node_check_compatible() returns 0 if the given node contains a
 918 * 'compatible' property with the given string as one of its elements,
 919 * it returns non-zero otherwise, or on error.
 920 *
 921 * returns:
 922 *	0, if the node has a 'compatible' property listing the given string
 923 *	1, if the node has a 'compatible' property, but it does not list
 924 *		the given string
 925 *	-FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
 926 *	-FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
 927 *	-FDT_ERR_BADMAGIC,
 928 *	-FDT_ERR_BADVERSION,
 929 *	-FDT_ERR_BADSTATE,
 930 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 931 */
 932int fdt_node_check_compatible(const void *fdt, int nodeoffset,
 933			      const char *compatible);
 934
 935/**
 936 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
 937 * @fdt: pointer to the device tree blob
 938 * @startoffset: only find nodes after this offset
 939 * @compatible: 'compatible' string to match against
 940 *
 941 * fdt_node_offset_by_compatible() returns the offset of the first
 942 * node after startoffset, which has a 'compatible' property which
 943 * lists the given compatible string; or if startoffset is -1, the
 944 * very first such node in the tree.
 945 *
 946 * To iterate through all nodes matching the criterion, the following
 947 * idiom can be used:
 948 *	offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
 949 *	while (offset != -FDT_ERR_NOTFOUND) {
 950 *		// other code here
 951 *		offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
 952 *	}
 953 *
 954 * Note the -1 in the first call to the function, if 0 is used here
 955 * instead, the function will never locate the root node, even if it
 956 * matches the criterion.
 957 *
 958 * returns:
 959 *	structure block offset of the located node (>= 0, >startoffset),
 960 *		 on success
 961 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
 962 *		tree after startoffset
 963 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 964 *	-FDT_ERR_BADMAGIC,
 965 *	-FDT_ERR_BADVERSION,
 966 *	-FDT_ERR_BADSTATE,
 967 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 968 */
 969int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
 970				  const char *compatible);
 971
 972/**
 973 * fdt_stringlist_contains - check a string list property for a string
 974 * @strlist: Property containing a list of strings to check
 975 * @listlen: Length of property
 976 * @str: String to search for
 977 *
 978 * This is a utility function provided for convenience. The list contains
 979 * one or more strings, each terminated by \0, as is found in a device tree
 980 * "compatible" property.
 981 *
 982 * @return: 1 if the string is found in the list, 0 not found, or invalid list
 983 */
 984int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
 985
 986/**
 987 * fdt_stringlist_count - count the number of strings in a string list
 988 * @fdt: pointer to the device tree blob
 989 * @nodeoffset: offset of a tree node
 990 * @property: name of the property containing the string list
 991 * @return:
 992 *   the number of strings in the given property
 993 *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
 994 *   -FDT_ERR_NOTFOUND if the property does not exist
 995 */
 996int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property);
 997
 998/**
 999 * fdt_stringlist_search - find a string in a string list and return its index
1000 * @fdt: pointer to the device tree blob
1001 * @nodeoffset: offset of a tree node
1002 * @property: name of the property containing the string list
1003 * @string: string to look up in the string list
1004 *
1005 * Note that it is possible for this function to succeed on property values
1006 * that are not NUL-terminated. That's because the function will stop after
1007 * finding the first occurrence of @string. This can for example happen with
1008 * small-valued cell properties, such as #address-cells, when searching for
1009 * the empty string.
1010 *
1011 * @return:
1012 *   the index of the string in the list of strings
1013 *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1014 *   -FDT_ERR_NOTFOUND if the property does not exist or does not contain
1015 *                     the given string
1016 */
1017int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
1018			  const char *string);
1019
1020/**
1021 * fdt_stringlist_get() - obtain the string at a given index in a string list
1022 * @fdt: pointer to the device tree blob
1023 * @nodeoffset: offset of a tree node
1024 * @property: name of the property containing the string list
1025 * @index: index of the string to return
1026 * @lenp: return location for the string length or an error code on failure
1027 *
1028 * Note that this will successfully extract strings from properties with
1029 * non-NUL-terminated values. For example on small-valued cell properties
1030 * this function will return the empty string.
1031 *
1032 * If non-NULL, the length of the string (on success) or a negative error-code
1033 * (on failure) will be stored in the integer pointer to by lenp.
1034 *
1035 * @return:
1036 *   A pointer to the string at the given index in the string list or NULL on
1037 *   failure. On success the length of the string will be stored in the memory
1038 *   location pointed to by the lenp parameter, if non-NULL. On failure one of
1039 *   the following negative error codes will be returned in the lenp parameter
1040 *   (if non-NULL):
1041 *     -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1042 *     -FDT_ERR_NOTFOUND if the property does not exist
1043 */
1044const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
1045			       const char *property, int index,
1046			       int *lenp);
1047
1048/**********************************************************************/
1049/* Read-only functions (addressing related)                           */
1050/**********************************************************************/
1051
1052/**
1053 * FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells
1054 *
1055 * This is the maximum value for #address-cells, #size-cells and
1056 * similar properties that will be processed by libfdt.  IEE1275
1057 * requires that OF implementations handle values up to 4.
1058 * Implementations may support larger values, but in practice higher
1059 * values aren't used.
1060 */
1061#define FDT_MAX_NCELLS		4
1062
1063/**
1064 * fdt_address_cells - retrieve address size for a bus represented in the tree
1065 * @fdt: pointer to the device tree blob
1066 * @nodeoffset: offset of the node to find the address size for
1067 *
1068 * When the node has a valid #address-cells property, returns its value.
1069 *
1070 * returns:
1071 *	0 <= n < FDT_MAX_NCELLS, on success
1072 *      2, if the node has no #address-cells property
1073 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1074 *		#address-cells property
1075 *	-FDT_ERR_BADMAGIC,
1076 *	-FDT_ERR_BADVERSION,
1077 *	-FDT_ERR_BADSTATE,
1078 *	-FDT_ERR_BADSTRUCTURE,
1079 *	-FDT_ERR_TRUNCATED, standard meanings
1080 */
1081int fdt_address_cells(const void *fdt, int nodeoffset);
1082
1083/**
1084 * fdt_size_cells - retrieve address range size for a bus represented in the
1085 *                  tree
1086 * @fdt: pointer to the device tree blob
1087 * @nodeoffset: offset of the node to find the address range size for
1088 *
1089 * When the node has a valid #size-cells property, returns its value.
1090 *
1091 * returns:
1092 *	0 <= n < FDT_MAX_NCELLS, on success
1093 *      2, if the node has no #address-cells property
1094 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1095 *		#size-cells property
1096 *	-FDT_ERR_BADMAGIC,
1097 *	-FDT_ERR_BADVERSION,
1098 *	-FDT_ERR_BADSTATE,
1099 *	-FDT_ERR_BADSTRUCTURE,
1100 *	-FDT_ERR_TRUNCATED, standard meanings
1101 */
1102int fdt_size_cells(const void *fdt, int nodeoffset);
1103
1104
1105/**********************************************************************/
1106/* Write-in-place functions                                           */
1107/**********************************************************************/
1108
1109/**
1110 * fdt_setprop_inplace_namelen_partial - change a property's value,
1111 *                                       but not its size
1112 * @fdt: pointer to the device tree blob
1113 * @nodeoffset: offset of the node whose property to change
1114 * @name: name of the property to change
1115 * @namelen: number of characters of name to consider
1116 * @idx: index of the property to change in the array
1117 * @val: pointer to data to replace the property value with
1118 * @len: length of the property value
1119 *
1120 * Identical to fdt_setprop_inplace(), but modifies the given property
1121 * starting from the given index, and using only the first characters
1122 * of the name. It is useful when you want to manipulate only one value of
1123 * an array and you have a string that doesn't end with \0.
1124 */
1125#ifndef SWIG /* Not available in Python */
1126int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
1127					const char *name, int namelen,
1128					uint32_t idx, const void *val,
1129					int len);
1130#endif
1131
1132/**
1133 * fdt_setprop_inplace - change a property's value, but not its size
1134 * @fdt: pointer to the device tree blob
1135 * @nodeoffset: offset of the node whose property to change
1136 * @name: name of the property to change
1137 * @val: pointer to data to replace the property value with
1138 * @len: length of the property value
1139 *
1140 * fdt_setprop_inplace() replaces the value of a given property with
1141 * the data in val, of length len.  This function cannot change the
1142 * size of a property, and so will only work if len is equal to the
1143 * current length of the property.
1144 *
1145 * This function will alter only the bytes in the blob which contain
1146 * the given property value, and will not alter or move any other part
1147 * of the tree.
1148 *
1149 * returns:
1150 *	0, on success
1151 *	-FDT_ERR_NOSPACE, if len is not equal to the property's current length
1152 *	-FDT_ERR_NOTFOUND, node does not have the named property
1153 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1154 *	-FDT_ERR_BADMAGIC,
1155 *	-FDT_ERR_BADVERSION,
1156 *	-FDT_ERR_BADSTATE,
1157 *	-FDT_ERR_BADSTRUCTURE,
1158 *	-FDT_ERR_TRUNCATED, standard meanings
1159 */
1160#ifndef SWIG /* Not available in Python */
1161int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
1162			const void *val, int len);
1163#endif
1164
1165/**
1166 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
1167 * @fdt: pointer to the device tree blob
1168 * @nodeoffset: offset of the node whose property to change
1169 * @name: name of the property to change
1170 * @val: 32-bit integer value to replace the property with
1171 *
1172 * fdt_setprop_inplace_u32() replaces the value of a given property
1173 * with the 32-bit integer value in val, converting val to big-endian
1174 * if necessary.  This function cannot change the size of a property,
1175 * and so will only work if the property already exists and has length
1176 * 4.
1177 *
1178 * This function will alter only the bytes in the blob which contain
1179 * the given property value, and will not alter or move any other part
1180 * of the tree.
1181 *
1182 * returns:
1183 *	0, on success
1184 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 4
1185 *	-FDT_ERR_NOTFOUND, node does not have the named property
1186 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1187 *	-FDT_ERR_BADMAGIC,
1188 *	-FDT_ERR_BADVERSION,
1189 *	-FDT_ERR_BADSTATE,
1190 *	-FDT_ERR_BADSTRUCTURE,
1191 *	-FDT_ERR_TRUNCATED, standard meanings
1192 */
1193static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
1194					  const char *name, uint32_t val)
1195{
1196	fdt32_t tmp = cpu_to_fdt32(val);
1197	return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1198}
1199
1200/**
1201 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
1202 * @fdt: pointer to the device tree blob
1203 * @nodeoffset: offset of the node whose property to change
1204 * @name: name of the property to change
1205 * @val: 64-bit integer value to replace the property with
1206 *
1207 * fdt_setprop_inplace_u64() replaces the value of a given property
1208 * with the 64-bit integer value in val, converting val to big-endian
1209 * if necessary.  This function cannot change the size of a property,
1210 * and so will only work if the property already exists and has length
1211 * 8.
1212 *
1213 * This function will alter only the bytes in the blob which contain
1214 * the given property value, and will not alter or move any other part
1215 * of the tree.
1216 *
1217 * returns:
1218 *	0, on success
1219 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 8
1220 *	-FDT_ERR_NOTFOUND, node does not have the named property
1221 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1222 *	-FDT_ERR_BADMAGIC,
1223 *	-FDT_ERR_BADVERSION,
1224 *	-FDT_ERR_BADSTATE,
1225 *	-FDT_ERR_BADSTRUCTURE,
1226 *	-FDT_ERR_TRUNCATED, standard meanings
1227 */
1228static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
1229					  const char *name, uint64_t val)
1230{
1231	fdt64_t tmp = cpu_to_fdt64(val);
1232	return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1233}
1234
1235/**
1236 * fdt_setprop_inplace_cell - change the value of a single-cell property
1237 *
1238 * This is an alternative name for fdt_setprop_inplace_u32()
1239 */
1240static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
1241					   const char *name, uint32_t val)
1242{
1243	return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
1244}
1245
1246/**
1247 * fdt_nop_property - replace a property with nop tags
1248 * @fdt: pointer to the device tree blob
1249 * @nodeoffset: offset of the node whose property to nop
1250 * @name: name of the property to nop
1251 *
1252 * fdt_nop_property() will replace a given property's representation
1253 * in the blob with FDT_NOP tags, effectively removing it from the
1254 * tree.
1255 *
1256 * This function will alter only the bytes in the blob which contain
1257 * the property, and will not alter or move any other part of the
1258 * tree.
1259 *
1260 * returns:
1261 *	0, on success
1262 *	-FDT_ERR_NOTFOUND, node does not have the named property
1263 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1264 *	-FDT_ERR_BADMAGIC,
1265 *	-FDT_ERR_BADVERSION,
1266 *	-FDT_ERR_BADSTATE,
1267 *	-FDT_ERR_BADSTRUCTURE,
1268 *	-FDT_ERR_TRUNCATED, standard meanings
1269 */
1270int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
1271
1272/**
1273 * fdt_nop_node - replace a node (subtree) with nop tags
1274 * @fdt: pointer to the device tree blob
1275 * @nodeoffset: offset of the node to nop
1276 *
1277 * fdt_nop_node() will replace a given node's representation in the
1278 * blob, including all its subnodes, if any, with FDT_NOP tags,
1279 * effectively removing it from the tree.
1280 *
1281 * This function will alter only the bytes in the blob which contain
1282 * the node and its properties and subnodes, and will not alter or
1283 * move any other part of the tree.
1284 *
1285 * returns:
1286 *	0, on success
1287 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1288 *	-FDT_ERR_BADMAGIC,
1289 *	-FDT_ERR_BADVERSION,
1290 *	-FDT_ERR_BADSTATE,
1291 *	-FDT_ERR_BADSTRUCTURE,
1292 *	-FDT_ERR_TRUNCATED, standard meanings
1293 */
1294int fdt_nop_node(void *fdt, int nodeoffset);
1295
1296/**********************************************************************/
1297/* Sequential write functions                                         */
1298/**********************************************************************/
1299
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1300int fdt_create(void *buf, int bufsize);
 
1301int fdt_resize(void *fdt, void *buf, int bufsize);
1302int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
1303int fdt_finish_reservemap(void *fdt);
1304int fdt_begin_node(void *fdt, const char *name);
1305int fdt_property(void *fdt, const char *name, const void *val, int len);
1306static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
1307{
1308	fdt32_t tmp = cpu_to_fdt32(val);
1309	return fdt_property(fdt, name, &tmp, sizeof(tmp));
1310}
1311static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
1312{
1313	fdt64_t tmp = cpu_to_fdt64(val);
1314	return fdt_property(fdt, name, &tmp, sizeof(tmp));
1315}
 
 
1316static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
1317{
1318	return fdt_property_u32(fdt, name, val);
1319}
 
1320
1321/**
1322 * fdt_property_placeholder - add a new property and return a ptr to its value
1323 *
1324 * @fdt: pointer to the device tree blob
1325 * @name: name of property to add
1326 * @len: length of property value in bytes
1327 * @valp: returns a pointer to where where the value should be placed
1328 *
1329 * returns:
1330 *	0, on success
1331 *	-FDT_ERR_BADMAGIC,
1332 *	-FDT_ERR_NOSPACE, standard meanings
1333 */
1334int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp);
1335
1336#define fdt_property_string(fdt, name, str) \
1337	fdt_property(fdt, name, str, strlen(str)+1)
1338int fdt_end_node(void *fdt);
1339int fdt_finish(void *fdt);
1340
1341/**********************************************************************/
1342/* Read-write functions                                               */
1343/**********************************************************************/
1344
1345int fdt_create_empty_tree(void *buf, int bufsize);
1346int fdt_open_into(const void *fdt, void *buf, int bufsize);
1347int fdt_pack(void *fdt);
1348
1349/**
1350 * fdt_add_mem_rsv - add one memory reserve map entry
1351 * @fdt: pointer to the device tree blob
1352 * @address, @size: 64-bit values (native endian)
1353 *
1354 * Adds a reserve map entry to the given blob reserving a region at
1355 * address address of length size.
1356 *
1357 * This function will insert data into the reserve map and will
1358 * therefore change the indexes of some entries in the table.
1359 *
1360 * returns:
1361 *	0, on success
1362 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1363 *		contain the new reservation entry
1364 *	-FDT_ERR_BADMAGIC,
1365 *	-FDT_ERR_BADVERSION,
1366 *	-FDT_ERR_BADSTATE,
1367 *	-FDT_ERR_BADSTRUCTURE,
1368 *	-FDT_ERR_BADLAYOUT,
1369 *	-FDT_ERR_TRUNCATED, standard meanings
1370 */
1371int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
1372
1373/**
1374 * fdt_del_mem_rsv - remove a memory reserve map entry
1375 * @fdt: pointer to the device tree blob
1376 * @n: entry to remove
1377 *
1378 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
1379 * the blob.
1380 *
1381 * This function will delete data from the reservation table and will
1382 * therefore change the indexes of some entries in the table.
1383 *
1384 * returns:
1385 *	0, on success
1386 *	-FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
1387 *		are less than n+1 reserve map entries)
1388 *	-FDT_ERR_BADMAGIC,
1389 *	-FDT_ERR_BADVERSION,
1390 *	-FDT_ERR_BADSTATE,
1391 *	-FDT_ERR_BADSTRUCTURE,
1392 *	-FDT_ERR_BADLAYOUT,
1393 *	-FDT_ERR_TRUNCATED, standard meanings
1394 */
1395int fdt_del_mem_rsv(void *fdt, int n);
1396
1397/**
1398 * fdt_set_name - change the name of a given node
1399 * @fdt: pointer to the device tree blob
1400 * @nodeoffset: structure block offset of a node
1401 * @name: name to give the node
1402 *
1403 * fdt_set_name() replaces the name (including unit address, if any)
1404 * of the given node with the given string.  NOTE: this function can't
1405 * efficiently check if the new name is unique amongst the given
1406 * node's siblings; results are undefined if this function is invoked
1407 * with a name equal to one of the given node's siblings.
1408 *
1409 * This function may insert or delete data from the blob, and will
1410 * therefore change the offsets of some existing nodes.
1411 *
1412 * returns:
1413 *	0, on success
1414 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob
1415 *		to contain the new name
1416 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1417 *	-FDT_ERR_BADMAGIC,
1418 *	-FDT_ERR_BADVERSION,
1419 *	-FDT_ERR_BADSTATE, standard meanings
1420 */
1421int fdt_set_name(void *fdt, int nodeoffset, const char *name);
1422
1423/**
1424 * fdt_setprop - create or change a property
1425 * @fdt: pointer to the device tree blob
1426 * @nodeoffset: offset of the node whose property to change
1427 * @name: name of the property to change
1428 * @val: pointer to data to set the property value to
1429 * @len: length of the property value
1430 *
1431 * fdt_setprop() sets the value of the named property in the given
1432 * node to the given value and length, creating the property if it
1433 * does not already exist.
1434 *
1435 * This function may insert or delete data from the blob, and will
1436 * therefore change the offsets of some existing nodes.
1437 *
1438 * returns:
1439 *	0, on success
1440 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1441 *		contain the new property value
1442 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1443 *	-FDT_ERR_BADLAYOUT,
1444 *	-FDT_ERR_BADMAGIC,
1445 *	-FDT_ERR_BADVERSION,
1446 *	-FDT_ERR_BADSTATE,
1447 *	-FDT_ERR_BADSTRUCTURE,
1448 *	-FDT_ERR_BADLAYOUT,
1449 *	-FDT_ERR_TRUNCATED, standard meanings
1450 */
1451int fdt_setprop(void *fdt, int nodeoffset, const char *name,
1452		const void *val, int len);
1453
1454/**
1455 * fdt_setprop_placeholder - allocate space for a property
1456 * @fdt: pointer to the device tree blob
1457 * @nodeoffset: offset of the node whose property to change
1458 * @name: name of the property to change
1459 * @len: length of the property value
1460 * @prop_data: return pointer to property data
1461 *
1462 * fdt_setprop_placeholer() allocates the named property in the given node.
1463 * If the property exists it is resized. In either case a pointer to the
1464 * property data is returned.
1465 *
1466 * This function may insert or delete data from the blob, and will
1467 * therefore change the offsets of some existing nodes.
1468 *
1469 * returns:
1470 *	0, on success
1471 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1472 *		contain the new property value
1473 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1474 *	-FDT_ERR_BADLAYOUT,
1475 *	-FDT_ERR_BADMAGIC,
1476 *	-FDT_ERR_BADVERSION,
1477 *	-FDT_ERR_BADSTATE,
1478 *	-FDT_ERR_BADSTRUCTURE,
1479 *	-FDT_ERR_BADLAYOUT,
1480 *	-FDT_ERR_TRUNCATED, standard meanings
1481 */
1482int fdt_setprop_placeholder(void *fdt, int nodeoffset, const char *name,
1483			    int len, void **prop_data);
1484
1485/**
1486 * fdt_setprop_u32 - set a property to a 32-bit integer
1487 * @fdt: pointer to the device tree blob
1488 * @nodeoffset: offset of the node whose property to change
1489 * @name: name of the property to change
1490 * @val: 32-bit integer value for the property (native endian)
1491 *
1492 * fdt_setprop_u32() sets the value of the named property in the given
1493 * node to the given 32-bit integer value (converting to big-endian if
1494 * necessary), or creates a new property with that value if it does
1495 * not already exist.
1496 *
1497 * This function may insert or delete data from the blob, and will
1498 * therefore change the offsets of some existing nodes.
1499 *
1500 * returns:
1501 *	0, on success
1502 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1503 *		contain the new property value
1504 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1505 *	-FDT_ERR_BADLAYOUT,
1506 *	-FDT_ERR_BADMAGIC,
1507 *	-FDT_ERR_BADVERSION,
1508 *	-FDT_ERR_BADSTATE,
1509 *	-FDT_ERR_BADSTRUCTURE,
1510 *	-FDT_ERR_BADLAYOUT,
1511 *	-FDT_ERR_TRUNCATED, standard meanings
1512 */
1513static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
1514				  uint32_t val)
1515{
1516	fdt32_t tmp = cpu_to_fdt32(val);
1517	return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1518}
1519
1520/**
1521 * fdt_setprop_u64 - set a property to a 64-bit integer
1522 * @fdt: pointer to the device tree blob
1523 * @nodeoffset: offset of the node whose property to change
1524 * @name: name of the property to change
1525 * @val: 64-bit integer value for the property (native endian)
1526 *
1527 * fdt_setprop_u64() sets the value of the named property in the given
1528 * node to the given 64-bit integer value (converting to big-endian if
1529 * necessary), or creates a new property with that value if it does
1530 * not already exist.
1531 *
1532 * This function may insert or delete data from the blob, and will
1533 * therefore change the offsets of some existing nodes.
1534 *
1535 * returns:
1536 *	0, on success
1537 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1538 *		contain the new property value
1539 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1540 *	-FDT_ERR_BADLAYOUT,
1541 *	-FDT_ERR_BADMAGIC,
1542 *	-FDT_ERR_BADVERSION,
1543 *	-FDT_ERR_BADSTATE,
1544 *	-FDT_ERR_BADSTRUCTURE,
1545 *	-FDT_ERR_BADLAYOUT,
1546 *	-FDT_ERR_TRUNCATED, standard meanings
1547 */
1548static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
1549				  uint64_t val)
1550{
1551	fdt64_t tmp = cpu_to_fdt64(val);
1552	return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1553}
1554
1555/**
1556 * fdt_setprop_cell - set a property to a single cell value
1557 *
1558 * This is an alternative name for fdt_setprop_u32()
1559 */
1560static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
1561				   uint32_t val)
1562{
1563	return fdt_setprop_u32(fdt, nodeoffset, name, val);
1564}
1565
1566/**
1567 * fdt_setprop_string - set a property to a string value
1568 * @fdt: pointer to the device tree blob
1569 * @nodeoffset: offset of the node whose property to change
1570 * @name: name of the property to change
1571 * @str: string value for the property
1572 *
1573 * fdt_setprop_string() sets the value of the named property in the
1574 * given node to the given string value (using the length of the
1575 * string to determine the new length of the property), or creates a
1576 * new property with that value if it does not already exist.
1577 *
1578 * This function may insert or delete data from the blob, and will
1579 * therefore change the offsets of some existing nodes.
1580 *
1581 * returns:
1582 *	0, on success
1583 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1584 *		contain the new property value
1585 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1586 *	-FDT_ERR_BADLAYOUT,
1587 *	-FDT_ERR_BADMAGIC,
1588 *	-FDT_ERR_BADVERSION,
1589 *	-FDT_ERR_BADSTATE,
1590 *	-FDT_ERR_BADSTRUCTURE,
1591 *	-FDT_ERR_BADLAYOUT,
1592 *	-FDT_ERR_TRUNCATED, standard meanings
1593 */
1594#define fdt_setprop_string(fdt, nodeoffset, name, str) \
1595	fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1596
1597
1598/**
1599 * fdt_setprop_empty - set a property to an empty value
1600 * @fdt: pointer to the device tree blob
1601 * @nodeoffset: offset of the node whose property to change
1602 * @name: name of the property to change
1603 *
1604 * fdt_setprop_empty() sets the value of the named property in the
1605 * given node to an empty (zero length) value, or creates a new empty
1606 * property if it does not already exist.
1607 *
1608 * This function may insert or delete data from the blob, and will
1609 * therefore change the offsets of some existing nodes.
1610 *
1611 * returns:
1612 *	0, on success
1613 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1614 *		contain the new property value
1615 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1616 *	-FDT_ERR_BADLAYOUT,
1617 *	-FDT_ERR_BADMAGIC,
1618 *	-FDT_ERR_BADVERSION,
1619 *	-FDT_ERR_BADSTATE,
1620 *	-FDT_ERR_BADSTRUCTURE,
1621 *	-FDT_ERR_BADLAYOUT,
1622 *	-FDT_ERR_TRUNCATED, standard meanings
1623 */
1624#define fdt_setprop_empty(fdt, nodeoffset, name) \
1625	fdt_setprop((fdt), (nodeoffset), (name), NULL, 0)
1626
1627/**
1628 * fdt_appendprop - append to or create a property
1629 * @fdt: pointer to the device tree blob
1630 * @nodeoffset: offset of the node whose property to change
1631 * @name: name of the property to append to
1632 * @val: pointer to data to append to the property value
1633 * @len: length of the data to append to the property value
1634 *
1635 * fdt_appendprop() appends the value to the named property in the
1636 * given node, creating the property if it does not already exist.
1637 *
1638 * This function may insert data into the blob, and will therefore
1639 * change the offsets of some existing nodes.
1640 *
1641 * returns:
1642 *	0, on success
1643 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1644 *		contain the new property value
1645 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1646 *	-FDT_ERR_BADLAYOUT,
1647 *	-FDT_ERR_BADMAGIC,
1648 *	-FDT_ERR_BADVERSION,
1649 *	-FDT_ERR_BADSTATE,
1650 *	-FDT_ERR_BADSTRUCTURE,
1651 *	-FDT_ERR_BADLAYOUT,
1652 *	-FDT_ERR_TRUNCATED, standard meanings
1653 */
1654int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
1655		   const void *val, int len);
1656
1657/**
1658 * fdt_appendprop_u32 - append a 32-bit integer value to a property
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: 32-bit integer value to append to the property (native endian)
1663 *
1664 * fdt_appendprop_u32() appends the given 32-bit integer value
1665 * (converting to big-endian if necessary) to the value of the named
1666 * property in the given node, or creates a new property with that
1667 * value if it does not already exist.
1668 *
1669 * This function may insert data into the blob, and will therefore
1670 * 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_appendprop_u32(void *fdt, int nodeoffset,
1686				     const char *name, uint32_t val)
1687{
1688	fdt32_t tmp = cpu_to_fdt32(val);
1689	return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1690}
1691
1692/**
1693 * fdt_appendprop_u64 - append a 64-bit integer value to a property
1694 * @fdt: pointer to the device tree blob
1695 * @nodeoffset: offset of the node whose property to change
1696 * @name: name of the property to change
1697 * @val: 64-bit integer value to append to the property (native endian)
1698 *
1699 * fdt_appendprop_u64() appends the given 64-bit integer value
1700 * (converting to big-endian if necessary) to the value of the named
1701 * property in the given node, or creates a new property with that
1702 * value if it does not already exist.
1703 *
1704 * This function may insert data into the blob, and will therefore
1705 * change the offsets of some existing nodes.
1706 *
1707 * returns:
1708 *	0, on success
1709 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1710 *		contain the new property value
1711 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1712 *	-FDT_ERR_BADLAYOUT,
1713 *	-FDT_ERR_BADMAGIC,
1714 *	-FDT_ERR_BADVERSION,
1715 *	-FDT_ERR_BADSTATE,
1716 *	-FDT_ERR_BADSTRUCTURE,
1717 *	-FDT_ERR_BADLAYOUT,
1718 *	-FDT_ERR_TRUNCATED, standard meanings
1719 */
1720static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
1721				     const char *name, uint64_t val)
1722{
1723	fdt64_t tmp = cpu_to_fdt64(val);
1724	return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1725}
1726
1727/**
1728 * fdt_appendprop_cell - append a single cell value to a property
1729 *
1730 * This is an alternative name for fdt_appendprop_u32()
1731 */
1732static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
1733				      const char *name, uint32_t val)
1734{
1735	return fdt_appendprop_u32(fdt, nodeoffset, name, val);
1736}
1737
1738/**
1739 * fdt_appendprop_string - append a string to a property
1740 * @fdt: pointer to the device tree blob
1741 * @nodeoffset: offset of the node whose property to change
1742 * @name: name of the property to change
1743 * @str: string value to append to the property
1744 *
1745 * fdt_appendprop_string() appends the given string to the value of
1746 * the named property in the given node, or creates a new property
1747 * with that value if it does not already exist.
1748 *
1749 * This function may insert data into the blob, and will therefore
1750 * change the offsets of some existing nodes.
1751 *
1752 * returns:
1753 *	0, on success
1754 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1755 *		contain the new property value
1756 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1757 *	-FDT_ERR_BADLAYOUT,
1758 *	-FDT_ERR_BADMAGIC,
1759 *	-FDT_ERR_BADVERSION,
1760 *	-FDT_ERR_BADSTATE,
1761 *	-FDT_ERR_BADSTRUCTURE,
1762 *	-FDT_ERR_BADLAYOUT,
1763 *	-FDT_ERR_TRUNCATED, standard meanings
1764 */
1765#define fdt_appendprop_string(fdt, nodeoffset, name, str) \
1766	fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1767
1768/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1769 * fdt_delprop - delete a property
1770 * @fdt: pointer to the device tree blob
1771 * @nodeoffset: offset of the node whose property to nop
1772 * @name: name of the property to nop
1773 *
1774 * fdt_del_property() will delete the given property.
1775 *
1776 * This function will delete data from the blob, and will therefore
1777 * change the offsets of some existing nodes.
1778 *
1779 * returns:
1780 *	0, on success
1781 *	-FDT_ERR_NOTFOUND, node does not have the named property
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_TRUNCATED, standard meanings
1789 */
1790int fdt_delprop(void *fdt, int nodeoffset, const char *name);
1791
1792/**
1793 * fdt_add_subnode_namelen - creates a new node based on substring
1794 * @fdt: pointer to the device tree blob
1795 * @parentoffset: structure block offset of a node
1796 * @name: name of the subnode to locate
1797 * @namelen: number of characters of name to consider
1798 *
1799 * Identical to fdt_add_subnode(), but use only the first namelen
1800 * characters of name as the name of the new node.  This is useful for
1801 * creating subnodes based on a portion of a larger string, such as a
1802 * full path.
1803 */
1804#ifndef SWIG /* Not available in Python */
1805int fdt_add_subnode_namelen(void *fdt, int parentoffset,
1806			    const char *name, int namelen);
1807#endif
1808
1809/**
1810 * fdt_add_subnode - creates a new node
1811 * @fdt: pointer to the device tree blob
1812 * @parentoffset: structure block offset of a node
1813 * @name: name of the subnode to locate
1814 *
1815 * fdt_add_subnode() creates a new node as a subnode of the node at
1816 * structure block offset parentoffset, with the given name (which
1817 * should include the unit address, if any).
1818 *
1819 * This function will insert data into the blob, and will therefore
1820 * change the offsets of some existing nodes.
1821
1822 * returns:
1823 *	structure block offset of the created nodeequested subnode (>=0), on
1824 *		success
1825 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
1826 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
1827 *		tag
1828 *	-FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
1829 *		the given name
1830 *	-FDT_ERR_NOSPACE, if there is insufficient free space in the
1831 *		blob to contain the new node
1832 *	-FDT_ERR_NOSPACE
1833 *	-FDT_ERR_BADLAYOUT
1834 *      -FDT_ERR_BADMAGIC,
1835 *	-FDT_ERR_BADVERSION,
1836 *	-FDT_ERR_BADSTATE,
1837 *	-FDT_ERR_BADSTRUCTURE,
1838 *	-FDT_ERR_TRUNCATED, standard meanings.
1839 */
1840int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
1841
1842/**
1843 * fdt_del_node - delete a node (subtree)
1844 * @fdt: pointer to the device tree blob
1845 * @nodeoffset: offset of the node to nop
1846 *
1847 * fdt_del_node() will remove the given node, including all its
1848 * subnodes if any, from the blob.
1849 *
1850 * This function will delete data from the blob, and will therefore
1851 * change the offsets of some existing nodes.
1852 *
1853 * returns:
1854 *	0, on success
1855 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1856 *	-FDT_ERR_BADLAYOUT,
1857 *	-FDT_ERR_BADMAGIC,
1858 *	-FDT_ERR_BADVERSION,
1859 *	-FDT_ERR_BADSTATE,
1860 *	-FDT_ERR_BADSTRUCTURE,
1861 *	-FDT_ERR_TRUNCATED, standard meanings
1862 */
1863int fdt_del_node(void *fdt, int nodeoffset);
1864
1865/**
1866 * fdt_overlay_apply - Applies a DT overlay on a base DT
1867 * @fdt: pointer to the base device tree blob
1868 * @fdto: pointer to the device tree overlay blob
1869 *
1870 * fdt_overlay_apply() will apply the given device tree overlay on the
1871 * given base device tree.
1872 *
1873 * Expect the base device tree to be modified, even if the function
1874 * returns an error.
1875 *
1876 * returns:
1877 *	0, on success
1878 *	-FDT_ERR_NOSPACE, there's not enough space in the base device tree
1879 *	-FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
1880 *		properties in the base DT
1881 *	-FDT_ERR_BADPHANDLE,
1882 *	-FDT_ERR_BADOVERLAY,
1883 *	-FDT_ERR_NOPHANDLES,
1884 *	-FDT_ERR_INTERNAL,
1885 *	-FDT_ERR_BADLAYOUT,
1886 *	-FDT_ERR_BADMAGIC,
1887 *	-FDT_ERR_BADOFFSET,
1888 *	-FDT_ERR_BADPATH,
1889 *	-FDT_ERR_BADVERSION,
1890 *	-FDT_ERR_BADSTRUCTURE,
1891 *	-FDT_ERR_BADSTATE,
1892 *	-FDT_ERR_TRUNCATED, standard meanings
1893 */
1894int fdt_overlay_apply(void *fdt, void *fdto);
1895
1896/**********************************************************************/
1897/* Debugging / informational functions                                */
1898/**********************************************************************/
1899
1900const char *fdt_strerror(int errval);
 
 
 
 
1901
1902#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 */