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v3.5.6
   1#ifndef _LIBFDT_H
   2#define _LIBFDT_H
   3/*
   4 * libfdt - Flat Device Tree manipulation
   5 * Copyright (C) 2006 David Gibson, IBM Corporation.
   6 *
   7 * libfdt is dual licensed: you can use it either under the terms of
   8 * the GPL, or the BSD license, at your option.
   9 *
  10 *  a) This library is free software; you can redistribute it and/or
  11 *     modify it under the terms of the GNU General Public License as
  12 *     published by the Free Software Foundation; either version 2 of the
  13 *     License, or (at your option) any later version.
  14 *
  15 *     This library is distributed in the hope that it will be useful,
  16 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 *     GNU General Public License for more details.
  19 *
  20 *     You should have received a copy of the GNU General Public
  21 *     License along with this library; if not, write to the Free
  22 *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  23 *     MA 02110-1301 USA
  24 *
  25 * Alternatively,
  26 *
  27 *  b) Redistribution and use in source and binary forms, with or
  28 *     without modification, are permitted provided that the following
  29 *     conditions are met:
  30 *
  31 *     1. Redistributions of source code must retain the above
  32 *        copyright notice, this list of conditions and the following
  33 *        disclaimer.
  34 *     2. Redistributions in binary form must reproduce the above
  35 *        copyright notice, this list of conditions and the following
  36 *        disclaimer in the documentation and/or other materials
  37 *        provided with the distribution.
  38 *
  39 *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  40 *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  41 *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  42 *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  43 *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  44 *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45 *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46 *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47 *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48 *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  49 *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  50 *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
  51 *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  52 */
  53
  54#include <libfdt_env.h>
  55#include <fdt.h>
  56
  57#define FDT_FIRST_SUPPORTED_VERSION	0x10
  58#define FDT_LAST_SUPPORTED_VERSION	0x11
  59
  60/* Error codes: informative error codes */
  61#define FDT_ERR_NOTFOUND	1
  62	/* FDT_ERR_NOTFOUND: The requested node or property does not exist */
  63#define FDT_ERR_EXISTS		2
  64	/* FDT_ERR_EXISTS: Attempted to create a node or property which
  65	 * already exists */
  66#define FDT_ERR_NOSPACE		3
  67	/* FDT_ERR_NOSPACE: Operation needed to expand the device
  68	 * tree, but its buffer did not have sufficient space to
  69	 * contain the expanded tree. Use fdt_open_into() to move the
  70	 * device tree to a buffer with more space. */
  71
  72/* Error codes: codes for bad parameters */
  73#define FDT_ERR_BADOFFSET	4
  74	/* FDT_ERR_BADOFFSET: Function was passed a structure block
  75	 * offset which is out-of-bounds, or which points to an
  76	 * unsuitable part of the structure for the operation. */
  77#define FDT_ERR_BADPATH		5
  78	/* FDT_ERR_BADPATH: Function was passed a badly formatted path
  79	 * (e.g. missing a leading / for a function which requires an
  80	 * absolute path) */
  81#define FDT_ERR_BADPHANDLE	6
  82	/* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle
  83	 * value.  phandle values of 0 and -1 are not permitted. */
  84#define FDT_ERR_BADSTATE	7
  85	/* FDT_ERR_BADSTATE: Function was passed an incomplete device
  86	 * tree created by the sequential-write functions, which is
  87	 * not sufficiently complete for the requested operation. */
  88
  89/* Error codes: codes for bad device tree blobs */
  90#define FDT_ERR_TRUNCATED	8
  91	/* FDT_ERR_TRUNCATED: Structure block of the given device tree
  92	 * ends without an FDT_END tag. */
  93#define FDT_ERR_BADMAGIC	9
  94	/* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
  95	 * device tree at all - it is missing the flattened device
  96	 * tree magic number. */
  97#define FDT_ERR_BADVERSION	10
  98	/* FDT_ERR_BADVERSION: Given device tree has a version which
  99	 * can't be handled by the requested operation.  For
 100	 * read-write functions, this may mean that fdt_open_into() is
 101	 * required to convert the tree to the expected version. */
 102#define FDT_ERR_BADSTRUCTURE	11
 103	/* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt
 104	 * structure block or other serious error (e.g. misnested
 105	 * nodes, or subnodes preceding properties). */
 106#define FDT_ERR_BADLAYOUT	12
 107	/* FDT_ERR_BADLAYOUT: For read-write functions, the given
 108	 * device tree has it's sub-blocks in an order that the
 109	 * function can't handle (memory reserve map, then structure,
 110	 * then strings).  Use fdt_open_into() to reorganize the tree
 111	 * into a form suitable for the read-write operations. */
 112
 113/* "Can't happen" error indicating a bug in libfdt */
 114#define FDT_ERR_INTERNAL	13
 115	/* FDT_ERR_INTERNAL: libfdt has failed an internal assertion.
 116	 * Should never be returned, if it is, it indicates a bug in
 117	 * libfdt itself. */
 118
 119#define FDT_ERR_MAX		13
 120
 121/**********************************************************************/
 122/* Low-level functions (you probably don't need these)                */
 123/**********************************************************************/
 124
 125const void *fdt_offset_ptr(const void *fdt, int offset, int checklen);
 126static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
 127{
 128	return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
 129}
 130
 131uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
 132
 133/**********************************************************************/
 134/* Traversal functions                                                */
 135/**********************************************************************/
 136
 137int fdt_next_node(const void *fdt, int offset, int *depth);
 138
 139/**********************************************************************/
 140/* General functions                                                  */
 141/**********************************************************************/
 142
 143#define fdt_get_header(fdt, field) \
 144	(fdt32_to_cpu(((const struct fdt_header *)(fdt))->field))
 145#define fdt_magic(fdt) 			(fdt_get_header(fdt, magic))
 146#define fdt_totalsize(fdt)		(fdt_get_header(fdt, totalsize))
 147#define fdt_off_dt_struct(fdt)		(fdt_get_header(fdt, off_dt_struct))
 148#define fdt_off_dt_strings(fdt)		(fdt_get_header(fdt, off_dt_strings))
 149#define fdt_off_mem_rsvmap(fdt)		(fdt_get_header(fdt, off_mem_rsvmap))
 150#define fdt_version(fdt)		(fdt_get_header(fdt, version))
 151#define fdt_last_comp_version(fdt) 	(fdt_get_header(fdt, last_comp_version))
 152#define fdt_boot_cpuid_phys(fdt) 	(fdt_get_header(fdt, boot_cpuid_phys))
 153#define fdt_size_dt_strings(fdt) 	(fdt_get_header(fdt, size_dt_strings))
 154#define fdt_size_dt_struct(fdt)		(fdt_get_header(fdt, size_dt_struct))
 155
 156#define __fdt_set_hdr(name) \
 157	static inline void fdt_set_##name(void *fdt, uint32_t val) \
 158	{ \
 159		struct fdt_header *fdth = fdt; \
 160		fdth->name = cpu_to_fdt32(val); \
 161	}
 162__fdt_set_hdr(magic);
 163__fdt_set_hdr(totalsize);
 164__fdt_set_hdr(off_dt_struct);
 165__fdt_set_hdr(off_dt_strings);
 166__fdt_set_hdr(off_mem_rsvmap);
 167__fdt_set_hdr(version);
 168__fdt_set_hdr(last_comp_version);
 169__fdt_set_hdr(boot_cpuid_phys);
 170__fdt_set_hdr(size_dt_strings);
 171__fdt_set_hdr(size_dt_struct);
 172#undef __fdt_set_hdr
 173
 174/**
 175 * fdt_check_header - sanity check a device tree or possible device tree
 176 * @fdt: pointer to data which might be a flattened device tree
 177 *
 178 * fdt_check_header() checks that the given buffer contains what
 179 * appears to be a flattened device tree with sane information in its
 180 * header.
 181 *
 182 * returns:
 183 *     0, if the buffer appears to contain a valid device tree
 184 *     -FDT_ERR_BADMAGIC,
 185 *     -FDT_ERR_BADVERSION,
 186 *     -FDT_ERR_BADSTATE, standard meanings, as above
 187 */
 188int fdt_check_header(const void *fdt);
 189
 190/**
 191 * fdt_move - move a device tree around in memory
 192 * @fdt: pointer to the device tree to move
 193 * @buf: pointer to memory where the device is to be moved
 194 * @bufsize: size of the memory space at buf
 195 *
 196 * fdt_move() relocates, if possible, the device tree blob located at
 197 * fdt to the buffer at buf of size bufsize.  The buffer may overlap
 198 * with the existing device tree blob at fdt.  Therefore,
 199 *     fdt_move(fdt, fdt, fdt_totalsize(fdt))
 200 * should always succeed.
 201 *
 202 * returns:
 203 *     0, on success
 204 *     -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
 205 *     -FDT_ERR_BADMAGIC,
 206 *     -FDT_ERR_BADVERSION,
 207 *     -FDT_ERR_BADSTATE, standard meanings
 208 */
 209int fdt_move(const void *fdt, void *buf, int bufsize);
 210
 211/**********************************************************************/
 212/* Read-only functions                                                */
 213/**********************************************************************/
 214
 215/**
 216 * fdt_string - retrieve a string from the strings block of a device tree
 217 * @fdt: pointer to the device tree blob
 218 * @stroffset: offset of the string within the strings block (native endian)
 219 *
 220 * fdt_string() retrieves a pointer to a single string from the
 221 * strings block of the device tree blob at fdt.
 222 *
 223 * returns:
 224 *     a pointer to the string, on success
 225 *     NULL, if stroffset is out of bounds
 226 */
 227const char *fdt_string(const void *fdt, int stroffset);
 228
 229/**
 230 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
 231 * @fdt: pointer to the device tree blob
 232 *
 233 * Returns the number of entries in the device tree blob's memory
 234 * reservation map.  This does not include the terminating 0,0 entry
 235 * or any other (0,0) entries reserved for expansion.
 236 *
 237 * returns:
 238 *     the number of entries
 239 */
 240int fdt_num_mem_rsv(const void *fdt);
 241
 242/**
 243 * fdt_get_mem_rsv - retrieve one memory reserve map entry
 244 * @fdt: pointer to the device tree blob
 245 * @address, @size: pointers to 64-bit variables
 246 *
 247 * On success, *address and *size will contain the address and size of
 248 * the n-th reserve map entry from the device tree blob, in
 249 * native-endian format.
 250 *
 251 * returns:
 252 *     0, on success
 253 *     -FDT_ERR_BADMAGIC,
 254 *     -FDT_ERR_BADVERSION,
 255 *     -FDT_ERR_BADSTATE, standard meanings
 256 */
 257int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
 258
 259/**
 260 * fdt_subnode_offset_namelen - find a subnode based on substring
 261 * @fdt: pointer to the device tree blob
 262 * @parentoffset: structure block offset of a node
 263 * @name: name of the subnode to locate
 264 * @namelen: number of characters of name to consider
 265 *
 266 * Identical to fdt_subnode_offset(), but only examine the first
 267 * namelen characters of name for matching the subnode name.  This is
 268 * useful for finding subnodes based on a portion of a larger string,
 269 * such as a full path.
 270 */
 271int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
 272			       const char *name, int namelen);
 273/**
 274 * fdt_subnode_offset - find a subnode of a given node
 275 * @fdt: pointer to the device tree blob
 276 * @parentoffset: structure block offset of a node
 277 * @name: name of the subnode to locate
 278 *
 279 * fdt_subnode_offset() finds a subnode of the node at structure block
 280 * offset parentoffset with the given name.  name may include a unit
 281 * address, in which case fdt_subnode_offset() will find the subnode
 282 * with that unit address, or the unit address may be omitted, in
 283 * which case fdt_subnode_offset() will find an arbitrary subnode
 284 * whose name excluding unit address matches the given name.
 285 *
 286 * returns:
 287 *	structure block offset of the requested subnode (>=0), on success
 288 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
 289 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
 290 *      -FDT_ERR_BADMAGIC,
 291 *	-FDT_ERR_BADVERSION,
 292 *	-FDT_ERR_BADSTATE,
 293 *	-FDT_ERR_BADSTRUCTURE,
 294 *	-FDT_ERR_TRUNCATED, standard meanings.
 295 */
 296int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
 297
 298/**
 299 * fdt_path_offset - find a tree node by its full path
 300 * @fdt: pointer to the device tree blob
 301 * @path: full path of the node to locate
 302 *
 303 * fdt_path_offset() finds a node of a given path in the device tree.
 304 * Each path component may omit the unit address portion, but the
 305 * results of this are undefined if any such path component is
 306 * ambiguous (that is if there are multiple nodes at the relevant
 307 * level matching the given component, differentiated only by unit
 308 * address).
 309 *
 310 * returns:
 311 *	structure block offset of the node with the requested path (>=0), on success
 312 *	-FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
 313 *	-FDT_ERR_NOTFOUND, if the requested node does not exist
 314 *      -FDT_ERR_BADMAGIC,
 315 *	-FDT_ERR_BADVERSION,
 316 *	-FDT_ERR_BADSTATE,
 317 *	-FDT_ERR_BADSTRUCTURE,
 318 *	-FDT_ERR_TRUNCATED, standard meanings.
 319 */
 320int fdt_path_offset(const void *fdt, const char *path);
 321
 322/**
 323 * fdt_get_name - retrieve the name of a given node
 324 * @fdt: pointer to the device tree blob
 325 * @nodeoffset: structure block offset of the starting node
 326 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 327 *
 328 * fdt_get_name() retrieves the name (including unit address) of the
 329 * device tree node at structure block offset nodeoffset.  If lenp is
 330 * non-NULL, the length of this name is also returned, in the integer
 331 * pointed to by lenp.
 332 *
 333 * returns:
 334 *	pointer to the node's name, on success
 335 *		If lenp is non-NULL, *lenp contains the length of that name (>=0)
 336 *	NULL, on error
 337 *		if lenp is non-NULL *lenp contains an error code (<0):
 338 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 339 *		-FDT_ERR_BADMAGIC,
 340 *		-FDT_ERR_BADVERSION,
 341 *		-FDT_ERR_BADSTATE, standard meanings
 342 */
 343const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
 344
 345/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 346 * fdt_get_property - find a given property in a given node
 347 * @fdt: pointer to the device tree blob
 348 * @nodeoffset: offset of the node whose property to find
 349 * @name: name of the property to find
 350 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 351 *
 352 * fdt_get_property() retrieves a pointer to the fdt_property
 353 * structure within the device tree blob corresponding to the property
 354 * named 'name' of the node at offset nodeoffset.  If lenp is
 355 * non-NULL, the length of the property value is also returned, in the
 356 * integer pointed to by lenp.
 357 *
 358 * returns:
 359 *	pointer to the structure representing the property
 360 *		if lenp is non-NULL, *lenp contains the length of the property
 361 *		value (>=0)
 362 *	NULL, on error
 363 *		if lenp is non-NULL, *lenp contains an error code (<0):
 364 *		-FDT_ERR_NOTFOUND, node does not have named property
 365 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 366 *		-FDT_ERR_BADMAGIC,
 367 *		-FDT_ERR_BADVERSION,
 368 *		-FDT_ERR_BADSTATE,
 369 *		-FDT_ERR_BADSTRUCTURE,
 370 *		-FDT_ERR_TRUNCATED, standard meanings
 371 */
 372const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
 373					    const char *name, int *lenp);
 374static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
 375						      const char *name,
 376						      int *lenp)
 377{
 378	return (struct fdt_property *)(uintptr_t)
 379		fdt_get_property(fdt, nodeoffset, name, lenp);
 380}
 381
 382/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 383 * fdt_getprop - retrieve the value of a given property
 384 * @fdt: pointer to the device tree blob
 385 * @nodeoffset: offset of the node whose property to find
 386 * @name: name of the property to find
 387 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 388 *
 389 * fdt_getprop() retrieves a pointer to the value of the property
 390 * named 'name' of the node at offset nodeoffset (this will be a
 391 * pointer to within the device blob itself, not a copy of the value).
 392 * If lenp is non-NULL, the length of the property value is also
 393 * returned, in the integer pointed to by lenp.
 394 *
 395 * returns:
 396 *	pointer to the property's value
 397 *		if lenp is non-NULL, *lenp contains the length of the property
 398 *		value (>=0)
 399 *	NULL, on error
 400 *		if lenp is non-NULL, *lenp contains an error code (<0):
 401 *		-FDT_ERR_NOTFOUND, node does not have named property
 402 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 403 *		-FDT_ERR_BADMAGIC,
 404 *		-FDT_ERR_BADVERSION,
 405 *		-FDT_ERR_BADSTATE,
 406 *		-FDT_ERR_BADSTRUCTURE,
 407 *		-FDT_ERR_TRUNCATED, standard meanings
 408 */
 409const void *fdt_getprop(const void *fdt, int nodeoffset,
 410			const char *name, int *lenp);
 411static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
 412				  const char *name, int *lenp)
 413{
 414	return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
 415}
 416
 417/**
 418 * fdt_get_phandle - retrieve the phandle of a given node
 419 * @fdt: pointer to the device tree blob
 420 * @nodeoffset: structure block offset of the node
 421 *
 422 * fdt_get_phandle() retrieves the phandle of the device tree node at
 423 * structure block offset nodeoffset.
 424 *
 425 * returns:
 426 *	the phandle of the node at nodeoffset, on success (!= 0, != -1)
 427 *	0, if the node has no phandle, or another error occurs
 428 */
 429uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
 430
 431/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 432 * fdt_get_path - determine the full path of a node
 433 * @fdt: pointer to the device tree blob
 434 * @nodeoffset: offset of the node whose path to find
 435 * @buf: character buffer to contain the returned path (will be overwritten)
 436 * @buflen: size of the character buffer at buf
 437 *
 438 * fdt_get_path() computes the full path of the node at offset
 439 * nodeoffset, and records that path in the buffer at buf.
 440 *
 441 * NOTE: This function is expensive, as it must scan the device tree
 442 * structure from the start to nodeoffset.
 443 *
 444 * returns:
 445 *	0, on success
 446 *		buf contains the absolute path of the node at
 447 *		nodeoffset, as a NUL-terminated string.
 448 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 449 *	-FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
 450 *		characters and will not fit in the given buffer.
 451 *	-FDT_ERR_BADMAGIC,
 452 *	-FDT_ERR_BADVERSION,
 453 *	-FDT_ERR_BADSTATE,
 454 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 455 */
 456int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
 457
 458/**
 459 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
 460 * @fdt: pointer to the device tree blob
 461 * @nodeoffset: offset of the node whose parent to find
 462 * @supernodedepth: depth of the ancestor to find
 463 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
 464 *
 465 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
 466 * at a specific depth from the root (where the root itself has depth
 467 * 0, its immediate subnodes depth 1 and so forth).  So
 468 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
 469 * will always return 0, the offset of the root node.  If the node at
 470 * nodeoffset has depth D, then:
 471 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
 472 * will return nodeoffset itself.
 473 *
 474 * NOTE: This function is expensive, as it must scan the device tree
 475 * structure from the start to nodeoffset.
 476 *
 477 * returns:
 478
 479 *	structure block offset of the node at node offset's ancestor
 480 *		of depth supernodedepth (>=0), on success
 481 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 482*	-FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of nodeoffset
 483 *	-FDT_ERR_BADMAGIC,
 484 *	-FDT_ERR_BADVERSION,
 485 *	-FDT_ERR_BADSTATE,
 486 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 487 */
 488int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
 489				 int supernodedepth, int *nodedepth);
 490
 491/**
 492 * fdt_node_depth - find the depth of a given node
 493 * @fdt: pointer to the device tree blob
 494 * @nodeoffset: offset of the node whose parent to find
 495 *
 496 * fdt_node_depth() finds the depth of a given node.  The root node
 497 * has depth 0, its immediate subnodes depth 1 and so forth.
 498 *
 499 * NOTE: This function is expensive, as it must scan the device tree
 500 * structure from the start to nodeoffset.
 501 *
 502 * returns:
 503 *	depth of the node at nodeoffset (>=0), on success
 504 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 505 *	-FDT_ERR_BADMAGIC,
 506 *	-FDT_ERR_BADVERSION,
 507 *	-FDT_ERR_BADSTATE,
 508 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 509 */
 510int fdt_node_depth(const void *fdt, int nodeoffset);
 511
 512/**
 513 * fdt_parent_offset - find the parent of a given node
 514 * @fdt: pointer to the device tree blob
 515 * @nodeoffset: offset of the node whose parent to find
 516 *
 517 * fdt_parent_offset() locates the parent node of a given node (that
 518 * is, it finds the offset of the node which contains the node at
 519 * nodeoffset as a subnode).
 520 *
 521 * NOTE: This function is expensive, as it must scan the device tree
 522 * structure from the start to nodeoffset, *twice*.
 523 *
 524 * returns:
 525 *	structure block offset of the parent of the node at nodeoffset
 526 *		(>=0), on success
 527 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 528 *	-FDT_ERR_BADMAGIC,
 529 *	-FDT_ERR_BADVERSION,
 530 *	-FDT_ERR_BADSTATE,
 531 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 532 */
 533int fdt_parent_offset(const void *fdt, int nodeoffset);
 534
 535/**
 536 * fdt_node_offset_by_prop_value - find nodes with a given property value
 537 * @fdt: pointer to the device tree blob
 538 * @startoffset: only find nodes after this offset
 539 * @propname: property name to check
 540 * @propval: property value to search for
 541 * @proplen: length of the value in propval
 542 *
 543 * fdt_node_offset_by_prop_value() returns the offset of the first
 544 * node after startoffset, which has a property named propname whose
 545 * value is of length proplen and has value equal to propval; or if
 546 * startoffset is -1, the very first such node in the tree.
 547 *
 548 * To iterate through all nodes matching the criterion, the following
 549 * idiom can be used:
 550 *	offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
 551 *					       propval, proplen);
 552 *	while (offset != -FDT_ERR_NOTFOUND) {
 553 *		// other code here
 554 *		offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
 555 *						       propval, proplen);
 556 *	}
 557 *
 558 * Note the -1 in the first call to the function, if 0 is used here
 559 * instead, the function will never locate the root node, even if it
 560 * matches the criterion.
 561 *
 562 * returns:
 563 *	structure block offset of the located node (>= 0, >startoffset),
 564 *		 on success
 565 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
 566 *		tree after startoffset
 567 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 568 *	-FDT_ERR_BADMAGIC,
 569 *	-FDT_ERR_BADVERSION,
 570 *	-FDT_ERR_BADSTATE,
 571 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 572 */
 573int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
 574				  const char *propname,
 575				  const void *propval, int proplen);
 576
 577/**
 578 * fdt_node_offset_by_phandle - find the node with a given phandle
 579 * @fdt: pointer to the device tree blob
 580 * @phandle: phandle value
 581 *
 582 * fdt_node_offset_by_phandle() returns the offset of the node
 583 * which has the given phandle value.  If there is more than one node
 584 * in the tree with the given phandle (an invalid tree), results are
 585 * undefined.
 586 *
 587 * returns:
 588 *	structure block offset of the located node (>= 0), on success
 589 *	-FDT_ERR_NOTFOUND, no node with that phandle exists
 590 *	-FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
 591 *	-FDT_ERR_BADMAGIC,
 592 *	-FDT_ERR_BADVERSION,
 593 *	-FDT_ERR_BADSTATE,
 594 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 595 */
 596int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
 597
 598/**
 599 * fdt_node_check_compatible: check a node's compatible property
 600 * @fdt: pointer to the device tree blob
 601 * @nodeoffset: offset of a tree node
 602 * @compatible: string to match against
 603 *
 604 *
 605 * fdt_node_check_compatible() returns 0 if the given node contains a
 606 * 'compatible' property with the given string as one of its elements,
 607 * it returns non-zero otherwise, or on error.
 608 *
 609 * returns:
 610 *	0, if the node has a 'compatible' property listing the given string
 611 *	1, if the node has a 'compatible' property, but it does not list
 612 *		the given string
 613 *	-FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
 614 * 	-FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
 615 *	-FDT_ERR_BADMAGIC,
 616 *	-FDT_ERR_BADVERSION,
 617 *	-FDT_ERR_BADSTATE,
 618 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 619 */
 620int fdt_node_check_compatible(const void *fdt, int nodeoffset,
 621			      const char *compatible);
 622
 623/**
 624 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
 625 * @fdt: pointer to the device tree blob
 626 * @startoffset: only find nodes after this offset
 627 * @compatible: 'compatible' string to match against
 628 *
 629 * fdt_node_offset_by_compatible() returns the offset of the first
 630 * node after startoffset, which has a 'compatible' property which
 631 * lists the given compatible string; or if startoffset is -1, the
 632 * very first such node in the tree.
 633 *
 634 * To iterate through all nodes matching the criterion, the following
 635 * idiom can be used:
 636 *	offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
 637 *	while (offset != -FDT_ERR_NOTFOUND) {
 638 *		// other code here
 639 *		offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
 640 *	}
 641 *
 642 * Note the -1 in the first call to the function, if 0 is used here
 643 * instead, the function will never locate the root node, even if it
 644 * matches the criterion.
 645 *
 646 * returns:
 647 *	structure block offset of the located node (>= 0, >startoffset),
 648 *		 on success
 649 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
 650 *		tree after startoffset
 651 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 652 *	-FDT_ERR_BADMAGIC,
 653 *	-FDT_ERR_BADVERSION,
 654 *	-FDT_ERR_BADSTATE,
 655 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 656 */
 657int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
 658				  const char *compatible);
 659
 660/**********************************************************************/
 661/* Write-in-place functions                                           */
 662/**********************************************************************/
 663
 664/**
 665 * fdt_setprop_inplace - change a property's value, but not its size
 666 * @fdt: pointer to the device tree blob
 667 * @nodeoffset: offset of the node whose property to change
 668 * @name: name of the property to change
 669 * @val: pointer to data to replace the property value with
 670 * @len: length of the property value
 671 *
 672 * fdt_setprop_inplace() replaces the value of a given property with
 673 * the data in val, of length len.  This function cannot change the
 674 * size of a property, and so will only work if len is equal to the
 675 * current length of the property.
 676 *
 677 * This function will alter only the bytes in the blob which contain
 678 * the given property value, and will not alter or move any other part
 679 * of the tree.
 680 *
 681 * returns:
 682 *	0, on success
 683 *	-FDT_ERR_NOSPACE, if len is not equal to the property's current length
 684 *	-FDT_ERR_NOTFOUND, node does not have the named property
 685 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 686 *	-FDT_ERR_BADMAGIC,
 687 *	-FDT_ERR_BADVERSION,
 688 *	-FDT_ERR_BADSTATE,
 689 *	-FDT_ERR_BADSTRUCTURE,
 690 *	-FDT_ERR_TRUNCATED, standard meanings
 691 */
 692int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
 693			const void *val, int len);
 694
 695/**
 696 * fdt_setprop_inplace_cell - change the value of a single-cell property
 697 * @fdt: pointer to the device tree blob
 698 * @nodeoffset: offset of the node whose property to change
 699 * @name: name of the property to change
 700 * @val: cell (32-bit integer) value to replace the property with
 701 *
 702 * fdt_setprop_inplace_cell() replaces the value of a given property
 703 * with the 32-bit integer cell value in val, converting val to
 704 * big-endian if necessary.  This function cannot change the size of a
 705 * property, and so will only work if the property already exists and
 706 * has length 4.
 707 *
 708 * This function will alter only the bytes in the blob which contain
 709 * the given property value, and will not alter or move any other part
 710 * of the tree.
 711 *
 712 * returns:
 713 *	0, on success
 714 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 4
 715  *	-FDT_ERR_NOTFOUND, node does not have the named property
 716 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 717 *	-FDT_ERR_BADMAGIC,
 718 *	-FDT_ERR_BADVERSION,
 719 *	-FDT_ERR_BADSTATE,
 720 *	-FDT_ERR_BADSTRUCTURE,
 721 *	-FDT_ERR_TRUNCATED, standard meanings
 722 */
 723static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
 724					   const char *name, uint32_t val)
 725{
 726	val = cpu_to_fdt32(val);
 727	return fdt_setprop_inplace(fdt, nodeoffset, name, &val, sizeof(val));
 728}
 729
 730/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 731 * fdt_nop_property - replace a property with nop tags
 732 * @fdt: pointer to the device tree blob
 733 * @nodeoffset: offset of the node whose property to nop
 734 * @name: name of the property to nop
 735 *
 736 * fdt_nop_property() will replace a given property's representation
 737 * in the blob with FDT_NOP tags, effectively removing it from the
 738 * tree.
 739 *
 740 * This function will alter only the bytes in the blob which contain
 741 * the property, and will not alter or move any other part of the
 742 * tree.
 743 *
 744 * returns:
 745 *	0, on success
 746 *	-FDT_ERR_NOTFOUND, node does not have the named property
 747 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 748 *	-FDT_ERR_BADMAGIC,
 749 *	-FDT_ERR_BADVERSION,
 750 *	-FDT_ERR_BADSTATE,
 751 *	-FDT_ERR_BADSTRUCTURE,
 752 *	-FDT_ERR_TRUNCATED, standard meanings
 753 */
 754int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
 755
 756/**
 757 * fdt_nop_node - replace a node (subtree) with nop tags
 758 * @fdt: pointer to the device tree blob
 759 * @nodeoffset: offset of the node to nop
 760 *
 761 * fdt_nop_node() will replace a given node's representation in the
 762 * blob, including all its subnodes, if any, with FDT_NOP tags,
 763 * effectively removing it from the tree.
 764 *
 765 * This function will alter only the bytes in the blob which contain
 766 * the node and its properties and subnodes, and will not alter or
 767 * move any other part of the tree.
 768 *
 769 * returns:
 770 *	0, on success
 771 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 772 *	-FDT_ERR_BADMAGIC,
 773 *	-FDT_ERR_BADVERSION,
 774 *	-FDT_ERR_BADSTATE,
 775 *	-FDT_ERR_BADSTRUCTURE,
 776 *	-FDT_ERR_TRUNCATED, standard meanings
 777 */
 778int fdt_nop_node(void *fdt, int nodeoffset);
 779
 780/**********************************************************************/
 781/* Sequential write functions                                         */
 782/**********************************************************************/
 783
 784int fdt_create(void *buf, int bufsize);
 785int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
 786int fdt_finish_reservemap(void *fdt);
 787int fdt_begin_node(void *fdt, const char *name);
 788int fdt_property(void *fdt, const char *name, const void *val, int len);
 789static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
 790{
 791	val = cpu_to_fdt32(val);
 792	return fdt_property(fdt, name, &val, sizeof(val));
 793}
 
 
 
 
 
 
 
 
 
 794#define fdt_property_string(fdt, name, str) \
 795	fdt_property(fdt, name, str, strlen(str)+1)
 796int fdt_end_node(void *fdt);
 797int fdt_finish(void *fdt);
 798
 799/**********************************************************************/
 800/* Read-write functions                                               */
 801/**********************************************************************/
 802
 
 803int fdt_open_into(const void *fdt, void *buf, int bufsize);
 804int fdt_pack(void *fdt);
 805
 806/**
 807 * fdt_add_mem_rsv - add one memory reserve map entry
 808 * @fdt: pointer to the device tree blob
 809 * @address, @size: 64-bit values (native endian)
 810 *
 811 * Adds a reserve map entry to the given blob reserving a region at
 812 * address address of length size.
 813 *
 814 * This function will insert data into the reserve map and will
 815 * therefore change the indexes of some entries in the table.
 816 *
 817 * returns:
 818 *	0, on success
 819 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 820 *		contain the new reservation entry
 821 *	-FDT_ERR_BADMAGIC,
 822 *	-FDT_ERR_BADVERSION,
 823 *	-FDT_ERR_BADSTATE,
 824 *	-FDT_ERR_BADSTRUCTURE,
 825 *	-FDT_ERR_BADLAYOUT,
 826 *	-FDT_ERR_TRUNCATED, standard meanings
 827 */
 828int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
 829
 830/**
 831 * fdt_del_mem_rsv - remove a memory reserve map entry
 832 * @fdt: pointer to the device tree blob
 833 * @n: entry to remove
 834 *
 835 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
 836 * the blob.
 837 *
 838 * This function will delete data from the reservation table and will
 839 * therefore change the indexes of some entries in the table.
 840 *
 841 * returns:
 842 *	0, on success
 843 *	-FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
 844 *		are less than n+1 reserve map entries)
 845 *	-FDT_ERR_BADMAGIC,
 846 *	-FDT_ERR_BADVERSION,
 847 *	-FDT_ERR_BADSTATE,
 848 *	-FDT_ERR_BADSTRUCTURE,
 849 *	-FDT_ERR_BADLAYOUT,
 850 *	-FDT_ERR_TRUNCATED, standard meanings
 851 */
 852int fdt_del_mem_rsv(void *fdt, int n);
 853
 854/**
 855 * fdt_set_name - change the name of a given node
 856 * @fdt: pointer to the device tree blob
 857 * @nodeoffset: structure block offset of a node
 858 * @name: name to give the node
 859 *
 860 * fdt_set_name() replaces the name (including unit address, if any)
 861 * of the given node with the given string.  NOTE: this function can't
 862 * efficiently check if the new name is unique amongst the given
 863 * node's siblings; results are undefined if this function is invoked
 864 * with a name equal to one of the given node's siblings.
 865 *
 866 * This function may insert or delete data from the blob, and will
 867 * therefore change the offsets of some existing nodes.
 868 *
 869 * returns:
 870 *	0, on success
 871 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob
 872 *		to contain the new name
 873 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 874 *	-FDT_ERR_BADMAGIC,
 875 *	-FDT_ERR_BADVERSION,
 876 *	-FDT_ERR_BADSTATE, standard meanings
 877 */
 878int fdt_set_name(void *fdt, int nodeoffset, const char *name);
 879
 880/**
 881 * fdt_setprop - create or change a property
 882 * @fdt: pointer to the device tree blob
 883 * @nodeoffset: offset of the node whose property to change
 884 * @name: name of the property to change
 885 * @val: pointer to data to set the property value to
 886 * @len: length of the property value
 887 *
 888 * fdt_setprop() sets the value of the named property in the given
 889 * node to the given value and length, creating the property if it
 890 * does not already exist.
 891 *
 892 * This function may insert or delete data from the blob, and will
 893 * therefore change the offsets of some existing nodes.
 894 *
 895 * returns:
 896 *	0, on success
 897 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 898 *		contain the new property value
 899 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 900 *	-FDT_ERR_BADLAYOUT,
 901 *	-FDT_ERR_BADMAGIC,
 902 *	-FDT_ERR_BADVERSION,
 903 *	-FDT_ERR_BADSTATE,
 904 *	-FDT_ERR_BADSTRUCTURE,
 905 *	-FDT_ERR_BADLAYOUT,
 906 *	-FDT_ERR_TRUNCATED, standard meanings
 907 */
 908int fdt_setprop(void *fdt, int nodeoffset, const char *name,
 909		const void *val, int len);
 910
 911/**
 912 * fdt_setprop_cell - set a property to a single cell value
 913 * @fdt: pointer to the device tree blob
 914 * @nodeoffset: offset of the node whose property to change
 915 * @name: name of the property to change
 916 * @val: 32-bit integer value for the property (native endian)
 917 *
 918 * fdt_setprop_cell() sets the value of the named property in the
 919 * given node to the given cell value (converting to big-endian if
 920 * necessary), or creates a new property with that value if it does
 921 * not already exist.
 922 *
 923 * This function may insert or delete data from the blob, and will
 924 * therefore change the offsets of some existing nodes.
 925 *
 926 * returns:
 927 *	0, on success
 928 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 929 *		contain the new property value
 930 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 931 *	-FDT_ERR_BADLAYOUT,
 932 *	-FDT_ERR_BADMAGIC,
 933 *	-FDT_ERR_BADVERSION,
 934 *	-FDT_ERR_BADSTATE,
 935 *	-FDT_ERR_BADSTRUCTURE,
 936 *	-FDT_ERR_BADLAYOUT,
 937 *	-FDT_ERR_TRUNCATED, standard meanings
 938 */
 939static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
 940				   uint32_t val)
 941{
 942	val = cpu_to_fdt32(val);
 943	return fdt_setprop(fdt, nodeoffset, name, &val, sizeof(val));
 944}
 945
 946/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 947 * fdt_setprop_string - set a property to a string value
 948 * @fdt: pointer to the device tree blob
 949 * @nodeoffset: offset of the node whose property to change
 950 * @name: name of the property to change
 951 * @str: string value for the property
 952 *
 953 * fdt_setprop_string() sets the value of the named property in the
 954 * given node to the given string value (using the length of the
 955 * string to determine the new length of the property), or creates a
 956 * new property with that value if it does not already exist.
 957 *
 958 * This function may insert or delete data from the blob, and will
 959 * therefore change the offsets of some existing nodes.
 960 *
 961 * returns:
 962 *	0, on success
 963 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 964 *		contain the new property value
 965 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 966 *	-FDT_ERR_BADLAYOUT,
 967 *	-FDT_ERR_BADMAGIC,
 968 *	-FDT_ERR_BADVERSION,
 969 *	-FDT_ERR_BADSTATE,
 970 *	-FDT_ERR_BADSTRUCTURE,
 971 *	-FDT_ERR_BADLAYOUT,
 972 *	-FDT_ERR_TRUNCATED, standard meanings
 973 */
 974#define fdt_setprop_string(fdt, nodeoffset, name, str) \
 975	fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 976
 977/**
 978 * fdt_delprop - delete a property
 979 * @fdt: pointer to the device tree blob
 980 * @nodeoffset: offset of the node whose property to nop
 981 * @name: name of the property to nop
 982 *
 983 * fdt_del_property() will delete the given property.
 984 *
 985 * This function will delete data from the blob, and will therefore
 986 * change the offsets of some existing nodes.
 987 *
 988 * returns:
 989 *	0, on success
 990 *	-FDT_ERR_NOTFOUND, node does not have the named property
 991 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 992 *	-FDT_ERR_BADLAYOUT,
 993 *	-FDT_ERR_BADMAGIC,
 994 *	-FDT_ERR_BADVERSION,
 995 *	-FDT_ERR_BADSTATE,
 996 *	-FDT_ERR_BADSTRUCTURE,
 997 *	-FDT_ERR_TRUNCATED, standard meanings
 998 */
 999int fdt_delprop(void *fdt, int nodeoffset, const char *name);
1000
1001/**
1002 * fdt_add_subnode_namelen - creates a new node based on substring
1003 * @fdt: pointer to the device tree blob
1004 * @parentoffset: structure block offset of a node
1005 * @name: name of the subnode to locate
1006 * @namelen: number of characters of name to consider
1007 *
1008 * Identical to fdt_add_subnode(), but use only the first namelen
1009 * characters of name as the name of the new node.  This is useful for
1010 * creating subnodes based on a portion of a larger string, such as a
1011 * full path.
1012 */
1013int fdt_add_subnode_namelen(void *fdt, int parentoffset,
1014			    const char *name, int namelen);
1015
1016/**
1017 * fdt_add_subnode - creates a new node
1018 * @fdt: pointer to the device tree blob
1019 * @parentoffset: structure block offset of a node
1020 * @name: name of the subnode to locate
1021 *
1022 * fdt_add_subnode() creates a new node as a subnode of the node at
1023 * structure block offset parentoffset, with the given name (which
1024 * should include the unit address, if any).
1025 *
1026 * This function will insert data into the blob, and will therefore
1027 * change the offsets of some existing nodes.
1028
1029 * returns:
1030 *	structure block offset of the created nodeequested subnode (>=0), on success
1031 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
1032 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
1033 *	-FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
1034 *		the given name
1035 *	-FDT_ERR_NOSPACE, if there is insufficient free space in the
1036 *		blob to contain the new node
1037 *	-FDT_ERR_NOSPACE
1038 *	-FDT_ERR_BADLAYOUT
1039 *      -FDT_ERR_BADMAGIC,
1040 *	-FDT_ERR_BADVERSION,
1041 *	-FDT_ERR_BADSTATE,
1042 *	-FDT_ERR_BADSTRUCTURE,
1043 *	-FDT_ERR_TRUNCATED, standard meanings.
1044 */
1045int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
1046
1047/**
1048 * fdt_del_node - delete a node (subtree)
1049 * @fdt: pointer to the device tree blob
1050 * @nodeoffset: offset of the node to nop
1051 *
1052 * fdt_del_node() will remove the given node, including all its
1053 * subnodes if any, from the blob.
1054 *
1055 * This function will delete data from the blob, and will therefore
1056 * change the offsets of some existing nodes.
1057 *
1058 * returns:
1059 *	0, on success
1060 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1061 *	-FDT_ERR_BADLAYOUT,
1062 *	-FDT_ERR_BADMAGIC,
1063 *	-FDT_ERR_BADVERSION,
1064 *	-FDT_ERR_BADSTATE,
1065 *	-FDT_ERR_BADSTRUCTURE,
1066 *	-FDT_ERR_TRUNCATED, standard meanings
1067 */
1068int fdt_del_node(void *fdt, int nodeoffset);
1069
1070/**********************************************************************/
1071/* Debugging / informational functions                                */
1072/**********************************************************************/
1073
1074const char *fdt_strerror(int errval);
1075
1076#endif /* _LIBFDT_H */
v3.15
   1#ifndef _LIBFDT_H
   2#define _LIBFDT_H
   3/*
   4 * libfdt - Flat Device Tree manipulation
   5 * Copyright (C) 2006 David Gibson, IBM Corporation.
   6 *
   7 * libfdt is dual licensed: you can use it either under the terms of
   8 * the GPL, or the BSD license, at your option.
   9 *
  10 *  a) This library is free software; you can redistribute it and/or
  11 *     modify it under the terms of the GNU General Public License as
  12 *     published by the Free Software Foundation; either version 2 of the
  13 *     License, or (at your option) any later version.
  14 *
  15 *     This library is distributed in the hope that it will be useful,
  16 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 *     GNU General Public License for more details.
  19 *
  20 *     You should have received a copy of the GNU General Public
  21 *     License along with this library; if not, write to the Free
  22 *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  23 *     MA 02110-1301 USA
  24 *
  25 * Alternatively,
  26 *
  27 *  b) Redistribution and use in source and binary forms, with or
  28 *     without modification, are permitted provided that the following
  29 *     conditions are met:
  30 *
  31 *     1. Redistributions of source code must retain the above
  32 *        copyright notice, this list of conditions and the following
  33 *        disclaimer.
  34 *     2. Redistributions in binary form must reproduce the above
  35 *        copyright notice, this list of conditions and the following
  36 *        disclaimer in the documentation and/or other materials
  37 *        provided with the distribution.
  38 *
  39 *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  40 *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  41 *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  42 *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  43 *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  44 *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45 *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46 *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47 *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48 *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  49 *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  50 *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
  51 *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  52 */
  53
  54#include <libfdt_env.h>
  55#include <fdt.h>
  56
  57#define FDT_FIRST_SUPPORTED_VERSION	0x10
  58#define FDT_LAST_SUPPORTED_VERSION	0x11
  59
  60/* Error codes: informative error codes */
  61#define FDT_ERR_NOTFOUND	1
  62	/* FDT_ERR_NOTFOUND: The requested node or property does not exist */
  63#define FDT_ERR_EXISTS		2
  64	/* FDT_ERR_EXISTS: Attemped to create a node or property which
  65	 * already exists */
  66#define FDT_ERR_NOSPACE		3
  67	/* FDT_ERR_NOSPACE: Operation needed to expand the device
  68	 * tree, but its buffer did not have sufficient space to
  69	 * contain the expanded tree. Use fdt_open_into() to move the
  70	 * device tree to a buffer with more space. */
  71
  72/* Error codes: codes for bad parameters */
  73#define FDT_ERR_BADOFFSET	4
  74	/* FDT_ERR_BADOFFSET: Function was passed a structure block
  75	 * offset which is out-of-bounds, or which points to an
  76	 * unsuitable part of the structure for the operation. */
  77#define FDT_ERR_BADPATH		5
  78	/* FDT_ERR_BADPATH: Function was passed a badly formatted path
  79	 * (e.g. missing a leading / for a function which requires an
  80	 * absolute path) */
  81#define FDT_ERR_BADPHANDLE	6
  82	/* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle
  83	 * value.  phandle values of 0 and -1 are not permitted. */
  84#define FDT_ERR_BADSTATE	7
  85	/* FDT_ERR_BADSTATE: Function was passed an incomplete device
  86	 * tree created by the sequential-write functions, which is
  87	 * not sufficiently complete for the requested operation. */
  88
  89/* Error codes: codes for bad device tree blobs */
  90#define FDT_ERR_TRUNCATED	8
  91	/* FDT_ERR_TRUNCATED: Structure block of the given device tree
  92	 * ends without an FDT_END tag. */
  93#define FDT_ERR_BADMAGIC	9
  94	/* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
  95	 * device tree at all - it is missing the flattened device
  96	 * tree magic number. */
  97#define FDT_ERR_BADVERSION	10
  98	/* FDT_ERR_BADVERSION: Given device tree has a version which
  99	 * can't be handled by the requested operation.  For
 100	 * read-write functions, this may mean that fdt_open_into() is
 101	 * required to convert the tree to the expected version. */
 102#define FDT_ERR_BADSTRUCTURE	11
 103	/* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt
 104	 * structure block or other serious error (e.g. misnested
 105	 * nodes, or subnodes preceding properties). */
 106#define FDT_ERR_BADLAYOUT	12
 107	/* FDT_ERR_BADLAYOUT: For read-write functions, the given
 108	 * device tree has it's sub-blocks in an order that the
 109	 * function can't handle (memory reserve map, then structure,
 110	 * then strings).  Use fdt_open_into() to reorganize the tree
 111	 * into a form suitable for the read-write operations. */
 112
 113/* "Can't happen" error indicating a bug in libfdt */
 114#define FDT_ERR_INTERNAL	13
 115	/* FDT_ERR_INTERNAL: libfdt has failed an internal assertion.
 116	 * Should never be returned, if it is, it indicates a bug in
 117	 * libfdt itself. */
 118
 119#define FDT_ERR_MAX		13
 120
 121/**********************************************************************/
 122/* Low-level functions (you probably don't need these)                */
 123/**********************************************************************/
 124
 125const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen);
 126static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
 127{
 128	return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
 129}
 130
 131uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
 132
 133/**********************************************************************/
 134/* Traversal functions                                                */
 135/**********************************************************************/
 136
 137int fdt_next_node(const void *fdt, int offset, int *depth);
 138
 139/**********************************************************************/
 140/* General functions                                                  */
 141/**********************************************************************/
 142
 143#define fdt_get_header(fdt, field) \
 144	(fdt32_to_cpu(((const struct fdt_header *)(fdt))->field))
 145#define fdt_magic(fdt) 			(fdt_get_header(fdt, magic))
 146#define fdt_totalsize(fdt)		(fdt_get_header(fdt, totalsize))
 147#define fdt_off_dt_struct(fdt)		(fdt_get_header(fdt, off_dt_struct))
 148#define fdt_off_dt_strings(fdt)		(fdt_get_header(fdt, off_dt_strings))
 149#define fdt_off_mem_rsvmap(fdt)		(fdt_get_header(fdt, off_mem_rsvmap))
 150#define fdt_version(fdt)		(fdt_get_header(fdt, version))
 151#define fdt_last_comp_version(fdt) 	(fdt_get_header(fdt, last_comp_version))
 152#define fdt_boot_cpuid_phys(fdt) 	(fdt_get_header(fdt, boot_cpuid_phys))
 153#define fdt_size_dt_strings(fdt) 	(fdt_get_header(fdt, size_dt_strings))
 154#define fdt_size_dt_struct(fdt)		(fdt_get_header(fdt, size_dt_struct))
 155
 156#define __fdt_set_hdr(name) \
 157	static inline void fdt_set_##name(void *fdt, uint32_t val) \
 158	{ \
 159		struct fdt_header *fdth = (struct fdt_header*)fdt; \
 160		fdth->name = cpu_to_fdt32(val); \
 161	}
 162__fdt_set_hdr(magic);
 163__fdt_set_hdr(totalsize);
 164__fdt_set_hdr(off_dt_struct);
 165__fdt_set_hdr(off_dt_strings);
 166__fdt_set_hdr(off_mem_rsvmap);
 167__fdt_set_hdr(version);
 168__fdt_set_hdr(last_comp_version);
 169__fdt_set_hdr(boot_cpuid_phys);
 170__fdt_set_hdr(size_dt_strings);
 171__fdt_set_hdr(size_dt_struct);
 172#undef __fdt_set_hdr
 173
 174/**
 175 * fdt_check_header - sanity check a device tree or possible device tree
 176 * @fdt: pointer to data which might be a flattened device tree
 177 *
 178 * fdt_check_header() checks that the given buffer contains what
 179 * appears to be a flattened device tree with sane information in its
 180 * header.
 181 *
 182 * returns:
 183 *     0, if the buffer appears to contain a valid device tree
 184 *     -FDT_ERR_BADMAGIC,
 185 *     -FDT_ERR_BADVERSION,
 186 *     -FDT_ERR_BADSTATE, standard meanings, as above
 187 */
 188int fdt_check_header(const void *fdt);
 189
 190/**
 191 * fdt_move - move a device tree around in memory
 192 * @fdt: pointer to the device tree to move
 193 * @buf: pointer to memory where the device is to be moved
 194 * @bufsize: size of the memory space at buf
 195 *
 196 * fdt_move() relocates, if possible, the device tree blob located at
 197 * fdt to the buffer at buf of size bufsize.  The buffer may overlap
 198 * with the existing device tree blob at fdt.  Therefore,
 199 *     fdt_move(fdt, fdt, fdt_totalsize(fdt))
 200 * should always succeed.
 201 *
 202 * returns:
 203 *     0, on success
 204 *     -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
 205 *     -FDT_ERR_BADMAGIC,
 206 *     -FDT_ERR_BADVERSION,
 207 *     -FDT_ERR_BADSTATE, standard meanings
 208 */
 209int fdt_move(const void *fdt, void *buf, int bufsize);
 210
 211/**********************************************************************/
 212/* Read-only functions                                                */
 213/**********************************************************************/
 214
 215/**
 216 * fdt_string - retrieve a string from the strings block of a device tree
 217 * @fdt: pointer to the device tree blob
 218 * @stroffset: offset of the string within the strings block (native endian)
 219 *
 220 * fdt_string() retrieves a pointer to a single string from the
 221 * strings block of the device tree blob at fdt.
 222 *
 223 * returns:
 224 *     a pointer to the string, on success
 225 *     NULL, if stroffset is out of bounds
 226 */
 227const char *fdt_string(const void *fdt, int stroffset);
 228
 229/**
 230 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
 231 * @fdt: pointer to the device tree blob
 232 *
 233 * Returns the number of entries in the device tree blob's memory
 234 * reservation map.  This does not include the terminating 0,0 entry
 235 * or any other (0,0) entries reserved for expansion.
 236 *
 237 * returns:
 238 *     the number of entries
 239 */
 240int fdt_num_mem_rsv(const void *fdt);
 241
 242/**
 243 * fdt_get_mem_rsv - retrieve one memory reserve map entry
 244 * @fdt: pointer to the device tree blob
 245 * @address, @size: pointers to 64-bit variables
 246 *
 247 * On success, *address and *size will contain the address and size of
 248 * the n-th reserve map entry from the device tree blob, in
 249 * native-endian format.
 250 *
 251 * returns:
 252 *     0, on success
 253 *     -FDT_ERR_BADMAGIC,
 254 *     -FDT_ERR_BADVERSION,
 255 *     -FDT_ERR_BADSTATE, standard meanings
 256 */
 257int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
 258
 259/**
 260 * fdt_subnode_offset_namelen - find a subnode based on substring
 261 * @fdt: pointer to the device tree blob
 262 * @parentoffset: structure block offset of a node
 263 * @name: name of the subnode to locate
 264 * @namelen: number of characters of name to consider
 265 *
 266 * Identical to fdt_subnode_offset(), but only examine the first
 267 * namelen characters of name for matching the subnode name.  This is
 268 * useful for finding subnodes based on a portion of a larger string,
 269 * such as a full path.
 270 */
 271int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
 272			       const char *name, int namelen);
 273/**
 274 * fdt_subnode_offset - find a subnode of a given node
 275 * @fdt: pointer to the device tree blob
 276 * @parentoffset: structure block offset of a node
 277 * @name: name of the subnode to locate
 278 *
 279 * fdt_subnode_offset() finds a subnode of the node at structure block
 280 * offset parentoffset with the given name.  name may include a unit
 281 * address, in which case fdt_subnode_offset() will find the subnode
 282 * with that unit address, or the unit address may be omitted, in
 283 * which case fdt_subnode_offset() will find an arbitrary subnode
 284 * whose name excluding unit address matches the given name.
 285 *
 286 * returns:
 287 *	structure block offset of the requested subnode (>=0), on success
 288 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
 289 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
 290 *      -FDT_ERR_BADMAGIC,
 291 *	-FDT_ERR_BADVERSION,
 292 *	-FDT_ERR_BADSTATE,
 293 *	-FDT_ERR_BADSTRUCTURE,
 294 *	-FDT_ERR_TRUNCATED, standard meanings.
 295 */
 296int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
 297
 298/**
 299 * fdt_path_offset - find a tree node by its full path
 300 * @fdt: pointer to the device tree blob
 301 * @path: full path of the node to locate
 302 *
 303 * fdt_path_offset() finds a node of a given path in the device tree.
 304 * Each path component may omit the unit address portion, but the
 305 * results of this are undefined if any such path component is
 306 * ambiguous (that is if there are multiple nodes at the relevant
 307 * level matching the given component, differentiated only by unit
 308 * address).
 309 *
 310 * returns:
 311 *	structure block offset of the node with the requested path (>=0), on success
 312 *	-FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
 313 *	-FDT_ERR_NOTFOUND, if the requested node does not exist
 314 *      -FDT_ERR_BADMAGIC,
 315 *	-FDT_ERR_BADVERSION,
 316 *	-FDT_ERR_BADSTATE,
 317 *	-FDT_ERR_BADSTRUCTURE,
 318 *	-FDT_ERR_TRUNCATED, standard meanings.
 319 */
 320int fdt_path_offset(const void *fdt, const char *path);
 321
 322/**
 323 * fdt_get_name - retrieve the name of a given node
 324 * @fdt: pointer to the device tree blob
 325 * @nodeoffset: structure block offset of the starting node
 326 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 327 *
 328 * fdt_get_name() retrieves the name (including unit address) of the
 329 * device tree node at structure block offset nodeoffset.  If lenp is
 330 * non-NULL, the length of this name is also returned, in the integer
 331 * pointed to by lenp.
 332 *
 333 * returns:
 334 *	pointer to the node's name, on success
 335 *		If lenp is non-NULL, *lenp contains the length of that name (>=0)
 336 *	NULL, on error
 337 *		if lenp is non-NULL *lenp contains an error code (<0):
 338 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 339 *		-FDT_ERR_BADMAGIC,
 340 *		-FDT_ERR_BADVERSION,
 341 *		-FDT_ERR_BADSTATE, standard meanings
 342 */
 343const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
 344
 345/**
 346 * fdt_first_property_offset - find the offset of a node's first property
 347 * @fdt: pointer to the device tree blob
 348 * @nodeoffset: structure block offset of a node
 349 *
 350 * fdt_first_property_offset() finds the first property of the node at
 351 * the given structure block offset.
 352 *
 353 * returns:
 354 *	structure block offset of the property (>=0), on success
 355 *	-FDT_ERR_NOTFOUND, if the requested node has no properties
 356 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
 357 *      -FDT_ERR_BADMAGIC,
 358 *	-FDT_ERR_BADVERSION,
 359 *	-FDT_ERR_BADSTATE,
 360 *	-FDT_ERR_BADSTRUCTURE,
 361 *	-FDT_ERR_TRUNCATED, standard meanings.
 362 */
 363int fdt_first_property_offset(const void *fdt, int nodeoffset);
 364
 365/**
 366 * fdt_next_property_offset - step through a node's properties
 367 * @fdt: pointer to the device tree blob
 368 * @offset: structure block offset of a property
 369 *
 370 * fdt_next_property_offset() finds the property immediately after the
 371 * one at the given structure block offset.  This will be a property
 372 * of the same node as the given property.
 373 *
 374 * returns:
 375 *	structure block offset of the next property (>=0), on success
 376 *	-FDT_ERR_NOTFOUND, if the given property is the last in its node
 377 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag
 378 *      -FDT_ERR_BADMAGIC,
 379 *	-FDT_ERR_BADVERSION,
 380 *	-FDT_ERR_BADSTATE,
 381 *	-FDT_ERR_BADSTRUCTURE,
 382 *	-FDT_ERR_TRUNCATED, standard meanings.
 383 */
 384int fdt_next_property_offset(const void *fdt, int offset);
 385
 386/**
 387 * fdt_get_property_by_offset - retrieve the property at a given offset
 388 * @fdt: pointer to the device tree blob
 389 * @offset: offset of the property to retrieve
 390 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 391 *
 392 * fdt_get_property_by_offset() retrieves a pointer to the
 393 * fdt_property structure within the device tree blob at the given
 394 * offset.  If lenp is non-NULL, the length of the property value is
 395 * also returned, in the integer pointed to by lenp.
 396 *
 397 * returns:
 398 *	pointer to the structure representing the property
 399 *		if lenp is non-NULL, *lenp contains the length of the property
 400 *		value (>=0)
 401 *	NULL, on error
 402 *		if lenp is non-NULL, *lenp contains an error code (<0):
 403 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
 404 *		-FDT_ERR_BADMAGIC,
 405 *		-FDT_ERR_BADVERSION,
 406 *		-FDT_ERR_BADSTATE,
 407 *		-FDT_ERR_BADSTRUCTURE,
 408 *		-FDT_ERR_TRUNCATED, standard meanings
 409 */
 410const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
 411						      int offset,
 412						      int *lenp);
 413
 414/**
 415 * fdt_get_property_namelen - find a property based on substring
 416 * @fdt: pointer to the device tree blob
 417 * @nodeoffset: offset of the node whose property to find
 418 * @name: name of the property to find
 419 * @namelen: number of characters of name to consider
 420 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 421 *
 422 * Identical to fdt_get_property_namelen(), but only examine the first
 423 * namelen characters of name for matching the property name.
 424 */
 425const struct fdt_property *fdt_get_property_namelen(const void *fdt,
 426						    int nodeoffset,
 427						    const char *name,
 428						    int namelen, int *lenp);
 429
 430/**
 431 * fdt_get_property - find a given property in a given node
 432 * @fdt: pointer to the device tree blob
 433 * @nodeoffset: offset of the node whose property to find
 434 * @name: name of the property to find
 435 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 436 *
 437 * fdt_get_property() retrieves a pointer to the fdt_property
 438 * structure within the device tree blob corresponding to the property
 439 * named 'name' of the node at offset nodeoffset.  If lenp is
 440 * non-NULL, the length of the property value is also returned, in the
 441 * integer pointed to by lenp.
 442 *
 443 * returns:
 444 *	pointer to the structure representing the property
 445 *		if lenp is non-NULL, *lenp contains the length of the property
 446 *		value (>=0)
 447 *	NULL, on error
 448 *		if lenp is non-NULL, *lenp contains an error code (<0):
 449 *		-FDT_ERR_NOTFOUND, node does not have named property
 450 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 451 *		-FDT_ERR_BADMAGIC,
 452 *		-FDT_ERR_BADVERSION,
 453 *		-FDT_ERR_BADSTATE,
 454 *		-FDT_ERR_BADSTRUCTURE,
 455 *		-FDT_ERR_TRUNCATED, standard meanings
 456 */
 457const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
 458					    const char *name, int *lenp);
 459static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
 460						      const char *name,
 461						      int *lenp)
 462{
 463	return (struct fdt_property *)(uintptr_t)
 464		fdt_get_property(fdt, nodeoffset, name, lenp);
 465}
 466
 467/**
 468 * fdt_getprop_by_offset - retrieve the value of a property at a given offset
 469 * @fdt: pointer to the device tree blob
 470 * @ffset: offset of the property to read
 471 * @namep: pointer to a string variable (will be overwritten) or NULL
 472 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 473 *
 474 * fdt_getprop_by_offset() retrieves a pointer to the value of the
 475 * property at structure block offset 'offset' (this will be a pointer
 476 * to within the device blob itself, not a copy of the value).  If
 477 * lenp is non-NULL, the length of the property value is also
 478 * returned, in the integer pointed to by lenp.  If namep is non-NULL,
 479 * the property's namne will also be returned in the char * pointed to
 480 * by namep (this will be a pointer to within the device tree's string
 481 * block, not a new copy of the name).
 482 *
 483 * returns:
 484 *	pointer to the property's value
 485 *		if lenp is non-NULL, *lenp contains the length of the property
 486 *		value (>=0)
 487 *		if namep is non-NULL *namep contiains a pointer to the property
 488 *		name.
 489 *	NULL, on error
 490 *		if lenp is non-NULL, *lenp contains an error code (<0):
 491 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
 492 *		-FDT_ERR_BADMAGIC,
 493 *		-FDT_ERR_BADVERSION,
 494 *		-FDT_ERR_BADSTATE,
 495 *		-FDT_ERR_BADSTRUCTURE,
 496 *		-FDT_ERR_TRUNCATED, standard meanings
 497 */
 498const void *fdt_getprop_by_offset(const void *fdt, int offset,
 499				  const char **namep, int *lenp);
 500
 501/**
 502 * fdt_getprop_namelen - get property value based on substring
 503 * @fdt: pointer to the device tree blob
 504 * @nodeoffset: offset of the node whose property to find
 505 * @name: name of the property to find
 506 * @namelen: number of characters of name to consider
 507 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 508 *
 509 * Identical to fdt_getprop(), but only examine the first namelen
 510 * characters of name for matching the property name.
 511 */
 512const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
 513				const char *name, int namelen, int *lenp);
 514
 515/**
 516 * fdt_getprop - retrieve the value of a given property
 517 * @fdt: pointer to the device tree blob
 518 * @nodeoffset: offset of the node whose property to find
 519 * @name: name of the property to find
 520 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 521 *
 522 * fdt_getprop() retrieves a pointer to the value of the property
 523 * named 'name' of the node at offset nodeoffset (this will be a
 524 * pointer to within the device blob itself, not a copy of the value).
 525 * If lenp is non-NULL, the length of the property value is also
 526 * returned, in the integer pointed to by lenp.
 527 *
 528 * returns:
 529 *	pointer to the property's value
 530 *		if lenp is non-NULL, *lenp contains the length of the property
 531 *		value (>=0)
 532 *	NULL, on error
 533 *		if lenp is non-NULL, *lenp contains an error code (<0):
 534 *		-FDT_ERR_NOTFOUND, node does not have named property
 535 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 536 *		-FDT_ERR_BADMAGIC,
 537 *		-FDT_ERR_BADVERSION,
 538 *		-FDT_ERR_BADSTATE,
 539 *		-FDT_ERR_BADSTRUCTURE,
 540 *		-FDT_ERR_TRUNCATED, standard meanings
 541 */
 542const void *fdt_getprop(const void *fdt, int nodeoffset,
 543			const char *name, int *lenp);
 544static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
 545				  const char *name, int *lenp)
 546{
 547	return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
 548}
 549
 550/**
 551 * fdt_get_phandle - retrieve the phandle of a given node
 552 * @fdt: pointer to the device tree blob
 553 * @nodeoffset: structure block offset of the node
 554 *
 555 * fdt_get_phandle() retrieves the phandle of the device tree node at
 556 * structure block offset nodeoffset.
 557 *
 558 * returns:
 559 *	the phandle of the node at nodeoffset, on success (!= 0, != -1)
 560 *	0, if the node has no phandle, or another error occurs
 561 */
 562uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
 563
 564/**
 565 * fdt_get_alias_namelen - get alias based on substring
 566 * @fdt: pointer to the device tree blob
 567 * @name: name of the alias th look up
 568 * @namelen: number of characters of name to consider
 569 *
 570 * Identical to fdt_get_alias(), but only examine the first namelen
 571 * characters of name for matching the alias name.
 572 */
 573const char *fdt_get_alias_namelen(const void *fdt,
 574				  const char *name, int namelen);
 575
 576/**
 577 * fdt_get_alias - retreive the path referenced by a given alias
 578 * @fdt: pointer to the device tree blob
 579 * @name: name of the alias th look up
 580 *
 581 * fdt_get_alias() retrieves the value of a given alias.  That is, the
 582 * value of the property named 'name' in the node /aliases.
 583 *
 584 * returns:
 585 *	a pointer to the expansion of the alias named 'name', of it exists
 586 *	NULL, if the given alias or the /aliases node does not exist
 587 */
 588const char *fdt_get_alias(const void *fdt, const char *name);
 589
 590/**
 591 * fdt_get_path - determine the full path of a node
 592 * @fdt: pointer to the device tree blob
 593 * @nodeoffset: offset of the node whose path to find
 594 * @buf: character buffer to contain the returned path (will be overwritten)
 595 * @buflen: size of the character buffer at buf
 596 *
 597 * fdt_get_path() computes the full path of the node at offset
 598 * nodeoffset, and records that path in the buffer at buf.
 599 *
 600 * NOTE: This function is expensive, as it must scan the device tree
 601 * structure from the start to nodeoffset.
 602 *
 603 * returns:
 604 *	0, on success
 605 *		buf contains the absolute path of the node at
 606 *		nodeoffset, as a NUL-terminated string.
 607 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 608 *	-FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
 609 *		characters and will not fit in the given buffer.
 610 *	-FDT_ERR_BADMAGIC,
 611 *	-FDT_ERR_BADVERSION,
 612 *	-FDT_ERR_BADSTATE,
 613 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 614 */
 615int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
 616
 617/**
 618 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
 619 * @fdt: pointer to the device tree blob
 620 * @nodeoffset: offset of the node whose parent to find
 621 * @supernodedepth: depth of the ancestor to find
 622 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
 623 *
 624 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
 625 * at a specific depth from the root (where the root itself has depth
 626 * 0, its immediate subnodes depth 1 and so forth).  So
 627 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
 628 * will always return 0, the offset of the root node.  If the node at
 629 * nodeoffset has depth D, then:
 630 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
 631 * will return nodeoffset itself.
 632 *
 633 * NOTE: This function is expensive, as it must scan the device tree
 634 * structure from the start to nodeoffset.
 635 *
 636 * returns:
 637
 638 *	structure block offset of the node at node offset's ancestor
 639 *		of depth supernodedepth (>=0), on success
 640 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 641*	-FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of nodeoffset
 642 *	-FDT_ERR_BADMAGIC,
 643 *	-FDT_ERR_BADVERSION,
 644 *	-FDT_ERR_BADSTATE,
 645 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 646 */
 647int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
 648				 int supernodedepth, int *nodedepth);
 649
 650/**
 651 * fdt_node_depth - find the depth of a given node
 652 * @fdt: pointer to the device tree blob
 653 * @nodeoffset: offset of the node whose parent to find
 654 *
 655 * fdt_node_depth() finds the depth of a given node.  The root node
 656 * has depth 0, its immediate subnodes depth 1 and so forth.
 657 *
 658 * NOTE: This function is expensive, as it must scan the device tree
 659 * structure from the start to nodeoffset.
 660 *
 661 * returns:
 662 *	depth of the node at nodeoffset (>=0), on success
 663 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 664 *	-FDT_ERR_BADMAGIC,
 665 *	-FDT_ERR_BADVERSION,
 666 *	-FDT_ERR_BADSTATE,
 667 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 668 */
 669int fdt_node_depth(const void *fdt, int nodeoffset);
 670
 671/**
 672 * fdt_parent_offset - find the parent of a given node
 673 * @fdt: pointer to the device tree blob
 674 * @nodeoffset: offset of the node whose parent to find
 675 *
 676 * fdt_parent_offset() locates the parent node of a given node (that
 677 * is, it finds the offset of the node which contains the node at
 678 * nodeoffset as a subnode).
 679 *
 680 * NOTE: This function is expensive, as it must scan the device tree
 681 * structure from the start to nodeoffset, *twice*.
 682 *
 683 * returns:
 684 *	structure block offset of the parent of the node at nodeoffset
 685 *		(>=0), on success
 686 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 687 *	-FDT_ERR_BADMAGIC,
 688 *	-FDT_ERR_BADVERSION,
 689 *	-FDT_ERR_BADSTATE,
 690 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 691 */
 692int fdt_parent_offset(const void *fdt, int nodeoffset);
 693
 694/**
 695 * fdt_node_offset_by_prop_value - find nodes with a given property value
 696 * @fdt: pointer to the device tree blob
 697 * @startoffset: only find nodes after this offset
 698 * @propname: property name to check
 699 * @propval: property value to search for
 700 * @proplen: length of the value in propval
 701 *
 702 * fdt_node_offset_by_prop_value() returns the offset of the first
 703 * node after startoffset, which has a property named propname whose
 704 * value is of length proplen and has value equal to propval; or if
 705 * startoffset is -1, the very first such node in the tree.
 706 *
 707 * To iterate through all nodes matching the criterion, the following
 708 * idiom can be used:
 709 *	offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
 710 *					       propval, proplen);
 711 *	while (offset != -FDT_ERR_NOTFOUND) {
 712 *		// other code here
 713 *		offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
 714 *						       propval, proplen);
 715 *	}
 716 *
 717 * Note the -1 in the first call to the function, if 0 is used here
 718 * instead, the function will never locate the root node, even if it
 719 * matches the criterion.
 720 *
 721 * returns:
 722 *	structure block offset of the located node (>= 0, >startoffset),
 723 *		 on success
 724 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
 725 *		tree after startoffset
 726 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 727 *	-FDT_ERR_BADMAGIC,
 728 *	-FDT_ERR_BADVERSION,
 729 *	-FDT_ERR_BADSTATE,
 730 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 731 */
 732int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
 733				  const char *propname,
 734				  const void *propval, int proplen);
 735
 736/**
 737 * fdt_node_offset_by_phandle - find the node with a given phandle
 738 * @fdt: pointer to the device tree blob
 739 * @phandle: phandle value
 740 *
 741 * fdt_node_offset_by_phandle() returns the offset of the node
 742 * which has the given phandle value.  If there is more than one node
 743 * in the tree with the given phandle (an invalid tree), results are
 744 * undefined.
 745 *
 746 * returns:
 747 *	structure block offset of the located node (>= 0), on success
 748 *	-FDT_ERR_NOTFOUND, no node with that phandle exists
 749 *	-FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
 750 *	-FDT_ERR_BADMAGIC,
 751 *	-FDT_ERR_BADVERSION,
 752 *	-FDT_ERR_BADSTATE,
 753 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 754 */
 755int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
 756
 757/**
 758 * fdt_node_check_compatible: check a node's compatible property
 759 * @fdt: pointer to the device tree blob
 760 * @nodeoffset: offset of a tree node
 761 * @compatible: string to match against
 762 *
 763 *
 764 * fdt_node_check_compatible() returns 0 if the given node contains a
 765 * 'compatible' property with the given string as one of its elements,
 766 * it returns non-zero otherwise, or on error.
 767 *
 768 * returns:
 769 *	0, if the node has a 'compatible' property listing the given string
 770 *	1, if the node has a 'compatible' property, but it does not list
 771 *		the given string
 772 *	-FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
 773 * 	-FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
 774 *	-FDT_ERR_BADMAGIC,
 775 *	-FDT_ERR_BADVERSION,
 776 *	-FDT_ERR_BADSTATE,
 777 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 778 */
 779int fdt_node_check_compatible(const void *fdt, int nodeoffset,
 780			      const char *compatible);
 781
 782/**
 783 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
 784 * @fdt: pointer to the device tree blob
 785 * @startoffset: only find nodes after this offset
 786 * @compatible: 'compatible' string to match against
 787 *
 788 * fdt_node_offset_by_compatible() returns the offset of the first
 789 * node after startoffset, which has a 'compatible' property which
 790 * lists the given compatible string; or if startoffset is -1, the
 791 * very first such node in the tree.
 792 *
 793 * To iterate through all nodes matching the criterion, the following
 794 * idiom can be used:
 795 *	offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
 796 *	while (offset != -FDT_ERR_NOTFOUND) {
 797 *		// other code here
 798 *		offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
 799 *	}
 800 *
 801 * Note the -1 in the first call to the function, if 0 is used here
 802 * instead, the function will never locate the root node, even if it
 803 * matches the criterion.
 804 *
 805 * returns:
 806 *	structure block offset of the located node (>= 0, >startoffset),
 807 *		 on success
 808 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
 809 *		tree after startoffset
 810 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 811 *	-FDT_ERR_BADMAGIC,
 812 *	-FDT_ERR_BADVERSION,
 813 *	-FDT_ERR_BADSTATE,
 814 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 815 */
 816int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
 817				  const char *compatible);
 818
 819/**********************************************************************/
 820/* Write-in-place functions                                           */
 821/**********************************************************************/
 822
 823/**
 824 * fdt_setprop_inplace - change a property's value, but not its size
 825 * @fdt: pointer to the device tree blob
 826 * @nodeoffset: offset of the node whose property to change
 827 * @name: name of the property to change
 828 * @val: pointer to data to replace the property value with
 829 * @len: length of the property value
 830 *
 831 * fdt_setprop_inplace() replaces the value of a given property with
 832 * the data in val, of length len.  This function cannot change the
 833 * size of a property, and so will only work if len is equal to the
 834 * current length of the property.
 835 *
 836 * This function will alter only the bytes in the blob which contain
 837 * the given property value, and will not alter or move any other part
 838 * of the tree.
 839 *
 840 * returns:
 841 *	0, on success
 842 *	-FDT_ERR_NOSPACE, if len is not equal to the property's current length
 843 *	-FDT_ERR_NOTFOUND, node does not have the named property
 844 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 845 *	-FDT_ERR_BADMAGIC,
 846 *	-FDT_ERR_BADVERSION,
 847 *	-FDT_ERR_BADSTATE,
 848 *	-FDT_ERR_BADSTRUCTURE,
 849 *	-FDT_ERR_TRUNCATED, standard meanings
 850 */
 851int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
 852			const void *val, int len);
 853
 854/**
 855 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
 856 * @fdt: pointer to the device tree blob
 857 * @nodeoffset: offset of the node whose property to change
 858 * @name: name of the property to change
 859 * @val: 32-bit integer value to replace the property with
 860 *
 861 * fdt_setprop_inplace_u32() replaces the value of a given property
 862 * with the 32-bit integer value in val, converting val to big-endian
 863 * if necessary.  This function cannot change the size of a property,
 864 * and so will only work if the property already exists and has length
 865 * 4.
 866 *
 867 * This function will alter only the bytes in the blob which contain
 868 * the given property value, and will not alter or move any other part
 869 * of the tree.
 870 *
 871 * returns:
 872 *	0, on success
 873 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 4
 874 *	-FDT_ERR_NOTFOUND, node does not have the named property
 875 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 876 *	-FDT_ERR_BADMAGIC,
 877 *	-FDT_ERR_BADVERSION,
 878 *	-FDT_ERR_BADSTATE,
 879 *	-FDT_ERR_BADSTRUCTURE,
 880 *	-FDT_ERR_TRUNCATED, standard meanings
 881 */
 882static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
 883					  const char *name, uint32_t val)
 884{
 885	val = cpu_to_fdt32(val);
 886	return fdt_setprop_inplace(fdt, nodeoffset, name, &val, sizeof(val));
 887}
 888
 889/**
 890 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
 891 * @fdt: pointer to the device tree blob
 892 * @nodeoffset: offset of the node whose property to change
 893 * @name: name of the property to change
 894 * @val: 64-bit integer value to replace the property with
 895 *
 896 * fdt_setprop_inplace_u64() replaces the value of a given property
 897 * with the 64-bit integer value in val, converting val to big-endian
 898 * if necessary.  This function cannot change the size of a property,
 899 * and so will only work if the property already exists and has length
 900 * 8.
 901 *
 902 * This function will alter only the bytes in the blob which contain
 903 * the given property value, and will not alter or move any other part
 904 * of the tree.
 905 *
 906 * returns:
 907 *	0, on success
 908 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 8
 909 *	-FDT_ERR_NOTFOUND, node does not have the named property
 910 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 911 *	-FDT_ERR_BADMAGIC,
 912 *	-FDT_ERR_BADVERSION,
 913 *	-FDT_ERR_BADSTATE,
 914 *	-FDT_ERR_BADSTRUCTURE,
 915 *	-FDT_ERR_TRUNCATED, standard meanings
 916 */
 917static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
 918					  const char *name, uint64_t val)
 919{
 920	val = cpu_to_fdt64(val);
 921	return fdt_setprop_inplace(fdt, nodeoffset, name, &val, sizeof(val));
 922}
 923
 924/**
 925 * fdt_setprop_inplace_cell - change the value of a single-cell property
 926 *
 927 * This is an alternative name for fdt_setprop_inplace_u32()
 928 */
 929static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
 930					   const char *name, uint32_t val)
 931{
 932	return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
 933}
 934
 935/**
 936 * fdt_nop_property - replace a property with nop tags
 937 * @fdt: pointer to the device tree blob
 938 * @nodeoffset: offset of the node whose property to nop
 939 * @name: name of the property to nop
 940 *
 941 * fdt_nop_property() will replace a given property's representation
 942 * in the blob with FDT_NOP tags, effectively removing it from the
 943 * tree.
 944 *
 945 * This function will alter only the bytes in the blob which contain
 946 * the property, and will not alter or move any other part of the
 947 * tree.
 948 *
 949 * returns:
 950 *	0, on success
 951 *	-FDT_ERR_NOTFOUND, node does not have the named property
 952 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 953 *	-FDT_ERR_BADMAGIC,
 954 *	-FDT_ERR_BADVERSION,
 955 *	-FDT_ERR_BADSTATE,
 956 *	-FDT_ERR_BADSTRUCTURE,
 957 *	-FDT_ERR_TRUNCATED, standard meanings
 958 */
 959int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
 960
 961/**
 962 * fdt_nop_node - replace a node (subtree) with nop tags
 963 * @fdt: pointer to the device tree blob
 964 * @nodeoffset: offset of the node to nop
 965 *
 966 * fdt_nop_node() will replace a given node's representation in the
 967 * blob, including all its subnodes, if any, with FDT_NOP tags,
 968 * effectively removing it from the tree.
 969 *
 970 * This function will alter only the bytes in the blob which contain
 971 * the node and its properties and subnodes, and will not alter or
 972 * move any other part of the tree.
 973 *
 974 * returns:
 975 *	0, on success
 976 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 977 *	-FDT_ERR_BADMAGIC,
 978 *	-FDT_ERR_BADVERSION,
 979 *	-FDT_ERR_BADSTATE,
 980 *	-FDT_ERR_BADSTRUCTURE,
 981 *	-FDT_ERR_TRUNCATED, standard meanings
 982 */
 983int fdt_nop_node(void *fdt, int nodeoffset);
 984
 985/**********************************************************************/
 986/* Sequential write functions                                         */
 987/**********************************************************************/
 988
 989int fdt_create(void *buf, int bufsize);
 990int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
 991int fdt_finish_reservemap(void *fdt);
 992int fdt_begin_node(void *fdt, const char *name);
 993int fdt_property(void *fdt, const char *name, const void *val, int len);
 994static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
 995{
 996	val = cpu_to_fdt32(val);
 997	return fdt_property(fdt, name, &val, sizeof(val));
 998}
 999static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
1000{
1001	val = cpu_to_fdt64(val);
1002	return fdt_property(fdt, name, &val, sizeof(val));
1003}
1004static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
1005{
1006	return fdt_property_u32(fdt, name, val);
1007}
1008#define fdt_property_string(fdt, name, str) \
1009	fdt_property(fdt, name, str, strlen(str)+1)
1010int fdt_end_node(void *fdt);
1011int fdt_finish(void *fdt);
1012
1013/**********************************************************************/
1014/* Read-write functions                                               */
1015/**********************************************************************/
1016
1017int fdt_create_empty_tree(void *buf, int bufsize);
1018int fdt_open_into(const void *fdt, void *buf, int bufsize);
1019int fdt_pack(void *fdt);
1020
1021/**
1022 * fdt_add_mem_rsv - add one memory reserve map entry
1023 * @fdt: pointer to the device tree blob
1024 * @address, @size: 64-bit values (native endian)
1025 *
1026 * Adds a reserve map entry to the given blob reserving a region at
1027 * address address of length size.
1028 *
1029 * This function will insert data into the reserve map and will
1030 * therefore change the indexes of some entries in the table.
1031 *
1032 * returns:
1033 *	0, on success
1034 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1035 *		contain the new reservation entry
1036 *	-FDT_ERR_BADMAGIC,
1037 *	-FDT_ERR_BADVERSION,
1038 *	-FDT_ERR_BADSTATE,
1039 *	-FDT_ERR_BADSTRUCTURE,
1040 *	-FDT_ERR_BADLAYOUT,
1041 *	-FDT_ERR_TRUNCATED, standard meanings
1042 */
1043int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
1044
1045/**
1046 * fdt_del_mem_rsv - remove a memory reserve map entry
1047 * @fdt: pointer to the device tree blob
1048 * @n: entry to remove
1049 *
1050 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
1051 * the blob.
1052 *
1053 * This function will delete data from the reservation table and will
1054 * therefore change the indexes of some entries in the table.
1055 *
1056 * returns:
1057 *	0, on success
1058 *	-FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
1059 *		are less than n+1 reserve map entries)
1060 *	-FDT_ERR_BADMAGIC,
1061 *	-FDT_ERR_BADVERSION,
1062 *	-FDT_ERR_BADSTATE,
1063 *	-FDT_ERR_BADSTRUCTURE,
1064 *	-FDT_ERR_BADLAYOUT,
1065 *	-FDT_ERR_TRUNCATED, standard meanings
1066 */
1067int fdt_del_mem_rsv(void *fdt, int n);
1068
1069/**
1070 * fdt_set_name - change the name of a given node
1071 * @fdt: pointer to the device tree blob
1072 * @nodeoffset: structure block offset of a node
1073 * @name: name to give the node
1074 *
1075 * fdt_set_name() replaces the name (including unit address, if any)
1076 * of the given node with the given string.  NOTE: this function can't
1077 * efficiently check if the new name is unique amongst the given
1078 * node's siblings; results are undefined if this function is invoked
1079 * with a name equal to one of the given node's siblings.
1080 *
1081 * This function may insert or delete data from the blob, and will
1082 * therefore change the offsets of some existing nodes.
1083 *
1084 * returns:
1085 *	0, on success
1086 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob
1087 *		to contain the new name
1088 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1089 *	-FDT_ERR_BADMAGIC,
1090 *	-FDT_ERR_BADVERSION,
1091 *	-FDT_ERR_BADSTATE, standard meanings
1092 */
1093int fdt_set_name(void *fdt, int nodeoffset, const char *name);
1094
1095/**
1096 * fdt_setprop - create or change a property
1097 * @fdt: pointer to the device tree blob
1098 * @nodeoffset: offset of the node whose property to change
1099 * @name: name of the property to change
1100 * @val: pointer to data to set the property value to
1101 * @len: length of the property value
1102 *
1103 * fdt_setprop() sets the value of the named property in the given
1104 * node to the given value and length, creating the property if it
1105 * does not already exist.
1106 *
1107 * This function may insert or delete data from the blob, and will
1108 * therefore change the offsets of some existing nodes.
1109 *
1110 * returns:
1111 *	0, on success
1112 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1113 *		contain the new property value
1114 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1115 *	-FDT_ERR_BADLAYOUT,
1116 *	-FDT_ERR_BADMAGIC,
1117 *	-FDT_ERR_BADVERSION,
1118 *	-FDT_ERR_BADSTATE,
1119 *	-FDT_ERR_BADSTRUCTURE,
1120 *	-FDT_ERR_BADLAYOUT,
1121 *	-FDT_ERR_TRUNCATED, standard meanings
1122 */
1123int fdt_setprop(void *fdt, int nodeoffset, const char *name,
1124		const void *val, int len);
1125
1126/**
1127 * fdt_setprop_u32 - set a property to a 32-bit integer
1128 * @fdt: pointer to the device tree blob
1129 * @nodeoffset: offset of the node whose property to change
1130 * @name: name of the property to change
1131 * @val: 32-bit integer value for the property (native endian)
1132 *
1133 * fdt_setprop_u32() sets the value of the named property in the given
1134 * node to the given 32-bit integer value (converting to big-endian if
1135 * necessary), or creates a new property with that value if it does
1136 * not already exist.
1137 *
1138 * This function may insert or delete data from the blob, and will
1139 * therefore change the offsets of some existing nodes.
1140 *
1141 * returns:
1142 *	0, on success
1143 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1144 *		contain the new property value
1145 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1146 *	-FDT_ERR_BADLAYOUT,
1147 *	-FDT_ERR_BADMAGIC,
1148 *	-FDT_ERR_BADVERSION,
1149 *	-FDT_ERR_BADSTATE,
1150 *	-FDT_ERR_BADSTRUCTURE,
1151 *	-FDT_ERR_BADLAYOUT,
1152 *	-FDT_ERR_TRUNCATED, standard meanings
1153 */
1154static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
1155				  uint32_t val)
1156{
1157	val = cpu_to_fdt32(val);
1158	return fdt_setprop(fdt, nodeoffset, name, &val, sizeof(val));
1159}
1160
1161/**
1162 * fdt_setprop_u64 - set a property to a 64-bit integer
1163 * @fdt: pointer to the device tree blob
1164 * @nodeoffset: offset of the node whose property to change
1165 * @name: name of the property to change
1166 * @val: 64-bit integer value for the property (native endian)
1167 *
1168 * fdt_setprop_u64() sets the value of the named property in the given
1169 * node to the given 64-bit integer value (converting to big-endian if
1170 * necessary), or creates a new property with that value if it does
1171 * not already exist.
1172 *
1173 * This function may insert or delete data from the blob, and will
1174 * therefore change the offsets of some existing nodes.
1175 *
1176 * returns:
1177 *	0, on success
1178 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1179 *		contain the new property value
1180 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1181 *	-FDT_ERR_BADLAYOUT,
1182 *	-FDT_ERR_BADMAGIC,
1183 *	-FDT_ERR_BADVERSION,
1184 *	-FDT_ERR_BADSTATE,
1185 *	-FDT_ERR_BADSTRUCTURE,
1186 *	-FDT_ERR_BADLAYOUT,
1187 *	-FDT_ERR_TRUNCATED, standard meanings
1188 */
1189static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
1190				  uint64_t val)
1191{
1192	val = cpu_to_fdt64(val);
1193	return fdt_setprop(fdt, nodeoffset, name, &val, sizeof(val));
1194}
1195
1196/**
1197 * fdt_setprop_cell - set a property to a single cell value
1198 *
1199 * This is an alternative name for fdt_setprop_u32()
1200 */
1201static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
1202				   uint32_t val)
1203{
1204	return fdt_setprop_u32(fdt, nodeoffset, name, val);
1205}
1206
1207/**
1208 * fdt_setprop_string - set a property to a string value
1209 * @fdt: pointer to the device tree blob
1210 * @nodeoffset: offset of the node whose property to change
1211 * @name: name of the property to change
1212 * @str: string value for the property
1213 *
1214 * fdt_setprop_string() sets the value of the named property in the
1215 * given node to the given string value (using the length of the
1216 * string to determine the new length of the property), or creates a
1217 * new property with that value if it does not already exist.
1218 *
1219 * This function may insert or delete data from the blob, and will
1220 * therefore change the offsets of some existing nodes.
1221 *
1222 * returns:
1223 *	0, on success
1224 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1225 *		contain the new property value
1226 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1227 *	-FDT_ERR_BADLAYOUT,
1228 *	-FDT_ERR_BADMAGIC,
1229 *	-FDT_ERR_BADVERSION,
1230 *	-FDT_ERR_BADSTATE,
1231 *	-FDT_ERR_BADSTRUCTURE,
1232 *	-FDT_ERR_BADLAYOUT,
1233 *	-FDT_ERR_TRUNCATED, standard meanings
1234 */
1235#define fdt_setprop_string(fdt, nodeoffset, name, str) \
1236	fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1237
1238/**
1239 * fdt_appendprop - append to or create a property
1240 * @fdt: pointer to the device tree blob
1241 * @nodeoffset: offset of the node whose property to change
1242 * @name: name of the property to append to
1243 * @val: pointer to data to append to the property value
1244 * @len: length of the data to append to the property value
1245 *
1246 * fdt_appendprop() appends the value to the named property in the
1247 * given node, creating the property if it does not already exist.
1248 *
1249 * This function may insert data into the blob, and will therefore
1250 * change the offsets of some existing nodes.
1251 *
1252 * returns:
1253 *	0, on success
1254 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1255 *		contain the new property value
1256 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1257 *	-FDT_ERR_BADLAYOUT,
1258 *	-FDT_ERR_BADMAGIC,
1259 *	-FDT_ERR_BADVERSION,
1260 *	-FDT_ERR_BADSTATE,
1261 *	-FDT_ERR_BADSTRUCTURE,
1262 *	-FDT_ERR_BADLAYOUT,
1263 *	-FDT_ERR_TRUNCATED, standard meanings
1264 */
1265int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
1266		   const void *val, int len);
1267
1268/**
1269 * fdt_appendprop_u32 - append a 32-bit integer value to a property
1270 * @fdt: pointer to the device tree blob
1271 * @nodeoffset: offset of the node whose property to change
1272 * @name: name of the property to change
1273 * @val: 32-bit integer value to append to the property (native endian)
1274 *
1275 * fdt_appendprop_u32() appends the given 32-bit integer value
1276 * (converting to big-endian if necessary) to the value of the named
1277 * property in the given node, or creates a new property with that
1278 * value if it does not already exist.
1279 *
1280 * This function may insert data into the blob, and will therefore
1281 * change the offsets of some existing nodes.
1282 *
1283 * returns:
1284 *	0, on success
1285 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1286 *		contain the new property value
1287 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1288 *	-FDT_ERR_BADLAYOUT,
1289 *	-FDT_ERR_BADMAGIC,
1290 *	-FDT_ERR_BADVERSION,
1291 *	-FDT_ERR_BADSTATE,
1292 *	-FDT_ERR_BADSTRUCTURE,
1293 *	-FDT_ERR_BADLAYOUT,
1294 *	-FDT_ERR_TRUNCATED, standard meanings
1295 */
1296static inline int fdt_appendprop_u32(void *fdt, int nodeoffset,
1297				     const char *name, uint32_t val)
1298{
1299	val = cpu_to_fdt32(val);
1300	return fdt_appendprop(fdt, nodeoffset, name, &val, sizeof(val));
1301}
1302
1303/**
1304 * fdt_appendprop_u64 - append a 64-bit integer value to a property
1305 * @fdt: pointer to the device tree blob
1306 * @nodeoffset: offset of the node whose property to change
1307 * @name: name of the property to change
1308 * @val: 64-bit integer value to append to the property (native endian)
1309 *
1310 * fdt_appendprop_u64() appends the given 64-bit integer value
1311 * (converting to big-endian if necessary) to the value of the named
1312 * property in the given node, or creates a new property with that
1313 * value if it does not already exist.
1314 *
1315 * This function may insert data into the blob, and will therefore
1316 * change the offsets of some existing nodes.
1317 *
1318 * returns:
1319 *	0, on success
1320 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1321 *		contain the new property value
1322 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1323 *	-FDT_ERR_BADLAYOUT,
1324 *	-FDT_ERR_BADMAGIC,
1325 *	-FDT_ERR_BADVERSION,
1326 *	-FDT_ERR_BADSTATE,
1327 *	-FDT_ERR_BADSTRUCTURE,
1328 *	-FDT_ERR_BADLAYOUT,
1329 *	-FDT_ERR_TRUNCATED, standard meanings
1330 */
1331static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
1332				     const char *name, uint64_t val)
1333{
1334	val = cpu_to_fdt64(val);
1335	return fdt_appendprop(fdt, nodeoffset, name, &val, sizeof(val));
1336}
1337
1338/**
1339 * fdt_appendprop_cell - append a single cell value to a property
1340 *
1341 * This is an alternative name for fdt_appendprop_u32()
1342 */
1343static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
1344				      const char *name, uint32_t val)
1345{
1346	return fdt_appendprop_u32(fdt, nodeoffset, name, val);
1347}
1348
1349/**
1350 * fdt_appendprop_string - append a string to a property
1351 * @fdt: pointer to the device tree blob
1352 * @nodeoffset: offset of the node whose property to change
1353 * @name: name of the property to change
1354 * @str: string value to append to the property
1355 *
1356 * fdt_appendprop_string() appends the given string to the value of
1357 * the named property in the given node, or creates a new property
1358 * with that value if it does not already exist.
1359 *
1360 * This function may insert data into the blob, and will therefore
1361 * change the offsets of some existing nodes.
1362 *
1363 * returns:
1364 *	0, on success
1365 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1366 *		contain the new property value
1367 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1368 *	-FDT_ERR_BADLAYOUT,
1369 *	-FDT_ERR_BADMAGIC,
1370 *	-FDT_ERR_BADVERSION,
1371 *	-FDT_ERR_BADSTATE,
1372 *	-FDT_ERR_BADSTRUCTURE,
1373 *	-FDT_ERR_BADLAYOUT,
1374 *	-FDT_ERR_TRUNCATED, standard meanings
1375 */
1376#define fdt_appendprop_string(fdt, nodeoffset, name, str) \
1377	fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1378
1379/**
1380 * fdt_delprop - delete a property
1381 * @fdt: pointer to the device tree blob
1382 * @nodeoffset: offset of the node whose property to nop
1383 * @name: name of the property to nop
1384 *
1385 * fdt_del_property() will delete the given property.
1386 *
1387 * This function will delete data from the blob, and will therefore
1388 * change the offsets of some existing nodes.
1389 *
1390 * returns:
1391 *	0, on success
1392 *	-FDT_ERR_NOTFOUND, node does not have the named property
1393 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1394 *	-FDT_ERR_BADLAYOUT,
1395 *	-FDT_ERR_BADMAGIC,
1396 *	-FDT_ERR_BADVERSION,
1397 *	-FDT_ERR_BADSTATE,
1398 *	-FDT_ERR_BADSTRUCTURE,
1399 *	-FDT_ERR_TRUNCATED, standard meanings
1400 */
1401int fdt_delprop(void *fdt, int nodeoffset, const char *name);
1402
1403/**
1404 * fdt_add_subnode_namelen - creates a new node based on substring
1405 * @fdt: pointer to the device tree blob
1406 * @parentoffset: structure block offset of a node
1407 * @name: name of the subnode to locate
1408 * @namelen: number of characters of name to consider
1409 *
1410 * Identical to fdt_add_subnode(), but use only the first namelen
1411 * characters of name as the name of the new node.  This is useful for
1412 * creating subnodes based on a portion of a larger string, such as a
1413 * full path.
1414 */
1415int fdt_add_subnode_namelen(void *fdt, int parentoffset,
1416			    const char *name, int namelen);
1417
1418/**
1419 * fdt_add_subnode - creates a new node
1420 * @fdt: pointer to the device tree blob
1421 * @parentoffset: structure block offset of a node
1422 * @name: name of the subnode to locate
1423 *
1424 * fdt_add_subnode() creates a new node as a subnode of the node at
1425 * structure block offset parentoffset, with the given name (which
1426 * should include the unit address, if any).
1427 *
1428 * This function will insert data into the blob, and will therefore
1429 * change the offsets of some existing nodes.
1430
1431 * returns:
1432 *	structure block offset of the created nodeequested subnode (>=0), on success
1433 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
1434 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
1435 *	-FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
1436 *		the given name
1437 *	-FDT_ERR_NOSPACE, if there is insufficient free space in the
1438 *		blob to contain the new node
1439 *	-FDT_ERR_NOSPACE
1440 *	-FDT_ERR_BADLAYOUT
1441 *      -FDT_ERR_BADMAGIC,
1442 *	-FDT_ERR_BADVERSION,
1443 *	-FDT_ERR_BADSTATE,
1444 *	-FDT_ERR_BADSTRUCTURE,
1445 *	-FDT_ERR_TRUNCATED, standard meanings.
1446 */
1447int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
1448
1449/**
1450 * fdt_del_node - delete a node (subtree)
1451 * @fdt: pointer to the device tree blob
1452 * @nodeoffset: offset of the node to nop
1453 *
1454 * fdt_del_node() will remove the given node, including all its
1455 * subnodes if any, from the blob.
1456 *
1457 * This function will delete data from the blob, and will therefore
1458 * change the offsets of some existing nodes.
1459 *
1460 * returns:
1461 *	0, on success
1462 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1463 *	-FDT_ERR_BADLAYOUT,
1464 *	-FDT_ERR_BADMAGIC,
1465 *	-FDT_ERR_BADVERSION,
1466 *	-FDT_ERR_BADSTATE,
1467 *	-FDT_ERR_BADSTRUCTURE,
1468 *	-FDT_ERR_TRUNCATED, standard meanings
1469 */
1470int fdt_del_node(void *fdt, int nodeoffset);
1471
1472/**********************************************************************/
1473/* Debugging / informational functions                                */
1474/**********************************************************************/
1475
1476const char *fdt_strerror(int errval);
1477
1478#endif /* _LIBFDT_H */