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	 * This can be caused either by an invalid phandle property
84	 * length, or the phandle value was either 0 or -1, which are
85	 * not permitted. */
86#define FDT_ERR_BADSTATE	7
87	/* FDT_ERR_BADSTATE: Function was passed an incomplete device
88	 * tree created by the sequential-write functions, which is
89	 * not sufficiently complete for the requested operation. */
90
91/* Error codes: codes for bad device tree blobs */
92#define FDT_ERR_TRUNCATED	8
93	/* FDT_ERR_TRUNCATED: Structure block of the given device tree
94	 * ends without an FDT_END tag. */
95#define FDT_ERR_BADMAGIC	9
96	/* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
97	 * device tree at all - it is missing the flattened device
98	 * tree magic number. */
99#define FDT_ERR_BADVERSION	10
100	/* FDT_ERR_BADVERSION: Given device tree has a version which
101	 * can't be handled by the requested operation.  For
102	 * read-write functions, this may mean that fdt_open_into() is
103	 * required to convert the tree to the expected version. */
104#define FDT_ERR_BADSTRUCTURE	11
105	/* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt
106	 * structure block or other serious error (e.g. misnested
107	 * nodes, or subnodes preceding properties). */
108#define FDT_ERR_BADLAYOUT	12
109	/* FDT_ERR_BADLAYOUT: For read-write functions, the given
110	 * device tree has it's sub-blocks in an order that the
111	 * function can't handle (memory reserve map, then structure,
112	 * then strings).  Use fdt_open_into() to reorganize the tree
113	 * into a form suitable for the read-write operations. */
114
115/* "Can't happen" error indicating a bug in libfdt */
116#define FDT_ERR_INTERNAL	13
117	/* FDT_ERR_INTERNAL: libfdt has failed an internal assertion.
118	 * Should never be returned, if it is, it indicates a bug in
119	 * libfdt itself. */
120
121/* Errors in device tree content */
122#define FDT_ERR_BADNCELLS	14
123	/* FDT_ERR_BADNCELLS: Device tree has a #address-cells, #size-cells
124	 * or similar property with a bad format or value */
125
126#define FDT_ERR_BADVALUE	15
127	/* FDT_ERR_BADVALUE: Device tree has a property with an unexpected
128	 * value. For example: a property expected to contain a string list
129	 * is not NUL-terminated within the length of its value. */
130
131#define FDT_ERR_BADOVERLAY	16
132	/* FDT_ERR_BADOVERLAY: The device tree overlay, while
133	 * correctly structured, cannot be applied due to some
134	 * unexpected or missing value, property or node. */
135
136#define FDT_ERR_NOPHANDLES	17
137	/* FDT_ERR_NOPHANDLES: The device tree doesn't have any
138	 * phandle available anymore without causing an overflow */
139
140#define FDT_ERR_MAX		17
141
142/**********************************************************************/
143/* Low-level functions (you probably don't need these)                */
144/**********************************************************************/
145
146const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen);
147static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
148{
149	return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
150}
151
152uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
153
154/**********************************************************************/
155/* Traversal functions                                                */
156/**********************************************************************/
157
158int fdt_next_node(const void *fdt, int offset, int *depth);
159
160/**
161 * fdt_first_subnode() - get offset of first direct subnode
162 *
163 * @fdt:	FDT blob
164 * @offset:	Offset of node to check
165 * @return offset of first subnode, or -FDT_ERR_NOTFOUND if there is none
166 */
167int fdt_first_subnode(const void *fdt, int offset);
168
169/**
170 * fdt_next_subnode() - get offset of next direct subnode
171 *
172 * After first calling fdt_first_subnode(), call this function repeatedly to
173 * get direct subnodes of a parent node.
174 *
175 * @fdt:	FDT blob
176 * @offset:	Offset of previous subnode
177 * @return offset of next subnode, or -FDT_ERR_NOTFOUND if there are no more
178 * subnodes
179 */
180int fdt_next_subnode(const void *fdt, int offset);
181
182/**
183 * fdt_for_each_subnode - iterate over all subnodes of a parent
184 *
185 * @node:	child node (int, lvalue)
186 * @fdt:	FDT blob (const void *)
187 * @parent:	parent node (int)
188 *
189 * This is actually a wrapper around a for loop and would be used like so:
190 *
191 *	fdt_for_each_subnode(node, fdt, parent) {
192 *		Use node
193 *		...
194 *	}
195 *
196 *	if ((node < 0) && (node != -FDT_ERR_NOT_FOUND)) {
197 *		Error handling
198 *	}
199 *
200 * Note that this is implemented as a macro and @node is used as
201 * iterator in the loop. The parent variable be constant or even a
202 * literal.
203 *
204 */
205#define fdt_for_each_subnode(node, fdt, parent)		\
206	for (node = fdt_first_subnode(fdt, parent);	\
207	     node >= 0;					\
208	     node = fdt_next_subnode(fdt, node))
209
210/**********************************************************************/
211/* General functions                                                  */
212/**********************************************************************/
213
214#define fdt_get_header(fdt, field) \
215	(fdt32_to_cpu(((const struct fdt_header *)(fdt))->field))
216#define fdt_magic(fdt)			(fdt_get_header(fdt, magic))
217#define fdt_totalsize(fdt)		(fdt_get_header(fdt, totalsize))
218#define fdt_off_dt_struct(fdt)		(fdt_get_header(fdt, off_dt_struct))
219#define fdt_off_dt_strings(fdt)		(fdt_get_header(fdt, off_dt_strings))
220#define fdt_off_mem_rsvmap(fdt)		(fdt_get_header(fdt, off_mem_rsvmap))
221#define fdt_version(fdt)		(fdt_get_header(fdt, version))
222#define fdt_last_comp_version(fdt)	(fdt_get_header(fdt, last_comp_version))
223#define fdt_boot_cpuid_phys(fdt)	(fdt_get_header(fdt, boot_cpuid_phys))
224#define fdt_size_dt_strings(fdt)	(fdt_get_header(fdt, size_dt_strings))
225#define fdt_size_dt_struct(fdt)		(fdt_get_header(fdt, size_dt_struct))
226
227#define __fdt_set_hdr(name) \
228	static inline void fdt_set_##name(void *fdt, uint32_t val) \
229	{ \
230		struct fdt_header *fdth = (struct fdt_header *)fdt; \
231		fdth->name = cpu_to_fdt32(val); \
232	}
233__fdt_set_hdr(magic);
234__fdt_set_hdr(totalsize);
235__fdt_set_hdr(off_dt_struct);
236__fdt_set_hdr(off_dt_strings);
237__fdt_set_hdr(off_mem_rsvmap);
238__fdt_set_hdr(version);
239__fdt_set_hdr(last_comp_version);
240__fdt_set_hdr(boot_cpuid_phys);
241__fdt_set_hdr(size_dt_strings);
242__fdt_set_hdr(size_dt_struct);
243#undef __fdt_set_hdr
244
245/**
246 * fdt_check_header - sanity check a device tree or possible device tree
247 * @fdt: pointer to data which might be a flattened device tree
248 *
249 * fdt_check_header() checks that the given buffer contains what
250 * appears to be a flattened device tree with sane information in its
251 * header.
252 *
253 * returns:
254 *     0, if the buffer appears to contain a valid device tree
255 *     -FDT_ERR_BADMAGIC,
256 *     -FDT_ERR_BADVERSION,
257 *     -FDT_ERR_BADSTATE, standard meanings, as above
258 */
259int fdt_check_header(const void *fdt);
260
261/**
262 * fdt_move - move a device tree around in memory
263 * @fdt: pointer to the device tree to move
264 * @buf: pointer to memory where the device is to be moved
265 * @bufsize: size of the memory space at buf
266 *
267 * fdt_move() relocates, if possible, the device tree blob located at
268 * fdt to the buffer at buf of size bufsize.  The buffer may overlap
269 * with the existing device tree blob at fdt.  Therefore,
270 *     fdt_move(fdt, fdt, fdt_totalsize(fdt))
271 * should always succeed.
272 *
273 * returns:
274 *     0, on success
275 *     -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
276 *     -FDT_ERR_BADMAGIC,
277 *     -FDT_ERR_BADVERSION,
278 *     -FDT_ERR_BADSTATE, standard meanings
279 */
280int fdt_move(const void *fdt, void *buf, int bufsize);
281
282/**********************************************************************/
283/* Read-only functions                                                */
284/**********************************************************************/
285
286/**
287 * fdt_string - retrieve a string from the strings block of a device tree
288 * @fdt: pointer to the device tree blob
289 * @stroffset: offset of the string within the strings block (native endian)
290 *
291 * fdt_string() retrieves a pointer to a single string from the
292 * strings block of the device tree blob at fdt.
293 *
294 * returns:
295 *     a pointer to the string, on success
296 *     NULL, if stroffset is out of bounds
297 */
298const char *fdt_string(const void *fdt, int stroffset);
299
300/**
301 * fdt_get_max_phandle - retrieves the highest phandle in a tree
302 * @fdt: pointer to the device tree blob
303 *
304 * fdt_get_max_phandle retrieves the highest phandle in the given
305 * device tree. This will ignore badly formatted phandles, or phandles
306 * with a value of 0 or -1.
307 *
308 * returns:
309 *      the highest phandle on success
310 *      0, if no phandle was found in the device tree
311 *      -1, if an error occurred
312 */
313uint32_t fdt_get_max_phandle(const void *fdt);
314
315/**
316 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
317 * @fdt: pointer to the device tree blob
318 *
319 * Returns the number of entries in the device tree blob's memory
320 * reservation map.  This does not include the terminating 0,0 entry
321 * or any other (0,0) entries reserved for expansion.
322 *
323 * returns:
324 *     the number of entries
325 */
326int fdt_num_mem_rsv(const void *fdt);
327
328/**
329 * fdt_get_mem_rsv - retrieve one memory reserve map entry
330 * @fdt: pointer to the device tree blob
331 * @address, @size: pointers to 64-bit variables
332 *
333 * On success, *address and *size will contain the address and size of
334 * the n-th reserve map entry from the device tree blob, in
335 * native-endian format.
336 *
337 * returns:
338 *     0, on success
339 *     -FDT_ERR_BADMAGIC,
340 *     -FDT_ERR_BADVERSION,
341 *     -FDT_ERR_BADSTATE, standard meanings
342 */
343int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
344
345/**
346 * fdt_subnode_offset_namelen - find a subnode based on substring
347 * @fdt: pointer to the device tree blob
348 * @parentoffset: structure block offset of a node
349 * @name: name of the subnode to locate
350 * @namelen: number of characters of name to consider
351 *
352 * Identical to fdt_subnode_offset(), but only examine the first
353 * namelen characters of name for matching the subnode name.  This is
354 * useful for finding subnodes based on a portion of a larger string,
355 * such as a full path.
356 */
357int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
358			       const char *name, int namelen);
359/**
360 * fdt_subnode_offset - find a subnode of a given node
361 * @fdt: pointer to the device tree blob
362 * @parentoffset: structure block offset of a node
363 * @name: name of the subnode to locate
364 *
365 * fdt_subnode_offset() finds a subnode of the node at structure block
366 * offset parentoffset with the given name.  name may include a unit
367 * address, in which case fdt_subnode_offset() will find the subnode
368 * with that unit address, or the unit address may be omitted, in
369 * which case fdt_subnode_offset() will find an arbitrary subnode
370 * whose name excluding unit address matches the given name.
371 *
372 * returns:
373 *	structure block offset of the requested subnode (>=0), on success
374 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
375 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
376 *		tag
377 *	-FDT_ERR_BADMAGIC,
378 *	-FDT_ERR_BADVERSION,
379 *	-FDT_ERR_BADSTATE,
380 *	-FDT_ERR_BADSTRUCTURE,
381 *	-FDT_ERR_TRUNCATED, standard meanings.
382 */
383int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
384
385/**
386 * fdt_path_offset_namelen - find a tree node by its full path
387 * @fdt: pointer to the device tree blob
388 * @path: full path of the node to locate
389 * @namelen: number of characters of path to consider
390 *
391 * Identical to fdt_path_offset(), but only consider the first namelen
392 * characters of path as the path name.
393 */
394int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen);
395
396/**
397 * fdt_path_offset - find a tree node by its full path
398 * @fdt: pointer to the device tree blob
399 * @path: full path of the node to locate
400 *
401 * fdt_path_offset() finds a node of a given path in the device tree.
402 * Each path component may omit the unit address portion, but the
403 * results of this are undefined if any such path component is
404 * ambiguous (that is if there are multiple nodes at the relevant
405 * level matching the given component, differentiated only by unit
406 * address).
407 *
408 * returns:
409 *	structure block offset of the node with the requested path (>=0), on
410 *		success
411 *	-FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
412 *	-FDT_ERR_NOTFOUND, if the requested node does not exist
413 *      -FDT_ERR_BADMAGIC,
414 *	-FDT_ERR_BADVERSION,
415 *	-FDT_ERR_BADSTATE,
416 *	-FDT_ERR_BADSTRUCTURE,
417 *	-FDT_ERR_TRUNCATED, standard meanings.
418 */
419int fdt_path_offset(const void *fdt, const char *path);
420
421/**
422 * fdt_get_name - retrieve the name of a given node
423 * @fdt: pointer to the device tree blob
424 * @nodeoffset: structure block offset of the starting node
425 * @lenp: pointer to an integer variable (will be overwritten) or NULL
426 *
427 * fdt_get_name() retrieves the name (including unit address) of the
428 * device tree node at structure block offset nodeoffset.  If lenp is
429 * non-NULL, the length of this name is also returned, in the integer
430 * pointed to by lenp.
431 *
432 * returns:
433 *	pointer to the node's name, on success
434 *		If lenp is non-NULL, *lenp contains the length of that name
435 *			(>=0)
436 *	NULL, on error
437 *		if lenp is non-NULL *lenp contains an error code (<0):
438 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
439 *			tag
440 *		-FDT_ERR_BADMAGIC,
441 *		-FDT_ERR_BADVERSION,
442 *		-FDT_ERR_BADSTATE, standard meanings
443 */
444const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
445
446/**
447 * fdt_first_property_offset - find the offset of a node's first property
448 * @fdt: pointer to the device tree blob
449 * @nodeoffset: structure block offset of a node
450 *
451 * fdt_first_property_offset() finds the first property of the node at
452 * the given structure block offset.
453 *
454 * returns:
455 *	structure block offset of the property (>=0), on success
456 *	-FDT_ERR_NOTFOUND, if the requested node has no properties
457 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
458 *      -FDT_ERR_BADMAGIC,
459 *	-FDT_ERR_BADVERSION,
460 *	-FDT_ERR_BADSTATE,
461 *	-FDT_ERR_BADSTRUCTURE,
462 *	-FDT_ERR_TRUNCATED, standard meanings.
463 */
464int fdt_first_property_offset(const void *fdt, int nodeoffset);
465
466/**
467 * fdt_next_property_offset - step through a node's properties
468 * @fdt: pointer to the device tree blob
469 * @offset: structure block offset of a property
470 *
471 * fdt_next_property_offset() finds the property immediately after the
472 * one at the given structure block offset.  This will be a property
473 * of the same node as the given property.
474 *
475 * returns:
476 *	structure block offset of the next property (>=0), on success
477 *	-FDT_ERR_NOTFOUND, if the given property is the last in its node
478 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag
479 *      -FDT_ERR_BADMAGIC,
480 *	-FDT_ERR_BADVERSION,
481 *	-FDT_ERR_BADSTATE,
482 *	-FDT_ERR_BADSTRUCTURE,
483 *	-FDT_ERR_TRUNCATED, standard meanings.
484 */
485int fdt_next_property_offset(const void *fdt, int offset);
486
487/**
488 * fdt_for_each_property_offset - iterate over all properties of a node
489 *
490 * @property_offset:	property offset (int, lvalue)
491 * @fdt:		FDT blob (const void *)
492 * @node:		node offset (int)
493 *
494 * This is actually a wrapper around a for loop and would be used like so:
495 *
496 *	fdt_for_each_property_offset(property, fdt, node) {
497 *		Use property
498 *		...
499 *	}
500 *
501 *	if ((property < 0) && (property != -FDT_ERR_NOT_FOUND)) {
502 *		Error handling
503 *	}
504 *
505 * Note that this is implemented as a macro and property is used as
506 * iterator in the loop. The node variable can be constant or even a
507 * literal.
508 */
509#define fdt_for_each_property_offset(property, fdt, node)	\
510	for (property = fdt_first_property_offset(fdt, node);	\
511	     property >= 0;					\
512	     property = fdt_next_property_offset(fdt, property))
513
514/**
515 * fdt_get_property_by_offset - retrieve the property at a given offset
516 * @fdt: pointer to the device tree blob
517 * @offset: offset of the property to retrieve
518 * @lenp: pointer to an integer variable (will be overwritten) or NULL
519 *
520 * fdt_get_property_by_offset() retrieves a pointer to the
521 * fdt_property structure within the device tree blob at the given
522 * offset.  If lenp is non-NULL, the length of the property value is
523 * also returned, in the integer pointed to by lenp.
524 *
525 * returns:
526 *	pointer to the structure representing the property
527 *		if lenp is non-NULL, *lenp contains the length of the property
528 *		value (>=0)
529 *	NULL, on error
530 *		if lenp is non-NULL, *lenp contains an error code (<0):
531 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
532 *		-FDT_ERR_BADMAGIC,
533 *		-FDT_ERR_BADVERSION,
534 *		-FDT_ERR_BADSTATE,
535 *		-FDT_ERR_BADSTRUCTURE,
536 *		-FDT_ERR_TRUNCATED, standard meanings
537 */
538const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
539						      int offset,
540						      int *lenp);
541
542/**
543 * fdt_get_property_namelen - find a property based on substring
544 * @fdt: pointer to the device tree blob
545 * @nodeoffset: offset of the node whose property to find
546 * @name: name of the property to find
547 * @namelen: number of characters of name to consider
548 * @lenp: pointer to an integer variable (will be overwritten) or NULL
549 *
550 * Identical to fdt_get_property(), but only examine the first namelen
551 * characters of name for matching the property name.
552 */
553const struct fdt_property *fdt_get_property_namelen(const void *fdt,
554						    int nodeoffset,
555						    const char *name,
556						    int namelen, int *lenp);
557
558/**
559 * fdt_get_property - find a given property in a given node
560 * @fdt: pointer to the device tree blob
561 * @nodeoffset: offset of the node whose property to find
562 * @name: name of the property to find
563 * @lenp: pointer to an integer variable (will be overwritten) or NULL
564 *
565 * fdt_get_property() retrieves a pointer to the fdt_property
566 * structure within the device tree blob corresponding to the property
567 * named 'name' of the node at offset nodeoffset.  If lenp is
568 * non-NULL, the length of the property value is also returned, in the
569 * integer pointed to by lenp.
570 *
571 * returns:
572 *	pointer to the structure representing the property
573 *		if lenp is non-NULL, *lenp contains the length of the property
574 *		value (>=0)
575 *	NULL, on error
576 *		if lenp is non-NULL, *lenp contains an error code (<0):
577 *		-FDT_ERR_NOTFOUND, node does not have named property
578 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
579 *			tag
580 *		-FDT_ERR_BADMAGIC,
581 *		-FDT_ERR_BADVERSION,
582 *		-FDT_ERR_BADSTATE,
583 *		-FDT_ERR_BADSTRUCTURE,
584 *		-FDT_ERR_TRUNCATED, standard meanings
585 */
586const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
587					    const char *name, int *lenp);
588static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
589						      const char *name,
590						      int *lenp)
591{
592	return (struct fdt_property *)(uintptr_t)
593		fdt_get_property(fdt, nodeoffset, name, lenp);
594}
595
596/**
597 * fdt_getprop_by_offset - retrieve the value of a property at a given offset
598 * @fdt: pointer to the device tree blob
599 * @ffset: offset of the property to read
600 * @namep: pointer to a string variable (will be overwritten) or NULL
601 * @lenp: pointer to an integer variable (will be overwritten) or NULL
602 *
603 * fdt_getprop_by_offset() retrieves a pointer to the value of the
604 * property at structure block offset 'offset' (this will be a pointer
605 * to within the device blob itself, not a copy of the value).  If
606 * lenp is non-NULL, the length of the property value is also
607 * returned, in the integer pointed to by lenp.  If namep is non-NULL,
608 * the property's namne will also be returned in the char * pointed to
609 * by namep (this will be a pointer to within the device tree's string
610 * block, not a new copy of the name).
611 *
612 * returns:
613 *	pointer to the property's value
614 *		if lenp is non-NULL, *lenp contains the length of the property
615 *		value (>=0)
616 *		if namep is non-NULL *namep contiains a pointer to the property
617 *		name.
618 *	NULL, on error
619 *		if lenp is non-NULL, *lenp contains an error code (<0):
620 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
621 *		-FDT_ERR_BADMAGIC,
622 *		-FDT_ERR_BADVERSION,
623 *		-FDT_ERR_BADSTATE,
624 *		-FDT_ERR_BADSTRUCTURE,
625 *		-FDT_ERR_TRUNCATED, standard meanings
626 */
627const void *fdt_getprop_by_offset(const void *fdt, int offset,
628				  const char **namep, int *lenp);
629
630/**
631 * fdt_getprop_namelen - get property value based on substring
632 * @fdt: pointer to the device tree blob
633 * @nodeoffset: offset of the node whose property to find
634 * @name: name of the property to find
635 * @namelen: number of characters of name to consider
636 * @lenp: pointer to an integer variable (will be overwritten) or NULL
637 *
638 * Identical to fdt_getprop(), but only examine the first namelen
639 * characters of name for matching the property name.
640 */
641const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
642				const char *name, int namelen, int *lenp);
643static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset,
644					  const char *name, int namelen,
645					  int *lenp)
646{
647	return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name,
648						      namelen, lenp);
649}
650
651/**
652 * fdt_getprop - retrieve the value of a given property
653 * @fdt: pointer to the device tree blob
654 * @nodeoffset: offset of the node whose property to find
655 * @name: name of the property to find
656 * @lenp: pointer to an integer variable (will be overwritten) or NULL
657 *
658 * fdt_getprop() retrieves a pointer to the value of the property
659 * named 'name' of the node at offset nodeoffset (this will be a
660 * pointer to within the device blob itself, not a copy of the value).
661 * If lenp is non-NULL, the length of the property value is also
662 * returned, in the integer pointed to by lenp.
663 *
664 * returns:
665 *	pointer to the property's value
666 *		if lenp is non-NULL, *lenp contains the length of the property
667 *		value (>=0)
668 *	NULL, on error
669 *		if lenp is non-NULL, *lenp contains an error code (<0):
670 *		-FDT_ERR_NOTFOUND, node does not have named property
671 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
672 *			tag
673 *		-FDT_ERR_BADMAGIC,
674 *		-FDT_ERR_BADVERSION,
675 *		-FDT_ERR_BADSTATE,
676 *		-FDT_ERR_BADSTRUCTURE,
677 *		-FDT_ERR_TRUNCATED, standard meanings
678 */
679const void *fdt_getprop(const void *fdt, int nodeoffset,
680			const char *name, int *lenp);
681static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
682				  const char *name, int *lenp)
683{
684	return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
685}
686
687/**
688 * fdt_get_phandle - retrieve the phandle of a given node
689 * @fdt: pointer to the device tree blob
690 * @nodeoffset: structure block offset of the node
691 *
692 * fdt_get_phandle() retrieves the phandle of the device tree node at
693 * structure block offset nodeoffset.
694 *
695 * returns:
696 *	the phandle of the node at nodeoffset, on success (!= 0, != -1)
697 *	0, if the node has no phandle, or another error occurs
698 */
699uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
700
701/**
702 * fdt_get_alias_namelen - get alias based on substring
703 * @fdt: pointer to the device tree blob
704 * @name: name of the alias th look up
705 * @namelen: number of characters of name to consider
706 *
707 * Identical to fdt_get_alias(), but only examine the first namelen
708 * characters of name for matching the alias name.
709 */
710const char *fdt_get_alias_namelen(const void *fdt,
711				  const char *name, int namelen);
712
713/**
714 * fdt_get_alias - retrieve the path referenced by a given alias
715 * @fdt: pointer to the device tree blob
716 * @name: name of the alias th look up
717 *
718 * fdt_get_alias() retrieves the value of a given alias.  That is, the
719 * value of the property named 'name' in the node /aliases.
720 *
721 * returns:
722 *	a pointer to the expansion of the alias named 'name', if it exists
723 *	NULL, if the given alias or the /aliases node does not exist
724 */
725const char *fdt_get_alias(const void *fdt, const char *name);
726
727/**
728 * fdt_get_path - determine the full path of a node
729 * @fdt: pointer to the device tree blob
730 * @nodeoffset: offset of the node whose path to find
731 * @buf: character buffer to contain the returned path (will be overwritten)
732 * @buflen: size of the character buffer at buf
733 *
734 * fdt_get_path() computes the full path of the node at offset
735 * nodeoffset, and records that path in the buffer at buf.
736 *
737 * NOTE: This function is expensive, as it must scan the device tree
738 * structure from the start to nodeoffset.
739 *
740 * returns:
741 *	0, on success
742 *		buf contains the absolute path of the node at
743 *		nodeoffset, as a NUL-terminated string.
744 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
745 *	-FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
746 *		characters and will not fit in the given buffer.
747 *	-FDT_ERR_BADMAGIC,
748 *	-FDT_ERR_BADVERSION,
749 *	-FDT_ERR_BADSTATE,
750 *	-FDT_ERR_BADSTRUCTURE, standard meanings
751 */
752int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
753
754/**
755 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
756 * @fdt: pointer to the device tree blob
757 * @nodeoffset: offset of the node whose parent to find
758 * @supernodedepth: depth of the ancestor to find
759 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
760 *
761 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
762 * at a specific depth from the root (where the root itself has depth
763 * 0, its immediate subnodes depth 1 and so forth).  So
764 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
765 * will always return 0, the offset of the root node.  If the node at
766 * nodeoffset has depth D, then:
767 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
768 * will return nodeoffset itself.
769 *
770 * NOTE: This function is expensive, as it must scan the device tree
771 * structure from the start to nodeoffset.
772 *
773 * returns:
774 *	structure block offset of the node at node offset's ancestor
775 *		of depth supernodedepth (>=0), on success
776 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
777 *	-FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of
778 *		nodeoffset
779 *	-FDT_ERR_BADMAGIC,
780 *	-FDT_ERR_BADVERSION,
781 *	-FDT_ERR_BADSTATE,
782 *	-FDT_ERR_BADSTRUCTURE, standard meanings
783 */
784int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
785				 int supernodedepth, int *nodedepth);
786
787/**
788 * fdt_node_depth - find the depth of a given node
789 * @fdt: pointer to the device tree blob
790 * @nodeoffset: offset of the node whose parent to find
791 *
792 * fdt_node_depth() finds the depth of a given node.  The root node
793 * has depth 0, its immediate subnodes depth 1 and so forth.
794 *
795 * NOTE: This function is expensive, as it must scan the device tree
796 * structure from the start to nodeoffset.
797 *
798 * returns:
799 *	depth of the node at nodeoffset (>=0), on success
800 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
801 *	-FDT_ERR_BADMAGIC,
802 *	-FDT_ERR_BADVERSION,
803 *	-FDT_ERR_BADSTATE,
804 *	-FDT_ERR_BADSTRUCTURE, standard meanings
805 */
806int fdt_node_depth(const void *fdt, int nodeoffset);
807
808/**
809 * fdt_parent_offset - find the parent of a given node
810 * @fdt: pointer to the device tree blob
811 * @nodeoffset: offset of the node whose parent to find
812 *
813 * fdt_parent_offset() locates the parent node of a given node (that
814 * is, it finds the offset of the node which contains the node at
815 * nodeoffset as a subnode).
816 *
817 * NOTE: This function is expensive, as it must scan the device tree
818 * structure from the start to nodeoffset, *twice*.
819 *
820 * returns:
821 *	structure block offset of the parent of the node at nodeoffset
822 *		(>=0), on success
823 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
824 *	-FDT_ERR_BADMAGIC,
825 *	-FDT_ERR_BADVERSION,
826 *	-FDT_ERR_BADSTATE,
827 *	-FDT_ERR_BADSTRUCTURE, standard meanings
828 */
829int fdt_parent_offset(const void *fdt, int nodeoffset);
830
831/**
832 * fdt_node_offset_by_prop_value - find nodes with a given property value
833 * @fdt: pointer to the device tree blob
834 * @startoffset: only find nodes after this offset
835 * @propname: property name to check
836 * @propval: property value to search for
837 * @proplen: length of the value in propval
838 *
839 * fdt_node_offset_by_prop_value() returns the offset of the first
840 * node after startoffset, which has a property named propname whose
841 * value is of length proplen and has value equal to propval; or if
842 * startoffset is -1, the very first such node in the tree.
843 *
844 * To iterate through all nodes matching the criterion, the following
845 * idiom can be used:
846 *	offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
847 *					       propval, proplen);
848 *	while (offset != -FDT_ERR_NOTFOUND) {
849 *		// other code here
850 *		offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
851 *						       propval, proplen);
852 *	}
853 *
854 * Note the -1 in the first call to the function, if 0 is used here
855 * instead, the function will never locate the root node, even if it
856 * matches the criterion.
857 *
858 * returns:
859 *	structure block offset of the located node (>= 0, >startoffset),
860 *		 on success
861 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
862 *		tree after startoffset
863 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
864 *	-FDT_ERR_BADMAGIC,
865 *	-FDT_ERR_BADVERSION,
866 *	-FDT_ERR_BADSTATE,
867 *	-FDT_ERR_BADSTRUCTURE, standard meanings
868 */
869int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
870				  const char *propname,
871				  const void *propval, int proplen);
872
873/**
874 * fdt_node_offset_by_phandle - find the node with a given phandle
875 * @fdt: pointer to the device tree blob
876 * @phandle: phandle value
877 *
878 * fdt_node_offset_by_phandle() returns the offset of the node
879 * which has the given phandle value.  If there is more than one node
880 * in the tree with the given phandle (an invalid tree), results are
881 * undefined.
882 *
883 * returns:
884 *	structure block offset of the located node (>= 0), on success
885 *	-FDT_ERR_NOTFOUND, no node with that phandle exists
886 *	-FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
887 *	-FDT_ERR_BADMAGIC,
888 *	-FDT_ERR_BADVERSION,
889 *	-FDT_ERR_BADSTATE,
890 *	-FDT_ERR_BADSTRUCTURE, standard meanings
891 */
892int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
893
894/**
895 * fdt_node_check_compatible: check a node's compatible property
896 * @fdt: pointer to the device tree blob
897 * @nodeoffset: offset of a tree node
898 * @compatible: string to match against
899 *
900 *
901 * fdt_node_check_compatible() returns 0 if the given node contains a
902 * 'compatible' property with the given string as one of its elements,
903 * it returns non-zero otherwise, or on error.
904 *
905 * returns:
906 *	0, if the node has a 'compatible' property listing the given string
907 *	1, if the node has a 'compatible' property, but it does not list
908 *		the given string
909 *	-FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
910 *	-FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
911 *	-FDT_ERR_BADMAGIC,
912 *	-FDT_ERR_BADVERSION,
913 *	-FDT_ERR_BADSTATE,
914 *	-FDT_ERR_BADSTRUCTURE, standard meanings
915 */
916int fdt_node_check_compatible(const void *fdt, int nodeoffset,
917			      const char *compatible);
918
919/**
920 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
921 * @fdt: pointer to the device tree blob
922 * @startoffset: only find nodes after this offset
923 * @compatible: 'compatible' string to match against
924 *
925 * fdt_node_offset_by_compatible() returns the offset of the first
926 * node after startoffset, which has a 'compatible' property which
927 * lists the given compatible string; or if startoffset is -1, the
928 * very first such node in the tree.
929 *
930 * To iterate through all nodes matching the criterion, the following
931 * idiom can be used:
932 *	offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
933 *	while (offset != -FDT_ERR_NOTFOUND) {
934 *		// other code here
935 *		offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
936 *	}
937 *
938 * Note the -1 in the first call to the function, if 0 is used here
939 * instead, the function will never locate the root node, even if it
940 * matches the criterion.
941 *
942 * returns:
943 *	structure block offset of the located node (>= 0, >startoffset),
944 *		 on success
945 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
946 *		tree after startoffset
947 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
948 *	-FDT_ERR_BADMAGIC,
949 *	-FDT_ERR_BADVERSION,
950 *	-FDT_ERR_BADSTATE,
951 *	-FDT_ERR_BADSTRUCTURE, standard meanings
952 */
953int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
954				  const char *compatible);
955
956/**
957 * fdt_stringlist_contains - check a string list property for a string
958 * @strlist: Property containing a list of strings to check
959 * @listlen: Length of property
960 * @str: String to search for
961 *
962 * This is a utility function provided for convenience. The list contains
963 * one or more strings, each terminated by \0, as is found in a device tree
964 * "compatible" property.
965 *
966 * @return: 1 if the string is found in the list, 0 not found, or invalid list
967 */
968int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
969
970/**
971 * fdt_stringlist_count - count the number of strings in a string list
972 * @fdt: pointer to the device tree blob
973 * @nodeoffset: offset of a tree node
974 * @property: name of the property containing the string list
975 * @return:
976 *   the number of strings in the given property
977 *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
978 *   -FDT_ERR_NOTFOUND if the property does not exist
979 */
980int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property);
981
982/**
983 * fdt_stringlist_search - find a string in a string list and return its index
984 * @fdt: pointer to the device tree blob
985 * @nodeoffset: offset of a tree node
986 * @property: name of the property containing the string list
987 * @string: string to look up in the string list
988 *
989 * Note that it is possible for this function to succeed on property values
990 * that are not NUL-terminated. That's because the function will stop after
991 * finding the first occurrence of @string. This can for example happen with
992 * small-valued cell properties, such as #address-cells, when searching for
993 * the empty string.
994 *
995 * @return:
996 *   the index of the string in the list of strings
997 *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
998 *   -FDT_ERR_NOTFOUND if the property does not exist or does not contain
999 *                     the given string
1000 */
1001int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
1002			  const char *string);
1003
1004/**
1005 * fdt_stringlist_get() - obtain the string at a given index in a string list
1006 * @fdt: pointer to the device tree blob
1007 * @nodeoffset: offset of a tree node
1008 * @property: name of the property containing the string list
1009 * @index: index of the string to return
1010 * @lenp: return location for the string length or an error code on failure
1011 *
1012 * Note that this will successfully extract strings from properties with
1013 * non-NUL-terminated values. For example on small-valued cell properties
1014 * this function will return the empty string.
1015 *
1016 * If non-NULL, the length of the string (on success) or a negative error-code
1017 * (on failure) will be stored in the integer pointer to by lenp.
1018 *
1019 * @return:
1020 *   A pointer to the string at the given index in the string list or NULL on
1021 *   failure. On success the length of the string will be stored in the memory
1022 *   location pointed to by the lenp parameter, if non-NULL. On failure one of
1023 *   the following negative error codes will be returned in the lenp parameter
1024 *   (if non-NULL):
1025 *     -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1026 *     -FDT_ERR_NOTFOUND if the property does not exist
1027 */
1028const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
1029			       const char *property, int index,
1030			       int *lenp);
1031
1032/**********************************************************************/
1033/* Read-only functions (addressing related)                           */
1034/**********************************************************************/
1035
1036/**
1037 * FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells
1038 *
1039 * This is the maximum value for #address-cells, #size-cells and
1040 * similar properties that will be processed by libfdt.  IEE1275
1041 * requires that OF implementations handle values up to 4.
1042 * Implementations may support larger values, but in practice higher
1043 * values aren't used.
1044 */
1045#define FDT_MAX_NCELLS		4
1046
1047/**
1048 * fdt_address_cells - retrieve address size for a bus represented in the tree
1049 * @fdt: pointer to the device tree blob
1050 * @nodeoffset: offset of the node to find the address size for
1051 *
1052 * When the node has a valid #address-cells property, returns its value.
1053 *
1054 * returns:
1055 *	0 <= n < FDT_MAX_NCELLS, on success
1056 *      2, if the node has no #address-cells property
1057 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1058 *		#address-cells property
1059 *	-FDT_ERR_BADMAGIC,
1060 *	-FDT_ERR_BADVERSION,
1061 *	-FDT_ERR_BADSTATE,
1062 *	-FDT_ERR_BADSTRUCTURE,
1063 *	-FDT_ERR_TRUNCATED, standard meanings
1064 */
1065int fdt_address_cells(const void *fdt, int nodeoffset);
1066
1067/**
1068 * fdt_size_cells - retrieve address range size for a bus represented in the
1069 *                  tree
1070 * @fdt: pointer to the device tree blob
1071 * @nodeoffset: offset of the node to find the address range size for
1072 *
1073 * When the node has a valid #size-cells property, returns its value.
1074 *
1075 * returns:
1076 *	0 <= n < FDT_MAX_NCELLS, on success
1077 *      2, if the node has no #address-cells property
1078 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1079 *		#size-cells property
1080 *	-FDT_ERR_BADMAGIC,
1081 *	-FDT_ERR_BADVERSION,
1082 *	-FDT_ERR_BADSTATE,
1083 *	-FDT_ERR_BADSTRUCTURE,
1084 *	-FDT_ERR_TRUNCATED, standard meanings
1085 */
1086int fdt_size_cells(const void *fdt, int nodeoffset);
1087
1088
1089/**********************************************************************/
1090/* Write-in-place functions                                           */
1091/**********************************************************************/
1092
1093/**
1094 * fdt_setprop_inplace_namelen_partial - change a property's value,
1095 *                                       but not its size
1096 * @fdt: pointer to the device tree blob
1097 * @nodeoffset: offset of the node whose property to change
1098 * @name: name of the property to change
1099 * @namelen: number of characters of name to consider
1100 * @idx: index of the property to change in the array
1101 * @val: pointer to data to replace the property value with
1102 * @len: length of the property value
1103 *
1104 * Identical to fdt_setprop_inplace(), but modifies the given property
1105 * starting from the given index, and using only the first characters
1106 * of the name. It is useful when you want to manipulate only one value of
1107 * an array and you have a string that doesn't end with \0.
1108 */
1109int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
1110					const char *name, int namelen,
1111					uint32_t idx, const void *val,
1112					int len);
1113
1114/**
1115 * fdt_setprop_inplace - change a property's value, but not its size
1116 * @fdt: pointer to the device tree blob
1117 * @nodeoffset: offset of the node whose property to change
1118 * @name: name of the property to change
1119 * @val: pointer to data to replace the property value with
1120 * @len: length of the property value
1121 *
1122 * fdt_setprop_inplace() replaces the value of a given property with
1123 * the data in val, of length len.  This function cannot change the
1124 * size of a property, and so will only work if len is equal to the
1125 * current length of the property.
1126 *
1127 * This function will alter only the bytes in the blob which contain
1128 * the given property value, and will not alter or move any other part
1129 * of the tree.
1130 *
1131 * returns:
1132 *	0, on success
1133 *	-FDT_ERR_NOSPACE, if len is not equal to the property's current length
1134 *	-FDT_ERR_NOTFOUND, node does not have the named property
1135 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1136 *	-FDT_ERR_BADMAGIC,
1137 *	-FDT_ERR_BADVERSION,
1138 *	-FDT_ERR_BADSTATE,
1139 *	-FDT_ERR_BADSTRUCTURE,
1140 *	-FDT_ERR_TRUNCATED, standard meanings
1141 */
1142int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
1143			const void *val, int len);
1144
1145/**
1146 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
1147 * @fdt: pointer to the device tree blob
1148 * @nodeoffset: offset of the node whose property to change
1149 * @name: name of the property to change
1150 * @val: 32-bit integer value to replace the property with
1151 *
1152 * fdt_setprop_inplace_u32() replaces the value of a given property
1153 * with the 32-bit integer value in val, converting val to big-endian
1154 * if necessary.  This function cannot change the size of a property,
1155 * and so will only work if the property already exists and has length
1156 * 4.
1157 *
1158 * This function will alter only the bytes in the blob which contain
1159 * the given property value, and will not alter or move any other part
1160 * of the tree.
1161 *
1162 * returns:
1163 *	0, on success
1164 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 4
1165 *	-FDT_ERR_NOTFOUND, node does not have the named property
1166 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1167 *	-FDT_ERR_BADMAGIC,
1168 *	-FDT_ERR_BADVERSION,
1169 *	-FDT_ERR_BADSTATE,
1170 *	-FDT_ERR_BADSTRUCTURE,
1171 *	-FDT_ERR_TRUNCATED, standard meanings
1172 */
1173static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
1174					  const char *name, uint32_t val)
1175{
1176	fdt32_t tmp = cpu_to_fdt32(val);
1177	return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1178}
1179
1180/**
1181 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
1182 * @fdt: pointer to the device tree blob
1183 * @nodeoffset: offset of the node whose property to change
1184 * @name: name of the property to change
1185 * @val: 64-bit integer value to replace the property with
1186 *
1187 * fdt_setprop_inplace_u64() replaces the value of a given property
1188 * with the 64-bit integer value in val, converting val to big-endian
1189 * if necessary.  This function cannot change the size of a property,
1190 * and so will only work if the property already exists and has length
1191 * 8.
1192 *
1193 * This function will alter only the bytes in the blob which contain
1194 * the given property value, and will not alter or move any other part
1195 * of the tree.
1196 *
1197 * returns:
1198 *	0, on success
1199 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 8
1200 *	-FDT_ERR_NOTFOUND, node does not have the named property
1201 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1202 *	-FDT_ERR_BADMAGIC,
1203 *	-FDT_ERR_BADVERSION,
1204 *	-FDT_ERR_BADSTATE,
1205 *	-FDT_ERR_BADSTRUCTURE,
1206 *	-FDT_ERR_TRUNCATED, standard meanings
1207 */
1208static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
1209					  const char *name, uint64_t val)
1210{
1211	fdt64_t tmp = cpu_to_fdt64(val);
1212	return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1213}
1214
1215/**
1216 * fdt_setprop_inplace_cell - change the value of a single-cell property
1217 *
1218 * This is an alternative name for fdt_setprop_inplace_u32()
1219 */
1220static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
1221					   const char *name, uint32_t val)
1222{
1223	return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
1224}
1225
1226/**
1227 * fdt_nop_property - replace a property with nop tags
1228 * @fdt: pointer to the device tree blob
1229 * @nodeoffset: offset of the node whose property to nop
1230 * @name: name of the property to nop
1231 *
1232 * fdt_nop_property() will replace a given property's representation
1233 * in the blob with FDT_NOP tags, effectively removing it from the
1234 * tree.
1235 *
1236 * This function will alter only the bytes in the blob which contain
1237 * the property, and will not alter or move any other part of the
1238 * tree.
1239 *
1240 * returns:
1241 *	0, on success
1242 *	-FDT_ERR_NOTFOUND, node does not have the named property
1243 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1244 *	-FDT_ERR_BADMAGIC,
1245 *	-FDT_ERR_BADVERSION,
1246 *	-FDT_ERR_BADSTATE,
1247 *	-FDT_ERR_BADSTRUCTURE,
1248 *	-FDT_ERR_TRUNCATED, standard meanings
1249 */
1250int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
1251
1252/**
1253 * fdt_nop_node - replace a node (subtree) with nop tags
1254 * @fdt: pointer to the device tree blob
1255 * @nodeoffset: offset of the node to nop
1256 *
1257 * fdt_nop_node() will replace a given node's representation in the
1258 * blob, including all its subnodes, if any, with FDT_NOP tags,
1259 * effectively removing it from the tree.
1260 *
1261 * This function will alter only the bytes in the blob which contain
1262 * the node and its properties and subnodes, and will not alter or
1263 * move any other part of the tree.
1264 *
1265 * returns:
1266 *	0, on success
1267 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1268 *	-FDT_ERR_BADMAGIC,
1269 *	-FDT_ERR_BADVERSION,
1270 *	-FDT_ERR_BADSTATE,
1271 *	-FDT_ERR_BADSTRUCTURE,
1272 *	-FDT_ERR_TRUNCATED, standard meanings
1273 */
1274int fdt_nop_node(void *fdt, int nodeoffset);
1275
1276/**********************************************************************/
1277/* Sequential write functions                                         */
1278/**********************************************************************/
1279
1280int fdt_create(void *buf, int bufsize);
1281int fdt_resize(void *fdt, void *buf, int bufsize);
1282int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
1283int fdt_finish_reservemap(void *fdt);
1284int fdt_begin_node(void *fdt, const char *name);
1285int fdt_property(void *fdt, const char *name, const void *val, int len);
1286static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
1287{
1288	fdt32_t tmp = cpu_to_fdt32(val);
1289	return fdt_property(fdt, name, &tmp, sizeof(tmp));
1290}
1291static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
1292{
1293	fdt64_t tmp = cpu_to_fdt64(val);
1294	return fdt_property(fdt, name, &tmp, sizeof(tmp));
1295}
1296static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
1297{
1298	return fdt_property_u32(fdt, name, val);
1299}
1300#define fdt_property_string(fdt, name, str) \
1301	fdt_property(fdt, name, str, strlen(str)+1)
1302int fdt_end_node(void *fdt);
1303int fdt_finish(void *fdt);
1304
1305/**********************************************************************/
1306/* Read-write functions                                               */
1307/**********************************************************************/
1308
1309int fdt_create_empty_tree(void *buf, int bufsize);
1310int fdt_open_into(const void *fdt, void *buf, int bufsize);
1311int fdt_pack(void *fdt);
1312
1313/**
1314 * fdt_add_mem_rsv - add one memory reserve map entry
1315 * @fdt: pointer to the device tree blob
1316 * @address, @size: 64-bit values (native endian)
1317 *
1318 * Adds a reserve map entry to the given blob reserving a region at
1319 * address address of length size.
1320 *
1321 * This function will insert data into the reserve map and will
1322 * therefore change the indexes of some entries in the table.
1323 *
1324 * returns:
1325 *	0, on success
1326 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1327 *		contain the new reservation entry
1328 *	-FDT_ERR_BADMAGIC,
1329 *	-FDT_ERR_BADVERSION,
1330 *	-FDT_ERR_BADSTATE,
1331 *	-FDT_ERR_BADSTRUCTURE,
1332 *	-FDT_ERR_BADLAYOUT,
1333 *	-FDT_ERR_TRUNCATED, standard meanings
1334 */
1335int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
1336
1337/**
1338 * fdt_del_mem_rsv - remove a memory reserve map entry
1339 * @fdt: pointer to the device tree blob
1340 * @n: entry to remove
1341 *
1342 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
1343 * the blob.
1344 *
1345 * This function will delete data from the reservation table and will
1346 * therefore change the indexes of some entries in the table.
1347 *
1348 * returns:
1349 *	0, on success
1350 *	-FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
1351 *		are less than n+1 reserve map entries)
1352 *	-FDT_ERR_BADMAGIC,
1353 *	-FDT_ERR_BADVERSION,
1354 *	-FDT_ERR_BADSTATE,
1355 *	-FDT_ERR_BADSTRUCTURE,
1356 *	-FDT_ERR_BADLAYOUT,
1357 *	-FDT_ERR_TRUNCATED, standard meanings
1358 */
1359int fdt_del_mem_rsv(void *fdt, int n);
1360
1361/**
1362 * fdt_set_name - change the name of a given node
1363 * @fdt: pointer to the device tree blob
1364 * @nodeoffset: structure block offset of a node
1365 * @name: name to give the node
1366 *
1367 * fdt_set_name() replaces the name (including unit address, if any)
1368 * of the given node with the given string.  NOTE: this function can't
1369 * efficiently check if the new name is unique amongst the given
1370 * node's siblings; results are undefined if this function is invoked
1371 * with a name equal to one of the given node's siblings.
1372 *
1373 * This function may insert or delete data from the blob, and will
1374 * therefore change the offsets of some existing nodes.
1375 *
1376 * returns:
1377 *	0, on success
1378 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob
1379 *		to contain the new name
1380 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1381 *	-FDT_ERR_BADMAGIC,
1382 *	-FDT_ERR_BADVERSION,
1383 *	-FDT_ERR_BADSTATE, standard meanings
1384 */
1385int fdt_set_name(void *fdt, int nodeoffset, const char *name);
1386
1387/**
1388 * fdt_setprop - create or change a property
1389 * @fdt: pointer to the device tree blob
1390 * @nodeoffset: offset of the node whose property to change
1391 * @name: name of the property to change
1392 * @val: pointer to data to set the property value to
1393 * @len: length of the property value
1394 *
1395 * fdt_setprop() sets the value of the named property in the given
1396 * node to the given value and length, creating the property if it
1397 * does not already exist.
1398 *
1399 * This function may insert or delete data from the blob, and will
1400 * therefore change the offsets of some existing nodes.
1401 *
1402 * returns:
1403 *	0, on success
1404 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1405 *		contain the new property value
1406 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1407 *	-FDT_ERR_BADLAYOUT,
1408 *	-FDT_ERR_BADMAGIC,
1409 *	-FDT_ERR_BADVERSION,
1410 *	-FDT_ERR_BADSTATE,
1411 *	-FDT_ERR_BADSTRUCTURE,
1412 *	-FDT_ERR_BADLAYOUT,
1413 *	-FDT_ERR_TRUNCATED, standard meanings
1414 */
1415int fdt_setprop(void *fdt, int nodeoffset, const char *name,
1416		const void *val, int len);
1417
1418/**
1419 * fdt_setprop_u32 - set a property to a 32-bit integer
1420 * @fdt: pointer to the device tree blob
1421 * @nodeoffset: offset of the node whose property to change
1422 * @name: name of the property to change
1423 * @val: 32-bit integer value for the property (native endian)
1424 *
1425 * fdt_setprop_u32() sets the value of the named property in the given
1426 * node to the given 32-bit integer value (converting to big-endian if
1427 * necessary), or creates a new property with that value if it does
1428 * not already exist.
1429 *
1430 * This function may insert or delete data from the blob, and will
1431 * therefore change the offsets of some existing nodes.
1432 *
1433 * returns:
1434 *	0, on success
1435 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1436 *		contain the new property value
1437 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1438 *	-FDT_ERR_BADLAYOUT,
1439 *	-FDT_ERR_BADMAGIC,
1440 *	-FDT_ERR_BADVERSION,
1441 *	-FDT_ERR_BADSTATE,
1442 *	-FDT_ERR_BADSTRUCTURE,
1443 *	-FDT_ERR_BADLAYOUT,
1444 *	-FDT_ERR_TRUNCATED, standard meanings
1445 */
1446static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
1447				  uint32_t val)
1448{
1449	fdt32_t tmp = cpu_to_fdt32(val);
1450	return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1451}
1452
1453/**
1454 * fdt_setprop_u64 - set a property to a 64-bit integer
1455 * @fdt: pointer to the device tree blob
1456 * @nodeoffset: offset of the node whose property to change
1457 * @name: name of the property to change
1458 * @val: 64-bit integer value for the property (native endian)
1459 *
1460 * fdt_setprop_u64() sets the value of the named property in the given
1461 * node to the given 64-bit integer value (converting to big-endian if
1462 * necessary), or creates a new property with that value if it does
1463 * not already exist.
1464 *
1465 * This function may insert or delete data from the blob, and will
1466 * therefore change the offsets of some existing nodes.
1467 *
1468 * returns:
1469 *	0, on success
1470 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1471 *		contain the new property value
1472 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1473 *	-FDT_ERR_BADLAYOUT,
1474 *	-FDT_ERR_BADMAGIC,
1475 *	-FDT_ERR_BADVERSION,
1476 *	-FDT_ERR_BADSTATE,
1477 *	-FDT_ERR_BADSTRUCTURE,
1478 *	-FDT_ERR_BADLAYOUT,
1479 *	-FDT_ERR_TRUNCATED, standard meanings
1480 */
1481static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
1482				  uint64_t val)
1483{
1484	fdt64_t tmp = cpu_to_fdt64(val);
1485	return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1486}
1487
1488/**
1489 * fdt_setprop_cell - set a property to a single cell value
1490 *
1491 * This is an alternative name for fdt_setprop_u32()
1492 */
1493static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
1494				   uint32_t val)
1495{
1496	return fdt_setprop_u32(fdt, nodeoffset, name, val);
1497}
1498
1499/**
1500 * fdt_setprop_string - set a property to a string value
1501 * @fdt: pointer to the device tree blob
1502 * @nodeoffset: offset of the node whose property to change
1503 * @name: name of the property to change
1504 * @str: string value for the property
1505 *
1506 * fdt_setprop_string() sets the value of the named property in the
1507 * given node to the given string value (using the length of the
1508 * string to determine the new length of the property), or creates a
1509 * new property with that value if it does not already exist.
1510 *
1511 * This function may insert or delete data from the blob, and will
1512 * therefore change the offsets of some existing nodes.
1513 *
1514 * returns:
1515 *	0, on success
1516 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1517 *		contain the new property value
1518 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1519 *	-FDT_ERR_BADLAYOUT,
1520 *	-FDT_ERR_BADMAGIC,
1521 *	-FDT_ERR_BADVERSION,
1522 *	-FDT_ERR_BADSTATE,
1523 *	-FDT_ERR_BADSTRUCTURE,
1524 *	-FDT_ERR_BADLAYOUT,
1525 *	-FDT_ERR_TRUNCATED, standard meanings
1526 */
1527#define fdt_setprop_string(fdt, nodeoffset, name, str) \
1528	fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1529
1530
1531/**
1532 * fdt_setprop_empty - set a property to an empty value
1533 * @fdt: pointer to the device tree blob
1534 * @nodeoffset: offset of the node whose property to change
1535 * @name: name of the property to change
1536 *
1537 * fdt_setprop_empty() sets the value of the named property in the
1538 * given node to an empty (zero length) value, or creates a new empty
1539 * property if it does not already exist.
1540 *
1541 * This function may insert or delete data from the blob, and will
1542 * therefore change the offsets of some existing nodes.
1543 *
1544 * returns:
1545 *	0, on success
1546 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1547 *		contain the new property value
1548 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1549 *	-FDT_ERR_BADLAYOUT,
1550 *	-FDT_ERR_BADMAGIC,
1551 *	-FDT_ERR_BADVERSION,
1552 *	-FDT_ERR_BADSTATE,
1553 *	-FDT_ERR_BADSTRUCTURE,
1554 *	-FDT_ERR_BADLAYOUT,
1555 *	-FDT_ERR_TRUNCATED, standard meanings
1556 */
1557#define fdt_setprop_empty(fdt, nodeoffset, name) \
1558	fdt_setprop((fdt), (nodeoffset), (name), NULL, 0)
1559
1560/**
1561 * fdt_appendprop - append to or create a property
1562 * @fdt: pointer to the device tree blob
1563 * @nodeoffset: offset of the node whose property to change
1564 * @name: name of the property to append to
1565 * @val: pointer to data to append to the property value
1566 * @len: length of the data to append to the property value
1567 *
1568 * fdt_appendprop() appends the value to the named property in the
1569 * given node, creating the property if it does not already exist.
1570 *
1571 * This function may insert data into the blob, and will therefore
1572 * change the offsets of some existing nodes.
1573 *
1574 * returns:
1575 *	0, on success
1576 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1577 *		contain the new property value
1578 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1579 *	-FDT_ERR_BADLAYOUT,
1580 *	-FDT_ERR_BADMAGIC,
1581 *	-FDT_ERR_BADVERSION,
1582 *	-FDT_ERR_BADSTATE,
1583 *	-FDT_ERR_BADSTRUCTURE,
1584 *	-FDT_ERR_BADLAYOUT,
1585 *	-FDT_ERR_TRUNCATED, standard meanings
1586 */
1587int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
1588		   const void *val, int len);
1589
1590/**
1591 * fdt_appendprop_u32 - append a 32-bit integer value to a property
1592 * @fdt: pointer to the device tree blob
1593 * @nodeoffset: offset of the node whose property to change
1594 * @name: name of the property to change
1595 * @val: 32-bit integer value to append to the property (native endian)
1596 *
1597 * fdt_appendprop_u32() appends the given 32-bit integer value
1598 * (converting to big-endian if necessary) to the value of the named
1599 * property in the given node, or creates a new property with that
1600 * value if it does not already exist.
1601 *
1602 * This function may insert data into the blob, and will therefore
1603 * change the offsets of some existing nodes.
1604 *
1605 * returns:
1606 *	0, on success
1607 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1608 *		contain the new property value
1609 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1610 *	-FDT_ERR_BADLAYOUT,
1611 *	-FDT_ERR_BADMAGIC,
1612 *	-FDT_ERR_BADVERSION,
1613 *	-FDT_ERR_BADSTATE,
1614 *	-FDT_ERR_BADSTRUCTURE,
1615 *	-FDT_ERR_BADLAYOUT,
1616 *	-FDT_ERR_TRUNCATED, standard meanings
1617 */
1618static inline int fdt_appendprop_u32(void *fdt, int nodeoffset,
1619				     const char *name, uint32_t val)
1620{
1621	fdt32_t tmp = cpu_to_fdt32(val);
1622	return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1623}
1624
1625/**
1626 * fdt_appendprop_u64 - append a 64-bit integer value to a property
1627 * @fdt: pointer to the device tree blob
1628 * @nodeoffset: offset of the node whose property to change
1629 * @name: name of the property to change
1630 * @val: 64-bit integer value to append to the property (native endian)
1631 *
1632 * fdt_appendprop_u64() appends the given 64-bit integer value
1633 * (converting to big-endian if necessary) to the value of the named
1634 * property in the given node, or creates a new property with that
1635 * value if it does not already exist.
1636 *
1637 * This function may insert data into the blob, and will therefore
1638 * change the offsets of some existing nodes.
1639 *
1640 * returns:
1641 *	0, on success
1642 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1643 *		contain the new property value
1644 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1645 *	-FDT_ERR_BADLAYOUT,
1646 *	-FDT_ERR_BADMAGIC,
1647 *	-FDT_ERR_BADVERSION,
1648 *	-FDT_ERR_BADSTATE,
1649 *	-FDT_ERR_BADSTRUCTURE,
1650 *	-FDT_ERR_BADLAYOUT,
1651 *	-FDT_ERR_TRUNCATED, standard meanings
1652 */
1653static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
1654				     const char *name, uint64_t val)
1655{
1656	fdt64_t tmp = cpu_to_fdt64(val);
1657	return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1658}
1659
1660/**
1661 * fdt_appendprop_cell - append a single cell value to a property
1662 *
1663 * This is an alternative name for fdt_appendprop_u32()
1664 */
1665static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
1666				      const char *name, uint32_t val)
1667{
1668	return fdt_appendprop_u32(fdt, nodeoffset, name, val);
1669}
1670
1671/**
1672 * fdt_appendprop_string - append a string to a property
1673 * @fdt: pointer to the device tree blob
1674 * @nodeoffset: offset of the node whose property to change
1675 * @name: name of the property to change
1676 * @str: string value to append to the property
1677 *
1678 * fdt_appendprop_string() appends the given string to the value of
1679 * the named property in the given node, or creates a new property
1680 * with that value if it does not already exist.
1681 *
1682 * This function may insert data into the blob, and will therefore
1683 * change the offsets of some existing nodes.
1684 *
1685 * returns:
1686 *	0, on success
1687 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1688 *		contain the new property value
1689 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1690 *	-FDT_ERR_BADLAYOUT,
1691 *	-FDT_ERR_BADMAGIC,
1692 *	-FDT_ERR_BADVERSION,
1693 *	-FDT_ERR_BADSTATE,
1694 *	-FDT_ERR_BADSTRUCTURE,
1695 *	-FDT_ERR_BADLAYOUT,
1696 *	-FDT_ERR_TRUNCATED, standard meanings
1697 */
1698#define fdt_appendprop_string(fdt, nodeoffset, name, str) \
1699	fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1700
1701/**
1702 * fdt_delprop - delete a property
1703 * @fdt: pointer to the device tree blob
1704 * @nodeoffset: offset of the node whose property to nop
1705 * @name: name of the property to nop
1706 *
1707 * fdt_del_property() will delete the given property.
1708 *
1709 * This function will delete data from the blob, and will therefore
1710 * change the offsets of some existing nodes.
1711 *
1712 * returns:
1713 *	0, on success
1714 *	-FDT_ERR_NOTFOUND, node does not have the named property
1715 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1716 *	-FDT_ERR_BADLAYOUT,
1717 *	-FDT_ERR_BADMAGIC,
1718 *	-FDT_ERR_BADVERSION,
1719 *	-FDT_ERR_BADSTATE,
1720 *	-FDT_ERR_BADSTRUCTURE,
1721 *	-FDT_ERR_TRUNCATED, standard meanings
1722 */
1723int fdt_delprop(void *fdt, int nodeoffset, const char *name);
1724
1725/**
1726 * fdt_add_subnode_namelen - creates a new node based on substring
1727 * @fdt: pointer to the device tree blob
1728 * @parentoffset: structure block offset of a node
1729 * @name: name of the subnode to locate
1730 * @namelen: number of characters of name to consider
1731 *
1732 * Identical to fdt_add_subnode(), but use only the first namelen
1733 * characters of name as the name of the new node.  This is useful for
1734 * creating subnodes based on a portion of a larger string, such as a
1735 * full path.
1736 */
1737int fdt_add_subnode_namelen(void *fdt, int parentoffset,
1738			    const char *name, int namelen);
1739
1740/**
1741 * fdt_add_subnode - creates a new node
1742 * @fdt: pointer to the device tree blob
1743 * @parentoffset: structure block offset of a node
1744 * @name: name of the subnode to locate
1745 *
1746 * fdt_add_subnode() creates a new node as a subnode of the node at
1747 * structure block offset parentoffset, with the given name (which
1748 * should include the unit address, if any).
1749 *
1750 * This function will insert data into the blob, and will therefore
1751 * change the offsets of some existing nodes.
1752
1753 * returns:
1754 *	structure block offset of the created nodeequested subnode (>=0), on
1755 *		success
1756 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
1757 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
1758 *		tag
1759 *	-FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
1760 *		the given name
1761 *	-FDT_ERR_NOSPACE, if there is insufficient free space in the
1762 *		blob to contain the new node
1763 *	-FDT_ERR_NOSPACE
1764 *	-FDT_ERR_BADLAYOUT
1765 *      -FDT_ERR_BADMAGIC,
1766 *	-FDT_ERR_BADVERSION,
1767 *	-FDT_ERR_BADSTATE,
1768 *	-FDT_ERR_BADSTRUCTURE,
1769 *	-FDT_ERR_TRUNCATED, standard meanings.
1770 */
1771int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
1772
1773/**
1774 * fdt_del_node - delete a node (subtree)
1775 * @fdt: pointer to the device tree blob
1776 * @nodeoffset: offset of the node to nop
1777 *
1778 * fdt_del_node() will remove the given node, including all its
1779 * subnodes if any, from the blob.
1780 *
1781 * This function will delete data from the blob, and will therefore
1782 * change the offsets of some existing nodes.
1783 *
1784 * returns:
1785 *	0, on success
1786 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1787 *	-FDT_ERR_BADLAYOUT,
1788 *	-FDT_ERR_BADMAGIC,
1789 *	-FDT_ERR_BADVERSION,
1790 *	-FDT_ERR_BADSTATE,
1791 *	-FDT_ERR_BADSTRUCTURE,
1792 *	-FDT_ERR_TRUNCATED, standard meanings
1793 */
1794int fdt_del_node(void *fdt, int nodeoffset);
1795
1796/**
1797 * fdt_overlay_apply - Applies a DT overlay on a base DT
1798 * @fdt: pointer to the base device tree blob
1799 * @fdto: pointer to the device tree overlay blob
1800 *
1801 * fdt_overlay_apply() will apply the given device tree overlay on the
1802 * given base device tree.
1803 *
1804 * Expect the base device tree to be modified, even if the function
1805 * returns an error.
1806 *
1807 * returns:
1808 *	0, on success
1809 *	-FDT_ERR_NOSPACE, there's not enough space in the base device tree
1810 *	-FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
1811 *		properties in the base DT
1812 *	-FDT_ERR_BADPHANDLE,
1813 *	-FDT_ERR_BADOVERLAY,
1814 *	-FDT_ERR_NOPHANDLES,
1815 *	-FDT_ERR_INTERNAL,
1816 *	-FDT_ERR_BADLAYOUT,
1817 *	-FDT_ERR_BADMAGIC,
1818 *	-FDT_ERR_BADOFFSET,
1819 *	-FDT_ERR_BADPATH,
1820 *	-FDT_ERR_BADVERSION,
1821 *	-FDT_ERR_BADSTRUCTURE,
1822 *	-FDT_ERR_BADSTATE,
1823 *	-FDT_ERR_TRUNCATED, standard meanings
1824 */
1825int fdt_overlay_apply(void *fdt, void *fdto);
1826
1827/**********************************************************************/
1828/* Debugging / informational functions                                */
1829/**********************************************************************/
1830
1831const char *fdt_strerror(int errval);
1832
1833#endif /* _LIBFDT_H */
1834