1#ifndef LIBFDT_H
2#define LIBFDT_H
3/*
4 * libfdt - Flat Device Tree manipulation
5 * Copyright (C) 2006 David Gibson, IBM Corporation.
6 *
7 * libfdt is dual licensed: you can use it either under the terms of
8 * the GPL, or the BSD license, at your option.
9 *
10 *  a) This library is free software; you can redistribute it and/or
11 *     modify it under the terms of the GNU General Public License as
12 *     published by the Free Software Foundation; either version 2 of the
13 *     License, or (at your option) any later version.
14 *
15 *     This library is distributed in the hope that it will be useful,
16 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
17 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18 *     GNU General Public License for more details.
19 *
20 *     You should have received a copy of the GNU General Public
21 *     License along with this library; if not, write to the Free
22 *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
23 *     MA 02110-1301 USA
24 *
25 * Alternatively,
26 *
27 *  b) Redistribution and use in source and binary forms, with or
28 *     without modification, are permitted provided that the following
29 *     conditions are met:
30 *
31 *     1. Redistributions of source code must retain the above
32 *        copyright notice, this list of conditions and the following
33 *        disclaimer.
34 *     2. Redistributions in binary form must reproduce the above
35 *        copyright notice, this list of conditions and the following
36 *        disclaimer in the documentation and/or other materials
37 *        provided with the distribution.
38 *
39 *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
40 *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
41 *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
42 *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
43 *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
44 *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45 *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46 *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47 *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
49 *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
50 *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
51 *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
52 */
53
54#include <libfdt_env.h>
55#include <fdt.h>
56
57#define FDT_FIRST_SUPPORTED_VERSION	0x02
58#define FDT_LAST_SUPPORTED_VERSION	0x11
59
60/* Error codes: informative error codes */
61#define FDT_ERR_NOTFOUND	1
62	/* FDT_ERR_NOTFOUND: The requested node or property does not exist */
63#define FDT_ERR_EXISTS		2
64	/* FDT_ERR_EXISTS: Attempted to create a node or property which
65	 * already exists */
66#define FDT_ERR_NOSPACE		3
67	/* FDT_ERR_NOSPACE: Operation needed to expand the device
68	 * tree, but its buffer did not have sufficient space to
69	 * contain the expanded tree. Use fdt_open_into() to move the
70	 * device tree to a buffer with more space. */
71
72/* Error codes: codes for bad parameters */
73#define FDT_ERR_BADOFFSET	4
74	/* FDT_ERR_BADOFFSET: Function was passed a structure block
75	 * offset which is out-of-bounds, or which points to an
76	 * unsuitable part of the structure for the operation. */
77#define FDT_ERR_BADPATH		5
78	/* FDT_ERR_BADPATH: Function was passed a badly formatted path
79	 * (e.g. missing a leading / for a function which requires an
80	 * absolute path) */
81#define FDT_ERR_BADPHANDLE	6
82	/* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle.
83	 * This can be caused either by an invalid phandle property
84	 * length, or the phandle value was either 0 or -1, which are
85	 * not permitted. */
86#define FDT_ERR_BADSTATE	7
87	/* FDT_ERR_BADSTATE: Function was passed an incomplete device
88	 * tree created by the sequential-write functions, which is
89	 * not sufficiently complete for the requested operation. */
90
91/* Error codes: codes for bad device tree blobs */
92#define FDT_ERR_TRUNCATED	8
93	/* FDT_ERR_TRUNCATED: Structure block of the given device tree
94	 * ends without an FDT_END tag. */
95#define FDT_ERR_BADMAGIC	9
96	/* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
97	 * device tree at all - it is missing the flattened device
98	 * tree magic number. */
99#define FDT_ERR_BADVERSION	10
100	/* FDT_ERR_BADVERSION: Given device tree has a version which
101	 * can't be handled by the requested operation.  For
102	 * read-write functions, this may mean that fdt_open_into() is
103	 * required to convert the tree to the expected version. */
104#define FDT_ERR_BADSTRUCTURE	11
105	/* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt
106	 * structure block or other serious error (e.g. misnested
107	 * nodes, or subnodes preceding properties). */
108#define FDT_ERR_BADLAYOUT	12
109	/* FDT_ERR_BADLAYOUT: For read-write functions, the given
110	 * device tree has it's sub-blocks in an order that the
111	 * function can't handle (memory reserve map, then structure,
112	 * then strings).  Use fdt_open_into() to reorganize the tree
113	 * into a form suitable for the read-write operations. */
114
115/* "Can't happen" error indicating a bug in libfdt */
116#define FDT_ERR_INTERNAL	13
117	/* FDT_ERR_INTERNAL: libfdt has failed an internal assertion.
118	 * Should never be returned, if it is, it indicates a bug in
119	 * libfdt itself. */
120
121/* Errors in device tree content */
122#define FDT_ERR_BADNCELLS	14
123	/* FDT_ERR_BADNCELLS: Device tree has a #address-cells, #size-cells
124	 * or similar property with a bad format or value */
125
126#define FDT_ERR_BADVALUE	15
127	/* FDT_ERR_BADVALUE: Device tree has a property with an unexpected
128	 * value. For example: a property expected to contain a string list
129	 * is not NUL-terminated within the length of its value. */
130
131#define FDT_ERR_BADOVERLAY	16
132	/* FDT_ERR_BADOVERLAY: The device tree overlay, while
133	 * correctly structured, cannot be applied due to some
134	 * unexpected or missing value, property or node. */
135
136#define FDT_ERR_NOPHANDLES	17
137	/* FDT_ERR_NOPHANDLES: The device tree doesn't have any
138	 * phandle available anymore without causing an overflow */
139
140#define FDT_ERR_MAX		17
141
142/**********************************************************************/
143/* Low-level functions (you probably don't need these)                */
144/**********************************************************************/
145
146#ifndef SWIG /* This function is not useful in Python */
147const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen);
148#endif
149static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
150{
151	return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
152}
153
154uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
155
156/**********************************************************************/
157/* Traversal functions                                                */
158/**********************************************************************/
159
160int fdt_next_node(const void *fdt, int offset, int *depth);
161
162/**
163 * fdt_first_subnode() - get offset of first direct subnode
164 *
165 * @fdt:	FDT blob
166 * @offset:	Offset of node to check
167 * @return offset of first subnode, or -FDT_ERR_NOTFOUND if there is none
168 */
169int fdt_first_subnode(const void *fdt, int offset);
170
171/**
172 * fdt_next_subnode() - get offset of next direct subnode
173 *
174 * After first calling fdt_first_subnode(), call this function repeatedly to
175 * get direct subnodes of a parent node.
176 *
177 * @fdt:	FDT blob
178 * @offset:	Offset of previous subnode
179 * @return offset of next subnode, or -FDT_ERR_NOTFOUND if there are no more
180 * subnodes
181 */
182int fdt_next_subnode(const void *fdt, int offset);
183
184/**
185 * fdt_for_each_subnode - iterate over all subnodes of a parent
186 *
187 * @node:	child node (int, lvalue)
188 * @fdt:	FDT blob (const void *)
189 * @parent:	parent node (int)
190 *
191 * This is actually a wrapper around a for loop and would be used like so:
192 *
193 *	fdt_for_each_subnode(node, fdt, parent) {
194 *		Use node
195 *		...
196 *	}
197 *
198 *	if ((node < 0) && (node != -FDT_ERR_NOT_FOUND)) {
199 *		Error handling
200 *	}
201 *
202 * Note that this is implemented as a macro and @node is used as
203 * iterator in the loop. The parent variable be constant or even a
204 * literal.
205 *
206 */
207#define fdt_for_each_subnode(node, fdt, parent)		\
208	for (node = fdt_first_subnode(fdt, parent);	\
209	     node >= 0;					\
210	     node = fdt_next_subnode(fdt, node))
211
212/**********************************************************************/
213/* General functions                                                  */
214/**********************************************************************/
215#define fdt_get_header(fdt, field) \
216	(fdt32_to_cpu(((const struct fdt_header *)(fdt))->field))
217#define fdt_magic(fdt)			(fdt_get_header(fdt, magic))
218#define fdt_totalsize(fdt)		(fdt_get_header(fdt, totalsize))
219#define fdt_off_dt_struct(fdt)		(fdt_get_header(fdt, off_dt_struct))
220#define fdt_off_dt_strings(fdt)		(fdt_get_header(fdt, off_dt_strings))
221#define fdt_off_mem_rsvmap(fdt)		(fdt_get_header(fdt, off_mem_rsvmap))
222#define fdt_version(fdt)		(fdt_get_header(fdt, version))
223#define fdt_last_comp_version(fdt)	(fdt_get_header(fdt, last_comp_version))
224#define fdt_boot_cpuid_phys(fdt)	(fdt_get_header(fdt, boot_cpuid_phys))
225#define fdt_size_dt_strings(fdt)	(fdt_get_header(fdt, size_dt_strings))
226#define fdt_size_dt_struct(fdt)		(fdt_get_header(fdt, size_dt_struct))
227
228#define fdt_set_hdr_(name) \
229	static inline void fdt_set_##name(void *fdt, uint32_t val) \
230	{ \
231		struct fdt_header *fdth = (struct fdt_header *)fdt; \
232		fdth->name = cpu_to_fdt32(val); \
233	}
234fdt_set_hdr_(magic);
235fdt_set_hdr_(totalsize);
236fdt_set_hdr_(off_dt_struct);
237fdt_set_hdr_(off_dt_strings);
238fdt_set_hdr_(off_mem_rsvmap);
239fdt_set_hdr_(version);
240fdt_set_hdr_(last_comp_version);
241fdt_set_hdr_(boot_cpuid_phys);
242fdt_set_hdr_(size_dt_strings);
243fdt_set_hdr_(size_dt_struct);
244#undef fdt_set_hdr_
245
246/**
247 * fdt_check_header - sanity check a device tree or possible device tree
248 * @fdt: pointer to data which might be a flattened device tree
249 *
250 * fdt_check_header() checks that the given buffer contains what
251 * appears to be a flattened device tree with sane information in its
252 * header.
253 *
254 * returns:
255 *     0, if the buffer appears to contain a valid device tree
256 *     -FDT_ERR_BADMAGIC,
257 *     -FDT_ERR_BADVERSION,
258 *     -FDT_ERR_BADSTATE, standard meanings, as above
259 */
260int fdt_check_header(const void *fdt);
261
262/**
263 * fdt_move - move a device tree around in memory
264 * @fdt: pointer to the device tree to move
265 * @buf: pointer to memory where the device is to be moved
266 * @bufsize: size of the memory space at buf
267 *
268 * fdt_move() relocates, if possible, the device tree blob located at
269 * fdt to the buffer at buf of size bufsize.  The buffer may overlap
270 * with the existing device tree blob at fdt.  Therefore,
271 *     fdt_move(fdt, fdt, fdt_totalsize(fdt))
272 * should always succeed.
273 *
274 * returns:
275 *     0, on success
276 *     -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
277 *     -FDT_ERR_BADMAGIC,
278 *     -FDT_ERR_BADVERSION,
279 *     -FDT_ERR_BADSTATE, standard meanings
280 */
281int fdt_move(const void *fdt, void *buf, int bufsize);
282
283/**********************************************************************/
284/* Read-only functions                                                */
285/**********************************************************************/
286
287/**
288 * fdt_string - retrieve a string from the strings block of a device tree
289 * @fdt: pointer to the device tree blob
290 * @stroffset: offset of the string within the strings block (native endian)
291 *
292 * fdt_string() retrieves a pointer to a single string from the
293 * strings block of the device tree blob at fdt.
294 *
295 * returns:
296 *     a pointer to the string, on success
297 *     NULL, if stroffset is out of bounds
298 */
299const char *fdt_string(const void *fdt, int stroffset);
300
301/**
302 * fdt_get_max_phandle - retrieves the highest phandle in a tree
303 * @fdt: pointer to the device tree blob
304 *
305 * fdt_get_max_phandle retrieves the highest phandle in the given
306 * device tree. This will ignore badly formatted phandles, or phandles
307 * with a value of 0 or -1.
308 *
309 * returns:
310 *      the highest phandle on success
311 *      0, if no phandle was found in the device tree
312 *      -1, if an error occurred
313 */
314uint32_t fdt_get_max_phandle(const void *fdt);
315
316/**
317 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
318 * @fdt: pointer to the device tree blob
319 *
320 * Returns the number of entries in the device tree blob's memory
321 * reservation map.  This does not include the terminating 0,0 entry
322 * or any other (0,0) entries reserved for expansion.
323 *
324 * returns:
325 *     the number of entries
326 */
327int fdt_num_mem_rsv(const void *fdt);
328
329/**
330 * fdt_get_mem_rsv - retrieve one memory reserve map entry
331 * @fdt: pointer to the device tree blob
332 * @address, @size: pointers to 64-bit variables
333 *
334 * On success, *address and *size will contain the address and size of
335 * the n-th reserve map entry from the device tree blob, in
336 * native-endian format.
337 *
338 * returns:
339 *     0, on success
340 *     -FDT_ERR_BADMAGIC,
341 *     -FDT_ERR_BADVERSION,
342 *     -FDT_ERR_BADSTATE, standard meanings
343 */
344int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
345
346/**
347 * fdt_subnode_offset_namelen - find a subnode based on substring
348 * @fdt: pointer to the device tree blob
349 * @parentoffset: structure block offset of a node
350 * @name: name of the subnode to locate
351 * @namelen: number of characters of name to consider
352 *
353 * Identical to fdt_subnode_offset(), but only examine the first
354 * namelen characters of name for matching the subnode name.  This is
355 * useful for finding subnodes based on a portion of a larger string,
356 * such as a full path.
357 */
358#ifndef SWIG /* Not available in Python */
359int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
360			       const char *name, int namelen);
361#endif
362/**
363 * fdt_subnode_offset - find a subnode of a given node
364 * @fdt: pointer to the device tree blob
365 * @parentoffset: structure block offset of a node
366 * @name: name of the subnode to locate
367 *
368 * fdt_subnode_offset() finds a subnode of the node at structure block
369 * offset parentoffset with the given name.  name may include a unit
370 * address, in which case fdt_subnode_offset() will find the subnode
371 * with that unit address, or the unit address may be omitted, in
372 * which case fdt_subnode_offset() will find an arbitrary subnode
373 * whose name excluding unit address matches the given name.
374 *
375 * returns:
376 *	structure block offset of the requested subnode (>=0), on success
377 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
378 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
379 *		tag
380 *	-FDT_ERR_BADMAGIC,
381 *	-FDT_ERR_BADVERSION,
382 *	-FDT_ERR_BADSTATE,
383 *	-FDT_ERR_BADSTRUCTURE,
384 *	-FDT_ERR_TRUNCATED, standard meanings.
385 */
386int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
387
388/**
389 * fdt_path_offset_namelen - find a tree node by its full path
390 * @fdt: pointer to the device tree blob
391 * @path: full path of the node to locate
392 * @namelen: number of characters of path to consider
393 *
394 * Identical to fdt_path_offset(), but only consider the first namelen
395 * characters of path as the path name.
396 */
397#ifndef SWIG /* Not available in Python */
398int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen);
399#endif
400
401/**
402 * fdt_path_offset - find a tree node by its full path
403 * @fdt: pointer to the device tree blob
404 * @path: full path of the node to locate
405 *
406 * fdt_path_offset() finds a node of a given path in the device tree.
407 * Each path component may omit the unit address portion, but the
408 * results of this are undefined if any such path component is
409 * ambiguous (that is if there are multiple nodes at the relevant
410 * level matching the given component, differentiated only by unit
411 * address).
412 *
413 * returns:
414 *	structure block offset of the node with the requested path (>=0), on
415 *		success
416 *	-FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
417 *	-FDT_ERR_NOTFOUND, if the requested node does not exist
418 *      -FDT_ERR_BADMAGIC,
419 *	-FDT_ERR_BADVERSION,
420 *	-FDT_ERR_BADSTATE,
421 *	-FDT_ERR_BADSTRUCTURE,
422 *	-FDT_ERR_TRUNCATED, standard meanings.
423 */
424int fdt_path_offset(const void *fdt, const char *path);
425
426/**
427 * fdt_get_name - retrieve the name of a given node
428 * @fdt: pointer to the device tree blob
429 * @nodeoffset: structure block offset of the starting node
430 * @lenp: pointer to an integer variable (will be overwritten) or NULL
431 *
432 * fdt_get_name() retrieves the name (including unit address) of the
433 * device tree node at structure block offset nodeoffset.  If lenp is
434 * non-NULL, the length of this name is also returned, in the integer
435 * pointed to by lenp.
436 *
437 * returns:
438 *	pointer to the node's name, on success
439 *		If lenp is non-NULL, *lenp contains the length of that name
440 *			(>=0)
441 *	NULL, on error
442 *		if lenp is non-NULL *lenp contains an error code (<0):
443 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
444 *			tag
445 *		-FDT_ERR_BADMAGIC,
446 *		-FDT_ERR_BADVERSION,
447 *		-FDT_ERR_BADSTATE, standard meanings
448 */
449const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
450
451/**
452 * fdt_first_property_offset - find the offset of a node's first property
453 * @fdt: pointer to the device tree blob
454 * @nodeoffset: structure block offset of a node
455 *
456 * fdt_first_property_offset() finds the first property of the node at
457 * the given structure block offset.
458 *
459 * returns:
460 *	structure block offset of the property (>=0), on success
461 *	-FDT_ERR_NOTFOUND, if the requested node has no properties
462 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
463 *      -FDT_ERR_BADMAGIC,
464 *	-FDT_ERR_BADVERSION,
465 *	-FDT_ERR_BADSTATE,
466 *	-FDT_ERR_BADSTRUCTURE,
467 *	-FDT_ERR_TRUNCATED, standard meanings.
468 */
469int fdt_first_property_offset(const void *fdt, int nodeoffset);
470
471/**
472 * fdt_next_property_offset - step through a node's properties
473 * @fdt: pointer to the device tree blob
474 * @offset: structure block offset of a property
475 *
476 * fdt_next_property_offset() finds the property immediately after the
477 * one at the given structure block offset.  This will be a property
478 * of the same node as the given property.
479 *
480 * returns:
481 *	structure block offset of the next property (>=0), on success
482 *	-FDT_ERR_NOTFOUND, if the given property is the last in its node
483 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag
484 *      -FDT_ERR_BADMAGIC,
485 *	-FDT_ERR_BADVERSION,
486 *	-FDT_ERR_BADSTATE,
487 *	-FDT_ERR_BADSTRUCTURE,
488 *	-FDT_ERR_TRUNCATED, standard meanings.
489 */
490int fdt_next_property_offset(const void *fdt, int offset);
491
492/**
493 * fdt_for_each_property_offset - iterate over all properties of a node
494 *
495 * @property_offset:	property offset (int, lvalue)
496 * @fdt:		FDT blob (const void *)
497 * @node:		node offset (int)
498 *
499 * This is actually a wrapper around a for loop and would be used like so:
500 *
501 *	fdt_for_each_property_offset(property, fdt, node) {
502 *		Use property
503 *		...
504 *	}
505 *
506 *	if ((property < 0) && (property != -FDT_ERR_NOT_FOUND)) {
507 *		Error handling
508 *	}
509 *
510 * Note that this is implemented as a macro and property is used as
511 * iterator in the loop. The node variable can be constant or even a
512 * literal.
513 */
514#define fdt_for_each_property_offset(property, fdt, node)	\
515	for (property = fdt_first_property_offset(fdt, node);	\
516	     property >= 0;					\
517	     property = fdt_next_property_offset(fdt, property))
518
519/**
520 * fdt_get_property_by_offset - retrieve the property at a given offset
521 * @fdt: pointer to the device tree blob
522 * @offset: offset of the property to retrieve
523 * @lenp: pointer to an integer variable (will be overwritten) or NULL
524 *
525 * fdt_get_property_by_offset() retrieves a pointer to the
526 * fdt_property structure within the device tree blob at the given
527 * offset.  If lenp is non-NULL, the length of the property value is
528 * also returned, in the integer pointed to by lenp.
529 *
530 * Note that this code only works on device tree versions >= 16. fdt_getprop()
531 * works on all versions.
532 *
533 * returns:
534 *	pointer to the structure representing the property
535 *		if lenp is non-NULL, *lenp contains the length of the property
536 *		value (>=0)
537 *	NULL, on error
538 *		if lenp is non-NULL, *lenp contains an error code (<0):
539 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
540 *		-FDT_ERR_BADMAGIC,
541 *		-FDT_ERR_BADVERSION,
542 *		-FDT_ERR_BADSTATE,
543 *		-FDT_ERR_BADSTRUCTURE,
544 *		-FDT_ERR_TRUNCATED, standard meanings
545 */
546const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
547						      int offset,
548						      int *lenp);
549
550/**
551 * fdt_get_property_namelen - find a property based on substring
552 * @fdt: pointer to the device tree blob
553 * @nodeoffset: offset of the node whose property to find
554 * @name: name of the property to find
555 * @namelen: number of characters of name to consider
556 * @lenp: pointer to an integer variable (will be overwritten) or NULL
557 *
558 * Identical to fdt_get_property(), but only examine the first namelen
559 * characters of name for matching the property name.
560 */
561#ifndef SWIG /* Not available in Python */
562const struct fdt_property *fdt_get_property_namelen(const void *fdt,
563						    int nodeoffset,
564						    const char *name,
565						    int namelen, int *lenp);
566#endif
567
568/**
569 * fdt_get_property - find a given property in a given node
570 * @fdt: pointer to the device tree blob
571 * @nodeoffset: offset of the node whose property to find
572 * @name: name of the property to find
573 * @lenp: pointer to an integer variable (will be overwritten) or NULL
574 *
575 * fdt_get_property() retrieves a pointer to the fdt_property
576 * structure within the device tree blob corresponding to the property
577 * named 'name' of the node at offset nodeoffset.  If lenp is
578 * non-NULL, the length of the property value is also returned, in the
579 * integer pointed to by lenp.
580 *
581 * returns:
582 *	pointer to the structure representing the property
583 *		if lenp is non-NULL, *lenp contains the length of the property
584 *		value (>=0)
585 *	NULL, on error
586 *		if lenp is non-NULL, *lenp contains an error code (<0):
587 *		-FDT_ERR_NOTFOUND, node does not have named property
588 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
589 *			tag
590 *		-FDT_ERR_BADMAGIC,
591 *		-FDT_ERR_BADVERSION,
592 *		-FDT_ERR_BADSTATE,
593 *		-FDT_ERR_BADSTRUCTURE,
594 *		-FDT_ERR_TRUNCATED, standard meanings
595 */
596const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
597					    const char *name, int *lenp);
598static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
599						      const char *name,
600						      int *lenp)
601{
602	return (struct fdt_property *)(uintptr_t)
603		fdt_get_property(fdt, nodeoffset, name, lenp);
604}
605
606/**
607 * fdt_getprop_by_offset - retrieve the value of a property at a given offset
608 * @fdt: pointer to the device tree blob
609 * @ffset: offset of the property to read
610 * @namep: pointer to a string variable (will be overwritten) or NULL
611 * @lenp: pointer to an integer variable (will be overwritten) or NULL
612 *
613 * fdt_getprop_by_offset() retrieves a pointer to the value of the
614 * property at structure block offset 'offset' (this will be a pointer
615 * to within the device blob itself, not a copy of the value).  If
616 * lenp is non-NULL, the length of the property value is also
617 * returned, in the integer pointed to by lenp.  If namep is non-NULL,
618 * the property's namne will also be returned in the char * pointed to
619 * by namep (this will be a pointer to within the device tree's string
620 * block, not a new copy of the name).
621 *
622 * returns:
623 *	pointer to the property's value
624 *		if lenp is non-NULL, *lenp contains the length of the property
625 *		value (>=0)
626 *		if namep is non-NULL *namep contiains a pointer to the property
627 *		name.
628 *	NULL, on error
629 *		if lenp is non-NULL, *lenp contains an error code (<0):
630 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
631 *		-FDT_ERR_BADMAGIC,
632 *		-FDT_ERR_BADVERSION,
633 *		-FDT_ERR_BADSTATE,
634 *		-FDT_ERR_BADSTRUCTURE,
635 *		-FDT_ERR_TRUNCATED, standard meanings
636 */
637#ifndef SWIG /* This function is not useful in Python */
638const void *fdt_getprop_by_offset(const void *fdt, int offset,
639				  const char **namep, int *lenp);
640#endif
641
642/**
643 * fdt_getprop_namelen - get property value based on substring
644 * @fdt: pointer to the device tree blob
645 * @nodeoffset: offset of the node whose property to find
646 * @name: name of the property to find
647 * @namelen: number of characters of name to consider
648 * @lenp: pointer to an integer variable (will be overwritten) or NULL
649 *
650 * Identical to fdt_getprop(), but only examine the first namelen
651 * characters of name for matching the property name.
652 */
653#ifndef SWIG /* Not available in Python */
654const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
655				const char *name, int namelen, int *lenp);
656static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset,
657					  const char *name, int namelen,
658					  int *lenp)
659{
660	return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name,
661						      namelen, lenp);
662}
663#endif
664
665/**
666 * fdt_getprop - retrieve the value of a given property
667 * @fdt: pointer to the device tree blob
668 * @nodeoffset: offset of the node whose property to find
669 * @name: name of the property to find
670 * @lenp: pointer to an integer variable (will be overwritten) or NULL
671 *
672 * fdt_getprop() retrieves a pointer to the value of the property
673 * named 'name' of the node at offset nodeoffset (this will be a
674 * pointer to within the device blob itself, not a copy of the value).
675 * If lenp is non-NULL, the length of the property value is also
676 * returned, in the integer pointed to by lenp.
677 *
678 * returns:
679 *	pointer to the property's value
680 *		if lenp is non-NULL, *lenp contains the length of the property
681 *		value (>=0)
682 *	NULL, on error
683 *		if lenp is non-NULL, *lenp contains an error code (<0):
684 *		-FDT_ERR_NOTFOUND, node does not have named property
685 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
686 *			tag
687 *		-FDT_ERR_BADMAGIC,
688 *		-FDT_ERR_BADVERSION,
689 *		-FDT_ERR_BADSTATE,
690 *		-FDT_ERR_BADSTRUCTURE,
691 *		-FDT_ERR_TRUNCATED, standard meanings
692 */
693const void *fdt_getprop(const void *fdt, int nodeoffset,
694			const char *name, int *lenp);
695static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
696				  const char *name, int *lenp)
697{
698	return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
699}
700
701/**
702 * fdt_get_phandle - retrieve the phandle of a given node
703 * @fdt: pointer to the device tree blob
704 * @nodeoffset: structure block offset of the node
705 *
706 * fdt_get_phandle() retrieves the phandle of the device tree node at
707 * structure block offset nodeoffset.
708 *
709 * returns:
710 *	the phandle of the node at nodeoffset, on success (!= 0, != -1)
711 *	0, if the node has no phandle, or another error occurs
712 */
713uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
714
715/**
716 * fdt_get_alias_namelen - get alias based on substring
717 * @fdt: pointer to the device tree blob
718 * @name: name of the alias th look up
719 * @namelen: number of characters of name to consider
720 *
721 * Identical to fdt_get_alias(), but only examine the first namelen
722 * characters of name for matching the alias name.
723 */
724#ifndef SWIG /* Not available in Python */
725const char *fdt_get_alias_namelen(const void *fdt,
726				  const char *name, int namelen);
727#endif
728
729/**
730 * fdt_get_alias - retrieve the path referenced by a given alias
731 * @fdt: pointer to the device tree blob
732 * @name: name of the alias th look up
733 *
734 * fdt_get_alias() retrieves the value of a given alias.  That is, the
735 * value of the property named 'name' in the node /aliases.
736 *
737 * returns:
738 *	a pointer to the expansion of the alias named 'name', if it exists
739 *	NULL, if the given alias or the /aliases node does not exist
740 */
741const char *fdt_get_alias(const void *fdt, const char *name);
742
743/**
744 * fdt_get_path - determine the full path of a node
745 * @fdt: pointer to the device tree blob
746 * @nodeoffset: offset of the node whose path to find
747 * @buf: character buffer to contain the returned path (will be overwritten)
748 * @buflen: size of the character buffer at buf
749 *
750 * fdt_get_path() computes the full path of the node at offset
751 * nodeoffset, and records that path in the buffer at buf.
752 *
753 * NOTE: This function is expensive, as it must scan the device tree
754 * structure from the start to nodeoffset.
755 *
756 * returns:
757 *	0, on success
758 *		buf contains the absolute path of the node at
759 *		nodeoffset, as a NUL-terminated string.
760 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
761 *	-FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
762 *		characters and will not fit in the given buffer.
763 *	-FDT_ERR_BADMAGIC,
764 *	-FDT_ERR_BADVERSION,
765 *	-FDT_ERR_BADSTATE,
766 *	-FDT_ERR_BADSTRUCTURE, standard meanings
767 */
768int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
769
770/**
771 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
772 * @fdt: pointer to the device tree blob
773 * @nodeoffset: offset of the node whose parent to find
774 * @supernodedepth: depth of the ancestor to find
775 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
776 *
777 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
778 * at a specific depth from the root (where the root itself has depth
779 * 0, its immediate subnodes depth 1 and so forth).  So
780 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
781 * will always return 0, the offset of the root node.  If the node at
782 * nodeoffset has depth D, then:
783 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
784 * will return nodeoffset itself.
785 *
786 * NOTE: This function is expensive, as it must scan the device tree
787 * structure from the start to nodeoffset.
788 *
789 * returns:
790 *	structure block offset of the node at node offset's ancestor
791 *		of depth supernodedepth (>=0), on success
792 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
793 *	-FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of
794 *		nodeoffset
795 *	-FDT_ERR_BADMAGIC,
796 *	-FDT_ERR_BADVERSION,
797 *	-FDT_ERR_BADSTATE,
798 *	-FDT_ERR_BADSTRUCTURE, standard meanings
799 */
800int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
801				 int supernodedepth, int *nodedepth);
802
803/**
804 * fdt_node_depth - find the depth of a given node
805 * @fdt: pointer to the device tree blob
806 * @nodeoffset: offset of the node whose parent to find
807 *
808 * fdt_node_depth() finds the depth of a given node.  The root node
809 * has depth 0, its immediate subnodes depth 1 and so forth.
810 *
811 * NOTE: This function is expensive, as it must scan the device tree
812 * structure from the start to nodeoffset.
813 *
814 * returns:
815 *	depth of the node at nodeoffset (>=0), on success
816 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
817 *	-FDT_ERR_BADMAGIC,
818 *	-FDT_ERR_BADVERSION,
819 *	-FDT_ERR_BADSTATE,
820 *	-FDT_ERR_BADSTRUCTURE, standard meanings
821 */
822int fdt_node_depth(const void *fdt, int nodeoffset);
823
824/**
825 * fdt_parent_offset - find the parent of a given node
826 * @fdt: pointer to the device tree blob
827 * @nodeoffset: offset of the node whose parent to find
828 *
829 * fdt_parent_offset() locates the parent node of a given node (that
830 * is, it finds the offset of the node which contains the node at
831 * nodeoffset as a subnode).
832 *
833 * NOTE: This function is expensive, as it must scan the device tree
834 * structure from the start to nodeoffset, *twice*.
835 *
836 * returns:
837 *	structure block offset of the parent of the node at nodeoffset
838 *		(>=0), on success
839 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
840 *	-FDT_ERR_BADMAGIC,
841 *	-FDT_ERR_BADVERSION,
842 *	-FDT_ERR_BADSTATE,
843 *	-FDT_ERR_BADSTRUCTURE, standard meanings
844 */
845int fdt_parent_offset(const void *fdt, int nodeoffset);
846
847/**
848 * fdt_node_offset_by_prop_value - find nodes with a given property value
849 * @fdt: pointer to the device tree blob
850 * @startoffset: only find nodes after this offset
851 * @propname: property name to check
852 * @propval: property value to search for
853 * @proplen: length of the value in propval
854 *
855 * fdt_node_offset_by_prop_value() returns the offset of the first
856 * node after startoffset, which has a property named propname whose
857 * value is of length proplen and has value equal to propval; or if
858 * startoffset is -1, the very first such node in the tree.
859 *
860 * To iterate through all nodes matching the criterion, the following
861 * idiom can be used:
862 *	offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
863 *					       propval, proplen);
864 *	while (offset != -FDT_ERR_NOTFOUND) {
865 *		// other code here
866 *		offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
867 *						       propval, proplen);
868 *	}
869 *
870 * Note the -1 in the first call to the function, if 0 is used here
871 * instead, the function will never locate the root node, even if it
872 * matches the criterion.
873 *
874 * returns:
875 *	structure block offset of the located node (>= 0, >startoffset),
876 *		 on success
877 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
878 *		tree after startoffset
879 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
880 *	-FDT_ERR_BADMAGIC,
881 *	-FDT_ERR_BADVERSION,
882 *	-FDT_ERR_BADSTATE,
883 *	-FDT_ERR_BADSTRUCTURE, standard meanings
884 */
885int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
886				  const char *propname,
887				  const void *propval, int proplen);
888
889/**
890 * fdt_node_offset_by_phandle - find the node with a given phandle
891 * @fdt: pointer to the device tree blob
892 * @phandle: phandle value
893 *
894 * fdt_node_offset_by_phandle() returns the offset of the node
895 * which has the given phandle value.  If there is more than one node
896 * in the tree with the given phandle (an invalid tree), results are
897 * undefined.
898 *
899 * returns:
900 *	structure block offset of the located node (>= 0), on success
901 *	-FDT_ERR_NOTFOUND, no node with that phandle exists
902 *	-FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
903 *	-FDT_ERR_BADMAGIC,
904 *	-FDT_ERR_BADVERSION,
905 *	-FDT_ERR_BADSTATE,
906 *	-FDT_ERR_BADSTRUCTURE, standard meanings
907 */
908int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
909
910/**
911 * fdt_node_check_compatible: check a node's compatible property
912 * @fdt: pointer to the device tree blob
913 * @nodeoffset: offset of a tree node
914 * @compatible: string to match against
915 *
916 *
917 * fdt_node_check_compatible() returns 0 if the given node contains a
918 * 'compatible' property with the given string as one of its elements,
919 * it returns non-zero otherwise, or on error.
920 *
921 * returns:
922 *	0, if the node has a 'compatible' property listing the given string
923 *	1, if the node has a 'compatible' property, but it does not list
924 *		the given string
925 *	-FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
926 *	-FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
927 *	-FDT_ERR_BADMAGIC,
928 *	-FDT_ERR_BADVERSION,
929 *	-FDT_ERR_BADSTATE,
930 *	-FDT_ERR_BADSTRUCTURE, standard meanings
931 */
932int fdt_node_check_compatible(const void *fdt, int nodeoffset,
933			      const char *compatible);
934
935/**
936 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
937 * @fdt: pointer to the device tree blob
938 * @startoffset: only find nodes after this offset
939 * @compatible: 'compatible' string to match against
940 *
941 * fdt_node_offset_by_compatible() returns the offset of the first
942 * node after startoffset, which has a 'compatible' property which
943 * lists the given compatible string; or if startoffset is -1, the
944 * very first such node in the tree.
945 *
946 * To iterate through all nodes matching the criterion, the following
947 * idiom can be used:
948 *	offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
949 *	while (offset != -FDT_ERR_NOTFOUND) {
950 *		// other code here
951 *		offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
952 *	}
953 *
954 * Note the -1 in the first call to the function, if 0 is used here
955 * instead, the function will never locate the root node, even if it
956 * matches the criterion.
957 *
958 * returns:
959 *	structure block offset of the located node (>= 0, >startoffset),
960 *		 on success
961 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
962 *		tree after startoffset
963 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
964 *	-FDT_ERR_BADMAGIC,
965 *	-FDT_ERR_BADVERSION,
966 *	-FDT_ERR_BADSTATE,
967 *	-FDT_ERR_BADSTRUCTURE, standard meanings
968 */
969int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
970				  const char *compatible);
971
972/**
973 * fdt_stringlist_contains - check a string list property for a string
974 * @strlist: Property containing a list of strings to check
975 * @listlen: Length of property
976 * @str: String to search for
977 *
978 * This is a utility function provided for convenience. The list contains
979 * one or more strings, each terminated by \0, as is found in a device tree
980 * "compatible" property.
981 *
982 * @return: 1 if the string is found in the list, 0 not found, or invalid list
983 */
984int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
985
986/**
987 * fdt_stringlist_count - count the number of strings in a string list
988 * @fdt: pointer to the device tree blob
989 * @nodeoffset: offset of a tree node
990 * @property: name of the property containing the string list
991 * @return:
992 *   the number of strings in the given property
993 *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
994 *   -FDT_ERR_NOTFOUND if the property does not exist
995 */
996int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property);
997
998/**
999 * fdt_stringlist_search - find a string in a string list and return its index
1000 * @fdt: pointer to the device tree blob
1001 * @nodeoffset: offset of a tree node
1002 * @property: name of the property containing the string list
1003 * @string: string to look up in the string list
1004 *
1005 * Note that it is possible for this function to succeed on property values
1006 * that are not NUL-terminated. That's because the function will stop after
1007 * finding the first occurrence of @string. This can for example happen with
1008 * small-valued cell properties, such as #address-cells, when searching for
1009 * the empty string.
1010 *
1011 * @return:
1012 *   the index of the string in the list of strings
1013 *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1014 *   -FDT_ERR_NOTFOUND if the property does not exist or does not contain
1015 *                     the given string
1016 */
1017int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
1018			  const char *string);
1019
1020/**
1021 * fdt_stringlist_get() - obtain the string at a given index in a string list
1022 * @fdt: pointer to the device tree blob
1023 * @nodeoffset: offset of a tree node
1024 * @property: name of the property containing the string list
1025 * @index: index of the string to return
1026 * @lenp: return location for the string length or an error code on failure
1027 *
1028 * Note that this will successfully extract strings from properties with
1029 * non-NUL-terminated values. For example on small-valued cell properties
1030 * this function will return the empty string.
1031 *
1032 * If non-NULL, the length of the string (on success) or a negative error-code
1033 * (on failure) will be stored in the integer pointer to by lenp.
1034 *
1035 * @return:
1036 *   A pointer to the string at the given index in the string list or NULL on
1037 *   failure. On success the length of the string will be stored in the memory
1038 *   location pointed to by the lenp parameter, if non-NULL. On failure one of
1039 *   the following negative error codes will be returned in the lenp parameter
1040 *   (if non-NULL):
1041 *     -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1042 *     -FDT_ERR_NOTFOUND if the property does not exist
1043 */
1044const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
1045			       const char *property, int index,
1046			       int *lenp);
1047
1048/**********************************************************************/
1049/* Read-only functions (addressing related)                           */
1050/**********************************************************************/
1051
1052/**
1053 * FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells
1054 *
1055 * This is the maximum value for #address-cells, #size-cells and
1056 * similar properties that will be processed by libfdt.  IEE1275
1057 * requires that OF implementations handle values up to 4.
1058 * Implementations may support larger values, but in practice higher
1059 * values aren't used.
1060 */
1061#define FDT_MAX_NCELLS		4
1062
1063/**
1064 * fdt_address_cells - retrieve address size for a bus represented in the tree
1065 * @fdt: pointer to the device tree blob
1066 * @nodeoffset: offset of the node to find the address size for
1067 *
1068 * When the node has a valid #address-cells property, returns its value.
1069 *
1070 * returns:
1071 *	0 <= n < FDT_MAX_NCELLS, on success
1072 *      2, if the node has no #address-cells property
1073 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1074 *		#address-cells property
1075 *	-FDT_ERR_BADMAGIC,
1076 *	-FDT_ERR_BADVERSION,
1077 *	-FDT_ERR_BADSTATE,
1078 *	-FDT_ERR_BADSTRUCTURE,
1079 *	-FDT_ERR_TRUNCATED, standard meanings
1080 */
1081int fdt_address_cells(const void *fdt, int nodeoffset);
1082
1083/**
1084 * fdt_size_cells - retrieve address range size for a bus represented in the
1085 *                  tree
1086 * @fdt: pointer to the device tree blob
1087 * @nodeoffset: offset of the node to find the address range size for
1088 *
1089 * When the node has a valid #size-cells property, returns its value.
1090 *
1091 * returns:
1092 *	0 <= n < FDT_MAX_NCELLS, on success
1093 *      2, if the node has no #address-cells property
1094 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1095 *		#size-cells property
1096 *	-FDT_ERR_BADMAGIC,
1097 *	-FDT_ERR_BADVERSION,
1098 *	-FDT_ERR_BADSTATE,
1099 *	-FDT_ERR_BADSTRUCTURE,
1100 *	-FDT_ERR_TRUNCATED, standard meanings
1101 */
1102int fdt_size_cells(const void *fdt, int nodeoffset);
1103
1104
1105/**********************************************************************/
1106/* Write-in-place functions                                           */
1107/**********************************************************************/
1108
1109/**
1110 * fdt_setprop_inplace_namelen_partial - change a property's value,
1111 *                                       but not its size
1112 * @fdt: pointer to the device tree blob
1113 * @nodeoffset: offset of the node whose property to change
1114 * @name: name of the property to change
1115 * @namelen: number of characters of name to consider
1116 * @idx: index of the property to change in the array
1117 * @val: pointer to data to replace the property value with
1118 * @len: length of the property value
1119 *
1120 * Identical to fdt_setprop_inplace(), but modifies the given property
1121 * starting from the given index, and using only the first characters
1122 * of the name. It is useful when you want to manipulate only one value of
1123 * an array and you have a string that doesn't end with \0.
1124 */
1125#ifndef SWIG /* Not available in Python */
1126int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
1127					const char *name, int namelen,
1128					uint32_t idx, const void *val,
1129					int len);
1130#endif
1131
1132/**
1133 * fdt_setprop_inplace - change a property's value, but not its size
1134 * @fdt: pointer to the device tree blob
1135 * @nodeoffset: offset of the node whose property to change
1136 * @name: name of the property to change
1137 * @val: pointer to data to replace the property value with
1138 * @len: length of the property value
1139 *
1140 * fdt_setprop_inplace() replaces the value of a given property with
1141 * the data in val, of length len.  This function cannot change the
1142 * size of a property, and so will only work if len is equal to the
1143 * current length of the property.
1144 *
1145 * This function will alter only the bytes in the blob which contain
1146 * the given property value, and will not alter or move any other part
1147 * of the tree.
1148 *
1149 * returns:
1150 *	0, on success
1151 *	-FDT_ERR_NOSPACE, if len is not equal to the property's current length
1152 *	-FDT_ERR_NOTFOUND, node does not have the named property
1153 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1154 *	-FDT_ERR_BADMAGIC,
1155 *	-FDT_ERR_BADVERSION,
1156 *	-FDT_ERR_BADSTATE,
1157 *	-FDT_ERR_BADSTRUCTURE,
1158 *	-FDT_ERR_TRUNCATED, standard meanings
1159 */
1160#ifndef SWIG /* Not available in Python */
1161int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
1162			const void *val, int len);
1163#endif
1164
1165/**
1166 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
1167 * @fdt: pointer to the device tree blob
1168 * @nodeoffset: offset of the node whose property to change
1169 * @name: name of the property to change
1170 * @val: 32-bit integer value to replace the property with
1171 *
1172 * fdt_setprop_inplace_u32() replaces the value of a given property
1173 * with the 32-bit integer value in val, converting val to big-endian
1174 * if necessary.  This function cannot change the size of a property,
1175 * and so will only work if the property already exists and has length
1176 * 4.
1177 *
1178 * This function will alter only the bytes in the blob which contain
1179 * the given property value, and will not alter or move any other part
1180 * of the tree.
1181 *
1182 * returns:
1183 *	0, on success
1184 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 4
1185 *	-FDT_ERR_NOTFOUND, node does not have the named property
1186 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1187 *	-FDT_ERR_BADMAGIC,
1188 *	-FDT_ERR_BADVERSION,
1189 *	-FDT_ERR_BADSTATE,
1190 *	-FDT_ERR_BADSTRUCTURE,
1191 *	-FDT_ERR_TRUNCATED, standard meanings
1192 */
1193static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
1194					  const char *name, uint32_t val)
1195{
1196	fdt32_t tmp = cpu_to_fdt32(val);
1197	return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1198}
1199
1200/**
1201 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
1202 * @fdt: pointer to the device tree blob
1203 * @nodeoffset: offset of the node whose property to change
1204 * @name: name of the property to change
1205 * @val: 64-bit integer value to replace the property with
1206 *
1207 * fdt_setprop_inplace_u64() replaces the value of a given property
1208 * with the 64-bit integer value in val, converting val to big-endian
1209 * if necessary.  This function cannot change the size of a property,
1210 * and so will only work if the property already exists and has length
1211 * 8.
1212 *
1213 * This function will alter only the bytes in the blob which contain
1214 * the given property value, and will not alter or move any other part
1215 * of the tree.
1216 *
1217 * returns:
1218 *	0, on success
1219 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 8
1220 *	-FDT_ERR_NOTFOUND, node does not have the named property
1221 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1222 *	-FDT_ERR_BADMAGIC,
1223 *	-FDT_ERR_BADVERSION,
1224 *	-FDT_ERR_BADSTATE,
1225 *	-FDT_ERR_BADSTRUCTURE,
1226 *	-FDT_ERR_TRUNCATED, standard meanings
1227 */
1228static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
1229					  const char *name, uint64_t val)
1230{
1231	fdt64_t tmp = cpu_to_fdt64(val);
1232	return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1233}
1234
1235/**
1236 * fdt_setprop_inplace_cell - change the value of a single-cell property
1237 *
1238 * This is an alternative name for fdt_setprop_inplace_u32()
1239 */
1240static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
1241					   const char *name, uint32_t val)
1242{
1243	return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
1244}
1245
1246/**
1247 * fdt_nop_property - replace a property with nop tags
1248 * @fdt: pointer to the device tree blob
1249 * @nodeoffset: offset of the node whose property to nop
1250 * @name: name of the property to nop
1251 *
1252 * fdt_nop_property() will replace a given property's representation
1253 * in the blob with FDT_NOP tags, effectively removing it from the
1254 * tree.
1255 *
1256 * This function will alter only the bytes in the blob which contain
1257 * the property, and will not alter or move any other part of the
1258 * tree.
1259 *
1260 * returns:
1261 *	0, on success
1262 *	-FDT_ERR_NOTFOUND, node does not have the named property
1263 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1264 *	-FDT_ERR_BADMAGIC,
1265 *	-FDT_ERR_BADVERSION,
1266 *	-FDT_ERR_BADSTATE,
1267 *	-FDT_ERR_BADSTRUCTURE,
1268 *	-FDT_ERR_TRUNCATED, standard meanings
1269 */
1270int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
1271
1272/**
1273 * fdt_nop_node - replace a node (subtree) with nop tags
1274 * @fdt: pointer to the device tree blob
1275 * @nodeoffset: offset of the node to nop
1276 *
1277 * fdt_nop_node() will replace a given node's representation in the
1278 * blob, including all its subnodes, if any, with FDT_NOP tags,
1279 * effectively removing it from the tree.
1280 *
1281 * This function will alter only the bytes in the blob which contain
1282 * the node and its properties and subnodes, and will not alter or
1283 * move any other part of the tree.
1284 *
1285 * returns:
1286 *	0, on success
1287 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1288 *	-FDT_ERR_BADMAGIC,
1289 *	-FDT_ERR_BADVERSION,
1290 *	-FDT_ERR_BADSTATE,
1291 *	-FDT_ERR_BADSTRUCTURE,
1292 *	-FDT_ERR_TRUNCATED, standard meanings
1293 */
1294int fdt_nop_node(void *fdt, int nodeoffset);
1295
1296/**********************************************************************/
1297/* Sequential write functions                                         */
1298/**********************************************************************/
1299
1300int fdt_create(void *buf, int bufsize);
1301int fdt_resize(void *fdt, void *buf, int bufsize);
1302int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
1303int fdt_finish_reservemap(void *fdt);
1304int fdt_begin_node(void *fdt, const char *name);
1305int fdt_property(void *fdt, const char *name, const void *val, int len);
1306static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
1307{
1308	fdt32_t tmp = cpu_to_fdt32(val);
1309	return fdt_property(fdt, name, &tmp, sizeof(tmp));
1310}
1311static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
1312{
1313	fdt64_t tmp = cpu_to_fdt64(val);
1314	return fdt_property(fdt, name, &tmp, sizeof(tmp));
1315}
1316static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
1317{
1318	return fdt_property_u32(fdt, name, val);
1319}
1320
1321/**
1322 * fdt_property_placeholder - add a new property and return a ptr to its value
1323 *
1324 * @fdt: pointer to the device tree blob
1325 * @name: name of property to add
1326 * @len: length of property value in bytes
1327 * @valp: returns a pointer to where where the value should be placed
1328 *
1329 * returns:
1330 *	0, on success
1331 *	-FDT_ERR_BADMAGIC,
1332 *	-FDT_ERR_NOSPACE, standard meanings
1333 */
1334int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp);
1335
1336#define fdt_property_string(fdt, name, str) \
1337	fdt_property(fdt, name, str, strlen(str)+1)
1338int fdt_end_node(void *fdt);
1339int fdt_finish(void *fdt);
1340
1341/**********************************************************************/
1342/* Read-write functions                                               */
1343/**********************************************************************/
1344
1345int fdt_create_empty_tree(void *buf, int bufsize);
1346int fdt_open_into(const void *fdt, void *buf, int bufsize);
1347int fdt_pack(void *fdt);
1348
1349/**
1350 * fdt_add_mem_rsv - add one memory reserve map entry
1351 * @fdt: pointer to the device tree blob
1352 * @address, @size: 64-bit values (native endian)
1353 *
1354 * Adds a reserve map entry to the given blob reserving a region at
1355 * address address of length size.
1356 *
1357 * This function will insert data into the reserve map and will
1358 * therefore change the indexes of some entries in the table.
1359 *
1360 * returns:
1361 *	0, on success
1362 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1363 *		contain the new reservation entry
1364 *	-FDT_ERR_BADMAGIC,
1365 *	-FDT_ERR_BADVERSION,
1366 *	-FDT_ERR_BADSTATE,
1367 *	-FDT_ERR_BADSTRUCTURE,
1368 *	-FDT_ERR_BADLAYOUT,
1369 *	-FDT_ERR_TRUNCATED, standard meanings
1370 */
1371int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
1372
1373/**
1374 * fdt_del_mem_rsv - remove a memory reserve map entry
1375 * @fdt: pointer to the device tree blob
1376 * @n: entry to remove
1377 *
1378 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
1379 * the blob.
1380 *
1381 * This function will delete data from the reservation table and will
1382 * therefore change the indexes of some entries in the table.
1383 *
1384 * returns:
1385 *	0, on success
1386 *	-FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
1387 *		are less than n+1 reserve map entries)
1388 *	-FDT_ERR_BADMAGIC,
1389 *	-FDT_ERR_BADVERSION,
1390 *	-FDT_ERR_BADSTATE,
1391 *	-FDT_ERR_BADSTRUCTURE,
1392 *	-FDT_ERR_BADLAYOUT,
1393 *	-FDT_ERR_TRUNCATED, standard meanings
1394 */
1395int fdt_del_mem_rsv(void *fdt, int n);
1396
1397/**
1398 * fdt_set_name - change the name of a given node
1399 * @fdt: pointer to the device tree blob
1400 * @nodeoffset: structure block offset of a node
1401 * @name: name to give the node
1402 *
1403 * fdt_set_name() replaces the name (including unit address, if any)
1404 * of the given node with the given string.  NOTE: this function can't
1405 * efficiently check if the new name is unique amongst the given
1406 * node's siblings; results are undefined if this function is invoked
1407 * with a name equal to one of the given node's siblings.
1408 *
1409 * This function may insert or delete data from the blob, and will
1410 * therefore change the offsets of some existing nodes.
1411 *
1412 * returns:
1413 *	0, on success
1414 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob
1415 *		to contain the new name
1416 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1417 *	-FDT_ERR_BADMAGIC,
1418 *	-FDT_ERR_BADVERSION,
1419 *	-FDT_ERR_BADSTATE, standard meanings
1420 */
1421int fdt_set_name(void *fdt, int nodeoffset, const char *name);
1422
1423/**
1424 * fdt_setprop - create or change a property
1425 * @fdt: pointer to the device tree blob
1426 * @nodeoffset: offset of the node whose property to change
1427 * @name: name of the property to change
1428 * @val: pointer to data to set the property value to
1429 * @len: length of the property value
1430 *
1431 * fdt_setprop() sets the value of the named property in the given
1432 * node to the given value and length, creating the property if it
1433 * does not already exist.
1434 *
1435 * This function may insert or delete data from the blob, and will
1436 * therefore change the offsets of some existing nodes.
1437 *
1438 * returns:
1439 *	0, on success
1440 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1441 *		contain the new property value
1442 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1443 *	-FDT_ERR_BADLAYOUT,
1444 *	-FDT_ERR_BADMAGIC,
1445 *	-FDT_ERR_BADVERSION,
1446 *	-FDT_ERR_BADSTATE,
1447 *	-FDT_ERR_BADSTRUCTURE,
1448 *	-FDT_ERR_BADLAYOUT,
1449 *	-FDT_ERR_TRUNCATED, standard meanings
1450 */
1451int fdt_setprop(void *fdt, int nodeoffset, const char *name,
1452		const void *val, int len);
1453
1454/**
1455 * fdt_setprop_placeholder - allocate space for a property
1456 * @fdt: pointer to the device tree blob
1457 * @nodeoffset: offset of the node whose property to change
1458 * @name: name of the property to change
1459 * @len: length of the property value
1460 * @prop_data: return pointer to property data
1461 *
1462 * fdt_setprop_placeholer() allocates the named property in the given node.
1463 * If the property exists it is resized. In either case a pointer to the
1464 * property data is returned.
1465 *
1466 * This function may insert or delete data from the blob, and will
1467 * therefore change the offsets of some existing nodes.
1468 *
1469 * returns:
1470 *	0, on success
1471 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1472 *		contain the new property value
1473 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1474 *	-FDT_ERR_BADLAYOUT,
1475 *	-FDT_ERR_BADMAGIC,
1476 *	-FDT_ERR_BADVERSION,
1477 *	-FDT_ERR_BADSTATE,
1478 *	-FDT_ERR_BADSTRUCTURE,
1479 *	-FDT_ERR_BADLAYOUT,
1480 *	-FDT_ERR_TRUNCATED, standard meanings
1481 */
1482int fdt_setprop_placeholder(void *fdt, int nodeoffset, const char *name,
1483			    int len, void **prop_data);
1484
1485/**
1486 * fdt_setprop_u32 - set a property to a 32-bit integer
1487 * @fdt: pointer to the device tree blob
1488 * @nodeoffset: offset of the node whose property to change
1489 * @name: name of the property to change
1490 * @val: 32-bit integer value for the property (native endian)
1491 *
1492 * fdt_setprop_u32() sets the value of the named property in the given
1493 * node to the given 32-bit integer value (converting to big-endian if
1494 * necessary), or creates a new property with that value if it does
1495 * not already exist.
1496 *
1497 * This function may insert or delete data from the blob, and will
1498 * therefore change the offsets of some existing nodes.
1499 *
1500 * returns:
1501 *	0, on success
1502 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1503 *		contain the new property value
1504 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1505 *	-FDT_ERR_BADLAYOUT,
1506 *	-FDT_ERR_BADMAGIC,
1507 *	-FDT_ERR_BADVERSION,
1508 *	-FDT_ERR_BADSTATE,
1509 *	-FDT_ERR_BADSTRUCTURE,
1510 *	-FDT_ERR_BADLAYOUT,
1511 *	-FDT_ERR_TRUNCATED, standard meanings
1512 */
1513static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
1514				  uint32_t val)
1515{
1516	fdt32_t tmp = cpu_to_fdt32(val);
1517	return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1518}
1519
1520/**
1521 * fdt_setprop_u64 - set a property to a 64-bit integer
1522 * @fdt: pointer to the device tree blob
1523 * @nodeoffset: offset of the node whose property to change
1524 * @name: name of the property to change
1525 * @val: 64-bit integer value for the property (native endian)
1526 *
1527 * fdt_setprop_u64() sets the value of the named property in the given
1528 * node to the given 64-bit integer value (converting to big-endian if
1529 * necessary), or creates a new property with that value if it does
1530 * not already exist.
1531 *
1532 * This function may insert or delete data from the blob, and will
1533 * therefore change the offsets of some existing nodes.
1534 *
1535 * returns:
1536 *	0, on success
1537 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1538 *		contain the new property value
1539 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1540 *	-FDT_ERR_BADLAYOUT,
1541 *	-FDT_ERR_BADMAGIC,
1542 *	-FDT_ERR_BADVERSION,
1543 *	-FDT_ERR_BADSTATE,
1544 *	-FDT_ERR_BADSTRUCTURE,
1545 *	-FDT_ERR_BADLAYOUT,
1546 *	-FDT_ERR_TRUNCATED, standard meanings
1547 */
1548static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
1549				  uint64_t val)
1550{
1551	fdt64_t tmp = cpu_to_fdt64(val);
1552	return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1553}
1554
1555/**
1556 * fdt_setprop_cell - set a property to a single cell value
1557 *
1558 * This is an alternative name for fdt_setprop_u32()
1559 */
1560static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
1561				   uint32_t val)
1562{
1563	return fdt_setprop_u32(fdt, nodeoffset, name, val);
1564}
1565
1566/**
1567 * fdt_setprop_string - set a property to a string value
1568 * @fdt: pointer to the device tree blob
1569 * @nodeoffset: offset of the node whose property to change
1570 * @name: name of the property to change
1571 * @str: string value for the property
1572 *
1573 * fdt_setprop_string() sets the value of the named property in the
1574 * given node to the given string value (using the length of the
1575 * string to determine the new length of the property), or creates a
1576 * new property with that value if it does not already exist.
1577 *
1578 * This function may insert or delete data from the blob, and will
1579 * therefore change the offsets of some existing nodes.
1580 *
1581 * returns:
1582 *	0, on success
1583 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1584 *		contain the new property value
1585 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1586 *	-FDT_ERR_BADLAYOUT,
1587 *	-FDT_ERR_BADMAGIC,
1588 *	-FDT_ERR_BADVERSION,
1589 *	-FDT_ERR_BADSTATE,
1590 *	-FDT_ERR_BADSTRUCTURE,
1591 *	-FDT_ERR_BADLAYOUT,
1592 *	-FDT_ERR_TRUNCATED, standard meanings
1593 */
1594#define fdt_setprop_string(fdt, nodeoffset, name, str) \
1595	fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1596
1597
1598/**
1599 * fdt_setprop_empty - set a property to an empty value
1600 * @fdt: pointer to the device tree blob
1601 * @nodeoffset: offset of the node whose property to change
1602 * @name: name of the property to change
1603 *
1604 * fdt_setprop_empty() sets the value of the named property in the
1605 * given node to an empty (zero length) value, or creates a new empty
1606 * property if it does not already exist.
1607 *
1608 * This function may insert or delete data from the blob, and will
1609 * therefore change the offsets of some existing nodes.
1610 *
1611 * returns:
1612 *	0, on success
1613 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1614 *		contain the new property value
1615 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1616 *	-FDT_ERR_BADLAYOUT,
1617 *	-FDT_ERR_BADMAGIC,
1618 *	-FDT_ERR_BADVERSION,
1619 *	-FDT_ERR_BADSTATE,
1620 *	-FDT_ERR_BADSTRUCTURE,
1621 *	-FDT_ERR_BADLAYOUT,
1622 *	-FDT_ERR_TRUNCATED, standard meanings
1623 */
1624#define fdt_setprop_empty(fdt, nodeoffset, name) \
1625	fdt_setprop((fdt), (nodeoffset), (name), NULL, 0)
1626
1627/**
1628 * fdt_appendprop - append to or create a property
1629 * @fdt: pointer to the device tree blob
1630 * @nodeoffset: offset of the node whose property to change
1631 * @name: name of the property to append to
1632 * @val: pointer to data to append to the property value
1633 * @len: length of the data to append to the property value
1634 *
1635 * fdt_appendprop() appends the value to the named property in the
1636 * given node, creating the property if it does not already exist.
1637 *
1638 * This function may insert data into the blob, and will therefore
1639 * change the offsets of some existing nodes.
1640 *
1641 * returns:
1642 *	0, on success
1643 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1644 *		contain the new property value
1645 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1646 *	-FDT_ERR_BADLAYOUT,
1647 *	-FDT_ERR_BADMAGIC,
1648 *	-FDT_ERR_BADVERSION,
1649 *	-FDT_ERR_BADSTATE,
1650 *	-FDT_ERR_BADSTRUCTURE,
1651 *	-FDT_ERR_BADLAYOUT,
1652 *	-FDT_ERR_TRUNCATED, standard meanings
1653 */
1654int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
1655		   const void *val, int len);
1656
1657/**
1658 * fdt_appendprop_u32 - append a 32-bit integer value to a property
1659 * @fdt: pointer to the device tree blob
1660 * @nodeoffset: offset of the node whose property to change
1661 * @name: name of the property to change
1662 * @val: 32-bit integer value to append to the property (native endian)
1663 *
1664 * fdt_appendprop_u32() appends the given 32-bit integer value
1665 * (converting to big-endian if necessary) to the value of the named
1666 * property in the given node, or creates a new property with that
1667 * value if it does not already exist.
1668 *
1669 * This function may insert data into the blob, and will therefore
1670 * change the offsets of some existing nodes.
1671 *
1672 * returns:
1673 *	0, on success
1674 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1675 *		contain the new property value
1676 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1677 *	-FDT_ERR_BADLAYOUT,
1678 *	-FDT_ERR_BADMAGIC,
1679 *	-FDT_ERR_BADVERSION,
1680 *	-FDT_ERR_BADSTATE,
1681 *	-FDT_ERR_BADSTRUCTURE,
1682 *	-FDT_ERR_BADLAYOUT,
1683 *	-FDT_ERR_TRUNCATED, standard meanings
1684 */
1685static inline int fdt_appendprop_u32(void *fdt, int nodeoffset,
1686				     const char *name, uint32_t val)
1687{
1688	fdt32_t tmp = cpu_to_fdt32(val);
1689	return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1690}
1691
1692/**
1693 * fdt_appendprop_u64 - append a 64-bit integer value to a property
1694 * @fdt: pointer to the device tree blob
1695 * @nodeoffset: offset of the node whose property to change
1696 * @name: name of the property to change
1697 * @val: 64-bit integer value to append to the property (native endian)
1698 *
1699 * fdt_appendprop_u64() appends the given 64-bit integer value
1700 * (converting to big-endian if necessary) to the value of the named
1701 * property in the given node, or creates a new property with that
1702 * value if it does not already exist.
1703 *
1704 * This function may insert data into the blob, and will therefore
1705 * change the offsets of some existing nodes.
1706 *
1707 * returns:
1708 *	0, on success
1709 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1710 *		contain the new property value
1711 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1712 *	-FDT_ERR_BADLAYOUT,
1713 *	-FDT_ERR_BADMAGIC,
1714 *	-FDT_ERR_BADVERSION,
1715 *	-FDT_ERR_BADSTATE,
1716 *	-FDT_ERR_BADSTRUCTURE,
1717 *	-FDT_ERR_BADLAYOUT,
1718 *	-FDT_ERR_TRUNCATED, standard meanings
1719 */
1720static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
1721				     const char *name, uint64_t val)
1722{
1723	fdt64_t tmp = cpu_to_fdt64(val);
1724	return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1725}
1726
1727/**
1728 * fdt_appendprop_cell - append a single cell value to a property
1729 *
1730 * This is an alternative name for fdt_appendprop_u32()
1731 */
1732static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
1733				      const char *name, uint32_t val)
1734{
1735	return fdt_appendprop_u32(fdt, nodeoffset, name, val);
1736}
1737
1738/**
1739 * fdt_appendprop_string - append a string to a property
1740 * @fdt: pointer to the device tree blob
1741 * @nodeoffset: offset of the node whose property to change
1742 * @name: name of the property to change
1743 * @str: string value to append to the property
1744 *
1745 * fdt_appendprop_string() appends the given string to the value of
1746 * the named property in the given node, or creates a new property
1747 * with that value if it does not already exist.
1748 *
1749 * This function may insert data into the blob, and will therefore
1750 * change the offsets of some existing nodes.
1751 *
1752 * returns:
1753 *	0, on success
1754 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1755 *		contain the new property value
1756 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1757 *	-FDT_ERR_BADLAYOUT,
1758 *	-FDT_ERR_BADMAGIC,
1759 *	-FDT_ERR_BADVERSION,
1760 *	-FDT_ERR_BADSTATE,
1761 *	-FDT_ERR_BADSTRUCTURE,
1762 *	-FDT_ERR_BADLAYOUT,
1763 *	-FDT_ERR_TRUNCATED, standard meanings
1764 */
1765#define fdt_appendprop_string(fdt, nodeoffset, name, str) \
1766	fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1767
1768/**
1769 * fdt_delprop - delete a property
1770 * @fdt: pointer to the device tree blob
1771 * @nodeoffset: offset of the node whose property to nop
1772 * @name: name of the property to nop
1773 *
1774 * fdt_del_property() will delete the given property.
1775 *
1776 * This function will delete data from the blob, and will therefore
1777 * change the offsets of some existing nodes.
1778 *
1779 * returns:
1780 *	0, on success
1781 *	-FDT_ERR_NOTFOUND, node does not have the named property
1782 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1783 *	-FDT_ERR_BADLAYOUT,
1784 *	-FDT_ERR_BADMAGIC,
1785 *	-FDT_ERR_BADVERSION,
1786 *	-FDT_ERR_BADSTATE,
1787 *	-FDT_ERR_BADSTRUCTURE,
1788 *	-FDT_ERR_TRUNCATED, standard meanings
1789 */
1790int fdt_delprop(void *fdt, int nodeoffset, const char *name);
1791
1792/**
1793 * fdt_add_subnode_namelen - creates a new node based on substring
1794 * @fdt: pointer to the device tree blob
1795 * @parentoffset: structure block offset of a node
1796 * @name: name of the subnode to locate
1797 * @namelen: number of characters of name to consider
1798 *
1799 * Identical to fdt_add_subnode(), but use only the first namelen
1800 * characters of name as the name of the new node.  This is useful for
1801 * creating subnodes based on a portion of a larger string, such as a
1802 * full path.
1803 */
1804#ifndef SWIG /* Not available in Python */
1805int fdt_add_subnode_namelen(void *fdt, int parentoffset,
1806			    const char *name, int namelen);
1807#endif
1808
1809/**
1810 * fdt_add_subnode - creates a new node
1811 * @fdt: pointer to the device tree blob
1812 * @parentoffset: structure block offset of a node
1813 * @name: name of the subnode to locate
1814 *
1815 * fdt_add_subnode() creates a new node as a subnode of the node at
1816 * structure block offset parentoffset, with the given name (which
1817 * should include the unit address, if any).
1818 *
1819 * This function will insert data into the blob, and will therefore
1820 * change the offsets of some existing nodes.
1821
1822 * returns:
1823 *	structure block offset of the created nodeequested subnode (>=0), on
1824 *		success
1825 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
1826 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
1827 *		tag
1828 *	-FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
1829 *		the given name
1830 *	-FDT_ERR_NOSPACE, if there is insufficient free space in the
1831 *		blob to contain the new node
1832 *	-FDT_ERR_NOSPACE
1833 *	-FDT_ERR_BADLAYOUT
1834 *      -FDT_ERR_BADMAGIC,
1835 *	-FDT_ERR_BADVERSION,
1836 *	-FDT_ERR_BADSTATE,
1837 *	-FDT_ERR_BADSTRUCTURE,
1838 *	-FDT_ERR_TRUNCATED, standard meanings.
1839 */
1840int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
1841
1842/**
1843 * fdt_del_node - delete a node (subtree)
1844 * @fdt: pointer to the device tree blob
1845 * @nodeoffset: offset of the node to nop
1846 *
1847 * fdt_del_node() will remove the given node, including all its
1848 * subnodes if any, from the blob.
1849 *
1850 * This function will delete data from the blob, and will therefore
1851 * change the offsets of some existing nodes.
1852 *
1853 * returns:
1854 *	0, on success
1855 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1856 *	-FDT_ERR_BADLAYOUT,
1857 *	-FDT_ERR_BADMAGIC,
1858 *	-FDT_ERR_BADVERSION,
1859 *	-FDT_ERR_BADSTATE,
1860 *	-FDT_ERR_BADSTRUCTURE,
1861 *	-FDT_ERR_TRUNCATED, standard meanings
1862 */
1863int fdt_del_node(void *fdt, int nodeoffset);
1864
1865/**
1866 * fdt_overlay_apply - Applies a DT overlay on a base DT
1867 * @fdt: pointer to the base device tree blob
1868 * @fdto: pointer to the device tree overlay blob
1869 *
1870 * fdt_overlay_apply() will apply the given device tree overlay on the
1871 * given base device tree.
1872 *
1873 * Expect the base device tree to be modified, even if the function
1874 * returns an error.
1875 *
1876 * returns:
1877 *	0, on success
1878 *	-FDT_ERR_NOSPACE, there's not enough space in the base device tree
1879 *	-FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
1880 *		properties in the base DT
1881 *	-FDT_ERR_BADPHANDLE,
1882 *	-FDT_ERR_BADOVERLAY,
1883 *	-FDT_ERR_NOPHANDLES,
1884 *	-FDT_ERR_INTERNAL,
1885 *	-FDT_ERR_BADLAYOUT,
1886 *	-FDT_ERR_BADMAGIC,
1887 *	-FDT_ERR_BADOFFSET,
1888 *	-FDT_ERR_BADPATH,
1889 *	-FDT_ERR_BADVERSION,
1890 *	-FDT_ERR_BADSTRUCTURE,
1891 *	-FDT_ERR_BADSTATE,
1892 *	-FDT_ERR_TRUNCATED, standard meanings
1893 */
1894int fdt_overlay_apply(void *fdt, void *fdto);
1895
1896/**********************************************************************/
1897/* Debugging / informational functions                                */
1898/**********************************************************************/
1899
1900const char *fdt_strerror(int errval);
1901
1902#endif /* LIBFDT_H */
1903