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: FDT or a sub-block is improperly
94	 * terminated (overflows, goes outside allowed bounds, or
95	 * isn't properly terminated).  */
96#define FDT_ERR_BADMAGIC	9
97	/* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
98	 * device tree at all - it is missing the flattened device
99	 * tree magic number. */
100#define FDT_ERR_BADVERSION	10
101	/* FDT_ERR_BADVERSION: Given device tree has a version which
102	 * can't be handled by the requested operation.  For
103	 * read-write functions, this may mean that fdt_open_into() is
104	 * required to convert the tree to the expected version. */
105#define FDT_ERR_BADSTRUCTURE	11
106	/* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt
107	 * structure block or other serious error (e.g. misnested
108	 * nodes, or subnodes preceding properties). */
109#define FDT_ERR_BADLAYOUT	12
110	/* FDT_ERR_BADLAYOUT: For read-write functions, the given
111	 * device tree has it's sub-blocks in an order that the
112	 * function can't handle (memory reserve map, then structure,
113	 * then strings).  Use fdt_open_into() to reorganize the tree
114	 * into a form suitable for the read-write operations. */
115
116/* "Can't happen" error indicating a bug in libfdt */
117#define FDT_ERR_INTERNAL	13
118	/* FDT_ERR_INTERNAL: libfdt has failed an internal assertion.
119	 * Should never be returned, if it is, it indicates a bug in
120	 * libfdt itself. */
121
122/* Errors in device tree content */
123#define FDT_ERR_BADNCELLS	14
124	/* FDT_ERR_BADNCELLS: Device tree has a #address-cells, #size-cells
125	 * or similar property with a bad format or value */
126
127#define FDT_ERR_BADVALUE	15
128	/* FDT_ERR_BADVALUE: Device tree has a property with an unexpected
129	 * value. For example: a property expected to contain a string list
130	 * is not NUL-terminated within the length of its value. */
131
132#define FDT_ERR_BADOVERLAY	16
133	/* FDT_ERR_BADOVERLAY: The device tree overlay, while
134	 * correctly structured, cannot be applied due to some
135	 * unexpected or missing value, property or node. */
136
137#define FDT_ERR_NOPHANDLES	17
138	/* FDT_ERR_NOPHANDLES: The device tree doesn't have any
139	 * phandle available anymore without causing an overflow */
140
141#define FDT_ERR_MAX		17
142
143/**********************************************************************/
144/* Low-level functions (you probably don't need these)                */
145/**********************************************************************/
146
147#ifndef SWIG /* This function is not useful in Python */
148const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen);
149#endif
150static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
151{
152	return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
153}
154
155uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
156
157/*
158 * Alignment helpers:
159 *     These helpers access words from a device tree blob.  They're
160 *     built to work even with unaligned pointers on platforms (ike
161 *     ARM) that don't like unaligned loads and stores
162 */
163
164static inline uint32_t fdt32_ld(const fdt32_t *p)
165{
166	fdt32_t v;
167
168	memcpy(&v, p, sizeof(v));
169	return fdt32_to_cpu(v);
170}
171
172static inline uint64_t fdt64_ld(const fdt64_t *p)
173{
174	fdt64_t v;
175
176	memcpy(&v, p, sizeof(v));
177	return fdt64_to_cpu(v);
178}
179
180/**********************************************************************/
181/* Traversal functions                                                */
182/**********************************************************************/
183
184int fdt_next_node(const void *fdt, int offset, int *depth);
185
186/**
187 * fdt_first_subnode() - get offset of first direct subnode
188 *
189 * @fdt:	FDT blob
190 * @offset:	Offset of node to check
191 * @return offset of first subnode, or -FDT_ERR_NOTFOUND if there is none
192 */
193int fdt_first_subnode(const void *fdt, int offset);
194
195/**
196 * fdt_next_subnode() - get offset of next direct subnode
197 *
198 * After first calling fdt_first_subnode(), call this function repeatedly to
199 * get direct subnodes of a parent node.
200 *
201 * @fdt:	FDT blob
202 * @offset:	Offset of previous subnode
203 * @return offset of next subnode, or -FDT_ERR_NOTFOUND if there are no more
204 * subnodes
205 */
206int fdt_next_subnode(const void *fdt, int offset);
207
208/**
209 * fdt_for_each_subnode - iterate over all subnodes of a parent
210 *
211 * @node:	child node (int, lvalue)
212 * @fdt:	FDT blob (const void *)
213 * @parent:	parent node (int)
214 *
215 * This is actually a wrapper around a for loop and would be used like so:
216 *
217 *	fdt_for_each_subnode(node, fdt, parent) {
218 *		Use node
219 *		...
220 *	}
221 *
222 *	if ((node < 0) && (node != -FDT_ERR_NOT_FOUND)) {
223 *		Error handling
224 *	}
225 *
226 * Note that this is implemented as a macro and @node is used as
227 * iterator in the loop. The parent variable be constant or even a
228 * literal.
229 *
230 */
231#define fdt_for_each_subnode(node, fdt, parent)		\
232	for (node = fdt_first_subnode(fdt, parent);	\
233	     node >= 0;					\
234	     node = fdt_next_subnode(fdt, node))
235
236/**********************************************************************/
237/* General functions                                                  */
238/**********************************************************************/
239#define fdt_get_header(fdt, field) \
240	(fdt32_ld(&((const struct fdt_header *)(fdt))->field))
241#define fdt_magic(fdt)			(fdt_get_header(fdt, magic))
242#define fdt_totalsize(fdt)		(fdt_get_header(fdt, totalsize))
243#define fdt_off_dt_struct(fdt)		(fdt_get_header(fdt, off_dt_struct))
244#define fdt_off_dt_strings(fdt)		(fdt_get_header(fdt, off_dt_strings))
245#define fdt_off_mem_rsvmap(fdt)		(fdt_get_header(fdt, off_mem_rsvmap))
246#define fdt_version(fdt)		(fdt_get_header(fdt, version))
247#define fdt_last_comp_version(fdt)	(fdt_get_header(fdt, last_comp_version))
248#define fdt_boot_cpuid_phys(fdt)	(fdt_get_header(fdt, boot_cpuid_phys))
249#define fdt_size_dt_strings(fdt)	(fdt_get_header(fdt, size_dt_strings))
250#define fdt_size_dt_struct(fdt)		(fdt_get_header(fdt, size_dt_struct))
251
252#define fdt_set_hdr_(name) \
253	static inline void fdt_set_##name(void *fdt, uint32_t val) \
254	{ \
255		struct fdt_header *fdth = (struct fdt_header *)fdt; \
256		fdth->name = cpu_to_fdt32(val); \
257	}
258fdt_set_hdr_(magic);
259fdt_set_hdr_(totalsize);
260fdt_set_hdr_(off_dt_struct);
261fdt_set_hdr_(off_dt_strings);
262fdt_set_hdr_(off_mem_rsvmap);
263fdt_set_hdr_(version);
264fdt_set_hdr_(last_comp_version);
265fdt_set_hdr_(boot_cpuid_phys);
266fdt_set_hdr_(size_dt_strings);
267fdt_set_hdr_(size_dt_struct);
268#undef fdt_set_hdr_
269enum display_mode {
270	MODE_SHOW_VALUE,	/* show values for node properties */
271	MODE_LIST_PROPS,	/* list the properties for a node */
272	MODE_LIST_SUBNODES,	/* list the subnodes of a node */
273};
274
275/* Holds information which controls our output and options */
276struct display_info {
277	int type;		/* data type (s/i/u/x or 0 for default) */
278	int size;		/* data size (1/2/4) */
279	enum display_mode mode;	/* display mode that we are using */
280	const char *default_val; /* default value if node/property not found */
281};
282
283/**
284 * fdt_header_size - return the size of the tree's header
285 * @fdt: pointer to a flattened device tree
286 */
287size_t fdt_header_size_(uint32_t version);
288static inline size_t fdt_header_size(const void *fdt)
289{
290	return fdt_header_size_(fdt_version(fdt));
291}
292
293/**
294 * fdt_check_header - sanity check a device tree header
295
296 * @fdt: pointer to data which might be a flattened device tree
297 *
298 * fdt_check_header() checks that the given buffer contains what
299 * appears to be a flattened device tree, and that the header contains
300 * valid information (to the extent that can be determined from the
301 * header alone).
302 *
303 * returns:
304 *     0, if the buffer appears to contain a valid device tree
305 *     -FDT_ERR_BADMAGIC,
306 *     -FDT_ERR_BADVERSION,
307 *     -FDT_ERR_BADSTATE,
308 *     -FDT_ERR_TRUNCATED, standard meanings, as above
309 */
310int fdt_check_header(const void *fdt);
311
312/**
313 * fdt_move - move a device tree around in memory
314 * @fdt: pointer to the device tree to move
315 * @buf: pointer to memory where the device is to be moved
316 * @bufsize: size of the memory space at buf
317 *
318 * fdt_move() relocates, if possible, the device tree blob located at
319 * fdt to the buffer at buf of size bufsize.  The buffer may overlap
320 * with the existing device tree blob at fdt.  Therefore,
321 *     fdt_move(fdt, fdt, fdt_totalsize(fdt))
322 * should always succeed.
323 *
324 * returns:
325 *     0, on success
326 *     -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
327 *     -FDT_ERR_BADMAGIC,
328 *     -FDT_ERR_BADVERSION,
329 *     -FDT_ERR_BADSTATE, standard meanings
330 */
331int fdt_move(const void *fdt, void *buf, int bufsize);
332
333/**********************************************************************/
334/* Read-only functions                                                */
335/**********************************************************************/
336
337int fdt_check_full(const void *fdt, size_t bufsize);
338
339/**
340 * fdt_get_string - retrieve a string from the strings block of a device tree
341 * @fdt: pointer to the device tree blob
342 * @stroffset: offset of the string within the strings block (native endian)
343 * @lenp: optional pointer to return the string's length
344 *
345 * fdt_get_string() retrieves a pointer to a single string from the
346 * strings block of the device tree blob at fdt, and optionally also
347 * returns the string's length in *lenp.
348 *
349 * returns:
350 *     a pointer to the string, on success
351 *     NULL, if stroffset is out of bounds, or doesn't point to a valid string
352 */
353const char *fdt_get_string(const void *fdt, int stroffset, int *lenp);
354
355/**
356 * fdt_string - retrieve a string from the strings block of a device tree
357 * @fdt: pointer to the device tree blob
358 * @stroffset: offset of the string within the strings block (native endian)
359 *
360 * fdt_string() retrieves a pointer to a single string from the
361 * strings block of the device tree blob at fdt.
362 *
363 * returns:
364 *     a pointer to the string, on success
365 *     NULL, if stroffset is out of bounds, or doesn't point to a valid string
366 */
367const char *fdt_string(const void *fdt, int stroffset);
368
369/**
370 * fdt_get_max_phandle - retrieves the highest phandle in a tree
371 * @fdt: pointer to the device tree blob
372 *
373 * fdt_get_max_phandle retrieves the highest phandle in the given
374 * device tree. This will ignore badly formatted phandles, or phandles
375 * with a value of 0 or -1.
376 *
377 * returns:
378 *      the highest phandle on success
379 *      0, if no phandle was found in the device tree
380 *      -1, if an error occurred
381 */
382uint32_t fdt_get_max_phandle(const void *fdt);
383
384/**
385 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
386 * @fdt: pointer to the device tree blob
387 *
388 * Returns the number of entries in the device tree blob's memory
389 * reservation map.  This does not include the terminating 0,0 entry
390 * or any other (0,0) entries reserved for expansion.
391 *
392 * returns:
393 *     the number of entries
394 */
395int fdt_num_mem_rsv(const void *fdt);
396
397/**
398 * fdt_get_mem_rsv - retrieve one memory reserve map entry
399 * @fdt: pointer to the device tree blob
400 * @address, @size: pointers to 64-bit variables
401 *
402 * On success, *address and *size will contain the address and size of
403 * the n-th reserve map entry from the device tree blob, in
404 * native-endian format.
405 *
406 * returns:
407 *     0, on success
408 *     -FDT_ERR_BADMAGIC,
409 *     -FDT_ERR_BADVERSION,
410 *     -FDT_ERR_BADSTATE, standard meanings
411 */
412int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
413
414/**
415 * fdt_subnode_offset_namelen - find a subnode based on substring
416 * @fdt: pointer to the device tree blob
417 * @parentoffset: structure block offset of a node
418 * @name: name of the subnode to locate
419 * @namelen: number of characters of name to consider
420 *
421 * Identical to fdt_subnode_offset(), but only examine the first
422 * namelen characters of name for matching the subnode name.  This is
423 * useful for finding subnodes based on a portion of a larger string,
424 * such as a full path.
425 */
426#ifndef SWIG /* Not available in Python */
427int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
428			       const char *name, int namelen);
429#endif
430/**
431 * fdt_subnode_offset - find a subnode of a given node
432 * @fdt: pointer to the device tree blob
433 * @parentoffset: structure block offset of a node
434 * @name: name of the subnode to locate
435 *
436 * fdt_subnode_offset() finds a subnode of the node at structure block
437 * offset parentoffset with the given name.  name may include a unit
438 * address, in which case fdt_subnode_offset() will find the subnode
439 * with that unit address, or the unit address may be omitted, in
440 * which case fdt_subnode_offset() will find an arbitrary subnode
441 * whose name excluding unit address matches the given name.
442 *
443 * returns:
444 *	structure block offset of the requested subnode (>=0), on success
445 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
446 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
447 *		tag
448 *	-FDT_ERR_BADMAGIC,
449 *	-FDT_ERR_BADVERSION,
450 *	-FDT_ERR_BADSTATE,
451 *	-FDT_ERR_BADSTRUCTURE,
452 *	-FDT_ERR_TRUNCATED, standard meanings.
453 */
454int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
455
456/**
457 * fdt_path_offset_namelen - find a tree node by its full path
458 * @fdt: pointer to the device tree blob
459 * @path: full path of the node to locate
460 * @namelen: number of characters of path to consider
461 *
462 * Identical to fdt_path_offset(), but only consider the first namelen
463 * characters of path as the path name.
464 */
465#ifndef SWIG /* Not available in Python */
466int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen);
467#endif
468
469/**
470 * fdt_path_offset - find a tree node by its full path
471 * @fdt: pointer to the device tree blob
472 * @path: full path of the node to locate
473 *
474 * fdt_path_offset() finds a node of a given path in the device tree.
475 * Each path component may omit the unit address portion, but the
476 * results of this are undefined if any such path component is
477 * ambiguous (that is if there are multiple nodes at the relevant
478 * level matching the given component, differentiated only by unit
479 * address).
480 *
481 * returns:
482 *	structure block offset of the node with the requested path (>=0), on
483 *		success
484 *	-FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
485 *	-FDT_ERR_NOTFOUND, if the requested node does not exist
486 *      -FDT_ERR_BADMAGIC,
487 *	-FDT_ERR_BADVERSION,
488 *	-FDT_ERR_BADSTATE,
489 *	-FDT_ERR_BADSTRUCTURE,
490 *	-FDT_ERR_TRUNCATED, standard meanings.
491 */
492int fdt_path_offset(const void *fdt, const char *path);
493
494/**
495 * fdt_get_name - retrieve the name of a given node
496 * @fdt: pointer to the device tree blob
497 * @nodeoffset: structure block offset of the starting node
498 * @lenp: pointer to an integer variable (will be overwritten) or NULL
499 *
500 * fdt_get_name() retrieves the name (including unit address) of the
501 * device tree node at structure block offset nodeoffset.  If lenp is
502 * non-NULL, the length of this name is also returned, in the integer
503 * pointed to by lenp.
504 *
505 * returns:
506 *	pointer to the node's name, on success
507 *		If lenp is non-NULL, *lenp contains the length of that name
508 *			(>=0)
509 *	NULL, on error
510 *		if lenp is non-NULL *lenp contains an error code (<0):
511 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
512 *			tag
513 *		-FDT_ERR_BADMAGIC,
514 *		-FDT_ERR_BADVERSION,
515 *		-FDT_ERR_BADSTATE, standard meanings
516 */
517const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
518
519/**
520 * fdt_first_property_offset - find the offset of a node's first property
521 * @fdt: pointer to the device tree blob
522 * @nodeoffset: structure block offset of a node
523 *
524 * fdt_first_property_offset() finds the first property of the node at
525 * the given structure block offset.
526 *
527 * returns:
528 *	structure block offset of the property (>=0), on success
529 *	-FDT_ERR_NOTFOUND, if the requested node has no properties
530 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
531 *      -FDT_ERR_BADMAGIC,
532 *	-FDT_ERR_BADVERSION,
533 *	-FDT_ERR_BADSTATE,
534 *	-FDT_ERR_BADSTRUCTURE,
535 *	-FDT_ERR_TRUNCATED, standard meanings.
536 */
537int fdt_first_property_offset(const void *fdt, int nodeoffset);
538
539/**
540 * fdt_next_property_offset - step through a node's properties
541 * @fdt: pointer to the device tree blob
542 * @offset: structure block offset of a property
543 *
544 * fdt_next_property_offset() finds the property immediately after the
545 * one at the given structure block offset.  This will be a property
546 * of the same node as the given property.
547 *
548 * returns:
549 *	structure block offset of the next property (>=0), on success
550 *	-FDT_ERR_NOTFOUND, if the given property is the last in its node
551 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag
552 *      -FDT_ERR_BADMAGIC,
553 *	-FDT_ERR_BADVERSION,
554 *	-FDT_ERR_BADSTATE,
555 *	-FDT_ERR_BADSTRUCTURE,
556 *	-FDT_ERR_TRUNCATED, standard meanings.
557 */
558int fdt_next_property_offset(const void *fdt, int offset);
559
560/**
561 * fdt_for_each_property_offset - iterate over all properties of a node
562 *
563 * @property_offset:	property offset (int, lvalue)
564 * @fdt:		FDT blob (const void *)
565 * @node:		node offset (int)
566 *
567 * This is actually a wrapper around a for loop and would be used like so:
568 *
569 *	fdt_for_each_property_offset(property, fdt, node) {
570 *		Use property
571 *		...
572 *	}
573 *
574 *	if ((property < 0) && (property != -FDT_ERR_NOT_FOUND)) {
575 *		Error handling
576 *	}
577 *
578 * Note that this is implemented as a macro and property is used as
579 * iterator in the loop. The node variable can be constant or even a
580 * literal.
581 */
582#define fdt_for_each_property_offset(property, fdt, node)	\
583	for (property = fdt_first_property_offset(fdt, node);	\
584	     property >= 0;					\
585	     property = fdt_next_property_offset(fdt, property))
586
587/**
588 * fdt_get_property_by_offset - retrieve the property at a given offset
589 * @fdt: pointer to the device tree blob
590 * @offset: offset of the property to retrieve
591 * @lenp: pointer to an integer variable (will be overwritten) or NULL
592 *
593 * fdt_get_property_by_offset() retrieves a pointer to the
594 * fdt_property structure within the device tree blob at the given
595 * offset.  If lenp is non-NULL, the length of the property value is
596 * also returned, in the integer pointed to by lenp.
597 *
598 * Note that this code only works on device tree versions >= 16. fdt_getprop()
599 * works on all versions.
600 *
601 * returns:
602 *	pointer to the structure representing the property
603 *		if lenp is non-NULL, *lenp contains the length of the property
604 *		value (>=0)
605 *	NULL, on error
606 *		if lenp is non-NULL, *lenp contains an error code (<0):
607 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
608 *		-FDT_ERR_BADMAGIC,
609 *		-FDT_ERR_BADVERSION,
610 *		-FDT_ERR_BADSTATE,
611 *		-FDT_ERR_BADSTRUCTURE,
612 *		-FDT_ERR_TRUNCATED, standard meanings
613 */
614const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
615						      int offset,
616						      int *lenp);
617
618/**
619 * fdt_get_property_namelen - find a property based on substring
620 * @fdt: pointer to the device tree blob
621 * @nodeoffset: offset of the node whose property to find
622 * @name: name of the property to find
623 * @namelen: number of characters of name to consider
624 * @lenp: pointer to an integer variable (will be overwritten) or NULL
625 *
626 * Identical to fdt_get_property(), but only examine the first namelen
627 * characters of name for matching the property name.
628 */
629#ifndef SWIG /* Not available in Python */
630const struct fdt_property *fdt_get_property_namelen(const void *fdt,
631						    int nodeoffset,
632						    const char *name,
633						    int namelen, int *lenp);
634#endif
635
636/**
637 * fdt_get_property - find a given property in a given node
638 * @fdt: pointer to the device tree blob
639 * @nodeoffset: offset of the node whose property to find
640 * @name: name of the property to find
641 * @lenp: pointer to an integer variable (will be overwritten) or NULL
642 *
643 * fdt_get_property() retrieves a pointer to the fdt_property
644 * structure within the device tree blob corresponding to the property
645 * named 'name' of the node at offset nodeoffset.  If lenp is
646 * non-NULL, the length of the property value is also returned, in the
647 * integer pointed to by lenp.
648 *
649 * returns:
650 *	pointer to the structure representing the property
651 *		if lenp is non-NULL, *lenp contains the length of the property
652 *		value (>=0)
653 *	NULL, on error
654 *		if lenp is non-NULL, *lenp contains an error code (<0):
655 *		-FDT_ERR_NOTFOUND, node does not have named property
656 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
657 *			tag
658 *		-FDT_ERR_BADMAGIC,
659 *		-FDT_ERR_BADVERSION,
660 *		-FDT_ERR_BADSTATE,
661 *		-FDT_ERR_BADSTRUCTURE,
662 *		-FDT_ERR_TRUNCATED, standard meanings
663 */
664const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
665					    const char *name, int *lenp);
666static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
667						      const char *name,
668						      int *lenp)
669{
670	return (struct fdt_property *)(uintptr_t)
671		fdt_get_property(fdt, nodeoffset, name, lenp);
672}
673
674/**
675 * fdt_getprop_by_offset - retrieve the value of a property at a given offset
676 * @fdt: pointer to the device tree blob
677 * @ffset: offset of the property to read
678 * @namep: pointer to a string variable (will be overwritten) or NULL
679 * @lenp: pointer to an integer variable (will be overwritten) or NULL
680 *
681 * fdt_getprop_by_offset() retrieves a pointer to the value of the
682 * property at structure block offset 'offset' (this will be a pointer
683 * to within the device blob itself, not a copy of the value).  If
684 * lenp is non-NULL, the length of the property value is also
685 * returned, in the integer pointed to by lenp.  If namep is non-NULL,
686 * the property's namne will also be returned in the char * pointed to
687 * by namep (this will be a pointer to within the device tree's string
688 * block, not a new copy of the name).
689 *
690 * returns:
691 *	pointer to the property's value
692 *		if lenp is non-NULL, *lenp contains the length of the property
693 *		value (>=0)
694 *		if namep is non-NULL *namep contiains a pointer to the property
695 *		name.
696 *	NULL, on error
697 *		if lenp is non-NULL, *lenp contains an error code (<0):
698 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
699 *		-FDT_ERR_BADMAGIC,
700 *		-FDT_ERR_BADVERSION,
701 *		-FDT_ERR_BADSTATE,
702 *		-FDT_ERR_BADSTRUCTURE,
703 *		-FDT_ERR_TRUNCATED, standard meanings
704 */
705#ifndef SWIG /* This function is not useful in Python */
706const void *fdt_getprop_by_offset(const void *fdt, int offset,
707				  const char **namep, int *lenp);
708#endif
709
710/**
711 * fdt_getprop_namelen - get property value based on substring
712 * @fdt: pointer to the device tree blob
713 * @nodeoffset: offset of the node whose property to find
714 * @name: name of the property to find
715 * @namelen: number of characters of name to consider
716 * @lenp: pointer to an integer variable (will be overwritten) or NULL
717 *
718 * Identical to fdt_getprop(), but only examine the first namelen
719 * characters of name for matching the property name.
720 */
721#ifndef SWIG /* Not available in Python */
722const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
723				const char *name, int namelen, int *lenp);
724static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset,
725					  const char *name, int namelen,
726					  int *lenp)
727{
728	return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name,
729						      namelen, lenp);
730}
731#endif
732
733/**
734 * fdt_getprop - retrieve the value of a given property
735 * @fdt: pointer to the device tree blob
736 * @nodeoffset: offset of the node whose property to find
737 * @name: name of the property to find
738 * @lenp: pointer to an integer variable (will be overwritten) or NULL
739 *
740 * fdt_getprop() retrieves a pointer to the value of the property
741 * named 'name' of the node at offset nodeoffset (this will be a
742 * pointer to within the device blob itself, not a copy of the value).
743 * If lenp is non-NULL, the length of the property value is also
744 * returned, in the integer pointed to by lenp.
745 *
746 * returns:
747 *	pointer to the property's value
748 *		if lenp is non-NULL, *lenp contains the length of the property
749 *		value (>=0)
750 *	NULL, on error
751 *		if lenp is non-NULL, *lenp contains an error code (<0):
752 *		-FDT_ERR_NOTFOUND, node does not have named property
753 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
754 *			tag
755 *		-FDT_ERR_BADMAGIC,
756 *		-FDT_ERR_BADVERSION,
757 *		-FDT_ERR_BADSTATE,
758 *		-FDT_ERR_BADSTRUCTURE,
759 *		-FDT_ERR_TRUNCATED, standard meanings
760 */
761const void *fdt_getprop(const void *fdt, int nodeoffset,
762			const char *name, int *lenp);
763static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
764				  const char *name, int *lenp)
765{
766	return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
767}
768
769/**
770 * fdt_get_phandle - retrieve the phandle of a given node
771 * @fdt: pointer to the device tree blob
772 * @nodeoffset: structure block offset of the node
773 *
774 * fdt_get_phandle() retrieves the phandle of the device tree node at
775 * structure block offset nodeoffset.
776 *
777 * returns:
778 *	the phandle of the node at nodeoffset, on success (!= 0, != -1)
779 *	0, if the node has no phandle, or another error occurs
780 */
781uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
782
783/**
784 * fdt_get_alias_namelen - get alias based on substring
785 * @fdt: pointer to the device tree blob
786 * @name: name of the alias th look up
787 * @namelen: number of characters of name to consider
788 *
789 * Identical to fdt_get_alias(), but only examine the first namelen
790 * characters of name for matching the alias name.
791 */
792#ifndef SWIG /* Not available in Python */
793const char *fdt_get_alias_namelen(const void *fdt,
794				  const char *name, int namelen);
795#endif
796
797/**
798 * fdt_get_alias - retrieve the path referenced by a given alias
799 * @fdt: pointer to the device tree blob
800 * @name: name of the alias th look up
801 *
802 * fdt_get_alias() retrieves the value of a given alias.  That is, the
803 * value of the property named 'name' in the node /aliases.
804 *
805 * returns:
806 *	a pointer to the expansion of the alias named 'name', if it exists
807 *	NULL, if the given alias or the /aliases node does not exist
808 */
809const char *fdt_get_alias(const void *fdt, const char *name);
810
811/**
812 * fdt_get_path - determine the full path of a node
813 * @fdt: pointer to the device tree blob
814 * @nodeoffset: offset of the node whose path to find
815 * @buf: character buffer to contain the returned path (will be overwritten)
816 * @buflen: size of the character buffer at buf
817 *
818 * fdt_get_path() computes the full path of the node at offset
819 * nodeoffset, and records that path in the buffer at buf.
820 *
821 * NOTE: This function is expensive, as it must scan the device tree
822 * structure from the start to nodeoffset.
823 *
824 * returns:
825 *	0, on success
826 *		buf contains the absolute path of the node at
827 *		nodeoffset, as a NUL-terminated string.
828 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
829 *	-FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
830 *		characters and will not fit in the given buffer.
831 *	-FDT_ERR_BADMAGIC,
832 *	-FDT_ERR_BADVERSION,
833 *	-FDT_ERR_BADSTATE,
834 *	-FDT_ERR_BADSTRUCTURE, standard meanings
835 */
836int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
837
838/**
839 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
840 * @fdt: pointer to the device tree blob
841 * @nodeoffset: offset of the node whose parent to find
842 * @supernodedepth: depth of the ancestor to find
843 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
844 *
845 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
846 * at a specific depth from the root (where the root itself has depth
847 * 0, its immediate subnodes depth 1 and so forth).  So
848 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
849 * will always return 0, the offset of the root node.  If the node at
850 * nodeoffset has depth D, then:
851 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
852 * will return nodeoffset itself.
853 *
854 * NOTE: This function is expensive, as it must scan the device tree
855 * structure from the start to nodeoffset.
856 *
857 * returns:
858 *	structure block offset of the node at node offset's ancestor
859 *		of depth supernodedepth (>=0), on success
860 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
861 *	-FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of
862 *		nodeoffset
863 *	-FDT_ERR_BADMAGIC,
864 *	-FDT_ERR_BADVERSION,
865 *	-FDT_ERR_BADSTATE,
866 *	-FDT_ERR_BADSTRUCTURE, standard meanings
867 */
868int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
869				 int supernodedepth, int *nodedepth);
870
871/**
872 * fdt_node_depth - find the depth of a given node
873 * @fdt: pointer to the device tree blob
874 * @nodeoffset: offset of the node whose parent to find
875 *
876 * fdt_node_depth() finds the depth of a given node.  The root node
877 * has depth 0, its immediate subnodes depth 1 and so forth.
878 *
879 * NOTE: This function is expensive, as it must scan the device tree
880 * structure from the start to nodeoffset.
881 *
882 * returns:
883 *	depth of the node at nodeoffset (>=0), on success
884 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
885 *	-FDT_ERR_BADMAGIC,
886 *	-FDT_ERR_BADVERSION,
887 *	-FDT_ERR_BADSTATE,
888 *	-FDT_ERR_BADSTRUCTURE, standard meanings
889 */
890int fdt_node_depth(const void *fdt, int nodeoffset);
891
892/**
893 * fdt_parent_offset - find the parent of a given node
894 * @fdt: pointer to the device tree blob
895 * @nodeoffset: offset of the node whose parent to find
896 *
897 * fdt_parent_offset() locates the parent node of a given node (that
898 * is, it finds the offset of the node which contains the node at
899 * nodeoffset as a subnode).
900 *
901 * NOTE: This function is expensive, as it must scan the device tree
902 * structure from the start to nodeoffset, *twice*.
903 *
904 * returns:
905 *	structure block offset of the parent of the node at nodeoffset
906 *		(>=0), on success
907 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
908 *	-FDT_ERR_BADMAGIC,
909 *	-FDT_ERR_BADVERSION,
910 *	-FDT_ERR_BADSTATE,
911 *	-FDT_ERR_BADSTRUCTURE, standard meanings
912 */
913int fdt_parent_offset(const void *fdt, int nodeoffset);
914
915/**
916 * fdt_node_offset_by_prop_value - find nodes with a given property value
917 * @fdt: pointer to the device tree blob
918 * @startoffset: only find nodes after this offset
919 * @propname: property name to check
920 * @propval: property value to search for
921 * @proplen: length of the value in propval
922 *
923 * fdt_node_offset_by_prop_value() returns the offset of the first
924 * node after startoffset, which has a property named propname whose
925 * value is of length proplen and has value equal to propval; or if
926 * startoffset is -1, the very first such node in the tree.
927 *
928 * To iterate through all nodes matching the criterion, the following
929 * idiom can be used:
930 *	offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
931 *					       propval, proplen);
932 *	while (offset != -FDT_ERR_NOTFOUND) {
933 *		// other code here
934 *		offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
935 *						       propval, proplen);
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_prop_value(const void *fdt, int startoffset,
954				  const char *propname,
955				  const void *propval, int proplen);
956
957/**
958 * fdt_node_offset_by_phandle - find the node with a given phandle
959 * @fdt: pointer to the device tree blob
960 * @phandle: phandle value
961 *
962 * fdt_node_offset_by_phandle() returns the offset of the node
963 * which has the given phandle value.  If there is more than one node
964 * in the tree with the given phandle (an invalid tree), results are
965 * undefined.
966 *
967 * returns:
968 *	structure block offset of the located node (>= 0), on success
969 *	-FDT_ERR_NOTFOUND, no node with that phandle exists
970 *	-FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
971 *	-FDT_ERR_BADMAGIC,
972 *	-FDT_ERR_BADVERSION,
973 *	-FDT_ERR_BADSTATE,
974 *	-FDT_ERR_BADSTRUCTURE, standard meanings
975 */
976int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
977
978/**
979 * fdt_node_check_compatible: check a node's compatible property
980 * @fdt: pointer to the device tree blob
981 * @nodeoffset: offset of a tree node
982 * @compatible: string to match against
983 *
984 *
985 * fdt_node_check_compatible() returns 0 if the given node contains a
986 * 'compatible' property with the given string as one of its elements,
987 * it returns non-zero otherwise, or on error.
988 *
989 * returns:
990 *	0, if the node has a 'compatible' property listing the given string
991 *	1, if the node has a 'compatible' property, but it does not list
992 *		the given string
993 *	-FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
994 *	-FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
995 *	-FDT_ERR_BADMAGIC,
996 *	-FDT_ERR_BADVERSION,
997 *	-FDT_ERR_BADSTATE,
998 *	-FDT_ERR_BADSTRUCTURE, standard meanings
999 */
1000int fdt_node_check_compatible(const void *fdt, int nodeoffset,
1001			      const char *compatible);
1002
1003/**
1004 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
1005 * @fdt: pointer to the device tree blob
1006 * @startoffset: only find nodes after this offset
1007 * @compatible: 'compatible' string to match against
1008 *
1009 * fdt_node_offset_by_compatible() returns the offset of the first
1010 * node after startoffset, which has a 'compatible' property which
1011 * lists the given compatible string; or if startoffset is -1, the
1012 * very first such node in the tree.
1013 *
1014 * To iterate through all nodes matching the criterion, the following
1015 * idiom can be used:
1016 *	offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
1017 *	while (offset != -FDT_ERR_NOTFOUND) {
1018 *		// other code here
1019 *		offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
1020 *	}
1021 *
1022 * Note the -1 in the first call to the function, if 0 is used here
1023 * instead, the function will never locate the root node, even if it
1024 * matches the criterion.
1025 *
1026 * returns:
1027 *	structure block offset of the located node (>= 0, >startoffset),
1028 *		 on success
1029 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
1030 *		tree after startoffset
1031 *	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1032 *	-FDT_ERR_BADMAGIC,
1033 *	-FDT_ERR_BADVERSION,
1034 *	-FDT_ERR_BADSTATE,
1035 *	-FDT_ERR_BADSTRUCTURE, standard meanings
1036 */
1037int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
1038				  const char *compatible);
1039
1040/**
1041 * fdt_stringlist_contains - check a string list property for a string
1042 * @strlist: Property containing a list of strings to check
1043 * @listlen: Length of property
1044 * @str: String to search for
1045 *
1046 * This is a utility function provided for convenience. The list contains
1047 * one or more strings, each terminated by \0, as is found in a device tree
1048 * "compatible" property.
1049 *
1050 * @return: 1 if the string is found in the list, 0 not found, or invalid list
1051 */
1052int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
1053
1054/**
1055 * fdt_stringlist_count - count the number of strings in a string list
1056 * @fdt: pointer to the device tree blob
1057 * @nodeoffset: offset of a tree node
1058 * @property: name of the property containing the string list
1059 * @return:
1060 *   the number of strings in the given property
1061 *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1062 *   -FDT_ERR_NOTFOUND if the property does not exist
1063 */
1064int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property);
1065
1066/**
1067 * fdt_stringlist_search - find a string in a string list and return its index
1068 * @fdt: pointer to the device tree blob
1069 * @nodeoffset: offset of a tree node
1070 * @property: name of the property containing the string list
1071 * @string: string to look up in the string list
1072 *
1073 * Note that it is possible for this function to succeed on property values
1074 * that are not NUL-terminated. That's because the function will stop after
1075 * finding the first occurrence of @string. This can for example happen with
1076 * small-valued cell properties, such as #address-cells, when searching for
1077 * the empty string.
1078 *
1079 * @return:
1080 *   the index of the string in the list of strings
1081 *   -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1082 *   -FDT_ERR_NOTFOUND if the property does not exist or does not contain
1083 *                     the given string
1084 */
1085int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
1086			  const char *string);
1087
1088/**
1089 * fdt_stringlist_get() - obtain the string at a given index in a string list
1090 * @fdt: pointer to the device tree blob
1091 * @nodeoffset: offset of a tree node
1092 * @property: name of the property containing the string list
1093 * @index: index of the string to return
1094 * @lenp: return location for the string length or an error code on failure
1095 *
1096 * Note that this will successfully extract strings from properties with
1097 * non-NUL-terminated values. For example on small-valued cell properties
1098 * this function will return the empty string.
1099 *
1100 * If non-NULL, the length of the string (on success) or a negative error-code
1101 * (on failure) will be stored in the integer pointer to by lenp.
1102 *
1103 * @return:
1104 *   A pointer to the string at the given index in the string list or NULL on
1105 *   failure. On success the length of the string will be stored in the memory
1106 *   location pointed to by the lenp parameter, if non-NULL. On failure one of
1107 *   the following negative error codes will be returned in the lenp parameter
1108 *   (if non-NULL):
1109 *     -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1110 *     -FDT_ERR_NOTFOUND if the property does not exist
1111 */
1112const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
1113			       const char *property, int index,
1114			       int *lenp);
1115
1116/**********************************************************************/
1117/* Read-only functions (addressing related)                           */
1118/**********************************************************************/
1119
1120/**
1121 * FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells
1122 *
1123 * This is the maximum value for #address-cells, #size-cells and
1124 * similar properties that will be processed by libfdt.  IEE1275
1125 * requires that OF implementations handle values up to 4.
1126 * Implementations may support larger values, but in practice higher
1127 * values aren't used.
1128 */
1129#define FDT_MAX_NCELLS		4
1130
1131/**
1132 * fdt_address_cells - retrieve address size for a bus represented in the tree
1133 * @fdt: pointer to the device tree blob
1134 * @nodeoffset: offset of the node to find the address size for
1135 *
1136 * When the node has a valid #address-cells property, returns its value.
1137 *
1138 * returns:
1139 *	0 <= n < FDT_MAX_NCELLS, on success
1140 *      2, if the node has no #address-cells property
1141 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1142 *		#address-cells property
1143 *	-FDT_ERR_BADMAGIC,
1144 *	-FDT_ERR_BADVERSION,
1145 *	-FDT_ERR_BADSTATE,
1146 *	-FDT_ERR_BADSTRUCTURE,
1147 *	-FDT_ERR_TRUNCATED, standard meanings
1148 */
1149int fdt_address_cells(const void *fdt, int nodeoffset);
1150
1151/**
1152 * fdt_size_cells - retrieve address range size for a bus represented in the
1153 *                  tree
1154 * @fdt: pointer to the device tree blob
1155 * @nodeoffset: offset of the node to find the address range size for
1156 *
1157 * When the node has a valid #size-cells property, returns its value.
1158 *
1159 * returns:
1160 *	0 <= n < FDT_MAX_NCELLS, on success
1161 *      2, if the node has no #size-cells property
1162 *      -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1163 *		#size-cells property
1164 *	-FDT_ERR_BADMAGIC,
1165 *	-FDT_ERR_BADVERSION,
1166 *	-FDT_ERR_BADSTATE,
1167 *	-FDT_ERR_BADSTRUCTURE,
1168 *	-FDT_ERR_TRUNCATED, standard meanings
1169 */
1170int fdt_size_cells(const void *fdt, int nodeoffset);
1171
1172
1173/**********************************************************************/
1174/* Write-in-place functions                                           */
1175/**********************************************************************/
1176
1177/**
1178 * fdt_setprop_inplace_namelen_partial - change a property's value,
1179 *                                       but not its size
1180 * @fdt: pointer to the device tree blob
1181 * @nodeoffset: offset of the node whose property to change
1182 * @name: name of the property to change
1183 * @namelen: number of characters of name to consider
1184 * @idx: index of the property to change in the array
1185 * @val: pointer to data to replace the property value with
1186 * @len: length of the property value
1187 *
1188 * Identical to fdt_setprop_inplace(), but modifies the given property
1189 * starting from the given index, and using only the first characters
1190 * of the name. It is useful when you want to manipulate only one value of
1191 * an array and you have a string that doesn't end with \0.
1192 */
1193#ifndef SWIG /* Not available in Python */
1194int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
1195					const char *name, int namelen,
1196					uint32_t idx, const void *val,
1197					int len);
1198#endif
1199
1200/**
1201 * fdt_setprop_inplace - change a property's value, but not its size
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: pointer to data to replace the property value with
1206 * @len: length of the property value
1207 *
1208 * fdt_setprop_inplace() replaces the value of a given property with
1209 * the data in val, of length len.  This function cannot change the
1210 * size of a property, and so will only work if len is equal to the
1211 * current length of the property.
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 len is not equal to the property's current length
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 */
1228#ifndef SWIG /* Not available in Python */
1229int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
1230			const void *val, int len);
1231#endif
1232
1233/**
1234 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
1235 * @fdt: pointer to the device tree blob
1236 * @nodeoffset: offset of the node whose property to change
1237 * @name: name of the property to change
1238 * @val: 32-bit integer value to replace the property with
1239 *
1240 * fdt_setprop_inplace_u32() replaces the value of a given property
1241 * with the 32-bit integer value in val, converting val to big-endian
1242 * if necessary.  This function cannot change the size of a property,
1243 * and so will only work if the property already exists and has length
1244 * 4.
1245 *
1246 * This function will alter only the bytes in the blob which contain
1247 * the given property value, and will not alter or move any other part
1248 * of the tree.
1249 *
1250 * returns:
1251 *	0, on success
1252 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 4
1253 *	-FDT_ERR_NOTFOUND, node does not have the named property
1254 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1255 *	-FDT_ERR_BADMAGIC,
1256 *	-FDT_ERR_BADVERSION,
1257 *	-FDT_ERR_BADSTATE,
1258 *	-FDT_ERR_BADSTRUCTURE,
1259 *	-FDT_ERR_TRUNCATED, standard meanings
1260 */
1261static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
1262					  const char *name, uint32_t val)
1263{
1264	fdt32_t tmp = cpu_to_fdt32(val);
1265	return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1266}
1267
1268/**
1269 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
1270 * @fdt: pointer to the device tree blob
1271 * @nodeoffset: offset of the node whose property to change
1272 * @name: name of the property to change
1273 * @val: 64-bit integer value to replace the property with
1274 *
1275 * fdt_setprop_inplace_u64() replaces the value of a given property
1276 * with the 64-bit integer value in val, converting val to big-endian
1277 * if necessary.  This function cannot change the size of a property,
1278 * and so will only work if the property already exists and has length
1279 * 8.
1280 *
1281 * This function will alter only the bytes in the blob which contain
1282 * the given property value, and will not alter or move any other part
1283 * of the tree.
1284 *
1285 * returns:
1286 *	0, on success
1287 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 8
1288 *	-FDT_ERR_NOTFOUND, node does not have the named property
1289 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1290 *	-FDT_ERR_BADMAGIC,
1291 *	-FDT_ERR_BADVERSION,
1292 *	-FDT_ERR_BADSTATE,
1293 *	-FDT_ERR_BADSTRUCTURE,
1294 *	-FDT_ERR_TRUNCATED, standard meanings
1295 */
1296static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
1297					  const char *name, uint64_t val)
1298{
1299	fdt64_t tmp = cpu_to_fdt64(val);
1300	return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1301}
1302
1303/**
1304 * fdt_setprop_inplace_cell - change the value of a single-cell property
1305 *
1306 * This is an alternative name for fdt_setprop_inplace_u32()
1307 */
1308static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
1309					   const char *name, uint32_t val)
1310{
1311	return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
1312}
1313
1314/**
1315 * fdt_nop_property - replace a property with nop tags
1316 * @fdt: pointer to the device tree blob
1317 * @nodeoffset: offset of the node whose property to nop
1318 * @name: name of the property to nop
1319 *
1320 * fdt_nop_property() will replace a given property's representation
1321 * in the blob with FDT_NOP tags, effectively removing it from the
1322 * tree.
1323 *
1324 * This function will alter only the bytes in the blob which contain
1325 * the property, and will not alter or move any other part of the
1326 * tree.
1327 *
1328 * returns:
1329 *	0, on success
1330 *	-FDT_ERR_NOTFOUND, node does not have the named property
1331 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1332 *	-FDT_ERR_BADMAGIC,
1333 *	-FDT_ERR_BADVERSION,
1334 *	-FDT_ERR_BADSTATE,
1335 *	-FDT_ERR_BADSTRUCTURE,
1336 *	-FDT_ERR_TRUNCATED, standard meanings
1337 */
1338int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
1339
1340/**
1341 * fdt_nop_node - replace a node (subtree) with nop tags
1342 * @fdt: pointer to the device tree blob
1343 * @nodeoffset: offset of the node to nop
1344 *
1345 * fdt_nop_node() will replace a given node's representation in the
1346 * blob, including all its subnodes, if any, with FDT_NOP tags,
1347 * effectively removing it from the tree.
1348 *
1349 * This function will alter only the bytes in the blob which contain
1350 * the node and its properties and subnodes, and will not alter or
1351 * move any other part of the tree.
1352 *
1353 * returns:
1354 *	0, on success
1355 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1356 *	-FDT_ERR_BADMAGIC,
1357 *	-FDT_ERR_BADVERSION,
1358 *	-FDT_ERR_BADSTATE,
1359 *	-FDT_ERR_BADSTRUCTURE,
1360 *	-FDT_ERR_TRUNCATED, standard meanings
1361 */
1362int fdt_nop_node(void *fdt, int nodeoffset);
1363
1364/**********************************************************************/
1365/* Sequential write functions                                         */
1366/**********************************************************************/
1367
1368int fdt_create(void *buf, int bufsize);
1369int fdt_resize(void *fdt, void *buf, int bufsize);
1370int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
1371int fdt_finish_reservemap(void *fdt);
1372int fdt_begin_node(void *fdt, const char *name);
1373int fdt_property(void *fdt, const char *name, const void *val, int len);
1374static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
1375{
1376	fdt32_t tmp = cpu_to_fdt32(val);
1377	return fdt_property(fdt, name, &tmp, sizeof(tmp));
1378}
1379static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
1380{
1381	fdt64_t tmp = cpu_to_fdt64(val);
1382	return fdt_property(fdt, name, &tmp, sizeof(tmp));
1383}
1384
1385#ifndef SWIG /* Not available in Python */
1386static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
1387{
1388	return fdt_property_u32(fdt, name, val);
1389}
1390#endif
1391
1392/**
1393 * fdt_property_placeholder - add a new property and return a ptr to its value
1394 *
1395 * @fdt: pointer to the device tree blob
1396 * @name: name of property to add
1397 * @len: length of property value in bytes
1398 * @valp: returns a pointer to where where the value should be placed
1399 *
1400 * returns:
1401 *	0, on success
1402 *	-FDT_ERR_BADMAGIC,
1403 *	-FDT_ERR_NOSPACE, standard meanings
1404 */
1405int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp);
1406
1407#define fdt_property_string(fdt, name, str) \
1408	fdt_property(fdt, name, str, strlen(str)+1)
1409int fdt_end_node(void *fdt);
1410int fdt_finish(void *fdt);
1411
1412/**********************************************************************/
1413/* Read-write functions                                               */
1414/**********************************************************************/
1415
1416int fdt_create_empty_tree(void *buf, int bufsize);
1417int fdt_open_into(const void *fdt, void *buf, int bufsize);
1418int fdt_pack(void *fdt);
1419
1420/**
1421 * fdt_add_mem_rsv - add one memory reserve map entry
1422 * @fdt: pointer to the device tree blob
1423 * @address, @size: 64-bit values (native endian)
1424 *
1425 * Adds a reserve map entry to the given blob reserving a region at
1426 * address address of length size.
1427 *
1428 * This function will insert data into the reserve map and will
1429 * therefore change the indexes of some entries in the table.
1430 *
1431 * returns:
1432 *	0, on success
1433 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1434 *		contain the new reservation entry
1435 *	-FDT_ERR_BADMAGIC,
1436 *	-FDT_ERR_BADVERSION,
1437 *	-FDT_ERR_BADSTATE,
1438 *	-FDT_ERR_BADSTRUCTURE,
1439 *	-FDT_ERR_BADLAYOUT,
1440 *	-FDT_ERR_TRUNCATED, standard meanings
1441 */
1442int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
1443
1444/**
1445 * fdt_del_mem_rsv - remove a memory reserve map entry
1446 * @fdt: pointer to the device tree blob
1447 * @n: entry to remove
1448 *
1449 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
1450 * the blob.
1451 *
1452 * This function will delete data from the reservation table and will
1453 * therefore change the indexes of some entries in the table.
1454 *
1455 * returns:
1456 *	0, on success
1457 *	-FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
1458 *		are less than n+1 reserve map entries)
1459 *	-FDT_ERR_BADMAGIC,
1460 *	-FDT_ERR_BADVERSION,
1461 *	-FDT_ERR_BADSTATE,
1462 *	-FDT_ERR_BADSTRUCTURE,
1463 *	-FDT_ERR_BADLAYOUT,
1464 *	-FDT_ERR_TRUNCATED, standard meanings
1465 */
1466int fdt_del_mem_rsv(void *fdt, int n);
1467
1468/**
1469 * fdt_set_name - change the name of a given node
1470 * @fdt: pointer to the device tree blob
1471 * @nodeoffset: structure block offset of a node
1472 * @name: name to give the node
1473 *
1474 * fdt_set_name() replaces the name (including unit address, if any)
1475 * of the given node with the given string.  NOTE: this function can't
1476 * efficiently check if the new name is unique amongst the given
1477 * node's siblings; results are undefined if this function is invoked
1478 * with a name equal to one of the given node's siblings.
1479 *
1480 * This function may insert or delete data from the blob, and will
1481 * therefore change the offsets of some existing nodes.
1482 *
1483 * returns:
1484 *	0, on success
1485 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob
1486 *		to contain the new name
1487 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1488 *	-FDT_ERR_BADMAGIC,
1489 *	-FDT_ERR_BADVERSION,
1490 *	-FDT_ERR_BADSTATE, standard meanings
1491 */
1492int fdt_set_name(void *fdt, int nodeoffset, const char *name);
1493
1494/**
1495 * fdt_setprop - create or change a property
1496 * @fdt: pointer to the device tree blob
1497 * @nodeoffset: offset of the node whose property to change
1498 * @name: name of the property to change
1499 * @val: pointer to data to set the property value to
1500 * @len: length of the property value
1501 *
1502 * fdt_setprop() sets the value of the named property in the given
1503 * node to the given value and length, creating the property if it
1504 * does not already exist.
1505 *
1506 * This function may insert or delete data from the blob, and will
1507 * therefore change the offsets of some existing nodes.
1508 *
1509 * returns:
1510 *	0, on success
1511 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1512 *		contain the new property value
1513 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1514 *	-FDT_ERR_BADLAYOUT,
1515 *	-FDT_ERR_BADMAGIC,
1516 *	-FDT_ERR_BADVERSION,
1517 *	-FDT_ERR_BADSTATE,
1518 *	-FDT_ERR_BADSTRUCTURE,
1519 *	-FDT_ERR_BADLAYOUT,
1520 *	-FDT_ERR_TRUNCATED, standard meanings
1521 */
1522int fdt_setprop(void *fdt, int nodeoffset, const char *name,
1523		const void *val, int len);
1524
1525/**
1526 * fdt_setprop_placeholder - allocate space for a property
1527 * @fdt: pointer to the device tree blob
1528 * @nodeoffset: offset of the node whose property to change
1529 * @name: name of the property to change
1530 * @len: length of the property value
1531 * @prop_data: return pointer to property data
1532 *
1533 * fdt_setprop_placeholer() allocates the named property in the given node.
1534 * If the property exists it is resized. In either case a pointer to the
1535 * property data is returned.
1536 *
1537 * This function may insert or delete data from the blob, and will
1538 * therefore change the offsets of some existing nodes.
1539 *
1540 * returns:
1541 *	0, on success
1542 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1543 *		contain the new property value
1544 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1545 *	-FDT_ERR_BADLAYOUT,
1546 *	-FDT_ERR_BADMAGIC,
1547 *	-FDT_ERR_BADVERSION,
1548 *	-FDT_ERR_BADSTATE,
1549 *	-FDT_ERR_BADSTRUCTURE,
1550 *	-FDT_ERR_BADLAYOUT,
1551 *	-FDT_ERR_TRUNCATED, standard meanings
1552 */
1553int fdt_setprop_placeholder(void *fdt, int nodeoffset, const char *name,
1554			    int len, void **prop_data);
1555
1556/**
1557 * fdt_setprop_u32 - set a property to a 32-bit integer
1558 * @fdt: pointer to the device tree blob
1559 * @nodeoffset: offset of the node whose property to change
1560 * @name: name of the property to change
1561 * @val: 32-bit integer value for the property (native endian)
1562 *
1563 * fdt_setprop_u32() sets the value of the named property in the given
1564 * node to the given 32-bit integer value (converting to big-endian if
1565 * necessary), or creates a new property with that value if it does
1566 * not already exist.
1567 *
1568 * This function may insert or delete data from the blob, and will
1569 * therefore change the offsets of some existing nodes.
1570 *
1571 * returns:
1572 *	0, on success
1573 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1574 *		contain the new property value
1575 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1576 *	-FDT_ERR_BADLAYOUT,
1577 *	-FDT_ERR_BADMAGIC,
1578 *	-FDT_ERR_BADVERSION,
1579 *	-FDT_ERR_BADSTATE,
1580 *	-FDT_ERR_BADSTRUCTURE,
1581 *	-FDT_ERR_BADLAYOUT,
1582 *	-FDT_ERR_TRUNCATED, standard meanings
1583 */
1584static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
1585				  uint32_t val)
1586{
1587	fdt32_t tmp = cpu_to_fdt32(val);
1588	return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1589}
1590
1591/**
1592 * fdt_setprop_u64 - set a property to a 64-bit integer
1593 * @fdt: pointer to the device tree blob
1594 * @nodeoffset: offset of the node whose property to change
1595 * @name: name of the property to change
1596 * @val: 64-bit integer value for the property (native endian)
1597 *
1598 * fdt_setprop_u64() sets the value of the named property in the given
1599 * node to the given 64-bit integer value (converting to big-endian if
1600 * necessary), or creates a new property with that value if it does
1601 * not already exist.
1602 *
1603 * This function may insert or delete data from the blob, and will
1604 * therefore change the offsets of some existing nodes.
1605 *
1606 * returns:
1607 *	0, on success
1608 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1609 *		contain the new property value
1610 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1611 *	-FDT_ERR_BADLAYOUT,
1612 *	-FDT_ERR_BADMAGIC,
1613 *	-FDT_ERR_BADVERSION,
1614 *	-FDT_ERR_BADSTATE,
1615 *	-FDT_ERR_BADSTRUCTURE,
1616 *	-FDT_ERR_BADLAYOUT,
1617 *	-FDT_ERR_TRUNCATED, standard meanings
1618 */
1619static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
1620				  uint64_t val)
1621{
1622	fdt64_t tmp = cpu_to_fdt64(val);
1623	return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1624}
1625
1626/**
1627 * fdt_setprop_cell - set a property to a single cell value
1628 *
1629 * This is an alternative name for fdt_setprop_u32()
1630 */
1631static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
1632				   uint32_t val)
1633{
1634	return fdt_setprop_u32(fdt, nodeoffset, name, val);
1635}
1636
1637/**
1638 * fdt_setprop_string - set a property to a string value
1639 * @fdt: pointer to the device tree blob
1640 * @nodeoffset: offset of the node whose property to change
1641 * @name: name of the property to change
1642 * @str: string value for the property
1643 *
1644 * fdt_setprop_string() sets the value of the named property in the
1645 * given node to the given string value (using the length of the
1646 * string to determine the new length of the property), or creates a
1647 * new property with that value if it does not already exist.
1648 *
1649 * This function may insert or delete data from the blob, and will
1650 * therefore change the offsets of some existing nodes.
1651 *
1652 * returns:
1653 *	0, on success
1654 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1655 *		contain the new property value
1656 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1657 *	-FDT_ERR_BADLAYOUT,
1658 *	-FDT_ERR_BADMAGIC,
1659 *	-FDT_ERR_BADVERSION,
1660 *	-FDT_ERR_BADSTATE,
1661 *	-FDT_ERR_BADSTRUCTURE,
1662 *	-FDT_ERR_BADLAYOUT,
1663 *	-FDT_ERR_TRUNCATED, standard meanings
1664 */
1665#define fdt_setprop_string(fdt, nodeoffset, name, str) \
1666	fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1667
1668
1669/**
1670 * fdt_setprop_empty - set a property to an empty value
1671 * @fdt: pointer to the device tree blob
1672 * @nodeoffset: offset of the node whose property to change
1673 * @name: name of the property to change
1674 *
1675 * fdt_setprop_empty() sets the value of the named property in the
1676 * given node to an empty (zero length) value, or creates a new empty
1677 * property if it does not already exist.
1678 *
1679 * This function may insert or delete data from the blob, and will
1680 * therefore change the offsets of some existing nodes.
1681 *
1682 * returns:
1683 *	0, on success
1684 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1685 *		contain the new property value
1686 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1687 *	-FDT_ERR_BADLAYOUT,
1688 *	-FDT_ERR_BADMAGIC,
1689 *	-FDT_ERR_BADVERSION,
1690 *	-FDT_ERR_BADSTATE,
1691 *	-FDT_ERR_BADSTRUCTURE,
1692 *	-FDT_ERR_BADLAYOUT,
1693 *	-FDT_ERR_TRUNCATED, standard meanings
1694 */
1695#define fdt_setprop_empty(fdt, nodeoffset, name) \
1696	fdt_setprop((fdt), (nodeoffset), (name), NULL, 0)
1697
1698/**
1699 * fdt_appendprop - append to or create a property
1700 * @fdt: pointer to the device tree blob
1701 * @nodeoffset: offset of the node whose property to change
1702 * @name: name of the property to append to
1703 * @val: pointer to data to append to the property value
1704 * @len: length of the data to append to the property value
1705 *
1706 * fdt_appendprop() appends the value to the named property in the
1707 * given node, creating the property if it does not already exist.
1708 *
1709 * This function may insert data into the blob, and will therefore
1710 * change the offsets of some existing nodes.
1711 *
1712 * returns:
1713 *	0, on success
1714 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1715 *		contain the new property value
1716 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1717 *	-FDT_ERR_BADLAYOUT,
1718 *	-FDT_ERR_BADMAGIC,
1719 *	-FDT_ERR_BADVERSION,
1720 *	-FDT_ERR_BADSTATE,
1721 *	-FDT_ERR_BADSTRUCTURE,
1722 *	-FDT_ERR_BADLAYOUT,
1723 *	-FDT_ERR_TRUNCATED, standard meanings
1724 */
1725int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
1726		   const void *val, int len);
1727
1728/**
1729 * fdt_appendprop_u32 - append a 32-bit integer value to a property
1730 * @fdt: pointer to the device tree blob
1731 * @nodeoffset: offset of the node whose property to change
1732 * @name: name of the property to change
1733 * @val: 32-bit integer value to append to the property (native endian)
1734 *
1735 * fdt_appendprop_u32() appends the given 32-bit integer value
1736 * (converting to big-endian if necessary) to the value of the named
1737 * property in the given node, or creates a new property with that
1738 * value if it does not already exist.
1739 *
1740 * This function may insert data into the blob, and will therefore
1741 * change the offsets of some existing nodes.
1742 *
1743 * returns:
1744 *	0, on success
1745 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1746 *		contain the new property value
1747 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1748 *	-FDT_ERR_BADLAYOUT,
1749 *	-FDT_ERR_BADMAGIC,
1750 *	-FDT_ERR_BADVERSION,
1751 *	-FDT_ERR_BADSTATE,
1752 *	-FDT_ERR_BADSTRUCTURE,
1753 *	-FDT_ERR_BADLAYOUT,
1754 *	-FDT_ERR_TRUNCATED, standard meanings
1755 */
1756static inline int fdt_appendprop_u32(void *fdt, int nodeoffset,
1757				     const char *name, uint32_t val)
1758{
1759	fdt32_t tmp = cpu_to_fdt32(val);
1760	return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1761}
1762
1763/**
1764 * fdt_appendprop_u64 - append a 64-bit integer value to a property
1765 * @fdt: pointer to the device tree blob
1766 * @nodeoffset: offset of the node whose property to change
1767 * @name: name of the property to change
1768 * @val: 64-bit integer value to append to the property (native endian)
1769 *
1770 * fdt_appendprop_u64() appends the given 64-bit integer value
1771 * (converting to big-endian if necessary) to the value of the named
1772 * property in the given node, or creates a new property with that
1773 * value if it does not already exist.
1774 *
1775 * This function may insert data into the blob, and will therefore
1776 * change the offsets of some existing nodes.
1777 *
1778 * returns:
1779 *	0, on success
1780 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1781 *		contain the new property value
1782 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1783 *	-FDT_ERR_BADLAYOUT,
1784 *	-FDT_ERR_BADMAGIC,
1785 *	-FDT_ERR_BADVERSION,
1786 *	-FDT_ERR_BADSTATE,
1787 *	-FDT_ERR_BADSTRUCTURE,
1788 *	-FDT_ERR_BADLAYOUT,
1789 *	-FDT_ERR_TRUNCATED, standard meanings
1790 */
1791static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
1792				     const char *name, uint64_t val)
1793{
1794	fdt64_t tmp = cpu_to_fdt64(val);
1795	return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1796}
1797
1798/**
1799 * fdt_appendprop_cell - append a single cell value to a property
1800 *
1801 * This is an alternative name for fdt_appendprop_u32()
1802 */
1803static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
1804				      const char *name, uint32_t val)
1805{
1806	return fdt_appendprop_u32(fdt, nodeoffset, name, val);
1807}
1808
1809/**
1810 * fdt_appendprop_string - append a string to a property
1811 * @fdt: pointer to the device tree blob
1812 * @nodeoffset: offset of the node whose property to change
1813 * @name: name of the property to change
1814 * @str: string value to append to the property
1815 *
1816 * fdt_appendprop_string() appends the given string to the value of
1817 * the named property in the given node, or creates a new property
1818 * with that value if it does not already exist.
1819 *
1820 * This function may insert data into the blob, and will therefore
1821 * change the offsets of some existing nodes.
1822 *
1823 * returns:
1824 *	0, on success
1825 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1826 *		contain the new property value
1827 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1828 *	-FDT_ERR_BADLAYOUT,
1829 *	-FDT_ERR_BADMAGIC,
1830 *	-FDT_ERR_BADVERSION,
1831 *	-FDT_ERR_BADSTATE,
1832 *	-FDT_ERR_BADSTRUCTURE,
1833 *	-FDT_ERR_BADLAYOUT,
1834 *	-FDT_ERR_TRUNCATED, standard meanings
1835 */
1836#define fdt_appendprop_string(fdt, nodeoffset, name, str) \
1837	fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1838
1839/**
1840 * fdt_delprop - delete a property
1841 * @fdt: pointer to the device tree blob
1842 * @nodeoffset: offset of the node whose property to nop
1843 * @name: name of the property to nop
1844 *
1845 * fdt_del_property() will delete the given property.
1846 *
1847 * This function will delete data from the blob, and will therefore
1848 * change the offsets of some existing nodes.
1849 *
1850 * returns:
1851 *	0, on success
1852 *	-FDT_ERR_NOTFOUND, node does not have the named property
1853 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1854 *	-FDT_ERR_BADLAYOUT,
1855 *	-FDT_ERR_BADMAGIC,
1856 *	-FDT_ERR_BADVERSION,
1857 *	-FDT_ERR_BADSTATE,
1858 *	-FDT_ERR_BADSTRUCTURE,
1859 *	-FDT_ERR_TRUNCATED, standard meanings
1860 */
1861int fdt_delprop(void *fdt, int nodeoffset, const char *name);
1862
1863/**
1864 * fdt_add_subnode_namelen - creates a new node based on substring
1865 * @fdt: pointer to the device tree blob
1866 * @parentoffset: structure block offset of a node
1867 * @name: name of the subnode to locate
1868 * @namelen: number of characters of name to consider
1869 *
1870 * Identical to fdt_add_subnode(), but use only the first namelen
1871 * characters of name as the name of the new node.  This is useful for
1872 * creating subnodes based on a portion of a larger string, such as a
1873 * full path.
1874 */
1875#ifndef SWIG /* Not available in Python */
1876int fdt_add_subnode_namelen(void *fdt, int parentoffset,
1877			    const char *name, int namelen);
1878#endif
1879
1880/**
1881 * fdt_add_subnode - creates a new node
1882 * @fdt: pointer to the device tree blob
1883 * @parentoffset: structure block offset of a node
1884 * @name: name of the subnode to locate
1885 *
1886 * fdt_add_subnode() creates a new node as a subnode of the node at
1887 * structure block offset parentoffset, with the given name (which
1888 * should include the unit address, if any).
1889 *
1890 * This function will insert data into the blob, and will therefore
1891 * change the offsets of some existing nodes.
1892
1893 * returns:
1894 *	structure block offset of the created nodeequested subnode (>=0), on
1895 *		success
1896 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
1897 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
1898 *		tag
1899 *	-FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
1900 *		the given name
1901 *	-FDT_ERR_NOSPACE, if there is insufficient free space in the
1902 *		blob to contain the new node
1903 *	-FDT_ERR_NOSPACE
1904 *	-FDT_ERR_BADLAYOUT
1905 *      -FDT_ERR_BADMAGIC,
1906 *	-FDT_ERR_BADVERSION,
1907 *	-FDT_ERR_BADSTATE,
1908 *	-FDT_ERR_BADSTRUCTURE,
1909 *	-FDT_ERR_TRUNCATED, standard meanings.
1910 */
1911int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
1912
1913/**
1914 * fdt_del_node - delete a node (subtree)
1915 * @fdt: pointer to the device tree blob
1916 * @nodeoffset: offset of the node to nop
1917 *
1918 * fdt_del_node() will remove the given node, including all its
1919 * subnodes if any, from the blob.
1920 *
1921 * This function will delete data from the blob, and will therefore
1922 * change the offsets of some existing nodes.
1923 *
1924 * returns:
1925 *	0, on success
1926 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1927 *	-FDT_ERR_BADLAYOUT,
1928 *	-FDT_ERR_BADMAGIC,
1929 *	-FDT_ERR_BADVERSION,
1930 *	-FDT_ERR_BADSTATE,
1931 *	-FDT_ERR_BADSTRUCTURE,
1932 *	-FDT_ERR_TRUNCATED, standard meanings
1933 */
1934int fdt_del_node(void *fdt, int nodeoffset);
1935
1936/**
1937 * fdt_overlay_apply - Applies a DT overlay on a base DT
1938 * @fdt: pointer to the base device tree blob
1939 * @fdto: pointer to the device tree overlay blob
1940 *
1941 * fdt_overlay_apply() will apply the given device tree overlay on the
1942 * given base device tree.
1943 *
1944 * Expect the base device tree to be modified, even if the function
1945 * returns an error.
1946 *
1947 * returns:
1948 *	0, on success
1949 *	-FDT_ERR_NOSPACE, there's not enough space in the base device tree
1950 *	-FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
1951 *		properties in the base DT
1952 *	-FDT_ERR_BADPHANDLE,
1953 *	-FDT_ERR_BADOVERLAY,
1954 *	-FDT_ERR_NOPHANDLES,
1955 *	-FDT_ERR_INTERNAL,
1956 *	-FDT_ERR_BADLAYOUT,
1957 *	-FDT_ERR_BADMAGIC,
1958 *	-FDT_ERR_BADOFFSET,
1959 *	-FDT_ERR_BADPATH,
1960 *	-FDT_ERR_BADVERSION,
1961 *	-FDT_ERR_BADSTRUCTURE,
1962 *	-FDT_ERR_BADSTATE,
1963 *	-FDT_ERR_TRUNCATED, standard meanings
1964 */
1965int fdt_overlay_apply(void *fdt, void *fdto);
1966
1967/**********************************************************************/
1968/* Debugging / informational functions                                */
1969/**********************************************************************/
1970
1971const char *fdt_strerror(int errval);
1972
1973#endif /* LIBFDT_H */
1974