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1#ifndef _LIBFDT_H
2#define _LIBFDT_H
3/*
4 * libfdt - Flat Device Tree manipulation
5 * Copyright (C) 2006 David Gibson, IBM Corporation.
6 *
7 * libfdt is dual licensed: you can use it either under the terms of
8 * the GPL, or the BSD license, at your option.
9 *
10 * a) This library is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License as
12 * published by the Free Software Foundation; either version 2 of the
13 * License, or (at your option) any later version.
14 *
15 * This library is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public
21 * License along with this library; if not, write to the Free
22 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
23 * MA 02110-1301 USA
24 *
25 * Alternatively,
26 *
27 * b) Redistribution and use in source and binary forms, with or
28 * without modification, are permitted provided that the following
29 * conditions are met:
30 *
31 * 1. Redistributions of source code must retain the above
32 * copyright notice, this list of conditions and the following
33 * disclaimer.
34 * 2. Redistributions in binary form must reproduce the above
35 * copyright notice, this list of conditions and the following
36 * disclaimer in the documentation and/or other materials
37 * provided with the distribution.
38 *
39 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
40 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
41 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
42 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
43 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
44 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
49 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
50 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
51 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
52 */
53
54#include <libfdt_env.h>
55#include <fdt.h>
56
57#define FDT_FIRST_SUPPORTED_VERSION 0x10
58#define FDT_LAST_SUPPORTED_VERSION 0x11
59
60/* Error codes: informative error codes */
61#define FDT_ERR_NOTFOUND 1
62 /* FDT_ERR_NOTFOUND: The requested node or property does not exist */
63#define FDT_ERR_EXISTS 2
64 /* FDT_ERR_EXISTS: Attemped to create a node or property which
65 * already exists */
66#define FDT_ERR_NOSPACE 3
67 /* FDT_ERR_NOSPACE: Operation needed to expand the device
68 * tree, but its buffer did not have sufficient space to
69 * contain the expanded tree. Use fdt_open_into() to move the
70 * device tree to a buffer with more space. */
71
72/* Error codes: codes for bad parameters */
73#define FDT_ERR_BADOFFSET 4
74 /* FDT_ERR_BADOFFSET: Function was passed a structure block
75 * offset which is out-of-bounds, or which points to an
76 * unsuitable part of the structure for the operation. */
77#define FDT_ERR_BADPATH 5
78 /* FDT_ERR_BADPATH: Function was passed a badly formatted path
79 * (e.g. missing a leading / for a function which requires an
80 * absolute path) */
81#define FDT_ERR_BADPHANDLE 6
82 /* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle
83 * value. phandle values of 0 and -1 are not permitted. */
84#define FDT_ERR_BADSTATE 7
85 /* FDT_ERR_BADSTATE: Function was passed an incomplete device
86 * tree created by the sequential-write functions, which is
87 * not sufficiently complete for the requested operation. */
88
89/* Error codes: codes for bad device tree blobs */
90#define FDT_ERR_TRUNCATED 8
91 /* FDT_ERR_TRUNCATED: Structure block of the given device tree
92 * ends without an FDT_END tag. */
93#define FDT_ERR_BADMAGIC 9
94 /* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
95 * device tree at all - it is missing the flattened device
96 * tree magic number. */
97#define FDT_ERR_BADVERSION 10
98 /* FDT_ERR_BADVERSION: Given device tree has a version which
99 * can't be handled by the requested operation. For
100 * read-write functions, this may mean that fdt_open_into() is
101 * required to convert the tree to the expected version. */
102#define FDT_ERR_BADSTRUCTURE 11
103 /* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt
104 * structure block or other serious error (e.g. misnested
105 * nodes, or subnodes preceding properties). */
106#define FDT_ERR_BADLAYOUT 12
107 /* FDT_ERR_BADLAYOUT: For read-write functions, the given
108 * device tree has it's sub-blocks in an order that the
109 * function can't handle (memory reserve map, then structure,
110 * then strings). Use fdt_open_into() to reorganize the tree
111 * into a form suitable for the read-write operations. */
112
113/* "Can't happen" error indicating a bug in libfdt */
114#define FDT_ERR_INTERNAL 13
115 /* FDT_ERR_INTERNAL: libfdt has failed an internal assertion.
116 * Should never be returned, if it is, it indicates a bug in
117 * libfdt itself. */
118
119#define FDT_ERR_MAX 13
120
121/**********************************************************************/
122/* Low-level functions (you probably don't need these) */
123/**********************************************************************/
124
125const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen);
126static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
127{
128 return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
129}
130
131uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
132
133/**********************************************************************/
134/* Traversal functions */
135/**********************************************************************/
136
137int fdt_next_node(const void *fdt, int offset, int *depth);
138
139/**********************************************************************/
140/* General functions */
141/**********************************************************************/
142
143#define fdt_get_header(fdt, field) \
144 (fdt32_to_cpu(((const struct fdt_header *)(fdt))->field))
145#define fdt_magic(fdt) (fdt_get_header(fdt, magic))
146#define fdt_totalsize(fdt) (fdt_get_header(fdt, totalsize))
147#define fdt_off_dt_struct(fdt) (fdt_get_header(fdt, off_dt_struct))
148#define fdt_off_dt_strings(fdt) (fdt_get_header(fdt, off_dt_strings))
149#define fdt_off_mem_rsvmap(fdt) (fdt_get_header(fdt, off_mem_rsvmap))
150#define fdt_version(fdt) (fdt_get_header(fdt, version))
151#define fdt_last_comp_version(fdt) (fdt_get_header(fdt, last_comp_version))
152#define fdt_boot_cpuid_phys(fdt) (fdt_get_header(fdt, boot_cpuid_phys))
153#define fdt_size_dt_strings(fdt) (fdt_get_header(fdt, size_dt_strings))
154#define fdt_size_dt_struct(fdt) (fdt_get_header(fdt, size_dt_struct))
155
156#define __fdt_set_hdr(name) \
157 static inline void fdt_set_##name(void *fdt, uint32_t val) \
158 { \
159 struct fdt_header *fdth = (struct fdt_header*)fdt; \
160 fdth->name = cpu_to_fdt32(val); \
161 }
162__fdt_set_hdr(magic);
163__fdt_set_hdr(totalsize);
164__fdt_set_hdr(off_dt_struct);
165__fdt_set_hdr(off_dt_strings);
166__fdt_set_hdr(off_mem_rsvmap);
167__fdt_set_hdr(version);
168__fdt_set_hdr(last_comp_version);
169__fdt_set_hdr(boot_cpuid_phys);
170__fdt_set_hdr(size_dt_strings);
171__fdt_set_hdr(size_dt_struct);
172#undef __fdt_set_hdr
173
174/**
175 * fdt_check_header - sanity check a device tree or possible device tree
176 * @fdt: pointer to data which might be a flattened device tree
177 *
178 * fdt_check_header() checks that the given buffer contains what
179 * appears to be a flattened device tree with sane information in its
180 * header.
181 *
182 * returns:
183 * 0, if the buffer appears to contain a valid device tree
184 * -FDT_ERR_BADMAGIC,
185 * -FDT_ERR_BADVERSION,
186 * -FDT_ERR_BADSTATE, standard meanings, as above
187 */
188int fdt_check_header(const void *fdt);
189
190/**
191 * fdt_move - move a device tree around in memory
192 * @fdt: pointer to the device tree to move
193 * @buf: pointer to memory where the device is to be moved
194 * @bufsize: size of the memory space at buf
195 *
196 * fdt_move() relocates, if possible, the device tree blob located at
197 * fdt to the buffer at buf of size bufsize. The buffer may overlap
198 * with the existing device tree blob at fdt. Therefore,
199 * fdt_move(fdt, fdt, fdt_totalsize(fdt))
200 * should always succeed.
201 *
202 * returns:
203 * 0, on success
204 * -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
205 * -FDT_ERR_BADMAGIC,
206 * -FDT_ERR_BADVERSION,
207 * -FDT_ERR_BADSTATE, standard meanings
208 */
209int fdt_move(const void *fdt, void *buf, int bufsize);
210
211/**********************************************************************/
212/* Read-only functions */
213/**********************************************************************/
214
215/**
216 * fdt_string - retrieve a string from the strings block of a device tree
217 * @fdt: pointer to the device tree blob
218 * @stroffset: offset of the string within the strings block (native endian)
219 *
220 * fdt_string() retrieves a pointer to a single string from the
221 * strings block of the device tree blob at fdt.
222 *
223 * returns:
224 * a pointer to the string, on success
225 * NULL, if stroffset is out of bounds
226 */
227const char *fdt_string(const void *fdt, int stroffset);
228
229/**
230 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
231 * @fdt: pointer to the device tree blob
232 *
233 * Returns the number of entries in the device tree blob's memory
234 * reservation map. This does not include the terminating 0,0 entry
235 * or any other (0,0) entries reserved for expansion.
236 *
237 * returns:
238 * the number of entries
239 */
240int fdt_num_mem_rsv(const void *fdt);
241
242/**
243 * fdt_get_mem_rsv - retrieve one memory reserve map entry
244 * @fdt: pointer to the device tree blob
245 * @address, @size: pointers to 64-bit variables
246 *
247 * On success, *address and *size will contain the address and size of
248 * the n-th reserve map entry from the device tree blob, in
249 * native-endian format.
250 *
251 * returns:
252 * 0, on success
253 * -FDT_ERR_BADMAGIC,
254 * -FDT_ERR_BADVERSION,
255 * -FDT_ERR_BADSTATE, standard meanings
256 */
257int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
258
259/**
260 * fdt_subnode_offset_namelen - find a subnode based on substring
261 * @fdt: pointer to the device tree blob
262 * @parentoffset: structure block offset of a node
263 * @name: name of the subnode to locate
264 * @namelen: number of characters of name to consider
265 *
266 * Identical to fdt_subnode_offset(), but only examine the first
267 * namelen characters of name for matching the subnode name. This is
268 * useful for finding subnodes based on a portion of a larger string,
269 * such as a full path.
270 */
271int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
272 const char *name, int namelen);
273/**
274 * fdt_subnode_offset - find a subnode of a given node
275 * @fdt: pointer to the device tree blob
276 * @parentoffset: structure block offset of a node
277 * @name: name of the subnode to locate
278 *
279 * fdt_subnode_offset() finds a subnode of the node at structure block
280 * offset parentoffset with the given name. name may include a unit
281 * address, in which case fdt_subnode_offset() will find the subnode
282 * with that unit address, or the unit address may be omitted, in
283 * which case fdt_subnode_offset() will find an arbitrary subnode
284 * whose name excluding unit address matches the given name.
285 *
286 * returns:
287 * structure block offset of the requested subnode (>=0), on success
288 * -FDT_ERR_NOTFOUND, if the requested subnode does not exist
289 * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
290 * -FDT_ERR_BADMAGIC,
291 * -FDT_ERR_BADVERSION,
292 * -FDT_ERR_BADSTATE,
293 * -FDT_ERR_BADSTRUCTURE,
294 * -FDT_ERR_TRUNCATED, standard meanings.
295 */
296int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
297
298/**
299 * fdt_path_offset - find a tree node by its full path
300 * @fdt: pointer to the device tree blob
301 * @path: full path of the node to locate
302 *
303 * fdt_path_offset() finds a node of a given path in the device tree.
304 * Each path component may omit the unit address portion, but the
305 * results of this are undefined if any such path component is
306 * ambiguous (that is if there are multiple nodes at the relevant
307 * level matching the given component, differentiated only by unit
308 * address).
309 *
310 * returns:
311 * structure block offset of the node with the requested path (>=0), on success
312 * -FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
313 * -FDT_ERR_NOTFOUND, if the requested node does not exist
314 * -FDT_ERR_BADMAGIC,
315 * -FDT_ERR_BADVERSION,
316 * -FDT_ERR_BADSTATE,
317 * -FDT_ERR_BADSTRUCTURE,
318 * -FDT_ERR_TRUNCATED, standard meanings.
319 */
320int fdt_path_offset(const void *fdt, const char *path);
321
322/**
323 * fdt_get_name - retrieve the name of a given node
324 * @fdt: pointer to the device tree blob
325 * @nodeoffset: structure block offset of the starting node
326 * @lenp: pointer to an integer variable (will be overwritten) or NULL
327 *
328 * fdt_get_name() retrieves the name (including unit address) of the
329 * device tree node at structure block offset nodeoffset. If lenp is
330 * non-NULL, the length of this name is also returned, in the integer
331 * pointed to by lenp.
332 *
333 * returns:
334 * pointer to the node's name, on success
335 * If lenp is non-NULL, *lenp contains the length of that name (>=0)
336 * NULL, on error
337 * if lenp is non-NULL *lenp contains an error code (<0):
338 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
339 * -FDT_ERR_BADMAGIC,
340 * -FDT_ERR_BADVERSION,
341 * -FDT_ERR_BADSTATE, standard meanings
342 */
343const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
344
345/**
346 * fdt_first_property_offset - find the offset of a node's first property
347 * @fdt: pointer to the device tree blob
348 * @nodeoffset: structure block offset of a node
349 *
350 * fdt_first_property_offset() finds the first property of the node at
351 * the given structure block offset.
352 *
353 * returns:
354 * structure block offset of the property (>=0), on success
355 * -FDT_ERR_NOTFOUND, if the requested node has no properties
356 * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
357 * -FDT_ERR_BADMAGIC,
358 * -FDT_ERR_BADVERSION,
359 * -FDT_ERR_BADSTATE,
360 * -FDT_ERR_BADSTRUCTURE,
361 * -FDT_ERR_TRUNCATED, standard meanings.
362 */
363int fdt_first_property_offset(const void *fdt, int nodeoffset);
364
365/**
366 * fdt_next_property_offset - step through a node's properties
367 * @fdt: pointer to the device tree blob
368 * @offset: structure block offset of a property
369 *
370 * fdt_next_property_offset() finds the property immediately after the
371 * one at the given structure block offset. This will be a property
372 * of the same node as the given property.
373 *
374 * returns:
375 * structure block offset of the next property (>=0), on success
376 * -FDT_ERR_NOTFOUND, if the given property is the last in its node
377 * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag
378 * -FDT_ERR_BADMAGIC,
379 * -FDT_ERR_BADVERSION,
380 * -FDT_ERR_BADSTATE,
381 * -FDT_ERR_BADSTRUCTURE,
382 * -FDT_ERR_TRUNCATED, standard meanings.
383 */
384int fdt_next_property_offset(const void *fdt, int offset);
385
386/**
387 * fdt_get_property_by_offset - retrieve the property at a given offset
388 * @fdt: pointer to the device tree blob
389 * @offset: offset of the property to retrieve
390 * @lenp: pointer to an integer variable (will be overwritten) or NULL
391 *
392 * fdt_get_property_by_offset() retrieves a pointer to the
393 * fdt_property structure within the device tree blob at the given
394 * offset. If lenp is non-NULL, the length of the property value is
395 * also returned, in the integer pointed to by lenp.
396 *
397 * returns:
398 * pointer to the structure representing the property
399 * if lenp is non-NULL, *lenp contains the length of the property
400 * value (>=0)
401 * NULL, on error
402 * if lenp is non-NULL, *lenp contains an error code (<0):
403 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
404 * -FDT_ERR_BADMAGIC,
405 * -FDT_ERR_BADVERSION,
406 * -FDT_ERR_BADSTATE,
407 * -FDT_ERR_BADSTRUCTURE,
408 * -FDT_ERR_TRUNCATED, standard meanings
409 */
410const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
411 int offset,
412 int *lenp);
413
414/**
415 * fdt_get_property_namelen - find a property based on substring
416 * @fdt: pointer to the device tree blob
417 * @nodeoffset: offset of the node whose property to find
418 * @name: name of the property to find
419 * @namelen: number of characters of name to consider
420 * @lenp: pointer to an integer variable (will be overwritten) or NULL
421 *
422 * Identical to fdt_get_property_namelen(), but only examine the first
423 * namelen characters of name for matching the property name.
424 */
425const struct fdt_property *fdt_get_property_namelen(const void *fdt,
426 int nodeoffset,
427 const char *name,
428 int namelen, int *lenp);
429
430/**
431 * fdt_get_property - find a given property in a given node
432 * @fdt: pointer to the device tree blob
433 * @nodeoffset: offset of the node whose property to find
434 * @name: name of the property to find
435 * @lenp: pointer to an integer variable (will be overwritten) or NULL
436 *
437 * fdt_get_property() retrieves a pointer to the fdt_property
438 * structure within the device tree blob corresponding to the property
439 * named 'name' of the node at offset nodeoffset. If lenp is
440 * non-NULL, the length of the property value is also returned, in the
441 * integer pointed to by lenp.
442 *
443 * returns:
444 * pointer to the structure representing the property
445 * if lenp is non-NULL, *lenp contains the length of the property
446 * value (>=0)
447 * NULL, on error
448 * if lenp is non-NULL, *lenp contains an error code (<0):
449 * -FDT_ERR_NOTFOUND, node does not have named property
450 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
451 * -FDT_ERR_BADMAGIC,
452 * -FDT_ERR_BADVERSION,
453 * -FDT_ERR_BADSTATE,
454 * -FDT_ERR_BADSTRUCTURE,
455 * -FDT_ERR_TRUNCATED, standard meanings
456 */
457const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
458 const char *name, int *lenp);
459static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
460 const char *name,
461 int *lenp)
462{
463 return (struct fdt_property *)(uintptr_t)
464 fdt_get_property(fdt, nodeoffset, name, lenp);
465}
466
467/**
468 * fdt_getprop_by_offset - retrieve the value of a property at a given offset
469 * @fdt: pointer to the device tree blob
470 * @ffset: offset of the property to read
471 * @namep: pointer to a string variable (will be overwritten) or NULL
472 * @lenp: pointer to an integer variable (will be overwritten) or NULL
473 *
474 * fdt_getprop_by_offset() retrieves a pointer to the value of the
475 * property at structure block offset 'offset' (this will be a pointer
476 * to within the device blob itself, not a copy of the value). If
477 * lenp is non-NULL, the length of the property value is also
478 * returned, in the integer pointed to by lenp. If namep is non-NULL,
479 * the property's namne will also be returned in the char * pointed to
480 * by namep (this will be a pointer to within the device tree's string
481 * block, not a new copy of the name).
482 *
483 * returns:
484 * pointer to the property's value
485 * if lenp is non-NULL, *lenp contains the length of the property
486 * value (>=0)
487 * if namep is non-NULL *namep contiains a pointer to the property
488 * name.
489 * NULL, on error
490 * if lenp is non-NULL, *lenp contains an error code (<0):
491 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
492 * -FDT_ERR_BADMAGIC,
493 * -FDT_ERR_BADVERSION,
494 * -FDT_ERR_BADSTATE,
495 * -FDT_ERR_BADSTRUCTURE,
496 * -FDT_ERR_TRUNCATED, standard meanings
497 */
498const void *fdt_getprop_by_offset(const void *fdt, int offset,
499 const char **namep, int *lenp);
500
501/**
502 * fdt_getprop_namelen - get property value based on substring
503 * @fdt: pointer to the device tree blob
504 * @nodeoffset: offset of the node whose property to find
505 * @name: name of the property to find
506 * @namelen: number of characters of name to consider
507 * @lenp: pointer to an integer variable (will be overwritten) or NULL
508 *
509 * Identical to fdt_getprop(), but only examine the first namelen
510 * characters of name for matching the property name.
511 */
512const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
513 const char *name, int namelen, int *lenp);
514
515/**
516 * fdt_getprop - retrieve the value of a given property
517 * @fdt: pointer to the device tree blob
518 * @nodeoffset: offset of the node whose property to find
519 * @name: name of the property to find
520 * @lenp: pointer to an integer variable (will be overwritten) or NULL
521 *
522 * fdt_getprop() retrieves a pointer to the value of the property
523 * named 'name' of the node at offset nodeoffset (this will be a
524 * pointer to within the device blob itself, not a copy of the value).
525 * If lenp is non-NULL, the length of the property value is also
526 * returned, in the integer pointed to by lenp.
527 *
528 * returns:
529 * pointer to the property's value
530 * if lenp is non-NULL, *lenp contains the length of the property
531 * value (>=0)
532 * NULL, on error
533 * if lenp is non-NULL, *lenp contains an error code (<0):
534 * -FDT_ERR_NOTFOUND, node does not have named property
535 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
536 * -FDT_ERR_BADMAGIC,
537 * -FDT_ERR_BADVERSION,
538 * -FDT_ERR_BADSTATE,
539 * -FDT_ERR_BADSTRUCTURE,
540 * -FDT_ERR_TRUNCATED, standard meanings
541 */
542const void *fdt_getprop(const void *fdt, int nodeoffset,
543 const char *name, int *lenp);
544static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
545 const char *name, int *lenp)
546{
547 return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
548}
549
550/**
551 * fdt_get_phandle - retrieve the phandle of a given node
552 * @fdt: pointer to the device tree blob
553 * @nodeoffset: structure block offset of the node
554 *
555 * fdt_get_phandle() retrieves the phandle of the device tree node at
556 * structure block offset nodeoffset.
557 *
558 * returns:
559 * the phandle of the node at nodeoffset, on success (!= 0, != -1)
560 * 0, if the node has no phandle, or another error occurs
561 */
562uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
563
564/**
565 * fdt_get_alias_namelen - get alias based on substring
566 * @fdt: pointer to the device tree blob
567 * @name: name of the alias th look up
568 * @namelen: number of characters of name to consider
569 *
570 * Identical to fdt_get_alias(), but only examine the first namelen
571 * characters of name for matching the alias name.
572 */
573const char *fdt_get_alias_namelen(const void *fdt,
574 const char *name, int namelen);
575
576/**
577 * fdt_get_alias - retreive the path referenced by a given alias
578 * @fdt: pointer to the device tree blob
579 * @name: name of the alias th look up
580 *
581 * fdt_get_alias() retrieves the value of a given alias. That is, the
582 * value of the property named 'name' in the node /aliases.
583 *
584 * returns:
585 * a pointer to the expansion of the alias named 'name', of it exists
586 * NULL, if the given alias or the /aliases node does not exist
587 */
588const char *fdt_get_alias(const void *fdt, const char *name);
589
590/**
591 * fdt_get_path - determine the full path of a node
592 * @fdt: pointer to the device tree blob
593 * @nodeoffset: offset of the node whose path to find
594 * @buf: character buffer to contain the returned path (will be overwritten)
595 * @buflen: size of the character buffer at buf
596 *
597 * fdt_get_path() computes the full path of the node at offset
598 * nodeoffset, and records that path in the buffer at buf.
599 *
600 * NOTE: This function is expensive, as it must scan the device tree
601 * structure from the start to nodeoffset.
602 *
603 * returns:
604 * 0, on success
605 * buf contains the absolute path of the node at
606 * nodeoffset, as a NUL-terminated string.
607 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
608 * -FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
609 * characters and will not fit in the given buffer.
610 * -FDT_ERR_BADMAGIC,
611 * -FDT_ERR_BADVERSION,
612 * -FDT_ERR_BADSTATE,
613 * -FDT_ERR_BADSTRUCTURE, standard meanings
614 */
615int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
616
617/**
618 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
619 * @fdt: pointer to the device tree blob
620 * @nodeoffset: offset of the node whose parent to find
621 * @supernodedepth: depth of the ancestor to find
622 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
623 *
624 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
625 * at a specific depth from the root (where the root itself has depth
626 * 0, its immediate subnodes depth 1 and so forth). So
627 * fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
628 * will always return 0, the offset of the root node. If the node at
629 * nodeoffset has depth D, then:
630 * fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
631 * will return nodeoffset itself.
632 *
633 * NOTE: This function is expensive, as it must scan the device tree
634 * structure from the start to nodeoffset.
635 *
636 * returns:
637
638 * structure block offset of the node at node offset's ancestor
639 * of depth supernodedepth (>=0), on success
640 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
641* -FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of nodeoffset
642 * -FDT_ERR_BADMAGIC,
643 * -FDT_ERR_BADVERSION,
644 * -FDT_ERR_BADSTATE,
645 * -FDT_ERR_BADSTRUCTURE, standard meanings
646 */
647int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
648 int supernodedepth, int *nodedepth);
649
650/**
651 * fdt_node_depth - find the depth of a given node
652 * @fdt: pointer to the device tree blob
653 * @nodeoffset: offset of the node whose parent to find
654 *
655 * fdt_node_depth() finds the depth of a given node. The root node
656 * has depth 0, its immediate subnodes depth 1 and so forth.
657 *
658 * NOTE: This function is expensive, as it must scan the device tree
659 * structure from the start to nodeoffset.
660 *
661 * returns:
662 * depth of the node at nodeoffset (>=0), on success
663 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
664 * -FDT_ERR_BADMAGIC,
665 * -FDT_ERR_BADVERSION,
666 * -FDT_ERR_BADSTATE,
667 * -FDT_ERR_BADSTRUCTURE, standard meanings
668 */
669int fdt_node_depth(const void *fdt, int nodeoffset);
670
671/**
672 * fdt_parent_offset - find the parent of a given node
673 * @fdt: pointer to the device tree blob
674 * @nodeoffset: offset of the node whose parent to find
675 *
676 * fdt_parent_offset() locates the parent node of a given node (that
677 * is, it finds the offset of the node which contains the node at
678 * nodeoffset as a subnode).
679 *
680 * NOTE: This function is expensive, as it must scan the device tree
681 * structure from the start to nodeoffset, *twice*.
682 *
683 * returns:
684 * structure block offset of the parent of the node at nodeoffset
685 * (>=0), on success
686 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
687 * -FDT_ERR_BADMAGIC,
688 * -FDT_ERR_BADVERSION,
689 * -FDT_ERR_BADSTATE,
690 * -FDT_ERR_BADSTRUCTURE, standard meanings
691 */
692int fdt_parent_offset(const void *fdt, int nodeoffset);
693
694/**
695 * fdt_node_offset_by_prop_value - find nodes with a given property value
696 * @fdt: pointer to the device tree blob
697 * @startoffset: only find nodes after this offset
698 * @propname: property name to check
699 * @propval: property value to search for
700 * @proplen: length of the value in propval
701 *
702 * fdt_node_offset_by_prop_value() returns the offset of the first
703 * node after startoffset, which has a property named propname whose
704 * value is of length proplen and has value equal to propval; or if
705 * startoffset is -1, the very first such node in the tree.
706 *
707 * To iterate through all nodes matching the criterion, the following
708 * idiom can be used:
709 * offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
710 * propval, proplen);
711 * while (offset != -FDT_ERR_NOTFOUND) {
712 * // other code here
713 * offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
714 * propval, proplen);
715 * }
716 *
717 * Note the -1 in the first call to the function, if 0 is used here
718 * instead, the function will never locate the root node, even if it
719 * matches the criterion.
720 *
721 * returns:
722 * structure block offset of the located node (>= 0, >startoffset),
723 * on success
724 * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
725 * tree after startoffset
726 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
727 * -FDT_ERR_BADMAGIC,
728 * -FDT_ERR_BADVERSION,
729 * -FDT_ERR_BADSTATE,
730 * -FDT_ERR_BADSTRUCTURE, standard meanings
731 */
732int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
733 const char *propname,
734 const void *propval, int proplen);
735
736/**
737 * fdt_node_offset_by_phandle - find the node with a given phandle
738 * @fdt: pointer to the device tree blob
739 * @phandle: phandle value
740 *
741 * fdt_node_offset_by_phandle() returns the offset of the node
742 * which has the given phandle value. If there is more than one node
743 * in the tree with the given phandle (an invalid tree), results are
744 * undefined.
745 *
746 * returns:
747 * structure block offset of the located node (>= 0), on success
748 * -FDT_ERR_NOTFOUND, no node with that phandle exists
749 * -FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
750 * -FDT_ERR_BADMAGIC,
751 * -FDT_ERR_BADVERSION,
752 * -FDT_ERR_BADSTATE,
753 * -FDT_ERR_BADSTRUCTURE, standard meanings
754 */
755int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
756
757/**
758 * fdt_node_check_compatible: check a node's compatible property
759 * @fdt: pointer to the device tree blob
760 * @nodeoffset: offset of a tree node
761 * @compatible: string to match against
762 *
763 *
764 * fdt_node_check_compatible() returns 0 if the given node contains a
765 * 'compatible' property with the given string as one of its elements,
766 * it returns non-zero otherwise, or on error.
767 *
768 * returns:
769 * 0, if the node has a 'compatible' property listing the given string
770 * 1, if the node has a 'compatible' property, but it does not list
771 * the given string
772 * -FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
773 * -FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
774 * -FDT_ERR_BADMAGIC,
775 * -FDT_ERR_BADVERSION,
776 * -FDT_ERR_BADSTATE,
777 * -FDT_ERR_BADSTRUCTURE, standard meanings
778 */
779int fdt_node_check_compatible(const void *fdt, int nodeoffset,
780 const char *compatible);
781
782/**
783 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
784 * @fdt: pointer to the device tree blob
785 * @startoffset: only find nodes after this offset
786 * @compatible: 'compatible' string to match against
787 *
788 * fdt_node_offset_by_compatible() returns the offset of the first
789 * node after startoffset, which has a 'compatible' property which
790 * lists the given compatible string; or if startoffset is -1, the
791 * very first such node in the tree.
792 *
793 * To iterate through all nodes matching the criterion, the following
794 * idiom can be used:
795 * offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
796 * while (offset != -FDT_ERR_NOTFOUND) {
797 * // other code here
798 * offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
799 * }
800 *
801 * Note the -1 in the first call to the function, if 0 is used here
802 * instead, the function will never locate the root node, even if it
803 * matches the criterion.
804 *
805 * returns:
806 * structure block offset of the located node (>= 0, >startoffset),
807 * on success
808 * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
809 * tree after startoffset
810 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
811 * -FDT_ERR_BADMAGIC,
812 * -FDT_ERR_BADVERSION,
813 * -FDT_ERR_BADSTATE,
814 * -FDT_ERR_BADSTRUCTURE, standard meanings
815 */
816int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
817 const char *compatible);
818
819/**********************************************************************/
820/* Write-in-place functions */
821/**********************************************************************/
822
823/**
824 * fdt_setprop_inplace - change a property's value, but not its size
825 * @fdt: pointer to the device tree blob
826 * @nodeoffset: offset of the node whose property to change
827 * @name: name of the property to change
828 * @val: pointer to data to replace the property value with
829 * @len: length of the property value
830 *
831 * fdt_setprop_inplace() replaces the value of a given property with
832 * the data in val, of length len. This function cannot change the
833 * size of a property, and so will only work if len is equal to the
834 * current length of the property.
835 *
836 * This function will alter only the bytes in the blob which contain
837 * the given property value, and will not alter or move any other part
838 * of the tree.
839 *
840 * returns:
841 * 0, on success
842 * -FDT_ERR_NOSPACE, if len is not equal to the property's current length
843 * -FDT_ERR_NOTFOUND, node does not have the named property
844 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
845 * -FDT_ERR_BADMAGIC,
846 * -FDT_ERR_BADVERSION,
847 * -FDT_ERR_BADSTATE,
848 * -FDT_ERR_BADSTRUCTURE,
849 * -FDT_ERR_TRUNCATED, standard meanings
850 */
851int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
852 const void *val, int len);
853
854/**
855 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
856 * @fdt: pointer to the device tree blob
857 * @nodeoffset: offset of the node whose property to change
858 * @name: name of the property to change
859 * @val: 32-bit integer value to replace the property with
860 *
861 * fdt_setprop_inplace_u32() replaces the value of a given property
862 * with the 32-bit integer value in val, converting val to big-endian
863 * if necessary. This function cannot change the size of a property,
864 * and so will only work if the property already exists and has length
865 * 4.
866 *
867 * This function will alter only the bytes in the blob which contain
868 * the given property value, and will not alter or move any other part
869 * of the tree.
870 *
871 * returns:
872 * 0, on success
873 * -FDT_ERR_NOSPACE, if the property's length is not equal to 4
874 * -FDT_ERR_NOTFOUND, node does not have the named property
875 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
876 * -FDT_ERR_BADMAGIC,
877 * -FDT_ERR_BADVERSION,
878 * -FDT_ERR_BADSTATE,
879 * -FDT_ERR_BADSTRUCTURE,
880 * -FDT_ERR_TRUNCATED, standard meanings
881 */
882static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
883 const char *name, uint32_t val)
884{
885 val = cpu_to_fdt32(val);
886 return fdt_setprop_inplace(fdt, nodeoffset, name, &val, sizeof(val));
887}
888
889/**
890 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
891 * @fdt: pointer to the device tree blob
892 * @nodeoffset: offset of the node whose property to change
893 * @name: name of the property to change
894 * @val: 64-bit integer value to replace the property with
895 *
896 * fdt_setprop_inplace_u64() replaces the value of a given property
897 * with the 64-bit integer value in val, converting val to big-endian
898 * if necessary. This function cannot change the size of a property,
899 * and so will only work if the property already exists and has length
900 * 8.
901 *
902 * This function will alter only the bytes in the blob which contain
903 * the given property value, and will not alter or move any other part
904 * of the tree.
905 *
906 * returns:
907 * 0, on success
908 * -FDT_ERR_NOSPACE, if the property's length is not equal to 8
909 * -FDT_ERR_NOTFOUND, node does not have the named property
910 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
911 * -FDT_ERR_BADMAGIC,
912 * -FDT_ERR_BADVERSION,
913 * -FDT_ERR_BADSTATE,
914 * -FDT_ERR_BADSTRUCTURE,
915 * -FDT_ERR_TRUNCATED, standard meanings
916 */
917static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
918 const char *name, uint64_t val)
919{
920 val = cpu_to_fdt64(val);
921 return fdt_setprop_inplace(fdt, nodeoffset, name, &val, sizeof(val));
922}
923
924/**
925 * fdt_setprop_inplace_cell - change the value of a single-cell property
926 *
927 * This is an alternative name for fdt_setprop_inplace_u32()
928 */
929static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
930 const char *name, uint32_t val)
931{
932 return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
933}
934
935/**
936 * fdt_nop_property - replace a property with nop tags
937 * @fdt: pointer to the device tree blob
938 * @nodeoffset: offset of the node whose property to nop
939 * @name: name of the property to nop
940 *
941 * fdt_nop_property() will replace a given property's representation
942 * in the blob with FDT_NOP tags, effectively removing it from the
943 * tree.
944 *
945 * This function will alter only the bytes in the blob which contain
946 * the property, and will not alter or move any other part of the
947 * tree.
948 *
949 * returns:
950 * 0, on success
951 * -FDT_ERR_NOTFOUND, node does not have the named property
952 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
953 * -FDT_ERR_BADMAGIC,
954 * -FDT_ERR_BADVERSION,
955 * -FDT_ERR_BADSTATE,
956 * -FDT_ERR_BADSTRUCTURE,
957 * -FDT_ERR_TRUNCATED, standard meanings
958 */
959int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
960
961/**
962 * fdt_nop_node - replace a node (subtree) with nop tags
963 * @fdt: pointer to the device tree blob
964 * @nodeoffset: offset of the node to nop
965 *
966 * fdt_nop_node() will replace a given node's representation in the
967 * blob, including all its subnodes, if any, with FDT_NOP tags,
968 * effectively removing it from the tree.
969 *
970 * This function will alter only the bytes in the blob which contain
971 * the node and its properties and subnodes, and will not alter or
972 * move any other part of the tree.
973 *
974 * returns:
975 * 0, on success
976 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
977 * -FDT_ERR_BADMAGIC,
978 * -FDT_ERR_BADVERSION,
979 * -FDT_ERR_BADSTATE,
980 * -FDT_ERR_BADSTRUCTURE,
981 * -FDT_ERR_TRUNCATED, standard meanings
982 */
983int fdt_nop_node(void *fdt, int nodeoffset);
984
985/**********************************************************************/
986/* Sequential write functions */
987/**********************************************************************/
988
989int fdt_create(void *buf, int bufsize);
990int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
991int fdt_finish_reservemap(void *fdt);
992int fdt_begin_node(void *fdt, const char *name);
993int fdt_property(void *fdt, const char *name, const void *val, int len);
994static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
995{
996 val = cpu_to_fdt32(val);
997 return fdt_property(fdt, name, &val, sizeof(val));
998}
999static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
1000{
1001 val = cpu_to_fdt64(val);
1002 return fdt_property(fdt, name, &val, sizeof(val));
1003}
1004static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
1005{
1006 return fdt_property_u32(fdt, name, val);
1007}
1008#define fdt_property_string(fdt, name, str) \
1009 fdt_property(fdt, name, str, strlen(str)+1)
1010int fdt_end_node(void *fdt);
1011int fdt_finish(void *fdt);
1012
1013/**********************************************************************/
1014/* Read-write functions */
1015/**********************************************************************/
1016
1017int fdt_create_empty_tree(void *buf, int bufsize);
1018int fdt_open_into(const void *fdt, void *buf, int bufsize);
1019int fdt_pack(void *fdt);
1020
1021/**
1022 * fdt_add_mem_rsv - add one memory reserve map entry
1023 * @fdt: pointer to the device tree blob
1024 * @address, @size: 64-bit values (native endian)
1025 *
1026 * Adds a reserve map entry to the given blob reserving a region at
1027 * address address of length size.
1028 *
1029 * This function will insert data into the reserve map and will
1030 * therefore change the indexes of some entries in the table.
1031 *
1032 * returns:
1033 * 0, on success
1034 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1035 * contain the new reservation entry
1036 * -FDT_ERR_BADMAGIC,
1037 * -FDT_ERR_BADVERSION,
1038 * -FDT_ERR_BADSTATE,
1039 * -FDT_ERR_BADSTRUCTURE,
1040 * -FDT_ERR_BADLAYOUT,
1041 * -FDT_ERR_TRUNCATED, standard meanings
1042 */
1043int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
1044
1045/**
1046 * fdt_del_mem_rsv - remove a memory reserve map entry
1047 * @fdt: pointer to the device tree blob
1048 * @n: entry to remove
1049 *
1050 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
1051 * the blob.
1052 *
1053 * This function will delete data from the reservation table and will
1054 * therefore change the indexes of some entries in the table.
1055 *
1056 * returns:
1057 * 0, on success
1058 * -FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
1059 * are less than n+1 reserve map entries)
1060 * -FDT_ERR_BADMAGIC,
1061 * -FDT_ERR_BADVERSION,
1062 * -FDT_ERR_BADSTATE,
1063 * -FDT_ERR_BADSTRUCTURE,
1064 * -FDT_ERR_BADLAYOUT,
1065 * -FDT_ERR_TRUNCATED, standard meanings
1066 */
1067int fdt_del_mem_rsv(void *fdt, int n);
1068
1069/**
1070 * fdt_set_name - change the name of a given node
1071 * @fdt: pointer to the device tree blob
1072 * @nodeoffset: structure block offset of a node
1073 * @name: name to give the node
1074 *
1075 * fdt_set_name() replaces the name (including unit address, if any)
1076 * of the given node with the given string. NOTE: this function can't
1077 * efficiently check if the new name is unique amongst the given
1078 * node's siblings; results are undefined if this function is invoked
1079 * with a name equal to one of the given node's siblings.
1080 *
1081 * This function may insert or delete data from the blob, and will
1082 * therefore change the offsets of some existing nodes.
1083 *
1084 * returns:
1085 * 0, on success
1086 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob
1087 * to contain the new name
1088 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1089 * -FDT_ERR_BADMAGIC,
1090 * -FDT_ERR_BADVERSION,
1091 * -FDT_ERR_BADSTATE, standard meanings
1092 */
1093int fdt_set_name(void *fdt, int nodeoffset, const char *name);
1094
1095/**
1096 * fdt_setprop - create or change a property
1097 * @fdt: pointer to the device tree blob
1098 * @nodeoffset: offset of the node whose property to change
1099 * @name: name of the property to change
1100 * @val: pointer to data to set the property value to
1101 * @len: length of the property value
1102 *
1103 * fdt_setprop() sets the value of the named property in the given
1104 * node to the given value and length, creating the property if it
1105 * does not already exist.
1106 *
1107 * This function may insert or delete data from the blob, and will
1108 * therefore change the offsets of some existing nodes.
1109 *
1110 * returns:
1111 * 0, on success
1112 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1113 * contain the new property value
1114 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1115 * -FDT_ERR_BADLAYOUT,
1116 * -FDT_ERR_BADMAGIC,
1117 * -FDT_ERR_BADVERSION,
1118 * -FDT_ERR_BADSTATE,
1119 * -FDT_ERR_BADSTRUCTURE,
1120 * -FDT_ERR_BADLAYOUT,
1121 * -FDT_ERR_TRUNCATED, standard meanings
1122 */
1123int fdt_setprop(void *fdt, int nodeoffset, const char *name,
1124 const void *val, int len);
1125
1126/**
1127 * fdt_setprop_u32 - set a property to a 32-bit integer
1128 * @fdt: pointer to the device tree blob
1129 * @nodeoffset: offset of the node whose property to change
1130 * @name: name of the property to change
1131 * @val: 32-bit integer value for the property (native endian)
1132 *
1133 * fdt_setprop_u32() sets the value of the named property in the given
1134 * node to the given 32-bit integer value (converting to big-endian if
1135 * necessary), or creates a new property with that value if it does
1136 * not already exist.
1137 *
1138 * This function may insert or delete data from the blob, and will
1139 * therefore change the offsets of some existing nodes.
1140 *
1141 * returns:
1142 * 0, on success
1143 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1144 * contain the new property value
1145 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1146 * -FDT_ERR_BADLAYOUT,
1147 * -FDT_ERR_BADMAGIC,
1148 * -FDT_ERR_BADVERSION,
1149 * -FDT_ERR_BADSTATE,
1150 * -FDT_ERR_BADSTRUCTURE,
1151 * -FDT_ERR_BADLAYOUT,
1152 * -FDT_ERR_TRUNCATED, standard meanings
1153 */
1154static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
1155 uint32_t val)
1156{
1157 val = cpu_to_fdt32(val);
1158 return fdt_setprop(fdt, nodeoffset, name, &val, sizeof(val));
1159}
1160
1161/**
1162 * fdt_setprop_u64 - set a property to a 64-bit integer
1163 * @fdt: pointer to the device tree blob
1164 * @nodeoffset: offset of the node whose property to change
1165 * @name: name of the property to change
1166 * @val: 64-bit integer value for the property (native endian)
1167 *
1168 * fdt_setprop_u64() sets the value of the named property in the given
1169 * node to the given 64-bit integer value (converting to big-endian if
1170 * necessary), or creates a new property with that value if it does
1171 * not already exist.
1172 *
1173 * This function may insert or delete data from the blob, and will
1174 * therefore change the offsets of some existing nodes.
1175 *
1176 * returns:
1177 * 0, on success
1178 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1179 * contain the new property value
1180 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1181 * -FDT_ERR_BADLAYOUT,
1182 * -FDT_ERR_BADMAGIC,
1183 * -FDT_ERR_BADVERSION,
1184 * -FDT_ERR_BADSTATE,
1185 * -FDT_ERR_BADSTRUCTURE,
1186 * -FDT_ERR_BADLAYOUT,
1187 * -FDT_ERR_TRUNCATED, standard meanings
1188 */
1189static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
1190 uint64_t val)
1191{
1192 val = cpu_to_fdt64(val);
1193 return fdt_setprop(fdt, nodeoffset, name, &val, sizeof(val));
1194}
1195
1196/**
1197 * fdt_setprop_cell - set a property to a single cell value
1198 *
1199 * This is an alternative name for fdt_setprop_u32()
1200 */
1201static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
1202 uint32_t val)
1203{
1204 return fdt_setprop_u32(fdt, nodeoffset, name, val);
1205}
1206
1207/**
1208 * fdt_setprop_string - set a property to a string value
1209 * @fdt: pointer to the device tree blob
1210 * @nodeoffset: offset of the node whose property to change
1211 * @name: name of the property to change
1212 * @str: string value for the property
1213 *
1214 * fdt_setprop_string() sets the value of the named property in the
1215 * given node to the given string value (using the length of the
1216 * string to determine the new length of the property), or creates a
1217 * new property with that value if it does not already exist.
1218 *
1219 * This function may insert or delete data from the blob, and will
1220 * therefore change the offsets of some existing nodes.
1221 *
1222 * returns:
1223 * 0, on success
1224 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1225 * contain the new property value
1226 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1227 * -FDT_ERR_BADLAYOUT,
1228 * -FDT_ERR_BADMAGIC,
1229 * -FDT_ERR_BADVERSION,
1230 * -FDT_ERR_BADSTATE,
1231 * -FDT_ERR_BADSTRUCTURE,
1232 * -FDT_ERR_BADLAYOUT,
1233 * -FDT_ERR_TRUNCATED, standard meanings
1234 */
1235#define fdt_setprop_string(fdt, nodeoffset, name, str) \
1236 fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1237
1238/**
1239 * fdt_appendprop - append to or create a property
1240 * @fdt: pointer to the device tree blob
1241 * @nodeoffset: offset of the node whose property to change
1242 * @name: name of the property to append to
1243 * @val: pointer to data to append to the property value
1244 * @len: length of the data to append to the property value
1245 *
1246 * fdt_appendprop() appends the value to the named property in the
1247 * given node, creating the property if it does not already exist.
1248 *
1249 * This function may insert data into the blob, and will therefore
1250 * change the offsets of some existing nodes.
1251 *
1252 * returns:
1253 * 0, on success
1254 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1255 * contain the new property value
1256 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1257 * -FDT_ERR_BADLAYOUT,
1258 * -FDT_ERR_BADMAGIC,
1259 * -FDT_ERR_BADVERSION,
1260 * -FDT_ERR_BADSTATE,
1261 * -FDT_ERR_BADSTRUCTURE,
1262 * -FDT_ERR_BADLAYOUT,
1263 * -FDT_ERR_TRUNCATED, standard meanings
1264 */
1265int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
1266 const void *val, int len);
1267
1268/**
1269 * fdt_appendprop_u32 - append a 32-bit integer value to a property
1270 * @fdt: pointer to the device tree blob
1271 * @nodeoffset: offset of the node whose property to change
1272 * @name: name of the property to change
1273 * @val: 32-bit integer value to append to the property (native endian)
1274 *
1275 * fdt_appendprop_u32() appends the given 32-bit integer value
1276 * (converting to big-endian if necessary) to the value of the named
1277 * property in the given node, or creates a new property with that
1278 * value if it does not already exist.
1279 *
1280 * This function may insert data into the blob, and will therefore
1281 * change the offsets of some existing nodes.
1282 *
1283 * returns:
1284 * 0, on success
1285 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1286 * contain the new property value
1287 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1288 * -FDT_ERR_BADLAYOUT,
1289 * -FDT_ERR_BADMAGIC,
1290 * -FDT_ERR_BADVERSION,
1291 * -FDT_ERR_BADSTATE,
1292 * -FDT_ERR_BADSTRUCTURE,
1293 * -FDT_ERR_BADLAYOUT,
1294 * -FDT_ERR_TRUNCATED, standard meanings
1295 */
1296static inline int fdt_appendprop_u32(void *fdt, int nodeoffset,
1297 const char *name, uint32_t val)
1298{
1299 val = cpu_to_fdt32(val);
1300 return fdt_appendprop(fdt, nodeoffset, name, &val, sizeof(val));
1301}
1302
1303/**
1304 * fdt_appendprop_u64 - append a 64-bit integer value to a property
1305 * @fdt: pointer to the device tree blob
1306 * @nodeoffset: offset of the node whose property to change
1307 * @name: name of the property to change
1308 * @val: 64-bit integer value to append to the property (native endian)
1309 *
1310 * fdt_appendprop_u64() appends the given 64-bit integer value
1311 * (converting to big-endian if necessary) to the value of the named
1312 * property in the given node, or creates a new property with that
1313 * value if it does not already exist.
1314 *
1315 * This function may insert data into the blob, and will therefore
1316 * change the offsets of some existing nodes.
1317 *
1318 * returns:
1319 * 0, on success
1320 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1321 * contain the new property value
1322 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1323 * -FDT_ERR_BADLAYOUT,
1324 * -FDT_ERR_BADMAGIC,
1325 * -FDT_ERR_BADVERSION,
1326 * -FDT_ERR_BADSTATE,
1327 * -FDT_ERR_BADSTRUCTURE,
1328 * -FDT_ERR_BADLAYOUT,
1329 * -FDT_ERR_TRUNCATED, standard meanings
1330 */
1331static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
1332 const char *name, uint64_t val)
1333{
1334 val = cpu_to_fdt64(val);
1335 return fdt_appendprop(fdt, nodeoffset, name, &val, sizeof(val));
1336}
1337
1338/**
1339 * fdt_appendprop_cell - append a single cell value to a property
1340 *
1341 * This is an alternative name for fdt_appendprop_u32()
1342 */
1343static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
1344 const char *name, uint32_t val)
1345{
1346 return fdt_appendprop_u32(fdt, nodeoffset, name, val);
1347}
1348
1349/**
1350 * fdt_appendprop_string - append a string to a property
1351 * @fdt: pointer to the device tree blob
1352 * @nodeoffset: offset of the node whose property to change
1353 * @name: name of the property to change
1354 * @str: string value to append to the property
1355 *
1356 * fdt_appendprop_string() appends the given string to the value of
1357 * the named property in the given node, or creates a new property
1358 * with that value if it does not already exist.
1359 *
1360 * This function may insert data into the blob, and will therefore
1361 * change the offsets of some existing nodes.
1362 *
1363 * returns:
1364 * 0, on success
1365 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1366 * contain the new property value
1367 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1368 * -FDT_ERR_BADLAYOUT,
1369 * -FDT_ERR_BADMAGIC,
1370 * -FDT_ERR_BADVERSION,
1371 * -FDT_ERR_BADSTATE,
1372 * -FDT_ERR_BADSTRUCTURE,
1373 * -FDT_ERR_BADLAYOUT,
1374 * -FDT_ERR_TRUNCATED, standard meanings
1375 */
1376#define fdt_appendprop_string(fdt, nodeoffset, name, str) \
1377 fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1378
1379/**
1380 * fdt_delprop - delete a property
1381 * @fdt: pointer to the device tree blob
1382 * @nodeoffset: offset of the node whose property to nop
1383 * @name: name of the property to nop
1384 *
1385 * fdt_del_property() will delete the given property.
1386 *
1387 * This function will delete data from the blob, and will therefore
1388 * change the offsets of some existing nodes.
1389 *
1390 * returns:
1391 * 0, on success
1392 * -FDT_ERR_NOTFOUND, node does not have the named property
1393 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1394 * -FDT_ERR_BADLAYOUT,
1395 * -FDT_ERR_BADMAGIC,
1396 * -FDT_ERR_BADVERSION,
1397 * -FDT_ERR_BADSTATE,
1398 * -FDT_ERR_BADSTRUCTURE,
1399 * -FDT_ERR_TRUNCATED, standard meanings
1400 */
1401int fdt_delprop(void *fdt, int nodeoffset, const char *name);
1402
1403/**
1404 * fdt_add_subnode_namelen - creates a new node based on substring
1405 * @fdt: pointer to the device tree blob
1406 * @parentoffset: structure block offset of a node
1407 * @name: name of the subnode to locate
1408 * @namelen: number of characters of name to consider
1409 *
1410 * Identical to fdt_add_subnode(), but use only the first namelen
1411 * characters of name as the name of the new node. This is useful for
1412 * creating subnodes based on a portion of a larger string, such as a
1413 * full path.
1414 */
1415int fdt_add_subnode_namelen(void *fdt, int parentoffset,
1416 const char *name, int namelen);
1417
1418/**
1419 * fdt_add_subnode - creates a new node
1420 * @fdt: pointer to the device tree blob
1421 * @parentoffset: structure block offset of a node
1422 * @name: name of the subnode to locate
1423 *
1424 * fdt_add_subnode() creates a new node as a subnode of the node at
1425 * structure block offset parentoffset, with the given name (which
1426 * should include the unit address, if any).
1427 *
1428 * This function will insert data into the blob, and will therefore
1429 * change the offsets of some existing nodes.
1430
1431 * returns:
1432 * structure block offset of the created nodeequested subnode (>=0), on success
1433 * -FDT_ERR_NOTFOUND, if the requested subnode does not exist
1434 * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
1435 * -FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
1436 * the given name
1437 * -FDT_ERR_NOSPACE, if there is insufficient free space in the
1438 * blob to contain the new node
1439 * -FDT_ERR_NOSPACE
1440 * -FDT_ERR_BADLAYOUT
1441 * -FDT_ERR_BADMAGIC,
1442 * -FDT_ERR_BADVERSION,
1443 * -FDT_ERR_BADSTATE,
1444 * -FDT_ERR_BADSTRUCTURE,
1445 * -FDT_ERR_TRUNCATED, standard meanings.
1446 */
1447int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
1448
1449/**
1450 * fdt_del_node - delete a node (subtree)
1451 * @fdt: pointer to the device tree blob
1452 * @nodeoffset: offset of the node to nop
1453 *
1454 * fdt_del_node() will remove the given node, including all its
1455 * subnodes if any, from the blob.
1456 *
1457 * This function will delete data from the blob, and will therefore
1458 * change the offsets of some existing nodes.
1459 *
1460 * returns:
1461 * 0, on success
1462 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1463 * -FDT_ERR_BADLAYOUT,
1464 * -FDT_ERR_BADMAGIC,
1465 * -FDT_ERR_BADVERSION,
1466 * -FDT_ERR_BADSTATE,
1467 * -FDT_ERR_BADSTRUCTURE,
1468 * -FDT_ERR_TRUNCATED, standard meanings
1469 */
1470int fdt_del_node(void *fdt, int nodeoffset);
1471
1472/**********************************************************************/
1473/* Debugging / informational functions */
1474/**********************************************************************/
1475
1476const char *fdt_strerror(int errval);
1477
1478#endif /* _LIBFDT_H */
1/* SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause) */
2#ifndef LIBFDT_H
3#define LIBFDT_H
4/*
5 * libfdt - Flat Device Tree manipulation
6 * Copyright (C) 2006 David Gibson, IBM Corporation.
7 */
8
9#include "libfdt_env.h"
10#include "fdt.h"
11
12#ifdef __cplusplus
13extern "C" {
14#endif
15
16#define FDT_FIRST_SUPPORTED_VERSION 0x02
17#define FDT_LAST_COMPATIBLE_VERSION 0x10
18#define FDT_LAST_SUPPORTED_VERSION 0x11
19
20/* Error codes: informative error codes */
21#define FDT_ERR_NOTFOUND 1
22 /* FDT_ERR_NOTFOUND: The requested node or property does not exist */
23#define FDT_ERR_EXISTS 2
24 /* FDT_ERR_EXISTS: Attempted to create a node or property which
25 * already exists */
26#define FDT_ERR_NOSPACE 3
27 /* FDT_ERR_NOSPACE: Operation needed to expand the device
28 * tree, but its buffer did not have sufficient space to
29 * contain the expanded tree. Use fdt_open_into() to move the
30 * device tree to a buffer with more space. */
31
32/* Error codes: codes for bad parameters */
33#define FDT_ERR_BADOFFSET 4
34 /* FDT_ERR_BADOFFSET: Function was passed a structure block
35 * offset which is out-of-bounds, or which points to an
36 * unsuitable part of the structure for the operation. */
37#define FDT_ERR_BADPATH 5
38 /* FDT_ERR_BADPATH: Function was passed a badly formatted path
39 * (e.g. missing a leading / for a function which requires an
40 * absolute path) */
41#define FDT_ERR_BADPHANDLE 6
42 /* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle.
43 * This can be caused either by an invalid phandle property
44 * length, or the phandle value was either 0 or -1, which are
45 * not permitted. */
46#define FDT_ERR_BADSTATE 7
47 /* FDT_ERR_BADSTATE: Function was passed an incomplete device
48 * tree created by the sequential-write functions, which is
49 * not sufficiently complete for the requested operation. */
50
51/* Error codes: codes for bad device tree blobs */
52#define FDT_ERR_TRUNCATED 8
53 /* FDT_ERR_TRUNCATED: FDT or a sub-block is improperly
54 * terminated (overflows, goes outside allowed bounds, or
55 * isn't properly terminated). */
56#define FDT_ERR_BADMAGIC 9
57 /* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
58 * device tree at all - it is missing the flattened device
59 * tree magic number. */
60#define FDT_ERR_BADVERSION 10
61 /* FDT_ERR_BADVERSION: Given device tree has a version which
62 * can't be handled by the requested operation. For
63 * read-write functions, this may mean that fdt_open_into() is
64 * required to convert the tree to the expected version. */
65#define FDT_ERR_BADSTRUCTURE 11
66 /* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt
67 * structure block or other serious error (e.g. misnested
68 * nodes, or subnodes preceding properties). */
69#define FDT_ERR_BADLAYOUT 12
70 /* FDT_ERR_BADLAYOUT: For read-write functions, the given
71 * device tree has it's sub-blocks in an order that the
72 * function can't handle (memory reserve map, then structure,
73 * then strings). Use fdt_open_into() to reorganize the tree
74 * into a form suitable for the read-write operations. */
75
76/* "Can't happen" error indicating a bug in libfdt */
77#define FDT_ERR_INTERNAL 13
78 /* FDT_ERR_INTERNAL: libfdt has failed an internal assertion.
79 * Should never be returned, if it is, it indicates a bug in
80 * libfdt itself. */
81
82/* Errors in device tree content */
83#define FDT_ERR_BADNCELLS 14
84 /* FDT_ERR_BADNCELLS: Device tree has a #address-cells, #size-cells
85 * or similar property with a bad format or value */
86
87#define FDT_ERR_BADVALUE 15
88 /* FDT_ERR_BADVALUE: Device tree has a property with an unexpected
89 * value. For example: a property expected to contain a string list
90 * is not NUL-terminated within the length of its value. */
91
92#define FDT_ERR_BADOVERLAY 16
93 /* FDT_ERR_BADOVERLAY: The device tree overlay, while
94 * correctly structured, cannot be applied due to some
95 * unexpected or missing value, property or node. */
96
97#define FDT_ERR_NOPHANDLES 17
98 /* FDT_ERR_NOPHANDLES: The device tree doesn't have any
99 * phandle available anymore without causing an overflow */
100
101#define FDT_ERR_BADFLAGS 18
102 /* FDT_ERR_BADFLAGS: The function was passed a flags field that
103 * contains invalid flags or an invalid combination of flags. */
104
105#define FDT_ERR_ALIGNMENT 19
106 /* FDT_ERR_ALIGNMENT: The device tree base address is not 8-byte
107 * aligned. */
108
109#define FDT_ERR_MAX 19
110
111/* constants */
112#define FDT_MAX_PHANDLE 0xfffffffe
113 /* Valid values for phandles range from 1 to 2^32-2. */
114
115/**********************************************************************/
116/* Low-level functions (you probably don't need these) */
117/**********************************************************************/
118
119#ifndef SWIG /* This function is not useful in Python */
120const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen);
121#endif
122static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
123{
124 return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
125}
126
127uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
128
129/*
130 * External helpers to access words from a device tree blob. They're built
131 * to work even with unaligned pointers on platforms (such as ARMv5) that don't
132 * like unaligned loads and stores.
133 */
134static inline uint32_t fdt32_ld(const fdt32_t *p)
135{
136 const uint8_t *bp = (const uint8_t *)p;
137
138 return ((uint32_t)bp[0] << 24)
139 | ((uint32_t)bp[1] << 16)
140 | ((uint32_t)bp[2] << 8)
141 | bp[3];
142}
143
144static inline void fdt32_st(void *property, uint32_t value)
145{
146 uint8_t *bp = (uint8_t *)property;
147
148 bp[0] = value >> 24;
149 bp[1] = (value >> 16) & 0xff;
150 bp[2] = (value >> 8) & 0xff;
151 bp[3] = value & 0xff;
152}
153
154static inline uint64_t fdt64_ld(const fdt64_t *p)
155{
156 const uint8_t *bp = (const uint8_t *)p;
157
158 return ((uint64_t)bp[0] << 56)
159 | ((uint64_t)bp[1] << 48)
160 | ((uint64_t)bp[2] << 40)
161 | ((uint64_t)bp[3] << 32)
162 | ((uint64_t)bp[4] << 24)
163 | ((uint64_t)bp[5] << 16)
164 | ((uint64_t)bp[6] << 8)
165 | bp[7];
166}
167
168static inline void fdt64_st(void *property, uint64_t value)
169{
170 uint8_t *bp = (uint8_t *)property;
171
172 bp[0] = value >> 56;
173 bp[1] = (value >> 48) & 0xff;
174 bp[2] = (value >> 40) & 0xff;
175 bp[3] = (value >> 32) & 0xff;
176 bp[4] = (value >> 24) & 0xff;
177 bp[5] = (value >> 16) & 0xff;
178 bp[6] = (value >> 8) & 0xff;
179 bp[7] = value & 0xff;
180}
181
182/**********************************************************************/
183/* Traversal functions */
184/**********************************************************************/
185
186int fdt_next_node(const void *fdt, int offset, int *depth);
187
188/**
189 * fdt_first_subnode() - get offset of first direct subnode
190 * @fdt: FDT blob
191 * @offset: Offset of node to check
192 *
193 * Return: offset of first subnode, or -FDT_ERR_NOTFOUND if there is none
194 */
195int fdt_first_subnode(const void *fdt, int offset);
196
197/**
198 * fdt_next_subnode() - get offset of next direct subnode
199 * @fdt: FDT blob
200 * @offset: Offset of previous subnode
201 *
202 * After first calling fdt_first_subnode(), call this function repeatedly to
203 * get direct subnodes of a parent node.
204 *
205 * Return: offset of next subnode, or -FDT_ERR_NOTFOUND if there are no more
206 * subnodes
207 */
208int fdt_next_subnode(const void *fdt, int offset);
209
210/**
211 * fdt_for_each_subnode - iterate over all subnodes of a parent
212 *
213 * @node: child node (int, lvalue)
214 * @fdt: FDT blob (const void *)
215 * @parent: parent node (int)
216 *
217 * This is actually a wrapper around a for loop and would be used like so:
218 *
219 * fdt_for_each_subnode(node, fdt, parent) {
220 * Use node
221 * ...
222 * }
223 *
224 * if ((node < 0) && (node != -FDT_ERR_NOTFOUND)) {
225 * Error handling
226 * }
227 *
228 * Note that this is implemented as a macro and @node is used as
229 * iterator in the loop. The parent variable be constant or even a
230 * literal.
231 */
232#define fdt_for_each_subnode(node, fdt, parent) \
233 for (node = fdt_first_subnode(fdt, parent); \
234 node >= 0; \
235 node = fdt_next_subnode(fdt, node))
236
237/**********************************************************************/
238/* General functions */
239/**********************************************************************/
240#define fdt_get_header(fdt, field) \
241 (fdt32_ld(&((const struct fdt_header *)(fdt))->field))
242#define fdt_magic(fdt) (fdt_get_header(fdt, magic))
243#define fdt_totalsize(fdt) (fdt_get_header(fdt, totalsize))
244#define fdt_off_dt_struct(fdt) (fdt_get_header(fdt, off_dt_struct))
245#define fdt_off_dt_strings(fdt) (fdt_get_header(fdt, off_dt_strings))
246#define fdt_off_mem_rsvmap(fdt) (fdt_get_header(fdt, off_mem_rsvmap))
247#define fdt_version(fdt) (fdt_get_header(fdt, version))
248#define fdt_last_comp_version(fdt) (fdt_get_header(fdt, last_comp_version))
249#define fdt_boot_cpuid_phys(fdt) (fdt_get_header(fdt, boot_cpuid_phys))
250#define fdt_size_dt_strings(fdt) (fdt_get_header(fdt, size_dt_strings))
251#define fdt_size_dt_struct(fdt) (fdt_get_header(fdt, size_dt_struct))
252
253#define fdt_set_hdr_(name) \
254 static inline void fdt_set_##name(void *fdt, uint32_t val) \
255 { \
256 struct fdt_header *fdth = (struct fdt_header *)fdt; \
257 fdth->name = cpu_to_fdt32(val); \
258 }
259fdt_set_hdr_(magic);
260fdt_set_hdr_(totalsize);
261fdt_set_hdr_(off_dt_struct);
262fdt_set_hdr_(off_dt_strings);
263fdt_set_hdr_(off_mem_rsvmap);
264fdt_set_hdr_(version);
265fdt_set_hdr_(last_comp_version);
266fdt_set_hdr_(boot_cpuid_phys);
267fdt_set_hdr_(size_dt_strings);
268fdt_set_hdr_(size_dt_struct);
269#undef fdt_set_hdr_
270
271/**
272 * fdt_header_size - return the size of the tree's header
273 * @fdt: pointer to a flattened device tree
274 *
275 * Return: size of DTB header in bytes
276 */
277size_t fdt_header_size(const void *fdt);
278
279/**
280 * fdt_header_size_ - internal function to get header size from a version number
281 * @version: devicetree version number
282 *
283 * Return: size of DTB header in bytes
284 */
285size_t fdt_header_size_(uint32_t version);
286
287/**
288 * fdt_check_header - sanity check a device tree header
289 * @fdt: pointer to data which might be a flattened device tree
290 *
291 * fdt_check_header() checks that the given buffer contains what
292 * appears to be a flattened device tree, and that the header contains
293 * valid information (to the extent that can be determined from the
294 * header alone).
295 *
296 * returns:
297 * 0, if the buffer appears to contain a valid device tree
298 * -FDT_ERR_BADMAGIC,
299 * -FDT_ERR_BADVERSION,
300 * -FDT_ERR_BADSTATE,
301 * -FDT_ERR_TRUNCATED, standard meanings, as above
302 */
303int fdt_check_header(const void *fdt);
304
305/**
306 * fdt_move - move a device tree around in memory
307 * @fdt: pointer to the device tree to move
308 * @buf: pointer to memory where the device is to be moved
309 * @bufsize: size of the memory space at buf
310 *
311 * fdt_move() relocates, if possible, the device tree blob located at
312 * fdt to the buffer at buf of size bufsize. The buffer may overlap
313 * with the existing device tree blob at fdt. Therefore,
314 * fdt_move(fdt, fdt, fdt_totalsize(fdt))
315 * should always succeed.
316 *
317 * returns:
318 * 0, on success
319 * -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
320 * -FDT_ERR_BADMAGIC,
321 * -FDT_ERR_BADVERSION,
322 * -FDT_ERR_BADSTATE, standard meanings
323 */
324int fdt_move(const void *fdt, void *buf, int bufsize);
325
326/**********************************************************************/
327/* Read-only functions */
328/**********************************************************************/
329
330int fdt_check_full(const void *fdt, size_t bufsize);
331
332/**
333 * fdt_get_string - retrieve a string from the strings block of a device tree
334 * @fdt: pointer to the device tree blob
335 * @stroffset: offset of the string within the strings block (native endian)
336 * @lenp: optional pointer to return the string's length
337 *
338 * fdt_get_string() retrieves a pointer to a single string from the
339 * strings block of the device tree blob at fdt, and optionally also
340 * returns the string's length in *lenp.
341 *
342 * returns:
343 * a pointer to the string, on success
344 * NULL, if stroffset is out of bounds, or doesn't point to a valid string
345 */
346const char *fdt_get_string(const void *fdt, int stroffset, int *lenp);
347
348/**
349 * fdt_string - retrieve a string from the strings block of a device tree
350 * @fdt: pointer to the device tree blob
351 * @stroffset: offset of the string within the strings block (native endian)
352 *
353 * fdt_string() retrieves a pointer to a single string from the
354 * strings block of the device tree blob at fdt.
355 *
356 * returns:
357 * a pointer to the string, on success
358 * NULL, if stroffset is out of bounds, or doesn't point to a valid string
359 */
360const char *fdt_string(const void *fdt, int stroffset);
361
362/**
363 * fdt_find_max_phandle - find and return the highest phandle in a tree
364 * @fdt: pointer to the device tree blob
365 * @phandle: return location for the highest phandle value found in the tree
366 *
367 * fdt_find_max_phandle() finds the highest phandle value in the given device
368 * tree. The value returned in @phandle is only valid if the function returns
369 * success.
370 *
371 * returns:
372 * 0 on success or a negative error code on failure
373 */
374int fdt_find_max_phandle(const void *fdt, uint32_t *phandle);
375
376/**
377 * fdt_get_max_phandle - retrieves the highest phandle in a tree
378 * @fdt: pointer to the device tree blob
379 *
380 * fdt_get_max_phandle retrieves the highest phandle in the given
381 * device tree. This will ignore badly formatted phandles, or phandles
382 * with a value of 0 or -1.
383 *
384 * This function is deprecated in favour of fdt_find_max_phandle().
385 *
386 * returns:
387 * the highest phandle on success
388 * 0, if no phandle was found in the device tree
389 * -1, if an error occurred
390 */
391static inline uint32_t fdt_get_max_phandle(const void *fdt)
392{
393 uint32_t phandle;
394 int err;
395
396 err = fdt_find_max_phandle(fdt, &phandle);
397 if (err < 0)
398 return (uint32_t)-1;
399
400 return phandle;
401}
402
403/**
404 * fdt_generate_phandle - return a new, unused phandle for a device tree blob
405 * @fdt: pointer to the device tree blob
406 * @phandle: return location for the new phandle
407 *
408 * Walks the device tree blob and looks for the highest phandle value. On
409 * success, the new, unused phandle value (one higher than the previously
410 * highest phandle value in the device tree blob) will be returned in the
411 * @phandle parameter.
412 *
413 * Return: 0 on success or a negative error-code on failure
414 */
415int fdt_generate_phandle(const void *fdt, uint32_t *phandle);
416
417/**
418 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
419 * @fdt: pointer to the device tree blob
420 *
421 * Returns the number of entries in the device tree blob's memory
422 * reservation map. This does not include the terminating 0,0 entry
423 * or any other (0,0) entries reserved for expansion.
424 *
425 * returns:
426 * the number of entries
427 */
428int fdt_num_mem_rsv(const void *fdt);
429
430/**
431 * fdt_get_mem_rsv - retrieve one memory reserve map entry
432 * @fdt: pointer to the device tree blob
433 * @n: index of reserve map entry
434 * @address: pointer to 64-bit variable to hold the start address
435 * @size: pointer to 64-bit variable to hold the size of the entry
436 *
437 * On success, @address and @size will contain the address and size of
438 * the n-th reserve map entry from the device tree blob, in
439 * native-endian format.
440 *
441 * returns:
442 * 0, on success
443 * -FDT_ERR_BADMAGIC,
444 * -FDT_ERR_BADVERSION,
445 * -FDT_ERR_BADSTATE, standard meanings
446 */
447int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
448
449/**
450 * fdt_subnode_offset_namelen - find a subnode based on substring
451 * @fdt: pointer to the device tree blob
452 * @parentoffset: structure block offset of a node
453 * @name: name of the subnode to locate
454 * @namelen: number of characters of name to consider
455 *
456 * Identical to fdt_subnode_offset(), but only examine the first
457 * namelen characters of name for matching the subnode name. This is
458 * useful for finding subnodes based on a portion of a larger string,
459 * such as a full path.
460 *
461 * Return: offset of the subnode or -FDT_ERR_NOTFOUND if name not found.
462 */
463#ifndef SWIG /* Not available in Python */
464int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
465 const char *name, int namelen);
466#endif
467/**
468 * fdt_subnode_offset - find a subnode of a given node
469 * @fdt: pointer to the device tree blob
470 * @parentoffset: structure block offset of a node
471 * @name: name of the subnode to locate
472 *
473 * fdt_subnode_offset() finds a subnode of the node at structure block
474 * offset parentoffset with the given name. name may include a unit
475 * address, in which case fdt_subnode_offset() will find the subnode
476 * with that unit address, or the unit address may be omitted, in
477 * which case fdt_subnode_offset() will find an arbitrary subnode
478 * whose name excluding unit address matches the given name.
479 *
480 * returns:
481 * structure block offset of the requested subnode (>=0), on success
482 * -FDT_ERR_NOTFOUND, if the requested subnode does not exist
483 * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
484 * tag
485 * -FDT_ERR_BADMAGIC,
486 * -FDT_ERR_BADVERSION,
487 * -FDT_ERR_BADSTATE,
488 * -FDT_ERR_BADSTRUCTURE,
489 * -FDT_ERR_TRUNCATED, standard meanings.
490 */
491int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
492
493/**
494 * fdt_path_offset_namelen - find a tree node by its full path
495 * @fdt: pointer to the device tree blob
496 * @path: full path of the node to locate
497 * @namelen: number of characters of path to consider
498 *
499 * Identical to fdt_path_offset(), but only consider the first namelen
500 * characters of path as the path name.
501 *
502 * Return: offset of the node or negative libfdt error value otherwise
503 */
504#ifndef SWIG /* Not available in Python */
505int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen);
506#endif
507
508/**
509 * fdt_path_offset - find a tree node by its full path
510 * @fdt: pointer to the device tree blob
511 * @path: full path of the node to locate
512 *
513 * fdt_path_offset() finds a node of a given path in the device tree.
514 * Each path component may omit the unit address portion, but the
515 * results of this are undefined if any such path component is
516 * ambiguous (that is if there are multiple nodes at the relevant
517 * level matching the given component, differentiated only by unit
518 * address).
519 *
520 * returns:
521 * structure block offset of the node with the requested path (>=0), on
522 * success
523 * -FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
524 * -FDT_ERR_NOTFOUND, if the requested node does not exist
525 * -FDT_ERR_BADMAGIC,
526 * -FDT_ERR_BADVERSION,
527 * -FDT_ERR_BADSTATE,
528 * -FDT_ERR_BADSTRUCTURE,
529 * -FDT_ERR_TRUNCATED, standard meanings.
530 */
531int fdt_path_offset(const void *fdt, const char *path);
532
533/**
534 * fdt_get_name - retrieve the name of a given node
535 * @fdt: pointer to the device tree blob
536 * @nodeoffset: structure block offset of the starting node
537 * @lenp: pointer to an integer variable (will be overwritten) or NULL
538 *
539 * fdt_get_name() retrieves the name (including unit address) of the
540 * device tree node at structure block offset nodeoffset. If lenp is
541 * non-NULL, the length of this name is also returned, in the integer
542 * pointed to by lenp.
543 *
544 * returns:
545 * pointer to the node's name, on success
546 * If lenp is non-NULL, *lenp contains the length of that name
547 * (>=0)
548 * NULL, on error
549 * if lenp is non-NULL *lenp contains an error code (<0):
550 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
551 * tag
552 * -FDT_ERR_BADMAGIC,
553 * -FDT_ERR_BADVERSION,
554 * -FDT_ERR_BADSTATE, standard meanings
555 */
556const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
557
558/**
559 * fdt_first_property_offset - find the offset of a node's first property
560 * @fdt: pointer to the device tree blob
561 * @nodeoffset: structure block offset of a node
562 *
563 * fdt_first_property_offset() finds the first property of the node at
564 * the given structure block offset.
565 *
566 * returns:
567 * structure block offset of the property (>=0), on success
568 * -FDT_ERR_NOTFOUND, if the requested node has no properties
569 * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
570 * -FDT_ERR_BADMAGIC,
571 * -FDT_ERR_BADVERSION,
572 * -FDT_ERR_BADSTATE,
573 * -FDT_ERR_BADSTRUCTURE,
574 * -FDT_ERR_TRUNCATED, standard meanings.
575 */
576int fdt_first_property_offset(const void *fdt, int nodeoffset);
577
578/**
579 * fdt_next_property_offset - step through a node's properties
580 * @fdt: pointer to the device tree blob
581 * @offset: structure block offset of a property
582 *
583 * fdt_next_property_offset() finds the property immediately after the
584 * one at the given structure block offset. This will be a property
585 * of the same node as the given property.
586 *
587 * returns:
588 * structure block offset of the next property (>=0), on success
589 * -FDT_ERR_NOTFOUND, if the given property is the last in its node
590 * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag
591 * -FDT_ERR_BADMAGIC,
592 * -FDT_ERR_BADVERSION,
593 * -FDT_ERR_BADSTATE,
594 * -FDT_ERR_BADSTRUCTURE,
595 * -FDT_ERR_TRUNCATED, standard meanings.
596 */
597int fdt_next_property_offset(const void *fdt, int offset);
598
599/**
600 * fdt_for_each_property_offset - iterate over all properties of a node
601 *
602 * @property: property offset (int, lvalue)
603 * @fdt: FDT blob (const void *)
604 * @node: node offset (int)
605 *
606 * This is actually a wrapper around a for loop and would be used like so:
607 *
608 * fdt_for_each_property_offset(property, fdt, node) {
609 * Use property
610 * ...
611 * }
612 *
613 * if ((property < 0) && (property != -FDT_ERR_NOTFOUND)) {
614 * Error handling
615 * }
616 *
617 * Note that this is implemented as a macro and property is used as
618 * iterator in the loop. The node variable can be constant or even a
619 * literal.
620 */
621#define fdt_for_each_property_offset(property, fdt, node) \
622 for (property = fdt_first_property_offset(fdt, node); \
623 property >= 0; \
624 property = fdt_next_property_offset(fdt, property))
625
626/**
627 * fdt_get_property_by_offset - retrieve the property at a given offset
628 * @fdt: pointer to the device tree blob
629 * @offset: offset of the property to retrieve
630 * @lenp: pointer to an integer variable (will be overwritten) or NULL
631 *
632 * fdt_get_property_by_offset() retrieves a pointer to the
633 * fdt_property structure within the device tree blob at the given
634 * offset. If lenp is non-NULL, the length of the property value is
635 * also returned, in the integer pointed to by lenp.
636 *
637 * Note that this code only works on device tree versions >= 16. fdt_getprop()
638 * works on all versions.
639 *
640 * returns:
641 * pointer to the structure representing the property
642 * if lenp is non-NULL, *lenp contains the length of the property
643 * value (>=0)
644 * NULL, on error
645 * if lenp is non-NULL, *lenp contains an error code (<0):
646 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
647 * -FDT_ERR_BADMAGIC,
648 * -FDT_ERR_BADVERSION,
649 * -FDT_ERR_BADSTATE,
650 * -FDT_ERR_BADSTRUCTURE,
651 * -FDT_ERR_TRUNCATED, standard meanings
652 */
653const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
654 int offset,
655 int *lenp);
656
657/**
658 * fdt_get_property_namelen - find a property based on substring
659 * @fdt: pointer to the device tree blob
660 * @nodeoffset: offset of the node whose property to find
661 * @name: name of the property to find
662 * @namelen: number of characters of name to consider
663 * @lenp: pointer to an integer variable (will be overwritten) or NULL
664 *
665 * Identical to fdt_get_property(), but only examine the first namelen
666 * characters of name for matching the property name.
667 *
668 * Return: pointer to the structure representing the property, or NULL
669 * if not found
670 */
671#ifndef SWIG /* Not available in Python */
672const struct fdt_property *fdt_get_property_namelen(const void *fdt,
673 int nodeoffset,
674 const char *name,
675 int namelen, int *lenp);
676#endif
677
678/**
679 * fdt_get_property - find a given property in a given node
680 * @fdt: pointer to the device tree blob
681 * @nodeoffset: offset of the node whose property to find
682 * @name: name of the property to find
683 * @lenp: pointer to an integer variable (will be overwritten) or NULL
684 *
685 * fdt_get_property() retrieves a pointer to the fdt_property
686 * structure within the device tree blob corresponding to the property
687 * named 'name' of the node at offset nodeoffset. If lenp is
688 * non-NULL, the length of the property value is also returned, in the
689 * integer pointed to by lenp.
690 *
691 * returns:
692 * pointer to the structure representing the property
693 * if lenp is non-NULL, *lenp contains the length of the property
694 * value (>=0)
695 * NULL, on error
696 * if lenp is non-NULL, *lenp contains an error code (<0):
697 * -FDT_ERR_NOTFOUND, node does not have named property
698 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
699 * tag
700 * -FDT_ERR_BADMAGIC,
701 * -FDT_ERR_BADVERSION,
702 * -FDT_ERR_BADSTATE,
703 * -FDT_ERR_BADSTRUCTURE,
704 * -FDT_ERR_TRUNCATED, standard meanings
705 */
706const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
707 const char *name, int *lenp);
708static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
709 const char *name,
710 int *lenp)
711{
712 return (struct fdt_property *)(uintptr_t)
713 fdt_get_property(fdt, nodeoffset, name, lenp);
714}
715
716/**
717 * fdt_getprop_by_offset - retrieve the value of a property at a given offset
718 * @fdt: pointer to the device tree blob
719 * @offset: offset of the property to read
720 * @namep: pointer to a string variable (will be overwritten) or NULL
721 * @lenp: pointer to an integer variable (will be overwritten) or NULL
722 *
723 * fdt_getprop_by_offset() retrieves a pointer to the value of the
724 * property at structure block offset 'offset' (this will be a pointer
725 * to within the device blob itself, not a copy of the value). If
726 * lenp is non-NULL, the length of the property value is also
727 * returned, in the integer pointed to by lenp. If namep is non-NULL,
728 * the property's namne will also be returned in the char * pointed to
729 * by namep (this will be a pointer to within the device tree's string
730 * block, not a new copy of the name).
731 *
732 * returns:
733 * pointer to the property's value
734 * if lenp is non-NULL, *lenp contains the length of the property
735 * value (>=0)
736 * if namep is non-NULL *namep contiains a pointer to the property
737 * name.
738 * NULL, on error
739 * if lenp is non-NULL, *lenp contains an error code (<0):
740 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
741 * -FDT_ERR_BADMAGIC,
742 * -FDT_ERR_BADVERSION,
743 * -FDT_ERR_BADSTATE,
744 * -FDT_ERR_BADSTRUCTURE,
745 * -FDT_ERR_TRUNCATED, standard meanings
746 */
747#ifndef SWIG /* This function is not useful in Python */
748const void *fdt_getprop_by_offset(const void *fdt, int offset,
749 const char **namep, int *lenp);
750#endif
751
752/**
753 * fdt_getprop_namelen - get property value based on substring
754 * @fdt: pointer to the device tree blob
755 * @nodeoffset: offset of the node whose property to find
756 * @name: name of the property to find
757 * @namelen: number of characters of name to consider
758 * @lenp: pointer to an integer variable (will be overwritten) or NULL
759 *
760 * Identical to fdt_getprop(), but only examine the first namelen
761 * characters of name for matching the property name.
762 *
763 * Return: pointer to the property's value or NULL on error
764 */
765#ifndef SWIG /* Not available in Python */
766const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
767 const char *name, int namelen, int *lenp);
768static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset,
769 const char *name, int namelen,
770 int *lenp)
771{
772 return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name,
773 namelen, lenp);
774}
775#endif
776
777/**
778 * fdt_getprop - retrieve the value of a given property
779 * @fdt: pointer to the device tree blob
780 * @nodeoffset: offset of the node whose property to find
781 * @name: name of the property to find
782 * @lenp: pointer to an integer variable (will be overwritten) or NULL
783 *
784 * fdt_getprop() retrieves a pointer to the value of the property
785 * named @name of the node at offset @nodeoffset (this will be a
786 * pointer to within the device blob itself, not a copy of the value).
787 * If @lenp is non-NULL, the length of the property value is also
788 * returned, in the integer pointed to by @lenp.
789 *
790 * returns:
791 * pointer to the property's value
792 * if lenp is non-NULL, *lenp contains the length of the property
793 * value (>=0)
794 * NULL, on error
795 * if lenp is non-NULL, *lenp contains an error code (<0):
796 * -FDT_ERR_NOTFOUND, node does not have named property
797 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
798 * tag
799 * -FDT_ERR_BADMAGIC,
800 * -FDT_ERR_BADVERSION,
801 * -FDT_ERR_BADSTATE,
802 * -FDT_ERR_BADSTRUCTURE,
803 * -FDT_ERR_TRUNCATED, standard meanings
804 */
805const void *fdt_getprop(const void *fdt, int nodeoffset,
806 const char *name, int *lenp);
807static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
808 const char *name, int *lenp)
809{
810 return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
811}
812
813/**
814 * fdt_get_phandle - retrieve the phandle of a given node
815 * @fdt: pointer to the device tree blob
816 * @nodeoffset: structure block offset of the node
817 *
818 * fdt_get_phandle() retrieves the phandle of the device tree node at
819 * structure block offset nodeoffset.
820 *
821 * returns:
822 * the phandle of the node at nodeoffset, on success (!= 0, != -1)
823 * 0, if the node has no phandle, or another error occurs
824 */
825uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
826
827/**
828 * fdt_get_alias_namelen - get alias based on substring
829 * @fdt: pointer to the device tree blob
830 * @name: name of the alias th look up
831 * @namelen: number of characters of name to consider
832 *
833 * Identical to fdt_get_alias(), but only examine the first @namelen
834 * characters of @name for matching the alias name.
835 *
836 * Return: a pointer to the expansion of the alias named @name, if it exists,
837 * NULL otherwise
838 */
839#ifndef SWIG /* Not available in Python */
840const char *fdt_get_alias_namelen(const void *fdt,
841 const char *name, int namelen);
842#endif
843
844/**
845 * fdt_get_alias - retrieve the path referenced by a given alias
846 * @fdt: pointer to the device tree blob
847 * @name: name of the alias th look up
848 *
849 * fdt_get_alias() retrieves the value of a given alias. That is, the
850 * value of the property named @name in the node /aliases.
851 *
852 * returns:
853 * a pointer to the expansion of the alias named 'name', if it exists
854 * NULL, if the given alias or the /aliases node does not exist
855 */
856const char *fdt_get_alias(const void *fdt, const char *name);
857
858/**
859 * fdt_get_path - determine the full path of a node
860 * @fdt: pointer to the device tree blob
861 * @nodeoffset: offset of the node whose path to find
862 * @buf: character buffer to contain the returned path (will be overwritten)
863 * @buflen: size of the character buffer at buf
864 *
865 * fdt_get_path() computes the full path of the node at offset
866 * nodeoffset, and records that path in the buffer at buf.
867 *
868 * NOTE: This function is expensive, as it must scan the device tree
869 * structure from the start to nodeoffset.
870 *
871 * returns:
872 * 0, on success
873 * buf contains the absolute path of the node at
874 * nodeoffset, as a NUL-terminated string.
875 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
876 * -FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
877 * characters and will not fit in the given buffer.
878 * -FDT_ERR_BADMAGIC,
879 * -FDT_ERR_BADVERSION,
880 * -FDT_ERR_BADSTATE,
881 * -FDT_ERR_BADSTRUCTURE, standard meanings
882 */
883int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
884
885/**
886 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
887 * @fdt: pointer to the device tree blob
888 * @nodeoffset: offset of the node whose parent to find
889 * @supernodedepth: depth of the ancestor to find
890 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
891 *
892 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
893 * at a specific depth from the root (where the root itself has depth
894 * 0, its immediate subnodes depth 1 and so forth). So
895 * fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
896 * will always return 0, the offset of the root node. If the node at
897 * nodeoffset has depth D, then:
898 * fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
899 * will return nodeoffset itself.
900 *
901 * NOTE: This function is expensive, as it must scan the device tree
902 * structure from the start to nodeoffset.
903 *
904 * returns:
905 * structure block offset of the node at node offset's ancestor
906 * of depth supernodedepth (>=0), on success
907 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
908 * -FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of
909 * nodeoffset
910 * -FDT_ERR_BADMAGIC,
911 * -FDT_ERR_BADVERSION,
912 * -FDT_ERR_BADSTATE,
913 * -FDT_ERR_BADSTRUCTURE, standard meanings
914 */
915int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
916 int supernodedepth, int *nodedepth);
917
918/**
919 * fdt_node_depth - find the depth of a given node
920 * @fdt: pointer to the device tree blob
921 * @nodeoffset: offset of the node whose parent to find
922 *
923 * fdt_node_depth() finds the depth of a given node. The root node
924 * has depth 0, its immediate subnodes depth 1 and so forth.
925 *
926 * NOTE: This function is expensive, as it must scan the device tree
927 * structure from the start to nodeoffset.
928 *
929 * returns:
930 * depth of the node at nodeoffset (>=0), on success
931 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
932 * -FDT_ERR_BADMAGIC,
933 * -FDT_ERR_BADVERSION,
934 * -FDT_ERR_BADSTATE,
935 * -FDT_ERR_BADSTRUCTURE, standard meanings
936 */
937int fdt_node_depth(const void *fdt, int nodeoffset);
938
939/**
940 * fdt_parent_offset - find the parent of a given node
941 * @fdt: pointer to the device tree blob
942 * @nodeoffset: offset of the node whose parent to find
943 *
944 * fdt_parent_offset() locates the parent node of a given node (that
945 * is, it finds the offset of the node which contains the node at
946 * nodeoffset as a subnode).
947 *
948 * NOTE: This function is expensive, as it must scan the device tree
949 * structure from the start to nodeoffset, *twice*.
950 *
951 * returns:
952 * structure block offset of the parent of the node at nodeoffset
953 * (>=0), on success
954 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
955 * -FDT_ERR_BADMAGIC,
956 * -FDT_ERR_BADVERSION,
957 * -FDT_ERR_BADSTATE,
958 * -FDT_ERR_BADSTRUCTURE, standard meanings
959 */
960int fdt_parent_offset(const void *fdt, int nodeoffset);
961
962/**
963 * fdt_node_offset_by_prop_value - find nodes with a given property value
964 * @fdt: pointer to the device tree blob
965 * @startoffset: only find nodes after this offset
966 * @propname: property name to check
967 * @propval: property value to search for
968 * @proplen: length of the value in propval
969 *
970 * fdt_node_offset_by_prop_value() returns the offset of the first
971 * node after startoffset, which has a property named propname whose
972 * value is of length proplen and has value equal to propval; or if
973 * startoffset is -1, the very first such node in the tree.
974 *
975 * To iterate through all nodes matching the criterion, the following
976 * idiom can be used:
977 * offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
978 * propval, proplen);
979 * while (offset != -FDT_ERR_NOTFOUND) {
980 * // other code here
981 * offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
982 * propval, proplen);
983 * }
984 *
985 * Note the -1 in the first call to the function, if 0 is used here
986 * instead, the function will never locate the root node, even if it
987 * matches the criterion.
988 *
989 * returns:
990 * structure block offset of the located node (>= 0, >startoffset),
991 * on success
992 * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
993 * tree after startoffset
994 * -FDT_ERR_BADOFFSET, 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_offset_by_prop_value(const void *fdt, int startoffset,
1001 const char *propname,
1002 const void *propval, int proplen);
1003
1004/**
1005 * fdt_node_offset_by_phandle - find the node with a given phandle
1006 * @fdt: pointer to the device tree blob
1007 * @phandle: phandle value
1008 *
1009 * fdt_node_offset_by_phandle() returns the offset of the node
1010 * which has the given phandle value. If there is more than one node
1011 * in the tree with the given phandle (an invalid tree), results are
1012 * undefined.
1013 *
1014 * returns:
1015 * structure block offset of the located node (>= 0), on success
1016 * -FDT_ERR_NOTFOUND, no node with that phandle exists
1017 * -FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
1018 * -FDT_ERR_BADMAGIC,
1019 * -FDT_ERR_BADVERSION,
1020 * -FDT_ERR_BADSTATE,
1021 * -FDT_ERR_BADSTRUCTURE, standard meanings
1022 */
1023int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
1024
1025/**
1026 * fdt_node_check_compatible - check a node's compatible property
1027 * @fdt: pointer to the device tree blob
1028 * @nodeoffset: offset of a tree node
1029 * @compatible: string to match against
1030 *
1031 * fdt_node_check_compatible() returns 0 if the given node contains a
1032 * @compatible property with the given string as one of its elements,
1033 * it returns non-zero otherwise, or on error.
1034 *
1035 * returns:
1036 * 0, if the node has a 'compatible' property listing the given string
1037 * 1, if the node has a 'compatible' property, but it does not list
1038 * the given string
1039 * -FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
1040 * -FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
1041 * -FDT_ERR_BADMAGIC,
1042 * -FDT_ERR_BADVERSION,
1043 * -FDT_ERR_BADSTATE,
1044 * -FDT_ERR_BADSTRUCTURE, standard meanings
1045 */
1046int fdt_node_check_compatible(const void *fdt, int nodeoffset,
1047 const char *compatible);
1048
1049/**
1050 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
1051 * @fdt: pointer to the device tree blob
1052 * @startoffset: only find nodes after this offset
1053 * @compatible: 'compatible' string to match against
1054 *
1055 * fdt_node_offset_by_compatible() returns the offset of the first
1056 * node after startoffset, which has a 'compatible' property which
1057 * lists the given compatible string; or if startoffset is -1, the
1058 * very first such node in the tree.
1059 *
1060 * To iterate through all nodes matching the criterion, the following
1061 * idiom can be used:
1062 * offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
1063 * while (offset != -FDT_ERR_NOTFOUND) {
1064 * // other code here
1065 * offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
1066 * }
1067 *
1068 * Note the -1 in the first call to the function, if 0 is used here
1069 * instead, the function will never locate the root node, even if it
1070 * matches the criterion.
1071 *
1072 * returns:
1073 * structure block offset of the located node (>= 0, >startoffset),
1074 * on success
1075 * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
1076 * tree after startoffset
1077 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1078 * -FDT_ERR_BADMAGIC,
1079 * -FDT_ERR_BADVERSION,
1080 * -FDT_ERR_BADSTATE,
1081 * -FDT_ERR_BADSTRUCTURE, standard meanings
1082 */
1083int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
1084 const char *compatible);
1085
1086/**
1087 * fdt_stringlist_contains - check a string list property for a string
1088 * @strlist: Property containing a list of strings to check
1089 * @listlen: Length of property
1090 * @str: String to search for
1091 *
1092 * This is a utility function provided for convenience. The list contains
1093 * one or more strings, each terminated by \0, as is found in a device tree
1094 * "compatible" property.
1095 *
1096 * Return: 1 if the string is found in the list, 0 not found, or invalid list
1097 */
1098int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
1099
1100/**
1101 * fdt_stringlist_count - count the number of strings in a string list
1102 * @fdt: pointer to the device tree blob
1103 * @nodeoffset: offset of a tree node
1104 * @property: name of the property containing the string list
1105 *
1106 * Return:
1107 * the number of strings in the given property
1108 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1109 * -FDT_ERR_NOTFOUND if the property does not exist
1110 */
1111int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property);
1112
1113/**
1114 * fdt_stringlist_search - find a string in a string list and return its index
1115 * @fdt: pointer to the device tree blob
1116 * @nodeoffset: offset of a tree node
1117 * @property: name of the property containing the string list
1118 * @string: string to look up in the string list
1119 *
1120 * Note that it is possible for this function to succeed on property values
1121 * that are not NUL-terminated. That's because the function will stop after
1122 * finding the first occurrence of @string. This can for example happen with
1123 * small-valued cell properties, such as #address-cells, when searching for
1124 * the empty string.
1125 *
1126 * return:
1127 * the index of the string in the list of strings
1128 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1129 * -FDT_ERR_NOTFOUND if the property does not exist or does not contain
1130 * the given string
1131 */
1132int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
1133 const char *string);
1134
1135/**
1136 * fdt_stringlist_get() - obtain the string at a given index in a string list
1137 * @fdt: pointer to the device tree blob
1138 * @nodeoffset: offset of a tree node
1139 * @property: name of the property containing the string list
1140 * @index: index of the string to return
1141 * @lenp: return location for the string length or an error code on failure
1142 *
1143 * Note that this will successfully extract strings from properties with
1144 * non-NUL-terminated values. For example on small-valued cell properties
1145 * this function will return the empty string.
1146 *
1147 * If non-NULL, the length of the string (on success) or a negative error-code
1148 * (on failure) will be stored in the integer pointer to by lenp.
1149 *
1150 * Return:
1151 * A pointer to the string at the given index in the string list or NULL on
1152 * failure. On success the length of the string will be stored in the memory
1153 * location pointed to by the lenp parameter, if non-NULL. On failure one of
1154 * the following negative error codes will be returned in the lenp parameter
1155 * (if non-NULL):
1156 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1157 * -FDT_ERR_NOTFOUND if the property does not exist
1158 */
1159const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
1160 const char *property, int index,
1161 int *lenp);
1162
1163/**********************************************************************/
1164/* Read-only functions (addressing related) */
1165/**********************************************************************/
1166
1167/**
1168 * FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells
1169 *
1170 * This is the maximum value for #address-cells, #size-cells and
1171 * similar properties that will be processed by libfdt. IEE1275
1172 * requires that OF implementations handle values up to 4.
1173 * Implementations may support larger values, but in practice higher
1174 * values aren't used.
1175 */
1176#define FDT_MAX_NCELLS 4
1177
1178/**
1179 * fdt_address_cells - retrieve address size for a bus represented in the tree
1180 * @fdt: pointer to the device tree blob
1181 * @nodeoffset: offset of the node to find the address size for
1182 *
1183 * When the node has a valid #address-cells property, returns its value.
1184 *
1185 * returns:
1186 * 0 <= n < FDT_MAX_NCELLS, on success
1187 * 2, if the node has no #address-cells property
1188 * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1189 * #address-cells property
1190 * -FDT_ERR_BADMAGIC,
1191 * -FDT_ERR_BADVERSION,
1192 * -FDT_ERR_BADSTATE,
1193 * -FDT_ERR_BADSTRUCTURE,
1194 * -FDT_ERR_TRUNCATED, standard meanings
1195 */
1196int fdt_address_cells(const void *fdt, int nodeoffset);
1197
1198/**
1199 * fdt_size_cells - retrieve address range size for a bus represented in the
1200 * tree
1201 * @fdt: pointer to the device tree blob
1202 * @nodeoffset: offset of the node to find the address range size for
1203 *
1204 * When the node has a valid #size-cells property, returns its value.
1205 *
1206 * returns:
1207 * 0 <= n < FDT_MAX_NCELLS, on success
1208 * 1, if the node has no #size-cells property
1209 * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1210 * #size-cells property
1211 * -FDT_ERR_BADMAGIC,
1212 * -FDT_ERR_BADVERSION,
1213 * -FDT_ERR_BADSTATE,
1214 * -FDT_ERR_BADSTRUCTURE,
1215 * -FDT_ERR_TRUNCATED, standard meanings
1216 */
1217int fdt_size_cells(const void *fdt, int nodeoffset);
1218
1219
1220/**********************************************************************/
1221/* Write-in-place functions */
1222/**********************************************************************/
1223
1224/**
1225 * fdt_setprop_inplace_namelen_partial - change a property's value,
1226 * but not its size
1227 * @fdt: pointer to the device tree blob
1228 * @nodeoffset: offset of the node whose property to change
1229 * @name: name of the property to change
1230 * @namelen: number of characters of name to consider
1231 * @idx: index of the property to change in the array
1232 * @val: pointer to data to replace the property value with
1233 * @len: length of the property value
1234 *
1235 * Identical to fdt_setprop_inplace(), but modifies the given property
1236 * starting from the given index, and using only the first characters
1237 * of the name. It is useful when you want to manipulate only one value of
1238 * an array and you have a string that doesn't end with \0.
1239 *
1240 * Return: 0 on success, negative libfdt error value otherwise
1241 */
1242#ifndef SWIG /* Not available in Python */
1243int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
1244 const char *name, int namelen,
1245 uint32_t idx, const void *val,
1246 int len);
1247#endif
1248
1249/**
1250 * fdt_setprop_inplace - change a property's value, but not its size
1251 * @fdt: pointer to the device tree blob
1252 * @nodeoffset: offset of the node whose property to change
1253 * @name: name of the property to change
1254 * @val: pointer to data to replace the property value with
1255 * @len: length of the property value
1256 *
1257 * fdt_setprop_inplace() replaces the value of a given property with
1258 * the data in val, of length len. This function cannot change the
1259 * size of a property, and so will only work if len is equal to the
1260 * current length of the property.
1261 *
1262 * This function will alter only the bytes in the blob which contain
1263 * the given property value, and will not alter or move any other part
1264 * of the tree.
1265 *
1266 * returns:
1267 * 0, on success
1268 * -FDT_ERR_NOSPACE, if len is not equal to the property's current length
1269 * -FDT_ERR_NOTFOUND, node does not have the named property
1270 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1271 * -FDT_ERR_BADMAGIC,
1272 * -FDT_ERR_BADVERSION,
1273 * -FDT_ERR_BADSTATE,
1274 * -FDT_ERR_BADSTRUCTURE,
1275 * -FDT_ERR_TRUNCATED, standard meanings
1276 */
1277#ifndef SWIG /* Not available in Python */
1278int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
1279 const void *val, int len);
1280#endif
1281
1282/**
1283 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
1284 * @fdt: pointer to the device tree blob
1285 * @nodeoffset: offset of the node whose property to change
1286 * @name: name of the property to change
1287 * @val: 32-bit integer value to replace the property with
1288 *
1289 * fdt_setprop_inplace_u32() replaces the value of a given property
1290 * with the 32-bit integer value in val, converting val to big-endian
1291 * if necessary. This function cannot change the size of a property,
1292 * and so will only work if the property already exists and has length
1293 * 4.
1294 *
1295 * This function will alter only the bytes in the blob which contain
1296 * the given property value, and will not alter or move any other part
1297 * of the tree.
1298 *
1299 * returns:
1300 * 0, on success
1301 * -FDT_ERR_NOSPACE, if the property's length is not equal to 4
1302 * -FDT_ERR_NOTFOUND, node does not have the named property
1303 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1304 * -FDT_ERR_BADMAGIC,
1305 * -FDT_ERR_BADVERSION,
1306 * -FDT_ERR_BADSTATE,
1307 * -FDT_ERR_BADSTRUCTURE,
1308 * -FDT_ERR_TRUNCATED, standard meanings
1309 */
1310static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
1311 const char *name, uint32_t val)
1312{
1313 fdt32_t tmp = cpu_to_fdt32(val);
1314 return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1315}
1316
1317/**
1318 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
1319 * @fdt: pointer to the device tree blob
1320 * @nodeoffset: offset of the node whose property to change
1321 * @name: name of the property to change
1322 * @val: 64-bit integer value to replace the property with
1323 *
1324 * fdt_setprop_inplace_u64() replaces the value of a given property
1325 * with the 64-bit integer value in val, converting val to big-endian
1326 * if necessary. This function cannot change the size of a property,
1327 * and so will only work if the property already exists and has length
1328 * 8.
1329 *
1330 * This function will alter only the bytes in the blob which contain
1331 * the given property value, and will not alter or move any other part
1332 * of the tree.
1333 *
1334 * returns:
1335 * 0, on success
1336 * -FDT_ERR_NOSPACE, if the property's length is not equal to 8
1337 * -FDT_ERR_NOTFOUND, node does not have the named property
1338 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1339 * -FDT_ERR_BADMAGIC,
1340 * -FDT_ERR_BADVERSION,
1341 * -FDT_ERR_BADSTATE,
1342 * -FDT_ERR_BADSTRUCTURE,
1343 * -FDT_ERR_TRUNCATED, standard meanings
1344 */
1345static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
1346 const char *name, uint64_t val)
1347{
1348 fdt64_t tmp = cpu_to_fdt64(val);
1349 return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1350}
1351
1352/**
1353 * fdt_setprop_inplace_cell - change the value of a single-cell property
1354 * @fdt: pointer to the device tree blob
1355 * @nodeoffset: offset of the node containing the property
1356 * @name: name of the property to change the value of
1357 * @val: new value of the 32-bit cell
1358 *
1359 * This is an alternative name for fdt_setprop_inplace_u32()
1360 * Return: 0 on success, negative libfdt error number otherwise.
1361 */
1362static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
1363 const char *name, uint32_t val)
1364{
1365 return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
1366}
1367
1368/**
1369 * fdt_nop_property - replace a property with nop tags
1370 * @fdt: pointer to the device tree blob
1371 * @nodeoffset: offset of the node whose property to nop
1372 * @name: name of the property to nop
1373 *
1374 * fdt_nop_property() will replace a given property's representation
1375 * in the blob with FDT_NOP tags, effectively removing it from the
1376 * tree.
1377 *
1378 * This function will alter only the bytes in the blob which contain
1379 * the property, and will not alter or move any other part of the
1380 * tree.
1381 *
1382 * returns:
1383 * 0, on success
1384 * -FDT_ERR_NOTFOUND, node does not have the named property
1385 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1386 * -FDT_ERR_BADMAGIC,
1387 * -FDT_ERR_BADVERSION,
1388 * -FDT_ERR_BADSTATE,
1389 * -FDT_ERR_BADSTRUCTURE,
1390 * -FDT_ERR_TRUNCATED, standard meanings
1391 */
1392int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
1393
1394/**
1395 * fdt_nop_node - replace a node (subtree) with nop tags
1396 * @fdt: pointer to the device tree blob
1397 * @nodeoffset: offset of the node to nop
1398 *
1399 * fdt_nop_node() will replace a given node's representation in the
1400 * blob, including all its subnodes, if any, with FDT_NOP tags,
1401 * effectively removing it from the tree.
1402 *
1403 * This function will alter only the bytes in the blob which contain
1404 * the node and its properties and subnodes, and will not alter or
1405 * move any other part of the tree.
1406 *
1407 * returns:
1408 * 0, on success
1409 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1410 * -FDT_ERR_BADMAGIC,
1411 * -FDT_ERR_BADVERSION,
1412 * -FDT_ERR_BADSTATE,
1413 * -FDT_ERR_BADSTRUCTURE,
1414 * -FDT_ERR_TRUNCATED, standard meanings
1415 */
1416int fdt_nop_node(void *fdt, int nodeoffset);
1417
1418/**********************************************************************/
1419/* Sequential write functions */
1420/**********************************************************************/
1421
1422/* fdt_create_with_flags flags */
1423#define FDT_CREATE_FLAG_NO_NAME_DEDUP 0x1
1424 /* FDT_CREATE_FLAG_NO_NAME_DEDUP: Do not try to de-duplicate property
1425 * names in the fdt. This can result in faster creation times, but
1426 * a larger fdt. */
1427
1428#define FDT_CREATE_FLAGS_ALL (FDT_CREATE_FLAG_NO_NAME_DEDUP)
1429
1430/**
1431 * fdt_create_with_flags - begin creation of a new fdt
1432 * @buf: pointer to memory allocated where fdt will be created
1433 * @bufsize: size of the memory space at fdt
1434 * @flags: a valid combination of FDT_CREATE_FLAG_ flags, or 0.
1435 *
1436 * fdt_create_with_flags() begins the process of creating a new fdt with
1437 * the sequential write interface.
1438 *
1439 * fdt creation process must end with fdt_finished() to produce a valid fdt.
1440 *
1441 * returns:
1442 * 0, on success
1443 * -FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1444 * -FDT_ERR_BADFLAGS, flags is not valid
1445 */
1446int fdt_create_with_flags(void *buf, int bufsize, uint32_t flags);
1447
1448/**
1449 * fdt_create - begin creation of a new fdt
1450 * @buf: pointer to memory allocated where fdt will be created
1451 * @bufsize: size of the memory space at fdt
1452 *
1453 * fdt_create() is equivalent to fdt_create_with_flags() with flags=0.
1454 *
1455 * returns:
1456 * 0, on success
1457 * -FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1458 */
1459int fdt_create(void *buf, int bufsize);
1460
1461int fdt_resize(void *fdt, void *buf, int bufsize);
1462int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
1463int fdt_finish_reservemap(void *fdt);
1464int fdt_begin_node(void *fdt, const char *name);
1465int fdt_property(void *fdt, const char *name, const void *val, int len);
1466static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
1467{
1468 fdt32_t tmp = cpu_to_fdt32(val);
1469 return fdt_property(fdt, name, &tmp, sizeof(tmp));
1470}
1471static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
1472{
1473 fdt64_t tmp = cpu_to_fdt64(val);
1474 return fdt_property(fdt, name, &tmp, sizeof(tmp));
1475}
1476
1477#ifndef SWIG /* Not available in Python */
1478static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
1479{
1480 return fdt_property_u32(fdt, name, val);
1481}
1482#endif
1483
1484/**
1485 * fdt_property_placeholder - add a new property and return a ptr to its value
1486 *
1487 * @fdt: pointer to the device tree blob
1488 * @name: name of property to add
1489 * @len: length of property value in bytes
1490 * @valp: returns a pointer to where where the value should be placed
1491 *
1492 * returns:
1493 * 0, on success
1494 * -FDT_ERR_BADMAGIC,
1495 * -FDT_ERR_NOSPACE, standard meanings
1496 */
1497int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp);
1498
1499#define fdt_property_string(fdt, name, str) \
1500 fdt_property(fdt, name, str, strlen(str)+1)
1501int fdt_end_node(void *fdt);
1502int fdt_finish(void *fdt);
1503
1504/**********************************************************************/
1505/* Read-write functions */
1506/**********************************************************************/
1507
1508int fdt_create_empty_tree(void *buf, int bufsize);
1509int fdt_open_into(const void *fdt, void *buf, int bufsize);
1510int fdt_pack(void *fdt);
1511
1512/**
1513 * fdt_add_mem_rsv - add one memory reserve map entry
1514 * @fdt: pointer to the device tree blob
1515 * @address: 64-bit start address of the reserve map entry
1516 * @size: 64-bit size of the reserved region
1517 *
1518 * Adds a reserve map entry to the given blob reserving a region at
1519 * address address of length size.
1520 *
1521 * This function will insert data into the reserve map and will
1522 * therefore change the indexes of some entries in the table.
1523 *
1524 * returns:
1525 * 0, on success
1526 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1527 * contain the new reservation entry
1528 * -FDT_ERR_BADMAGIC,
1529 * -FDT_ERR_BADVERSION,
1530 * -FDT_ERR_BADSTATE,
1531 * -FDT_ERR_BADSTRUCTURE,
1532 * -FDT_ERR_BADLAYOUT,
1533 * -FDT_ERR_TRUNCATED, standard meanings
1534 */
1535int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
1536
1537/**
1538 * fdt_del_mem_rsv - remove a memory reserve map entry
1539 * @fdt: pointer to the device tree blob
1540 * @n: entry to remove
1541 *
1542 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
1543 * the blob.
1544 *
1545 * This function will delete data from the reservation table and will
1546 * therefore change the indexes of some entries in the table.
1547 *
1548 * returns:
1549 * 0, on success
1550 * -FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
1551 * are less than n+1 reserve map entries)
1552 * -FDT_ERR_BADMAGIC,
1553 * -FDT_ERR_BADVERSION,
1554 * -FDT_ERR_BADSTATE,
1555 * -FDT_ERR_BADSTRUCTURE,
1556 * -FDT_ERR_BADLAYOUT,
1557 * -FDT_ERR_TRUNCATED, standard meanings
1558 */
1559int fdt_del_mem_rsv(void *fdt, int n);
1560
1561/**
1562 * fdt_set_name - change the name of a given node
1563 * @fdt: pointer to the device tree blob
1564 * @nodeoffset: structure block offset of a node
1565 * @name: name to give the node
1566 *
1567 * fdt_set_name() replaces the name (including unit address, if any)
1568 * of the given node with the given string. NOTE: this function can't
1569 * efficiently check if the new name is unique amongst the given
1570 * node's siblings; results are undefined if this function is invoked
1571 * with a name equal to one of the given node's siblings.
1572 *
1573 * This function may insert or delete data from the blob, and will
1574 * therefore change the offsets of some existing nodes.
1575 *
1576 * returns:
1577 * 0, on success
1578 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob
1579 * to contain the new name
1580 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1581 * -FDT_ERR_BADMAGIC,
1582 * -FDT_ERR_BADVERSION,
1583 * -FDT_ERR_BADSTATE, standard meanings
1584 */
1585int fdt_set_name(void *fdt, int nodeoffset, const char *name);
1586
1587/**
1588 * fdt_setprop - create or change a property
1589 * @fdt: pointer to the device tree blob
1590 * @nodeoffset: offset of the node whose property to change
1591 * @name: name of the property to change
1592 * @val: pointer to data to set the property value to
1593 * @len: length of the property value
1594 *
1595 * fdt_setprop() sets the value of the named property in the given
1596 * node to the given value and length, creating the property if it
1597 * does not already exist.
1598 *
1599 * This function may insert or delete data from the blob, and will
1600 * therefore change the offsets of some existing nodes.
1601 *
1602 * returns:
1603 * 0, on success
1604 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1605 * contain the new property value
1606 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1607 * -FDT_ERR_BADLAYOUT,
1608 * -FDT_ERR_BADMAGIC,
1609 * -FDT_ERR_BADVERSION,
1610 * -FDT_ERR_BADSTATE,
1611 * -FDT_ERR_BADSTRUCTURE,
1612 * -FDT_ERR_BADLAYOUT,
1613 * -FDT_ERR_TRUNCATED, standard meanings
1614 */
1615int fdt_setprop(void *fdt, int nodeoffset, const char *name,
1616 const void *val, int len);
1617
1618/**
1619 * fdt_setprop_placeholder - allocate space for a property
1620 * @fdt: pointer to the device tree blob
1621 * @nodeoffset: offset of the node whose property to change
1622 * @name: name of the property to change
1623 * @len: length of the property value
1624 * @prop_data: return pointer to property data
1625 *
1626 * fdt_setprop_placeholer() allocates the named property in the given node.
1627 * If the property exists it is resized. In either case a pointer to the
1628 * property data is returned.
1629 *
1630 * This function may insert or delete data from the blob, and will
1631 * therefore change the offsets of some existing nodes.
1632 *
1633 * returns:
1634 * 0, on success
1635 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1636 * contain the new property value
1637 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1638 * -FDT_ERR_BADLAYOUT,
1639 * -FDT_ERR_BADMAGIC,
1640 * -FDT_ERR_BADVERSION,
1641 * -FDT_ERR_BADSTATE,
1642 * -FDT_ERR_BADSTRUCTURE,
1643 * -FDT_ERR_BADLAYOUT,
1644 * -FDT_ERR_TRUNCATED, standard meanings
1645 */
1646int fdt_setprop_placeholder(void *fdt, int nodeoffset, const char *name,
1647 int len, void **prop_data);
1648
1649/**
1650 * fdt_setprop_u32 - set a property to a 32-bit integer
1651 * @fdt: pointer to the device tree blob
1652 * @nodeoffset: offset of the node whose property to change
1653 * @name: name of the property to change
1654 * @val: 32-bit integer value for the property (native endian)
1655 *
1656 * fdt_setprop_u32() sets the value of the named property in the given
1657 * node to the given 32-bit integer value (converting to big-endian if
1658 * necessary), or creates a new property with that value if it does
1659 * not already exist.
1660 *
1661 * This function may insert or delete data from the blob, and will
1662 * therefore change the offsets of some existing nodes.
1663 *
1664 * returns:
1665 * 0, on success
1666 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1667 * contain the new property value
1668 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1669 * -FDT_ERR_BADLAYOUT,
1670 * -FDT_ERR_BADMAGIC,
1671 * -FDT_ERR_BADVERSION,
1672 * -FDT_ERR_BADSTATE,
1673 * -FDT_ERR_BADSTRUCTURE,
1674 * -FDT_ERR_BADLAYOUT,
1675 * -FDT_ERR_TRUNCATED, standard meanings
1676 */
1677static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
1678 uint32_t val)
1679{
1680 fdt32_t tmp = cpu_to_fdt32(val);
1681 return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1682}
1683
1684/**
1685 * fdt_setprop_u64 - set a property to a 64-bit integer
1686 * @fdt: pointer to the device tree blob
1687 * @nodeoffset: offset of the node whose property to change
1688 * @name: name of the property to change
1689 * @val: 64-bit integer value for the property (native endian)
1690 *
1691 * fdt_setprop_u64() sets the value of the named property in the given
1692 * node to the given 64-bit integer value (converting to big-endian if
1693 * necessary), or creates a new property with that value if it does
1694 * not already exist.
1695 *
1696 * This function may insert or delete data from the blob, and will
1697 * therefore change the offsets of some existing nodes.
1698 *
1699 * returns:
1700 * 0, on success
1701 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1702 * contain the new property value
1703 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1704 * -FDT_ERR_BADLAYOUT,
1705 * -FDT_ERR_BADMAGIC,
1706 * -FDT_ERR_BADVERSION,
1707 * -FDT_ERR_BADSTATE,
1708 * -FDT_ERR_BADSTRUCTURE,
1709 * -FDT_ERR_BADLAYOUT,
1710 * -FDT_ERR_TRUNCATED, standard meanings
1711 */
1712static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
1713 uint64_t val)
1714{
1715 fdt64_t tmp = cpu_to_fdt64(val);
1716 return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1717}
1718
1719/**
1720 * fdt_setprop_cell - set a property to a single cell value
1721 * @fdt: pointer to the device tree blob
1722 * @nodeoffset: offset of the node whose property to change
1723 * @name: name of the property to change
1724 * @val: 32-bit integer value for the property (native endian)
1725 *
1726 * This is an alternative name for fdt_setprop_u32()
1727 *
1728 * Return: 0 on success, negative libfdt error value otherwise.
1729 */
1730static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
1731 uint32_t val)
1732{
1733 return fdt_setprop_u32(fdt, nodeoffset, name, val);
1734}
1735
1736/**
1737 * fdt_setprop_string - set a property to a string value
1738 * @fdt: pointer to the device tree blob
1739 * @nodeoffset: offset of the node whose property to change
1740 * @name: name of the property to change
1741 * @str: string value for the property
1742 *
1743 * fdt_setprop_string() sets the value of the named property in the
1744 * given node to the given string value (using the length of the
1745 * string to determine the new length of the property), or creates a
1746 * new property with that value if it does not already exist.
1747 *
1748 * This function may insert or delete data from the blob, and will
1749 * therefore change the offsets of some existing nodes.
1750 *
1751 * returns:
1752 * 0, on success
1753 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1754 * contain the new property value
1755 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1756 * -FDT_ERR_BADLAYOUT,
1757 * -FDT_ERR_BADMAGIC,
1758 * -FDT_ERR_BADVERSION,
1759 * -FDT_ERR_BADSTATE,
1760 * -FDT_ERR_BADSTRUCTURE,
1761 * -FDT_ERR_BADLAYOUT,
1762 * -FDT_ERR_TRUNCATED, standard meanings
1763 */
1764#define fdt_setprop_string(fdt, nodeoffset, name, str) \
1765 fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1766
1767
1768/**
1769 * fdt_setprop_empty - set a property to an empty value
1770 * @fdt: pointer to the device tree blob
1771 * @nodeoffset: offset of the node whose property to change
1772 * @name: name of the property to change
1773 *
1774 * fdt_setprop_empty() sets the value of the named property in the
1775 * given node to an empty (zero length) value, or creates a new empty
1776 * property if it does not already exist.
1777 *
1778 * This function may insert or delete data from the blob, and will
1779 * therefore change the offsets of some existing nodes.
1780 *
1781 * returns:
1782 * 0, on success
1783 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1784 * contain the new property value
1785 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1786 * -FDT_ERR_BADLAYOUT,
1787 * -FDT_ERR_BADMAGIC,
1788 * -FDT_ERR_BADVERSION,
1789 * -FDT_ERR_BADSTATE,
1790 * -FDT_ERR_BADSTRUCTURE,
1791 * -FDT_ERR_BADLAYOUT,
1792 * -FDT_ERR_TRUNCATED, standard meanings
1793 */
1794#define fdt_setprop_empty(fdt, nodeoffset, name) \
1795 fdt_setprop((fdt), (nodeoffset), (name), NULL, 0)
1796
1797/**
1798 * fdt_appendprop - append to or create a property
1799 * @fdt: pointer to the device tree blob
1800 * @nodeoffset: offset of the node whose property to change
1801 * @name: name of the property to append to
1802 * @val: pointer to data to append to the property value
1803 * @len: length of the data to append to the property value
1804 *
1805 * fdt_appendprop() appends the value to the named property in the
1806 * given node, creating the property if it does not already exist.
1807 *
1808 * This function may insert data into the blob, and will therefore
1809 * change the offsets of some existing nodes.
1810 *
1811 * returns:
1812 * 0, on success
1813 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1814 * contain the new property value
1815 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1816 * -FDT_ERR_BADLAYOUT,
1817 * -FDT_ERR_BADMAGIC,
1818 * -FDT_ERR_BADVERSION,
1819 * -FDT_ERR_BADSTATE,
1820 * -FDT_ERR_BADSTRUCTURE,
1821 * -FDT_ERR_BADLAYOUT,
1822 * -FDT_ERR_TRUNCATED, standard meanings
1823 */
1824int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
1825 const void *val, int len);
1826
1827/**
1828 * fdt_appendprop_u32 - append a 32-bit integer value to a property
1829 * @fdt: pointer to the device tree blob
1830 * @nodeoffset: offset of the node whose property to change
1831 * @name: name of the property to change
1832 * @val: 32-bit integer value to append to the property (native endian)
1833 *
1834 * fdt_appendprop_u32() appends the given 32-bit integer value
1835 * (converting to big-endian if necessary) to the value of the named
1836 * property in the given node, or creates a new property with that
1837 * value if it does not already exist.
1838 *
1839 * This function may insert data into the blob, and will therefore
1840 * change the offsets of some existing nodes.
1841 *
1842 * returns:
1843 * 0, on success
1844 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1845 * contain the new property value
1846 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1847 * -FDT_ERR_BADLAYOUT,
1848 * -FDT_ERR_BADMAGIC,
1849 * -FDT_ERR_BADVERSION,
1850 * -FDT_ERR_BADSTATE,
1851 * -FDT_ERR_BADSTRUCTURE,
1852 * -FDT_ERR_BADLAYOUT,
1853 * -FDT_ERR_TRUNCATED, standard meanings
1854 */
1855static inline int fdt_appendprop_u32(void *fdt, int nodeoffset,
1856 const char *name, uint32_t val)
1857{
1858 fdt32_t tmp = cpu_to_fdt32(val);
1859 return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1860}
1861
1862/**
1863 * fdt_appendprop_u64 - append a 64-bit integer value to a property
1864 * @fdt: pointer to the device tree blob
1865 * @nodeoffset: offset of the node whose property to change
1866 * @name: name of the property to change
1867 * @val: 64-bit integer value to append to the property (native endian)
1868 *
1869 * fdt_appendprop_u64() appends the given 64-bit integer value
1870 * (converting to big-endian if necessary) to the value of the named
1871 * property in the given node, or creates a new property with that
1872 * value if it does not already exist.
1873 *
1874 * This function may insert data into the blob, and will therefore
1875 * change the offsets of some existing nodes.
1876 *
1877 * returns:
1878 * 0, on success
1879 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1880 * contain the new property value
1881 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1882 * -FDT_ERR_BADLAYOUT,
1883 * -FDT_ERR_BADMAGIC,
1884 * -FDT_ERR_BADVERSION,
1885 * -FDT_ERR_BADSTATE,
1886 * -FDT_ERR_BADSTRUCTURE,
1887 * -FDT_ERR_BADLAYOUT,
1888 * -FDT_ERR_TRUNCATED, standard meanings
1889 */
1890static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
1891 const char *name, uint64_t val)
1892{
1893 fdt64_t tmp = cpu_to_fdt64(val);
1894 return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1895}
1896
1897/**
1898 * fdt_appendprop_cell - append a single cell value to a property
1899 * @fdt: pointer to the device tree blob
1900 * @nodeoffset: offset of the node whose property to change
1901 * @name: name of the property to change
1902 * @val: 32-bit integer value to append to the property (native endian)
1903 *
1904 * This is an alternative name for fdt_appendprop_u32()
1905 *
1906 * Return: 0 on success, negative libfdt error value otherwise.
1907 */
1908static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
1909 const char *name, uint32_t val)
1910{
1911 return fdt_appendprop_u32(fdt, nodeoffset, name, val);
1912}
1913
1914/**
1915 * fdt_appendprop_string - append a string to a property
1916 * @fdt: pointer to the device tree blob
1917 * @nodeoffset: offset of the node whose property to change
1918 * @name: name of the property to change
1919 * @str: string value to append to the property
1920 *
1921 * fdt_appendprop_string() appends the given string to the value of
1922 * the named property in the given node, or creates a new property
1923 * with that value if it does not already exist.
1924 *
1925 * This function may insert data into the blob, and will therefore
1926 * change the offsets of some existing nodes.
1927 *
1928 * returns:
1929 * 0, on success
1930 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1931 * contain the new property value
1932 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1933 * -FDT_ERR_BADLAYOUT,
1934 * -FDT_ERR_BADMAGIC,
1935 * -FDT_ERR_BADVERSION,
1936 * -FDT_ERR_BADSTATE,
1937 * -FDT_ERR_BADSTRUCTURE,
1938 * -FDT_ERR_BADLAYOUT,
1939 * -FDT_ERR_TRUNCATED, standard meanings
1940 */
1941#define fdt_appendprop_string(fdt, nodeoffset, name, str) \
1942 fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1943
1944/**
1945 * fdt_appendprop_addrrange - append a address range property
1946 * @fdt: pointer to the device tree blob
1947 * @parent: offset of the parent node
1948 * @nodeoffset: offset of the node to add a property at
1949 * @name: name of property
1950 * @addr: start address of a given range
1951 * @size: size of a given range
1952 *
1953 * fdt_appendprop_addrrange() appends an address range value (start
1954 * address and size) to the value of the named property in the given
1955 * node, or creates a new property with that value if it does not
1956 * already exist.
1957 * If "name" is not specified, a default "reg" is used.
1958 * Cell sizes are determined by parent's #address-cells and #size-cells.
1959 *
1960 * This function may insert data into the blob, and will therefore
1961 * change the offsets of some existing nodes.
1962 *
1963 * returns:
1964 * 0, on success
1965 * -FDT_ERR_BADLAYOUT,
1966 * -FDT_ERR_BADMAGIC,
1967 * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1968 * #address-cells property
1969 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1970 * -FDT_ERR_BADSTATE,
1971 * -FDT_ERR_BADSTRUCTURE,
1972 * -FDT_ERR_BADVERSION,
1973 * -FDT_ERR_BADVALUE, addr or size doesn't fit to respective cells size
1974 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1975 * contain a new property
1976 * -FDT_ERR_TRUNCATED, standard meanings
1977 */
1978int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
1979 const char *name, uint64_t addr, uint64_t size);
1980
1981/**
1982 * fdt_delprop - delete a property
1983 * @fdt: pointer to the device tree blob
1984 * @nodeoffset: offset of the node whose property to nop
1985 * @name: name of the property to nop
1986 *
1987 * fdt_del_property() will delete the given property.
1988 *
1989 * This function will delete data from the blob, and will therefore
1990 * change the offsets of some existing nodes.
1991 *
1992 * returns:
1993 * 0, on success
1994 * -FDT_ERR_NOTFOUND, node does not have the named property
1995 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1996 * -FDT_ERR_BADLAYOUT,
1997 * -FDT_ERR_BADMAGIC,
1998 * -FDT_ERR_BADVERSION,
1999 * -FDT_ERR_BADSTATE,
2000 * -FDT_ERR_BADSTRUCTURE,
2001 * -FDT_ERR_TRUNCATED, standard meanings
2002 */
2003int fdt_delprop(void *fdt, int nodeoffset, const char *name);
2004
2005/**
2006 * fdt_add_subnode_namelen - creates a new node based on substring
2007 * @fdt: pointer to the device tree blob
2008 * @parentoffset: structure block offset of a node
2009 * @name: name of the subnode to create
2010 * @namelen: number of characters of name to consider
2011 *
2012 * Identical to fdt_add_subnode(), but use only the first @namelen
2013 * characters of @name as the name of the new node. This is useful for
2014 * creating subnodes based on a portion of a larger string, such as a
2015 * full path.
2016 *
2017 * Return: structure block offset of the created subnode (>=0),
2018 * negative libfdt error value otherwise
2019 */
2020#ifndef SWIG /* Not available in Python */
2021int fdt_add_subnode_namelen(void *fdt, int parentoffset,
2022 const char *name, int namelen);
2023#endif
2024
2025/**
2026 * fdt_add_subnode - creates a new node
2027 * @fdt: pointer to the device tree blob
2028 * @parentoffset: structure block offset of a node
2029 * @name: name of the subnode to locate
2030 *
2031 * fdt_add_subnode() creates a new node as a subnode of the node at
2032 * structure block offset parentoffset, with the given name (which
2033 * should include the unit address, if any).
2034 *
2035 * This function will insert data into the blob, and will therefore
2036 * change the offsets of some existing nodes.
2037 *
2038 * returns:
2039 * structure block offset of the created nodeequested subnode (>=0), on
2040 * success
2041 * -FDT_ERR_NOTFOUND, if the requested subnode does not exist
2042 * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
2043 * tag
2044 * -FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
2045 * the given name
2046 * -FDT_ERR_NOSPACE, if there is insufficient free space in the
2047 * blob to contain the new node
2048 * -FDT_ERR_NOSPACE
2049 * -FDT_ERR_BADLAYOUT
2050 * -FDT_ERR_BADMAGIC,
2051 * -FDT_ERR_BADVERSION,
2052 * -FDT_ERR_BADSTATE,
2053 * -FDT_ERR_BADSTRUCTURE,
2054 * -FDT_ERR_TRUNCATED, standard meanings.
2055 */
2056int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
2057
2058/**
2059 * fdt_del_node - delete a node (subtree)
2060 * @fdt: pointer to the device tree blob
2061 * @nodeoffset: offset of the node to nop
2062 *
2063 * fdt_del_node() will remove the given node, including all its
2064 * subnodes if any, from the blob.
2065 *
2066 * This function will delete data from the blob, and will therefore
2067 * change the offsets of some existing nodes.
2068 *
2069 * returns:
2070 * 0, on success
2071 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2072 * -FDT_ERR_BADLAYOUT,
2073 * -FDT_ERR_BADMAGIC,
2074 * -FDT_ERR_BADVERSION,
2075 * -FDT_ERR_BADSTATE,
2076 * -FDT_ERR_BADSTRUCTURE,
2077 * -FDT_ERR_TRUNCATED, standard meanings
2078 */
2079int fdt_del_node(void *fdt, int nodeoffset);
2080
2081/**
2082 * fdt_overlay_apply - Applies a DT overlay on a base DT
2083 * @fdt: pointer to the base device tree blob
2084 * @fdto: pointer to the device tree overlay blob
2085 *
2086 * fdt_overlay_apply() will apply the given device tree overlay on the
2087 * given base device tree.
2088 *
2089 * Expect the base device tree to be modified, even if the function
2090 * returns an error.
2091 *
2092 * returns:
2093 * 0, on success
2094 * -FDT_ERR_NOSPACE, there's not enough space in the base device tree
2095 * -FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
2096 * properties in the base DT
2097 * -FDT_ERR_BADPHANDLE,
2098 * -FDT_ERR_BADOVERLAY,
2099 * -FDT_ERR_NOPHANDLES,
2100 * -FDT_ERR_INTERNAL,
2101 * -FDT_ERR_BADLAYOUT,
2102 * -FDT_ERR_BADMAGIC,
2103 * -FDT_ERR_BADOFFSET,
2104 * -FDT_ERR_BADPATH,
2105 * -FDT_ERR_BADVERSION,
2106 * -FDT_ERR_BADSTRUCTURE,
2107 * -FDT_ERR_BADSTATE,
2108 * -FDT_ERR_TRUNCATED, standard meanings
2109 */
2110int fdt_overlay_apply(void *fdt, void *fdto);
2111
2112/**********************************************************************/
2113/* Debugging / informational functions */
2114/**********************************************************************/
2115
2116const char *fdt_strerror(int errval);
2117
2118#ifdef __cplusplus
2119}
2120#endif
2121
2122#endif /* LIBFDT_H */