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