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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 uint16_t fdt16_ld(const fdt16_t *p)
135{
136 const uint8_t *bp = (const uint8_t *)p;
137
138 return ((uint16_t)bp[0] << 8) | bp[1];
139}
140
141static inline uint32_t fdt32_ld(const fdt32_t *p)
142{
143 const uint8_t *bp = (const uint8_t *)p;
144
145 return ((uint32_t)bp[0] << 24)
146 | ((uint32_t)bp[1] << 16)
147 | ((uint32_t)bp[2] << 8)
148 | bp[3];
149}
150
151static inline void fdt32_st(void *property, uint32_t value)
152{
153 uint8_t *bp = (uint8_t *)property;
154
155 bp[0] = value >> 24;
156 bp[1] = (value >> 16) & 0xff;
157 bp[2] = (value >> 8) & 0xff;
158 bp[3] = value & 0xff;
159}
160
161static inline uint64_t fdt64_ld(const fdt64_t *p)
162{
163 const uint8_t *bp = (const uint8_t *)p;
164
165 return ((uint64_t)bp[0] << 56)
166 | ((uint64_t)bp[1] << 48)
167 | ((uint64_t)bp[2] << 40)
168 | ((uint64_t)bp[3] << 32)
169 | ((uint64_t)bp[4] << 24)
170 | ((uint64_t)bp[5] << 16)
171 | ((uint64_t)bp[6] << 8)
172 | bp[7];
173}
174
175static inline void fdt64_st(void *property, uint64_t value)
176{
177 uint8_t *bp = (uint8_t *)property;
178
179 bp[0] = value >> 56;
180 bp[1] = (value >> 48) & 0xff;
181 bp[2] = (value >> 40) & 0xff;
182 bp[3] = (value >> 32) & 0xff;
183 bp[4] = (value >> 24) & 0xff;
184 bp[5] = (value >> 16) & 0xff;
185 bp[6] = (value >> 8) & 0xff;
186 bp[7] = value & 0xff;
187}
188
189/**********************************************************************/
190/* Traversal functions */
191/**********************************************************************/
192
193int fdt_next_node(const void *fdt, int offset, int *depth);
194
195/**
196 * fdt_first_subnode() - get offset of first direct subnode
197 * @fdt: FDT blob
198 * @offset: Offset of node to check
199 *
200 * Return: offset of first subnode, or -FDT_ERR_NOTFOUND if there is none
201 */
202int fdt_first_subnode(const void *fdt, int offset);
203
204/**
205 * fdt_next_subnode() - get offset of next direct subnode
206 * @fdt: FDT blob
207 * @offset: Offset of previous subnode
208 *
209 * After first calling fdt_first_subnode(), call this function repeatedly to
210 * get direct subnodes of a parent node.
211 *
212 * Return: offset of next subnode, or -FDT_ERR_NOTFOUND if there are no more
213 * subnodes
214 */
215int fdt_next_subnode(const void *fdt, int offset);
216
217/**
218 * fdt_for_each_subnode - iterate over all subnodes of a parent
219 *
220 * @node: child node (int, lvalue)
221 * @fdt: FDT blob (const void *)
222 * @parent: parent node (int)
223 *
224 * This is actually a wrapper around a for loop and would be used like so:
225 *
226 * fdt_for_each_subnode(node, fdt, parent) {
227 * Use node
228 * ...
229 * }
230 *
231 * if ((node < 0) && (node != -FDT_ERR_NOTFOUND)) {
232 * Error handling
233 * }
234 *
235 * Note that this is implemented as a macro and @node is used as
236 * iterator in the loop. The parent variable be constant or even a
237 * literal.
238 */
239#define fdt_for_each_subnode(node, fdt, parent) \
240 for (node = fdt_first_subnode(fdt, parent); \
241 node >= 0; \
242 node = fdt_next_subnode(fdt, node))
243
244/**********************************************************************/
245/* General functions */
246/**********************************************************************/
247#define fdt_get_header(fdt, field) \
248 (fdt32_ld(&((const struct fdt_header *)(fdt))->field))
249#define fdt_magic(fdt) (fdt_get_header(fdt, magic))
250#define fdt_totalsize(fdt) (fdt_get_header(fdt, totalsize))
251#define fdt_off_dt_struct(fdt) (fdt_get_header(fdt, off_dt_struct))
252#define fdt_off_dt_strings(fdt) (fdt_get_header(fdt, off_dt_strings))
253#define fdt_off_mem_rsvmap(fdt) (fdt_get_header(fdt, off_mem_rsvmap))
254#define fdt_version(fdt) (fdt_get_header(fdt, version))
255#define fdt_last_comp_version(fdt) (fdt_get_header(fdt, last_comp_version))
256#define fdt_boot_cpuid_phys(fdt) (fdt_get_header(fdt, boot_cpuid_phys))
257#define fdt_size_dt_strings(fdt) (fdt_get_header(fdt, size_dt_strings))
258#define fdt_size_dt_struct(fdt) (fdt_get_header(fdt, size_dt_struct))
259
260#define fdt_set_hdr_(name) \
261 static inline void fdt_set_##name(void *fdt, uint32_t val) \
262 { \
263 struct fdt_header *fdth = (struct fdt_header *)fdt; \
264 fdth->name = cpu_to_fdt32(val); \
265 }
266fdt_set_hdr_(magic);
267fdt_set_hdr_(totalsize);
268fdt_set_hdr_(off_dt_struct);
269fdt_set_hdr_(off_dt_strings);
270fdt_set_hdr_(off_mem_rsvmap);
271fdt_set_hdr_(version);
272fdt_set_hdr_(last_comp_version);
273fdt_set_hdr_(boot_cpuid_phys);
274fdt_set_hdr_(size_dt_strings);
275fdt_set_hdr_(size_dt_struct);
276#undef fdt_set_hdr_
277
278/**
279 * fdt_header_size - return the size of the tree's header
280 * @fdt: pointer to a flattened device tree
281 *
282 * Return: size of DTB header in bytes
283 */
284size_t fdt_header_size(const void *fdt);
285
286/**
287 * fdt_header_size_ - internal function to get header size from a version number
288 * @version: devicetree version number
289 *
290 * Return: size of DTB header in bytes
291 */
292size_t fdt_header_size_(uint32_t version);
293
294/**
295 * fdt_check_header - sanity check a device tree header
296 * @fdt: pointer to data which might be a flattened device tree
297 *
298 * fdt_check_header() checks that the given buffer contains what
299 * appears to be a flattened device tree, and that the header contains
300 * valid information (to the extent that can be determined from the
301 * header alone).
302 *
303 * returns:
304 * 0, if the buffer appears to contain a valid device tree
305 * -FDT_ERR_BADMAGIC,
306 * -FDT_ERR_BADVERSION,
307 * -FDT_ERR_BADSTATE,
308 * -FDT_ERR_TRUNCATED, standard meanings, as above
309 */
310int fdt_check_header(const void *fdt);
311
312/**
313 * fdt_move - move a device tree around in memory
314 * @fdt: pointer to the device tree to move
315 * @buf: pointer to memory where the device is to be moved
316 * @bufsize: size of the memory space at buf
317 *
318 * fdt_move() relocates, if possible, the device tree blob located at
319 * fdt to the buffer at buf of size bufsize. The buffer may overlap
320 * with the existing device tree blob at fdt. Therefore,
321 * fdt_move(fdt, fdt, fdt_totalsize(fdt))
322 * should always succeed.
323 *
324 * returns:
325 * 0, on success
326 * -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
327 * -FDT_ERR_BADMAGIC,
328 * -FDT_ERR_BADVERSION,
329 * -FDT_ERR_BADSTATE, standard meanings
330 */
331int fdt_move(const void *fdt, void *buf, int bufsize);
332
333/**********************************************************************/
334/* Read-only functions */
335/**********************************************************************/
336
337int fdt_check_full(const void *fdt, size_t bufsize);
338
339/**
340 * fdt_get_string - retrieve a string from the strings block of a device tree
341 * @fdt: pointer to the device tree blob
342 * @stroffset: offset of the string within the strings block (native endian)
343 * @lenp: optional pointer to return the string's length
344 *
345 * fdt_get_string() retrieves a pointer to a single string from the
346 * strings block of the device tree blob at fdt, and optionally also
347 * returns the string's length in *lenp.
348 *
349 * returns:
350 * a pointer to the string, on success
351 * NULL, if stroffset is out of bounds, or doesn't point to a valid string
352 */
353const char *fdt_get_string(const void *fdt, int stroffset, int *lenp);
354
355/**
356 * fdt_string - retrieve a string from the strings block of a device tree
357 * @fdt: pointer to the device tree blob
358 * @stroffset: offset of the string within the strings block (native endian)
359 *
360 * fdt_string() retrieves a pointer to a single string from the
361 * strings block of the device tree blob at fdt.
362 *
363 * returns:
364 * a pointer to the string, on success
365 * NULL, if stroffset is out of bounds, or doesn't point to a valid string
366 */
367const char *fdt_string(const void *fdt, int stroffset);
368
369/**
370 * fdt_find_max_phandle - find and return the highest phandle in a tree
371 * @fdt: pointer to the device tree blob
372 * @phandle: return location for the highest phandle value found in the tree
373 *
374 * fdt_find_max_phandle() finds the highest phandle value in the given device
375 * tree. The value returned in @phandle is only valid if the function returns
376 * success.
377 *
378 * returns:
379 * 0 on success or a negative error code on failure
380 */
381int fdt_find_max_phandle(const void *fdt, uint32_t *phandle);
382
383/**
384 * fdt_get_max_phandle - retrieves the highest phandle in a tree
385 * @fdt: pointer to the device tree blob
386 *
387 * fdt_get_max_phandle retrieves the highest phandle in the given
388 * device tree. This will ignore badly formatted phandles, or phandles
389 * with a value of 0 or -1.
390 *
391 * This function is deprecated in favour of fdt_find_max_phandle().
392 *
393 * returns:
394 * the highest phandle on success
395 * 0, if no phandle was found in the device tree
396 * -1, if an error occurred
397 */
398static inline uint32_t fdt_get_max_phandle(const void *fdt)
399{
400 uint32_t phandle;
401 int err;
402
403 err = fdt_find_max_phandle(fdt, &phandle);
404 if (err < 0)
405 return (uint32_t)-1;
406
407 return phandle;
408}
409
410/**
411 * fdt_generate_phandle - return a new, unused phandle for a device tree blob
412 * @fdt: pointer to the device tree blob
413 * @phandle: return location for the new phandle
414 *
415 * Walks the device tree blob and looks for the highest phandle value. On
416 * success, the new, unused phandle value (one higher than the previously
417 * highest phandle value in the device tree blob) will be returned in the
418 * @phandle parameter.
419 *
420 * Return: 0 on success or a negative error-code on failure
421 */
422int fdt_generate_phandle(const void *fdt, uint32_t *phandle);
423
424/**
425 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
426 * @fdt: pointer to the device tree blob
427 *
428 * Returns the number of entries in the device tree blob's memory
429 * reservation map. This does not include the terminating 0,0 entry
430 * or any other (0,0) entries reserved for expansion.
431 *
432 * returns:
433 * the number of entries
434 */
435int fdt_num_mem_rsv(const void *fdt);
436
437/**
438 * fdt_get_mem_rsv - retrieve one memory reserve map entry
439 * @fdt: pointer to the device tree blob
440 * @n: index of reserve map entry
441 * @address: pointer to 64-bit variable to hold the start address
442 * @size: pointer to 64-bit variable to hold the size of the entry
443 *
444 * On success, @address and @size will contain the address and size of
445 * the n-th reserve map entry from the device tree blob, in
446 * native-endian format.
447 *
448 * returns:
449 * 0, on success
450 * -FDT_ERR_BADMAGIC,
451 * -FDT_ERR_BADVERSION,
452 * -FDT_ERR_BADSTATE, standard meanings
453 */
454int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
455
456/**
457 * fdt_subnode_offset_namelen - find a subnode based on substring
458 * @fdt: pointer to the device tree blob
459 * @parentoffset: structure block offset of a node
460 * @name: name of the subnode to locate
461 * @namelen: number of characters of name to consider
462 *
463 * Identical to fdt_subnode_offset(), but only examine the first
464 * namelen characters of name for matching the subnode name. This is
465 * useful for finding subnodes based on a portion of a larger string,
466 * such as a full path.
467 *
468 * Return: offset of the subnode or -FDT_ERR_NOTFOUND if name not found.
469 */
470#ifndef SWIG /* Not available in Python */
471int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
472 const char *name, int namelen);
473#endif
474/**
475 * fdt_subnode_offset - find a subnode of a given node
476 * @fdt: pointer to the device tree blob
477 * @parentoffset: structure block offset of a node
478 * @name: name of the subnode to locate
479 *
480 * fdt_subnode_offset() finds a subnode of the node at structure block
481 * offset parentoffset with the given name. name may include a unit
482 * address, in which case fdt_subnode_offset() will find the subnode
483 * with that unit address, or the unit address may be omitted, in
484 * which case fdt_subnode_offset() will find an arbitrary subnode
485 * whose name excluding unit address matches the given name.
486 *
487 * returns:
488 * structure block offset of the requested subnode (>=0), on success
489 * -FDT_ERR_NOTFOUND, if the requested subnode does not exist
490 * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
491 * tag
492 * -FDT_ERR_BADMAGIC,
493 * -FDT_ERR_BADVERSION,
494 * -FDT_ERR_BADSTATE,
495 * -FDT_ERR_BADSTRUCTURE,
496 * -FDT_ERR_TRUNCATED, standard meanings.
497 */
498int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
499
500/**
501 * fdt_path_offset_namelen - find a tree node by its full path
502 * @fdt: pointer to the device tree blob
503 * @path: full path of the node to locate
504 * @namelen: number of characters of path to consider
505 *
506 * Identical to fdt_path_offset(), but only consider the first namelen
507 * characters of path as the path name.
508 *
509 * Return: offset of the node or negative libfdt error value otherwise
510 */
511#ifndef SWIG /* Not available in Python */
512int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen);
513#endif
514
515/**
516 * fdt_path_offset - find a tree node by its full path
517 * @fdt: pointer to the device tree blob
518 * @path: full path of the node to locate
519 *
520 * fdt_path_offset() finds a node of a given path in the device tree.
521 * Each path component may omit the unit address portion, but the
522 * results of this are undefined if any such path component is
523 * ambiguous (that is if there are multiple nodes at the relevant
524 * level matching the given component, differentiated only by unit
525 * address).
526 *
527 * returns:
528 * structure block offset of the node with the requested path (>=0), on
529 * success
530 * -FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
531 * -FDT_ERR_NOTFOUND, if the requested node does not exist
532 * -FDT_ERR_BADMAGIC,
533 * -FDT_ERR_BADVERSION,
534 * -FDT_ERR_BADSTATE,
535 * -FDT_ERR_BADSTRUCTURE,
536 * -FDT_ERR_TRUNCATED, standard meanings.
537 */
538int fdt_path_offset(const void *fdt, const char *path);
539
540/**
541 * fdt_get_name - retrieve the name of a given node
542 * @fdt: pointer to the device tree blob
543 * @nodeoffset: structure block offset of the starting node
544 * @lenp: pointer to an integer variable (will be overwritten) or NULL
545 *
546 * fdt_get_name() retrieves the name (including unit address) of the
547 * device tree node at structure block offset nodeoffset. If lenp is
548 * non-NULL, the length of this name is also returned, in the integer
549 * pointed to by lenp.
550 *
551 * returns:
552 * pointer to the node's name, on success
553 * If lenp is non-NULL, *lenp contains the length of that name
554 * (>=0)
555 * NULL, on error
556 * if lenp is non-NULL *lenp contains an error code (<0):
557 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
558 * tag
559 * -FDT_ERR_BADMAGIC,
560 * -FDT_ERR_BADVERSION,
561 * -FDT_ERR_BADSTATE, standard meanings
562 */
563const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
564
565/**
566 * fdt_first_property_offset - find the offset of a node's first property
567 * @fdt: pointer to the device tree blob
568 * @nodeoffset: structure block offset of a node
569 *
570 * fdt_first_property_offset() finds the first property of the node at
571 * the given structure block offset.
572 *
573 * returns:
574 * structure block offset of the property (>=0), on success
575 * -FDT_ERR_NOTFOUND, if the requested node has no properties
576 * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
577 * -FDT_ERR_BADMAGIC,
578 * -FDT_ERR_BADVERSION,
579 * -FDT_ERR_BADSTATE,
580 * -FDT_ERR_BADSTRUCTURE,
581 * -FDT_ERR_TRUNCATED, standard meanings.
582 */
583int fdt_first_property_offset(const void *fdt, int nodeoffset);
584
585/**
586 * fdt_next_property_offset - step through a node's properties
587 * @fdt: pointer to the device tree blob
588 * @offset: structure block offset of a property
589 *
590 * fdt_next_property_offset() finds the property immediately after the
591 * one at the given structure block offset. This will be a property
592 * of the same node as the given property.
593 *
594 * returns:
595 * structure block offset of the next property (>=0), on success
596 * -FDT_ERR_NOTFOUND, if the given property is the last in its node
597 * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag
598 * -FDT_ERR_BADMAGIC,
599 * -FDT_ERR_BADVERSION,
600 * -FDT_ERR_BADSTATE,
601 * -FDT_ERR_BADSTRUCTURE,
602 * -FDT_ERR_TRUNCATED, standard meanings.
603 */
604int fdt_next_property_offset(const void *fdt, int offset);
605
606/**
607 * fdt_for_each_property_offset - iterate over all properties of a node
608 *
609 * @property: property offset (int, lvalue)
610 * @fdt: FDT blob (const void *)
611 * @node: node offset (int)
612 *
613 * This is actually a wrapper around a for loop and would be used like so:
614 *
615 * fdt_for_each_property_offset(property, fdt, node) {
616 * Use property
617 * ...
618 * }
619 *
620 * if ((property < 0) && (property != -FDT_ERR_NOTFOUND)) {
621 * Error handling
622 * }
623 *
624 * Note that this is implemented as a macro and property is used as
625 * iterator in the loop. The node variable can be constant or even a
626 * literal.
627 */
628#define fdt_for_each_property_offset(property, fdt, node) \
629 for (property = fdt_first_property_offset(fdt, node); \
630 property >= 0; \
631 property = fdt_next_property_offset(fdt, property))
632
633/**
634 * fdt_get_property_by_offset - retrieve the property at a given offset
635 * @fdt: pointer to the device tree blob
636 * @offset: offset of the property to retrieve
637 * @lenp: pointer to an integer variable (will be overwritten) or NULL
638 *
639 * fdt_get_property_by_offset() retrieves a pointer to the
640 * fdt_property structure within the device tree blob at the given
641 * offset. If lenp is non-NULL, the length of the property value is
642 * also returned, in the integer pointed to by lenp.
643 *
644 * Note that this code only works on device tree versions >= 16. fdt_getprop()
645 * works on all versions.
646 *
647 * returns:
648 * pointer to the structure representing the property
649 * if lenp is non-NULL, *lenp contains the length of the property
650 * value (>=0)
651 * NULL, on error
652 * if lenp is non-NULL, *lenp contains an error code (<0):
653 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
654 * -FDT_ERR_BADMAGIC,
655 * -FDT_ERR_BADVERSION,
656 * -FDT_ERR_BADSTATE,
657 * -FDT_ERR_BADSTRUCTURE,
658 * -FDT_ERR_TRUNCATED, standard meanings
659 */
660const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
661 int offset,
662 int *lenp);
663static inline struct fdt_property *fdt_get_property_by_offset_w(void *fdt,
664 int offset,
665 int *lenp)
666{
667 return (struct fdt_property *)(uintptr_t)
668 fdt_get_property_by_offset(fdt, offset, lenp);
669}
670
671/**
672 * fdt_get_property_namelen - find a property based on substring
673 * @fdt: pointer to the device tree blob
674 * @nodeoffset: offset of the node whose property to find
675 * @name: name of the property to find
676 * @namelen: number of characters of name to consider
677 * @lenp: pointer to an integer variable (will be overwritten) or NULL
678 *
679 * Identical to fdt_get_property(), but only examine the first namelen
680 * characters of name for matching the property name.
681 *
682 * Return: pointer to the structure representing the property, or NULL
683 * if not found
684 */
685#ifndef SWIG /* Not available in Python */
686const struct fdt_property *fdt_get_property_namelen(const void *fdt,
687 int nodeoffset,
688 const char *name,
689 int namelen, int *lenp);
690#endif
691
692/**
693 * fdt_get_property - find a given property in a given node
694 * @fdt: pointer to the device tree blob
695 * @nodeoffset: offset of the node whose property to find
696 * @name: name of the property to find
697 * @lenp: pointer to an integer variable (will be overwritten) or NULL
698 *
699 * fdt_get_property() retrieves a pointer to the fdt_property
700 * structure within the device tree blob corresponding to the property
701 * named 'name' of the node at offset nodeoffset. If lenp is
702 * non-NULL, the length of the property value is also returned, in the
703 * integer pointed to by lenp.
704 *
705 * returns:
706 * pointer to the structure representing the property
707 * if lenp is non-NULL, *lenp contains the length of the property
708 * value (>=0)
709 * NULL, on error
710 * if lenp is non-NULL, *lenp contains an error code (<0):
711 * -FDT_ERR_NOTFOUND, node does not have named property
712 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
713 * tag
714 * -FDT_ERR_BADMAGIC,
715 * -FDT_ERR_BADVERSION,
716 * -FDT_ERR_BADSTATE,
717 * -FDT_ERR_BADSTRUCTURE,
718 * -FDT_ERR_TRUNCATED, standard meanings
719 */
720const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
721 const char *name, int *lenp);
722static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
723 const char *name,
724 int *lenp)
725{
726 return (struct fdt_property *)(uintptr_t)
727 fdt_get_property(fdt, nodeoffset, name, lenp);
728}
729
730/**
731 * fdt_getprop_by_offset - retrieve the value of a property at a given offset
732 * @fdt: pointer to the device tree blob
733 * @offset: offset of the property to read
734 * @namep: pointer to a string variable (will be overwritten) or NULL
735 * @lenp: pointer to an integer variable (will be overwritten) or NULL
736 *
737 * fdt_getprop_by_offset() retrieves a pointer to the value of the
738 * property at structure block offset 'offset' (this will be a pointer
739 * to within the device blob itself, not a copy of the value). If
740 * lenp is non-NULL, the length of the property value is also
741 * returned, in the integer pointed to by lenp. If namep is non-NULL,
742 * the property's namne will also be returned in the char * pointed to
743 * by namep (this will be a pointer to within the device tree's string
744 * block, not a new copy of the name).
745 *
746 * returns:
747 * pointer to the property's value
748 * if lenp is non-NULL, *lenp contains the length of the property
749 * value (>=0)
750 * if namep is non-NULL *namep contiains a pointer to the property
751 * name.
752 * NULL, on error
753 * if lenp is non-NULL, *lenp contains an error code (<0):
754 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
755 * -FDT_ERR_BADMAGIC,
756 * -FDT_ERR_BADVERSION,
757 * -FDT_ERR_BADSTATE,
758 * -FDT_ERR_BADSTRUCTURE,
759 * -FDT_ERR_TRUNCATED, standard meanings
760 */
761#ifndef SWIG /* This function is not useful in Python */
762const void *fdt_getprop_by_offset(const void *fdt, int offset,
763 const char **namep, int *lenp);
764#endif
765
766/**
767 * fdt_getprop_namelen - get property value based on substring
768 * @fdt: pointer to the device tree blob
769 * @nodeoffset: offset of the node whose property to find
770 * @name: name of the property to find
771 * @namelen: number of characters of name to consider
772 * @lenp: pointer to an integer variable (will be overwritten) or NULL
773 *
774 * Identical to fdt_getprop(), but only examine the first namelen
775 * characters of name for matching the property name.
776 *
777 * Return: pointer to the property's value or NULL on error
778 */
779#ifndef SWIG /* Not available in Python */
780const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
781 const char *name, int namelen, int *lenp);
782static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset,
783 const char *name, int namelen,
784 int *lenp)
785{
786 return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name,
787 namelen, lenp);
788}
789#endif
790
791/**
792 * fdt_getprop - retrieve the value of a given property
793 * @fdt: pointer to the device tree blob
794 * @nodeoffset: offset of the node whose property to find
795 * @name: name of the property to find
796 * @lenp: pointer to an integer variable (will be overwritten) or NULL
797 *
798 * fdt_getprop() retrieves a pointer to the value of the property
799 * named @name of the node at offset @nodeoffset (this will be a
800 * pointer to within the device blob itself, not a copy of the value).
801 * If @lenp is non-NULL, the length of the property value is also
802 * returned, in the integer pointed to by @lenp.
803 *
804 * returns:
805 * pointer to the property's value
806 * if lenp is non-NULL, *lenp contains the length of the property
807 * value (>=0)
808 * NULL, on error
809 * if lenp is non-NULL, *lenp contains an error code (<0):
810 * -FDT_ERR_NOTFOUND, node does not have named property
811 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
812 * tag
813 * -FDT_ERR_BADMAGIC,
814 * -FDT_ERR_BADVERSION,
815 * -FDT_ERR_BADSTATE,
816 * -FDT_ERR_BADSTRUCTURE,
817 * -FDT_ERR_TRUNCATED, standard meanings
818 */
819const void *fdt_getprop(const void *fdt, int nodeoffset,
820 const char *name, int *lenp);
821static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
822 const char *name, int *lenp)
823{
824 return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
825}
826
827/**
828 * fdt_get_phandle - retrieve the phandle of a given node
829 * @fdt: pointer to the device tree blob
830 * @nodeoffset: structure block offset of the node
831 *
832 * fdt_get_phandle() retrieves the phandle of the device tree node at
833 * structure block offset nodeoffset.
834 *
835 * returns:
836 * the phandle of the node at nodeoffset, on success (!= 0, != -1)
837 * 0, if the node has no phandle, or another error occurs
838 */
839uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
840
841/**
842 * fdt_get_alias_namelen - get alias based on substring
843 * @fdt: pointer to the device tree blob
844 * @name: name of the alias th look up
845 * @namelen: number of characters of name to consider
846 *
847 * Identical to fdt_get_alias(), but only examine the first @namelen
848 * characters of @name for matching the alias name.
849 *
850 * Return: a pointer to the expansion of the alias named @name, if it exists,
851 * NULL otherwise
852 */
853#ifndef SWIG /* Not available in Python */
854const char *fdt_get_alias_namelen(const void *fdt,
855 const char *name, int namelen);
856#endif
857
858/**
859 * fdt_get_alias - retrieve the path referenced by a given alias
860 * @fdt: pointer to the device tree blob
861 * @name: name of the alias th look up
862 *
863 * fdt_get_alias() retrieves the value of a given alias. That is, the
864 * value of the property named @name in the node /aliases.
865 *
866 * returns:
867 * a pointer to the expansion of the alias named 'name', if it exists
868 * NULL, if the given alias or the /aliases node does not exist
869 */
870const char *fdt_get_alias(const void *fdt, const char *name);
871
872/**
873 * fdt_get_path - determine the full path of a node
874 * @fdt: pointer to the device tree blob
875 * @nodeoffset: offset of the node whose path to find
876 * @buf: character buffer to contain the returned path (will be overwritten)
877 * @buflen: size of the character buffer at buf
878 *
879 * fdt_get_path() computes the full path of the node at offset
880 * nodeoffset, and records that path in the buffer at buf.
881 *
882 * NOTE: This function is expensive, as it must scan the device tree
883 * structure from the start to nodeoffset.
884 *
885 * returns:
886 * 0, on success
887 * buf contains the absolute path of the node at
888 * nodeoffset, as a NUL-terminated string.
889 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
890 * -FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
891 * characters and will not fit in the given buffer.
892 * -FDT_ERR_BADMAGIC,
893 * -FDT_ERR_BADVERSION,
894 * -FDT_ERR_BADSTATE,
895 * -FDT_ERR_BADSTRUCTURE, standard meanings
896 */
897int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
898
899/**
900 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
901 * @fdt: pointer to the device tree blob
902 * @nodeoffset: offset of the node whose parent to find
903 * @supernodedepth: depth of the ancestor to find
904 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
905 *
906 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
907 * at a specific depth from the root (where the root itself has depth
908 * 0, its immediate subnodes depth 1 and so forth). So
909 * fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
910 * will always return 0, the offset of the root node. If the node at
911 * nodeoffset has depth D, then:
912 * fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
913 * will return nodeoffset itself.
914 *
915 * NOTE: This function is expensive, as it must scan the device tree
916 * structure from the start to nodeoffset.
917 *
918 * returns:
919 * structure block offset of the node at node offset's ancestor
920 * of depth supernodedepth (>=0), on success
921 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
922 * -FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of
923 * nodeoffset
924 * -FDT_ERR_BADMAGIC,
925 * -FDT_ERR_BADVERSION,
926 * -FDT_ERR_BADSTATE,
927 * -FDT_ERR_BADSTRUCTURE, standard meanings
928 */
929int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
930 int supernodedepth, int *nodedepth);
931
932/**
933 * fdt_node_depth - find the depth of a given node
934 * @fdt: pointer to the device tree blob
935 * @nodeoffset: offset of the node whose parent to find
936 *
937 * fdt_node_depth() finds the depth of a given node. The root node
938 * has depth 0, its immediate subnodes depth 1 and so forth.
939 *
940 * NOTE: This function is expensive, as it must scan the device tree
941 * structure from the start to nodeoffset.
942 *
943 * returns:
944 * depth of the node at nodeoffset (>=0), on success
945 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
946 * -FDT_ERR_BADMAGIC,
947 * -FDT_ERR_BADVERSION,
948 * -FDT_ERR_BADSTATE,
949 * -FDT_ERR_BADSTRUCTURE, standard meanings
950 */
951int fdt_node_depth(const void *fdt, int nodeoffset);
952
953/**
954 * fdt_parent_offset - find the parent of a given node
955 * @fdt: pointer to the device tree blob
956 * @nodeoffset: offset of the node whose parent to find
957 *
958 * fdt_parent_offset() locates the parent node of a given node (that
959 * is, it finds the offset of the node which contains the node at
960 * nodeoffset as a subnode).
961 *
962 * NOTE: This function is expensive, as it must scan the device tree
963 * structure from the start to nodeoffset, *twice*.
964 *
965 * returns:
966 * structure block offset of the parent of the node at nodeoffset
967 * (>=0), on success
968 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
969 * -FDT_ERR_BADMAGIC,
970 * -FDT_ERR_BADVERSION,
971 * -FDT_ERR_BADSTATE,
972 * -FDT_ERR_BADSTRUCTURE, standard meanings
973 */
974int fdt_parent_offset(const void *fdt, int nodeoffset);
975
976/**
977 * fdt_node_offset_by_prop_value - find nodes with a given property value
978 * @fdt: pointer to the device tree blob
979 * @startoffset: only find nodes after this offset
980 * @propname: property name to check
981 * @propval: property value to search for
982 * @proplen: length of the value in propval
983 *
984 * fdt_node_offset_by_prop_value() returns the offset of the first
985 * node after startoffset, which has a property named propname whose
986 * value is of length proplen and has value equal to propval; or if
987 * startoffset is -1, the very first such node in the tree.
988 *
989 * To iterate through all nodes matching the criterion, the following
990 * idiom can be used:
991 * offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
992 * propval, proplen);
993 * while (offset != -FDT_ERR_NOTFOUND) {
994 * // other code here
995 * offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
996 * propval, proplen);
997 * }
998 *
999 * Note the -1 in the first call to the function, if 0 is used here
1000 * instead, the function will never locate the root node, even if it
1001 * matches the criterion.
1002 *
1003 * returns:
1004 * structure block offset of the located node (>= 0, >startoffset),
1005 * on success
1006 * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
1007 * tree after startoffset
1008 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1009 * -FDT_ERR_BADMAGIC,
1010 * -FDT_ERR_BADVERSION,
1011 * -FDT_ERR_BADSTATE,
1012 * -FDT_ERR_BADSTRUCTURE, standard meanings
1013 */
1014int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
1015 const char *propname,
1016 const void *propval, int proplen);
1017
1018/**
1019 * fdt_node_offset_by_phandle - find the node with a given phandle
1020 * @fdt: pointer to the device tree blob
1021 * @phandle: phandle value
1022 *
1023 * fdt_node_offset_by_phandle() returns the offset of the node
1024 * which has the given phandle value. If there is more than one node
1025 * in the tree with the given phandle (an invalid tree), results are
1026 * undefined.
1027 *
1028 * returns:
1029 * structure block offset of the located node (>= 0), on success
1030 * -FDT_ERR_NOTFOUND, no node with that phandle exists
1031 * -FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
1032 * -FDT_ERR_BADMAGIC,
1033 * -FDT_ERR_BADVERSION,
1034 * -FDT_ERR_BADSTATE,
1035 * -FDT_ERR_BADSTRUCTURE, standard meanings
1036 */
1037int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
1038
1039/**
1040 * fdt_node_check_compatible - check a node's compatible property
1041 * @fdt: pointer to the device tree blob
1042 * @nodeoffset: offset of a tree node
1043 * @compatible: string to match against
1044 *
1045 * fdt_node_check_compatible() returns 0 if the given node contains a
1046 * @compatible property with the given string as one of its elements,
1047 * it returns non-zero otherwise, or on error.
1048 *
1049 * returns:
1050 * 0, if the node has a 'compatible' property listing the given string
1051 * 1, if the node has a 'compatible' property, but it does not list
1052 * the given string
1053 * -FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
1054 * -FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
1055 * -FDT_ERR_BADMAGIC,
1056 * -FDT_ERR_BADVERSION,
1057 * -FDT_ERR_BADSTATE,
1058 * -FDT_ERR_BADSTRUCTURE, standard meanings
1059 */
1060int fdt_node_check_compatible(const void *fdt, int nodeoffset,
1061 const char *compatible);
1062
1063/**
1064 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
1065 * @fdt: pointer to the device tree blob
1066 * @startoffset: only find nodes after this offset
1067 * @compatible: 'compatible' string to match against
1068 *
1069 * fdt_node_offset_by_compatible() returns the offset of the first
1070 * node after startoffset, which has a 'compatible' property which
1071 * lists the given compatible string; or if startoffset is -1, the
1072 * very first such node in the tree.
1073 *
1074 * To iterate through all nodes matching the criterion, the following
1075 * idiom can be used:
1076 * offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
1077 * while (offset != -FDT_ERR_NOTFOUND) {
1078 * // other code here
1079 * offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
1080 * }
1081 *
1082 * Note the -1 in the first call to the function, if 0 is used here
1083 * instead, the function will never locate the root node, even if it
1084 * matches the criterion.
1085 *
1086 * returns:
1087 * structure block offset of the located node (>= 0, >startoffset),
1088 * on success
1089 * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
1090 * tree after startoffset
1091 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1092 * -FDT_ERR_BADMAGIC,
1093 * -FDT_ERR_BADVERSION,
1094 * -FDT_ERR_BADSTATE,
1095 * -FDT_ERR_BADSTRUCTURE, standard meanings
1096 */
1097int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
1098 const char *compatible);
1099
1100/**
1101 * fdt_stringlist_contains - check a string list property for a string
1102 * @strlist: Property containing a list of strings to check
1103 * @listlen: Length of property
1104 * @str: String to search for
1105 *
1106 * This is a utility function provided for convenience. The list contains
1107 * one or more strings, each terminated by \0, as is found in a device tree
1108 * "compatible" property.
1109 *
1110 * Return: 1 if the string is found in the list, 0 not found, or invalid list
1111 */
1112int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
1113
1114/**
1115 * fdt_stringlist_count - count the number of strings in a string list
1116 * @fdt: pointer to the device tree blob
1117 * @nodeoffset: offset of a tree node
1118 * @property: name of the property containing the string list
1119 *
1120 * Return:
1121 * the number of strings in the given property
1122 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1123 * -FDT_ERR_NOTFOUND if the property does not exist
1124 */
1125int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property);
1126
1127/**
1128 * fdt_stringlist_search - find a string in a string list and return its index
1129 * @fdt: pointer to the device tree blob
1130 * @nodeoffset: offset of a tree node
1131 * @property: name of the property containing the string list
1132 * @string: string to look up in the string list
1133 *
1134 * Note that it is possible for this function to succeed on property values
1135 * that are not NUL-terminated. That's because the function will stop after
1136 * finding the first occurrence of @string. This can for example happen with
1137 * small-valued cell properties, such as #address-cells, when searching for
1138 * the empty string.
1139 *
1140 * return:
1141 * the index of the string in the list of strings
1142 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1143 * -FDT_ERR_NOTFOUND if the property does not exist or does not contain
1144 * the given string
1145 */
1146int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
1147 const char *string);
1148
1149/**
1150 * fdt_stringlist_get() - obtain the string at a given index in a string list
1151 * @fdt: pointer to the device tree blob
1152 * @nodeoffset: offset of a tree node
1153 * @property: name of the property containing the string list
1154 * @index: index of the string to return
1155 * @lenp: return location for the string length or an error code on failure
1156 *
1157 * Note that this will successfully extract strings from properties with
1158 * non-NUL-terminated values. For example on small-valued cell properties
1159 * this function will return the empty string.
1160 *
1161 * If non-NULL, the length of the string (on success) or a negative error-code
1162 * (on failure) will be stored in the integer pointer to by lenp.
1163 *
1164 * Return:
1165 * A pointer to the string at the given index in the string list or NULL on
1166 * failure. On success the length of the string will be stored in the memory
1167 * location pointed to by the lenp parameter, if non-NULL. On failure one of
1168 * the following negative error codes will be returned in the lenp parameter
1169 * (if non-NULL):
1170 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1171 * -FDT_ERR_NOTFOUND if the property does not exist
1172 */
1173const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
1174 const char *property, int index,
1175 int *lenp);
1176
1177/**********************************************************************/
1178/* Read-only functions (addressing related) */
1179/**********************************************************************/
1180
1181/**
1182 * FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells
1183 *
1184 * This is the maximum value for #address-cells, #size-cells and
1185 * similar properties that will be processed by libfdt. IEE1275
1186 * requires that OF implementations handle values up to 4.
1187 * Implementations may support larger values, but in practice higher
1188 * values aren't used.
1189 */
1190#define FDT_MAX_NCELLS 4
1191
1192/**
1193 * fdt_address_cells - retrieve address size for a bus represented in the tree
1194 * @fdt: pointer to the device tree blob
1195 * @nodeoffset: offset of the node to find the address size for
1196 *
1197 * When the node has a valid #address-cells property, returns its value.
1198 *
1199 * returns:
1200 * 0 <= n < FDT_MAX_NCELLS, on success
1201 * 2, if the node has no #address-cells property
1202 * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1203 * #address-cells property
1204 * -FDT_ERR_BADMAGIC,
1205 * -FDT_ERR_BADVERSION,
1206 * -FDT_ERR_BADSTATE,
1207 * -FDT_ERR_BADSTRUCTURE,
1208 * -FDT_ERR_TRUNCATED, standard meanings
1209 */
1210int fdt_address_cells(const void *fdt, int nodeoffset);
1211
1212/**
1213 * fdt_size_cells - retrieve address range size for a bus represented in the
1214 * tree
1215 * @fdt: pointer to the device tree blob
1216 * @nodeoffset: offset of the node to find the address range size for
1217 *
1218 * When the node has a valid #size-cells property, returns its value.
1219 *
1220 * returns:
1221 * 0 <= n < FDT_MAX_NCELLS, on success
1222 * 1, if the node has no #size-cells property
1223 * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1224 * #size-cells property
1225 * -FDT_ERR_BADMAGIC,
1226 * -FDT_ERR_BADVERSION,
1227 * -FDT_ERR_BADSTATE,
1228 * -FDT_ERR_BADSTRUCTURE,
1229 * -FDT_ERR_TRUNCATED, standard meanings
1230 */
1231int fdt_size_cells(const void *fdt, int nodeoffset);
1232
1233
1234/**********************************************************************/
1235/* Write-in-place functions */
1236/**********************************************************************/
1237
1238/**
1239 * fdt_setprop_inplace_namelen_partial - change a property's value,
1240 * but not its size
1241 * @fdt: pointer to the device tree blob
1242 * @nodeoffset: offset of the node whose property to change
1243 * @name: name of the property to change
1244 * @namelen: number of characters of name to consider
1245 * @idx: index of the property to change in the array
1246 * @val: pointer to data to replace the property value with
1247 * @len: length of the property value
1248 *
1249 * Identical to fdt_setprop_inplace(), but modifies the given property
1250 * starting from the given index, and using only the first characters
1251 * of the name. It is useful when you want to manipulate only one value of
1252 * an array and you have a string that doesn't end with \0.
1253 *
1254 * Return: 0 on success, negative libfdt error value otherwise
1255 */
1256#ifndef SWIG /* Not available in Python */
1257int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
1258 const char *name, int namelen,
1259 uint32_t idx, const void *val,
1260 int len);
1261#endif
1262
1263/**
1264 * fdt_setprop_inplace - change a property's value, but not its size
1265 * @fdt: pointer to the device tree blob
1266 * @nodeoffset: offset of the node whose property to change
1267 * @name: name of the property to change
1268 * @val: pointer to data to replace the property value with
1269 * @len: length of the property value
1270 *
1271 * fdt_setprop_inplace() replaces the value of a given property with
1272 * the data in val, of length len. This function cannot change the
1273 * size of a property, and so will only work if len is equal to the
1274 * current length of the property.
1275 *
1276 * This function will alter only the bytes in the blob which contain
1277 * the given property value, and will not alter or move any other part
1278 * of the tree.
1279 *
1280 * returns:
1281 * 0, on success
1282 * -FDT_ERR_NOSPACE, if len is not equal to the property's current length
1283 * -FDT_ERR_NOTFOUND, node does not have the named property
1284 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1285 * -FDT_ERR_BADMAGIC,
1286 * -FDT_ERR_BADVERSION,
1287 * -FDT_ERR_BADSTATE,
1288 * -FDT_ERR_BADSTRUCTURE,
1289 * -FDT_ERR_TRUNCATED, standard meanings
1290 */
1291#ifndef SWIG /* Not available in Python */
1292int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
1293 const void *val, int len);
1294#endif
1295
1296/**
1297 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
1298 * @fdt: pointer to the device tree blob
1299 * @nodeoffset: offset of the node whose property to change
1300 * @name: name of the property to change
1301 * @val: 32-bit integer value to replace the property with
1302 *
1303 * fdt_setprop_inplace_u32() replaces the value of a given property
1304 * with the 32-bit integer value in val, converting val to big-endian
1305 * if necessary. This function cannot change the size of a property,
1306 * and so will only work if the property already exists and has length
1307 * 4.
1308 *
1309 * This function will alter only the bytes in the blob which contain
1310 * the given property value, and will not alter or move any other part
1311 * of the tree.
1312 *
1313 * returns:
1314 * 0, on success
1315 * -FDT_ERR_NOSPACE, if the property's length is not equal to 4
1316 * -FDT_ERR_NOTFOUND, node does not have the named property
1317 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1318 * -FDT_ERR_BADMAGIC,
1319 * -FDT_ERR_BADVERSION,
1320 * -FDT_ERR_BADSTATE,
1321 * -FDT_ERR_BADSTRUCTURE,
1322 * -FDT_ERR_TRUNCATED, standard meanings
1323 */
1324static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
1325 const char *name, uint32_t val)
1326{
1327 fdt32_t tmp = cpu_to_fdt32(val);
1328 return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1329}
1330
1331/**
1332 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
1333 * @fdt: pointer to the device tree blob
1334 * @nodeoffset: offset of the node whose property to change
1335 * @name: name of the property to change
1336 * @val: 64-bit integer value to replace the property with
1337 *
1338 * fdt_setprop_inplace_u64() replaces the value of a given property
1339 * with the 64-bit integer value in val, converting val to big-endian
1340 * if necessary. This function cannot change the size of a property,
1341 * and so will only work if the property already exists and has length
1342 * 8.
1343 *
1344 * This function will alter only the bytes in the blob which contain
1345 * the given property value, and will not alter or move any other part
1346 * of the tree.
1347 *
1348 * returns:
1349 * 0, on success
1350 * -FDT_ERR_NOSPACE, if the property's length is not equal to 8
1351 * -FDT_ERR_NOTFOUND, node does not have the named property
1352 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1353 * -FDT_ERR_BADMAGIC,
1354 * -FDT_ERR_BADVERSION,
1355 * -FDT_ERR_BADSTATE,
1356 * -FDT_ERR_BADSTRUCTURE,
1357 * -FDT_ERR_TRUNCATED, standard meanings
1358 */
1359static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
1360 const char *name, uint64_t val)
1361{
1362 fdt64_t tmp = cpu_to_fdt64(val);
1363 return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1364}
1365
1366/**
1367 * fdt_setprop_inplace_cell - change the value of a single-cell property
1368 * @fdt: pointer to the device tree blob
1369 * @nodeoffset: offset of the node containing the property
1370 * @name: name of the property to change the value of
1371 * @val: new value of the 32-bit cell
1372 *
1373 * This is an alternative name for fdt_setprop_inplace_u32()
1374 * Return: 0 on success, negative libfdt error number otherwise.
1375 */
1376static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
1377 const char *name, uint32_t val)
1378{
1379 return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
1380}
1381
1382/**
1383 * fdt_nop_property - replace a property with nop tags
1384 * @fdt: pointer to the device tree blob
1385 * @nodeoffset: offset of the node whose property to nop
1386 * @name: name of the property to nop
1387 *
1388 * fdt_nop_property() will replace a given property's representation
1389 * in the blob with FDT_NOP tags, effectively removing it from the
1390 * tree.
1391 *
1392 * This function will alter only the bytes in the blob which contain
1393 * the property, and will not alter or move any other part of the
1394 * tree.
1395 *
1396 * returns:
1397 * 0, on success
1398 * -FDT_ERR_NOTFOUND, node does not have the named property
1399 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1400 * -FDT_ERR_BADMAGIC,
1401 * -FDT_ERR_BADVERSION,
1402 * -FDT_ERR_BADSTATE,
1403 * -FDT_ERR_BADSTRUCTURE,
1404 * -FDT_ERR_TRUNCATED, standard meanings
1405 */
1406int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
1407
1408/**
1409 * fdt_nop_node - replace a node (subtree) with nop tags
1410 * @fdt: pointer to the device tree blob
1411 * @nodeoffset: offset of the node to nop
1412 *
1413 * fdt_nop_node() will replace a given node's representation in the
1414 * blob, including all its subnodes, if any, with FDT_NOP tags,
1415 * effectively removing it from the tree.
1416 *
1417 * This function will alter only the bytes in the blob which contain
1418 * the node and its properties and subnodes, and will not alter or
1419 * move any other part of the tree.
1420 *
1421 * returns:
1422 * 0, on success
1423 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1424 * -FDT_ERR_BADMAGIC,
1425 * -FDT_ERR_BADVERSION,
1426 * -FDT_ERR_BADSTATE,
1427 * -FDT_ERR_BADSTRUCTURE,
1428 * -FDT_ERR_TRUNCATED, standard meanings
1429 */
1430int fdt_nop_node(void *fdt, int nodeoffset);
1431
1432/**********************************************************************/
1433/* Sequential write functions */
1434/**********************************************************************/
1435
1436/* fdt_create_with_flags flags */
1437#define FDT_CREATE_FLAG_NO_NAME_DEDUP 0x1
1438 /* FDT_CREATE_FLAG_NO_NAME_DEDUP: Do not try to de-duplicate property
1439 * names in the fdt. This can result in faster creation times, but
1440 * a larger fdt. */
1441
1442#define FDT_CREATE_FLAGS_ALL (FDT_CREATE_FLAG_NO_NAME_DEDUP)
1443
1444/**
1445 * fdt_create_with_flags - begin creation of a new fdt
1446 * @buf: pointer to memory allocated where fdt will be created
1447 * @bufsize: size of the memory space at fdt
1448 * @flags: a valid combination of FDT_CREATE_FLAG_ flags, or 0.
1449 *
1450 * fdt_create_with_flags() begins the process of creating a new fdt with
1451 * the sequential write interface.
1452 *
1453 * fdt creation process must end with fdt_finished() to produce a valid fdt.
1454 *
1455 * returns:
1456 * 0, on success
1457 * -FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1458 * -FDT_ERR_BADFLAGS, flags is not valid
1459 */
1460int fdt_create_with_flags(void *buf, int bufsize, uint32_t flags);
1461
1462/**
1463 * fdt_create - begin creation of a new fdt
1464 * @buf: pointer to memory allocated where fdt will be created
1465 * @bufsize: size of the memory space at fdt
1466 *
1467 * fdt_create() is equivalent to fdt_create_with_flags() with flags=0.
1468 *
1469 * returns:
1470 * 0, on success
1471 * -FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1472 */
1473int fdt_create(void *buf, int bufsize);
1474
1475int fdt_resize(void *fdt, void *buf, int bufsize);
1476int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
1477int fdt_finish_reservemap(void *fdt);
1478int fdt_begin_node(void *fdt, const char *name);
1479int fdt_property(void *fdt, const char *name, const void *val, int len);
1480static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
1481{
1482 fdt32_t tmp = cpu_to_fdt32(val);
1483 return fdt_property(fdt, name, &tmp, sizeof(tmp));
1484}
1485static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
1486{
1487 fdt64_t tmp = cpu_to_fdt64(val);
1488 return fdt_property(fdt, name, &tmp, sizeof(tmp));
1489}
1490
1491#ifndef SWIG /* Not available in Python */
1492static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
1493{
1494 return fdt_property_u32(fdt, name, val);
1495}
1496#endif
1497
1498/**
1499 * fdt_property_placeholder - add a new property and return a ptr to its value
1500 *
1501 * @fdt: pointer to the device tree blob
1502 * @name: name of property to add
1503 * @len: length of property value in bytes
1504 * @valp: returns a pointer to where where the value should be placed
1505 *
1506 * returns:
1507 * 0, on success
1508 * -FDT_ERR_BADMAGIC,
1509 * -FDT_ERR_NOSPACE, standard meanings
1510 */
1511int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp);
1512
1513#define fdt_property_string(fdt, name, str) \
1514 fdt_property(fdt, name, str, strlen(str)+1)
1515int fdt_end_node(void *fdt);
1516int fdt_finish(void *fdt);
1517
1518/**********************************************************************/
1519/* Read-write functions */
1520/**********************************************************************/
1521
1522int fdt_create_empty_tree(void *buf, int bufsize);
1523int fdt_open_into(const void *fdt, void *buf, int bufsize);
1524int fdt_pack(void *fdt);
1525
1526/**
1527 * fdt_add_mem_rsv - add one memory reserve map entry
1528 * @fdt: pointer to the device tree blob
1529 * @address: 64-bit start address of the reserve map entry
1530 * @size: 64-bit size of the reserved region
1531 *
1532 * Adds a reserve map entry to the given blob reserving a region at
1533 * address address of length size.
1534 *
1535 * This function will insert data into the reserve map and will
1536 * therefore change the indexes of some entries in the table.
1537 *
1538 * returns:
1539 * 0, on success
1540 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1541 * contain the new reservation entry
1542 * -FDT_ERR_BADMAGIC,
1543 * -FDT_ERR_BADVERSION,
1544 * -FDT_ERR_BADSTATE,
1545 * -FDT_ERR_BADSTRUCTURE,
1546 * -FDT_ERR_BADLAYOUT,
1547 * -FDT_ERR_TRUNCATED, standard meanings
1548 */
1549int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
1550
1551/**
1552 * fdt_del_mem_rsv - remove a memory reserve map entry
1553 * @fdt: pointer to the device tree blob
1554 * @n: entry to remove
1555 *
1556 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
1557 * the blob.
1558 *
1559 * This function will delete data from the reservation table and will
1560 * therefore change the indexes of some entries in the table.
1561 *
1562 * returns:
1563 * 0, on success
1564 * -FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
1565 * are less than n+1 reserve map entries)
1566 * -FDT_ERR_BADMAGIC,
1567 * -FDT_ERR_BADVERSION,
1568 * -FDT_ERR_BADSTATE,
1569 * -FDT_ERR_BADSTRUCTURE,
1570 * -FDT_ERR_BADLAYOUT,
1571 * -FDT_ERR_TRUNCATED, standard meanings
1572 */
1573int fdt_del_mem_rsv(void *fdt, int n);
1574
1575/**
1576 * fdt_set_name - change the name of a given node
1577 * @fdt: pointer to the device tree blob
1578 * @nodeoffset: structure block offset of a node
1579 * @name: name to give the node
1580 *
1581 * fdt_set_name() replaces the name (including unit address, if any)
1582 * of the given node with the given string. NOTE: this function can't
1583 * efficiently check if the new name is unique amongst the given
1584 * node's siblings; results are undefined if this function is invoked
1585 * with a name equal to one of the given node's siblings.
1586 *
1587 * This function may insert or delete data from the blob, and will
1588 * therefore change the offsets of some existing nodes.
1589 *
1590 * returns:
1591 * 0, on success
1592 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob
1593 * to contain the new name
1594 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1595 * -FDT_ERR_BADMAGIC,
1596 * -FDT_ERR_BADVERSION,
1597 * -FDT_ERR_BADSTATE, standard meanings
1598 */
1599int fdt_set_name(void *fdt, int nodeoffset, const char *name);
1600
1601/**
1602 * fdt_setprop - create or change a property
1603 * @fdt: pointer to the device tree blob
1604 * @nodeoffset: offset of the node whose property to change
1605 * @name: name of the property to change
1606 * @val: pointer to data to set the property value to
1607 * @len: length of the property value
1608 *
1609 * fdt_setprop() sets the value of the named property in the given
1610 * node to the given value and length, creating the property if it
1611 * does not already exist.
1612 *
1613 * This function may insert or delete data from the blob, and will
1614 * therefore change the offsets of some existing nodes.
1615 *
1616 * returns:
1617 * 0, on success
1618 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1619 * contain the new property value
1620 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1621 * -FDT_ERR_BADLAYOUT,
1622 * -FDT_ERR_BADMAGIC,
1623 * -FDT_ERR_BADVERSION,
1624 * -FDT_ERR_BADSTATE,
1625 * -FDT_ERR_BADSTRUCTURE,
1626 * -FDT_ERR_BADLAYOUT,
1627 * -FDT_ERR_TRUNCATED, standard meanings
1628 */
1629int fdt_setprop(void *fdt, int nodeoffset, const char *name,
1630 const void *val, int len);
1631
1632/**
1633 * fdt_setprop_placeholder - allocate space for a property
1634 * @fdt: pointer to the device tree blob
1635 * @nodeoffset: offset of the node whose property to change
1636 * @name: name of the property to change
1637 * @len: length of the property value
1638 * @prop_data: return pointer to property data
1639 *
1640 * fdt_setprop_placeholer() allocates the named property in the given node.
1641 * If the property exists it is resized. In either case a pointer to the
1642 * property data is returned.
1643 *
1644 * This function may insert or delete data from the blob, and will
1645 * therefore change the offsets of some existing nodes.
1646 *
1647 * returns:
1648 * 0, on success
1649 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1650 * contain the new property value
1651 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1652 * -FDT_ERR_BADLAYOUT,
1653 * -FDT_ERR_BADMAGIC,
1654 * -FDT_ERR_BADVERSION,
1655 * -FDT_ERR_BADSTATE,
1656 * -FDT_ERR_BADSTRUCTURE,
1657 * -FDT_ERR_BADLAYOUT,
1658 * -FDT_ERR_TRUNCATED, standard meanings
1659 */
1660int fdt_setprop_placeholder(void *fdt, int nodeoffset, const char *name,
1661 int len, void **prop_data);
1662
1663/**
1664 * fdt_setprop_u32 - set a property to a 32-bit integer
1665 * @fdt: pointer to the device tree blob
1666 * @nodeoffset: offset of the node whose property to change
1667 * @name: name of the property to change
1668 * @val: 32-bit integer value for the property (native endian)
1669 *
1670 * fdt_setprop_u32() sets the value of the named property in the given
1671 * node to the given 32-bit integer value (converting to big-endian if
1672 * necessary), or creates a new property with that value if it does
1673 * not already exist.
1674 *
1675 * This function may insert or delete data from the blob, and will
1676 * therefore change the offsets of some existing nodes.
1677 *
1678 * returns:
1679 * 0, on success
1680 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1681 * contain the new property value
1682 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1683 * -FDT_ERR_BADLAYOUT,
1684 * -FDT_ERR_BADMAGIC,
1685 * -FDT_ERR_BADVERSION,
1686 * -FDT_ERR_BADSTATE,
1687 * -FDT_ERR_BADSTRUCTURE,
1688 * -FDT_ERR_BADLAYOUT,
1689 * -FDT_ERR_TRUNCATED, standard meanings
1690 */
1691static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
1692 uint32_t val)
1693{
1694 fdt32_t tmp = cpu_to_fdt32(val);
1695 return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1696}
1697
1698/**
1699 * fdt_setprop_u64 - set a property to a 64-bit integer
1700 * @fdt: pointer to the device tree blob
1701 * @nodeoffset: offset of the node whose property to change
1702 * @name: name of the property to change
1703 * @val: 64-bit integer value for the property (native endian)
1704 *
1705 * fdt_setprop_u64() sets the value of the named property in the given
1706 * node to the given 64-bit integer value (converting to big-endian if
1707 * necessary), or creates a new property with that value if it does
1708 * not already exist.
1709 *
1710 * This function may insert or delete data from the blob, and will
1711 * therefore change the offsets of some existing nodes.
1712 *
1713 * returns:
1714 * 0, on success
1715 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1716 * contain the new property value
1717 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1718 * -FDT_ERR_BADLAYOUT,
1719 * -FDT_ERR_BADMAGIC,
1720 * -FDT_ERR_BADVERSION,
1721 * -FDT_ERR_BADSTATE,
1722 * -FDT_ERR_BADSTRUCTURE,
1723 * -FDT_ERR_BADLAYOUT,
1724 * -FDT_ERR_TRUNCATED, standard meanings
1725 */
1726static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
1727 uint64_t val)
1728{
1729 fdt64_t tmp = cpu_to_fdt64(val);
1730 return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1731}
1732
1733/**
1734 * fdt_setprop_cell - set a property to a single cell value
1735 * @fdt: pointer to the device tree blob
1736 * @nodeoffset: offset of the node whose property to change
1737 * @name: name of the property to change
1738 * @val: 32-bit integer value for the property (native endian)
1739 *
1740 * This is an alternative name for fdt_setprop_u32()
1741 *
1742 * Return: 0 on success, negative libfdt error value otherwise.
1743 */
1744static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
1745 uint32_t val)
1746{
1747 return fdt_setprop_u32(fdt, nodeoffset, name, val);
1748}
1749
1750/**
1751 * fdt_setprop_string - set a property to a string value
1752 * @fdt: pointer to the device tree blob
1753 * @nodeoffset: offset of the node whose property to change
1754 * @name: name of the property to change
1755 * @str: string value for the property
1756 *
1757 * fdt_setprop_string() sets the value of the named property in the
1758 * given node to the given string value (using the length of the
1759 * string to determine the new length of the property), or creates a
1760 * new property with that value if it does not already exist.
1761 *
1762 * This function may insert or delete data from the blob, and will
1763 * therefore change the offsets of some existing nodes.
1764 *
1765 * returns:
1766 * 0, on success
1767 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1768 * contain the new property value
1769 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1770 * -FDT_ERR_BADLAYOUT,
1771 * -FDT_ERR_BADMAGIC,
1772 * -FDT_ERR_BADVERSION,
1773 * -FDT_ERR_BADSTATE,
1774 * -FDT_ERR_BADSTRUCTURE,
1775 * -FDT_ERR_BADLAYOUT,
1776 * -FDT_ERR_TRUNCATED, standard meanings
1777 */
1778#define fdt_setprop_string(fdt, nodeoffset, name, str) \
1779 fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1780
1781
1782/**
1783 * fdt_setprop_empty - set a property to an empty value
1784 * @fdt: pointer to the device tree blob
1785 * @nodeoffset: offset of the node whose property to change
1786 * @name: name of the property to change
1787 *
1788 * fdt_setprop_empty() sets the value of the named property in the
1789 * given node to an empty (zero length) value, or creates a new empty
1790 * property if it does not already exist.
1791 *
1792 * This function may insert or delete data from the blob, and will
1793 * therefore change the offsets of some existing nodes.
1794 *
1795 * returns:
1796 * 0, on success
1797 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1798 * contain the new property value
1799 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1800 * -FDT_ERR_BADLAYOUT,
1801 * -FDT_ERR_BADMAGIC,
1802 * -FDT_ERR_BADVERSION,
1803 * -FDT_ERR_BADSTATE,
1804 * -FDT_ERR_BADSTRUCTURE,
1805 * -FDT_ERR_BADLAYOUT,
1806 * -FDT_ERR_TRUNCATED, standard meanings
1807 */
1808#define fdt_setprop_empty(fdt, nodeoffset, name) \
1809 fdt_setprop((fdt), (nodeoffset), (name), NULL, 0)
1810
1811/**
1812 * fdt_appendprop - append to or create a property
1813 * @fdt: pointer to the device tree blob
1814 * @nodeoffset: offset of the node whose property to change
1815 * @name: name of the property to append to
1816 * @val: pointer to data to append to the property value
1817 * @len: length of the data to append to the property value
1818 *
1819 * fdt_appendprop() appends the value to the named property in the
1820 * given node, creating the property if it does not already exist.
1821 *
1822 * This function may insert data into the blob, and will therefore
1823 * change the offsets of some existing nodes.
1824 *
1825 * returns:
1826 * 0, on success
1827 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1828 * contain the new property value
1829 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1830 * -FDT_ERR_BADLAYOUT,
1831 * -FDT_ERR_BADMAGIC,
1832 * -FDT_ERR_BADVERSION,
1833 * -FDT_ERR_BADSTATE,
1834 * -FDT_ERR_BADSTRUCTURE,
1835 * -FDT_ERR_BADLAYOUT,
1836 * -FDT_ERR_TRUNCATED, standard meanings
1837 */
1838int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
1839 const void *val, int len);
1840
1841/**
1842 * fdt_appendprop_u32 - append a 32-bit integer value to a property
1843 * @fdt: pointer to the device tree blob
1844 * @nodeoffset: offset of the node whose property to change
1845 * @name: name of the property to change
1846 * @val: 32-bit integer value to append to the property (native endian)
1847 *
1848 * fdt_appendprop_u32() appends the given 32-bit integer value
1849 * (converting to big-endian if necessary) to the value of the named
1850 * property in the given node, or creates a new property with that
1851 * value if it does not already exist.
1852 *
1853 * This function may insert data into the blob, and will therefore
1854 * change the offsets of some existing nodes.
1855 *
1856 * returns:
1857 * 0, on success
1858 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1859 * contain the new property value
1860 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1861 * -FDT_ERR_BADLAYOUT,
1862 * -FDT_ERR_BADMAGIC,
1863 * -FDT_ERR_BADVERSION,
1864 * -FDT_ERR_BADSTATE,
1865 * -FDT_ERR_BADSTRUCTURE,
1866 * -FDT_ERR_BADLAYOUT,
1867 * -FDT_ERR_TRUNCATED, standard meanings
1868 */
1869static inline int fdt_appendprop_u32(void *fdt, int nodeoffset,
1870 const char *name, uint32_t val)
1871{
1872 fdt32_t tmp = cpu_to_fdt32(val);
1873 return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1874}
1875
1876/**
1877 * fdt_appendprop_u64 - append a 64-bit integer value to a property
1878 * @fdt: pointer to the device tree blob
1879 * @nodeoffset: offset of the node whose property to change
1880 * @name: name of the property to change
1881 * @val: 64-bit integer value to append to the property (native endian)
1882 *
1883 * fdt_appendprop_u64() appends the given 64-bit integer value
1884 * (converting to big-endian if necessary) to the value of the named
1885 * property in the given node, or creates a new property with that
1886 * value if it does not already exist.
1887 *
1888 * This function may insert data into the blob, and will therefore
1889 * change the offsets of some existing nodes.
1890 *
1891 * returns:
1892 * 0, on success
1893 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1894 * contain the new property value
1895 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1896 * -FDT_ERR_BADLAYOUT,
1897 * -FDT_ERR_BADMAGIC,
1898 * -FDT_ERR_BADVERSION,
1899 * -FDT_ERR_BADSTATE,
1900 * -FDT_ERR_BADSTRUCTURE,
1901 * -FDT_ERR_BADLAYOUT,
1902 * -FDT_ERR_TRUNCATED, standard meanings
1903 */
1904static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
1905 const char *name, uint64_t val)
1906{
1907 fdt64_t tmp = cpu_to_fdt64(val);
1908 return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1909}
1910
1911/**
1912 * fdt_appendprop_cell - append a single cell value to a property
1913 * @fdt: pointer to the device tree blob
1914 * @nodeoffset: offset of the node whose property to change
1915 * @name: name of the property to change
1916 * @val: 32-bit integer value to append to the property (native endian)
1917 *
1918 * This is an alternative name for fdt_appendprop_u32()
1919 *
1920 * Return: 0 on success, negative libfdt error value otherwise.
1921 */
1922static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
1923 const char *name, uint32_t val)
1924{
1925 return fdt_appendprop_u32(fdt, nodeoffset, name, val);
1926}
1927
1928/**
1929 * fdt_appendprop_string - append a string to a property
1930 * @fdt: pointer to the device tree blob
1931 * @nodeoffset: offset of the node whose property to change
1932 * @name: name of the property to change
1933 * @str: string value to append to the property
1934 *
1935 * fdt_appendprop_string() appends the given string to the value of
1936 * the named property in the given node, or creates a new property
1937 * with that value if it does not already exist.
1938 *
1939 * This function may insert data into the blob, and will therefore
1940 * change the offsets of some existing nodes.
1941 *
1942 * returns:
1943 * 0, on success
1944 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1945 * contain the new property value
1946 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1947 * -FDT_ERR_BADLAYOUT,
1948 * -FDT_ERR_BADMAGIC,
1949 * -FDT_ERR_BADVERSION,
1950 * -FDT_ERR_BADSTATE,
1951 * -FDT_ERR_BADSTRUCTURE,
1952 * -FDT_ERR_BADLAYOUT,
1953 * -FDT_ERR_TRUNCATED, standard meanings
1954 */
1955#define fdt_appendprop_string(fdt, nodeoffset, name, str) \
1956 fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1957
1958/**
1959 * fdt_appendprop_addrrange - append a address range property
1960 * @fdt: pointer to the device tree blob
1961 * @parent: offset of the parent node
1962 * @nodeoffset: offset of the node to add a property at
1963 * @name: name of property
1964 * @addr: start address of a given range
1965 * @size: size of a given range
1966 *
1967 * fdt_appendprop_addrrange() appends an address range value (start
1968 * address and size) to the value of the named property in the given
1969 * node, or creates a new property with that value if it does not
1970 * already exist.
1971 * If "name" is not specified, a default "reg" is used.
1972 * Cell sizes are determined by parent's #address-cells and #size-cells.
1973 *
1974 * This function may insert data into the blob, and will therefore
1975 * change the offsets of some existing nodes.
1976 *
1977 * returns:
1978 * 0, on success
1979 * -FDT_ERR_BADLAYOUT,
1980 * -FDT_ERR_BADMAGIC,
1981 * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1982 * #address-cells property
1983 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1984 * -FDT_ERR_BADSTATE,
1985 * -FDT_ERR_BADSTRUCTURE,
1986 * -FDT_ERR_BADVERSION,
1987 * -FDT_ERR_BADVALUE, addr or size doesn't fit to respective cells size
1988 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1989 * contain a new property
1990 * -FDT_ERR_TRUNCATED, standard meanings
1991 */
1992int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
1993 const char *name, uint64_t addr, uint64_t size);
1994
1995/**
1996 * fdt_delprop - delete a property
1997 * @fdt: pointer to the device tree blob
1998 * @nodeoffset: offset of the node whose property to nop
1999 * @name: name of the property to nop
2000 *
2001 * fdt_del_property() will delete the given property.
2002 *
2003 * This function will delete data from the blob, and will therefore
2004 * change the offsets of some existing nodes.
2005 *
2006 * returns:
2007 * 0, on success
2008 * -FDT_ERR_NOTFOUND, node does not have the named property
2009 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2010 * -FDT_ERR_BADLAYOUT,
2011 * -FDT_ERR_BADMAGIC,
2012 * -FDT_ERR_BADVERSION,
2013 * -FDT_ERR_BADSTATE,
2014 * -FDT_ERR_BADSTRUCTURE,
2015 * -FDT_ERR_TRUNCATED, standard meanings
2016 */
2017int fdt_delprop(void *fdt, int nodeoffset, const char *name);
2018
2019/**
2020 * fdt_add_subnode_namelen - creates a new node based on substring
2021 * @fdt: pointer to the device tree blob
2022 * @parentoffset: structure block offset of a node
2023 * @name: name of the subnode to create
2024 * @namelen: number of characters of name to consider
2025 *
2026 * Identical to fdt_add_subnode(), but use only the first @namelen
2027 * characters of @name as the name of the new node. This is useful for
2028 * creating subnodes based on a portion of a larger string, such as a
2029 * full path.
2030 *
2031 * Return: structure block offset of the created subnode (>=0),
2032 * negative libfdt error value otherwise
2033 */
2034#ifndef SWIG /* Not available in Python */
2035int fdt_add_subnode_namelen(void *fdt, int parentoffset,
2036 const char *name, int namelen);
2037#endif
2038
2039/**
2040 * fdt_add_subnode - creates a new node
2041 * @fdt: pointer to the device tree blob
2042 * @parentoffset: structure block offset of a node
2043 * @name: name of the subnode to locate
2044 *
2045 * fdt_add_subnode() creates a new node as a subnode of the node at
2046 * structure block offset parentoffset, with the given name (which
2047 * should include the unit address, if any).
2048 *
2049 * This function will insert data into the blob, and will therefore
2050 * change the offsets of some existing nodes.
2051 *
2052 * returns:
2053 * structure block offset of the created nodeequested subnode (>=0), on
2054 * success
2055 * -FDT_ERR_NOTFOUND, if the requested subnode does not exist
2056 * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
2057 * tag
2058 * -FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
2059 * the given name
2060 * -FDT_ERR_NOSPACE, if there is insufficient free space in the
2061 * blob to contain the new node
2062 * -FDT_ERR_NOSPACE
2063 * -FDT_ERR_BADLAYOUT
2064 * -FDT_ERR_BADMAGIC,
2065 * -FDT_ERR_BADVERSION,
2066 * -FDT_ERR_BADSTATE,
2067 * -FDT_ERR_BADSTRUCTURE,
2068 * -FDT_ERR_TRUNCATED, standard meanings.
2069 */
2070int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
2071
2072/**
2073 * fdt_del_node - delete a node (subtree)
2074 * @fdt: pointer to the device tree blob
2075 * @nodeoffset: offset of the node to nop
2076 *
2077 * fdt_del_node() will remove the given node, including all its
2078 * subnodes if any, from the blob.
2079 *
2080 * This function will delete data from the blob, and will therefore
2081 * change the offsets of some existing nodes.
2082 *
2083 * returns:
2084 * 0, on success
2085 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2086 * -FDT_ERR_BADLAYOUT,
2087 * -FDT_ERR_BADMAGIC,
2088 * -FDT_ERR_BADVERSION,
2089 * -FDT_ERR_BADSTATE,
2090 * -FDT_ERR_BADSTRUCTURE,
2091 * -FDT_ERR_TRUNCATED, standard meanings
2092 */
2093int fdt_del_node(void *fdt, int nodeoffset);
2094
2095/**
2096 * fdt_overlay_apply - Applies a DT overlay on a base DT
2097 * @fdt: pointer to the base device tree blob
2098 * @fdto: pointer to the device tree overlay blob
2099 *
2100 * fdt_overlay_apply() will apply the given device tree overlay on the
2101 * given base device tree.
2102 *
2103 * Expect the base device tree to be modified, even if the function
2104 * returns an error.
2105 *
2106 * returns:
2107 * 0, on success
2108 * -FDT_ERR_NOSPACE, there's not enough space in the base device tree
2109 * -FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
2110 * properties in the base DT
2111 * -FDT_ERR_BADPHANDLE,
2112 * -FDT_ERR_BADOVERLAY,
2113 * -FDT_ERR_NOPHANDLES,
2114 * -FDT_ERR_INTERNAL,
2115 * -FDT_ERR_BADLAYOUT,
2116 * -FDT_ERR_BADMAGIC,
2117 * -FDT_ERR_BADOFFSET,
2118 * -FDT_ERR_BADPATH,
2119 * -FDT_ERR_BADVERSION,
2120 * -FDT_ERR_BADSTRUCTURE,
2121 * -FDT_ERR_BADSTATE,
2122 * -FDT_ERR_TRUNCATED, standard meanings
2123 */
2124int fdt_overlay_apply(void *fdt, void *fdto);
2125
2126/**
2127 * fdt_overlay_target_offset - retrieves the offset of a fragment's target
2128 * @fdt: Base device tree blob
2129 * @fdto: Device tree overlay blob
2130 * @fragment_offset: node offset of the fragment in the overlay
2131 * @pathp: pointer which receives the path of the target (or NULL)
2132 *
2133 * fdt_overlay_target_offset() retrieves the target offset in the base
2134 * device tree of a fragment, no matter how the actual targeting is
2135 * done (through a phandle or a path)
2136 *
2137 * returns:
2138 * the targeted node offset in the base device tree
2139 * Negative error code on error
2140 */
2141int fdt_overlay_target_offset(const void *fdt, const void *fdto,
2142 int fragment_offset, char const **pathp);
2143
2144/**********************************************************************/
2145/* Debugging / informational functions */
2146/**********************************************************************/
2147
2148const char *fdt_strerror(int errval);
2149
2150#ifdef __cplusplus
2151}
2152#endif
2153
2154#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 */