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
13 extern "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 */
120 const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen);
121 #endif
fdt_offset_ptr_w(void * fdt,int offset,int checklen)122 static 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
127 uint32_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 */
fdt16_ld(const fdt16_t * p)134 static 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
fdt32_ld(const fdt32_t * p)141 static 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
fdt32_st(void * property,uint32_t value)151 static 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
fdt64_ld(const fdt64_t * p)161 static 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
fdt64_st(void * property,uint64_t value)175 static 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
193 int 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 */
202 int 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 */
215 int 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 }
266 fdt_set_hdr_(magic);
267 fdt_set_hdr_(totalsize);
268 fdt_set_hdr_(off_dt_struct);
269 fdt_set_hdr_(off_dt_strings);
270 fdt_set_hdr_(off_mem_rsvmap);
271 fdt_set_hdr_(version);
272 fdt_set_hdr_(last_comp_version);
273 fdt_set_hdr_(boot_cpuid_phys);
274 fdt_set_hdr_(size_dt_strings);
275 fdt_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 */
284 size_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 */
292 size_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 */
310 int 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 */
331 int fdt_move(const void *fdt, void *buf, int bufsize);
332
333 /**********************************************************************/
334 /* Read-only functions */
335 /**********************************************************************/
336
337 int 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 */
353 const 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 */
367 const 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 */
381 int 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 */
fdt_get_max_phandle(const void * fdt)398 static 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 */
422 int 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 */
435 int 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 */
454 int 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 */
471 int 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 */
498 int 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 */
512 int 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 */
538 int 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 */
563 const 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 */
583 int 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 */
604 int 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 */
660 const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
661 int offset,
662 int *lenp);
663
664 /**
665 * fdt_get_property_namelen - find a property based on substring
666 * @fdt: pointer to the device tree blob
667 * @nodeoffset: offset of the node whose property to find
668 * @name: name of the property to find
669 * @namelen: number of characters of name to consider
670 * @lenp: pointer to an integer variable (will be overwritten) or NULL
671 *
672 * Identical to fdt_get_property(), but only examine the first namelen
673 * characters of name for matching the property name.
674 *
675 * Return: pointer to the structure representing the property, or NULL
676 * if not found
677 */
678 #ifndef SWIG /* Not available in Python */
679 const struct fdt_property *fdt_get_property_namelen(const void *fdt,
680 int nodeoffset,
681 const char *name,
682 int namelen, int *lenp);
683 #endif
684
685 /**
686 * fdt_get_property - find a given property in a given node
687 * @fdt: pointer to the device tree blob
688 * @nodeoffset: offset of the node whose property to find
689 * @name: name of the property to find
690 * @lenp: pointer to an integer variable (will be overwritten) or NULL
691 *
692 * fdt_get_property() retrieves a pointer to the fdt_property
693 * structure within the device tree blob corresponding to the property
694 * named 'name' of the node at offset nodeoffset. If lenp is
695 * non-NULL, the length of the property value is also returned, in the
696 * integer pointed to by lenp.
697 *
698 * returns:
699 * pointer to the structure representing the property
700 * if lenp is non-NULL, *lenp contains the length of the property
701 * value (>=0)
702 * NULL, on error
703 * if lenp is non-NULL, *lenp contains an error code (<0):
704 * -FDT_ERR_NOTFOUND, node does not have named property
705 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
706 * tag
707 * -FDT_ERR_BADMAGIC,
708 * -FDT_ERR_BADVERSION,
709 * -FDT_ERR_BADSTATE,
710 * -FDT_ERR_BADSTRUCTURE,
711 * -FDT_ERR_TRUNCATED, standard meanings
712 */
713 const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
714 const char *name, int *lenp);
fdt_get_property_w(void * fdt,int nodeoffset,const char * name,int * lenp)715 static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
716 const char *name,
717 int *lenp)
718 {
719 return (struct fdt_property *)(uintptr_t)
720 fdt_get_property(fdt, nodeoffset, name, lenp);
721 }
722
723 /**
724 * fdt_getprop_by_offset - retrieve the value of a property at a given offset
725 * @fdt: pointer to the device tree blob
726 * @offset: offset of the property to read
727 * @namep: pointer to a string variable (will be overwritten) or NULL
728 * @lenp: pointer to an integer variable (will be overwritten) or NULL
729 *
730 * fdt_getprop_by_offset() retrieves a pointer to the value of the
731 * property at structure block offset 'offset' (this will be a pointer
732 * to within the device blob itself, not a copy of the value). If
733 * lenp is non-NULL, the length of the property value is also
734 * returned, in the integer pointed to by lenp. If namep is non-NULL,
735 * the property's namne will also be returned in the char * pointed to
736 * by namep (this will be a pointer to within the device tree's string
737 * block, not a new copy of the name).
738 *
739 * returns:
740 * pointer to the property's value
741 * if lenp is non-NULL, *lenp contains the length of the property
742 * value (>=0)
743 * if namep is non-NULL *namep contiains a pointer to the property
744 * name.
745 * NULL, on error
746 * if lenp is non-NULL, *lenp contains an error code (<0):
747 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
748 * -FDT_ERR_BADMAGIC,
749 * -FDT_ERR_BADVERSION,
750 * -FDT_ERR_BADSTATE,
751 * -FDT_ERR_BADSTRUCTURE,
752 * -FDT_ERR_TRUNCATED, standard meanings
753 */
754 #ifndef SWIG /* This function is not useful in Python */
755 const void *fdt_getprop_by_offset(const void *fdt, int offset,
756 const char **namep, int *lenp);
757 #endif
758
759 /**
760 * fdt_getprop_namelen - get property value based on substring
761 * @fdt: pointer to the device tree blob
762 * @nodeoffset: offset of the node whose property to find
763 * @name: name of the property to find
764 * @namelen: number of characters of name to consider
765 * @lenp: pointer to an integer variable (will be overwritten) or NULL
766 *
767 * Identical to fdt_getprop(), but only examine the first namelen
768 * characters of name for matching the property name.
769 *
770 * Return: pointer to the property's value or NULL on error
771 */
772 #ifndef SWIG /* Not available in Python */
773 const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
774 const char *name, int namelen, int *lenp);
fdt_getprop_namelen_w(void * fdt,int nodeoffset,const char * name,int namelen,int * lenp)775 static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset,
776 const char *name, int namelen,
777 int *lenp)
778 {
779 return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name,
780 namelen, lenp);
781 }
782 #endif
783
784 /**
785 * fdt_getprop - retrieve the value of a given property
786 * @fdt: pointer to the device tree blob
787 * @nodeoffset: offset of the node whose property to find
788 * @name: name of the property to find
789 * @lenp: pointer to an integer variable (will be overwritten) or NULL
790 *
791 * fdt_getprop() retrieves a pointer to the value of the property
792 * named @name of the node at offset @nodeoffset (this will be a
793 * pointer to within the device blob itself, not a copy of the value).
794 * If @lenp is non-NULL, the length of the property value is also
795 * returned, in the integer pointed to by @lenp.
796 *
797 * returns:
798 * pointer to the property's value
799 * if lenp is non-NULL, *lenp contains the length of the property
800 * value (>=0)
801 * NULL, on error
802 * if lenp is non-NULL, *lenp contains an error code (<0):
803 * -FDT_ERR_NOTFOUND, node does not have named property
804 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
805 * tag
806 * -FDT_ERR_BADMAGIC,
807 * -FDT_ERR_BADVERSION,
808 * -FDT_ERR_BADSTATE,
809 * -FDT_ERR_BADSTRUCTURE,
810 * -FDT_ERR_TRUNCATED, standard meanings
811 */
812 const void *fdt_getprop(const void *fdt, int nodeoffset,
813 const char *name, int *lenp);
fdt_getprop_w(void * fdt,int nodeoffset,const char * name,int * lenp)814 static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
815 const char *name, int *lenp)
816 {
817 return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
818 }
819
820 /**
821 * fdt_get_phandle - retrieve the phandle of a given node
822 * @fdt: pointer to the device tree blob
823 * @nodeoffset: structure block offset of the node
824 *
825 * fdt_get_phandle() retrieves the phandle of the device tree node at
826 * structure block offset nodeoffset.
827 *
828 * returns:
829 * the phandle of the node at nodeoffset, on success (!= 0, != -1)
830 * 0, if the node has no phandle, or another error occurs
831 */
832 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
833
834 /**
835 * fdt_get_alias_namelen - get alias based on substring
836 * @fdt: pointer to the device tree blob
837 * @name: name of the alias th look up
838 * @namelen: number of characters of name to consider
839 *
840 * Identical to fdt_get_alias(), but only examine the first @namelen
841 * characters of @name for matching the alias name.
842 *
843 * Return: a pointer to the expansion of the alias named @name, if it exists,
844 * NULL otherwise
845 */
846 #ifndef SWIG /* Not available in Python */
847 const char *fdt_get_alias_namelen(const void *fdt,
848 const char *name, int namelen);
849 #endif
850
851 /**
852 * fdt_get_alias - retrieve the path referenced by a given alias
853 * @fdt: pointer to the device tree blob
854 * @name: name of the alias th look up
855 *
856 * fdt_get_alias() retrieves the value of a given alias. That is, the
857 * value of the property named @name in the node /aliases.
858 *
859 * returns:
860 * a pointer to the expansion of the alias named 'name', if it exists
861 * NULL, if the given alias or the /aliases node does not exist
862 */
863 const char *fdt_get_alias(const void *fdt, const char *name);
864
865 /**
866 * fdt_get_path - determine the full path of a node
867 * @fdt: pointer to the device tree blob
868 * @nodeoffset: offset of the node whose path to find
869 * @buf: character buffer to contain the returned path (will be overwritten)
870 * @buflen: size of the character buffer at buf
871 *
872 * fdt_get_path() computes the full path of the node at offset
873 * nodeoffset, and records that path in the buffer at buf.
874 *
875 * NOTE: This function is expensive, as it must scan the device tree
876 * structure from the start to nodeoffset.
877 *
878 * returns:
879 * 0, on success
880 * buf contains the absolute path of the node at
881 * nodeoffset, as a NUL-terminated string.
882 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
883 * -FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
884 * characters and will not fit in the given buffer.
885 * -FDT_ERR_BADMAGIC,
886 * -FDT_ERR_BADVERSION,
887 * -FDT_ERR_BADSTATE,
888 * -FDT_ERR_BADSTRUCTURE, standard meanings
889 */
890 int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
891
892 /**
893 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
894 * @fdt: pointer to the device tree blob
895 * @nodeoffset: offset of the node whose parent to find
896 * @supernodedepth: depth of the ancestor to find
897 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
898 *
899 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
900 * at a specific depth from the root (where the root itself has depth
901 * 0, its immediate subnodes depth 1 and so forth). So
902 * fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
903 * will always return 0, the offset of the root node. If the node at
904 * nodeoffset has depth D, then:
905 * fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
906 * will return nodeoffset itself.
907 *
908 * NOTE: This function is expensive, as it must scan the device tree
909 * structure from the start to nodeoffset.
910 *
911 * returns:
912 * structure block offset of the node at node offset's ancestor
913 * of depth supernodedepth (>=0), on success
914 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
915 * -FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of
916 * nodeoffset
917 * -FDT_ERR_BADMAGIC,
918 * -FDT_ERR_BADVERSION,
919 * -FDT_ERR_BADSTATE,
920 * -FDT_ERR_BADSTRUCTURE, standard meanings
921 */
922 int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
923 int supernodedepth, int *nodedepth);
924
925 /**
926 * fdt_node_depth - find the depth of a given node
927 * @fdt: pointer to the device tree blob
928 * @nodeoffset: offset of the node whose parent to find
929 *
930 * fdt_node_depth() finds the depth of a given node. The root node
931 * has depth 0, its immediate subnodes depth 1 and so forth.
932 *
933 * NOTE: This function is expensive, as it must scan the device tree
934 * structure from the start to nodeoffset.
935 *
936 * returns:
937 * depth of the node at nodeoffset (>=0), on success
938 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
939 * -FDT_ERR_BADMAGIC,
940 * -FDT_ERR_BADVERSION,
941 * -FDT_ERR_BADSTATE,
942 * -FDT_ERR_BADSTRUCTURE, standard meanings
943 */
944 int fdt_node_depth(const void *fdt, int nodeoffset);
945
946 /**
947 * fdt_parent_offset - find the parent of a given node
948 * @fdt: pointer to the device tree blob
949 * @nodeoffset: offset of the node whose parent to find
950 *
951 * fdt_parent_offset() locates the parent node of a given node (that
952 * is, it finds the offset of the node which contains the node at
953 * nodeoffset as a subnode).
954 *
955 * NOTE: This function is expensive, as it must scan the device tree
956 * structure from the start to nodeoffset, *twice*.
957 *
958 * returns:
959 * structure block offset of the parent of the node at nodeoffset
960 * (>=0), on success
961 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
962 * -FDT_ERR_BADMAGIC,
963 * -FDT_ERR_BADVERSION,
964 * -FDT_ERR_BADSTATE,
965 * -FDT_ERR_BADSTRUCTURE, standard meanings
966 */
967 int fdt_parent_offset(const void *fdt, int nodeoffset);
968
969 /**
970 * fdt_node_offset_by_prop_value - find nodes with a given property value
971 * @fdt: pointer to the device tree blob
972 * @startoffset: only find nodes after this offset
973 * @propname: property name to check
974 * @propval: property value to search for
975 * @proplen: length of the value in propval
976 *
977 * fdt_node_offset_by_prop_value() returns the offset of the first
978 * node after startoffset, which has a property named propname whose
979 * value is of length proplen and has value equal to propval; or if
980 * startoffset is -1, the very first such node in the tree.
981 *
982 * To iterate through all nodes matching the criterion, the following
983 * idiom can be used:
984 * offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
985 * propval, proplen);
986 * while (offset != -FDT_ERR_NOTFOUND) {
987 * // other code here
988 * offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
989 * propval, proplen);
990 * }
991 *
992 * Note the -1 in the first call to the function, if 0 is used here
993 * instead, the function will never locate the root node, even if it
994 * matches the criterion.
995 *
996 * returns:
997 * structure block offset of the located node (>= 0, >startoffset),
998 * on success
999 * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
1000 * tree after startoffset
1001 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1002 * -FDT_ERR_BADMAGIC,
1003 * -FDT_ERR_BADVERSION,
1004 * -FDT_ERR_BADSTATE,
1005 * -FDT_ERR_BADSTRUCTURE, standard meanings
1006 */
1007 int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
1008 const char *propname,
1009 const void *propval, int proplen);
1010
1011 /**
1012 * fdt_node_offset_by_phandle - find the node with a given phandle
1013 * @fdt: pointer to the device tree blob
1014 * @phandle: phandle value
1015 *
1016 * fdt_node_offset_by_phandle() returns the offset of the node
1017 * which has the given phandle value. If there is more than one node
1018 * in the tree with the given phandle (an invalid tree), results are
1019 * undefined.
1020 *
1021 * returns:
1022 * structure block offset of the located node (>= 0), on success
1023 * -FDT_ERR_NOTFOUND, no node with that phandle exists
1024 * -FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
1025 * -FDT_ERR_BADMAGIC,
1026 * -FDT_ERR_BADVERSION,
1027 * -FDT_ERR_BADSTATE,
1028 * -FDT_ERR_BADSTRUCTURE, standard meanings
1029 */
1030 int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
1031
1032 /**
1033 * fdt_node_check_compatible - check a node's compatible property
1034 * @fdt: pointer to the device tree blob
1035 * @nodeoffset: offset of a tree node
1036 * @compatible: string to match against
1037 *
1038 * fdt_node_check_compatible() returns 0 if the given node contains a
1039 * @compatible property with the given string as one of its elements,
1040 * it returns non-zero otherwise, or on error.
1041 *
1042 * returns:
1043 * 0, if the node has a 'compatible' property listing the given string
1044 * 1, if the node has a 'compatible' property, but it does not list
1045 * the given string
1046 * -FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
1047 * -FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
1048 * -FDT_ERR_BADMAGIC,
1049 * -FDT_ERR_BADVERSION,
1050 * -FDT_ERR_BADSTATE,
1051 * -FDT_ERR_BADSTRUCTURE, standard meanings
1052 */
1053 int fdt_node_check_compatible(const void *fdt, int nodeoffset,
1054 const char *compatible);
1055
1056 /**
1057 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
1058 * @fdt: pointer to the device tree blob
1059 * @startoffset: only find nodes after this offset
1060 * @compatible: 'compatible' string to match against
1061 *
1062 * fdt_node_offset_by_compatible() returns the offset of the first
1063 * node after startoffset, which has a 'compatible' property which
1064 * lists the given compatible string; or if startoffset is -1, the
1065 * very first such node in the tree.
1066 *
1067 * To iterate through all nodes matching the criterion, the following
1068 * idiom can be used:
1069 * offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
1070 * while (offset != -FDT_ERR_NOTFOUND) {
1071 * // other code here
1072 * offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
1073 * }
1074 *
1075 * Note the -1 in the first call to the function, if 0 is used here
1076 * instead, the function will never locate the root node, even if it
1077 * matches the criterion.
1078 *
1079 * returns:
1080 * structure block offset of the located node (>= 0, >startoffset),
1081 * on success
1082 * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
1083 * tree after startoffset
1084 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1085 * -FDT_ERR_BADMAGIC,
1086 * -FDT_ERR_BADVERSION,
1087 * -FDT_ERR_BADSTATE,
1088 * -FDT_ERR_BADSTRUCTURE, standard meanings
1089 */
1090 int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
1091 const char *compatible);
1092
1093 /**
1094 * fdt_stringlist_contains - check a string list property for a string
1095 * @strlist: Property containing a list of strings to check
1096 * @listlen: Length of property
1097 * @str: String to search for
1098 *
1099 * This is a utility function provided for convenience. The list contains
1100 * one or more strings, each terminated by \0, as is found in a device tree
1101 * "compatible" property.
1102 *
1103 * Return: 1 if the string is found in the list, 0 not found, or invalid list
1104 */
1105 int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
1106
1107 /**
1108 * fdt_stringlist_count - count the number of strings in a string list
1109 * @fdt: pointer to the device tree blob
1110 * @nodeoffset: offset of a tree node
1111 * @property: name of the property containing the string list
1112 *
1113 * Return:
1114 * the number of strings in the given property
1115 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1116 * -FDT_ERR_NOTFOUND if the property does not exist
1117 */
1118 int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property);
1119
1120 /**
1121 * fdt_stringlist_search - find a string in a string list and return its index
1122 * @fdt: pointer to the device tree blob
1123 * @nodeoffset: offset of a tree node
1124 * @property: name of the property containing the string list
1125 * @string: string to look up in the string list
1126 *
1127 * Note that it is possible for this function to succeed on property values
1128 * that are not NUL-terminated. That's because the function will stop after
1129 * finding the first occurrence of @string. This can for example happen with
1130 * small-valued cell properties, such as #address-cells, when searching for
1131 * the empty string.
1132 *
1133 * return:
1134 * the index of the string in the list of strings
1135 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1136 * -FDT_ERR_NOTFOUND if the property does not exist or does not contain
1137 * the given string
1138 */
1139 int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
1140 const char *string);
1141
1142 /**
1143 * fdt_stringlist_get() - obtain the string at a given index in a string list
1144 * @fdt: pointer to the device tree blob
1145 * @nodeoffset: offset of a tree node
1146 * @property: name of the property containing the string list
1147 * @index: index of the string to return
1148 * @lenp: return location for the string length or an error code on failure
1149 *
1150 * Note that this will successfully extract strings from properties with
1151 * non-NUL-terminated values. For example on small-valued cell properties
1152 * this function will return the empty string.
1153 *
1154 * If non-NULL, the length of the string (on success) or a negative error-code
1155 * (on failure) will be stored in the integer pointer to by lenp.
1156 *
1157 * Return:
1158 * A pointer to the string at the given index in the string list or NULL on
1159 * failure. On success the length of the string will be stored in the memory
1160 * location pointed to by the lenp parameter, if non-NULL. On failure one of
1161 * the following negative error codes will be returned in the lenp parameter
1162 * (if non-NULL):
1163 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1164 * -FDT_ERR_NOTFOUND if the property does not exist
1165 */
1166 const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
1167 const char *property, int index,
1168 int *lenp);
1169
1170 /**********************************************************************/
1171 /* Read-only functions (addressing related) */
1172 /**********************************************************************/
1173
1174 /**
1175 * FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells
1176 *
1177 * This is the maximum value for #address-cells, #size-cells and
1178 * similar properties that will be processed by libfdt. IEE1275
1179 * requires that OF implementations handle values up to 4.
1180 * Implementations may support larger values, but in practice higher
1181 * values aren't used.
1182 */
1183 #define FDT_MAX_NCELLS 4
1184
1185 /**
1186 * fdt_address_cells - retrieve address size for a bus represented in the tree
1187 * @fdt: pointer to the device tree blob
1188 * @nodeoffset: offset of the node to find the address size for
1189 *
1190 * When the node has a valid #address-cells property, returns its value.
1191 *
1192 * returns:
1193 * 0 <= n < FDT_MAX_NCELLS, on success
1194 * 2, if the node has no #address-cells property
1195 * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1196 * #address-cells property
1197 * -FDT_ERR_BADMAGIC,
1198 * -FDT_ERR_BADVERSION,
1199 * -FDT_ERR_BADSTATE,
1200 * -FDT_ERR_BADSTRUCTURE,
1201 * -FDT_ERR_TRUNCATED, standard meanings
1202 */
1203 int fdt_address_cells(const void *fdt, int nodeoffset);
1204
1205 /**
1206 * fdt_size_cells - retrieve address range size for a bus represented in the
1207 * tree
1208 * @fdt: pointer to the device tree blob
1209 * @nodeoffset: offset of the node to find the address range size for
1210 *
1211 * When the node has a valid #size-cells property, returns its value.
1212 *
1213 * returns:
1214 * 0 <= n < FDT_MAX_NCELLS, on success
1215 * 1, if the node has no #size-cells property
1216 * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1217 * #size-cells property
1218 * -FDT_ERR_BADMAGIC,
1219 * -FDT_ERR_BADVERSION,
1220 * -FDT_ERR_BADSTATE,
1221 * -FDT_ERR_BADSTRUCTURE,
1222 * -FDT_ERR_TRUNCATED, standard meanings
1223 */
1224 int fdt_size_cells(const void *fdt, int nodeoffset);
1225
1226
1227 /**********************************************************************/
1228 /* Write-in-place functions */
1229 /**********************************************************************/
1230
1231 /**
1232 * fdt_setprop_inplace_namelen_partial - change a property's value,
1233 * but not its size
1234 * @fdt: pointer to the device tree blob
1235 * @nodeoffset: offset of the node whose property to change
1236 * @name: name of the property to change
1237 * @namelen: number of characters of name to consider
1238 * @idx: index of the property to change in the array
1239 * @val: pointer to data to replace the property value with
1240 * @len: length of the property value
1241 *
1242 * Identical to fdt_setprop_inplace(), but modifies the given property
1243 * starting from the given index, and using only the first characters
1244 * of the name. It is useful when you want to manipulate only one value of
1245 * an array and you have a string that doesn't end with \0.
1246 *
1247 * Return: 0 on success, negative libfdt error value otherwise
1248 */
1249 #ifndef SWIG /* Not available in Python */
1250 int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
1251 const char *name, int namelen,
1252 uint32_t idx, const void *val,
1253 int len);
1254 #endif
1255
1256 /**
1257 * fdt_setprop_inplace - change a property's value, but not its size
1258 * @fdt: pointer to the device tree blob
1259 * @nodeoffset: offset of the node whose property to change
1260 * @name: name of the property to change
1261 * @val: pointer to data to replace the property value with
1262 * @len: length of the property value
1263 *
1264 * fdt_setprop_inplace() replaces the value of a given property with
1265 * the data in val, of length len. This function cannot change the
1266 * size of a property, and so will only work if len is equal to the
1267 * current length of the property.
1268 *
1269 * This function will alter only the bytes in the blob which contain
1270 * the given property value, and will not alter or move any other part
1271 * of the tree.
1272 *
1273 * returns:
1274 * 0, on success
1275 * -FDT_ERR_NOSPACE, if len is not equal to the property's current length
1276 * -FDT_ERR_NOTFOUND, node does not have the named property
1277 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1278 * -FDT_ERR_BADMAGIC,
1279 * -FDT_ERR_BADVERSION,
1280 * -FDT_ERR_BADSTATE,
1281 * -FDT_ERR_BADSTRUCTURE,
1282 * -FDT_ERR_TRUNCATED, standard meanings
1283 */
1284 #ifndef SWIG /* Not available in Python */
1285 int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
1286 const void *val, int len);
1287 #endif
1288
1289 /**
1290 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
1291 * @fdt: pointer to the device tree blob
1292 * @nodeoffset: offset of the node whose property to change
1293 * @name: name of the property to change
1294 * @val: 32-bit integer value to replace the property with
1295 *
1296 * fdt_setprop_inplace_u32() replaces the value of a given property
1297 * with the 32-bit integer value in val, converting val to big-endian
1298 * if necessary. This function cannot change the size of a property,
1299 * and so will only work if the property already exists and has length
1300 * 4.
1301 *
1302 * This function will alter only the bytes in the blob which contain
1303 * the given property value, and will not alter or move any other part
1304 * of the tree.
1305 *
1306 * returns:
1307 * 0, on success
1308 * -FDT_ERR_NOSPACE, if the property's length is not equal to 4
1309 * -FDT_ERR_NOTFOUND, node does not have the named property
1310 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1311 * -FDT_ERR_BADMAGIC,
1312 * -FDT_ERR_BADVERSION,
1313 * -FDT_ERR_BADSTATE,
1314 * -FDT_ERR_BADSTRUCTURE,
1315 * -FDT_ERR_TRUNCATED, standard meanings
1316 */
fdt_setprop_inplace_u32(void * fdt,int nodeoffset,const char * name,uint32_t val)1317 static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
1318 const char *name, uint32_t val)
1319 {
1320 fdt32_t tmp = cpu_to_fdt32(val);
1321 return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1322 }
1323
1324 /**
1325 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
1326 * @fdt: pointer to the device tree blob
1327 * @nodeoffset: offset of the node whose property to change
1328 * @name: name of the property to change
1329 * @val: 64-bit integer value to replace the property with
1330 *
1331 * fdt_setprop_inplace_u64() replaces the value of a given property
1332 * with the 64-bit integer value in val, converting val to big-endian
1333 * if necessary. This function cannot change the size of a property,
1334 * and so will only work if the property already exists and has length
1335 * 8.
1336 *
1337 * This function will alter only the bytes in the blob which contain
1338 * the given property value, and will not alter or move any other part
1339 * of the tree.
1340 *
1341 * returns:
1342 * 0, on success
1343 * -FDT_ERR_NOSPACE, if the property's length is not equal to 8
1344 * -FDT_ERR_NOTFOUND, node does not have the named property
1345 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1346 * -FDT_ERR_BADMAGIC,
1347 * -FDT_ERR_BADVERSION,
1348 * -FDT_ERR_BADSTATE,
1349 * -FDT_ERR_BADSTRUCTURE,
1350 * -FDT_ERR_TRUNCATED, standard meanings
1351 */
fdt_setprop_inplace_u64(void * fdt,int nodeoffset,const char * name,uint64_t val)1352 static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
1353 const char *name, uint64_t val)
1354 {
1355 fdt64_t tmp = cpu_to_fdt64(val);
1356 return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1357 }
1358
1359 /**
1360 * fdt_setprop_inplace_cell - change the value of a single-cell property
1361 * @fdt: pointer to the device tree blob
1362 * @nodeoffset: offset of the node containing the property
1363 * @name: name of the property to change the value of
1364 * @val: new value of the 32-bit cell
1365 *
1366 * This is an alternative name for fdt_setprop_inplace_u32()
1367 * Return: 0 on success, negative libfdt error number otherwise.
1368 */
fdt_setprop_inplace_cell(void * fdt,int nodeoffset,const char * name,uint32_t val)1369 static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
1370 const char *name, uint32_t val)
1371 {
1372 return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
1373 }
1374
1375 /**
1376 * fdt_nop_property - replace a property with nop tags
1377 * @fdt: pointer to the device tree blob
1378 * @nodeoffset: offset of the node whose property to nop
1379 * @name: name of the property to nop
1380 *
1381 * fdt_nop_property() will replace a given property's representation
1382 * in the blob with FDT_NOP tags, effectively removing it from the
1383 * tree.
1384 *
1385 * This function will alter only the bytes in the blob which contain
1386 * the property, and will not alter or move any other part of the
1387 * tree.
1388 *
1389 * returns:
1390 * 0, on success
1391 * -FDT_ERR_NOTFOUND, node does not have the named property
1392 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1393 * -FDT_ERR_BADMAGIC,
1394 * -FDT_ERR_BADVERSION,
1395 * -FDT_ERR_BADSTATE,
1396 * -FDT_ERR_BADSTRUCTURE,
1397 * -FDT_ERR_TRUNCATED, standard meanings
1398 */
1399 int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
1400
1401 /**
1402 * fdt_nop_node - replace a node (subtree) with nop tags
1403 * @fdt: pointer to the device tree blob
1404 * @nodeoffset: offset of the node to nop
1405 *
1406 * fdt_nop_node() will replace a given node's representation in the
1407 * blob, including all its subnodes, if any, with FDT_NOP tags,
1408 * effectively removing it from the tree.
1409 *
1410 * This function will alter only the bytes in the blob which contain
1411 * the node and its properties and subnodes, and will not alter or
1412 * move any other part of the tree.
1413 *
1414 * returns:
1415 * 0, on success
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,
1420 * -FDT_ERR_BADSTRUCTURE,
1421 * -FDT_ERR_TRUNCATED, standard meanings
1422 */
1423 int fdt_nop_node(void *fdt, int nodeoffset);
1424
1425 /**********************************************************************/
1426 /* Sequential write functions */
1427 /**********************************************************************/
1428
1429 /* fdt_create_with_flags flags */
1430 #define FDT_CREATE_FLAG_NO_NAME_DEDUP 0x1
1431 /* FDT_CREATE_FLAG_NO_NAME_DEDUP: Do not try to de-duplicate property
1432 * names in the fdt. This can result in faster creation times, but
1433 * a larger fdt. */
1434
1435 #define FDT_CREATE_FLAGS_ALL (FDT_CREATE_FLAG_NO_NAME_DEDUP)
1436
1437 /**
1438 * fdt_create_with_flags - begin creation of a new fdt
1439 * @buf: pointer to memory allocated where fdt will be created
1440 * @bufsize: size of the memory space at fdt
1441 * @flags: a valid combination of FDT_CREATE_FLAG_ flags, or 0.
1442 *
1443 * fdt_create_with_flags() begins the process of creating a new fdt with
1444 * the sequential write interface.
1445 *
1446 * fdt creation process must end with fdt_finished() to produce a valid fdt.
1447 *
1448 * returns:
1449 * 0, on success
1450 * -FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1451 * -FDT_ERR_BADFLAGS, flags is not valid
1452 */
1453 int fdt_create_with_flags(void *buf, int bufsize, uint32_t flags);
1454
1455 /**
1456 * fdt_create - begin creation of a new fdt
1457 * @buf: pointer to memory allocated where fdt will be created
1458 * @bufsize: size of the memory space at fdt
1459 *
1460 * fdt_create() is equivalent to fdt_create_with_flags() with flags=0.
1461 *
1462 * returns:
1463 * 0, on success
1464 * -FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1465 */
1466 int fdt_create(void *buf, int bufsize);
1467
1468 int fdt_resize(void *fdt, void *buf, int bufsize);
1469 int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
1470 int fdt_finish_reservemap(void *fdt);
1471 int fdt_begin_node(void *fdt, const char *name);
1472 int fdt_property(void *fdt, const char *name, const void *val, int len);
fdt_property_u32(void * fdt,const char * name,uint32_t val)1473 static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
1474 {
1475 fdt32_t tmp = cpu_to_fdt32(val);
1476 return fdt_property(fdt, name, &tmp, sizeof(tmp));
1477 }
fdt_property_u64(void * fdt,const char * name,uint64_t val)1478 static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
1479 {
1480 fdt64_t tmp = cpu_to_fdt64(val);
1481 return fdt_property(fdt, name, &tmp, sizeof(tmp));
1482 }
1483
1484 #ifndef SWIG /* Not available in Python */
fdt_property_cell(void * fdt,const char * name,uint32_t val)1485 static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
1486 {
1487 return fdt_property_u32(fdt, name, val);
1488 }
1489 #endif
1490
1491 /**
1492 * fdt_property_placeholder - add a new property and return a ptr to its value
1493 *
1494 * @fdt: pointer to the device tree blob
1495 * @name: name of property to add
1496 * @len: length of property value in bytes
1497 * @valp: returns a pointer to where where the value should be placed
1498 *
1499 * returns:
1500 * 0, on success
1501 * -FDT_ERR_BADMAGIC,
1502 * -FDT_ERR_NOSPACE, standard meanings
1503 */
1504 int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp);
1505
1506 #define fdt_property_string(fdt, name, str) \
1507 fdt_property(fdt, name, str, strlen(str)+1)
1508 int fdt_end_node(void *fdt);
1509 int fdt_finish(void *fdt);
1510
1511 /**********************************************************************/
1512 /* Read-write functions */
1513 /**********************************************************************/
1514
1515 int fdt_create_empty_tree(void *buf, int bufsize);
1516 int fdt_open_into(const void *fdt, void *buf, int bufsize);
1517 int fdt_pack(void *fdt);
1518
1519 /**
1520 * fdt_add_mem_rsv - add one memory reserve map entry
1521 * @fdt: pointer to the device tree blob
1522 * @address: 64-bit start address of the reserve map entry
1523 * @size: 64-bit size of the reserved region
1524 *
1525 * Adds a reserve map entry to the given blob reserving a region at
1526 * address address of length size.
1527 *
1528 * This function will insert data into the reserve map and will
1529 * therefore change the indexes of some entries in the table.
1530 *
1531 * returns:
1532 * 0, on success
1533 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1534 * contain the new reservation entry
1535 * -FDT_ERR_BADMAGIC,
1536 * -FDT_ERR_BADVERSION,
1537 * -FDT_ERR_BADSTATE,
1538 * -FDT_ERR_BADSTRUCTURE,
1539 * -FDT_ERR_BADLAYOUT,
1540 * -FDT_ERR_TRUNCATED, standard meanings
1541 */
1542 int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
1543
1544 /**
1545 * fdt_del_mem_rsv - remove a memory reserve map entry
1546 * @fdt: pointer to the device tree blob
1547 * @n: entry to remove
1548 *
1549 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
1550 * the blob.
1551 *
1552 * This function will delete data from the reservation table and will
1553 * therefore change the indexes of some entries in the table.
1554 *
1555 * returns:
1556 * 0, on success
1557 * -FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
1558 * are less than n+1 reserve map entries)
1559 * -FDT_ERR_BADMAGIC,
1560 * -FDT_ERR_BADVERSION,
1561 * -FDT_ERR_BADSTATE,
1562 * -FDT_ERR_BADSTRUCTURE,
1563 * -FDT_ERR_BADLAYOUT,
1564 * -FDT_ERR_TRUNCATED, standard meanings
1565 */
1566 int fdt_del_mem_rsv(void *fdt, int n);
1567
1568 /**
1569 * fdt_set_name - change the name of a given node
1570 * @fdt: pointer to the device tree blob
1571 * @nodeoffset: structure block offset of a node
1572 * @name: name to give the node
1573 *
1574 * fdt_set_name() replaces the name (including unit address, if any)
1575 * of the given node with the given string. NOTE: this function can't
1576 * efficiently check if the new name is unique amongst the given
1577 * node's siblings; results are undefined if this function is invoked
1578 * with a name equal to one of the given node's siblings.
1579 *
1580 * This function may insert or delete data from the blob, and will
1581 * therefore change the offsets of some existing nodes.
1582 *
1583 * returns:
1584 * 0, on success
1585 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob
1586 * to contain the new name
1587 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1588 * -FDT_ERR_BADMAGIC,
1589 * -FDT_ERR_BADVERSION,
1590 * -FDT_ERR_BADSTATE, standard meanings
1591 */
1592 int fdt_set_name(void *fdt, int nodeoffset, const char *name);
1593
1594 /**
1595 * fdt_setprop - create or change a property
1596 * @fdt: pointer to the device tree blob
1597 * @nodeoffset: offset of the node whose property to change
1598 * @name: name of the property to change
1599 * @val: pointer to data to set the property value to
1600 * @len: length of the property value
1601 *
1602 * fdt_setprop() sets the value of the named property in the given
1603 * node to the given value and length, creating the property if it
1604 * does not already exist.
1605 *
1606 * This function may insert or delete data from the blob, and will
1607 * therefore change the offsets of some existing nodes.
1608 *
1609 * returns:
1610 * 0, on success
1611 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1612 * contain the new property value
1613 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1614 * -FDT_ERR_BADLAYOUT,
1615 * -FDT_ERR_BADMAGIC,
1616 * -FDT_ERR_BADVERSION,
1617 * -FDT_ERR_BADSTATE,
1618 * -FDT_ERR_BADSTRUCTURE,
1619 * -FDT_ERR_BADLAYOUT,
1620 * -FDT_ERR_TRUNCATED, standard meanings
1621 */
1622 int fdt_setprop(void *fdt, int nodeoffset, const char *name,
1623 const void *val, int len);
1624
1625 /**
1626 * fdt_setprop_placeholder - allocate space for a property
1627 * @fdt: pointer to the device tree blob
1628 * @nodeoffset: offset of the node whose property to change
1629 * @name: name of the property to change
1630 * @len: length of the property value
1631 * @prop_data: return pointer to property data
1632 *
1633 * fdt_setprop_placeholer() allocates the named property in the given node.
1634 * If the property exists it is resized. In either case a pointer to the
1635 * property data is returned.
1636 *
1637 * This function may insert or delete data from the blob, and will
1638 * therefore change the offsets of some existing nodes.
1639 *
1640 * returns:
1641 * 0, on success
1642 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1643 * contain the new property value
1644 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1645 * -FDT_ERR_BADLAYOUT,
1646 * -FDT_ERR_BADMAGIC,
1647 * -FDT_ERR_BADVERSION,
1648 * -FDT_ERR_BADSTATE,
1649 * -FDT_ERR_BADSTRUCTURE,
1650 * -FDT_ERR_BADLAYOUT,
1651 * -FDT_ERR_TRUNCATED, standard meanings
1652 */
1653 int fdt_setprop_placeholder(void *fdt, int nodeoffset, const char *name,
1654 int len, void **prop_data);
1655
1656 /**
1657 * fdt_setprop_u32 - set a property to a 32-bit integer
1658 * @fdt: pointer to the device tree blob
1659 * @nodeoffset: offset of the node whose property to change
1660 * @name: name of the property to change
1661 * @val: 32-bit integer value for the property (native endian)
1662 *
1663 * fdt_setprop_u32() sets the value of the named property in the given
1664 * node to the given 32-bit integer value (converting to big-endian if
1665 * necessary), or creates a new property with that value if it does
1666 * not already exist.
1667 *
1668 * This function may insert or delete data from the blob, and will
1669 * therefore change the offsets of some existing nodes.
1670 *
1671 * returns:
1672 * 0, on success
1673 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1674 * contain the new property value
1675 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1676 * -FDT_ERR_BADLAYOUT,
1677 * -FDT_ERR_BADMAGIC,
1678 * -FDT_ERR_BADVERSION,
1679 * -FDT_ERR_BADSTATE,
1680 * -FDT_ERR_BADSTRUCTURE,
1681 * -FDT_ERR_BADLAYOUT,
1682 * -FDT_ERR_TRUNCATED, standard meanings
1683 */
fdt_setprop_u32(void * fdt,int nodeoffset,const char * name,uint32_t val)1684 static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
1685 uint32_t val)
1686 {
1687 fdt32_t tmp = cpu_to_fdt32(val);
1688 return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1689 }
1690
1691 /**
1692 * fdt_setprop_u64 - set a property to a 64-bit integer
1693 * @fdt: pointer to the device tree blob
1694 * @nodeoffset: offset of the node whose property to change
1695 * @name: name of the property to change
1696 * @val: 64-bit integer value for the property (native endian)
1697 *
1698 * fdt_setprop_u64() sets the value of the named property in the given
1699 * node to the given 64-bit integer value (converting to big-endian if
1700 * necessary), or creates a new property with that value if it does
1701 * not already exist.
1702 *
1703 * This function may insert or delete data from the blob, and will
1704 * therefore change the offsets of some existing nodes.
1705 *
1706 * returns:
1707 * 0, on success
1708 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1709 * contain the new property value
1710 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1711 * -FDT_ERR_BADLAYOUT,
1712 * -FDT_ERR_BADMAGIC,
1713 * -FDT_ERR_BADVERSION,
1714 * -FDT_ERR_BADSTATE,
1715 * -FDT_ERR_BADSTRUCTURE,
1716 * -FDT_ERR_BADLAYOUT,
1717 * -FDT_ERR_TRUNCATED, standard meanings
1718 */
fdt_setprop_u64(void * fdt,int nodeoffset,const char * name,uint64_t val)1719 static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
1720 uint64_t val)
1721 {
1722 fdt64_t tmp = cpu_to_fdt64(val);
1723 return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1724 }
1725
1726 /**
1727 * fdt_setprop_cell - set a property to a single cell value
1728 * @fdt: pointer to the device tree blob
1729 * @nodeoffset: offset of the node whose property to change
1730 * @name: name of the property to change
1731 * @val: 32-bit integer value for the property (native endian)
1732 *
1733 * This is an alternative name for fdt_setprop_u32()
1734 *
1735 * Return: 0 on success, negative libfdt error value otherwise.
1736 */
fdt_setprop_cell(void * fdt,int nodeoffset,const char * name,uint32_t val)1737 static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
1738 uint32_t val)
1739 {
1740 return fdt_setprop_u32(fdt, nodeoffset, name, val);
1741 }
1742
1743 /**
1744 * fdt_setprop_string - set a property to a string value
1745 * @fdt: pointer to the device tree blob
1746 * @nodeoffset: offset of the node whose property to change
1747 * @name: name of the property to change
1748 * @str: string value for the property
1749 *
1750 * fdt_setprop_string() sets the value of the named property in the
1751 * given node to the given string value (using the length of the
1752 * string to determine the new length of the property), or creates a
1753 * new property with that value if it does not already exist.
1754 *
1755 * This function may insert or delete data from the blob, and will
1756 * therefore change the offsets of some existing nodes.
1757 *
1758 * returns:
1759 * 0, on success
1760 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1761 * contain the new property value
1762 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1763 * -FDT_ERR_BADLAYOUT,
1764 * -FDT_ERR_BADMAGIC,
1765 * -FDT_ERR_BADVERSION,
1766 * -FDT_ERR_BADSTATE,
1767 * -FDT_ERR_BADSTRUCTURE,
1768 * -FDT_ERR_BADLAYOUT,
1769 * -FDT_ERR_TRUNCATED, standard meanings
1770 */
1771 #define fdt_setprop_string(fdt, nodeoffset, name, str) \
1772 fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1773
1774
1775 /**
1776 * fdt_setprop_empty - set a property to an empty value
1777 * @fdt: pointer to the device tree blob
1778 * @nodeoffset: offset of the node whose property to change
1779 * @name: name of the property to change
1780 *
1781 * fdt_setprop_empty() sets the value of the named property in the
1782 * given node to an empty (zero length) value, or creates a new empty
1783 * property if it does not already exist.
1784 *
1785 * This function may insert or delete data from the blob, and will
1786 * therefore change the offsets of some existing nodes.
1787 *
1788 * returns:
1789 * 0, on success
1790 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1791 * contain the new property value
1792 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1793 * -FDT_ERR_BADLAYOUT,
1794 * -FDT_ERR_BADMAGIC,
1795 * -FDT_ERR_BADVERSION,
1796 * -FDT_ERR_BADSTATE,
1797 * -FDT_ERR_BADSTRUCTURE,
1798 * -FDT_ERR_BADLAYOUT,
1799 * -FDT_ERR_TRUNCATED, standard meanings
1800 */
1801 #define fdt_setprop_empty(fdt, nodeoffset, name) \
1802 fdt_setprop((fdt), (nodeoffset), (name), NULL, 0)
1803
1804 /**
1805 * fdt_appendprop - append to or create a property
1806 * @fdt: pointer to the device tree blob
1807 * @nodeoffset: offset of the node whose property to change
1808 * @name: name of the property to append to
1809 * @val: pointer to data to append to the property value
1810 * @len: length of the data to append to the property value
1811 *
1812 * fdt_appendprop() appends the value to the named property in the
1813 * given node, creating the property if it does not already exist.
1814 *
1815 * This function may insert data into the blob, and will therefore
1816 * change the offsets of some existing nodes.
1817 *
1818 * returns:
1819 * 0, on success
1820 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1821 * contain the new property value
1822 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1823 * -FDT_ERR_BADLAYOUT,
1824 * -FDT_ERR_BADMAGIC,
1825 * -FDT_ERR_BADVERSION,
1826 * -FDT_ERR_BADSTATE,
1827 * -FDT_ERR_BADSTRUCTURE,
1828 * -FDT_ERR_BADLAYOUT,
1829 * -FDT_ERR_TRUNCATED, standard meanings
1830 */
1831 int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
1832 const void *val, int len);
1833
1834 /**
1835 * fdt_appendprop_u32 - append a 32-bit integer value to a property
1836 * @fdt: pointer to the device tree blob
1837 * @nodeoffset: offset of the node whose property to change
1838 * @name: name of the property to change
1839 * @val: 32-bit integer value to append to the property (native endian)
1840 *
1841 * fdt_appendprop_u32() appends the given 32-bit integer value
1842 * (converting to big-endian if necessary) to the value of the named
1843 * property in the given node, or creates a new property with that
1844 * value if it does not already exist.
1845 *
1846 * This function may insert data into the blob, and will therefore
1847 * change the offsets of some existing nodes.
1848 *
1849 * returns:
1850 * 0, on success
1851 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1852 * contain the new property value
1853 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1854 * -FDT_ERR_BADLAYOUT,
1855 * -FDT_ERR_BADMAGIC,
1856 * -FDT_ERR_BADVERSION,
1857 * -FDT_ERR_BADSTATE,
1858 * -FDT_ERR_BADSTRUCTURE,
1859 * -FDT_ERR_BADLAYOUT,
1860 * -FDT_ERR_TRUNCATED, standard meanings
1861 */
fdt_appendprop_u32(void * fdt,int nodeoffset,const char * name,uint32_t val)1862 static inline int fdt_appendprop_u32(void *fdt, int nodeoffset,
1863 const char *name, uint32_t val)
1864 {
1865 fdt32_t tmp = cpu_to_fdt32(val);
1866 return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1867 }
1868
1869 /**
1870 * fdt_appendprop_u64 - append a 64-bit integer value to a property
1871 * @fdt: pointer to the device tree blob
1872 * @nodeoffset: offset of the node whose property to change
1873 * @name: name of the property to change
1874 * @val: 64-bit integer value to append to the property (native endian)
1875 *
1876 * fdt_appendprop_u64() appends the given 64-bit integer value
1877 * (converting to big-endian if necessary) to the value of the named
1878 * property in the given node, or creates a new property with that
1879 * value if it does not already exist.
1880 *
1881 * This function may insert data into the blob, and will therefore
1882 * change the offsets of some existing nodes.
1883 *
1884 * returns:
1885 * 0, on success
1886 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1887 * contain the new property value
1888 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1889 * -FDT_ERR_BADLAYOUT,
1890 * -FDT_ERR_BADMAGIC,
1891 * -FDT_ERR_BADVERSION,
1892 * -FDT_ERR_BADSTATE,
1893 * -FDT_ERR_BADSTRUCTURE,
1894 * -FDT_ERR_BADLAYOUT,
1895 * -FDT_ERR_TRUNCATED, standard meanings
1896 */
fdt_appendprop_u64(void * fdt,int nodeoffset,const char * name,uint64_t val)1897 static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
1898 const char *name, uint64_t val)
1899 {
1900 fdt64_t tmp = cpu_to_fdt64(val);
1901 return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1902 }
1903
1904 /**
1905 * fdt_appendprop_cell - append a single cell value to a property
1906 * @fdt: pointer to the device tree blob
1907 * @nodeoffset: offset of the node whose property to change
1908 * @name: name of the property to change
1909 * @val: 32-bit integer value to append to the property (native endian)
1910 *
1911 * This is an alternative name for fdt_appendprop_u32()
1912 *
1913 * Return: 0 on success, negative libfdt error value otherwise.
1914 */
fdt_appendprop_cell(void * fdt,int nodeoffset,const char * name,uint32_t val)1915 static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
1916 const char *name, uint32_t val)
1917 {
1918 return fdt_appendprop_u32(fdt, nodeoffset, name, val);
1919 }
1920
1921 /**
1922 * fdt_appendprop_string - append a string to a property
1923 * @fdt: pointer to the device tree blob
1924 * @nodeoffset: offset of the node whose property to change
1925 * @name: name of the property to change
1926 * @str: string value to append to the property
1927 *
1928 * fdt_appendprop_string() appends the given string to the value of
1929 * the named property in the given node, or creates a new property
1930 * with that value if it does not already exist.
1931 *
1932 * This function may insert data into the blob, and will therefore
1933 * change the offsets of some existing nodes.
1934 *
1935 * returns:
1936 * 0, on success
1937 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1938 * contain the new property value
1939 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1940 * -FDT_ERR_BADLAYOUT,
1941 * -FDT_ERR_BADMAGIC,
1942 * -FDT_ERR_BADVERSION,
1943 * -FDT_ERR_BADSTATE,
1944 * -FDT_ERR_BADSTRUCTURE,
1945 * -FDT_ERR_BADLAYOUT,
1946 * -FDT_ERR_TRUNCATED, standard meanings
1947 */
1948 #define fdt_appendprop_string(fdt, nodeoffset, name, str) \
1949 fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1950
1951 /**
1952 * fdt_appendprop_addrrange - append a address range property
1953 * @fdt: pointer to the device tree blob
1954 * @parent: offset of the parent node
1955 * @nodeoffset: offset of the node to add a property at
1956 * @name: name of property
1957 * @addr: start address of a given range
1958 * @size: size of a given range
1959 *
1960 * fdt_appendprop_addrrange() appends an address range value (start
1961 * address and size) to the value of the named property in the given
1962 * node, or creates a new property with that value if it does not
1963 * already exist.
1964 * If "name" is not specified, a default "reg" is used.
1965 * Cell sizes are determined by parent's #address-cells and #size-cells.
1966 *
1967 * This function may insert data into the blob, and will therefore
1968 * change the offsets of some existing nodes.
1969 *
1970 * returns:
1971 * 0, on success
1972 * -FDT_ERR_BADLAYOUT,
1973 * -FDT_ERR_BADMAGIC,
1974 * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1975 * #address-cells property
1976 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1977 * -FDT_ERR_BADSTATE,
1978 * -FDT_ERR_BADSTRUCTURE,
1979 * -FDT_ERR_BADVERSION,
1980 * -FDT_ERR_BADVALUE, addr or size doesn't fit to respective cells size
1981 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1982 * contain a new property
1983 * -FDT_ERR_TRUNCATED, standard meanings
1984 */
1985 int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
1986 const char *name, uint64_t addr, uint64_t size);
1987
1988 /**
1989 * fdt_delprop - delete a property
1990 * @fdt: pointer to the device tree blob
1991 * @nodeoffset: offset of the node whose property to nop
1992 * @name: name of the property to nop
1993 *
1994 * fdt_del_property() will delete the given property.
1995 *
1996 * This function will delete data from the blob, and will therefore
1997 * change the offsets of some existing nodes.
1998 *
1999 * returns:
2000 * 0, on success
2001 * -FDT_ERR_NOTFOUND, node does not have the named property
2002 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2003 * -FDT_ERR_BADLAYOUT,
2004 * -FDT_ERR_BADMAGIC,
2005 * -FDT_ERR_BADVERSION,
2006 * -FDT_ERR_BADSTATE,
2007 * -FDT_ERR_BADSTRUCTURE,
2008 * -FDT_ERR_TRUNCATED, standard meanings
2009 */
2010 int fdt_delprop(void *fdt, int nodeoffset, const char *name);
2011
2012 /**
2013 * fdt_add_subnode_namelen - creates a new node based on substring
2014 * @fdt: pointer to the device tree blob
2015 * @parentoffset: structure block offset of a node
2016 * @name: name of the subnode to create
2017 * @namelen: number of characters of name to consider
2018 *
2019 * Identical to fdt_add_subnode(), but use only the first @namelen
2020 * characters of @name as the name of the new node. This is useful for
2021 * creating subnodes based on a portion of a larger string, such as a
2022 * full path.
2023 *
2024 * Return: structure block offset of the created subnode (>=0),
2025 * negative libfdt error value otherwise
2026 */
2027 #ifndef SWIG /* Not available in Python */
2028 int fdt_add_subnode_namelen(void *fdt, int parentoffset,
2029 const char *name, int namelen);
2030 #endif
2031
2032 /**
2033 * fdt_add_subnode - creates a new node
2034 * @fdt: pointer to the device tree blob
2035 * @parentoffset: structure block offset of a node
2036 * @name: name of the subnode to locate
2037 *
2038 * fdt_add_subnode() creates a new node as a subnode of the node at
2039 * structure block offset parentoffset, with the given name (which
2040 * should include the unit address, if any).
2041 *
2042 * This function will insert data into the blob, and will therefore
2043 * change the offsets of some existing nodes.
2044 *
2045 * returns:
2046 * structure block offset of the created nodeequested subnode (>=0), on
2047 * success
2048 * -FDT_ERR_NOTFOUND, if the requested subnode does not exist
2049 * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
2050 * tag
2051 * -FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
2052 * the given name
2053 * -FDT_ERR_NOSPACE, if there is insufficient free space in the
2054 * blob to contain the new node
2055 * -FDT_ERR_NOSPACE
2056 * -FDT_ERR_BADLAYOUT
2057 * -FDT_ERR_BADMAGIC,
2058 * -FDT_ERR_BADVERSION,
2059 * -FDT_ERR_BADSTATE,
2060 * -FDT_ERR_BADSTRUCTURE,
2061 * -FDT_ERR_TRUNCATED, standard meanings.
2062 */
2063 int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
2064
2065 /**
2066 * fdt_del_node - delete a node (subtree)
2067 * @fdt: pointer to the device tree blob
2068 * @nodeoffset: offset of the node to nop
2069 *
2070 * fdt_del_node() will remove the given node, including all its
2071 * subnodes if any, from the blob.
2072 *
2073 * This function will delete data from the blob, and will therefore
2074 * change the offsets of some existing nodes.
2075 *
2076 * returns:
2077 * 0, on success
2078 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2079 * -FDT_ERR_BADLAYOUT,
2080 * -FDT_ERR_BADMAGIC,
2081 * -FDT_ERR_BADVERSION,
2082 * -FDT_ERR_BADSTATE,
2083 * -FDT_ERR_BADSTRUCTURE,
2084 * -FDT_ERR_TRUNCATED, standard meanings
2085 */
2086 int fdt_del_node(void *fdt, int nodeoffset);
2087
2088 /**
2089 * fdt_overlay_apply - Applies a DT overlay on a base DT
2090 * @fdt: pointer to the base device tree blob
2091 * @fdto: pointer to the device tree overlay blob
2092 *
2093 * fdt_overlay_apply() will apply the given device tree overlay on the
2094 * given base device tree.
2095 *
2096 * Expect the base device tree to be modified, even if the function
2097 * returns an error.
2098 *
2099 * returns:
2100 * 0, on success
2101 * -FDT_ERR_NOSPACE, there's not enough space in the base device tree
2102 * -FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
2103 * properties in the base DT
2104 * -FDT_ERR_BADPHANDLE,
2105 * -FDT_ERR_BADOVERLAY,
2106 * -FDT_ERR_NOPHANDLES,
2107 * -FDT_ERR_INTERNAL,
2108 * -FDT_ERR_BADLAYOUT,
2109 * -FDT_ERR_BADMAGIC,
2110 * -FDT_ERR_BADOFFSET,
2111 * -FDT_ERR_BADPATH,
2112 * -FDT_ERR_BADVERSION,
2113 * -FDT_ERR_BADSTRUCTURE,
2114 * -FDT_ERR_BADSTATE,
2115 * -FDT_ERR_TRUNCATED, standard meanings
2116 */
2117 int fdt_overlay_apply(void *fdt, void *fdto);
2118
2119 /**********************************************************************/
2120 /* Debugging / informational functions */
2121 /**********************************************************************/
2122
2123 const char *fdt_strerror(int errval);
2124
2125 #ifdef __cplusplus
2126 }
2127 #endif
2128
2129 #endif /* LIBFDT_H */
2130