1 /* $NetBSD: libfdt.h,v 1.1.1.3 2019/12/22 12:30:38 skrll Exp $ */
2
3 /* SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause) */
4 #ifndef LIBFDT_H
5 #define LIBFDT_H
6 /*
7 * libfdt - Flat Device Tree manipulation
8 * Copyright (C) 2006 David Gibson, IBM Corporation.
9 */
10
11 #include <libfdt_env.h>
12 #include <fdt.h>
13
14 #define FDT_FIRST_SUPPORTED_VERSION 0x02
15 #define FDT_LAST_SUPPORTED_VERSION 0x11
16
17 /* Error codes: informative error codes */
18 #define FDT_ERR_NOTFOUND 1
19 /* FDT_ERR_NOTFOUND: The requested node or property does not exist */
20 #define FDT_ERR_EXISTS 2
21 /* FDT_ERR_EXISTS: Attempted to create a node or property which
22 * already exists */
23 #define FDT_ERR_NOSPACE 3
24 /* FDT_ERR_NOSPACE: Operation needed to expand the device
25 * tree, but its buffer did not have sufficient space to
26 * contain the expanded tree. Use fdt_open_into() to move the
27 * device tree to a buffer with more space. */
28
29 /* Error codes: codes for bad parameters */
30 #define FDT_ERR_BADOFFSET 4
31 /* FDT_ERR_BADOFFSET: Function was passed a structure block
32 * offset which is out-of-bounds, or which points to an
33 * unsuitable part of the structure for the operation. */
34 #define FDT_ERR_BADPATH 5
35 /* FDT_ERR_BADPATH: Function was passed a badly formatted path
36 * (e.g. missing a leading / for a function which requires an
37 * absolute path) */
38 #define FDT_ERR_BADPHANDLE 6
39 /* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle.
40 * This can be caused either by an invalid phandle property
41 * length, or the phandle value was either 0 or -1, which are
42 * not permitted. */
43 #define FDT_ERR_BADSTATE 7
44 /* FDT_ERR_BADSTATE: Function was passed an incomplete device
45 * tree created by the sequential-write functions, which is
46 * not sufficiently complete for the requested operation. */
47
48 /* Error codes: codes for bad device tree blobs */
49 #define FDT_ERR_TRUNCATED 8
50 /* FDT_ERR_TRUNCATED: FDT or a sub-block is improperly
51 * terminated (overflows, goes outside allowed bounds, or
52 * isn't properly terminated). */
53 #define FDT_ERR_BADMAGIC 9
54 /* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
55 * device tree at all - it is missing the flattened device
56 * tree magic number. */
57 #define FDT_ERR_BADVERSION 10
58 /* FDT_ERR_BADVERSION: Given device tree has a version which
59 * can't be handled by the requested operation. For
60 * read-write functions, this may mean that fdt_open_into() is
61 * required to convert the tree to the expected version. */
62 #define FDT_ERR_BADSTRUCTURE 11
63 /* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt
64 * structure block or other serious error (e.g. misnested
65 * nodes, or subnodes preceding properties). */
66 #define FDT_ERR_BADLAYOUT 12
67 /* FDT_ERR_BADLAYOUT: For read-write functions, the given
68 * device tree has it's sub-blocks in an order that the
69 * function can't handle (memory reserve map, then structure,
70 * then strings). Use fdt_open_into() to reorganize the tree
71 * into a form suitable for the read-write operations. */
72
73 /* "Can't happen" error indicating a bug in libfdt */
74 #define FDT_ERR_INTERNAL 13
75 /* FDT_ERR_INTERNAL: libfdt has failed an internal assertion.
76 * Should never be returned, if it is, it indicates a bug in
77 * libfdt itself. */
78
79 /* Errors in device tree content */
80 #define FDT_ERR_BADNCELLS 14
81 /* FDT_ERR_BADNCELLS: Device tree has a #address-cells, #size-cells
82 * or similar property with a bad format or value */
83
84 #define FDT_ERR_BADVALUE 15
85 /* FDT_ERR_BADVALUE: Device tree has a property with an unexpected
86 * value. For example: a property expected to contain a string list
87 * is not NUL-terminated within the length of its value. */
88
89 #define FDT_ERR_BADOVERLAY 16
90 /* FDT_ERR_BADOVERLAY: The device tree overlay, while
91 * correctly structured, cannot be applied due to some
92 * unexpected or missing value, property or node. */
93
94 #define FDT_ERR_NOPHANDLES 17
95 /* FDT_ERR_NOPHANDLES: The device tree doesn't have any
96 * phandle available anymore without causing an overflow */
97
98 #define FDT_ERR_BADFLAGS 18
99 /* FDT_ERR_BADFLAGS: The function was passed a flags field that
100 * contains invalid flags or an invalid combination of flags. */
101
102 #define FDT_ERR_MAX 18
103
104 /* constants */
105 #define FDT_MAX_PHANDLE 0xfffffffe
106 /* Valid values for phandles range from 1 to 2^32-2. */
107
108 /**********************************************************************/
109 /* Low-level functions (you probably don't need these) */
110 /**********************************************************************/
111
112 #ifndef SWIG /* This function is not useful in Python */
113 const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen);
114 #endif
fdt_offset_ptr_w(void * fdt,int offset,int checklen)115 static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
116 {
117 return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
118 }
119
120 uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
121
122 /*
123 * Alignment helpers:
124 * These helpers access words from a device tree blob. They're
125 * built to work even with unaligned pointers on platforms (ike
126 * ARM) that don't like unaligned loads and stores
127 */
128
fdt32_ld(const fdt32_t * p)129 static inline uint32_t fdt32_ld(const fdt32_t *p)
130 {
131 const uint8_t *bp = (const uint8_t *)p;
132
133 return ((uint32_t)bp[0] << 24)
134 | ((uint32_t)bp[1] << 16)
135 | ((uint32_t)bp[2] << 8)
136 | bp[3];
137 }
138
fdt32_st(void * property,uint32_t value)139 static inline void fdt32_st(void *property, uint32_t value)
140 {
141 uint8_t *bp = property;
142
143 bp[0] = value >> 24;
144 bp[1] = (value >> 16) & 0xff;
145 bp[2] = (value >> 8) & 0xff;
146 bp[3] = value & 0xff;
147 }
148
fdt64_ld(const fdt64_t * p)149 static inline uint64_t fdt64_ld(const fdt64_t *p)
150 {
151 const uint8_t *bp = (const uint8_t *)p;
152
153 return ((uint64_t)bp[0] << 56)
154 | ((uint64_t)bp[1] << 48)
155 | ((uint64_t)bp[2] << 40)
156 | ((uint64_t)bp[3] << 32)
157 | ((uint64_t)bp[4] << 24)
158 | ((uint64_t)bp[5] << 16)
159 | ((uint64_t)bp[6] << 8)
160 | bp[7];
161 }
162
fdt64_st(void * property,uint64_t value)163 static inline void fdt64_st(void *property, uint64_t value)
164 {
165 uint8_t *bp = property;
166
167 bp[0] = value >> 56;
168 bp[1] = (value >> 48) & 0xff;
169 bp[2] = (value >> 40) & 0xff;
170 bp[3] = (value >> 32) & 0xff;
171 bp[4] = (value >> 24) & 0xff;
172 bp[5] = (value >> 16) & 0xff;
173 bp[6] = (value >> 8) & 0xff;
174 bp[7] = value & 0xff;
175 }
176
177 /**********************************************************************/
178 /* Traversal functions */
179 /**********************************************************************/
180
181 int fdt_next_node(const void *fdt, int offset, int *depth);
182
183 /**
184 * fdt_first_subnode() - get offset of first direct subnode
185 *
186 * @fdt: FDT blob
187 * @offset: Offset of node to check
188 * @return offset of first subnode, or -FDT_ERR_NOTFOUND if there is none
189 */
190 int fdt_first_subnode(const void *fdt, int offset);
191
192 /**
193 * fdt_next_subnode() - get offset of next direct subnode
194 *
195 * After first calling fdt_first_subnode(), call this function repeatedly to
196 * get direct subnodes of a parent node.
197 *
198 * @fdt: FDT blob
199 * @offset: Offset of previous subnode
200 * @return offset of next subnode, or -FDT_ERR_NOTFOUND if there are no more
201 * subnodes
202 */
203 int fdt_next_subnode(const void *fdt, int offset);
204
205 /**
206 * fdt_for_each_subnode - iterate over all subnodes of a parent
207 *
208 * @node: child node (int, lvalue)
209 * @fdt: FDT blob (const void *)
210 * @parent: parent node (int)
211 *
212 * This is actually a wrapper around a for loop and would be used like so:
213 *
214 * fdt_for_each_subnode(node, fdt, parent) {
215 * Use node
216 * ...
217 * }
218 *
219 * if ((node < 0) && (node != -FDT_ERR_NOTFOUND)) {
220 * Error handling
221 * }
222 *
223 * Note that this is implemented as a macro and @node is used as
224 * iterator in the loop. The parent variable be constant or even a
225 * literal.
226 *
227 */
228 #define fdt_for_each_subnode(node, fdt, parent) \
229 for (node = fdt_first_subnode(fdt, parent); \
230 node >= 0; \
231 node = fdt_next_subnode(fdt, node))
232
233 /**********************************************************************/
234 /* General functions */
235 /**********************************************************************/
236 #define fdt_get_header(fdt, field) \
237 (fdt32_ld(&((const struct fdt_header *)(fdt))->field))
238 #define fdt_magic(fdt) (fdt_get_header(fdt, magic))
239 #define fdt_totalsize(fdt) (fdt_get_header(fdt, totalsize))
240 #define fdt_off_dt_struct(fdt) (fdt_get_header(fdt, off_dt_struct))
241 #define fdt_off_dt_strings(fdt) (fdt_get_header(fdt, off_dt_strings))
242 #define fdt_off_mem_rsvmap(fdt) (fdt_get_header(fdt, off_mem_rsvmap))
243 #define fdt_version(fdt) (fdt_get_header(fdt, version))
244 #define fdt_last_comp_version(fdt) (fdt_get_header(fdt, last_comp_version))
245 #define fdt_boot_cpuid_phys(fdt) (fdt_get_header(fdt, boot_cpuid_phys))
246 #define fdt_size_dt_strings(fdt) (fdt_get_header(fdt, size_dt_strings))
247 #define fdt_size_dt_struct(fdt) (fdt_get_header(fdt, size_dt_struct))
248
249 #define fdt_set_hdr_(name) \
250 static inline void fdt_set_##name(void *fdt, uint32_t val) \
251 { \
252 struct fdt_header *fdth = (struct fdt_header *)fdt; \
253 fdth->name = cpu_to_fdt32(val); \
254 }
255 fdt_set_hdr_(magic);
256 fdt_set_hdr_(totalsize);
257 fdt_set_hdr_(off_dt_struct);
258 fdt_set_hdr_(off_dt_strings);
259 fdt_set_hdr_(off_mem_rsvmap);
260 fdt_set_hdr_(version);
261 fdt_set_hdr_(last_comp_version);
262 fdt_set_hdr_(boot_cpuid_phys);
263 fdt_set_hdr_(size_dt_strings);
264 fdt_set_hdr_(size_dt_struct);
265 #undef fdt_set_hdr_
266
267 /**
268 * fdt_header_size - return the size of the tree's header
269 * @fdt: pointer to a flattened device tree
270 */
271 size_t fdt_header_size_(uint32_t version);
fdt_header_size(const void * fdt)272 static inline size_t fdt_header_size(const void *fdt)
273 {
274 return fdt_header_size_(fdt_version(fdt));
275 }
276
277 /**
278 * fdt_check_header - sanity check a device tree header
279
280 * @fdt: pointer to data which might be a flattened device tree
281 *
282 * fdt_check_header() checks that the given buffer contains what
283 * appears to be a flattened device tree, and that the header contains
284 * valid information (to the extent that can be determined from the
285 * header alone).
286 *
287 * returns:
288 * 0, if the buffer appears to contain a valid device tree
289 * -FDT_ERR_BADMAGIC,
290 * -FDT_ERR_BADVERSION,
291 * -FDT_ERR_BADSTATE,
292 * -FDT_ERR_TRUNCATED, standard meanings, as above
293 */
294 int fdt_check_header(const void *fdt);
295
296 /**
297 * fdt_move - move a device tree around in memory
298 * @fdt: pointer to the device tree to move
299 * @buf: pointer to memory where the device is to be moved
300 * @bufsize: size of the memory space at buf
301 *
302 * fdt_move() relocates, if possible, the device tree blob located at
303 * fdt to the buffer at buf of size bufsize. The buffer may overlap
304 * with the existing device tree blob at fdt. Therefore,
305 * fdt_move(fdt, fdt, fdt_totalsize(fdt))
306 * should always succeed.
307 *
308 * returns:
309 * 0, on success
310 * -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
311 * -FDT_ERR_BADMAGIC,
312 * -FDT_ERR_BADVERSION,
313 * -FDT_ERR_BADSTATE, standard meanings
314 */
315 int fdt_move(const void *fdt, void *buf, int bufsize);
316
317 /**********************************************************************/
318 /* Read-only functions */
319 /**********************************************************************/
320
321 int fdt_check_full(const void *fdt, size_t bufsize);
322
323 /**
324 * fdt_get_string - retrieve a string from the strings block of a device tree
325 * @fdt: pointer to the device tree blob
326 * @stroffset: offset of the string within the strings block (native endian)
327 * @lenp: optional pointer to return the string's length
328 *
329 * fdt_get_string() retrieves a pointer to a single string from the
330 * strings block of the device tree blob at fdt, and optionally also
331 * returns the string's length in *lenp.
332 *
333 * returns:
334 * a pointer to the string, on success
335 * NULL, if stroffset is out of bounds, or doesn't point to a valid string
336 */
337 const char *fdt_get_string(const void *fdt, int stroffset, int *lenp);
338
339 /**
340 * fdt_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 *
344 * fdt_string() retrieves a pointer to a single string from the
345 * strings block of the device tree blob at fdt.
346 *
347 * returns:
348 * a pointer to the string, on success
349 * NULL, if stroffset is out of bounds, or doesn't point to a valid string
350 */
351 const char *fdt_string(const void *fdt, int stroffset);
352
353 /**
354 * fdt_find_max_phandle - find and return the highest phandle in a tree
355 * @fdt: pointer to the device tree blob
356 * @phandle: return location for the highest phandle value found in the tree
357 *
358 * fdt_find_max_phandle() finds the highest phandle value in the given device
359 * tree. The value returned in @phandle is only valid if the function returns
360 * success.
361 *
362 * returns:
363 * 0 on success or a negative error code on failure
364 */
365 int fdt_find_max_phandle(const void *fdt, uint32_t *phandle);
366
367 /**
368 * fdt_get_max_phandle - retrieves the highest phandle in a tree
369 * @fdt: pointer to the device tree blob
370 *
371 * fdt_get_max_phandle retrieves the highest phandle in the given
372 * device tree. This will ignore badly formatted phandles, or phandles
373 * with a value of 0 or -1.
374 *
375 * This function is deprecated in favour of fdt_find_max_phandle().
376 *
377 * returns:
378 * the highest phandle on success
379 * 0, if no phandle was found in the device tree
380 * -1, if an error occurred
381 */
fdt_get_max_phandle(const void * fdt)382 static inline uint32_t fdt_get_max_phandle(const void *fdt)
383 {
384 uint32_t phandle;
385 int err;
386
387 err = fdt_find_max_phandle(fdt, &phandle);
388 if (err < 0)
389 return (uint32_t)-1;
390
391 return phandle;
392 }
393
394 /**
395 * fdt_generate_phandle - return a new, unused phandle for a device tree blob
396 * @fdt: pointer to the device tree blob
397 * @phandle: return location for the new phandle
398 *
399 * Walks the device tree blob and looks for the highest phandle value. On
400 * success, the new, unused phandle value (one higher than the previously
401 * highest phandle value in the device tree blob) will be returned in the
402 * @phandle parameter.
403 *
404 * Returns:
405 * 0 on success or a negative error-code on failure
406 */
407 int fdt_generate_phandle(const void *fdt, uint32_t *phandle);
408
409 /**
410 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
411 * @fdt: pointer to the device tree blob
412 *
413 * Returns the number of entries in the device tree blob's memory
414 * reservation map. This does not include the terminating 0,0 entry
415 * or any other (0,0) entries reserved for expansion.
416 *
417 * returns:
418 * the number of entries
419 */
420 int fdt_num_mem_rsv(const void *fdt);
421
422 /**
423 * fdt_get_mem_rsv - retrieve one memory reserve map entry
424 * @fdt: pointer to the device tree blob
425 * @address, @size: pointers to 64-bit variables
426 *
427 * On success, *address and *size will contain the address and size of
428 * the n-th reserve map entry from the device tree blob, in
429 * native-endian format.
430 *
431 * returns:
432 * 0, on success
433 * -FDT_ERR_BADMAGIC,
434 * -FDT_ERR_BADVERSION,
435 * -FDT_ERR_BADSTATE, standard meanings
436 */
437 int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);
438
439 /**
440 * fdt_subnode_offset_namelen - find a subnode based on substring
441 * @fdt: pointer to the device tree blob
442 * @parentoffset: structure block offset of a node
443 * @name: name of the subnode to locate
444 * @namelen: number of characters of name to consider
445 *
446 * Identical to fdt_subnode_offset(), but only examine the first
447 * namelen characters of name for matching the subnode name. This is
448 * useful for finding subnodes based on a portion of a larger string,
449 * such as a full path.
450 */
451 #ifndef SWIG /* Not available in Python */
452 int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
453 const char *name, int namelen);
454 #endif
455 /**
456 * fdt_subnode_offset - find a subnode of a given node
457 * @fdt: pointer to the device tree blob
458 * @parentoffset: structure block offset of a node
459 * @name: name of the subnode to locate
460 *
461 * fdt_subnode_offset() finds a subnode of the node at structure block
462 * offset parentoffset with the given name. name may include a unit
463 * address, in which case fdt_subnode_offset() will find the subnode
464 * with that unit address, or the unit address may be omitted, in
465 * which case fdt_subnode_offset() will find an arbitrary subnode
466 * whose name excluding unit address matches the given name.
467 *
468 * returns:
469 * structure block offset of the requested subnode (>=0), on success
470 * -FDT_ERR_NOTFOUND, if the requested subnode does not exist
471 * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
472 * tag
473 * -FDT_ERR_BADMAGIC,
474 * -FDT_ERR_BADVERSION,
475 * -FDT_ERR_BADSTATE,
476 * -FDT_ERR_BADSTRUCTURE,
477 * -FDT_ERR_TRUNCATED, standard meanings.
478 */
479 int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
480
481 /**
482 * fdt_path_offset_namelen - find a tree node by its full path
483 * @fdt: pointer to the device tree blob
484 * @path: full path of the node to locate
485 * @namelen: number of characters of path to consider
486 *
487 * Identical to fdt_path_offset(), but only consider the first namelen
488 * characters of path as the path name.
489 */
490 #ifndef SWIG /* Not available in Python */
491 int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen);
492 #endif
493
494 /**
495 * fdt_path_offset - find a tree node by its full path
496 * @fdt: pointer to the device tree blob
497 * @path: full path of the node to locate
498 *
499 * fdt_path_offset() finds a node of a given path in the device tree.
500 * Each path component may omit the unit address portion, but the
501 * results of this are undefined if any such path component is
502 * ambiguous (that is if there are multiple nodes at the relevant
503 * level matching the given component, differentiated only by unit
504 * address).
505 *
506 * returns:
507 * structure block offset of the node with the requested path (>=0), on
508 * success
509 * -FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
510 * -FDT_ERR_NOTFOUND, if the requested node does not exist
511 * -FDT_ERR_BADMAGIC,
512 * -FDT_ERR_BADVERSION,
513 * -FDT_ERR_BADSTATE,
514 * -FDT_ERR_BADSTRUCTURE,
515 * -FDT_ERR_TRUNCATED, standard meanings.
516 */
517 int fdt_path_offset(const void *fdt, const char *path);
518
519 /**
520 * fdt_get_name - retrieve the name of a given node
521 * @fdt: pointer to the device tree blob
522 * @nodeoffset: structure block offset of the starting node
523 * @lenp: pointer to an integer variable (will be overwritten) or NULL
524 *
525 * fdt_get_name() retrieves the name (including unit address) of the
526 * device tree node at structure block offset nodeoffset. If lenp is
527 * non-NULL, the length of this name is also returned, in the integer
528 * pointed to by lenp.
529 *
530 * returns:
531 * pointer to the node's name, on success
532 * If lenp is non-NULL, *lenp contains the length of that name
533 * (>=0)
534 * NULL, on error
535 * if lenp is non-NULL *lenp contains an error code (<0):
536 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
537 * tag
538 * -FDT_ERR_BADMAGIC,
539 * -FDT_ERR_BADVERSION,
540 * -FDT_ERR_BADSTATE, standard meanings
541 */
542 const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
543
544 /**
545 * fdt_first_property_offset - find the offset of a node's first property
546 * @fdt: pointer to the device tree blob
547 * @nodeoffset: structure block offset of a node
548 *
549 * fdt_first_property_offset() finds the first property of the node at
550 * the given structure block offset.
551 *
552 * returns:
553 * structure block offset of the property (>=0), on success
554 * -FDT_ERR_NOTFOUND, if the requested node has no properties
555 * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
556 * -FDT_ERR_BADMAGIC,
557 * -FDT_ERR_BADVERSION,
558 * -FDT_ERR_BADSTATE,
559 * -FDT_ERR_BADSTRUCTURE,
560 * -FDT_ERR_TRUNCATED, standard meanings.
561 */
562 int fdt_first_property_offset(const void *fdt, int nodeoffset);
563
564 /**
565 * fdt_next_property_offset - step through a node's properties
566 * @fdt: pointer to the device tree blob
567 * @offset: structure block offset of a property
568 *
569 * fdt_next_property_offset() finds the property immediately after the
570 * one at the given structure block offset. This will be a property
571 * of the same node as the given property.
572 *
573 * returns:
574 * structure block offset of the next property (>=0), on success
575 * -FDT_ERR_NOTFOUND, if the given property is the last in its node
576 * -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP 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_next_property_offset(const void *fdt, int offset);
584
585 /**
586 * fdt_for_each_property_offset - iterate over all properties of a node
587 *
588 * @property_offset: property offset (int, lvalue)
589 * @fdt: FDT blob (const void *)
590 * @node: node offset (int)
591 *
592 * This is actually a wrapper around a for loop and would be used like so:
593 *
594 * fdt_for_each_property_offset(property, fdt, node) {
595 * Use property
596 * ...
597 * }
598 *
599 * if ((property < 0) && (property != -FDT_ERR_NOTFOUND)) {
600 * Error handling
601 * }
602 *
603 * Note that this is implemented as a macro and property is used as
604 * iterator in the loop. The node variable can be constant or even a
605 * literal.
606 */
607 #define fdt_for_each_property_offset(property, fdt, node) \
608 for (property = fdt_first_property_offset(fdt, node); \
609 property >= 0; \
610 property = fdt_next_property_offset(fdt, property))
611
612 /**
613 * fdt_get_property_by_offset - retrieve the property at a given offset
614 * @fdt: pointer to the device tree blob
615 * @offset: offset of the property to retrieve
616 * @lenp: pointer to an integer variable (will be overwritten) or NULL
617 *
618 * fdt_get_property_by_offset() retrieves a pointer to the
619 * fdt_property structure within the device tree blob at the given
620 * offset. If lenp is non-NULL, the length of the property value is
621 * also returned, in the integer pointed to by lenp.
622 *
623 * Note that this code only works on device tree versions >= 16. fdt_getprop()
624 * works on all versions.
625 *
626 * returns:
627 * pointer to the structure representing the property
628 * if lenp is non-NULL, *lenp contains the length of the property
629 * value (>=0)
630 * NULL, on error
631 * if lenp is non-NULL, *lenp contains an error code (<0):
632 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
633 * -FDT_ERR_BADMAGIC,
634 * -FDT_ERR_BADVERSION,
635 * -FDT_ERR_BADSTATE,
636 * -FDT_ERR_BADSTRUCTURE,
637 * -FDT_ERR_TRUNCATED, standard meanings
638 */
639 const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
640 int offset,
641 int *lenp);
642
643 /**
644 * fdt_get_property_namelen - find a property based on substring
645 * @fdt: pointer to the device tree blob
646 * @nodeoffset: offset of the node whose property to find
647 * @name: name of the property to find
648 * @namelen: number of characters of name to consider
649 * @lenp: pointer to an integer variable (will be overwritten) or NULL
650 *
651 * Identical to fdt_get_property(), but only examine the first namelen
652 * characters of name for matching the property name.
653 */
654 #ifndef SWIG /* Not available in Python */
655 const struct fdt_property *fdt_get_property_namelen(const void *fdt,
656 int nodeoffset,
657 const char *name,
658 int namelen, int *lenp);
659 #endif
660
661 /**
662 * fdt_get_property - find a given property in a given node
663 * @fdt: pointer to the device tree blob
664 * @nodeoffset: offset of the node whose property to find
665 * @name: name of the property to find
666 * @lenp: pointer to an integer variable (will be overwritten) or NULL
667 *
668 * fdt_get_property() retrieves a pointer to the fdt_property
669 * structure within the device tree blob corresponding to the property
670 * named 'name' of the node at offset nodeoffset. If lenp is
671 * non-NULL, the length of the property value is also returned, in the
672 * integer pointed to by lenp.
673 *
674 * returns:
675 * pointer to the structure representing the property
676 * if lenp is non-NULL, *lenp contains the length of the property
677 * value (>=0)
678 * NULL, on error
679 * if lenp is non-NULL, *lenp contains an error code (<0):
680 * -FDT_ERR_NOTFOUND, node does not have named property
681 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
682 * tag
683 * -FDT_ERR_BADMAGIC,
684 * -FDT_ERR_BADVERSION,
685 * -FDT_ERR_BADSTATE,
686 * -FDT_ERR_BADSTRUCTURE,
687 * -FDT_ERR_TRUNCATED, standard meanings
688 */
689 const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
690 const char *name, int *lenp);
fdt_get_property_w(void * fdt,int nodeoffset,const char * name,int * lenp)691 static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
692 const char *name,
693 int *lenp)
694 {
695 return (struct fdt_property *)(uintptr_t)
696 fdt_get_property(fdt, nodeoffset, name, lenp);
697 }
698
699 /**
700 * fdt_getprop_by_offset - retrieve the value of a property at a given offset
701 * @fdt: pointer to the device tree blob
702 * @offset: offset of the property to read
703 * @namep: pointer to a string variable (will be overwritten) or NULL
704 * @lenp: pointer to an integer variable (will be overwritten) or NULL
705 *
706 * fdt_getprop_by_offset() retrieves a pointer to the value of the
707 * property at structure block offset 'offset' (this will be a pointer
708 * to within the device blob itself, not a copy of the value). If
709 * lenp is non-NULL, the length of the property value is also
710 * returned, in the integer pointed to by lenp. If namep is non-NULL,
711 * the property's namne will also be returned in the char * pointed to
712 * by namep (this will be a pointer to within the device tree's string
713 * block, not a new copy of the name).
714 *
715 * returns:
716 * pointer to the property's value
717 * if lenp is non-NULL, *lenp contains the length of the property
718 * value (>=0)
719 * if namep is non-NULL *namep contiains a pointer to the property
720 * name.
721 * NULL, on error
722 * if lenp is non-NULL, *lenp contains an error code (<0):
723 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
724 * -FDT_ERR_BADMAGIC,
725 * -FDT_ERR_BADVERSION,
726 * -FDT_ERR_BADSTATE,
727 * -FDT_ERR_BADSTRUCTURE,
728 * -FDT_ERR_TRUNCATED, standard meanings
729 */
730 #ifndef SWIG /* This function is not useful in Python */
731 const void *fdt_getprop_by_offset(const void *fdt, int offset,
732 const char **namep, int *lenp);
733 #endif
734
735 /**
736 * fdt_getprop_namelen - get property value based on substring
737 * @fdt: pointer to the device tree blob
738 * @nodeoffset: offset of the node whose property to find
739 * @name: name of the property to find
740 * @namelen: number of characters of name to consider
741 * @lenp: pointer to an integer variable (will be overwritten) or NULL
742 *
743 * Identical to fdt_getprop(), but only examine the first namelen
744 * characters of name for matching the property name.
745 */
746 #ifndef SWIG /* Not available in Python */
747 const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
748 const char *name, int namelen, int *lenp);
fdt_getprop_namelen_w(void * fdt,int nodeoffset,const char * name,int namelen,int * lenp)749 static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset,
750 const char *name, int namelen,
751 int *lenp)
752 {
753 return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name,
754 namelen, lenp);
755 }
756 #endif
757
758 /**
759 * fdt_getprop - retrieve the value of a given property
760 * @fdt: pointer to the device tree blob
761 * @nodeoffset: offset of the node whose property to find
762 * @name: name of the property to find
763 * @lenp: pointer to an integer variable (will be overwritten) or NULL
764 *
765 * fdt_getprop() retrieves a pointer to the value of the property
766 * named 'name' of the node at offset nodeoffset (this will be a
767 * pointer to within the device blob itself, not a copy of the value).
768 * If lenp is non-NULL, the length of the property value is also
769 * returned, in the integer pointed to by lenp.
770 *
771 * returns:
772 * pointer to the property's value
773 * if lenp is non-NULL, *lenp contains the length of the property
774 * value (>=0)
775 * NULL, on error
776 * if lenp is non-NULL, *lenp contains an error code (<0):
777 * -FDT_ERR_NOTFOUND, node does not have named property
778 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
779 * tag
780 * -FDT_ERR_BADMAGIC,
781 * -FDT_ERR_BADVERSION,
782 * -FDT_ERR_BADSTATE,
783 * -FDT_ERR_BADSTRUCTURE,
784 * -FDT_ERR_TRUNCATED, standard meanings
785 */
786 const void *fdt_getprop(const void *fdt, int nodeoffset,
787 const char *name, int *lenp);
fdt_getprop_w(void * fdt,int nodeoffset,const char * name,int * lenp)788 static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
789 const char *name, int *lenp)
790 {
791 return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
792 }
793
794 /**
795 * fdt_get_phandle - retrieve the phandle of a given node
796 * @fdt: pointer to the device tree blob
797 * @nodeoffset: structure block offset of the node
798 *
799 * fdt_get_phandle() retrieves the phandle of the device tree node at
800 * structure block offset nodeoffset.
801 *
802 * returns:
803 * the phandle of the node at nodeoffset, on success (!= 0, != -1)
804 * 0, if the node has no phandle, or another error occurs
805 */
806 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
807
808 /**
809 * fdt_get_alias_namelen - get alias based on substring
810 * @fdt: pointer to the device tree blob
811 * @name: name of the alias th look up
812 * @namelen: number of characters of name to consider
813 *
814 * Identical to fdt_get_alias(), but only examine the first namelen
815 * characters of name for matching the alias name.
816 */
817 #ifndef SWIG /* Not available in Python */
818 const char *fdt_get_alias_namelen(const void *fdt,
819 const char *name, int namelen);
820 #endif
821
822 /**
823 * fdt_get_alias - retrieve the path referenced by a given alias
824 * @fdt: pointer to the device tree blob
825 * @name: name of the alias th look up
826 *
827 * fdt_get_alias() retrieves the value of a given alias. That is, the
828 * value of the property named 'name' in the node /aliases.
829 *
830 * returns:
831 * a pointer to the expansion of the alias named 'name', if it exists
832 * NULL, if the given alias or the /aliases node does not exist
833 */
834 const char *fdt_get_alias(const void *fdt, const char *name);
835
836 /**
837 * fdt_get_path - determine the full path of a node
838 * @fdt: pointer to the device tree blob
839 * @nodeoffset: offset of the node whose path to find
840 * @buf: character buffer to contain the returned path (will be overwritten)
841 * @buflen: size of the character buffer at buf
842 *
843 * fdt_get_path() computes the full path of the node at offset
844 * nodeoffset, and records that path in the buffer at buf.
845 *
846 * NOTE: This function is expensive, as it must scan the device tree
847 * structure from the start to nodeoffset.
848 *
849 * returns:
850 * 0, on success
851 * buf contains the absolute path of the node at
852 * nodeoffset, as a NUL-terminated string.
853 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
854 * -FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
855 * characters and will not fit in the given buffer.
856 * -FDT_ERR_BADMAGIC,
857 * -FDT_ERR_BADVERSION,
858 * -FDT_ERR_BADSTATE,
859 * -FDT_ERR_BADSTRUCTURE, standard meanings
860 */
861 int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
862
863 /**
864 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
865 * @fdt: pointer to the device tree blob
866 * @nodeoffset: offset of the node whose parent to find
867 * @supernodedepth: depth of the ancestor to find
868 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
869 *
870 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
871 * at a specific depth from the root (where the root itself has depth
872 * 0, its immediate subnodes depth 1 and so forth). So
873 * fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
874 * will always return 0, the offset of the root node. If the node at
875 * nodeoffset has depth D, then:
876 * fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
877 * will return nodeoffset itself.
878 *
879 * NOTE: This function is expensive, as it must scan the device tree
880 * structure from the start to nodeoffset.
881 *
882 * returns:
883 * structure block offset of the node at node offset's ancestor
884 * of depth supernodedepth (>=0), on success
885 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
886 * -FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of
887 * nodeoffset
888 * -FDT_ERR_BADMAGIC,
889 * -FDT_ERR_BADVERSION,
890 * -FDT_ERR_BADSTATE,
891 * -FDT_ERR_BADSTRUCTURE, standard meanings
892 */
893 int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
894 int supernodedepth, int *nodedepth);
895
896 /**
897 * fdt_node_depth - find the depth of a given node
898 * @fdt: pointer to the device tree blob
899 * @nodeoffset: offset of the node whose parent to find
900 *
901 * fdt_node_depth() finds the depth of a given node. The root node
902 * has depth 0, its immediate subnodes depth 1 and so forth.
903 *
904 * NOTE: This function is expensive, as it must scan the device tree
905 * structure from the start to nodeoffset.
906 *
907 * returns:
908 * depth of the node at nodeoffset (>=0), on success
909 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
910 * -FDT_ERR_BADMAGIC,
911 * -FDT_ERR_BADVERSION,
912 * -FDT_ERR_BADSTATE,
913 * -FDT_ERR_BADSTRUCTURE, standard meanings
914 */
915 int fdt_node_depth(const void *fdt, int nodeoffset);
916
917 /**
918 * fdt_parent_offset - find the parent of a given node
919 * @fdt: pointer to the device tree blob
920 * @nodeoffset: offset of the node whose parent to find
921 *
922 * fdt_parent_offset() locates the parent node of a given node (that
923 * is, it finds the offset of the node which contains the node at
924 * nodeoffset as a subnode).
925 *
926 * NOTE: This function is expensive, as it must scan the device tree
927 * structure from the start to nodeoffset, *twice*.
928 *
929 * returns:
930 * structure block offset of the parent of the node at nodeoffset
931 * (>=0), on success
932 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
933 * -FDT_ERR_BADMAGIC,
934 * -FDT_ERR_BADVERSION,
935 * -FDT_ERR_BADSTATE,
936 * -FDT_ERR_BADSTRUCTURE, standard meanings
937 */
938 int fdt_parent_offset(const void *fdt, int nodeoffset);
939
940 /**
941 * fdt_node_offset_by_prop_value - find nodes with a given property value
942 * @fdt: pointer to the device tree blob
943 * @startoffset: only find nodes after this offset
944 * @propname: property name to check
945 * @propval: property value to search for
946 * @proplen: length of the value in propval
947 *
948 * fdt_node_offset_by_prop_value() returns the offset of the first
949 * node after startoffset, which has a property named propname whose
950 * value is of length proplen and has value equal to propval; or if
951 * startoffset is -1, the very first such node in the tree.
952 *
953 * To iterate through all nodes matching the criterion, the following
954 * idiom can be used:
955 * offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
956 * propval, proplen);
957 * while (offset != -FDT_ERR_NOTFOUND) {
958 * // other code here
959 * offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
960 * propval, proplen);
961 * }
962 *
963 * Note the -1 in the first call to the function, if 0 is used here
964 * instead, the function will never locate the root node, even if it
965 * matches the criterion.
966 *
967 * returns:
968 * structure block offset of the located node (>= 0, >startoffset),
969 * on success
970 * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
971 * tree after startoffset
972 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
973 * -FDT_ERR_BADMAGIC,
974 * -FDT_ERR_BADVERSION,
975 * -FDT_ERR_BADSTATE,
976 * -FDT_ERR_BADSTRUCTURE, standard meanings
977 */
978 int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
979 const char *propname,
980 const void *propval, int proplen);
981
982 /**
983 * fdt_node_offset_by_phandle - find the node with a given phandle
984 * @fdt: pointer to the device tree blob
985 * @phandle: phandle value
986 *
987 * fdt_node_offset_by_phandle() returns the offset of the node
988 * which has the given phandle value. If there is more than one node
989 * in the tree with the given phandle (an invalid tree), results are
990 * undefined.
991 *
992 * returns:
993 * structure block offset of the located node (>= 0), on success
994 * -FDT_ERR_NOTFOUND, no node with that phandle exists
995 * -FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
996 * -FDT_ERR_BADMAGIC,
997 * -FDT_ERR_BADVERSION,
998 * -FDT_ERR_BADSTATE,
999 * -FDT_ERR_BADSTRUCTURE, standard meanings
1000 */
1001 int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
1002
1003 /**
1004 * fdt_node_check_compatible: check a node's compatible property
1005 * @fdt: pointer to the device tree blob
1006 * @nodeoffset: offset of a tree node
1007 * @compatible: string to match against
1008 *
1009 *
1010 * fdt_node_check_compatible() returns 0 if the given node contains a
1011 * 'compatible' property with the given string as one of its elements,
1012 * it returns non-zero otherwise, or on error.
1013 *
1014 * returns:
1015 * 0, if the node has a 'compatible' property listing the given string
1016 * 1, if the node has a 'compatible' property, but it does not list
1017 * the given string
1018 * -FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
1019 * -FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
1020 * -FDT_ERR_BADMAGIC,
1021 * -FDT_ERR_BADVERSION,
1022 * -FDT_ERR_BADSTATE,
1023 * -FDT_ERR_BADSTRUCTURE, standard meanings
1024 */
1025 int fdt_node_check_compatible(const void *fdt, int nodeoffset,
1026 const char *compatible);
1027
1028 /**
1029 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
1030 * @fdt: pointer to the device tree blob
1031 * @startoffset: only find nodes after this offset
1032 * @compatible: 'compatible' string to match against
1033 *
1034 * fdt_node_offset_by_compatible() returns the offset of the first
1035 * node after startoffset, which has a 'compatible' property which
1036 * lists the given compatible string; or if startoffset is -1, the
1037 * very first such node in the tree.
1038 *
1039 * To iterate through all nodes matching the criterion, the following
1040 * idiom can be used:
1041 * offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
1042 * while (offset != -FDT_ERR_NOTFOUND) {
1043 * // other code here
1044 * offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
1045 * }
1046 *
1047 * Note the -1 in the first call to the function, if 0 is used here
1048 * instead, the function will never locate the root node, even if it
1049 * matches the criterion.
1050 *
1051 * returns:
1052 * structure block offset of the located node (>= 0, >startoffset),
1053 * on success
1054 * -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
1055 * tree after startoffset
1056 * -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1057 * -FDT_ERR_BADMAGIC,
1058 * -FDT_ERR_BADVERSION,
1059 * -FDT_ERR_BADSTATE,
1060 * -FDT_ERR_BADSTRUCTURE, standard meanings
1061 */
1062 int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
1063 const char *compatible);
1064
1065 /**
1066 * fdt_stringlist_contains - check a string list property for a string
1067 * @strlist: Property containing a list of strings to check
1068 * @listlen: Length of property
1069 * @str: String to search for
1070 *
1071 * This is a utility function provided for convenience. The list contains
1072 * one or more strings, each terminated by \0, as is found in a device tree
1073 * "compatible" property.
1074 *
1075 * @return: 1 if the string is found in the list, 0 not found, or invalid list
1076 */
1077 int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
1078
1079 /**
1080 * fdt_stringlist_count - count the number of strings in a string list
1081 * @fdt: pointer to the device tree blob
1082 * @nodeoffset: offset of a tree node
1083 * @property: name of the property containing the string list
1084 * @return:
1085 * the number of strings in the given property
1086 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1087 * -FDT_ERR_NOTFOUND if the property does not exist
1088 */
1089 int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property);
1090
1091 /**
1092 * fdt_stringlist_search - find a string in a string list and return its index
1093 * @fdt: pointer to the device tree blob
1094 * @nodeoffset: offset of a tree node
1095 * @property: name of the property containing the string list
1096 * @string: string to look up in the string list
1097 *
1098 * Note that it is possible for this function to succeed on property values
1099 * that are not NUL-terminated. That's because the function will stop after
1100 * finding the first occurrence of @string. This can for example happen with
1101 * small-valued cell properties, such as #address-cells, when searching for
1102 * the empty string.
1103 *
1104 * @return:
1105 * the index of the string in the list of strings
1106 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1107 * -FDT_ERR_NOTFOUND if the property does not exist or does not contain
1108 * the given string
1109 */
1110 int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
1111 const char *string);
1112
1113 /**
1114 * fdt_stringlist_get() - obtain the string at a given index in a string list
1115 * @fdt: pointer to the device tree blob
1116 * @nodeoffset: offset of a tree node
1117 * @property: name of the property containing the string list
1118 * @index: index of the string to return
1119 * @lenp: return location for the string length or an error code on failure
1120 *
1121 * Note that this will successfully extract strings from properties with
1122 * non-NUL-terminated values. For example on small-valued cell properties
1123 * this function will return the empty string.
1124 *
1125 * If non-NULL, the length of the string (on success) or a negative error-code
1126 * (on failure) will be stored in the integer pointer to by lenp.
1127 *
1128 * @return:
1129 * A pointer to the string at the given index in the string list or NULL on
1130 * failure. On success the length of the string will be stored in the memory
1131 * location pointed to by the lenp parameter, if non-NULL. On failure one of
1132 * the following negative error codes will be returned in the lenp parameter
1133 * (if non-NULL):
1134 * -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1135 * -FDT_ERR_NOTFOUND if the property does not exist
1136 */
1137 const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
1138 const char *property, int index,
1139 int *lenp);
1140
1141 /**********************************************************************/
1142 /* Read-only functions (addressing related) */
1143 /**********************************************************************/
1144
1145 /**
1146 * FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells
1147 *
1148 * This is the maximum value for #address-cells, #size-cells and
1149 * similar properties that will be processed by libfdt. IEE1275
1150 * requires that OF implementations handle values up to 4.
1151 * Implementations may support larger values, but in practice higher
1152 * values aren't used.
1153 */
1154 #define FDT_MAX_NCELLS 4
1155
1156 /**
1157 * fdt_address_cells - retrieve address size for a bus represented in the tree
1158 * @fdt: pointer to the device tree blob
1159 * @nodeoffset: offset of the node to find the address size for
1160 *
1161 * When the node has a valid #address-cells property, returns its value.
1162 *
1163 * returns:
1164 * 0 <= n < FDT_MAX_NCELLS, on success
1165 * 2, if the node has no #address-cells property
1166 * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1167 * #address-cells property
1168 * -FDT_ERR_BADMAGIC,
1169 * -FDT_ERR_BADVERSION,
1170 * -FDT_ERR_BADSTATE,
1171 * -FDT_ERR_BADSTRUCTURE,
1172 * -FDT_ERR_TRUNCATED, standard meanings
1173 */
1174 int fdt_address_cells(const void *fdt, int nodeoffset);
1175
1176 /**
1177 * fdt_size_cells - retrieve address range size for a bus represented in the
1178 * tree
1179 * @fdt: pointer to the device tree blob
1180 * @nodeoffset: offset of the node to find the address range size for
1181 *
1182 * When the node has a valid #size-cells property, returns its value.
1183 *
1184 * returns:
1185 * 0 <= n < FDT_MAX_NCELLS, on success
1186 * 1, if the node has no #size-cells property
1187 * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1188 * #size-cells property
1189 * -FDT_ERR_BADMAGIC,
1190 * -FDT_ERR_BADVERSION,
1191 * -FDT_ERR_BADSTATE,
1192 * -FDT_ERR_BADSTRUCTURE,
1193 * -FDT_ERR_TRUNCATED, standard meanings
1194 */
1195 int fdt_size_cells(const void *fdt, int nodeoffset);
1196
1197
1198 /**********************************************************************/
1199 /* Write-in-place functions */
1200 /**********************************************************************/
1201
1202 /**
1203 * fdt_setprop_inplace_namelen_partial - change a property's value,
1204 * but not its size
1205 * @fdt: pointer to the device tree blob
1206 * @nodeoffset: offset of the node whose property to change
1207 * @name: name of the property to change
1208 * @namelen: number of characters of name to consider
1209 * @idx: index of the property to change in the array
1210 * @val: pointer to data to replace the property value with
1211 * @len: length of the property value
1212 *
1213 * Identical to fdt_setprop_inplace(), but modifies the given property
1214 * starting from the given index, and using only the first characters
1215 * of the name. It is useful when you want to manipulate only one value of
1216 * an array and you have a string that doesn't end with \0.
1217 */
1218 #ifndef SWIG /* Not available in Python */
1219 int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
1220 const char *name, int namelen,
1221 uint32_t idx, const void *val,
1222 int len);
1223 #endif
1224
1225 /**
1226 * fdt_setprop_inplace - change a property's value, but not its size
1227 * @fdt: pointer to the device tree blob
1228 * @nodeoffset: offset of the node whose property to change
1229 * @name: name of the property to change
1230 * @val: pointer to data to replace the property value with
1231 * @len: length of the property value
1232 *
1233 * fdt_setprop_inplace() replaces the value of a given property with
1234 * the data in val, of length len. This function cannot change the
1235 * size of a property, and so will only work if len is equal to the
1236 * current length of the property.
1237 *
1238 * This function will alter only the bytes in the blob which contain
1239 * the given property value, and will not alter or move any other part
1240 * of the tree.
1241 *
1242 * returns:
1243 * 0, on success
1244 * -FDT_ERR_NOSPACE, if len is not equal to the property's current length
1245 * -FDT_ERR_NOTFOUND, node does not have the named property
1246 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1247 * -FDT_ERR_BADMAGIC,
1248 * -FDT_ERR_BADVERSION,
1249 * -FDT_ERR_BADSTATE,
1250 * -FDT_ERR_BADSTRUCTURE,
1251 * -FDT_ERR_TRUNCATED, standard meanings
1252 */
1253 #ifndef SWIG /* Not available in Python */
1254 int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
1255 const void *val, int len);
1256 #endif
1257
1258 /**
1259 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
1260 * @fdt: pointer to the device tree blob
1261 * @nodeoffset: offset of the node whose property to change
1262 * @name: name of the property to change
1263 * @val: 32-bit integer value to replace the property with
1264 *
1265 * fdt_setprop_inplace_u32() replaces the value of a given property
1266 * with the 32-bit integer value in val, converting val to big-endian
1267 * if necessary. This function cannot change the size of a property,
1268 * and so will only work if the property already exists and has length
1269 * 4.
1270 *
1271 * This function will alter only the bytes in the blob which contain
1272 * the given property value, and will not alter or move any other part
1273 * of the tree.
1274 *
1275 * returns:
1276 * 0, on success
1277 * -FDT_ERR_NOSPACE, if the property's length is not equal to 4
1278 * -FDT_ERR_NOTFOUND, node does not have the named property
1279 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1280 * -FDT_ERR_BADMAGIC,
1281 * -FDT_ERR_BADVERSION,
1282 * -FDT_ERR_BADSTATE,
1283 * -FDT_ERR_BADSTRUCTURE,
1284 * -FDT_ERR_TRUNCATED, standard meanings
1285 */
fdt_setprop_inplace_u32(void * fdt,int nodeoffset,const char * name,uint32_t val)1286 static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
1287 const char *name, uint32_t val)
1288 {
1289 fdt32_t tmp = cpu_to_fdt32(val);
1290 return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1291 }
1292
1293 /**
1294 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
1295 * @fdt: pointer to the device tree blob
1296 * @nodeoffset: offset of the node whose property to change
1297 * @name: name of the property to change
1298 * @val: 64-bit integer value to replace the property with
1299 *
1300 * fdt_setprop_inplace_u64() replaces the value of a given property
1301 * with the 64-bit integer value in val, converting val to big-endian
1302 * if necessary. This function cannot change the size of a property,
1303 * and so will only work if the property already exists and has length
1304 * 8.
1305 *
1306 * This function will alter only the bytes in the blob which contain
1307 * the given property value, and will not alter or move any other part
1308 * of the tree.
1309 *
1310 * returns:
1311 * 0, on success
1312 * -FDT_ERR_NOSPACE, if the property's length is not equal to 8
1313 * -FDT_ERR_NOTFOUND, node does not have the named property
1314 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1315 * -FDT_ERR_BADMAGIC,
1316 * -FDT_ERR_BADVERSION,
1317 * -FDT_ERR_BADSTATE,
1318 * -FDT_ERR_BADSTRUCTURE,
1319 * -FDT_ERR_TRUNCATED, standard meanings
1320 */
fdt_setprop_inplace_u64(void * fdt,int nodeoffset,const char * name,uint64_t val)1321 static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
1322 const char *name, uint64_t val)
1323 {
1324 fdt64_t tmp = cpu_to_fdt64(val);
1325 return fdt_setprop_inplace(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1326 }
1327
1328 /**
1329 * fdt_setprop_inplace_cell - change the value of a single-cell property
1330 *
1331 * This is an alternative name for fdt_setprop_inplace_u32()
1332 */
fdt_setprop_inplace_cell(void * fdt,int nodeoffset,const char * name,uint32_t val)1333 static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
1334 const char *name, uint32_t val)
1335 {
1336 return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
1337 }
1338
1339 /**
1340 * fdt_nop_property - replace a property with nop tags
1341 * @fdt: pointer to the device tree blob
1342 * @nodeoffset: offset of the node whose property to nop
1343 * @name: name of the property to nop
1344 *
1345 * fdt_nop_property() will replace a given property's representation
1346 * in the blob with FDT_NOP tags, effectively removing it from the
1347 * tree.
1348 *
1349 * This function will alter only the bytes in the blob which contain
1350 * the property, and will not alter or move any other part of the
1351 * tree.
1352 *
1353 * returns:
1354 * 0, on success
1355 * -FDT_ERR_NOTFOUND, node does not have the named property
1356 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1357 * -FDT_ERR_BADMAGIC,
1358 * -FDT_ERR_BADVERSION,
1359 * -FDT_ERR_BADSTATE,
1360 * -FDT_ERR_BADSTRUCTURE,
1361 * -FDT_ERR_TRUNCATED, standard meanings
1362 */
1363 int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
1364
1365 /**
1366 * fdt_nop_node - replace a node (subtree) with nop tags
1367 * @fdt: pointer to the device tree blob
1368 * @nodeoffset: offset of the node to nop
1369 *
1370 * fdt_nop_node() will replace a given node's representation in the
1371 * blob, including all its subnodes, if any, with FDT_NOP tags,
1372 * effectively removing it from the tree.
1373 *
1374 * This function will alter only the bytes in the blob which contain
1375 * the node and its properties and subnodes, and will not alter or
1376 * move any other part of the tree.
1377 *
1378 * returns:
1379 * 0, on success
1380 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1381 * -FDT_ERR_BADMAGIC,
1382 * -FDT_ERR_BADVERSION,
1383 * -FDT_ERR_BADSTATE,
1384 * -FDT_ERR_BADSTRUCTURE,
1385 * -FDT_ERR_TRUNCATED, standard meanings
1386 */
1387 int fdt_nop_node(void *fdt, int nodeoffset);
1388
1389 /**********************************************************************/
1390 /* Sequential write functions */
1391 /**********************************************************************/
1392
1393 /* fdt_create_with_flags flags */
1394 #define FDT_CREATE_FLAG_NO_NAME_DEDUP 0x1
1395 /* FDT_CREATE_FLAG_NO_NAME_DEDUP: Do not try to de-duplicate property
1396 * names in the fdt. This can result in faster creation times, but
1397 * a larger fdt. */
1398
1399 #define FDT_CREATE_FLAGS_ALL (FDT_CREATE_FLAG_NO_NAME_DEDUP)
1400
1401 /**
1402 * fdt_create_with_flags - begin creation of a new fdt
1403 * @fdt: pointer to memory allocated where fdt will be created
1404 * @bufsize: size of the memory space at fdt
1405 * @flags: a valid combination of FDT_CREATE_FLAG_ flags, or 0.
1406 *
1407 * fdt_create_with_flags() begins the process of creating a new fdt with
1408 * the sequential write interface.
1409 *
1410 * fdt creation process must end with fdt_finished() to produce a valid fdt.
1411 *
1412 * returns:
1413 * 0, on success
1414 * -FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1415 * -FDT_ERR_BADFLAGS, flags is not valid
1416 */
1417 int fdt_create_with_flags(void *buf, int bufsize, uint32_t flags);
1418
1419 /**
1420 * fdt_create - begin creation of a new fdt
1421 * @fdt: pointer to memory allocated where fdt will be created
1422 * @bufsize: size of the memory space at fdt
1423 *
1424 * fdt_create() is equivalent to fdt_create_with_flags() with flags=0.
1425 *
1426 * returns:
1427 * 0, on success
1428 * -FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1429 */
1430 int fdt_create(void *buf, int bufsize);
1431
1432 int fdt_resize(void *fdt, void *buf, int bufsize);
1433 int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
1434 int fdt_finish_reservemap(void *fdt);
1435 int fdt_begin_node(void *fdt, const char *name);
1436 int fdt_property(void *fdt, const char *name, const void *val, int len);
fdt_property_u32(void * fdt,const char * name,uint32_t val)1437 static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
1438 {
1439 fdt32_t tmp = cpu_to_fdt32(val);
1440 return fdt_property(fdt, name, &tmp, sizeof(tmp));
1441 }
fdt_property_u64(void * fdt,const char * name,uint64_t val)1442 static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
1443 {
1444 fdt64_t tmp = cpu_to_fdt64(val);
1445 return fdt_property(fdt, name, &tmp, sizeof(tmp));
1446 }
1447
1448 #ifndef SWIG /* Not available in Python */
fdt_property_cell(void * fdt,const char * name,uint32_t val)1449 static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
1450 {
1451 return fdt_property_u32(fdt, name, val);
1452 }
1453 #endif
1454
1455 /**
1456 * fdt_property_placeholder - add a new property and return a ptr to its value
1457 *
1458 * @fdt: pointer to the device tree blob
1459 * @name: name of property to add
1460 * @len: length of property value in bytes
1461 * @valp: returns a pointer to where where the value should be placed
1462 *
1463 * returns:
1464 * 0, on success
1465 * -FDT_ERR_BADMAGIC,
1466 * -FDT_ERR_NOSPACE, standard meanings
1467 */
1468 int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp);
1469
1470 #define fdt_property_string(fdt, name, str) \
1471 fdt_property(fdt, name, str, strlen(str)+1)
1472 int fdt_end_node(void *fdt);
1473 int fdt_finish(void *fdt);
1474
1475 /**********************************************************************/
1476 /* Read-write functions */
1477 /**********************************************************************/
1478
1479 int fdt_create_empty_tree(void *buf, int bufsize);
1480 int fdt_open_into(const void *fdt, void *buf, int bufsize);
1481 int fdt_pack(void *fdt);
1482
1483 /**
1484 * fdt_add_mem_rsv - add one memory reserve map entry
1485 * @fdt: pointer to the device tree blob
1486 * @address, @size: 64-bit values (native endian)
1487 *
1488 * Adds a reserve map entry to the given blob reserving a region at
1489 * address address of length size.
1490 *
1491 * This function will insert data into the reserve map and will
1492 * therefore change the indexes of some entries in the table.
1493 *
1494 * returns:
1495 * 0, on success
1496 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1497 * contain the new reservation entry
1498 * -FDT_ERR_BADMAGIC,
1499 * -FDT_ERR_BADVERSION,
1500 * -FDT_ERR_BADSTATE,
1501 * -FDT_ERR_BADSTRUCTURE,
1502 * -FDT_ERR_BADLAYOUT,
1503 * -FDT_ERR_TRUNCATED, standard meanings
1504 */
1505 int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
1506
1507 /**
1508 * fdt_del_mem_rsv - remove a memory reserve map entry
1509 * @fdt: pointer to the device tree blob
1510 * @n: entry to remove
1511 *
1512 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
1513 * the blob.
1514 *
1515 * This function will delete data from the reservation table and will
1516 * therefore change the indexes of some entries in the table.
1517 *
1518 * returns:
1519 * 0, on success
1520 * -FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
1521 * are less than n+1 reserve map entries)
1522 * -FDT_ERR_BADMAGIC,
1523 * -FDT_ERR_BADVERSION,
1524 * -FDT_ERR_BADSTATE,
1525 * -FDT_ERR_BADSTRUCTURE,
1526 * -FDT_ERR_BADLAYOUT,
1527 * -FDT_ERR_TRUNCATED, standard meanings
1528 */
1529 int fdt_del_mem_rsv(void *fdt, int n);
1530
1531 /**
1532 * fdt_set_name - change the name of a given node
1533 * @fdt: pointer to the device tree blob
1534 * @nodeoffset: structure block offset of a node
1535 * @name: name to give the node
1536 *
1537 * fdt_set_name() replaces the name (including unit address, if any)
1538 * of the given node with the given string. NOTE: this function can't
1539 * efficiently check if the new name is unique amongst the given
1540 * node's siblings; results are undefined if this function is invoked
1541 * with a name equal to one of the given node's siblings.
1542 *
1543 * This function may insert or delete data from the blob, and will
1544 * therefore change the offsets of some existing nodes.
1545 *
1546 * returns:
1547 * 0, on success
1548 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob
1549 * to contain the new name
1550 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1551 * -FDT_ERR_BADMAGIC,
1552 * -FDT_ERR_BADVERSION,
1553 * -FDT_ERR_BADSTATE, standard meanings
1554 */
1555 int fdt_set_name(void *fdt, int nodeoffset, const char *name);
1556
1557 /**
1558 * fdt_setprop - create or change a property
1559 * @fdt: pointer to the device tree blob
1560 * @nodeoffset: offset of the node whose property to change
1561 * @name: name of the property to change
1562 * @val: pointer to data to set the property value to
1563 * @len: length of the property value
1564 *
1565 * fdt_setprop() sets the value of the named property in the given
1566 * node to the given value and length, creating the property if it
1567 * does not already exist.
1568 *
1569 * This function may insert or delete data from the blob, and will
1570 * therefore change the offsets of some existing nodes.
1571 *
1572 * returns:
1573 * 0, on success
1574 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1575 * contain the new property value
1576 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1577 * -FDT_ERR_BADLAYOUT,
1578 * -FDT_ERR_BADMAGIC,
1579 * -FDT_ERR_BADVERSION,
1580 * -FDT_ERR_BADSTATE,
1581 * -FDT_ERR_BADSTRUCTURE,
1582 * -FDT_ERR_BADLAYOUT,
1583 * -FDT_ERR_TRUNCATED, standard meanings
1584 */
1585 int fdt_setprop(void *fdt, int nodeoffset, const char *name,
1586 const void *val, int len);
1587
1588 /**
1589 * fdt_setprop_placeholder - allocate space for a property
1590 * @fdt: pointer to the device tree blob
1591 * @nodeoffset: offset of the node whose property to change
1592 * @name: name of the property to change
1593 * @len: length of the property value
1594 * @prop_data: return pointer to property data
1595 *
1596 * fdt_setprop_placeholer() allocates the named property in the given node.
1597 * If the property exists it is resized. In either case a pointer to the
1598 * property data is returned.
1599 *
1600 * This function may insert or delete data from the blob, and will
1601 * therefore change the offsets of some existing nodes.
1602 *
1603 * returns:
1604 * 0, on success
1605 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1606 * contain the new property value
1607 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1608 * -FDT_ERR_BADLAYOUT,
1609 * -FDT_ERR_BADMAGIC,
1610 * -FDT_ERR_BADVERSION,
1611 * -FDT_ERR_BADSTATE,
1612 * -FDT_ERR_BADSTRUCTURE,
1613 * -FDT_ERR_BADLAYOUT,
1614 * -FDT_ERR_TRUNCATED, standard meanings
1615 */
1616 int fdt_setprop_placeholder(void *fdt, int nodeoffset, const char *name,
1617 int len, void **prop_data);
1618
1619 /**
1620 * fdt_setprop_u32 - set a property to a 32-bit integer
1621 * @fdt: pointer to the device tree blob
1622 * @nodeoffset: offset of the node whose property to change
1623 * @name: name of the property to change
1624 * @val: 32-bit integer value for the property (native endian)
1625 *
1626 * fdt_setprop_u32() sets the value of the named property in the given
1627 * node to the given 32-bit integer value (converting to big-endian if
1628 * necessary), or creates a new property with that value if it does
1629 * not already exist.
1630 *
1631 * This function may insert or delete data from the blob, and will
1632 * therefore change the offsets of some existing nodes.
1633 *
1634 * returns:
1635 * 0, on success
1636 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1637 * contain the new property value
1638 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1639 * -FDT_ERR_BADLAYOUT,
1640 * -FDT_ERR_BADMAGIC,
1641 * -FDT_ERR_BADVERSION,
1642 * -FDT_ERR_BADSTATE,
1643 * -FDT_ERR_BADSTRUCTURE,
1644 * -FDT_ERR_BADLAYOUT,
1645 * -FDT_ERR_TRUNCATED, standard meanings
1646 */
fdt_setprop_u32(void * fdt,int nodeoffset,const char * name,uint32_t val)1647 static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
1648 uint32_t val)
1649 {
1650 fdt32_t tmp = cpu_to_fdt32(val);
1651 return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1652 }
1653
1654 /**
1655 * fdt_setprop_u64 - set a property to a 64-bit integer
1656 * @fdt: pointer to the device tree blob
1657 * @nodeoffset: offset of the node whose property to change
1658 * @name: name of the property to change
1659 * @val: 64-bit integer value for the property (native endian)
1660 *
1661 * fdt_setprop_u64() sets the value of the named property in the given
1662 * node to the given 64-bit integer value (converting to big-endian if
1663 * necessary), or creates a new property with that value if it does
1664 * not already exist.
1665 *
1666 * This function may insert or delete data from the blob, and will
1667 * therefore change the offsets of some existing nodes.
1668 *
1669 * returns:
1670 * 0, on success
1671 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1672 * contain the new property value
1673 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1674 * -FDT_ERR_BADLAYOUT,
1675 * -FDT_ERR_BADMAGIC,
1676 * -FDT_ERR_BADVERSION,
1677 * -FDT_ERR_BADSTATE,
1678 * -FDT_ERR_BADSTRUCTURE,
1679 * -FDT_ERR_BADLAYOUT,
1680 * -FDT_ERR_TRUNCATED, standard meanings
1681 */
fdt_setprop_u64(void * fdt,int nodeoffset,const char * name,uint64_t val)1682 static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
1683 uint64_t val)
1684 {
1685 fdt64_t tmp = cpu_to_fdt64(val);
1686 return fdt_setprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1687 }
1688
1689 /**
1690 * fdt_setprop_cell - set a property to a single cell value
1691 *
1692 * This is an alternative name for fdt_setprop_u32()
1693 */
fdt_setprop_cell(void * fdt,int nodeoffset,const char * name,uint32_t val)1694 static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
1695 uint32_t val)
1696 {
1697 return fdt_setprop_u32(fdt, nodeoffset, name, val);
1698 }
1699
1700 /**
1701 * fdt_setprop_string - set a property to a string value
1702 * @fdt: pointer to the device tree blob
1703 * @nodeoffset: offset of the node whose property to change
1704 * @name: name of the property to change
1705 * @str: string value for the property
1706 *
1707 * fdt_setprop_string() sets the value of the named property in the
1708 * given node to the given string value (using the length of the
1709 * string to determine the new length of the property), or creates a
1710 * new property with that value if it does not already exist.
1711 *
1712 * This function may insert or delete data from the blob, and will
1713 * therefore change the offsets of some existing nodes.
1714 *
1715 * returns:
1716 * 0, on success
1717 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1718 * contain the new property value
1719 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1720 * -FDT_ERR_BADLAYOUT,
1721 * -FDT_ERR_BADMAGIC,
1722 * -FDT_ERR_BADVERSION,
1723 * -FDT_ERR_BADSTATE,
1724 * -FDT_ERR_BADSTRUCTURE,
1725 * -FDT_ERR_BADLAYOUT,
1726 * -FDT_ERR_TRUNCATED, standard meanings
1727 */
1728 #define fdt_setprop_string(fdt, nodeoffset, name, str) \
1729 fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1730
1731
1732 /**
1733 * fdt_setprop_empty - set a property to an empty value
1734 * @fdt: pointer to the device tree blob
1735 * @nodeoffset: offset of the node whose property to change
1736 * @name: name of the property to change
1737 *
1738 * fdt_setprop_empty() sets the value of the named property in the
1739 * given node to an empty (zero length) value, or creates a new empty
1740 * property if it does not already exist.
1741 *
1742 * This function may insert or delete data from the blob, and will
1743 * therefore change the offsets of some existing nodes.
1744 *
1745 * returns:
1746 * 0, on success
1747 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1748 * contain the new property value
1749 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1750 * -FDT_ERR_BADLAYOUT,
1751 * -FDT_ERR_BADMAGIC,
1752 * -FDT_ERR_BADVERSION,
1753 * -FDT_ERR_BADSTATE,
1754 * -FDT_ERR_BADSTRUCTURE,
1755 * -FDT_ERR_BADLAYOUT,
1756 * -FDT_ERR_TRUNCATED, standard meanings
1757 */
1758 #define fdt_setprop_empty(fdt, nodeoffset, name) \
1759 fdt_setprop((fdt), (nodeoffset), (name), NULL, 0)
1760
1761 /**
1762 * fdt_appendprop - append to or create a property
1763 * @fdt: pointer to the device tree blob
1764 * @nodeoffset: offset of the node whose property to change
1765 * @name: name of the property to append to
1766 * @val: pointer to data to append to the property value
1767 * @len: length of the data to append to the property value
1768 *
1769 * fdt_appendprop() appends the value to the named property in the
1770 * given node, creating the property if it does not already exist.
1771 *
1772 * This function may insert data into the blob, and will therefore
1773 * change the offsets of some existing nodes.
1774 *
1775 * returns:
1776 * 0, on success
1777 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1778 * contain the new property value
1779 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1780 * -FDT_ERR_BADLAYOUT,
1781 * -FDT_ERR_BADMAGIC,
1782 * -FDT_ERR_BADVERSION,
1783 * -FDT_ERR_BADSTATE,
1784 * -FDT_ERR_BADSTRUCTURE,
1785 * -FDT_ERR_BADLAYOUT,
1786 * -FDT_ERR_TRUNCATED, standard meanings
1787 */
1788 int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
1789 const void *val, int len);
1790
1791 /**
1792 * fdt_appendprop_u32 - append a 32-bit integer value to a property
1793 * @fdt: pointer to the device tree blob
1794 * @nodeoffset: offset of the node whose property to change
1795 * @name: name of the property to change
1796 * @val: 32-bit integer value to append to the property (native endian)
1797 *
1798 * fdt_appendprop_u32() appends the given 32-bit integer value
1799 * (converting to big-endian if necessary) to the value of the named
1800 * property in the given node, or creates a new property with that
1801 * value if it does not already exist.
1802 *
1803 * This function may insert data into the blob, and will therefore
1804 * change the offsets of some existing nodes.
1805 *
1806 * returns:
1807 * 0, on success
1808 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1809 * contain the new property value
1810 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1811 * -FDT_ERR_BADLAYOUT,
1812 * -FDT_ERR_BADMAGIC,
1813 * -FDT_ERR_BADVERSION,
1814 * -FDT_ERR_BADSTATE,
1815 * -FDT_ERR_BADSTRUCTURE,
1816 * -FDT_ERR_BADLAYOUT,
1817 * -FDT_ERR_TRUNCATED, standard meanings
1818 */
fdt_appendprop_u32(void * fdt,int nodeoffset,const char * name,uint32_t val)1819 static inline int fdt_appendprop_u32(void *fdt, int nodeoffset,
1820 const char *name, uint32_t val)
1821 {
1822 fdt32_t tmp = cpu_to_fdt32(val);
1823 return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1824 }
1825
1826 /**
1827 * fdt_appendprop_u64 - append a 64-bit integer value to a property
1828 * @fdt: pointer to the device tree blob
1829 * @nodeoffset: offset of the node whose property to change
1830 * @name: name of the property to change
1831 * @val: 64-bit integer value to append to the property (native endian)
1832 *
1833 * fdt_appendprop_u64() appends the given 64-bit integer value
1834 * (converting to big-endian if necessary) to the value of the named
1835 * property in the given node, or creates a new property with that
1836 * value if it does not already exist.
1837 *
1838 * This function may insert data into the blob, and will therefore
1839 * change the offsets of some existing nodes.
1840 *
1841 * returns:
1842 * 0, on success
1843 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1844 * contain the new property value
1845 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1846 * -FDT_ERR_BADLAYOUT,
1847 * -FDT_ERR_BADMAGIC,
1848 * -FDT_ERR_BADVERSION,
1849 * -FDT_ERR_BADSTATE,
1850 * -FDT_ERR_BADSTRUCTURE,
1851 * -FDT_ERR_BADLAYOUT,
1852 * -FDT_ERR_TRUNCATED, standard meanings
1853 */
fdt_appendprop_u64(void * fdt,int nodeoffset,const char * name,uint64_t val)1854 static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
1855 const char *name, uint64_t val)
1856 {
1857 fdt64_t tmp = cpu_to_fdt64(val);
1858 return fdt_appendprop(fdt, nodeoffset, name, &tmp, sizeof(tmp));
1859 }
1860
1861 /**
1862 * fdt_appendprop_cell - append a single cell value to a property
1863 *
1864 * This is an alternative name for fdt_appendprop_u32()
1865 */
fdt_appendprop_cell(void * fdt,int nodeoffset,const char * name,uint32_t val)1866 static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
1867 const char *name, uint32_t val)
1868 {
1869 return fdt_appendprop_u32(fdt, nodeoffset, name, val);
1870 }
1871
1872 /**
1873 * fdt_appendprop_string - append a string to a property
1874 * @fdt: pointer to the device tree blob
1875 * @nodeoffset: offset of the node whose property to change
1876 * @name: name of the property to change
1877 * @str: string value to append to the property
1878 *
1879 * fdt_appendprop_string() appends the given string to the value of
1880 * the named property in the given node, or creates a new property
1881 * with that value if it does not already exist.
1882 *
1883 * This function may insert data into the blob, and will therefore
1884 * change the offsets of some existing nodes.
1885 *
1886 * returns:
1887 * 0, on success
1888 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1889 * contain the new property value
1890 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1891 * -FDT_ERR_BADLAYOUT,
1892 * -FDT_ERR_BADMAGIC,
1893 * -FDT_ERR_BADVERSION,
1894 * -FDT_ERR_BADSTATE,
1895 * -FDT_ERR_BADSTRUCTURE,
1896 * -FDT_ERR_BADLAYOUT,
1897 * -FDT_ERR_TRUNCATED, standard meanings
1898 */
1899 #define fdt_appendprop_string(fdt, nodeoffset, name, str) \
1900 fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1901
1902 /**
1903 * fdt_appendprop_addrrange - append a address range property
1904 * @fdt: pointer to the device tree blob
1905 * @parent: offset of the parent node
1906 * @nodeoffset: offset of the node to add a property at
1907 * @name: name of property
1908 * @addr: start address of a given range
1909 * @size: size of a given range
1910 *
1911 * fdt_appendprop_addrrange() appends an address range value (start
1912 * address and size) to the value of the named property in the given
1913 * node, or creates a new property with that value if it does not
1914 * already exist.
1915 * If "name" is not specified, a default "reg" is used.
1916 * Cell sizes are determined by parent's #address-cells and #size-cells.
1917 *
1918 * This function may insert data into the blob, and will therefore
1919 * change the offsets of some existing nodes.
1920 *
1921 * returns:
1922 * 0, on success
1923 * -FDT_ERR_BADLAYOUT,
1924 * -FDT_ERR_BADMAGIC,
1925 * -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1926 * #address-cells property
1927 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1928 * -FDT_ERR_BADSTATE,
1929 * -FDT_ERR_BADSTRUCTURE,
1930 * -FDT_ERR_BADVERSION,
1931 * -FDT_ERR_BADVALUE, addr or size doesn't fit to respective cells size
1932 * -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1933 * contain a new property
1934 * -FDT_ERR_TRUNCATED, standard meanings
1935 */
1936 int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
1937 const char *name, uint64_t addr, uint64_t size);
1938
1939 /**
1940 * fdt_delprop - delete a property
1941 * @fdt: pointer to the device tree blob
1942 * @nodeoffset: offset of the node whose property to nop
1943 * @name: name of the property to nop
1944 *
1945 * fdt_del_property() will delete the given property.
1946 *
1947 * This function will delete data from the blob, and will therefore
1948 * change the offsets of some existing nodes.
1949 *
1950 * returns:
1951 * 0, on success
1952 * -FDT_ERR_NOTFOUND, node does not have the named property
1953 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1954 * -FDT_ERR_BADLAYOUT,
1955 * -FDT_ERR_BADMAGIC,
1956 * -FDT_ERR_BADVERSION,
1957 * -FDT_ERR_BADSTATE,
1958 * -FDT_ERR_BADSTRUCTURE,
1959 * -FDT_ERR_TRUNCATED, standard meanings
1960 */
1961 int fdt_delprop(void *fdt, int nodeoffset, const char *name);
1962
1963 /**
1964 * fdt_add_subnode_namelen - creates a new node based on substring
1965 * @fdt: pointer to the device tree blob
1966 * @parentoffset: structure block offset of a node
1967 * @name: name of the subnode to locate
1968 * @namelen: number of characters of name to consider
1969 *
1970 * Identical to fdt_add_subnode(), but use only the first namelen
1971 * characters of name as the name of the new node. This is useful for
1972 * creating subnodes based on a portion of a larger string, such as a
1973 * full path.
1974 */
1975 #ifndef SWIG /* Not available in Python */
1976 int fdt_add_subnode_namelen(void *fdt, int parentoffset,
1977 const char *name, int namelen);
1978 #endif
1979
1980 /**
1981 * fdt_add_subnode - creates a new node
1982 * @fdt: pointer to the device tree blob
1983 * @parentoffset: structure block offset of a node
1984 * @name: name of the subnode to locate
1985 *
1986 * fdt_add_subnode() creates a new node as a subnode of the node at
1987 * structure block offset parentoffset, with the given name (which
1988 * should include the unit address, if any).
1989 *
1990 * This function will insert data into the blob, and will therefore
1991 * change the offsets of some existing nodes.
1992
1993 * returns:
1994 * structure block offset of the created nodeequested subnode (>=0), on
1995 * success
1996 * -FDT_ERR_NOTFOUND, if the requested subnode does not exist
1997 * -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
1998 * tag
1999 * -FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
2000 * the given name
2001 * -FDT_ERR_NOSPACE, if there is insufficient free space in the
2002 * blob to contain the new node
2003 * -FDT_ERR_NOSPACE
2004 * -FDT_ERR_BADLAYOUT
2005 * -FDT_ERR_BADMAGIC,
2006 * -FDT_ERR_BADVERSION,
2007 * -FDT_ERR_BADSTATE,
2008 * -FDT_ERR_BADSTRUCTURE,
2009 * -FDT_ERR_TRUNCATED, standard meanings.
2010 */
2011 int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
2012
2013 /**
2014 * fdt_del_node - delete a node (subtree)
2015 * @fdt: pointer to the device tree blob
2016 * @nodeoffset: offset of the node to nop
2017 *
2018 * fdt_del_node() will remove the given node, including all its
2019 * subnodes if any, from the blob.
2020 *
2021 * This function will delete data from the blob, and will therefore
2022 * change the offsets of some existing nodes.
2023 *
2024 * returns:
2025 * 0, on success
2026 * -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2027 * -FDT_ERR_BADLAYOUT,
2028 * -FDT_ERR_BADMAGIC,
2029 * -FDT_ERR_BADVERSION,
2030 * -FDT_ERR_BADSTATE,
2031 * -FDT_ERR_BADSTRUCTURE,
2032 * -FDT_ERR_TRUNCATED, standard meanings
2033 */
2034 int fdt_del_node(void *fdt, int nodeoffset);
2035
2036 /**
2037 * fdt_overlay_apply - Applies a DT overlay on a base DT
2038 * @fdt: pointer to the base device tree blob
2039 * @fdto: pointer to the device tree overlay blob
2040 *
2041 * fdt_overlay_apply() will apply the given device tree overlay on the
2042 * given base device tree.
2043 *
2044 * Expect the base device tree to be modified, even if the function
2045 * returns an error.
2046 *
2047 * returns:
2048 * 0, on success
2049 * -FDT_ERR_NOSPACE, there's not enough space in the base device tree
2050 * -FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
2051 * properties in the base DT
2052 * -FDT_ERR_BADPHANDLE,
2053 * -FDT_ERR_BADOVERLAY,
2054 * -FDT_ERR_NOPHANDLES,
2055 * -FDT_ERR_INTERNAL,
2056 * -FDT_ERR_BADLAYOUT,
2057 * -FDT_ERR_BADMAGIC,
2058 * -FDT_ERR_BADOFFSET,
2059 * -FDT_ERR_BADPATH,
2060 * -FDT_ERR_BADVERSION,
2061 * -FDT_ERR_BADSTRUCTURE,
2062 * -FDT_ERR_BADSTATE,
2063 * -FDT_ERR_TRUNCATED, standard meanings
2064 */
2065 int fdt_overlay_apply(void *fdt, void *fdto);
2066
2067 /**********************************************************************/
2068 /* Debugging / informational functions */
2069 /**********************************************************************/
2070
2071 const char *fdt_strerror(int errval);
2072
2073 #endif /* LIBFDT_H */
2074