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
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	*/
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
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
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
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
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	*/
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: &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	* If the path is not absolute (i.e. does not begin with '/'), the
528	* first component is treated as an alias. That is, the property by
529	* that name is looked up in the /aliases node, and the value of that
530	* property used in place of that first component.
531	*
532	* For example, for this small fragment
533	*
534	* / {
535	* aliases {
536	* i2c2 = &foo; // RHS compiles to "/soc@0/i2c@30a40000/eeprom@52"
537	* };
538	* soc@0 {
539	* foo: i2c@30a40000 {
540	* bar: eeprom@52 {
541	* };
542	* };
543	* };
544	* };
545	*
546	* these would be equivalent:
547	*
548	* /soc@0/i2c@30a40000/eeprom@52
549	* i2c2/eeprom@52
550	*
551	* returns:
552	* structure block offset of the node with the requested path (>=0), on
553	* success
554	* -FDT_ERR_BADPATH, given path does not begin with '/' and the first
555	* component is not a valid alias
556	* -FDT_ERR_NOTFOUND, if the requested node does not exist
557	* -FDT_ERR_BADMAGIC,
558	* -FDT_ERR_BADVERSION,
559	* -FDT_ERR_BADSTATE,
560	* -FDT_ERR_BADSTRUCTURE,
561	* -FDT_ERR_TRUNCATED, standard meanings.
562	*/
563	int fdt_path_offset(const void *fdt, const char *path);
564
565	/**
566	* fdt_get_name - retrieve the name of a given node
567	* @fdt: pointer to the device tree blob
568	* @nodeoffset: structure block offset of the starting node
569	* @lenp: pointer to an integer variable (will be overwritten) or NULL
570	*
571	* fdt_get_name() retrieves the name (including unit address) of the
572	* device tree node at structure block offset nodeoffset. If lenp is
573	* non-NULL, the length of this name is also returned, in the integer
574	* pointed to by lenp.
575	*
576	* returns:
577	* pointer to the node's name, on success
578	* If lenp is non-NULL, *lenp contains the length of that name
579	* (>=0)
580	* NULL, on error
581	* if lenp is non-NULL *lenp contains an error code (<0):
582	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
583	* tag
584	* -FDT_ERR_BADMAGIC,
585	* -FDT_ERR_BADVERSION,
586	* -FDT_ERR_BADSTATE, standard meanings
587	*/
588	const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);
589
590	/**
591	* fdt_first_property_offset - find the offset of a node's first property
592	* @fdt: pointer to the device tree blob
593	* @nodeoffset: structure block offset of a node
594	*
595	* fdt_first_property_offset() finds the first property of the node at
596	* the given structure block offset.
597	*
598	* returns:
599	* structure block offset of the property (>=0), on success
600	* -FDT_ERR_NOTFOUND, if the requested node has no properties
601	* -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
602	* -FDT_ERR_BADMAGIC,
603	* -FDT_ERR_BADVERSION,
604	* -FDT_ERR_BADSTATE,
605	* -FDT_ERR_BADSTRUCTURE,
606	* -FDT_ERR_TRUNCATED, standard meanings.
607	*/
608	int fdt_first_property_offset(const void *fdt, int nodeoffset);
609
610	/**
611	* fdt_next_property_offset - step through a node's properties
612	* @fdt: pointer to the device tree blob
613	* @offset: structure block offset of a property
614	*
615	* fdt_next_property_offset() finds the property immediately after the
616	* one at the given structure block offset. This will be a property
617	* of the same node as the given property.
618	*
619	* returns:
620	* structure block offset of the next property (>=0), on success
621	* -FDT_ERR_NOTFOUND, if the given property is the last in its node
622	* -FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag
623	* -FDT_ERR_BADMAGIC,
624	* -FDT_ERR_BADVERSION,
625	* -FDT_ERR_BADSTATE,
626	* -FDT_ERR_BADSTRUCTURE,
627	* -FDT_ERR_TRUNCATED, standard meanings.
628	*/
629	int fdt_next_property_offset(const void *fdt, int offset);
630
631	/**
632	* fdt_for_each_property_offset - iterate over all properties of a node
633	*
634	* @property: property offset (int, lvalue)
635	* @fdt: FDT blob (const void *)
636	* @node: node offset (int)
637	*
638	* This is actually a wrapper around a for loop and would be used like so:
639	*
640	* fdt_for_each_property_offset(property, fdt, node) {
641	* Use property
642	* ...
643	* }
644	*
645	* if ((property < 0) && (property != -FDT_ERR_NOTFOUND)) {
646	* Error handling
647	* }
648	*
649	* Note that this is implemented as a macro and property is used as
650	* iterator in the loop. The node variable can be constant or even a
651	* literal.
652	*/
653	#define fdt_for_each_property_offset(property, fdt, node) \
654	for (property = fdt_first_property_offset(fdt, node); \
655	property >= 0; \
656	property = fdt_next_property_offset(fdt, property))
657
658	/**
659	* fdt_get_property_by_offset - retrieve the property at a given offset
660	* @fdt: pointer to the device tree blob
661	* @offset: offset of the property to retrieve
662	* @lenp: pointer to an integer variable (will be overwritten) or NULL
663	*
664	* fdt_get_property_by_offset() retrieves a pointer to the
665	* fdt_property structure within the device tree blob at the given
666	* offset. If lenp is non-NULL, the length of the property value is
667	* also returned, in the integer pointed to by lenp.
668	*
669	* Note that this code only works on device tree versions >= 16. fdt_getprop()
670	* works on all versions.
671	*
672	* returns:
673	* pointer to the structure representing the property
674	* if lenp is non-NULL, *lenp contains the length of the property
675	* value (>=0)
676	* NULL, on error
677	* if lenp is non-NULL, *lenp contains an error code (<0):
678	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
679	* -FDT_ERR_BADMAGIC,
680	* -FDT_ERR_BADVERSION,
681	* -FDT_ERR_BADSTATE,
682	* -FDT_ERR_BADSTRUCTURE,
683	* -FDT_ERR_TRUNCATED, standard meanings
684	*/
685	const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
686	int offset,
687	int *lenp);
688	static inline struct fdt_property *fdt_get_property_by_offset_w(void *fdt,
689	int offset,
690	int *lenp)
691	{
692	return (struct fdt_property *)(uintptr_t)
693	fdt_get_property_by_offset(fdt, offset, lenp);
694	}
695
696	/**
697	* fdt_get_property_namelen - find a property based on substring
698	* @fdt: pointer to the device tree blob
699	* @nodeoffset: offset of the node whose property to find
700	* @name: name of the property to find
701	* @namelen: number of characters of name to consider
702	* @lenp: pointer to an integer variable (will be overwritten) or NULL
703	*
704	* Identical to fdt_get_property(), but only examine the first namelen
705	* characters of name for matching the property name.
706	*
707	* Return: pointer to the structure representing the property, or NULL
708	* if not found
709	*/
710	#ifndef SWIG /* Not available in Python */
711	const struct fdt_property *fdt_get_property_namelen(const void *fdt,
712	int nodeoffset,
713	const char *name,
714	int namelen, int *lenp);
715	#endif
716
717	/**
718	* fdt_get_property - find a given property in a given node
719	* @fdt: pointer to the device tree blob
720	* @nodeoffset: offset of the node whose property to find
721	* @name: name of the property to find
722	* @lenp: pointer to an integer variable (will be overwritten) or NULL
723	*
724	* fdt_get_property() retrieves a pointer to the fdt_property
725	* structure within the device tree blob corresponding to the property
726	* named 'name' of the node at offset nodeoffset. If lenp is
727	* non-NULL, the length of the property value is also returned, in the
728	* integer pointed to by lenp.
729	*
730	* returns:
731	* pointer to the structure representing the property
732	* if lenp is non-NULL, *lenp contains the length of the property
733	* value (>=0)
734	* NULL, on error
735	* if lenp is non-NULL, *lenp contains an error code (<0):
736	* -FDT_ERR_NOTFOUND, node does not have named property
737	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
738	* tag
739	* -FDT_ERR_BADMAGIC,
740	* -FDT_ERR_BADVERSION,
741	* -FDT_ERR_BADSTATE,
742	* -FDT_ERR_BADSTRUCTURE,
743	* -FDT_ERR_TRUNCATED, standard meanings
744	*/
745	const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
746	const char *name, int *lenp);
747	static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
748	const char *name,
749	int *lenp)
750	{
751	return (struct fdt_property *)(uintptr_t)
752	fdt_get_property(fdt, nodeoffset, name, lenp);
753	}
754
755	/**
756	* fdt_getprop_by_offset - retrieve the value of a property at a given offset
757	* @fdt: pointer to the device tree blob
758	* @offset: offset of the property to read
759	* @namep: pointer to a string variable (will be overwritten) or NULL
760	* @lenp: pointer to an integer variable (will be overwritten) or NULL
761	*
762	* fdt_getprop_by_offset() retrieves a pointer to the value of the
763	* property at structure block offset 'offset' (this will be a pointer
764	* to within the device blob itself, not a copy of the value). If
765	* lenp is non-NULL, the length of the property value is also
766	* returned, in the integer pointed to by lenp. If namep is non-NULL,
767	* the property's namne will also be returned in the char * pointed to
768	* by namep (this will be a pointer to within the device tree's string
769	* block, not a new copy of the name).
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	* if namep is non-NULL *namep contiains a pointer to the property
776	* name.
777	* NULL, on error
778	* if lenp is non-NULL, *lenp contains an error code (<0):
779	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP 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	#ifndef SWIG /* This function is not useful in Python */
787	const void *fdt_getprop_by_offset(const void *fdt, int offset,
788	const char **namep, int *lenp);
789	#endif
790
791	/**
792	* fdt_getprop_namelen - get property value based on substring
793	* @fdt: pointer to the device tree blob
794	* @nodeoffset: offset of the node whose property to find
795	* @name: name of the property to find
796	* @namelen: number of characters of name to consider
797	* @lenp: pointer to an integer variable (will be overwritten) or NULL
798	*
799	* Identical to fdt_getprop(), but only examine the first namelen
800	* characters of name for matching the property name.
801	*
802	* Return: pointer to the property's value or NULL on error
803	*/
804	#ifndef SWIG /* Not available in Python */
805	const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
806	const char *name, int namelen, int *lenp);
807	static inline void *fdt_getprop_namelen_w(void *fdt, int nodeoffset,
808	const char *name, int namelen,
809	int *lenp)
810	{
811	return (void *)(uintptr_t)fdt_getprop_namelen(fdt, nodeoffset, name,
812	namelen, lenp);
813	}
814	#endif
815
816	/**
817	* fdt_getprop - retrieve the value of a given property
818	* @fdt: pointer to the device tree blob
819	* @nodeoffset: offset of the node whose property to find
820	* @name: name of the property to find
821	* @lenp: pointer to an integer variable (will be overwritten) or NULL
822	*
823	* fdt_getprop() retrieves a pointer to the value of the property
824	* named @name of the node at offset @nodeoffset (this will be a
825	* pointer to within the device blob itself, not a copy of the value).
826	* If @lenp is non-NULL, the length of the property value is also
827	* returned, in the integer pointed to by @lenp.
828	*
829	* returns:
830	* pointer to the property's value
831	* if lenp is non-NULL, *lenp contains the length of the property
832	* value (>=0)
833	* NULL, on error
834	* if lenp is non-NULL, *lenp contains an error code (<0):
835	* -FDT_ERR_NOTFOUND, node does not have named property
836	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE
837	* tag
838	* -FDT_ERR_BADMAGIC,
839	* -FDT_ERR_BADVERSION,
840	* -FDT_ERR_BADSTATE,
841	* -FDT_ERR_BADSTRUCTURE,
842	* -FDT_ERR_TRUNCATED, standard meanings
843	*/
844	const void *fdt_getprop(const void *fdt, int nodeoffset,
845	const char *name, int *lenp);
846	static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
847	const char *name, int *lenp)
848	{
849	return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
850	}
851
852	/**
853	* fdt_get_phandle - retrieve the phandle of a given node
854	* @fdt: pointer to the device tree blob
855	* @nodeoffset: structure block offset of the node
856	*
857	* fdt_get_phandle() retrieves the phandle of the device tree node at
858	* structure block offset nodeoffset.
859	*
860	* returns:
861	* the phandle of the node at nodeoffset, on success (!= 0, != -1)
862	* 0, if the node has no phandle, or another error occurs
863	*/
864	uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);
865
866	/**
867	* fdt_get_alias_namelen - get alias based on substring
868	* @fdt: pointer to the device tree blob
869	* @name: name of the alias th look up
870	* @namelen: number of characters of name to consider
871	*
872	* Identical to fdt_get_alias(), but only examine the first @namelen
873	* characters of @name for matching the alias name.
874	*
875	* Return: a pointer to the expansion of the alias named @name, if it exists,
876	* NULL otherwise
877	*/
878	#ifndef SWIG /* Not available in Python */
879	const char *fdt_get_alias_namelen(const void *fdt,
880	const char *name, int namelen);
881	#endif
882
883	/**
884	* fdt_get_alias - retrieve the path referenced by a given alias
885	* @fdt: pointer to the device tree blob
886	* @name: name of the alias th look up
887	*
888	* fdt_get_alias() retrieves the value of a given alias. That is, the
889	* value of the property named @name in the node /aliases.
890	*
891	* returns:
892	* a pointer to the expansion of the alias named 'name', if it exists
893	* NULL, if the given alias or the /aliases node does not exist
894	*/
895	const char *fdt_get_alias(const void *fdt, const char *name);
896
897	/**
898	* fdt_get_symbol_namelen - get symbol based on substring
899	* @fdt: pointer to the device tree blob
900	* @name: name of the symbol to look up
901	* @namelen: number of characters of name to consider
902	*
903	* Identical to fdt_get_symbol(), but only examine the first @namelen
904	* characters of @name for matching the symbol name.
905	*
906	* Return: a pointer to the expansion of the symbol named @name, if it exists,
907	* NULL otherwise
908	*/
909	#ifndef SWIG /* Not available in Python */
910	const char *fdt_get_symbol_namelen(const void *fdt,
911	const char *name, int namelen);
912	#endif
913
914	/**
915	* fdt_get_symbol - retrieve the path referenced by a given symbol
916	* @fdt: pointer to the device tree blob
917	* @name: name of the symbol to look up
918	*
919	* fdt_get_symbol() retrieves the value of a given symbol. That is,
920	* the value of the property named @name in the node
921	* /__symbols__. Such a node exists only for a device tree blob that
922	* has been compiled with the -@ dtc option. Each property corresponds
923	* to a label appearing in the device tree source, with the name of
924	* the property being the label and the value being the full path of
925	* the node it is attached to.
926	*
927	* returns:
928	* a pointer to the expansion of the symbol named 'name', if it exists
929	* NULL, if the given symbol or the /__symbols__ node does not exist
930	*/
931	const char *fdt_get_symbol(const void *fdt, const char *name);
932
933	/**
934	* fdt_get_path - determine the full path of a node
935	* @fdt: pointer to the device tree blob
936	* @nodeoffset: offset of the node whose path to find
937	* @buf: character buffer to contain the returned path (will be overwritten)
938	* @buflen: size of the character buffer at buf
939	*
940	* fdt_get_path() computes the full path of the node at offset
941	* nodeoffset, and records that path in the buffer at buf.
942	*
943	* NOTE: This function is expensive, as it must scan the device tree
944	* structure from the start to nodeoffset.
945	*
946	* returns:
947	* 0, on success
948	* buf contains the absolute path of the node at
949	* nodeoffset, as a NUL-terminated string.
950	* -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
951	* -FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
952	* characters and will not fit in the given buffer.
953	* -FDT_ERR_BADMAGIC,
954	* -FDT_ERR_BADVERSION,
955	* -FDT_ERR_BADSTATE,
956	* -FDT_ERR_BADSTRUCTURE, standard meanings
957	*/
958	int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);
959
960	/**
961	* fdt_supernode_atdepth_offset - find a specific ancestor of a node
962	* @fdt: pointer to the device tree blob
963	* @nodeoffset: offset of the node whose parent to find
964	* @supernodedepth: depth of the ancestor to find
965	* @nodedepth: pointer to an integer variable (will be overwritten) or NULL
966	*
967	* fdt_supernode_atdepth_offset() finds an ancestor of the given node
968	* at a specific depth from the root (where the root itself has depth
969	* 0, its immediate subnodes depth 1 and so forth). So
970	* fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
971	* will always return 0, the offset of the root node. If the node at
972	* nodeoffset has depth D, then:
973	* fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
974	* will return nodeoffset itself.
975	*
976	* NOTE: This function is expensive, as it must scan the device tree
977	* structure from the start to nodeoffset.
978	*
979	* returns:
980	* structure block offset of the node at node offset's ancestor
981	* of depth supernodedepth (>=0), on success
982	* -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
983	* -FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of
984	* nodeoffset
985	* -FDT_ERR_BADMAGIC,
986	* -FDT_ERR_BADVERSION,
987	* -FDT_ERR_BADSTATE,
988	* -FDT_ERR_BADSTRUCTURE, standard meanings
989	*/
990	int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
991	int supernodedepth, int *nodedepth);
992
993	/**
994	* fdt_node_depth - find the depth of a given node
995	* @fdt: pointer to the device tree blob
996	* @nodeoffset: offset of the node whose parent to find
997	*
998	* fdt_node_depth() finds the depth of a given node. The root node
999	* has depth 0, its immediate subnodes depth 1 and so forth.
1000	*
1001	* NOTE: This function is expensive, as it must scan the device tree
1002	* structure from the start to nodeoffset.
1003	*
1004	* returns:
1005	* depth of the node at nodeoffset (>=0), on success
1006	* -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1007	* -FDT_ERR_BADMAGIC,
1008	* -FDT_ERR_BADVERSION,
1009	* -FDT_ERR_BADSTATE,
1010	* -FDT_ERR_BADSTRUCTURE, standard meanings
1011	*/
1012	int fdt_node_depth(const void *fdt, int nodeoffset);
1013
1014	/**
1015	* fdt_parent_offset - find the parent of a given node
1016	* @fdt: pointer to the device tree blob
1017	* @nodeoffset: offset of the node whose parent to find
1018	*
1019	* fdt_parent_offset() locates the parent node of a given node (that
1020	* is, it finds the offset of the node which contains the node at
1021	* nodeoffset as a subnode).
1022	*
1023	* NOTE: This function is expensive, as it must scan the device tree
1024	* structure from the start to nodeoffset, *twice*.
1025	*
1026	* returns:
1027	* structure block offset of the parent of the node at nodeoffset
1028	* (>=0), on success
1029	* -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1030	* -FDT_ERR_BADMAGIC,
1031	* -FDT_ERR_BADVERSION,
1032	* -FDT_ERR_BADSTATE,
1033	* -FDT_ERR_BADSTRUCTURE, standard meanings
1034	*/
1035	int fdt_parent_offset(const void *fdt, int nodeoffset);
1036
1037	/**
1038	* fdt_node_offset_by_prop_value - find nodes with a given property value
1039	* @fdt: pointer to the device tree blob
1040	* @startoffset: only find nodes after this offset
1041	* @propname: property name to check
1042	* @propval: property value to search for
1043	* @proplen: length of the value in propval
1044	*
1045	* fdt_node_offset_by_prop_value() returns the offset of the first
1046	* node after startoffset, which has a property named propname whose
1047	* value is of length proplen and has value equal to propval; or if
1048	* startoffset is -1, the very first such node in the tree.
1049	*
1050	* To iterate through all nodes matching the criterion, the following
1051	* idiom can be used:
1052	* offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
1053	* propval, proplen);
1054	* while (offset != -FDT_ERR_NOTFOUND) {
1055	* // other code here
1056	* offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
1057	* propval, proplen);
1058	* }
1059	*
1060	* Note the -1 in the first call to the function, if 0 is used here
1061	* instead, the function will never locate the root node, even if it
1062	* matches the criterion.
1063	*
1064	* returns:
1065	* structure block offset of the located node (>= 0, >startoffset),
1066	* on success
1067	* -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
1068	* tree after startoffset
1069	* -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1070	* -FDT_ERR_BADMAGIC,
1071	* -FDT_ERR_BADVERSION,
1072	* -FDT_ERR_BADSTATE,
1073	* -FDT_ERR_BADSTRUCTURE, standard meanings
1074	*/
1075	int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
1076	const char *propname,
1077	const void *propval, int proplen);
1078
1079	/**
1080	* fdt_node_offset_by_phandle - find the node with a given phandle
1081	* @fdt: pointer to the device tree blob
1082	* @phandle: phandle value
1083	*
1084	* fdt_node_offset_by_phandle() returns the offset of the node
1085	* which has the given phandle value. If there is more than one node
1086	* in the tree with the given phandle (an invalid tree), results are
1087	* undefined.
1088	*
1089	* returns:
1090	* structure block offset of the located node (>= 0), on success
1091	* -FDT_ERR_NOTFOUND, no node with that phandle exists
1092	* -FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
1093	* -FDT_ERR_BADMAGIC,
1094	* -FDT_ERR_BADVERSION,
1095	* -FDT_ERR_BADSTATE,
1096	* -FDT_ERR_BADSTRUCTURE, standard meanings
1097	*/
1098	int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);
1099
1100	/**
1101	* fdt_node_check_compatible - check a node's compatible property
1102	* @fdt: pointer to the device tree blob
1103	* @nodeoffset: offset of a tree node
1104	* @compatible: string to match against
1105	*
1106	* fdt_node_check_compatible() returns 0 if the given node contains a
1107	* @compatible property with the given string as one of its elements,
1108	* it returns non-zero otherwise, or on error.
1109	*
1110	* returns:
1111	* 0, if the node has a 'compatible' property listing the given string
1112	* 1, if the node has a 'compatible' property, but it does not list
1113	* the given string
1114	* -FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
1115	* -FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
1116	* -FDT_ERR_BADMAGIC,
1117	* -FDT_ERR_BADVERSION,
1118	* -FDT_ERR_BADSTATE,
1119	* -FDT_ERR_BADSTRUCTURE, standard meanings
1120	*/
1121	int fdt_node_check_compatible(const void *fdt, int nodeoffset,
1122	const char *compatible);
1123
1124	/**
1125	* fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
1126	* @fdt: pointer to the device tree blob
1127	* @startoffset: only find nodes after this offset
1128	* @compatible: 'compatible' string to match against
1129	*
1130	* fdt_node_offset_by_compatible() returns the offset of the first
1131	* node after startoffset, which has a 'compatible' property which
1132	* lists the given compatible string; or if startoffset is -1, the
1133	* very first such node in the tree.
1134	*
1135	* To iterate through all nodes matching the criterion, the following
1136	* idiom can be used:
1137	* offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
1138	* while (offset != -FDT_ERR_NOTFOUND) {
1139	* // other code here
1140	* offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
1141	* }
1142	*
1143	* Note the -1 in the first call to the function, if 0 is used here
1144	* instead, the function will never locate the root node, even if it
1145	* matches the criterion.
1146	*
1147	* returns:
1148	* structure block offset of the located node (>= 0, >startoffset),
1149	* on success
1150	* -FDT_ERR_NOTFOUND, no node matching the criterion exists in the
1151	* tree after startoffset
1152	* -FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
1153	* -FDT_ERR_BADMAGIC,
1154	* -FDT_ERR_BADVERSION,
1155	* -FDT_ERR_BADSTATE,
1156	* -FDT_ERR_BADSTRUCTURE, standard meanings
1157	*/
1158	int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
1159	const char *compatible);
1160
1161	/**
1162	* fdt_stringlist_contains - check a string list property for a string
1163	* @strlist: Property containing a list of strings to check
1164	* @listlen: Length of property
1165	* @str: String to search for
1166	*
1167	* This is a utility function provided for convenience. The list contains
1168	* one or more strings, each terminated by \0, as is found in a device tree
1169	* "compatible" property.
1170	*
1171	* Return: 1 if the string is found in the list, 0 not found, or invalid list
1172	*/
1173	int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
1174
1175	/**
1176	* fdt_stringlist_count - count the number of strings in a string list
1177	* @fdt: pointer to the device tree blob
1178	* @nodeoffset: offset of a tree node
1179	* @property: name of the property containing the string list
1180	*
1181	* Return:
1182	* the number of strings in the given property
1183	* -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1184	* -FDT_ERR_NOTFOUND if the property does not exist
1185	*/
1186	int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property);
1187
1188	/**
1189	* fdt_stringlist_search - find a string in a string list and return its index
1190	* @fdt: pointer to the device tree blob
1191	* @nodeoffset: offset of a tree node
1192	* @property: name of the property containing the string list
1193	* @string: string to look up in the string list
1194	*
1195	* Note that it is possible for this function to succeed on property values
1196	* that are not NUL-terminated. That's because the function will stop after
1197	* finding the first occurrence of @string. This can for example happen with
1198	* small-valued cell properties, such as #address-cells, when searching for
1199	* the empty string.
1200	*
1201	* return:
1202	* the index of the string in the list of strings
1203	* -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1204	* -FDT_ERR_NOTFOUND if the property does not exist or does not contain
1205	* the given string
1206	*/
1207	int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
1208	const char *string);
1209
1210	/**
1211	* fdt_stringlist_get() - obtain the string at a given index in a string list
1212	* @fdt: pointer to the device tree blob
1213	* @nodeoffset: offset of a tree node
1214	* @property: name of the property containing the string list
1215	* @index: index of the string to return
1216	* @lenp: return location for the string length or an error code on failure
1217	*
1218	* Note that this will successfully extract strings from properties with
1219	* non-NUL-terminated values. For example on small-valued cell properties
1220	* this function will return the empty string.
1221	*
1222	* If non-NULL, the length of the string (on success) or a negative error-code
1223	* (on failure) will be stored in the integer pointer to by lenp.
1224	*
1225	* Return:
1226	* A pointer to the string at the given index in the string list or NULL on
1227	* failure. On success the length of the string will be stored in the memory
1228	* location pointed to by the lenp parameter, if non-NULL. On failure one of
1229	* the following negative error codes will be returned in the lenp parameter
1230	* (if non-NULL):
1231	* -FDT_ERR_BADVALUE if the property value is not NUL-terminated
1232	* -FDT_ERR_NOTFOUND if the property does not exist
1233	*/
1234	const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
1235	const char *property, int index,
1236	int *lenp);
1237
1238	/**********************************************************************/
1239	/* Read-only functions (addressing related) */
1240	/**********************************************************************/
1241
1242	/**
1243	* FDT_MAX_NCELLS - maximum value for #address-cells and #size-cells
1244	*
1245	* This is the maximum value for #address-cells, #size-cells and
1246	* similar properties that will be processed by libfdt. IEE1275
1247	* requires that OF implementations handle values up to 4.
1248	* Implementations may support larger values, but in practice higher
1249	* values aren't used.
1250	*/
1251	#define FDT_MAX_NCELLS 4
1252
1253	/**
1254	* fdt_address_cells - retrieve address size for a bus represented in the tree
1255	* @fdt: pointer to the device tree blob
1256	* @nodeoffset: offset of the node to find the address size for
1257	*
1258	* When the node has a valid #address-cells property, returns its value.
1259	*
1260	* returns:
1261	* 0 <= n < FDT_MAX_NCELLS, on success
1262	* 2, if the node has no #address-cells property
1263	* -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1264	* #address-cells property
1265	* -FDT_ERR_BADMAGIC,
1266	* -FDT_ERR_BADVERSION,
1267	* -FDT_ERR_BADSTATE,
1268	* -FDT_ERR_BADSTRUCTURE,
1269	* -FDT_ERR_TRUNCATED, standard meanings
1270	*/
1271	int fdt_address_cells(const void *fdt, int nodeoffset);
1272
1273	/**
1274	* fdt_size_cells - retrieve address range size for a bus represented in the
1275	* tree
1276	* @fdt: pointer to the device tree blob
1277	* @nodeoffset: offset of the node to find the address range size for
1278	*
1279	* When the node has a valid #size-cells property, returns its value.
1280	*
1281	* returns:
1282	* 0 <= n < FDT_MAX_NCELLS, on success
1283	* 1, if the node has no #size-cells property
1284	* -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
1285	* #size-cells property
1286	* -FDT_ERR_BADMAGIC,
1287	* -FDT_ERR_BADVERSION,
1288	* -FDT_ERR_BADSTATE,
1289	* -FDT_ERR_BADSTRUCTURE,
1290	* -FDT_ERR_TRUNCATED, standard meanings
1291	*/
1292	int fdt_size_cells(const void *fdt, int nodeoffset);
1293
1294
1295	/**********************************************************************/
1296	/* Write-in-place functions */
1297	/**********************************************************************/
1298
1299	/**
1300	* fdt_setprop_inplace_namelen_partial - change a property's value,
1301	* but not its size
1302	* @fdt: pointer to the device tree blob
1303	* @nodeoffset: offset of the node whose property to change
1304	* @name: name of the property to change
1305	* @namelen: number of characters of name to consider
1306	* @idx: index of the property to change in the array
1307	* @val: pointer to data to replace the property value with
1308	* @len: length of the property value
1309	*
1310	* Identical to fdt_setprop_inplace(), but modifies the given property
1311	* starting from the given index, and using only the first characters
1312	* of the name. It is useful when you want to manipulate only one value of
1313	* an array and you have a string that doesn't end with \0.
1314	*
1315	* Return: 0 on success, negative libfdt error value otherwise
1316	*/
1317	#ifndef SWIG /* Not available in Python */
1318	int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
1319	const char *name, int namelen,
1320	uint32_t idx, const void *val,
1321	int len);
1322	#endif
1323
1324	/**
1325	* fdt_setprop_inplace - change a property's value, but not its size
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: pointer to data to replace the property value with
1330	* @len: length of the property value
1331	*
1332	* fdt_setprop_inplace() replaces the value of a given property with
1333	* the data in val, of length len. This function cannot change the
1334	* size of a property, and so will only work if len is equal to the
1335	* current length of the property.
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 len is not equal to the property's current length
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	*/
1352	#ifndef SWIG /* Not available in Python */
1353	int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
1354	const void *val, int len);
1355	#endif
1356
1357	/**
1358	* fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
1359	* @fdt: pointer to the device tree blob
1360	* @nodeoffset: offset of the node whose property to change
1361	* @name: name of the property to change
1362	* @val: 32-bit integer value to replace the property with
1363	*
1364	* fdt_setprop_inplace_u32() replaces the value of a given property
1365	* with the 32-bit integer value in val, converting val to big-endian
1366	* if necessary. This function cannot change the size of a property,
1367	* and so will only work if the property already exists and has length
1368	* 4.
1369	*
1370	* This function will alter only the bytes in the blob which contain
1371	* the given property value, and will not alter or move any other part
1372	* of the tree.
1373	*
1374	* returns:
1375	* 0, on success
1376	* -FDT_ERR_NOSPACE, if the property's length is not equal to 4
1377	* -FDT_ERR_NOTFOUND, node does not have the named property
1378	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1379	* -FDT_ERR_BADMAGIC,
1380	* -FDT_ERR_BADVERSION,
1381	* -FDT_ERR_BADSTATE,
1382	* -FDT_ERR_BADSTRUCTURE,
1383	* -FDT_ERR_TRUNCATED, standard meanings
1384	*/
1385	static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
1386	const char *name, uint32_t val)
1387	{
1388	fdt32_t tmp = cpu_to_fdt32(val);
1389	return fdt_setprop_inplace(fdt, nodeoffset, name, val: &tmp, len: sizeof(tmp));
1390	}
1391
1392	/**
1393	* fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
1394	* @fdt: pointer to the device tree blob
1395	* @nodeoffset: offset of the node whose property to change
1396	* @name: name of the property to change
1397	* @val: 64-bit integer value to replace the property with
1398	*
1399	* fdt_setprop_inplace_u64() replaces the value of a given property
1400	* with the 64-bit integer value in val, converting val to big-endian
1401	* if necessary. This function cannot change the size of a property,
1402	* and so will only work if the property already exists and has length
1403	* 8.
1404	*
1405	* This function will alter only the bytes in the blob which contain
1406	* the given property value, and will not alter or move any other part
1407	* of the tree.
1408	*
1409	* returns:
1410	* 0, on success
1411	* -FDT_ERR_NOSPACE, if the property's length is not equal to 8
1412	* -FDT_ERR_NOTFOUND, node does not have the named property
1413	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1414	* -FDT_ERR_BADMAGIC,
1415	* -FDT_ERR_BADVERSION,
1416	* -FDT_ERR_BADSTATE,
1417	* -FDT_ERR_BADSTRUCTURE,
1418	* -FDT_ERR_TRUNCATED, standard meanings
1419	*/
1420	static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
1421	const char *name, uint64_t val)
1422	{
1423	fdt64_t tmp = cpu_to_fdt64(val);
1424	return fdt_setprop_inplace(fdt, nodeoffset, name, val: &tmp, len: sizeof(tmp));
1425	}
1426
1427	/**
1428	* fdt_setprop_inplace_cell - change the value of a single-cell property
1429	* @fdt: pointer to the device tree blob
1430	* @nodeoffset: offset of the node containing the property
1431	* @name: name of the property to change the value of
1432	* @val: new value of the 32-bit cell
1433	*
1434	* This is an alternative name for fdt_setprop_inplace_u32()
1435	* Return: 0 on success, negative libfdt error number otherwise.
1436	*/
1437	static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
1438	const char *name, uint32_t val)
1439	{
1440	return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
1441	}
1442
1443	/**
1444	* fdt_nop_property - replace a property with nop tags
1445	* @fdt: pointer to the device tree blob
1446	* @nodeoffset: offset of the node whose property to nop
1447	* @name: name of the property to nop
1448	*
1449	* fdt_nop_property() will replace a given property's representation
1450	* in the blob with FDT_NOP tags, effectively removing it from the
1451	* tree.
1452	*
1453	* This function will alter only the bytes in the blob which contain
1454	* the property, and will not alter or move any other part of the
1455	* tree.
1456	*
1457	* returns:
1458	* 0, on success
1459	* -FDT_ERR_NOTFOUND, node does not have the named property
1460	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1461	* -FDT_ERR_BADMAGIC,
1462	* -FDT_ERR_BADVERSION,
1463	* -FDT_ERR_BADSTATE,
1464	* -FDT_ERR_BADSTRUCTURE,
1465	* -FDT_ERR_TRUNCATED, standard meanings
1466	*/
1467	int fdt_nop_property(void *fdt, int nodeoffset, const char *name);
1468
1469	/**
1470	* fdt_nop_node - replace a node (subtree) with nop tags
1471	* @fdt: pointer to the device tree blob
1472	* @nodeoffset: offset of the node to nop
1473	*
1474	* fdt_nop_node() will replace a given node's representation in the
1475	* blob, including all its subnodes, if any, with FDT_NOP tags,
1476	* effectively removing it from the tree.
1477	*
1478	* This function will alter only the bytes in the blob which contain
1479	* the node and its properties and subnodes, and will not alter or
1480	* move any other part of the tree.
1481	*
1482	* returns:
1483	* 0, on success
1484	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1485	* -FDT_ERR_BADMAGIC,
1486	* -FDT_ERR_BADVERSION,
1487	* -FDT_ERR_BADSTATE,
1488	* -FDT_ERR_BADSTRUCTURE,
1489	* -FDT_ERR_TRUNCATED, standard meanings
1490	*/
1491	int fdt_nop_node(void *fdt, int nodeoffset);
1492
1493	/**********************************************************************/
1494	/* Sequential write functions */
1495	/**********************************************************************/
1496
1497	/* fdt_create_with_flags flags */
1498	#define FDT_CREATE_FLAG_NO_NAME_DEDUP 0x1
1499	/* FDT_CREATE_FLAG_NO_NAME_DEDUP: Do not try to de-duplicate property
1500	* names in the fdt. This can result in faster creation times, but
1501	* a larger fdt. */
1502
1503	#define FDT_CREATE_FLAGS_ALL (FDT_CREATE_FLAG_NO_NAME_DEDUP)
1504
1505	/**
1506	* fdt_create_with_flags - begin creation of a new fdt
1507	* @buf: pointer to memory allocated where fdt will be created
1508	* @bufsize: size of the memory space at fdt
1509	* @flags: a valid combination of FDT_CREATE_FLAG_ flags, or 0.
1510	*
1511	* fdt_create_with_flags() begins the process of creating a new fdt with
1512	* the sequential write interface.
1513	*
1514	* fdt creation process must end with fdt_finish() to produce a valid fdt.
1515	*
1516	* returns:
1517	* 0, on success
1518	* -FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1519	* -FDT_ERR_BADFLAGS, flags is not valid
1520	*/
1521	int fdt_create_with_flags(void *buf, int bufsize, uint32_t flags);
1522
1523	/**
1524	* fdt_create - begin creation of a new fdt
1525	* @buf: pointer to memory allocated where fdt will be created
1526	* @bufsize: size of the memory space at fdt
1527	*
1528	* fdt_create() is equivalent to fdt_create_with_flags() with flags=0.
1529	*
1530	* returns:
1531	* 0, on success
1532	* -FDT_ERR_NOSPACE, bufsize is insufficient for a minimal fdt
1533	*/
1534	int fdt_create(void *buf, int bufsize);
1535
1536	int fdt_resize(void *fdt, void *buf, int bufsize);
1537	int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
1538	int fdt_finish_reservemap(void *fdt);
1539	int fdt_begin_node(void *fdt, const char *name);
1540	int fdt_property(void *fdt, const char *name, const void *val, int len);
1541	static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
1542	{
1543	fdt32_t tmp = cpu_to_fdt32(val);
1544	return fdt_property(fdt, name, val: &tmp, len: sizeof(tmp));
1545	}
1546	static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
1547	{
1548	fdt64_t tmp = cpu_to_fdt64(val);
1549	return fdt_property(fdt, name, val: &tmp, len: sizeof(tmp));
1550	}
1551
1552	#ifndef SWIG /* Not available in Python */
1553	static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
1554	{
1555	return fdt_property_u32(fdt, name, val);
1556	}
1557	#endif
1558
1559	/**
1560	* fdt_property_placeholder - add a new property and return a ptr to its value
1561	*
1562	* @fdt: pointer to the device tree blob
1563	* @name: name of property to add
1564	* @len: length of property value in bytes
1565	* @valp: returns a pointer to where where the value should be placed
1566	*
1567	* returns:
1568	* 0, on success
1569	* -FDT_ERR_BADMAGIC,
1570	* -FDT_ERR_NOSPACE, standard meanings
1571	*/
1572	int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp);
1573
1574	#define fdt_property_string(fdt, name, str) \
1575	fdt_property(fdt, name, str, strlen(str)+1)
1576	int fdt_end_node(void *fdt);
1577	int fdt_finish(void *fdt);
1578
1579	/**********************************************************************/
1580	/* Read-write functions */
1581	/**********************************************************************/
1582
1583	int fdt_create_empty_tree(void *buf, int bufsize);
1584	int fdt_open_into(const void *fdt, void *buf, int bufsize);
1585	int fdt_pack(void *fdt);
1586
1587	/**
1588	* fdt_add_mem_rsv - add one memory reserve map entry
1589	* @fdt: pointer to the device tree blob
1590	* @address: 64-bit start address of the reserve map entry
1591	* @size: 64-bit size of the reserved region
1592	*
1593	* Adds a reserve map entry to the given blob reserving a region at
1594	* address address of length size.
1595	*
1596	* This function will insert data into the reserve map and will
1597	* therefore change the indexes of some entries in the table.
1598	*
1599	* returns:
1600	* 0, on success
1601	* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1602	* contain the new reservation entry
1603	* -FDT_ERR_BADMAGIC,
1604	* -FDT_ERR_BADVERSION,
1605	* -FDT_ERR_BADSTATE,
1606	* -FDT_ERR_BADSTRUCTURE,
1607	* -FDT_ERR_BADLAYOUT,
1608	* -FDT_ERR_TRUNCATED, standard meanings
1609	*/
1610	int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);
1611
1612	/**
1613	* fdt_del_mem_rsv - remove a memory reserve map entry
1614	* @fdt: pointer to the device tree blob
1615	* @n: entry to remove
1616	*
1617	* fdt_del_mem_rsv() removes the n-th memory reserve map entry from
1618	* the blob.
1619	*
1620	* This function will delete data from the reservation table and will
1621	* therefore change the indexes of some entries in the table.
1622	*
1623	* returns:
1624	* 0, on success
1625	* -FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
1626	* are less than n+1 reserve map entries)
1627	* -FDT_ERR_BADMAGIC,
1628	* -FDT_ERR_BADVERSION,
1629	* -FDT_ERR_BADSTATE,
1630	* -FDT_ERR_BADSTRUCTURE,
1631	* -FDT_ERR_BADLAYOUT,
1632	* -FDT_ERR_TRUNCATED, standard meanings
1633	*/
1634	int fdt_del_mem_rsv(void *fdt, int n);
1635
1636	/**
1637	* fdt_set_name - change the name of a given node
1638	* @fdt: pointer to the device tree blob
1639	* @nodeoffset: structure block offset of a node
1640	* @name: name to give the node
1641	*
1642	* fdt_set_name() replaces the name (including unit address, if any)
1643	* of the given node with the given string. NOTE: this function can't
1644	* efficiently check if the new name is unique amongst the given
1645	* node's siblings; results are undefined if this function is invoked
1646	* with a name equal to one of the given node's siblings.
1647	*
1648	* This function may insert or delete data from the blob, and will
1649	* therefore change the offsets of some existing nodes.
1650	*
1651	* returns:
1652	* 0, on success
1653	* -FDT_ERR_NOSPACE, there is insufficient free space in the blob
1654	* to contain the new name
1655	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1656	* -FDT_ERR_BADMAGIC,
1657	* -FDT_ERR_BADVERSION,
1658	* -FDT_ERR_BADSTATE, standard meanings
1659	*/
1660	int fdt_set_name(void *fdt, int nodeoffset, const char *name);
1661
1662	/**
1663	* fdt_setprop - create or change a property
1664	* @fdt: pointer to the device tree blob
1665	* @nodeoffset: offset of the node whose property to change
1666	* @name: name of the property to change
1667	* @val: pointer to data to set the property value to
1668	* @len: length of the property value
1669	*
1670	* fdt_setprop() sets the value of the named property in the given
1671	* node to the given value and length, creating the property if it
1672	* does not already exist.
1673	*
1674	* This function may insert or delete data from the blob, and will
1675	* therefore change the offsets of some existing nodes.
1676	*
1677	* returns:
1678	* 0, on success
1679	* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1680	* contain the new property value
1681	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1682	* -FDT_ERR_BADLAYOUT,
1683	* -FDT_ERR_BADMAGIC,
1684	* -FDT_ERR_BADVERSION,
1685	* -FDT_ERR_BADSTATE,
1686	* -FDT_ERR_BADSTRUCTURE,
1687	* -FDT_ERR_BADLAYOUT,
1688	* -FDT_ERR_TRUNCATED, standard meanings
1689	*/
1690	int fdt_setprop(void *fdt, int nodeoffset, const char *name,
1691	const void *val, int len);
1692
1693	/**
1694	* fdt_setprop_placeholder - allocate space for a property
1695	* @fdt: pointer to the device tree blob
1696	* @nodeoffset: offset of the node whose property to change
1697	* @name: name of the property to change
1698	* @len: length of the property value
1699	* @prop_data: return pointer to property data
1700	*
1701	* fdt_setprop_placeholer() allocates the named property in the given node.
1702	* If the property exists it is resized. In either case a pointer to the
1703	* property data is returned.
1704	*
1705	* This function may insert or delete data from the blob, and will
1706	* therefore change the offsets of some existing nodes.
1707	*
1708	* returns:
1709	* 0, on success
1710	* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1711	* contain the new property value
1712	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1713	* -FDT_ERR_BADLAYOUT,
1714	* -FDT_ERR_BADMAGIC,
1715	* -FDT_ERR_BADVERSION,
1716	* -FDT_ERR_BADSTATE,
1717	* -FDT_ERR_BADSTRUCTURE,
1718	* -FDT_ERR_BADLAYOUT,
1719	* -FDT_ERR_TRUNCATED, standard meanings
1720	*/
1721	int fdt_setprop_placeholder(void *fdt, int nodeoffset, const char *name,
1722	int len, void **prop_data);
1723
1724	/**
1725	* fdt_setprop_u32 - set a property to a 32-bit integer
1726	* @fdt: pointer to the device tree blob
1727	* @nodeoffset: offset of the node whose property to change
1728	* @name: name of the property to change
1729	* @val: 32-bit integer value for the property (native endian)
1730	*
1731	* fdt_setprop_u32() sets the value of the named property in the given
1732	* node to the given 32-bit integer value (converting to big-endian if
1733	* necessary), or creates a new property with that value if it does
1734	* not already exist.
1735	*
1736	* This function may insert or delete data from the blob, and will
1737	* therefore change the offsets of some existing nodes.
1738	*
1739	* returns:
1740	* 0, on success
1741	* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1742	* contain the new property value
1743	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1744	* -FDT_ERR_BADLAYOUT,
1745	* -FDT_ERR_BADMAGIC,
1746	* -FDT_ERR_BADVERSION,
1747	* -FDT_ERR_BADSTATE,
1748	* -FDT_ERR_BADSTRUCTURE,
1749	* -FDT_ERR_BADLAYOUT,
1750	* -FDT_ERR_TRUNCATED, standard meanings
1751	*/
1752	static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
1753	uint32_t val)
1754	{
1755	fdt32_t tmp = cpu_to_fdt32(val);
1756	return fdt_setprop(fdt, nodeoffset, name, val: &tmp, len: sizeof(tmp));
1757	}
1758
1759	/**
1760	* fdt_setprop_u64 - set a property to a 64-bit integer
1761	* @fdt: pointer to the device tree blob
1762	* @nodeoffset: offset of the node whose property to change
1763	* @name: name of the property to change
1764	* @val: 64-bit integer value for the property (native endian)
1765	*
1766	* fdt_setprop_u64() sets the value of the named property in the given
1767	* node to the given 64-bit integer value (converting to big-endian if
1768	* necessary), or creates a new property with that value if it does
1769	* not already exist.
1770	*
1771	* This function may insert or delete data from the blob, and will
1772	* therefore change the offsets of some existing nodes.
1773	*
1774	* returns:
1775	* 0, on success
1776	* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1777	* contain the new property value
1778	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1779	* -FDT_ERR_BADLAYOUT,
1780	* -FDT_ERR_BADMAGIC,
1781	* -FDT_ERR_BADVERSION,
1782	* -FDT_ERR_BADSTATE,
1783	* -FDT_ERR_BADSTRUCTURE,
1784	* -FDT_ERR_BADLAYOUT,
1785	* -FDT_ERR_TRUNCATED, standard meanings
1786	*/
1787	static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
1788	uint64_t val)
1789	{
1790	fdt64_t tmp = cpu_to_fdt64(val);
1791	return fdt_setprop(fdt, nodeoffset, name, val: &tmp, len: sizeof(tmp));
1792	}
1793
1794	/**
1795	* fdt_setprop_cell - set a property to a single cell value
1796	* @fdt: pointer to the device tree blob
1797	* @nodeoffset: offset of the node whose property to change
1798	* @name: name of the property to change
1799	* @val: 32-bit integer value for the property (native endian)
1800	*
1801	* This is an alternative name for fdt_setprop_u32()
1802	*
1803	* Return: 0 on success, negative libfdt error value otherwise.
1804	*/
1805	static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
1806	uint32_t val)
1807	{
1808	return fdt_setprop_u32(fdt, nodeoffset, name, val);
1809	}
1810
1811	/**
1812	* fdt_setprop_string - set a property to a string value
1813	* @fdt: pointer to the device tree blob
1814	* @nodeoffset: offset of the node whose property to change
1815	* @name: name of the property to change
1816	* @str: string value for the property
1817	*
1818	* fdt_setprop_string() sets the value of the named property in the
1819	* given node to the given string value (using the length of the
1820	* string to determine the new length of the property), or creates a
1821	* new property with that value if it does not already exist.
1822	*
1823	* This function may insert or delete data from the blob, and will
1824	* therefore change the offsets of some existing nodes.
1825	*
1826	* returns:
1827	* 0, on success
1828	* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1829	* contain the new property value
1830	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1831	* -FDT_ERR_BADLAYOUT,
1832	* -FDT_ERR_BADMAGIC,
1833	* -FDT_ERR_BADVERSION,
1834	* -FDT_ERR_BADSTATE,
1835	* -FDT_ERR_BADSTRUCTURE,
1836	* -FDT_ERR_BADLAYOUT,
1837	* -FDT_ERR_TRUNCATED, standard meanings
1838	*/
1839	#define fdt_setprop_string(fdt, nodeoffset, name, str) \
1840	fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
1841
1842
1843	/**
1844	* fdt_setprop_empty - set a property to an empty value
1845	* @fdt: pointer to the device tree blob
1846	* @nodeoffset: offset of the node whose property to change
1847	* @name: name of the property to change
1848	*
1849	* fdt_setprop_empty() sets the value of the named property in the
1850	* given node to an empty (zero length) value, or creates a new empty
1851	* property if it does not already exist.
1852	*
1853	* This function may insert or delete data from the blob, and will
1854	* therefore change the offsets of some existing nodes.
1855	*
1856	* returns:
1857	* 0, on success
1858	* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1859	* contain the new property value
1860	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1861	* -FDT_ERR_BADLAYOUT,
1862	* -FDT_ERR_BADMAGIC,
1863	* -FDT_ERR_BADVERSION,
1864	* -FDT_ERR_BADSTATE,
1865	* -FDT_ERR_BADSTRUCTURE,
1866	* -FDT_ERR_BADLAYOUT,
1867	* -FDT_ERR_TRUNCATED, standard meanings
1868	*/
1869	#define fdt_setprop_empty(fdt, nodeoffset, name) \
1870	fdt_setprop((fdt), (nodeoffset), (name), NULL, 0)
1871
1872	/**
1873	* fdt_appendprop - append to or create 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 append to
1877	* @val: pointer to data to append to the property value
1878	* @len: length of the data to append to the property value
1879	*
1880	* fdt_appendprop() appends the value to the named property in the
1881	* given node, creating the property 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	int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
1900	const void *val, int len);
1901
1902	/**
1903	* fdt_appendprop_u32 - append a 32-bit integer value to a property
1904	* @fdt: pointer to the device tree blob
1905	* @nodeoffset: offset of the node whose property to change
1906	* @name: name of the property to change
1907	* @val: 32-bit integer value to append to the property (native endian)
1908	*
1909	* fdt_appendprop_u32() appends the given 32-bit integer value
1910	* (converting to big-endian if necessary) to the value of the named
1911	* property in the given node, or creates a new property with that
1912	* value if it does not already exist.
1913	*
1914	* This function may insert data into the blob, and will therefore
1915	* change the offsets of some existing nodes.
1916	*
1917	* returns:
1918	* 0, on success
1919	* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1920	* contain the new property value
1921	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1922	* -FDT_ERR_BADLAYOUT,
1923	* -FDT_ERR_BADMAGIC,
1924	* -FDT_ERR_BADVERSION,
1925	* -FDT_ERR_BADSTATE,
1926	* -FDT_ERR_BADSTRUCTURE,
1927	* -FDT_ERR_BADLAYOUT,
1928	* -FDT_ERR_TRUNCATED, standard meanings
1929	*/
1930	static inline int fdt_appendprop_u32(void *fdt, int nodeoffset,
1931	const char *name, uint32_t val)
1932	{
1933	fdt32_t tmp = cpu_to_fdt32(val);
1934	return fdt_appendprop(fdt, nodeoffset, name, val: &tmp, len: sizeof(tmp));
1935	}
1936
1937	/**
1938	* fdt_appendprop_u64 - append a 64-bit integer value to a property
1939	* @fdt: pointer to the device tree blob
1940	* @nodeoffset: offset of the node whose property to change
1941	* @name: name of the property to change
1942	* @val: 64-bit integer value to append to the property (native endian)
1943	*
1944	* fdt_appendprop_u64() appends the given 64-bit integer value
1945	* (converting to big-endian if necessary) to the value of the named
1946	* property in the given node, or creates a new property with that
1947	* value if it does not already exist.
1948	*
1949	* This function may insert data into the blob, and will therefore
1950	* change the offsets of some existing nodes.
1951	*
1952	* returns:
1953	* 0, on success
1954	* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
1955	* contain the new property value
1956	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
1957	* -FDT_ERR_BADLAYOUT,
1958	* -FDT_ERR_BADMAGIC,
1959	* -FDT_ERR_BADVERSION,
1960	* -FDT_ERR_BADSTATE,
1961	* -FDT_ERR_BADSTRUCTURE,
1962	* -FDT_ERR_BADLAYOUT,
1963	* -FDT_ERR_TRUNCATED, standard meanings
1964	*/
1965	static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
1966	const char *name, uint64_t val)
1967	{
1968	fdt64_t tmp = cpu_to_fdt64(val);
1969	return fdt_appendprop(fdt, nodeoffset, name, val: &tmp, len: sizeof(tmp));
1970	}
1971
1972	/**
1973	* fdt_appendprop_cell - append a single cell value to a property
1974	* @fdt: pointer to the device tree blob
1975	* @nodeoffset: offset of the node whose property to change
1976	* @name: name of the property to change
1977	* @val: 32-bit integer value to append to the property (native endian)
1978	*
1979	* This is an alternative name for fdt_appendprop_u32()
1980	*
1981	* Return: 0 on success, negative libfdt error value otherwise.
1982	*/
1983	static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
1984	const char *name, uint32_t val)
1985	{
1986	return fdt_appendprop_u32(fdt, nodeoffset, name, val);
1987	}
1988
1989	/**
1990	* fdt_appendprop_string - append a string to a property
1991	* @fdt: pointer to the device tree blob
1992	* @nodeoffset: offset of the node whose property to change
1993	* @name: name of the property to change
1994	* @str: string value to append to the property
1995	*
1996	* fdt_appendprop_string() appends the given string to the value of
1997	* the named property in the given node, or creates a new property
1998	* with that value if it does not already exist.
1999	*
2000	* This function may insert data into the blob, and will therefore
2001	* change the offsets of some existing nodes.
2002	*
2003	* returns:
2004	* 0, on success
2005	* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
2006	* contain the new property value
2007	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2008	* -FDT_ERR_BADLAYOUT,
2009	* -FDT_ERR_BADMAGIC,
2010	* -FDT_ERR_BADVERSION,
2011	* -FDT_ERR_BADSTATE,
2012	* -FDT_ERR_BADSTRUCTURE,
2013	* -FDT_ERR_BADLAYOUT,
2014	* -FDT_ERR_TRUNCATED, standard meanings
2015	*/
2016	#define fdt_appendprop_string(fdt, nodeoffset, name, str) \
2017	fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)
2018
2019	/**
2020	* fdt_appendprop_addrrange - append a address range property
2021	* @fdt: pointer to the device tree blob
2022	* @parent: offset of the parent node
2023	* @nodeoffset: offset of the node to add a property at
2024	* @name: name of property
2025	* @addr: start address of a given range
2026	* @size: size of a given range
2027	*
2028	* fdt_appendprop_addrrange() appends an address range value (start
2029	* address and size) to the value of the named property in the given
2030	* node, or creates a new property with that value if it does not
2031	* already exist.
2032	*
2033	* Cell sizes are determined by parent's #address-cells and #size-cells.
2034	*
2035	* This function may insert data into the blob, and will therefore
2036	* change the offsets of some existing nodes.
2037	*
2038	* returns:
2039	* 0, on success
2040	* -FDT_ERR_BADLAYOUT,
2041	* -FDT_ERR_BADMAGIC,
2042	* -FDT_ERR_BADNCELLS, if the node has a badly formatted or invalid
2043	* #address-cells property
2044	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2045	* -FDT_ERR_BADSTATE,
2046	* -FDT_ERR_BADSTRUCTURE,
2047	* -FDT_ERR_BADVERSION,
2048	* -FDT_ERR_BADVALUE, addr or size doesn't fit to respective cells size
2049	* -FDT_ERR_NOSPACE, there is insufficient free space in the blob to
2050	* contain a new property
2051	* -FDT_ERR_TRUNCATED, standard meanings
2052	*/
2053	int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
2054	const char *name, uint64_t addr, uint64_t size);
2055
2056	/**
2057	* fdt_delprop - delete a property
2058	* @fdt: pointer to the device tree blob
2059	* @nodeoffset: offset of the node whose property to nop
2060	* @name: name of the property to nop
2061	*
2062	* fdt_del_property() will delete the given property.
2063	*
2064	* This function will delete data from the blob, and will therefore
2065	* change the offsets of some existing nodes.
2066	*
2067	* returns:
2068	* 0, on success
2069	* -FDT_ERR_NOTFOUND, node does not have the named property
2070	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2071	* -FDT_ERR_BADLAYOUT,
2072	* -FDT_ERR_BADMAGIC,
2073	* -FDT_ERR_BADVERSION,
2074	* -FDT_ERR_BADSTATE,
2075	* -FDT_ERR_BADSTRUCTURE,
2076	* -FDT_ERR_TRUNCATED, standard meanings
2077	*/
2078	int fdt_delprop(void *fdt, int nodeoffset, const char *name);
2079
2080	/**
2081	* fdt_add_subnode_namelen - creates a new node based on substring
2082	* @fdt: pointer to the device tree blob
2083	* @parentoffset: structure block offset of a node
2084	* @name: name of the subnode to create
2085	* @namelen: number of characters of name to consider
2086	*
2087	* Identical to fdt_add_subnode(), but use only the first @namelen
2088	* characters of @name as the name of the new node. This is useful for
2089	* creating subnodes based on a portion of a larger string, such as a
2090	* full path.
2091	*
2092	* Return: structure block offset of the created subnode (>=0),
2093	* negative libfdt error value otherwise
2094	*/
2095	#ifndef SWIG /* Not available in Python */
2096	int fdt_add_subnode_namelen(void *fdt, int parentoffset,
2097	const char *name, int namelen);
2098	#endif
2099
2100	/**
2101	* fdt_add_subnode - creates a new node
2102	* @fdt: pointer to the device tree blob
2103	* @parentoffset: structure block offset of a node
2104	* @name: name of the subnode to locate
2105	*
2106	* fdt_add_subnode() creates a new node as a subnode of the node at
2107	* structure block offset parentoffset, with the given name (which
2108	* should include the unit address, if any).
2109	*
2110	* This function will insert data into the blob, and will therefore
2111	* change the offsets of some existing nodes.
2112	*
2113	* returns:
2114	* structure block offset of the created nodeequested subnode (>=0), on
2115	* success
2116	* -FDT_ERR_NOTFOUND, if the requested subnode does not exist
2117	* -FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE
2118	* tag
2119	* -FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
2120	* the given name
2121	* -FDT_ERR_NOSPACE, if there is insufficient free space in the
2122	* blob to contain the new node
2123	* -FDT_ERR_NOSPACE
2124	* -FDT_ERR_BADLAYOUT
2125	* -FDT_ERR_BADMAGIC,
2126	* -FDT_ERR_BADVERSION,
2127	* -FDT_ERR_BADSTATE,
2128	* -FDT_ERR_BADSTRUCTURE,
2129	* -FDT_ERR_TRUNCATED, standard meanings.
2130	*/
2131	int fdt_add_subnode(void *fdt, int parentoffset, const char *name);
2132
2133	/**
2134	* fdt_del_node - delete a node (subtree)
2135	* @fdt: pointer to the device tree blob
2136	* @nodeoffset: offset of the node to nop
2137	*
2138	* fdt_del_node() will remove the given node, including all its
2139	* subnodes if any, from the blob.
2140	*
2141	* This function will delete data from the blob, and will therefore
2142	* change the offsets of some existing nodes.
2143	*
2144	* returns:
2145	* 0, on success
2146	* -FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
2147	* -FDT_ERR_BADLAYOUT,
2148	* -FDT_ERR_BADMAGIC,
2149	* -FDT_ERR_BADVERSION,
2150	* -FDT_ERR_BADSTATE,
2151	* -FDT_ERR_BADSTRUCTURE,
2152	* -FDT_ERR_TRUNCATED, standard meanings
2153	*/
2154	int fdt_del_node(void *fdt, int nodeoffset);
2155
2156	/**
2157	* fdt_overlay_apply - Applies a DT overlay on a base DT
2158	* @fdt: pointer to the base device tree blob
2159	* @fdto: pointer to the device tree overlay blob
2160	*
2161	* fdt_overlay_apply() will apply the given device tree overlay on the
2162	* given base device tree.
2163	*
2164	* Expect the base device tree to be modified, even if the function
2165	* returns an error.
2166	*
2167	* returns:
2168	* 0, on success
2169	* -FDT_ERR_NOSPACE, there's not enough space in the base device tree
2170	* -FDT_ERR_NOTFOUND, the overlay points to some inexistant nodes or
2171	* properties in the base DT
2172	* -FDT_ERR_BADPHANDLE,
2173	* -FDT_ERR_BADOVERLAY,
2174	* -FDT_ERR_NOPHANDLES,
2175	* -FDT_ERR_INTERNAL,
2176	* -FDT_ERR_BADLAYOUT,
2177	* -FDT_ERR_BADMAGIC,
2178	* -FDT_ERR_BADOFFSET,
2179	* -FDT_ERR_BADPATH,
2180	* -FDT_ERR_BADVERSION,
2181	* -FDT_ERR_BADSTRUCTURE,
2182	* -FDT_ERR_BADSTATE,
2183	* -FDT_ERR_TRUNCATED, standard meanings
2184	*/
2185	int fdt_overlay_apply(void *fdt, void *fdto);
2186
2187	/**
2188	* fdt_overlay_target_offset - retrieves the offset of a fragment's target
2189	* @fdt: Base device tree blob
2190	* @fdto: Device tree overlay blob
2191	* @fragment_offset: node offset of the fragment in the overlay
2192	* @pathp: pointer which receives the path of the target (or NULL)
2193	*
2194	* fdt_overlay_target_offset() retrieves the target offset in the base
2195	* device tree of a fragment, no matter how the actual targeting is
2196	* done (through a phandle or a path)
2197	*
2198	* returns:
2199	* the targeted node offset in the base device tree
2200	* Negative error code on error
2201	*/
2202	int fdt_overlay_target_offset(const void *fdt, const void *fdto,
2203	int fragment_offset, char const **pathp);
2204
2205	/**********************************************************************/
2206	/* Debugging / informational functions */
2207	/**********************************************************************/
2208
2209	const char *fdt_strerror(int errval);
2210
2211	#ifdef __cplusplus
2212	}
2213	#endif
2214
2215	#endif /* LIBFDT_H */
2216