summaryrefslogtreecommitdiff
path: root/scripts/dtc/libfdt/libfdt.h
blob: 73f49759a5e71b79aa5bb4ae172681ce329cd294 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
#ifndef _LIBFDT_H
#define _LIBFDT_H
/*
 * libfdt - Flat Device Tree manipulation
 * Copyright (C) 2006 David Gibson, IBM Corporation.
 *
 * libfdt is dual licensed: you can use it either under the terms of
 * the GPL, or the BSD license, at your option.
 *
 *  a) This library is free software; you can redistribute it and/or
 *     modify it under the terms of the GNU General Public License as
 *     published by the Free Software Foundation; either version 2 of the
 *     License, or (at your option) any later version.
 *
 *     This library is distributed in the hope that it will be useful,
 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *     GNU General Public License for more details.
 *
 *     You should have received a copy of the GNU General Public
 *     License along with this library; if not, write to the Free
 *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
 *     MA 02110-1301 USA
 *
 * Alternatively,
 *
 *  b) Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *     1. Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *     2. Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <libfdt_env.h>
#include <fdt.h>

#define FDT_FIRST_SUPPORTED_VERSION	0x10
#define FDT_LAST_SUPPORTED_VERSION	0x11

/* Error codes: informative error codes */
#define FDT_ERR_NOTFOUND	1
	/* FDT_ERR_NOTFOUND: The requested node or property does not exist */
#define FDT_ERR_EXISTS		2
	/* FDT_ERR_EXISTS: Attemped to create a node or property which
	 * already exists */
#define FDT_ERR_NOSPACE		3
	/* FDT_ERR_NOSPACE: Operation needed to expand the device
	 * tree, but its buffer did not have sufficient space to
	 * contain the expanded tree. Use fdt_open_into() to move the
	 * device tree to a buffer with more space. */

/* Error codes: codes for bad parameters */
#define FDT_ERR_BADOFFSET	4
	/* FDT_ERR_BADOFFSET: Function was passed a structure block
	 * offset which is out-of-bounds, or which points to an
	 * unsuitable part of the structure for the operation. */
#define FDT_ERR_BADPATH		5
	/* FDT_ERR_BADPATH: Function was passed a badly formatted path
	 * (e.g. missing a leading / for a function which requires an
	 * absolute path) */
#define FDT_ERR_BADPHANDLE	6
	/* FDT_ERR_BADPHANDLE: Function was passed an invalid phandle
	 * value.  phandle values of 0 and -1 are not permitted. */
#define FDT_ERR_BADSTATE	7
	/* FDT_ERR_BADSTATE: Function was passed an incomplete device
	 * tree created by the sequential-write functions, which is
	 * not sufficiently complete for the requested operation. */

/* Error codes: codes for bad device tree blobs */
#define FDT_ERR_TRUNCATED	8
	/* FDT_ERR_TRUNCATED: Structure block of the given device tree
	 * ends without an FDT_END tag. */
#define FDT_ERR_BADMAGIC	9
	/* FDT_ERR_BADMAGIC: Given "device tree" appears not to be a
	 * device tree at all - it is missing the flattened device
	 * tree magic number. */
#define FDT_ERR_BADVERSION	10
	/* FDT_ERR_BADVERSION: Given device tree has a version which
	 * can't be handled by the requested operation.  For
	 * read-write functions, this may mean that fdt_open_into() is
	 * required to convert the tree to the expected version. */
#define FDT_ERR_BADSTRUCTURE	11
	/* FDT_ERR_BADSTRUCTURE: Given device tree has a corrupt
	 * structure block or other serious error (e.g. misnested
	 * nodes, or subnodes preceding properties). */
#define FDT_ERR_BADLAYOUT	12
	/* FDT_ERR_BADLAYOUT: For read-write functions, the given
	 * device tree has it's sub-blocks in an order that the
	 * function can't handle (memory reserve map, then structure,
	 * then strings).  Use fdt_open_into() to reorganize the tree
	 * into a form suitable for the read-write operations. */

/* "Can't happen" error indicating a bug in libfdt */
#define FDT_ERR_INTERNAL	13
	/* FDT_ERR_INTERNAL: libfdt has failed an internal assertion.
	 * Should never be returned, if it is, it indicates a bug in
	 * libfdt itself. */

#define FDT_ERR_MAX		13

/**********************************************************************/
/* Low-level functions (you probably don't need these)                */
/**********************************************************************/

const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int checklen);
static inline void *fdt_offset_ptr_w(void *fdt, int offset, int checklen)
{
	return (void *)(uintptr_t)fdt_offset_ptr(fdt, offset, checklen);
}

uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);

/**********************************************************************/
/* Traversal functions                                                */
/**********************************************************************/

int fdt_next_node(const void *fdt, int offset, int *depth);

/**********************************************************************/
/* General functions                                                  */
/**********************************************************************/

#define fdt_get_header(fdt, field) \
	(fdt32_to_cpu(((const struct fdt_header *)(fdt))->field))
#define fdt_magic(fdt) 			(fdt_get_header(fdt, magic))
#define fdt_totalsize(fdt)		(fdt_get_header(fdt, totalsize))
#define fdt_off_dt_struct(fdt)		(fdt_get_header(fdt, off_dt_struct))
#define fdt_off_dt_strings(fdt)		(fdt_get_header(fdt, off_dt_strings))
#define fdt_off_mem_rsvmap(fdt)		(fdt_get_header(fdt, off_mem_rsvmap))
#define fdt_version(fdt)		(fdt_get_header(fdt, version))
#define fdt_last_comp_version(fdt) 	(fdt_get_header(fdt, last_comp_version))
#define fdt_boot_cpuid_phys(fdt) 	(fdt_get_header(fdt, boot_cpuid_phys))
#define fdt_size_dt_strings(fdt) 	(fdt_get_header(fdt, size_dt_strings))
#define fdt_size_dt_struct(fdt)		(fdt_get_header(fdt, size_dt_struct))

#define __fdt_set_hdr(name) \
	static inline void fdt_set_##name(void *fdt, uint32_t val) \
	{ \
		struct fdt_header *fdth = (struct fdt_header*)fdt; \
		fdth->name = cpu_to_fdt32(val); \
	}
__fdt_set_hdr(magic);
__fdt_set_hdr(totalsize);
__fdt_set_hdr(off_dt_struct);
__fdt_set_hdr(off_dt_strings);
__fdt_set_hdr(off_mem_rsvmap);
__fdt_set_hdr(version);
__fdt_set_hdr(last_comp_version);
__fdt_set_hdr(boot_cpuid_phys);
__fdt_set_hdr(size_dt_strings);
__fdt_set_hdr(size_dt_struct);
#undef __fdt_set_hdr

/**
 * fdt_check_header - sanity check a device tree or possible device tree
 * @fdt: pointer to data which might be a flattened device tree
 *
 * fdt_check_header() checks that the given buffer contains what
 * appears to be a flattened device tree with sane information in its
 * header.
 *
 * returns:
 *     0, if the buffer appears to contain a valid device tree
 *     -FDT_ERR_BADMAGIC,
 *     -FDT_ERR_BADVERSION,
 *     -FDT_ERR_BADSTATE, standard meanings, as above
 */
int fdt_check_header(const void *fdt);

/**
 * fdt_move - move a device tree around in memory
 * @fdt: pointer to the device tree to move
 * @buf: pointer to memory where the device is to be moved
 * @bufsize: size of the memory space at buf
 *
 * fdt_move() relocates, if possible, the device tree blob located at
 * fdt to the buffer at buf of size bufsize.  The buffer may overlap
 * with the existing device tree blob at fdt.  Therefore,
 *     fdt_move(fdt, fdt, fdt_totalsize(fdt))
 * should always succeed.
 *
 * returns:
 *     0, on success
 *     -FDT_ERR_NOSPACE, bufsize is insufficient to contain the device tree
 *     -FDT_ERR_BADMAGIC,
 *     -FDT_ERR_BADVERSION,
 *     -FDT_ERR_BADSTATE, standard meanings
 */
int fdt_move(const void *fdt, void *buf, int bufsize);

/**********************************************************************/
/* Read-only functions                                                */
/**********************************************************************/

/**
 * fdt_string - retrieve a string from the strings block of a device tree
 * @fdt: pointer to the device tree blob
 * @stroffset: offset of the string within the strings block (native endian)
 *
 * fdt_string() retrieves a pointer to a single string from the
 * strings block of the device tree blob at fdt.
 *
 * returns:
 *     a pointer to the string, on success
 *     NULL, if stroffset is out of bounds
 */
const char *fdt_string(const void *fdt, int stroffset);

/**
 * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
 * @fdt: pointer to the device tree blob
 *
 * Returns the number of entries in the device tree blob's memory
 * reservation map.  This does not include the terminating 0,0 entry
 * or any other (0,0) entries reserved for expansion.
 *
 * returns:
 *     the number of entries
 */
int fdt_num_mem_rsv(const void *fdt);

/**
 * fdt_get_mem_rsv - retrieve one memory reserve map entry
 * @fdt: pointer to the device tree blob
 * @address, @size: pointers to 64-bit variables
 *
 * On success, *address and *size will contain the address and size of
 * the n-th reserve map entry from the device tree blob, in
 * native-endian format.
 *
 * returns:
 *     0, on success
 *     -FDT_ERR_BADMAGIC,
 *     -FDT_ERR_BADVERSION,
 *     -FDT_ERR_BADSTATE, standard meanings
 */
int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size);

/**
 * fdt_subnode_offset_namelen - find a subnode based on substring
 * @fdt: pointer to the device tree blob
 * @parentoffset: structure block offset of a node
 * @name: name of the subnode to locate
 * @namelen: number of characters of name to consider
 *
 * Identical to fdt_subnode_offset(), but only examine the first
 * namelen characters of name for matching the subnode name.  This is
 * useful for finding subnodes based on a portion of a larger string,
 * such as a full path.
 */
int fdt_subnode_offset_namelen(const void *fdt, int parentoffset,
			       const char *name, int namelen);
/**
 * fdt_subnode_offset - find a subnode of a given node
 * @fdt: pointer to the device tree blob
 * @parentoffset: structure block offset of a node
 * @name: name of the subnode to locate
 *
 * fdt_subnode_offset() finds a subnode of the node at structure block
 * offset parentoffset with the given name.  name may include a unit
 * address, in which case fdt_subnode_offset() will find the subnode
 * with that unit address, or the unit address may be omitted, in
 * which case fdt_subnode_offset() will find an arbitrary subnode
 * whose name excluding unit address matches the given name.
 *
 * returns:
 *	structure block offset of the requested subnode (>=0), on success
 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
 *      -FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_TRUNCATED, standard meanings.
 */
int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);

/**
 * fdt_path_offset - find a tree node by its full path
 * @fdt: pointer to the device tree blob
 * @path: full path of the node to locate
 *
 * fdt_path_offset() finds a node of a given path in the device tree.
 * Each path component may omit the unit address portion, but the
 * results of this are undefined if any such path component is
 * ambiguous (that is if there are multiple nodes at the relevant
 * level matching the given component, differentiated only by unit
 * address).
 *
 * returns:
 *	structure block offset of the node with the requested path (>=0), on success
 *	-FDT_ERR_BADPATH, given path does not begin with '/' or is invalid
 *	-FDT_ERR_NOTFOUND, if the requested node does not exist
 *      -FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_TRUNCATED, standard meanings.
 */
int fdt_path_offset(const void *fdt, const char *path);

/**
 * fdt_get_name - retrieve the name of a given node
 * @fdt: pointer to the device tree blob
 * @nodeoffset: structure block offset of the starting node
 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 *
 * fdt_get_name() retrieves the name (including unit address) of the
 * device tree node at structure block offset nodeoffset.  If lenp is
 * non-NULL, the length of this name is also returned, in the integer
 * pointed to by lenp.
 *
 * returns:
 *	pointer to the node's name, on success
 *		If lenp is non-NULL, *lenp contains the length of that name (>=0)
 *	NULL, on error
 *		if lenp is non-NULL *lenp contains an error code (<0):
 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *		-FDT_ERR_BADMAGIC,
 *		-FDT_ERR_BADVERSION,
 *		-FDT_ERR_BADSTATE, standard meanings
 */
const char *fdt_get_name(const void *fdt, int nodeoffset, int *lenp);

/**
 * fdt_first_property_offset - find the offset of a node's first property
 * @fdt: pointer to the device tree blob
 * @nodeoffset: structure block offset of a node
 *
 * fdt_first_property_offset() finds the first property of the node at
 * the given structure block offset.
 *
 * returns:
 *	structure block offset of the property (>=0), on success
 *	-FDT_ERR_NOTFOUND, if the requested node has no properties
 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_BEGIN_NODE tag
 *      -FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_TRUNCATED, standard meanings.
 */
int fdt_first_property_offset(const void *fdt, int nodeoffset);

/**
 * fdt_next_property_offset - step through a node's properties
 * @fdt: pointer to the device tree blob
 * @offset: structure block offset of a property
 *
 * fdt_next_property_offset() finds the property immediately after the
 * one at the given structure block offset.  This will be a property
 * of the same node as the given property.
 *
 * returns:
 *	structure block offset of the next property (>=0), on success
 *	-FDT_ERR_NOTFOUND, if the given property is the last in its node
 *	-FDT_ERR_BADOFFSET, if nodeoffset did not point to an FDT_PROP tag
 *      -FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_TRUNCATED, standard meanings.
 */
int fdt_next_property_offset(const void *fdt, int offset);

/**
 * fdt_get_property_by_offset - retrieve the property at a given offset
 * @fdt: pointer to the device tree blob
 * @offset: offset of the property to retrieve
 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 *
 * fdt_get_property_by_offset() retrieves a pointer to the
 * fdt_property structure within the device tree blob at the given
 * offset.  If lenp is non-NULL, the length of the property value is
 * also returned, in the integer pointed to by lenp.
 *
 * returns:
 *	pointer to the structure representing the property
 *		if lenp is non-NULL, *lenp contains the length of the property
 *		value (>=0)
 *	NULL, on error
 *		if lenp is non-NULL, *lenp contains an error code (<0):
 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
 *		-FDT_ERR_BADMAGIC,
 *		-FDT_ERR_BADVERSION,
 *		-FDT_ERR_BADSTATE,
 *		-FDT_ERR_BADSTRUCTURE,
 *		-FDT_ERR_TRUNCATED, standard meanings
 */
const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
						      int offset,
						      int *lenp);

/**
 * fdt_get_property_namelen - find a property based on substring
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to find
 * @name: name of the property to find
 * @namelen: number of characters of name to consider
 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 *
 * Identical to fdt_get_property_namelen(), but only examine the first
 * namelen characters of name for matching the property name.
 */
const struct fdt_property *fdt_get_property_namelen(const void *fdt,
						    int nodeoffset,
						    const char *name,
						    int namelen, int *lenp);

/**
 * fdt_get_property - find a given property in a given node
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to find
 * @name: name of the property to find
 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 *
 * fdt_get_property() retrieves a pointer to the fdt_property
 * structure within the device tree blob corresponding to the property
 * named 'name' of the node at offset nodeoffset.  If lenp is
 * non-NULL, the length of the property value is also returned, in the
 * integer pointed to by lenp.
 *
 * returns:
 *	pointer to the structure representing the property
 *		if lenp is non-NULL, *lenp contains the length of the property
 *		value (>=0)
 *	NULL, on error
 *		if lenp is non-NULL, *lenp contains an error code (<0):
 *		-FDT_ERR_NOTFOUND, node does not have named property
 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *		-FDT_ERR_BADMAGIC,
 *		-FDT_ERR_BADVERSION,
 *		-FDT_ERR_BADSTATE,
 *		-FDT_ERR_BADSTRUCTURE,
 *		-FDT_ERR_TRUNCATED, standard meanings
 */
const struct fdt_property *fdt_get_property(const void *fdt, int nodeoffset,
					    const char *name, int *lenp);
static inline struct fdt_property *fdt_get_property_w(void *fdt, int nodeoffset,
						      const char *name,
						      int *lenp)
{
	return (struct fdt_property *)(uintptr_t)
		fdt_get_property(fdt, nodeoffset, name, lenp);
}

/**
 * fdt_getprop_by_offset - retrieve the value of a property at a given offset
 * @fdt: pointer to the device tree blob
 * @ffset: offset of the property to read
 * @namep: pointer to a string variable (will be overwritten) or NULL
 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 *
 * fdt_getprop_by_offset() retrieves a pointer to the value of the
 * property at structure block offset 'offset' (this will be a pointer
 * to within the device blob itself, not a copy of the value).  If
 * lenp is non-NULL, the length of the property value is also
 * returned, in the integer pointed to by lenp.  If namep is non-NULL,
 * the property's namne will also be returned in the char * pointed to
 * by namep (this will be a pointer to within the device tree's string
 * block, not a new copy of the name).
 *
 * returns:
 *	pointer to the property's value
 *		if lenp is non-NULL, *lenp contains the length of the property
 *		value (>=0)
 *		if namep is non-NULL *namep contiains a pointer to the property
 *		name.
 *	NULL, on error
 *		if lenp is non-NULL, *lenp contains an error code (<0):
 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_PROP tag
 *		-FDT_ERR_BADMAGIC,
 *		-FDT_ERR_BADVERSION,
 *		-FDT_ERR_BADSTATE,
 *		-FDT_ERR_BADSTRUCTURE,
 *		-FDT_ERR_TRUNCATED, standard meanings
 */
const void *fdt_getprop_by_offset(const void *fdt, int offset,
				  const char **namep, int *lenp);

/**
 * fdt_getprop_namelen - get property value based on substring
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to find
 * @name: name of the property to find
 * @namelen: number of characters of name to consider
 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 *
 * Identical to fdt_getprop(), but only examine the first namelen
 * characters of name for matching the property name.
 */
const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
				const char *name, int namelen, int *lenp);

/**
 * fdt_getprop - retrieve the value of a given property
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to find
 * @name: name of the property to find
 * @lenp: pointer to an integer variable (will be overwritten) or NULL
 *
 * fdt_getprop() retrieves a pointer to the value of the property
 * named 'name' of the node at offset nodeoffset (this will be a
 * pointer to within the device blob itself, not a copy of the value).
 * If lenp is non-NULL, the length of the property value is also
 * returned, in the integer pointed to by lenp.
 *
 * returns:
 *	pointer to the property's value
 *		if lenp is non-NULL, *lenp contains the length of the property
 *		value (>=0)
 *	NULL, on error
 *		if lenp is non-NULL, *lenp contains an error code (<0):
 *		-FDT_ERR_NOTFOUND, node does not have named property
 *		-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *		-FDT_ERR_BADMAGIC,
 *		-FDT_ERR_BADVERSION,
 *		-FDT_ERR_BADSTATE,
 *		-FDT_ERR_BADSTRUCTURE,
 *		-FDT_ERR_TRUNCATED, standard meanings
 */
const void *fdt_getprop(const void *fdt, int nodeoffset,
			const char *name, int *lenp);
static inline void *fdt_getprop_w(void *fdt, int nodeoffset,
				  const char *name, int *lenp)
{
	return (void *)(uintptr_t)fdt_getprop(fdt, nodeoffset, name, lenp);
}

/**
 * fdt_get_phandle - retrieve the phandle of a given node
 * @fdt: pointer to the device tree blob
 * @nodeoffset: structure block offset of the node
 *
 * fdt_get_phandle() retrieves the phandle of the device tree node at
 * structure block offset nodeoffset.
 *
 * returns:
 *	the phandle of the node at nodeoffset, on success (!= 0, != -1)
 *	0, if the node has no phandle, or another error occurs
 */
uint32_t fdt_get_phandle(const void *fdt, int nodeoffset);

/**
 * fdt_get_alias_namelen - get alias based on substring
 * @fdt: pointer to the device tree blob
 * @name: name of the alias th look up
 * @namelen: number of characters of name to consider
 *
 * Identical to fdt_get_alias(), but only examine the first namelen
 * characters of name for matching the alias name.
 */
const char *fdt_get_alias_namelen(const void *fdt,
				  const char *name, int namelen);

/**
 * fdt_get_alias - retreive the path referenced by a given alias
 * @fdt: pointer to the device tree blob
 * @name: name of the alias th look up
 *
 * fdt_get_alias() retrieves the value of a given alias.  That is, the
 * value of the property named 'name' in the node /aliases.
 *
 * returns:
 *	a pointer to the expansion of the alias named 'name', of it exists
 *	NULL, if the given alias or the /aliases node does not exist
 */
const char *fdt_get_alias(const void *fdt, const char *name);

/**
 * fdt_get_path - determine the full path of a node
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose path to find
 * @buf: character buffer to contain the returned path (will be overwritten)
 * @buflen: size of the character buffer at buf
 *
 * fdt_get_path() computes the full path of the node at offset
 * nodeoffset, and records that path in the buffer at buf.
 *
 * NOTE: This function is expensive, as it must scan the device tree
 * structure from the start to nodeoffset.
 *
 * returns:
 *	0, on success
 *		buf contains the absolute path of the node at
 *		nodeoffset, as a NUL-terminated string.
 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 *	-FDT_ERR_NOSPACE, the path of the given node is longer than (bufsize-1)
 *		characters and will not fit in the given buffer.
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 */
int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen);

/**
 * fdt_supernode_atdepth_offset - find a specific ancestor of a node
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose parent to find
 * @supernodedepth: depth of the ancestor to find
 * @nodedepth: pointer to an integer variable (will be overwritten) or NULL
 *
 * fdt_supernode_atdepth_offset() finds an ancestor of the given node
 * at a specific depth from the root (where the root itself has depth
 * 0, its immediate subnodes depth 1 and so forth).  So
 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, NULL);
 * will always return 0, the offset of the root node.  If the node at
 * nodeoffset has depth D, then:
 *	fdt_supernode_atdepth_offset(fdt, nodeoffset, D, NULL);
 * will return nodeoffset itself.
 *
 * NOTE: This function is expensive, as it must scan the device tree
 * structure from the start to nodeoffset.
 *
 * returns:

 *	structure block offset of the node at node offset's ancestor
 *		of depth supernodedepth (>=0), on success
 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
*	-FDT_ERR_NOTFOUND, supernodedepth was greater than the depth of nodeoffset
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 */
int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
				 int supernodedepth, int *nodedepth);

/**
 * fdt_node_depth - find the depth of a given node
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose parent to find
 *
 * fdt_node_depth() finds the depth of a given node.  The root node
 * has depth 0, its immediate subnodes depth 1 and so forth.
 *
 * NOTE: This function is expensive, as it must scan the device tree
 * structure from the start to nodeoffset.
 *
 * returns:
 *	depth of the node at nodeoffset (>=0), on success
 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 */
int fdt_node_depth(const void *fdt, int nodeoffset);

/**
 * fdt_parent_offset - find the parent of a given node
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose parent to find
 *
 * fdt_parent_offset() locates the parent node of a given node (that
 * is, it finds the offset of the node which contains the node at
 * nodeoffset as a subnode).
 *
 * NOTE: This function is expensive, as it must scan the device tree
 * structure from the start to nodeoffset, *twice*.
 *
 * returns:
 *	structure block offset of the parent of the node at nodeoffset
 *		(>=0), on success
 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 */
int fdt_parent_offset(const void *fdt, int nodeoffset);

/**
 * fdt_node_offset_by_prop_value - find nodes with a given property value
 * @fdt: pointer to the device tree blob
 * @startoffset: only find nodes after this offset
 * @propname: property name to check
 * @propval: property value to search for
 * @proplen: length of the value in propval
 *
 * fdt_node_offset_by_prop_value() returns the offset of the first
 * node after startoffset, which has a property named propname whose
 * value is of length proplen and has value equal to propval; or if
 * startoffset is -1, the very first such node in the tree.
 *
 * To iterate through all nodes matching the criterion, the following
 * idiom can be used:
 *	offset = fdt_node_offset_by_prop_value(fdt, -1, propname,
 *					       propval, proplen);
 *	while (offset != -FDT_ERR_NOTFOUND) {
 *		// other code here
 *		offset = fdt_node_offset_by_prop_value(fdt, offset, propname,
 *						       propval, proplen);
 *	}
 *
 * Note the -1 in the first call to the function, if 0 is used here
 * instead, the function will never locate the root node, even if it
 * matches the criterion.
 *
 * returns:
 *	structure block offset of the located node (>= 0, >startoffset),
 *		 on success
 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
 *		tree after startoffset
 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 */
int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
				  const char *propname,
				  const void *propval, int proplen);

/**
 * fdt_node_offset_by_phandle - find the node with a given phandle
 * @fdt: pointer to the device tree blob
 * @phandle: phandle value
 *
 * fdt_node_offset_by_phandle() returns the offset of the node
 * which has the given phandle value.  If there is more than one node
 * in the tree with the given phandle (an invalid tree), results are
 * undefined.
 *
 * returns:
 *	structure block offset of the located node (>= 0), on success
 *	-FDT_ERR_NOTFOUND, no node with that phandle exists
 *	-FDT_ERR_BADPHANDLE, given phandle value was invalid (0 or -1)
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 */
int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle);

/**
 * fdt_node_check_compatible: check a node's compatible property
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of a tree node
 * @compatible: string to match against
 *
 *
 * fdt_node_check_compatible() returns 0 if the given node contains a
 * 'compatible' property with the given string as one of its elements,
 * it returns non-zero otherwise, or on error.
 *
 * returns:
 *	0, if the node has a 'compatible' property listing the given string
 *	1, if the node has a 'compatible' property, but it does not list
 *		the given string
 *	-FDT_ERR_NOTFOUND, if the given node has no 'compatible' property
 * 	-FDT_ERR_BADOFFSET, if nodeoffset does not refer to a BEGIN_NODE tag
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 */
int fdt_node_check_compatible(const void *fdt, int nodeoffset,
			      const char *compatible);

/**
 * fdt_node_offset_by_compatible - find nodes with a given 'compatible' value
 * @fdt: pointer to the device tree blob
 * @startoffset: only find nodes after this offset
 * @compatible: 'compatible' string to match against
 *
 * fdt_node_offset_by_compatible() returns the offset of the first
 * node after startoffset, which has a 'compatible' property which
 * lists the given compatible string; or if startoffset is -1, the
 * very first such node in the tree.
 *
 * To iterate through all nodes matching the criterion, the following
 * idiom can be used:
 *	offset = fdt_node_offset_by_compatible(fdt, -1, compatible);
 *	while (offset != -FDT_ERR_NOTFOUND) {
 *		// other code here
 *		offset = fdt_node_offset_by_compatible(fdt, offset, compatible);
 *	}
 *
 * Note the -1 in the first call to the function, if 0 is used here
 * instead, the function will never locate the root node, even if it
 * matches the criterion.
 *
 * returns:
 *	structure block offset of the located node (>= 0, >startoffset),
 *		 on success
 *	-FDT_ERR_NOTFOUND, no node matching the criterion exists in the
 *		tree after startoffset
 * 	-FDT_ERR_BADOFFSET, nodeoffset does not refer to a BEGIN_NODE tag
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE, standard meanings
 */
int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
				  const char *compatible);

/**********************************************************************/
/* Write-in-place functions                                           */
/**********************************************************************/

/**
 * fdt_setprop_inplace - change a property's value, but not its size
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to change
 * @name: name of the property to change
 * @val: pointer to data to replace the property value with
 * @len: length of the property value
 *
 * fdt_setprop_inplace() replaces the value of a given property with
 * the data in val, of length len.  This function cannot change the
 * size of a property, and so will only work if len is equal to the
 * current length of the property.
 *
 * This function will alter only the bytes in the blob which contain
 * the given property value, and will not alter or move any other part
 * of the tree.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOSPACE, if len is not equal to the property's current length
 *	-FDT_ERR_NOTFOUND, node does not have the named property
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
			const void *val, int len);

/**
 * fdt_setprop_inplace_u32 - change the value of a 32-bit integer property
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to change
 * @name: name of the property to change
 * @val: 32-bit integer value to replace the property with
 *
 * fdt_setprop_inplace_u32() replaces the value of a given property
 * with the 32-bit integer value in val, converting val to big-endian
 * if necessary.  This function cannot change the size of a property,
 * and so will only work if the property already exists and has length
 * 4.
 *
 * This function will alter only the bytes in the blob which contain
 * the given property value, and will not alter or move any other part
 * of the tree.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 4
 *	-FDT_ERR_NOTFOUND, node does not have the named property
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
static inline int fdt_setprop_inplace_u32(void *fdt, int nodeoffset,
					  const char *name, uint32_t val)
{
	val = cpu_to_fdt32(val);
	return fdt_setprop_inplace(fdt, nodeoffset, name, &val, sizeof(val));
}

/**
 * fdt_setprop_inplace_u64 - change the value of a 64-bit integer property
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to change
 * @name: name of the property to change
 * @val: 64-bit integer value to replace the property with
 *
 * fdt_setprop_inplace_u64() replaces the value of a given property
 * with the 64-bit integer value in val, converting val to big-endian
 * if necessary.  This function cannot change the size of a property,
 * and so will only work if the property already exists and has length
 * 8.
 *
 * This function will alter only the bytes in the blob which contain
 * the given property value, and will not alter or move any other part
 * of the tree.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOSPACE, if the property's length is not equal to 8
 *	-FDT_ERR_NOTFOUND, node does not have the named property
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
static inline int fdt_setprop_inplace_u64(void *fdt, int nodeoffset,
					  const char *name, uint64_t val)
{
	val = cpu_to_fdt64(val);
	return fdt_setprop_inplace(fdt, nodeoffset, name, &val, sizeof(val));
}

/**
 * fdt_setprop_inplace_cell - change the value of a single-cell property
 *
 * This is an alternative name for fdt_setprop_inplace_u32()
 */
static inline int fdt_setprop_inplace_cell(void *fdt, int nodeoffset,
					   const char *name, uint32_t val)
{
	return fdt_setprop_inplace_u32(fdt, nodeoffset, name, val);
}

/**
 * fdt_nop_property - replace a property with nop tags
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to nop
 * @name: name of the property to nop
 *
 * fdt_nop_property() will replace a given property's representation
 * in the blob with FDT_NOP tags, effectively removing it from the
 * tree.
 *
 * This function will alter only the bytes in the blob which contain
 * the property, and will not alter or move any other part of the
 * tree.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOTFOUND, node does not have the named property
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
int fdt_nop_property(void *fdt, int nodeoffset, const char *name);

/**
 * fdt_nop_node - replace a node (subtree) with nop tags
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node to nop
 *
 * fdt_nop_node() will replace a given node's representation in the
 * blob, including all its subnodes, if any, with FDT_NOP tags,
 * effectively removing it from the tree.
 *
 * This function will alter only the bytes in the blob which contain
 * the node and its properties and subnodes, and will not alter or
 * move any other part of the tree.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
int fdt_nop_node(void *fdt, int nodeoffset);

/**********************************************************************/
/* Sequential write functions                                         */
/**********************************************************************/

int fdt_create(void *buf, int bufsize);
int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size);
int fdt_finish_reservemap(void *fdt);
int fdt_begin_node(void *fdt, const char *name);
int fdt_property(void *fdt, const char *name, const void *val, int len);
static inline int fdt_property_u32(void *fdt, const char *name, uint32_t val)
{
	val = cpu_to_fdt32(val);
	return fdt_property(fdt, name, &val, sizeof(val));
}
static inline int fdt_property_u64(void *fdt, const char *name, uint64_t val)
{
	val = cpu_to_fdt64(val);
	return fdt_property(fdt, name, &val, sizeof(val));
}
static inline int fdt_property_cell(void *fdt, const char *name, uint32_t val)
{
	return fdt_property_u32(fdt, name, val);
}
#define fdt_property_string(fdt, name, str) \
	fdt_property(fdt, name, str, strlen(str)+1)
int fdt_end_node(void *fdt);
int fdt_finish(void *fdt);

/**********************************************************************/
/* Read-write functions                                               */
/**********************************************************************/

int fdt_create_empty_tree(void *buf, int bufsize);
int fdt_open_into(const void *fdt, void *buf, int bufsize);
int fdt_pack(void *fdt);

/**
 * fdt_add_mem_rsv - add one memory reserve map entry
 * @fdt: pointer to the device tree blob
 * @address, @size: 64-bit values (native endian)
 *
 * Adds a reserve map entry to the given blob reserving a region at
 * address address of length size.
 *
 * This function will insert data into the reserve map and will
 * therefore change the indexes of some entries in the table.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 *		contain the new reservation entry
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size);

/**
 * fdt_del_mem_rsv - remove a memory reserve map entry
 * @fdt: pointer to the device tree blob
 * @n: entry to remove
 *
 * fdt_del_mem_rsv() removes the n-th memory reserve map entry from
 * the blob.
 *
 * This function will delete data from the reservation table and will
 * therefore change the indexes of some entries in the table.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOTFOUND, there is no entry of the given index (i.e. there
 *		are less than n+1 reserve map entries)
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
int fdt_del_mem_rsv(void *fdt, int n);

/**
 * fdt_set_name - change the name of a given node
 * @fdt: pointer to the device tree blob
 * @nodeoffset: structure block offset of a node
 * @name: name to give the node
 *
 * fdt_set_name() replaces the name (including unit address, if any)
 * of the given node with the given string.  NOTE: this function can't
 * efficiently check if the new name is unique amongst the given
 * node's siblings; results are undefined if this function is invoked
 * with a name equal to one of the given node's siblings.
 *
 * This function may insert or delete data from the blob, and will
 * therefore change the offsets of some existing nodes.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob
 *		to contain the new name
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE, standard meanings
 */
int fdt_set_name(void *fdt, int nodeoffset, const char *name);

/**
 * fdt_setprop - create or change a property
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to change
 * @name: name of the property to change
 * @val: pointer to data to set the property value to
 * @len: length of the property value
 *
 * fdt_setprop() sets the value of the named property in the given
 * node to the given value and length, creating the property if it
 * does not already exist.
 *
 * This function may insert or delete data from the blob, and will
 * therefore change the offsets of some existing nodes.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 *		contain the new property value
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
int fdt_setprop(void *fdt, int nodeoffset, const char *name,
		const void *val, int len);

/**
 * fdt_setprop_u32 - set a property to a 32-bit integer
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to change
 * @name: name of the property to change
 * @val: 32-bit integer value for the property (native endian)
 *
 * fdt_setprop_u32() sets the value of the named property in the given
 * node to the given 32-bit integer value (converting to big-endian if
 * necessary), or creates a new property with that value if it does
 * not already exist.
 *
 * This function may insert or delete data from the blob, and will
 * therefore change the offsets of some existing nodes.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 *		contain the new property value
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
static inline int fdt_setprop_u32(void *fdt, int nodeoffset, const char *name,
				  uint32_t val)
{
	val = cpu_to_fdt32(val);
	return fdt_setprop(fdt, nodeoffset, name, &val, sizeof(val));
}

/**
 * fdt_setprop_u64 - set a property to a 64-bit integer
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to change
 * @name: name of the property to change
 * @val: 64-bit integer value for the property (native endian)
 *
 * fdt_setprop_u64() sets the value of the named property in the given
 * node to the given 64-bit integer value (converting to big-endian if
 * necessary), or creates a new property with that value if it does
 * not already exist.
 *
 * This function may insert or delete data from the blob, and will
 * therefore change the offsets of some existing nodes.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 *		contain the new property value
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
static inline int fdt_setprop_u64(void *fdt, int nodeoffset, const char *name,
				  uint64_t val)
{
	val = cpu_to_fdt64(val);
	return fdt_setprop(fdt, nodeoffset, name, &val, sizeof(val));
}

/**
 * fdt_setprop_cell - set a property to a single cell value
 *
 * This is an alternative name for fdt_setprop_u32()
 */
static inline int fdt_setprop_cell(void *fdt, int nodeoffset, const char *name,
				   uint32_t val)
{
	return fdt_setprop_u32(fdt, nodeoffset, name, val);
}

/**
 * fdt_setprop_string - set a property to a string value
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to change
 * @name: name of the property to change
 * @str: string value for the property
 *
 * fdt_setprop_string() sets the value of the named property in the
 * given node to the given string value (using the length of the
 * string to determine the new length of the property), or creates a
 * new property with that value if it does not already exist.
 *
 * This function may insert or delete data from the blob, and will
 * therefore change the offsets of some existing nodes.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 *		contain the new property value
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
#define fdt_setprop_string(fdt, nodeoffset, name, str) \
	fdt_setprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)

/**
 * fdt_appendprop - append to or create a property
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to change
 * @name: name of the property to append to
 * @val: pointer to data to append to the property value
 * @len: length of the data to append to the property value
 *
 * fdt_appendprop() appends the value to the named property in the
 * given node, creating the property if it does not already exist.
 *
 * This function may insert data into the blob, and will therefore
 * change the offsets of some existing nodes.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 *		contain the new property value
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
		   const void *val, int len);

/**
 * fdt_appendprop_u32 - append a 32-bit integer value to a property
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to change
 * @name: name of the property to change
 * @val: 32-bit integer value to append to the property (native endian)
 *
 * fdt_appendprop_u32() appends the given 32-bit integer value
 * (converting to big-endian if necessary) to the value of the named
 * property in the given node, or creates a new property with that
 * value if it does not already exist.
 *
 * This function may insert data into the blob, and will therefore
 * change the offsets of some existing nodes.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 *		contain the new property value
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
static inline int fdt_appendprop_u32(void *fdt, int nodeoffset,
				     const char *name, uint32_t val)
{
	val = cpu_to_fdt32(val);
	return fdt_appendprop(fdt, nodeoffset, name, &val, sizeof(val));
}

/**
 * fdt_appendprop_u64 - append a 64-bit integer value to a property
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to change
 * @name: name of the property to change
 * @val: 64-bit integer value to append to the property (native endian)
 *
 * fdt_appendprop_u64() appends the given 64-bit integer value
 * (converting to big-endian if necessary) to the value of the named
 * property in the given node, or creates a new property with that
 * value if it does not already exist.
 *
 * This function may insert data into the blob, and will therefore
 * change the offsets of some existing nodes.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 *		contain the new property value
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
static inline int fdt_appendprop_u64(void *fdt, int nodeoffset,
				     const char *name, uint64_t val)
{
	val = cpu_to_fdt64(val);
	return fdt_appendprop(fdt, nodeoffset, name, &val, sizeof(val));
}

/**
 * fdt_appendprop_cell - append a single cell value to a property
 *
 * This is an alternative name for fdt_appendprop_u32()
 */
static inline int fdt_appendprop_cell(void *fdt, int nodeoffset,
				      const char *name, uint32_t val)
{
	return fdt_appendprop_u32(fdt, nodeoffset, name, val);
}

/**
 * fdt_appendprop_string - append a string to a property
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to change
 * @name: name of the property to change
 * @str: string value to append to the property
 *
 * fdt_appendprop_string() appends the given string to the value of
 * the named property in the given node, or creates a new property
 * with that value if it does not already exist.
 *
 * This function may insert data into the blob, and will therefore
 * change the offsets of some existing nodes.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOSPACE, there is insufficient free space in the blob to
 *		contain the new property value
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
#define fdt_appendprop_string(fdt, nodeoffset, name, str) \
	fdt_appendprop((fdt), (nodeoffset), (name), (str), strlen(str)+1)

/**
 * fdt_delprop - delete a property
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node whose property to nop
 * @name: name of the property to nop
 *
 * fdt_del_property() will delete the given property.
 *
 * This function will delete data from the blob, and will therefore
 * change the offsets of some existing nodes.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_NOTFOUND, node does not have the named property
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
int fdt_delprop(void *fdt, int nodeoffset, const char *name);

/**
 * fdt_add_subnode_namelen - creates a new node based on substring
 * @fdt: pointer to the device tree blob
 * @parentoffset: structure block offset of a node
 * @name: name of the subnode to locate
 * @namelen: number of characters of name to consider
 *
 * Identical to fdt_add_subnode(), but use only the first namelen
 * characters of name as the name of the new node.  This is useful for
 * creating subnodes based on a portion of a larger string, such as a
 * full path.
 */
int fdt_add_subnode_namelen(void *fdt, int parentoffset,
			    const char *name, int namelen);

/**
 * fdt_add_subnode - creates a new node
 * @fdt: pointer to the device tree blob
 * @parentoffset: structure block offset of a node
 * @name: name of the subnode to locate
 *
 * fdt_add_subnode() creates a new node as a subnode of the node at
 * structure block offset parentoffset, with the given name (which
 * should include the unit address, if any).
 *
 * This function will insert data into the blob, and will therefore
 * change the offsets of some existing nodes.

 * returns:
 *	structure block offset of the created nodeequested subnode (>=0), on success
 *	-FDT_ERR_NOTFOUND, if the requested subnode does not exist
 *	-FDT_ERR_BADOFFSET, if parentoffset did not point to an FDT_BEGIN_NODE tag
 *	-FDT_ERR_EXISTS, if the node at parentoffset already has a subnode of
 *		the given name
 *	-FDT_ERR_NOSPACE, if there is insufficient free space in the
 *		blob to contain the new node
 *	-FDT_ERR_NOSPACE
 *	-FDT_ERR_BADLAYOUT
 *      -FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_TRUNCATED, standard meanings.
 */
int fdt_add_subnode(void *fdt, int parentoffset, const char *name);

/**
 * fdt_del_node - delete a node (subtree)
 * @fdt: pointer to the device tree blob
 * @nodeoffset: offset of the node to nop
 *
 * fdt_del_node() will remove the given node, including all its
 * subnodes if any, from the blob.
 *
 * This function will delete data from the blob, and will therefore
 * change the offsets of some existing nodes.
 *
 * returns:
 *	0, on success
 *	-FDT_ERR_BADOFFSET, nodeoffset did not point to FDT_BEGIN_NODE tag
 *	-FDT_ERR_BADLAYOUT,
 *	-FDT_ERR_BADMAGIC,
 *	-FDT_ERR_BADVERSION,
 *	-FDT_ERR_BADSTATE,
 *	-FDT_ERR_BADSTRUCTURE,
 *	-FDT_ERR_TRUNCATED, standard meanings
 */
int fdt_del_node(void *fdt, int nodeoffset);

/**********************************************************************/
/* Debugging / informational functions                                */
/**********************************************************************/

const char *fdt_strerror(int errval);

#endif /* _LIBFDT_H */