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1// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
2/*
3 * libfdt - Flat Device Tree manipulation
4 * Copyright (C) 2006 David Gibson, IBM Corporation.
5 */
6#include "libfdt_env.h"
7
8#include <fdt.h>
9#include <libfdt.h>
10
11#include "libfdt_internal.h"
12
13static int fdt_nodename_eq_(const void *fdt, int offset,
14 const char *s, int len)
15{
16 int olen;
17 const char *p = fdt_get_name(fdt, offset, &olen);
18
19 if (!p || olen < len)
20 /* short match */
21 return 0;
22
23 if (memcmp(p, s, len) != 0)
24 return 0;
25
26 if (p[len] == '\0')
27 return 1;
28 else if (!memchr(s, '@', len) && (p[len] == '@'))
29 return 1;
30 else
31 return 0;
32}
33
34const char *fdt_get_string(const void *fdt, int stroffset, int *lenp)
35{
36 uint32_t absoffset = stroffset + fdt_off_dt_strings(fdt);
37 size_t len;
38 int err;
39 const char *s, *n;
40
41 err = fdt_ro_probe_(fdt);
42 if (err != 0)
43 goto fail;
44
45 err = -FDT_ERR_BADOFFSET;
46 if (absoffset >= fdt_totalsize(fdt))
47 goto fail;
48 len = fdt_totalsize(fdt) - absoffset;
49
50 if (fdt_magic(fdt) == FDT_MAGIC) {
51 if (stroffset < 0)
52 goto fail;
53 if (fdt_version(fdt) >= 17) {
54 if (stroffset >= fdt_size_dt_strings(fdt))
55 goto fail;
56 if ((fdt_size_dt_strings(fdt) - stroffset) < len)
57 len = fdt_size_dt_strings(fdt) - stroffset;
58 }
59 } else if (fdt_magic(fdt) == FDT_SW_MAGIC) {
60 if ((stroffset >= 0)
61 || (stroffset < -fdt_size_dt_strings(fdt)))
62 goto fail;
63 if ((-stroffset) < len)
64 len = -stroffset;
65 } else {
66 err = -FDT_ERR_INTERNAL;
67 goto fail;
68 }
69
70 s = (const char *)fdt + absoffset;
71 n = memchr(s, '\0', len);
72 if (!n) {
73 /* missing terminating NULL */
74 err = -FDT_ERR_TRUNCATED;
75 goto fail;
76 }
77
78 if (lenp)
79 *lenp = n - s;
80 return s;
81
82fail:
83 if (lenp)
84 *lenp = err;
85 return NULL;
86}
87
88const char *fdt_string(const void *fdt, int stroffset)
89{
90 return fdt_get_string(fdt, stroffset, NULL);
91}
92
93static int fdt_string_eq_(const void *fdt, int stroffset,
94 const char *s, int len)
95{
96 int slen;
97 const char *p = fdt_get_string(fdt, stroffset, &slen);
98
99 return p && (slen == len) && (memcmp(p, s, len) == 0);
100}
101
102int fdt_find_max_phandle(const void *fdt, uint32_t *phandle)
103{
104 uint32_t max = 0;
105 int offset = -1;
106
107 while (true) {
108 uint32_t value;
109
110 offset = fdt_next_node(fdt, offset, NULL);
111 if (offset < 0) {
112 if (offset == -FDT_ERR_NOTFOUND)
113 break;
114
115 return offset;
116 }
117
118 value = fdt_get_phandle(fdt, offset);
119
120 if (value > max)
121 max = value;
122 }
123
124 if (phandle)
125 *phandle = max;
126
127 return 0;
128}
129
130int fdt_generate_phandle(const void *fdt, uint32_t *phandle)
131{
132 uint32_t max;
133 int err;
134
135 err = fdt_find_max_phandle(fdt, &max);
136 if (err < 0)
137 return err;
138
139 if (max == FDT_MAX_PHANDLE)
140 return -FDT_ERR_NOPHANDLES;
141
142 if (phandle)
143 *phandle = max + 1;
144
145 return 0;
146}
147
148static const struct fdt_reserve_entry *fdt_mem_rsv(const void *fdt, int n)
149{
150 int offset = n * sizeof(struct fdt_reserve_entry);
151 int absoffset = fdt_off_mem_rsvmap(fdt) + offset;
152
153 if (absoffset < fdt_off_mem_rsvmap(fdt))
154 return NULL;
155 if (absoffset > fdt_totalsize(fdt) - sizeof(struct fdt_reserve_entry))
156 return NULL;
157 return fdt_mem_rsv_(fdt, n);
158}
159
160int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size)
161{
162 const struct fdt_reserve_entry *re;
163
164 FDT_RO_PROBE(fdt);
165 re = fdt_mem_rsv(fdt, n);
166 if (!re)
167 return -FDT_ERR_BADOFFSET;
168
169 *address = fdt64_ld(&re->address);
170 *size = fdt64_ld(&re->size);
171 return 0;
172}
173
174int fdt_num_mem_rsv(const void *fdt)
175{
176 int i;
177 const struct fdt_reserve_entry *re;
178
179 for (i = 0; (re = fdt_mem_rsv(fdt, i)) != NULL; i++) {
180 if (fdt64_ld(&re->size) == 0)
181 return i;
182 }
183 return -FDT_ERR_TRUNCATED;
184}
185
186static int nextprop_(const void *fdt, int offset)
187{
188 uint32_t tag;
189 int nextoffset;
190
191 do {
192 tag = fdt_next_tag(fdt, offset, &nextoffset);
193
194 switch (tag) {
195 case FDT_END:
196 if (nextoffset >= 0)
197 return -FDT_ERR_BADSTRUCTURE;
198 else
199 return nextoffset;
200
201 case FDT_PROP:
202 return offset;
203 }
204 offset = nextoffset;
205 } while (tag == FDT_NOP);
206
207 return -FDT_ERR_NOTFOUND;
208}
209
210int fdt_subnode_offset_namelen(const void *fdt, int offset,
211 const char *name, int namelen)
212{
213 int depth;
214
215 FDT_RO_PROBE(fdt);
216
217 for (depth = 0;
218 (offset >= 0) && (depth >= 0);
219 offset = fdt_next_node(fdt, offset, &depth))
220 if ((depth == 1)
221 && fdt_nodename_eq_(fdt, offset, name, namelen))
222 return offset;
223
224 if (depth < 0)
225 return -FDT_ERR_NOTFOUND;
226 return offset; /* error */
227}
228
229int fdt_subnode_offset(const void *fdt, int parentoffset,
230 const char *name)
231{
232 return fdt_subnode_offset_namelen(fdt, parentoffset, name, strlen(name));
233}
234
235int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen)
236{
237 const char *end = path + namelen;
238 const char *p = path;
239 int offset = 0;
240
241 FDT_RO_PROBE(fdt);
242
243 /* see if we have an alias */
244 if (*path != '/') {
245 const char *q = memchr(path, '/', end - p);
246
247 if (!q)
248 q = end;
249
250 p = fdt_get_alias_namelen(fdt, p, q - p);
251 if (!p)
252 return -FDT_ERR_BADPATH;
253 offset = fdt_path_offset(fdt, p);
254
255 p = q;
256 }
257
258 while (p < end) {
259 const char *q;
260
261 while (*p == '/') {
262 p++;
263 if (p == end)
264 return offset;
265 }
266 q = memchr(p, '/', end - p);
267 if (! q)
268 q = end;
269
270 offset = fdt_subnode_offset_namelen(fdt, offset, p, q-p);
271 if (offset < 0)
272 return offset;
273
274 p = q;
275 }
276
277 return offset;
278}
279
280int fdt_path_offset(const void *fdt, const char *path)
281{
282 return fdt_path_offset_namelen(fdt, path, strlen(path));
283}
284
285const char *fdt_get_name(const void *fdt, int nodeoffset, int *len)
286{
287 const struct fdt_node_header *nh = fdt_offset_ptr_(fdt, nodeoffset);
288 const char *nameptr;
289 int err;
290
291 if (((err = fdt_ro_probe_(fdt)) != 0)
292 || ((err = fdt_check_node_offset_(fdt, nodeoffset)) < 0))
293 goto fail;
294
295 nameptr = nh->name;
296
297 if (fdt_version(fdt) < 0x10) {
298 /*
299 * For old FDT versions, match the naming conventions of V16:
300 * give only the leaf name (after all /). The actual tree
301 * contents are loosely checked.
302 */
303 const char *leaf;
304 leaf = strrchr(nameptr, '/');
305 if (leaf == NULL) {
306 err = -FDT_ERR_BADSTRUCTURE;
307 goto fail;
308 }
309 nameptr = leaf+1;
310 }
311
312 if (len)
313 *len = strlen(nameptr);
314
315 return nameptr;
316
317 fail:
318 if (len)
319 *len = err;
320 return NULL;
321}
322
323int fdt_first_property_offset(const void *fdt, int nodeoffset)
324{
325 int offset;
326
327 if ((offset = fdt_check_node_offset_(fdt, nodeoffset)) < 0)
328 return offset;
329
330 return nextprop_(fdt, offset);
331}
332
333int fdt_next_property_offset(const void *fdt, int offset)
334{
335 if ((offset = fdt_check_prop_offset_(fdt, offset)) < 0)
336 return offset;
337
338 return nextprop_(fdt, offset);
339}
340
341static const struct fdt_property *fdt_get_property_by_offset_(const void *fdt,
342 int offset,
343 int *lenp)
344{
345 int err;
346 const struct fdt_property *prop;
347
348 if ((err = fdt_check_prop_offset_(fdt, offset)) < 0) {
349 if (lenp)
350 *lenp = err;
351 return NULL;
352 }
353
354 prop = fdt_offset_ptr_(fdt, offset);
355
356 if (lenp)
357 *lenp = fdt32_ld(&prop->len);
358
359 return prop;
360}
361
362const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
363 int offset,
364 int *lenp)
365{
366 /* Prior to version 16, properties may need realignment
367 * and this API does not work. fdt_getprop_*() will, however. */
368
369 if (fdt_version(fdt) < 0x10) {
370 if (lenp)
371 *lenp = -FDT_ERR_BADVERSION;
372 return NULL;
373 }
374
375 return fdt_get_property_by_offset_(fdt, offset, lenp);
376}
377
378static const struct fdt_property *fdt_get_property_namelen_(const void *fdt,
379 int offset,
380 const char *name,
381 int namelen,
382 int *lenp,
383 int *poffset)
384{
385 for (offset = fdt_first_property_offset(fdt, offset);
386 (offset >= 0);
387 (offset = fdt_next_property_offset(fdt, offset))) {
388 const struct fdt_property *prop;
389
390 if (!(prop = fdt_get_property_by_offset_(fdt, offset, lenp))) {
391 offset = -FDT_ERR_INTERNAL;
392 break;
393 }
394 if (fdt_string_eq_(fdt, fdt32_ld(&prop->nameoff),
395 name, namelen)) {
396 if (poffset)
397 *poffset = offset;
398 return prop;
399 }
400 }
401
402 if (lenp)
403 *lenp = offset;
404 return NULL;
405}
406
407
408const struct fdt_property *fdt_get_property_namelen(const void *fdt,
409 int offset,
410 const char *name,
411 int namelen, int *lenp)
412{
413 /* Prior to version 16, properties may need realignment
414 * and this API does not work. fdt_getprop_*() will, however. */
415 if (fdt_version(fdt) < 0x10) {
416 if (lenp)
417 *lenp = -FDT_ERR_BADVERSION;
418 return NULL;
419 }
420
421 return fdt_get_property_namelen_(fdt, offset, name, namelen, lenp,
422 NULL);
423}
424
425
426const struct fdt_property *fdt_get_property(const void *fdt,
427 int nodeoffset,
428 const char *name, int *lenp)
429{
430 return fdt_get_property_namelen(fdt, nodeoffset, name,
431 strlen(name), lenp);
432}
433
434const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
435 const char *name, int namelen, int *lenp)
436{
437 int poffset;
438 const struct fdt_property *prop;
439
440 prop = fdt_get_property_namelen_(fdt, nodeoffset, name, namelen, lenp,
441 &poffset);
442 if (!prop)
443 return NULL;
444
445 /* Handle realignment */
446 if (fdt_version(fdt) < 0x10 && (poffset + sizeof(*prop)) % 8 &&
447 fdt32_ld(&prop->len) >= 8)
448 return prop->data + 4;
449 return prop->data;
450}
451
452const void *fdt_getprop_by_offset(const void *fdt, int offset,
453 const char **namep, int *lenp)
454{
455 const struct fdt_property *prop;
456
457 prop = fdt_get_property_by_offset_(fdt, offset, lenp);
458 if (!prop)
459 return NULL;
460 if (namep) {
461 const char *name;
462 int namelen;
463 name = fdt_get_string(fdt, fdt32_ld(&prop->nameoff),
464 &namelen);
465 if (!name) {
466 if (lenp)
467 *lenp = namelen;
468 return NULL;
469 }
470 *namep = name;
471 }
472
473 /* Handle realignment */
474 if (fdt_version(fdt) < 0x10 && (offset + sizeof(*prop)) % 8 &&
475 fdt32_ld(&prop->len) >= 8)
476 return prop->data + 4;
477 return prop->data;
478}
479
480const void *fdt_getprop(const void *fdt, int nodeoffset,
481 const char *name, int *lenp)
482{
483 return fdt_getprop_namelen(fdt, nodeoffset, name, strlen(name), lenp);
484}
485
486uint32_t fdt_get_phandle(const void *fdt, int nodeoffset)
487{
488 const fdt32_t *php;
489 int len;
490
491 /* FIXME: This is a bit sub-optimal, since we potentially scan
492 * over all the properties twice. */
493 php = fdt_getprop(fdt, nodeoffset, "phandle", &len);
494 if (!php || (len != sizeof(*php))) {
495 php = fdt_getprop(fdt, nodeoffset, "linux,phandle", &len);
496 if (!php || (len != sizeof(*php)))
497 return 0;
498 }
499
500 return fdt32_ld(php);
501}
502
503const char *fdt_get_alias_namelen(const void *fdt,
504 const char *name, int namelen)
505{
506 int aliasoffset;
507
508 aliasoffset = fdt_path_offset(fdt, "/aliases");
509 if (aliasoffset < 0)
510 return NULL;
511
512 return fdt_getprop_namelen(fdt, aliasoffset, name, namelen, NULL);
513}
514
515const char *fdt_get_alias(const void *fdt, const char *name)
516{
517 return fdt_get_alias_namelen(fdt, name, strlen(name));
518}
519
520int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen)
521{
522 int pdepth = 0, p = 0;
523 int offset, depth, namelen;
524 const char *name;
525
526 FDT_RO_PROBE(fdt);
527
528 if (buflen < 2)
529 return -FDT_ERR_NOSPACE;
530
531 for (offset = 0, depth = 0;
532 (offset >= 0) && (offset <= nodeoffset);
533 offset = fdt_next_node(fdt, offset, &depth)) {
534 while (pdepth > depth) {
535 do {
536 p--;
537 } while (buf[p-1] != '/');
538 pdepth--;
539 }
540
541 if (pdepth >= depth) {
542 name = fdt_get_name(fdt, offset, &namelen);
543 if (!name)
544 return namelen;
545 if ((p + namelen + 1) <= buflen) {
546 memcpy(buf + p, name, namelen);
547 p += namelen;
548 buf[p++] = '/';
549 pdepth++;
550 }
551 }
552
553 if (offset == nodeoffset) {
554 if (pdepth < (depth + 1))
555 return -FDT_ERR_NOSPACE;
556
557 if (p > 1) /* special case so that root path is "/", not "" */
558 p--;
559 buf[p] = '\0';
560 return 0;
561 }
562 }
563
564 if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
565 return -FDT_ERR_BADOFFSET;
566 else if (offset == -FDT_ERR_BADOFFSET)
567 return -FDT_ERR_BADSTRUCTURE;
568
569 return offset; /* error from fdt_next_node() */
570}
571
572int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
573 int supernodedepth, int *nodedepth)
574{
575 int offset, depth;
576 int supernodeoffset = -FDT_ERR_INTERNAL;
577
578 FDT_RO_PROBE(fdt);
579
580 if (supernodedepth < 0)
581 return -FDT_ERR_NOTFOUND;
582
583 for (offset = 0, depth = 0;
584 (offset >= 0) && (offset <= nodeoffset);
585 offset = fdt_next_node(fdt, offset, &depth)) {
586 if (depth == supernodedepth)
587 supernodeoffset = offset;
588
589 if (offset == nodeoffset) {
590 if (nodedepth)
591 *nodedepth = depth;
592
593 if (supernodedepth > depth)
594 return -FDT_ERR_NOTFOUND;
595 else
596 return supernodeoffset;
597 }
598 }
599
600 if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
601 return -FDT_ERR_BADOFFSET;
602 else if (offset == -FDT_ERR_BADOFFSET)
603 return -FDT_ERR_BADSTRUCTURE;
604
605 return offset; /* error from fdt_next_node() */
606}
607
608int fdt_node_depth(const void *fdt, int nodeoffset)
609{
610 int nodedepth;
611 int err;
612
613 err = fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, &nodedepth);
614 if (err)
615 return (err < 0) ? err : -FDT_ERR_INTERNAL;
616 return nodedepth;
617}
618
619int fdt_parent_offset(const void *fdt, int nodeoffset)
620{
621 int nodedepth = fdt_node_depth(fdt, nodeoffset);
622
623 if (nodedepth < 0)
624 return nodedepth;
625 return fdt_supernode_atdepth_offset(fdt, nodeoffset,
626 nodedepth - 1, NULL);
627}
628
629int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
630 const char *propname,
631 const void *propval, int proplen)
632{
633 int offset;
634 const void *val;
635 int len;
636
637 FDT_RO_PROBE(fdt);
638
639 /* FIXME: The algorithm here is pretty horrible: we scan each
640 * property of a node in fdt_getprop(), then if that didn't
641 * find what we want, we scan over them again making our way
642 * to the next node. Still it's the easiest to implement
643 * approach; performance can come later. */
644 for (offset = fdt_next_node(fdt, startoffset, NULL);
645 offset >= 0;
646 offset = fdt_next_node(fdt, offset, NULL)) {
647 val = fdt_getprop(fdt, offset, propname, &len);
648 if (val && (len == proplen)
649 && (memcmp(val, propval, len) == 0))
650 return offset;
651 }
652
653 return offset; /* error from fdt_next_node() */
654}
655
656int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle)
657{
658 int offset;
659
660 if ((phandle == 0) || (phandle == -1))
661 return -FDT_ERR_BADPHANDLE;
662
663 FDT_RO_PROBE(fdt);
664
665 /* FIXME: The algorithm here is pretty horrible: we
666 * potentially scan each property of a node in
667 * fdt_get_phandle(), then if that didn't find what
668 * we want, we scan over them again making our way to the next
669 * node. Still it's the easiest to implement approach;
670 * performance can come later. */
671 for (offset = fdt_next_node(fdt, -1, NULL);
672 offset >= 0;
673 offset = fdt_next_node(fdt, offset, NULL)) {
674 if (fdt_get_phandle(fdt, offset) == phandle)
675 return offset;
676 }
677
678 return offset; /* error from fdt_next_node() */
679}
680
681int fdt_stringlist_contains(const char *strlist, int listlen, const char *str)
682{
683 int len = strlen(str);
684 const char *p;
685
686 while (listlen >= len) {
687 if (memcmp(str, strlist, len+1) == 0)
688 return 1;
689 p = memchr(strlist, '\0', listlen);
690 if (!p)
691 return 0; /* malformed strlist.. */
692 listlen -= (p-strlist) + 1;
693 strlist = p + 1;
694 }
695 return 0;
696}
697
698int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property)
699{
700 const char *list, *end;
701 int length, count = 0;
702
703 list = fdt_getprop(fdt, nodeoffset, property, &length);
704 if (!list)
705 return length;
706
707 end = list + length;
708
709 while (list < end) {
710 length = strnlen(list, end - list) + 1;
711
712 /* Abort if the last string isn't properly NUL-terminated. */
713 if (list + length > end)
714 return -FDT_ERR_BADVALUE;
715
716 list += length;
717 count++;
718 }
719
720 return count;
721}
722
723int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
724 const char *string)
725{
726 int length, len, idx = 0;
727 const char *list, *end;
728
729 list = fdt_getprop(fdt, nodeoffset, property, &length);
730 if (!list)
731 return length;
732
733 len = strlen(string) + 1;
734 end = list + length;
735
736 while (list < end) {
737 length = strnlen(list, end - list) + 1;
738
739 /* Abort if the last string isn't properly NUL-terminated. */
740 if (list + length > end)
741 return -FDT_ERR_BADVALUE;
742
743 if (length == len && memcmp(list, string, length) == 0)
744 return idx;
745
746 list += length;
747 idx++;
748 }
749
750 return -FDT_ERR_NOTFOUND;
751}
752
753const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
754 const char *property, int idx,
755 int *lenp)
756{
757 const char *list, *end;
758 int length;
759
760 list = fdt_getprop(fdt, nodeoffset, property, &length);
761 if (!list) {
762 if (lenp)
763 *lenp = length;
764
765 return NULL;
766 }
767
768 end = list + length;
769
770 while (list < end) {
771 length = strnlen(list, end - list) + 1;
772
773 /* Abort if the last string isn't properly NUL-terminated. */
774 if (list + length > end) {
775 if (lenp)
776 *lenp = -FDT_ERR_BADVALUE;
777
778 return NULL;
779 }
780
781 if (idx == 0) {
782 if (lenp)
783 *lenp = length - 1;
784
785 return list;
786 }
787
788 list += length;
789 idx--;
790 }
791
792 if (lenp)
793 *lenp = -FDT_ERR_NOTFOUND;
794
795 return NULL;
796}
797
798int fdt_node_check_compatible(const void *fdt, int nodeoffset,
799 const char *compatible)
800{
801 const void *prop;
802 int len;
803
804 prop = fdt_getprop(fdt, nodeoffset, "compatible", &len);
805 if (!prop)
806 return len;
807
808 return !fdt_stringlist_contains(prop, len, compatible);
809}
810
811int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
812 const char *compatible)
813{
814 int offset, err;
815
816 FDT_RO_PROBE(fdt);
817
818 /* FIXME: The algorithm here is pretty horrible: we scan each
819 * property of a node in fdt_node_check_compatible(), then if
820 * that didn't find what we want, we scan over them again
821 * making our way to the next node. Still it's the easiest to
822 * implement approach; performance can come later. */
823 for (offset = fdt_next_node(fdt, startoffset, NULL);
824 offset >= 0;
825 offset = fdt_next_node(fdt, offset, NULL)) {
826 err = fdt_node_check_compatible(fdt, offset, compatible);
827 if ((err < 0) && (err != -FDT_ERR_NOTFOUND))
828 return err;
829 else if (err == 0)
830 return offset;
831 }
832
833 return offset; /* error from fdt_next_node() */
834}
835
836int fdt_check_full(const void *fdt, size_t bufsize)
837{
838 int err;
839 int num_memrsv;
840 int offset, nextoffset = 0;
841 uint32_t tag;
842 unsigned depth = 0;
843 const void *prop;
844 const char *propname;
845
846 if (bufsize < FDT_V1_SIZE)
847 return -FDT_ERR_TRUNCATED;
848 err = fdt_check_header(fdt);
849 if (err != 0)
850 return err;
851 if (bufsize < fdt_totalsize(fdt))
852 return -FDT_ERR_TRUNCATED;
853
854 num_memrsv = fdt_num_mem_rsv(fdt);
855 if (num_memrsv < 0)
856 return num_memrsv;
857
858 while (1) {
859 offset = nextoffset;
860 tag = fdt_next_tag(fdt, offset, &nextoffset);
861
862 if (nextoffset < 0)
863 return nextoffset;
864
865 switch (tag) {
866 case FDT_NOP:
867 break;
868
869 case FDT_END:
870 if (depth != 0)
871 return -FDT_ERR_BADSTRUCTURE;
872 return 0;
873
874 case FDT_BEGIN_NODE:
875 depth++;
876 if (depth > INT_MAX)
877 return -FDT_ERR_BADSTRUCTURE;
878 break;
879
880 case FDT_END_NODE:
881 if (depth == 0)
882 return -FDT_ERR_BADSTRUCTURE;
883 depth--;
884 break;
885
886 case FDT_PROP:
887 prop = fdt_getprop_by_offset(fdt, offset, &propname,
888 &err);
889 if (!prop)
890 return err;
891 break;
892
893 default:
894 return -FDT_ERR_INTERNAL;
895 }
896 }
897}
1/*
2 * libfdt - Flat Device Tree manipulation
3 * Copyright (C) 2006 David Gibson, IBM Corporation.
4 *
5 * libfdt is dual licensed: you can use it either under the terms of
6 * the GPL, or the BSD license, at your option.
7 *
8 * a) This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of the
11 * License, or (at your option) any later version.
12 *
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public
19 * License along with this library; if not, write to the Free
20 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
21 * MA 02110-1301 USA
22 *
23 * Alternatively,
24 *
25 * b) Redistribution and use in source and binary forms, with or
26 * without modification, are permitted provided that the following
27 * conditions are met:
28 *
29 * 1. Redistributions of source code must retain the above
30 * copyright notice, this list of conditions and the following
31 * disclaimer.
32 * 2. Redistributions in binary form must reproduce the above
33 * copyright notice, this list of conditions and the following
34 * disclaimer in the documentation and/or other materials
35 * provided with the distribution.
36 *
37 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
38 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
39 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
40 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
41 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
42 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
43 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
44 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
45 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
46 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
47 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
48 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
49 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
50 */
51#include "libfdt_env.h"
52
53#include <fdt.h>
54#include <libfdt.h>
55
56#include "libfdt_internal.h"
57
58static int fdt_nodename_eq_(const void *fdt, int offset,
59 const char *s, int len)
60{
61 int olen;
62 const char *p = fdt_get_name(fdt, offset, &olen);
63
64 if (!p || olen < len)
65 /* short match */
66 return 0;
67
68 if (memcmp(p, s, len) != 0)
69 return 0;
70
71 if (p[len] == '\0')
72 return 1;
73 else if (!memchr(s, '@', len) && (p[len] == '@'))
74 return 1;
75 else
76 return 0;
77}
78
79const char *fdt_string(const void *fdt, int stroffset)
80{
81 return (const char *)fdt + fdt_off_dt_strings(fdt) + stroffset;
82}
83
84static int fdt_string_eq_(const void *fdt, int stroffset,
85 const char *s, int len)
86{
87 const char *p = fdt_string(fdt, stroffset);
88
89 return (strlen(p) == len) && (memcmp(p, s, len) == 0);
90}
91
92uint32_t fdt_get_max_phandle(const void *fdt)
93{
94 uint32_t max_phandle = 0;
95 int offset;
96
97 for (offset = fdt_next_node(fdt, -1, NULL);;
98 offset = fdt_next_node(fdt, offset, NULL)) {
99 uint32_t phandle;
100
101 if (offset == -FDT_ERR_NOTFOUND)
102 return max_phandle;
103
104 if (offset < 0)
105 return (uint32_t)-1;
106
107 phandle = fdt_get_phandle(fdt, offset);
108 if (phandle == (uint32_t)-1)
109 continue;
110
111 if (phandle > max_phandle)
112 max_phandle = phandle;
113 }
114
115 return 0;
116}
117
118int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size)
119{
120 FDT_CHECK_HEADER(fdt);
121 *address = fdt64_to_cpu(fdt_mem_rsv_(fdt, n)->address);
122 *size = fdt64_to_cpu(fdt_mem_rsv_(fdt, n)->size);
123 return 0;
124}
125
126int fdt_num_mem_rsv(const void *fdt)
127{
128 int i = 0;
129
130 while (fdt64_to_cpu(fdt_mem_rsv_(fdt, i)->size) != 0)
131 i++;
132 return i;
133}
134
135static int nextprop_(const void *fdt, int offset)
136{
137 uint32_t tag;
138 int nextoffset;
139
140 do {
141 tag = fdt_next_tag(fdt, offset, &nextoffset);
142
143 switch (tag) {
144 case FDT_END:
145 if (nextoffset >= 0)
146 return -FDT_ERR_BADSTRUCTURE;
147 else
148 return nextoffset;
149
150 case FDT_PROP:
151 return offset;
152 }
153 offset = nextoffset;
154 } while (tag == FDT_NOP);
155
156 return -FDT_ERR_NOTFOUND;
157}
158
159int fdt_subnode_offset_namelen(const void *fdt, int offset,
160 const char *name, int namelen)
161{
162 int depth;
163
164 FDT_CHECK_HEADER(fdt);
165
166 for (depth = 0;
167 (offset >= 0) && (depth >= 0);
168 offset = fdt_next_node(fdt, offset, &depth))
169 if ((depth == 1)
170 && fdt_nodename_eq_(fdt, offset, name, namelen))
171 return offset;
172
173 if (depth < 0)
174 return -FDT_ERR_NOTFOUND;
175 return offset; /* error */
176}
177
178int fdt_subnode_offset(const void *fdt, int parentoffset,
179 const char *name)
180{
181 return fdt_subnode_offset_namelen(fdt, parentoffset, name, strlen(name));
182}
183
184int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen)
185{
186 const char *end = path + namelen;
187 const char *p = path;
188 int offset = 0;
189
190 FDT_CHECK_HEADER(fdt);
191
192 /* see if we have an alias */
193 if (*path != '/') {
194 const char *q = memchr(path, '/', end - p);
195
196 if (!q)
197 q = end;
198
199 p = fdt_get_alias_namelen(fdt, p, q - p);
200 if (!p)
201 return -FDT_ERR_BADPATH;
202 offset = fdt_path_offset(fdt, p);
203
204 p = q;
205 }
206
207 while (p < end) {
208 const char *q;
209
210 while (*p == '/') {
211 p++;
212 if (p == end)
213 return offset;
214 }
215 q = memchr(p, '/', end - p);
216 if (! q)
217 q = end;
218
219 offset = fdt_subnode_offset_namelen(fdt, offset, p, q-p);
220 if (offset < 0)
221 return offset;
222
223 p = q;
224 }
225
226 return offset;
227}
228
229int fdt_path_offset(const void *fdt, const char *path)
230{
231 return fdt_path_offset_namelen(fdt, path, strlen(path));
232}
233
234const char *fdt_get_name(const void *fdt, int nodeoffset, int *len)
235{
236 const struct fdt_node_header *nh = fdt_offset_ptr_(fdt, nodeoffset);
237 const char *nameptr;
238 int err;
239
240 if (((err = fdt_check_header(fdt)) != 0)
241 || ((err = fdt_check_node_offset_(fdt, nodeoffset)) < 0))
242 goto fail;
243
244 nameptr = nh->name;
245
246 if (fdt_version(fdt) < 0x10) {
247 /*
248 * For old FDT versions, match the naming conventions of V16:
249 * give only the leaf name (after all /). The actual tree
250 * contents are loosely checked.
251 */
252 const char *leaf;
253 leaf = strrchr(nameptr, '/');
254 if (leaf == NULL) {
255 err = -FDT_ERR_BADSTRUCTURE;
256 goto fail;
257 }
258 nameptr = leaf+1;
259 }
260
261 if (len)
262 *len = strlen(nameptr);
263
264 return nameptr;
265
266 fail:
267 if (len)
268 *len = err;
269 return NULL;
270}
271
272int fdt_first_property_offset(const void *fdt, int nodeoffset)
273{
274 int offset;
275
276 if ((offset = fdt_check_node_offset_(fdt, nodeoffset)) < 0)
277 return offset;
278
279 return nextprop_(fdt, offset);
280}
281
282int fdt_next_property_offset(const void *fdt, int offset)
283{
284 if ((offset = fdt_check_prop_offset_(fdt, offset)) < 0)
285 return offset;
286
287 return nextprop_(fdt, offset);
288}
289
290static const struct fdt_property *fdt_get_property_by_offset_(const void *fdt,
291 int offset,
292 int *lenp)
293{
294 int err;
295 const struct fdt_property *prop;
296
297 if ((err = fdt_check_prop_offset_(fdt, offset)) < 0) {
298 if (lenp)
299 *lenp = err;
300 return NULL;
301 }
302
303 prop = fdt_offset_ptr_(fdt, offset);
304
305 if (lenp)
306 *lenp = fdt32_to_cpu(prop->len);
307
308 return prop;
309}
310
311const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
312 int offset,
313 int *lenp)
314{
315 /* Prior to version 16, properties may need realignment
316 * and this API does not work. fdt_getprop_*() will, however. */
317
318 if (fdt_version(fdt) < 0x10) {
319 if (lenp)
320 *lenp = -FDT_ERR_BADVERSION;
321 return NULL;
322 }
323
324 return fdt_get_property_by_offset_(fdt, offset, lenp);
325}
326
327static const struct fdt_property *fdt_get_property_namelen_(const void *fdt,
328 int offset,
329 const char *name,
330 int namelen,
331 int *lenp,
332 int *poffset)
333{
334 for (offset = fdt_first_property_offset(fdt, offset);
335 (offset >= 0);
336 (offset = fdt_next_property_offset(fdt, offset))) {
337 const struct fdt_property *prop;
338
339 if (!(prop = fdt_get_property_by_offset_(fdt, offset, lenp))) {
340 offset = -FDT_ERR_INTERNAL;
341 break;
342 }
343 if (fdt_string_eq_(fdt, fdt32_to_cpu(prop->nameoff),
344 name, namelen)) {
345 if (poffset)
346 *poffset = offset;
347 return prop;
348 }
349 }
350
351 if (lenp)
352 *lenp = offset;
353 return NULL;
354}
355
356
357const struct fdt_property *fdt_get_property_namelen(const void *fdt,
358 int offset,
359 const char *name,
360 int namelen, int *lenp)
361{
362 /* Prior to version 16, properties may need realignment
363 * and this API does not work. fdt_getprop_*() will, however. */
364 if (fdt_version(fdt) < 0x10) {
365 if (lenp)
366 *lenp = -FDT_ERR_BADVERSION;
367 return NULL;
368 }
369
370 return fdt_get_property_namelen_(fdt, offset, name, namelen, lenp,
371 NULL);
372}
373
374
375const struct fdt_property *fdt_get_property(const void *fdt,
376 int nodeoffset,
377 const char *name, int *lenp)
378{
379 return fdt_get_property_namelen(fdt, nodeoffset, name,
380 strlen(name), lenp);
381}
382
383const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
384 const char *name, int namelen, int *lenp)
385{
386 int poffset;
387 const struct fdt_property *prop;
388
389 prop = fdt_get_property_namelen_(fdt, nodeoffset, name, namelen, lenp,
390 &poffset);
391 if (!prop)
392 return NULL;
393
394 /* Handle realignment */
395 if (fdt_version(fdt) < 0x10 && (poffset + sizeof(*prop)) % 8 &&
396 fdt32_to_cpu(prop->len) >= 8)
397 return prop->data + 4;
398 return prop->data;
399}
400
401const void *fdt_getprop_by_offset(const void *fdt, int offset,
402 const char **namep, int *lenp)
403{
404 const struct fdt_property *prop;
405
406 prop = fdt_get_property_by_offset_(fdt, offset, lenp);
407 if (!prop)
408 return NULL;
409 if (namep)
410 *namep = fdt_string(fdt, fdt32_to_cpu(prop->nameoff));
411
412 /* Handle realignment */
413 if (fdt_version(fdt) < 0x10 && (offset + sizeof(*prop)) % 8 &&
414 fdt32_to_cpu(prop->len) >= 8)
415 return prop->data + 4;
416 return prop->data;
417}
418
419const void *fdt_getprop(const void *fdt, int nodeoffset,
420 const char *name, int *lenp)
421{
422 return fdt_getprop_namelen(fdt, nodeoffset, name, strlen(name), lenp);
423}
424
425uint32_t fdt_get_phandle(const void *fdt, int nodeoffset)
426{
427 const fdt32_t *php;
428 int len;
429
430 /* FIXME: This is a bit sub-optimal, since we potentially scan
431 * over all the properties twice. */
432 php = fdt_getprop(fdt, nodeoffset, "phandle", &len);
433 if (!php || (len != sizeof(*php))) {
434 php = fdt_getprop(fdt, nodeoffset, "linux,phandle", &len);
435 if (!php || (len != sizeof(*php)))
436 return 0;
437 }
438
439 return fdt32_to_cpu(*php);
440}
441
442const char *fdt_get_alias_namelen(const void *fdt,
443 const char *name, int namelen)
444{
445 int aliasoffset;
446
447 aliasoffset = fdt_path_offset(fdt, "/aliases");
448 if (aliasoffset < 0)
449 return NULL;
450
451 return fdt_getprop_namelen(fdt, aliasoffset, name, namelen, NULL);
452}
453
454const char *fdt_get_alias(const void *fdt, const char *name)
455{
456 return fdt_get_alias_namelen(fdt, name, strlen(name));
457}
458
459int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen)
460{
461 int pdepth = 0, p = 0;
462 int offset, depth, namelen;
463 const char *name;
464
465 FDT_CHECK_HEADER(fdt);
466
467 if (buflen < 2)
468 return -FDT_ERR_NOSPACE;
469
470 for (offset = 0, depth = 0;
471 (offset >= 0) && (offset <= nodeoffset);
472 offset = fdt_next_node(fdt, offset, &depth)) {
473 while (pdepth > depth) {
474 do {
475 p--;
476 } while (buf[p-1] != '/');
477 pdepth--;
478 }
479
480 if (pdepth >= depth) {
481 name = fdt_get_name(fdt, offset, &namelen);
482 if (!name)
483 return namelen;
484 if ((p + namelen + 1) <= buflen) {
485 memcpy(buf + p, name, namelen);
486 p += namelen;
487 buf[p++] = '/';
488 pdepth++;
489 }
490 }
491
492 if (offset == nodeoffset) {
493 if (pdepth < (depth + 1))
494 return -FDT_ERR_NOSPACE;
495
496 if (p > 1) /* special case so that root path is "/", not "" */
497 p--;
498 buf[p] = '\0';
499 return 0;
500 }
501 }
502
503 if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
504 return -FDT_ERR_BADOFFSET;
505 else if (offset == -FDT_ERR_BADOFFSET)
506 return -FDT_ERR_BADSTRUCTURE;
507
508 return offset; /* error from fdt_next_node() */
509}
510
511int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
512 int supernodedepth, int *nodedepth)
513{
514 int offset, depth;
515 int supernodeoffset = -FDT_ERR_INTERNAL;
516
517 FDT_CHECK_HEADER(fdt);
518
519 if (supernodedepth < 0)
520 return -FDT_ERR_NOTFOUND;
521
522 for (offset = 0, depth = 0;
523 (offset >= 0) && (offset <= nodeoffset);
524 offset = fdt_next_node(fdt, offset, &depth)) {
525 if (depth == supernodedepth)
526 supernodeoffset = offset;
527
528 if (offset == nodeoffset) {
529 if (nodedepth)
530 *nodedepth = depth;
531
532 if (supernodedepth > depth)
533 return -FDT_ERR_NOTFOUND;
534 else
535 return supernodeoffset;
536 }
537 }
538
539 if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
540 return -FDT_ERR_BADOFFSET;
541 else if (offset == -FDT_ERR_BADOFFSET)
542 return -FDT_ERR_BADSTRUCTURE;
543
544 return offset; /* error from fdt_next_node() */
545}
546
547int fdt_node_depth(const void *fdt, int nodeoffset)
548{
549 int nodedepth;
550 int err;
551
552 err = fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, &nodedepth);
553 if (err)
554 return (err < 0) ? err : -FDT_ERR_INTERNAL;
555 return nodedepth;
556}
557
558int fdt_parent_offset(const void *fdt, int nodeoffset)
559{
560 int nodedepth = fdt_node_depth(fdt, nodeoffset);
561
562 if (nodedepth < 0)
563 return nodedepth;
564 return fdt_supernode_atdepth_offset(fdt, nodeoffset,
565 nodedepth - 1, NULL);
566}
567
568int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
569 const char *propname,
570 const void *propval, int proplen)
571{
572 int offset;
573 const void *val;
574 int len;
575
576 FDT_CHECK_HEADER(fdt);
577
578 /* FIXME: The algorithm here is pretty horrible: we scan each
579 * property of a node in fdt_getprop(), then if that didn't
580 * find what we want, we scan over them again making our way
581 * to the next node. Still it's the easiest to implement
582 * approach; performance can come later. */
583 for (offset = fdt_next_node(fdt, startoffset, NULL);
584 offset >= 0;
585 offset = fdt_next_node(fdt, offset, NULL)) {
586 val = fdt_getprop(fdt, offset, propname, &len);
587 if (val && (len == proplen)
588 && (memcmp(val, propval, len) == 0))
589 return offset;
590 }
591
592 return offset; /* error from fdt_next_node() */
593}
594
595int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle)
596{
597 int offset;
598
599 if ((phandle == 0) || (phandle == -1))
600 return -FDT_ERR_BADPHANDLE;
601
602 FDT_CHECK_HEADER(fdt);
603
604 /* FIXME: The algorithm here is pretty horrible: we
605 * potentially scan each property of a node in
606 * fdt_get_phandle(), then if that didn't find what
607 * we want, we scan over them again making our way to the next
608 * node. Still it's the easiest to implement approach;
609 * performance can come later. */
610 for (offset = fdt_next_node(fdt, -1, NULL);
611 offset >= 0;
612 offset = fdt_next_node(fdt, offset, NULL)) {
613 if (fdt_get_phandle(fdt, offset) == phandle)
614 return offset;
615 }
616
617 return offset; /* error from fdt_next_node() */
618}
619
620int fdt_stringlist_contains(const char *strlist, int listlen, const char *str)
621{
622 int len = strlen(str);
623 const char *p;
624
625 while (listlen >= len) {
626 if (memcmp(str, strlist, len+1) == 0)
627 return 1;
628 p = memchr(strlist, '\0', listlen);
629 if (!p)
630 return 0; /* malformed strlist.. */
631 listlen -= (p-strlist) + 1;
632 strlist = p + 1;
633 }
634 return 0;
635}
636
637int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property)
638{
639 const char *list, *end;
640 int length, count = 0;
641
642 list = fdt_getprop(fdt, nodeoffset, property, &length);
643 if (!list)
644 return length;
645
646 end = list + length;
647
648 while (list < end) {
649 length = strnlen(list, end - list) + 1;
650
651 /* Abort if the last string isn't properly NUL-terminated. */
652 if (list + length > end)
653 return -FDT_ERR_BADVALUE;
654
655 list += length;
656 count++;
657 }
658
659 return count;
660}
661
662int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
663 const char *string)
664{
665 int length, len, idx = 0;
666 const char *list, *end;
667
668 list = fdt_getprop(fdt, nodeoffset, property, &length);
669 if (!list)
670 return length;
671
672 len = strlen(string) + 1;
673 end = list + length;
674
675 while (list < end) {
676 length = strnlen(list, end - list) + 1;
677
678 /* Abort if the last string isn't properly NUL-terminated. */
679 if (list + length > end)
680 return -FDT_ERR_BADVALUE;
681
682 if (length == len && memcmp(list, string, length) == 0)
683 return idx;
684
685 list += length;
686 idx++;
687 }
688
689 return -FDT_ERR_NOTFOUND;
690}
691
692const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
693 const char *property, int idx,
694 int *lenp)
695{
696 const char *list, *end;
697 int length;
698
699 list = fdt_getprop(fdt, nodeoffset, property, &length);
700 if (!list) {
701 if (lenp)
702 *lenp = length;
703
704 return NULL;
705 }
706
707 end = list + length;
708
709 while (list < end) {
710 length = strnlen(list, end - list) + 1;
711
712 /* Abort if the last string isn't properly NUL-terminated. */
713 if (list + length > end) {
714 if (lenp)
715 *lenp = -FDT_ERR_BADVALUE;
716
717 return NULL;
718 }
719
720 if (idx == 0) {
721 if (lenp)
722 *lenp = length - 1;
723
724 return list;
725 }
726
727 list += length;
728 idx--;
729 }
730
731 if (lenp)
732 *lenp = -FDT_ERR_NOTFOUND;
733
734 return NULL;
735}
736
737int fdt_node_check_compatible(const void *fdt, int nodeoffset,
738 const char *compatible)
739{
740 const void *prop;
741 int len;
742
743 prop = fdt_getprop(fdt, nodeoffset, "compatible", &len);
744 if (!prop)
745 return len;
746
747 return !fdt_stringlist_contains(prop, len, compatible);
748}
749
750int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
751 const char *compatible)
752{
753 int offset, err;
754
755 FDT_CHECK_HEADER(fdt);
756
757 /* FIXME: The algorithm here is pretty horrible: we scan each
758 * property of a node in fdt_node_check_compatible(), then if
759 * that didn't find what we want, we scan over them again
760 * making our way to the next node. Still it's the easiest to
761 * implement approach; performance can come later. */
762 for (offset = fdt_next_node(fdt, startoffset, NULL);
763 offset >= 0;
764 offset = fdt_next_node(fdt, offset, NULL)) {
765 err = fdt_node_check_compatible(fdt, offset, compatible);
766 if ((err < 0) && (err != -FDT_ERR_NOTFOUND))
767 return err;
768 else if (err == 0)
769 return offset;
770 }
771
772 return offset; /* error from fdt_next_node() */
773}