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
_fdt_nodename_eq(const void * fdt,int offset,const char * s,int len)58 static int _fdt_nodename_eq(const void *fdt, int offset,
59 const char *s, int len)
60 {
61 const char *p = fdt_offset_ptr(fdt, offset + FDT_TAGSIZE, len+1);
62
63 if (! p)
64 /* short match */
65 return 0;
66
67 if (memcmp(p, s, len) != 0)
68 return 0;
69
70 if (p[len] == '\0')
71 return 1;
72 else if (!memchr(s, '@', len) && (p[len] == '@'))
73 return 1;
74 else
75 return 0;
76 }
77
fdt_string(const void * fdt,int stroffset)78 const char *fdt_string(const void *fdt, int stroffset)
79 {
80 return (const char *)fdt + fdt_off_dt_strings(fdt) + stroffset;
81 }
82
_fdt_string_eq(const void * fdt,int stroffset,const char * s,int len)83 static int _fdt_string_eq(const void *fdt, int stroffset,
84 const char *s, int len)
85 {
86 const char *p = fdt_string(fdt, stroffset);
87
88 return (strlen(p) == len) && (memcmp(p, s, len) == 0);
89 }
90
fdt_get_max_phandle(const void * fdt)91 uint32_t fdt_get_max_phandle(const void *fdt)
92 {
93 uint32_t max_phandle = 0;
94 int offset;
95
96 for (offset = fdt_next_node(fdt, -1, NULL);;
97 offset = fdt_next_node(fdt, offset, NULL)) {
98 uint32_t phandle;
99
100 if (offset == -FDT_ERR_NOTFOUND)
101 return max_phandle;
102
103 if (offset < 0)
104 return (uint32_t)-1;
105
106 phandle = fdt_get_phandle(fdt, offset);
107 if (phandle == (uint32_t)-1)
108 continue;
109
110 if (phandle > max_phandle)
111 max_phandle = phandle;
112 }
113
114 return 0;
115 }
116
fdt_get_mem_rsv(const void * fdt,int n,uint64_t * address,uint64_t * size)117 int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size)
118 {
119 FDT_CHECK_HEADER(fdt);
120 *address = fdt64_to_cpu(_fdt_mem_rsv(fdt, n)->address);
121 *size = fdt64_to_cpu(_fdt_mem_rsv(fdt, n)->size);
122 return 0;
123 }
124
fdt_num_mem_rsv(const void * fdt)125 int fdt_num_mem_rsv(const void *fdt)
126 {
127 int i = 0;
128
129 while (fdt64_to_cpu(_fdt_mem_rsv(fdt, i)->size) != 0)
130 i++;
131 return i;
132 }
133
_nextprop(const void * fdt,int offset)134 static int _nextprop(const void *fdt, int offset)
135 {
136 uint32_t tag;
137 int nextoffset;
138
139 do {
140 tag = fdt_next_tag(fdt, offset, &nextoffset);
141
142 switch (tag) {
143 case FDT_END:
144 if (nextoffset >= 0)
145 return -FDT_ERR_BADSTRUCTURE;
146 else
147 return nextoffset;
148
149 case FDT_PROP:
150 return offset;
151 }
152 offset = nextoffset;
153 } while (tag == FDT_NOP);
154
155 return -FDT_ERR_NOTFOUND;
156 }
157
fdt_subnode_offset_namelen(const void * fdt,int offset,const char * name,int namelen)158 int fdt_subnode_offset_namelen(const void *fdt, int offset,
159 const char *name, int namelen)
160 {
161 int depth;
162
163 FDT_CHECK_HEADER(fdt);
164
165 for (depth = 0;
166 (offset >= 0) && (depth >= 0);
167 offset = fdt_next_node(fdt, offset, &depth))
168 if ((depth == 1)
169 && _fdt_nodename_eq(fdt, offset, name, namelen))
170 return offset;
171
172 if (depth < 0)
173 return -FDT_ERR_NOTFOUND;
174 return offset; /* error */
175 }
176
fdt_subnode_offset(const void * fdt,int parentoffset,const char * name)177 int fdt_subnode_offset(const void *fdt, int parentoffset,
178 const char *name)
179 {
180 return fdt_subnode_offset_namelen(fdt, parentoffset, name, strlen(name));
181 }
182
fdt_path_offset_namelen(const void * fdt,const char * path,int namelen)183 int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen)
184 {
185 const char *end = path + namelen;
186 const char *p = path;
187 int offset = 0;
188
189 FDT_CHECK_HEADER(fdt);
190
191 /* see if we have an alias */
192 if (*path != '/') {
193 const char *q = memchr(path, '/', end - p);
194
195 if (!q)
196 q = end;
197
198 p = fdt_get_alias_namelen(fdt, p, q - p);
199 if (!p)
200 return -FDT_ERR_BADPATH;
201 offset = fdt_path_offset(fdt, p);
202
203 p = q;
204 }
205
206 while (p < end) {
207 const char *q;
208
209 while (*p == '/') {
210 p++;
211 if (p == end)
212 return offset;
213 }
214 q = memchr(p, '/', end - p);
215 if (! q)
216 q = end;
217
218 offset = fdt_subnode_offset_namelen(fdt, offset, p, q-p);
219 if (offset < 0)
220 return offset;
221
222 p = q;
223 }
224
225 return offset;
226 }
227
fdt_path_offset(const void * fdt,const char * path)228 int fdt_path_offset(const void *fdt, const char *path)
229 {
230 return fdt_path_offset_namelen(fdt, path, strlen(path));
231 }
232
fdt_get_name(const void * fdt,int nodeoffset,int * len)233 const char *fdt_get_name(const void *fdt, int nodeoffset, int *len)
234 {
235 const struct fdt_node_header *nh = _fdt_offset_ptr(fdt, nodeoffset);
236 int err;
237
238 if (((err = fdt_check_header(fdt)) != 0)
239 || ((err = _fdt_check_node_offset(fdt, nodeoffset)) < 0))
240 goto fail;
241
242 if (len)
243 *len = strlen(nh->name);
244
245 return nh->name;
246
247 fail:
248 if (len)
249 *len = err;
250 return NULL;
251 }
252
fdt_first_property_offset(const void * fdt,int nodeoffset)253 int fdt_first_property_offset(const void *fdt, int nodeoffset)
254 {
255 int offset;
256
257 if ((offset = _fdt_check_node_offset(fdt, nodeoffset)) < 0)
258 return offset;
259
260 return _nextprop(fdt, offset);
261 }
262
fdt_next_property_offset(const void * fdt,int offset)263 int fdt_next_property_offset(const void *fdt, int offset)
264 {
265 if ((offset = _fdt_check_prop_offset(fdt, offset)) < 0)
266 return offset;
267
268 return _nextprop(fdt, offset);
269 }
270
fdt_get_property_by_offset(const void * fdt,int offset,int * lenp)271 const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
272 int offset,
273 int *lenp)
274 {
275 int err;
276 const struct fdt_property *prop;
277
278 if ((err = _fdt_check_prop_offset(fdt, offset)) < 0) {
279 if (lenp)
280 *lenp = err;
281 return NULL;
282 }
283
284 prop = _fdt_offset_ptr(fdt, offset);
285
286 if (lenp)
287 *lenp = fdt32_to_cpu(prop->len);
288
289 return prop;
290 }
291
fdt_get_property_namelen(const void * fdt,int offset,const char * name,int namelen,int * lenp)292 const struct fdt_property *fdt_get_property_namelen(const void *fdt,
293 int offset,
294 const char *name,
295 int namelen, int *lenp)
296 {
297 for (offset = fdt_first_property_offset(fdt, offset);
298 (offset >= 0);
299 (offset = fdt_next_property_offset(fdt, offset))) {
300 const struct fdt_property *prop;
301
302 if (!(prop = fdt_get_property_by_offset(fdt, offset, lenp))) {
303 offset = -FDT_ERR_INTERNAL;
304 break;
305 }
306 if (_fdt_string_eq(fdt, fdt32_to_cpu(prop->nameoff),
307 name, namelen))
308 return prop;
309 }
310
311 if (lenp)
312 *lenp = offset;
313 return NULL;
314 }
315
fdt_get_property(const void * fdt,int nodeoffset,const char * name,int * lenp)316 const struct fdt_property *fdt_get_property(const void *fdt,
317 int nodeoffset,
318 const char *name, int *lenp)
319 {
320 return fdt_get_property_namelen(fdt, nodeoffset, name,
321 strlen(name), lenp);
322 }
323
fdt_getprop_namelen(const void * fdt,int nodeoffset,const char * name,int namelen,int * lenp)324 const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
325 const char *name, int namelen, int *lenp)
326 {
327 const struct fdt_property *prop;
328
329 prop = fdt_get_property_namelen(fdt, nodeoffset, name, namelen, lenp);
330 if (! prop)
331 return NULL;
332
333 return prop->data;
334 }
335
fdt_getprop_by_offset(const void * fdt,int offset,const char ** namep,int * lenp)336 const void *fdt_getprop_by_offset(const void *fdt, int offset,
337 const char **namep, int *lenp)
338 {
339 const struct fdt_property *prop;
340
341 prop = fdt_get_property_by_offset(fdt, offset, lenp);
342 if (!prop)
343 return NULL;
344 if (namep)
345 *namep = fdt_string(fdt, fdt32_to_cpu(prop->nameoff));
346 return prop->data;
347 }
348
fdt_getprop(const void * fdt,int nodeoffset,const char * name,int * lenp)349 const void *fdt_getprop(const void *fdt, int nodeoffset,
350 const char *name, int *lenp)
351 {
352 return fdt_getprop_namelen(fdt, nodeoffset, name, strlen(name), lenp);
353 }
354
fdt_get_phandle(const void * fdt,int nodeoffset)355 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset)
356 {
357 const fdt32_t *php;
358 int len;
359
360 /* FIXME: This is a bit sub-optimal, since we potentially scan
361 * over all the properties twice. */
362 php = fdt_getprop(fdt, nodeoffset, "phandle", &len);
363 if (!php || (len != sizeof(*php))) {
364 php = fdt_getprop(fdt, nodeoffset, "linux,phandle", &len);
365 if (!php || (len != sizeof(*php)))
366 return 0;
367 }
368
369 return fdt32_to_cpu(*php);
370 }
371
fdt_get_alias_namelen(const void * fdt,const char * name,int namelen)372 const char *fdt_get_alias_namelen(const void *fdt,
373 const char *name, int namelen)
374 {
375 int aliasoffset;
376
377 aliasoffset = fdt_path_offset(fdt, "/aliases");
378 if (aliasoffset < 0)
379 return NULL;
380
381 return fdt_getprop_namelen(fdt, aliasoffset, name, namelen, NULL);
382 }
383
fdt_get_alias(const void * fdt,const char * name)384 const char *fdt_get_alias(const void *fdt, const char *name)
385 {
386 return fdt_get_alias_namelen(fdt, name, strlen(name));
387 }
388
fdt_get_path(const void * fdt,int nodeoffset,char * buf,int buflen)389 int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen)
390 {
391 int pdepth = 0, p = 0;
392 int offset, depth, namelen;
393 const char *name;
394
395 FDT_CHECK_HEADER(fdt);
396
397 if (buflen < 2)
398 return -FDT_ERR_NOSPACE;
399
400 for (offset = 0, depth = 0;
401 (offset >= 0) && (offset <= nodeoffset);
402 offset = fdt_next_node(fdt, offset, &depth)) {
403 while (pdepth > depth) {
404 do {
405 p--;
406 } while (buf[p-1] != '/');
407 pdepth--;
408 }
409
410 if (pdepth >= depth) {
411 name = fdt_get_name(fdt, offset, &namelen);
412 if (!name)
413 return namelen;
414 if ((p + namelen + 1) <= buflen) {
415 memcpy(buf + p, name, namelen);
416 p += namelen;
417 buf[p++] = '/';
418 pdepth++;
419 }
420 }
421
422 if (offset == nodeoffset) {
423 if (pdepth < (depth + 1))
424 return -FDT_ERR_NOSPACE;
425
426 if (p > 1) /* special case so that root path is "/", not "" */
427 p--;
428 buf[p] = '\0';
429 return 0;
430 }
431 }
432
433 if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
434 return -FDT_ERR_BADOFFSET;
435 else if (offset == -FDT_ERR_BADOFFSET)
436 return -FDT_ERR_BADSTRUCTURE;
437
438 return offset; /* error from fdt_next_node() */
439 }
440
fdt_supernode_atdepth_offset(const void * fdt,int nodeoffset,int supernodedepth,int * nodedepth)441 int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
442 int supernodedepth, int *nodedepth)
443 {
444 int offset, depth;
445 int supernodeoffset = -FDT_ERR_INTERNAL;
446
447 FDT_CHECK_HEADER(fdt);
448
449 if (supernodedepth < 0)
450 return -FDT_ERR_NOTFOUND;
451
452 for (offset = 0, depth = 0;
453 (offset >= 0) && (offset <= nodeoffset);
454 offset = fdt_next_node(fdt, offset, &depth)) {
455 if (depth == supernodedepth)
456 supernodeoffset = offset;
457
458 if (offset == nodeoffset) {
459 if (nodedepth)
460 *nodedepth = depth;
461
462 if (supernodedepth > depth)
463 return -FDT_ERR_NOTFOUND;
464 else
465 return supernodeoffset;
466 }
467 }
468
469 if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
470 return -FDT_ERR_BADOFFSET;
471 else if (offset == -FDT_ERR_BADOFFSET)
472 return -FDT_ERR_BADSTRUCTURE;
473
474 return offset; /* error from fdt_next_node() */
475 }
476
fdt_node_depth(const void * fdt,int nodeoffset)477 int fdt_node_depth(const void *fdt, int nodeoffset)
478 {
479 int nodedepth;
480 int err;
481
482 err = fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, &nodedepth);
483 if (err)
484 return (err < 0) ? err : -FDT_ERR_INTERNAL;
485 return nodedepth;
486 }
487
fdt_parent_offset(const void * fdt,int nodeoffset)488 int fdt_parent_offset(const void *fdt, int nodeoffset)
489 {
490 int nodedepth = fdt_node_depth(fdt, nodeoffset);
491
492 if (nodedepth < 0)
493 return nodedepth;
494 return fdt_supernode_atdepth_offset(fdt, nodeoffset,
495 nodedepth - 1, NULL);
496 }
497
fdt_node_offset_by_prop_value(const void * fdt,int startoffset,const char * propname,const void * propval,int proplen)498 int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
499 const char *propname,
500 const void *propval, int proplen)
501 {
502 int offset;
503 const void *val;
504 int len;
505
506 FDT_CHECK_HEADER(fdt);
507
508 /* FIXME: The algorithm here is pretty horrible: we scan each
509 * property of a node in fdt_getprop(), then if that didn't
510 * find what we want, we scan over them again making our way
511 * to the next node. Still it's the easiest to implement
512 * approach; performance can come later. */
513 for (offset = fdt_next_node(fdt, startoffset, NULL);
514 offset >= 0;
515 offset = fdt_next_node(fdt, offset, NULL)) {
516 val = fdt_getprop(fdt, offset, propname, &len);
517 if (val && (len == proplen)
518 && (memcmp(val, propval, len) == 0))
519 return offset;
520 }
521
522 return offset; /* error from fdt_next_node() */
523 }
524
fdt_node_offset_by_phandle(const void * fdt,uint32_t phandle)525 int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle)
526 {
527 int offset;
528
529 if ((phandle == 0) || (phandle == -1))
530 return -FDT_ERR_BADPHANDLE;
531
532 FDT_CHECK_HEADER(fdt);
533
534 /* FIXME: The algorithm here is pretty horrible: we
535 * potentially scan each property of a node in
536 * fdt_get_phandle(), then if that didn't find what
537 * we want, we scan over them again making our way to the next
538 * node. Still it's the easiest to implement approach;
539 * performance can come later. */
540 for (offset = fdt_next_node(fdt, -1, NULL);
541 offset >= 0;
542 offset = fdt_next_node(fdt, offset, NULL)) {
543 if (fdt_get_phandle(fdt, offset) == phandle)
544 return offset;
545 }
546
547 return offset; /* error from fdt_next_node() */
548 }
549
fdt_stringlist_contains(const char * strlist,int listlen,const char * str)550 int fdt_stringlist_contains(const char *strlist, int listlen, const char *str)
551 {
552 int len = strlen(str);
553 const char *p;
554
555 while (listlen >= len) {
556 if (memcmp(str, strlist, len+1) == 0)
557 return 1;
558 p = memchr(strlist, '\0', listlen);
559 if (!p)
560 return 0; /* malformed strlist.. */
561 listlen -= (p-strlist) + 1;
562 strlist = p + 1;
563 }
564 return 0;
565 }
566
fdt_stringlist_count(const void * fdt,int nodeoffset,const char * property)567 int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property)
568 {
569 const char *list, *end;
570 int length, count = 0;
571
572 list = fdt_getprop(fdt, nodeoffset, property, &length);
573 if (!list)
574 return -length;
575
576 end = list + length;
577
578 while (list < end) {
579 length = strnlen(list, end - list) + 1;
580
581 /* Abort if the last string isn't properly NUL-terminated. */
582 if (list + length > end)
583 return -FDT_ERR_BADVALUE;
584
585 list += length;
586 count++;
587 }
588
589 return count;
590 }
591
fdt_stringlist_search(const void * fdt,int nodeoffset,const char * property,const char * string)592 int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
593 const char *string)
594 {
595 int length, len, idx = 0;
596 const char *list, *end;
597
598 list = fdt_getprop(fdt, nodeoffset, property, &length);
599 if (!list)
600 return -length;
601
602 len = strlen(string) + 1;
603 end = list + length;
604
605 while (list < end) {
606 length = strnlen(list, end - list) + 1;
607
608 /* Abort if the last string isn't properly NUL-terminated. */
609 if (list + length > end)
610 return -FDT_ERR_BADVALUE;
611
612 if (length == len && memcmp(list, string, length) == 0)
613 return idx;
614
615 list += length;
616 idx++;
617 }
618
619 return -FDT_ERR_NOTFOUND;
620 }
621
fdt_stringlist_get(const void * fdt,int nodeoffset,const char * property,int idx,int * lenp)622 const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
623 const char *property, int idx,
624 int *lenp)
625 {
626 const char *list, *end;
627 int length;
628
629 list = fdt_getprop(fdt, nodeoffset, property, &length);
630 if (!list) {
631 if (lenp)
632 *lenp = length;
633
634 return NULL;
635 }
636
637 end = list + length;
638
639 while (list < end) {
640 length = strnlen(list, end - list) + 1;
641
642 /* Abort if the last string isn't properly NUL-terminated. */
643 if (list + length > end) {
644 if (lenp)
645 *lenp = -FDT_ERR_BADVALUE;
646
647 return NULL;
648 }
649
650 if (idx == 0) {
651 if (lenp)
652 *lenp = length - 1;
653
654 return list;
655 }
656
657 list += length;
658 idx--;
659 }
660
661 if (lenp)
662 *lenp = -FDT_ERR_NOTFOUND;
663
664 return NULL;
665 }
666
fdt_node_check_compatible(const void * fdt,int nodeoffset,const char * compatible)667 int fdt_node_check_compatible(const void *fdt, int nodeoffset,
668 const char *compatible)
669 {
670 const void *prop;
671 int len;
672
673 prop = fdt_getprop(fdt, nodeoffset, "compatible", &len);
674 if (!prop)
675 return len;
676
677 return !fdt_stringlist_contains(prop, len, compatible);
678 }
679
fdt_node_offset_by_compatible(const void * fdt,int startoffset,const char * compatible)680 int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
681 const char *compatible)
682 {
683 int offset, err;
684
685 FDT_CHECK_HEADER(fdt);
686
687 /* FIXME: The algorithm here is pretty horrible: we scan each
688 * property of a node in fdt_node_check_compatible(), then if
689 * that didn't find what we want, we scan over them again
690 * making our way to the next node. Still it's the easiest to
691 * implement approach; performance can come later. */
692 for (offset = fdt_next_node(fdt, startoffset, NULL);
693 offset >= 0;
694 offset = fdt_next_node(fdt, offset, NULL)) {
695 err = fdt_node_check_compatible(fdt, offset, compatible);
696 if ((err < 0) && (err != -FDT_ERR_NOTFOUND))
697 return err;
698 else if (err == 0)
699 return offset;
700 }
701
702 return offset; /* error from fdt_next_node() */
703 }
704