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_mem_rsv(const void * fdt,int n,uint64_t * address,uint64_t * size)91 int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size)
92 {
93 FDT_CHECK_HEADER(fdt);
94 *address = fdt64_to_cpu(_fdt_mem_rsv(fdt, n)->address);
95 *size = fdt64_to_cpu(_fdt_mem_rsv(fdt, n)->size);
96 return 0;
97 }
98
fdt_num_mem_rsv(const void * fdt)99 int fdt_num_mem_rsv(const void *fdt)
100 {
101 int i = 0;
102
103 while (fdt64_to_cpu(_fdt_mem_rsv(fdt, i)->size) != 0)
104 i++;
105 return i;
106 }
107
_nextprop(const void * fdt,int offset)108 static int _nextprop(const void *fdt, int offset)
109 {
110 uint32_t tag;
111 int nextoffset;
112
113 do {
114 tag = fdt_next_tag(fdt, offset, &nextoffset);
115
116 switch (tag) {
117 case FDT_END:
118 if (nextoffset >= 0)
119 return -FDT_ERR_BADSTRUCTURE;
120 else
121 return nextoffset;
122
123 case FDT_PROP:
124 return offset;
125 }
126 offset = nextoffset;
127 } while (tag == FDT_NOP);
128
129 return -FDT_ERR_NOTFOUND;
130 }
131
fdt_subnode_offset_namelen(const void * fdt,int offset,const char * name,int namelen)132 int fdt_subnode_offset_namelen(const void *fdt, int offset,
133 const char *name, int namelen)
134 {
135 int depth;
136
137 FDT_CHECK_HEADER(fdt);
138
139 for (depth = 0;
140 (offset >= 0) && (depth >= 0);
141 offset = fdt_next_node(fdt, offset, &depth))
142 if ((depth == 1)
143 && _fdt_nodename_eq(fdt, offset, name, namelen))
144 return offset;
145
146 if (depth < 0)
147 return -FDT_ERR_NOTFOUND;
148 return offset; /* error */
149 }
150
fdt_subnode_offset(const void * fdt,int parentoffset,const char * name)151 int fdt_subnode_offset(const void *fdt, int parentoffset,
152 const char *name)
153 {
154 return fdt_subnode_offset_namelen(fdt, parentoffset, name, strlen(name));
155 }
156
fdt_path_offset(const void * fdt,const char * path)157 int fdt_path_offset(const void *fdt, const char *path)
158 {
159 const char *end = path + strlen(path);
160 const char *p = path;
161 int offset = 0;
162
163 FDT_CHECK_HEADER(fdt);
164
165 /* see if we have an alias */
166 if (*path != '/') {
167 const char *q = strchr(path, '/');
168
169 if (!q)
170 q = end;
171
172 p = fdt_get_alias_namelen(fdt, p, q - p);
173 if (!p)
174 return -FDT_ERR_BADPATH;
175 offset = fdt_path_offset(fdt, p);
176
177 p = q;
178 }
179
180 while (*p) {
181 const char *q;
182
183 while (*p == '/')
184 p++;
185 if (! *p)
186 return offset;
187 q = strchr(p, '/');
188 if (! q)
189 q = end;
190
191 offset = fdt_subnode_offset_namelen(fdt, offset, p, q-p);
192 if (offset < 0)
193 return offset;
194
195 p = q;
196 }
197
198 return offset;
199 }
200
fdt_get_name(const void * fdt,int nodeoffset,int * len)201 const char *fdt_get_name(const void *fdt, int nodeoffset, int *len)
202 {
203 const struct fdt_node_header *nh = _fdt_offset_ptr(fdt, nodeoffset);
204 int err;
205
206 if (((err = fdt_check_header(fdt)) != 0)
207 || ((err = _fdt_check_node_offset(fdt, nodeoffset)) < 0))
208 goto fail;
209
210 if (len)
211 *len = strlen(nh->name);
212
213 return nh->name;
214
215 fail:
216 if (len)
217 *len = err;
218 return NULL;
219 }
220
fdt_first_property_offset(const void * fdt,int nodeoffset)221 int fdt_first_property_offset(const void *fdt, int nodeoffset)
222 {
223 int offset;
224
225 if ((offset = _fdt_check_node_offset(fdt, nodeoffset)) < 0)
226 return offset;
227
228 return _nextprop(fdt, offset);
229 }
230
fdt_next_property_offset(const void * fdt,int offset)231 int fdt_next_property_offset(const void *fdt, int offset)
232 {
233 if ((offset = _fdt_check_prop_offset(fdt, offset)) < 0)
234 return offset;
235
236 return _nextprop(fdt, offset);
237 }
238
fdt_get_property_by_offset(const void * fdt,int offset,int * lenp)239 const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
240 int offset,
241 int *lenp)
242 {
243 int err;
244 const struct fdt_property *prop;
245
246 if ((err = _fdt_check_prop_offset(fdt, offset)) < 0) {
247 if (lenp)
248 *lenp = err;
249 return NULL;
250 }
251
252 prop = _fdt_offset_ptr(fdt, offset);
253
254 if (lenp)
255 *lenp = fdt32_to_cpu(prop->len);
256
257 return prop;
258 }
259
fdt_get_property_namelen(const void * fdt,int offset,const char * name,int namelen,int * lenp)260 const struct fdt_property *fdt_get_property_namelen(const void *fdt,
261 int offset,
262 const char *name,
263 int namelen, int *lenp)
264 {
265 for (offset = fdt_first_property_offset(fdt, offset);
266 (offset >= 0);
267 (offset = fdt_next_property_offset(fdt, offset))) {
268 const struct fdt_property *prop;
269
270 if (!(prop = fdt_get_property_by_offset(fdt, offset, lenp))) {
271 offset = -FDT_ERR_INTERNAL;
272 break;
273 }
274 if (_fdt_string_eq(fdt, fdt32_to_cpu(prop->nameoff),
275 name, namelen))
276 return prop;
277 }
278
279 if (lenp)
280 *lenp = offset;
281 return NULL;
282 }
283
fdt_get_property(const void * fdt,int nodeoffset,const char * name,int * lenp)284 const struct fdt_property *fdt_get_property(const void *fdt,
285 int nodeoffset,
286 const char *name, int *lenp)
287 {
288 return fdt_get_property_namelen(fdt, nodeoffset, name,
289 strlen(name), lenp);
290 }
291
fdt_getprop_namelen(const void * fdt,int nodeoffset,const char * name,int namelen,int * lenp)292 const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
293 const char *name, int namelen, int *lenp)
294 {
295 const struct fdt_property *prop;
296
297 prop = fdt_get_property_namelen(fdt, nodeoffset, name, namelen, lenp);
298 if (! prop)
299 return NULL;
300
301 return prop->data;
302 }
303
fdt_getprop_by_offset(const void * fdt,int offset,const char ** namep,int * lenp)304 const void *fdt_getprop_by_offset(const void *fdt, int offset,
305 const char **namep, int *lenp)
306 {
307 const struct fdt_property *prop;
308
309 prop = fdt_get_property_by_offset(fdt, offset, lenp);
310 if (!prop)
311 return NULL;
312 if (namep)
313 *namep = fdt_string(fdt, fdt32_to_cpu(prop->nameoff));
314 return prop->data;
315 }
316
fdt_getprop(const void * fdt,int nodeoffset,const char * name,int * lenp)317 const void *fdt_getprop(const void *fdt, int nodeoffset,
318 const char *name, int *lenp)
319 {
320 return fdt_getprop_namelen(fdt, nodeoffset, name, strlen(name), lenp);
321 }
322
fdt_get_phandle(const void * fdt,int nodeoffset)323 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset)
324 {
325 const uint32_t *php;
326 int len;
327
328 /* FIXME: This is a bit sub-optimal, since we potentially scan
329 * over all the properties twice. */
330 php = fdt_getprop(fdt, nodeoffset, "phandle", &len);
331 if (!php || (len != sizeof(*php))) {
332 php = fdt_getprop(fdt, nodeoffset, "linux,phandle", &len);
333 if (!php || (len != sizeof(*php)))
334 return 0;
335 }
336
337 return fdt32_to_cpu(*php);
338 }
339
fdt_get_alias_namelen(const void * fdt,const char * name,int namelen)340 const char *fdt_get_alias_namelen(const void *fdt,
341 const char *name, int namelen)
342 {
343 int aliasoffset;
344
345 aliasoffset = fdt_path_offset(fdt, "/aliases");
346 if (aliasoffset < 0)
347 return NULL;
348
349 return fdt_getprop_namelen(fdt, aliasoffset, name, namelen, NULL);
350 }
351
fdt_get_alias(const void * fdt,const char * name)352 const char *fdt_get_alias(const void *fdt, const char *name)
353 {
354 return fdt_get_alias_namelen(fdt, name, strlen(name));
355 }
356
fdt_get_path(const void * fdt,int nodeoffset,char * buf,int buflen)357 int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen)
358 {
359 int pdepth = 0, p = 0;
360 int offset, depth, namelen;
361 const char *name;
362
363 FDT_CHECK_HEADER(fdt);
364
365 if (buflen < 2)
366 return -FDT_ERR_NOSPACE;
367
368 for (offset = 0, depth = 0;
369 (offset >= 0) && (offset <= nodeoffset);
370 offset = fdt_next_node(fdt, offset, &depth)) {
371 while (pdepth > depth) {
372 do {
373 p--;
374 } while (buf[p-1] != '/');
375 pdepth--;
376 }
377
378 if (pdepth >= depth) {
379 name = fdt_get_name(fdt, offset, &namelen);
380 if (!name)
381 return namelen;
382 if ((p + namelen + 1) <= buflen) {
383 memcpy(buf + p, name, namelen);
384 p += namelen;
385 buf[p++] = '/';
386 pdepth++;
387 }
388 }
389
390 if (offset == nodeoffset) {
391 if (pdepth < (depth + 1))
392 return -FDT_ERR_NOSPACE;
393
394 if (p > 1) /* special case so that root path is "/", not "" */
395 p--;
396 buf[p] = '\0';
397 return 0;
398 }
399 }
400
401 if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
402 return -FDT_ERR_BADOFFSET;
403 else if (offset == -FDT_ERR_BADOFFSET)
404 return -FDT_ERR_BADSTRUCTURE;
405
406 return offset; /* error from fdt_next_node() */
407 }
408
fdt_supernode_atdepth_offset(const void * fdt,int nodeoffset,int supernodedepth,int * nodedepth)409 int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
410 int supernodedepth, int *nodedepth)
411 {
412 int offset, depth;
413 int supernodeoffset = -FDT_ERR_INTERNAL;
414
415 FDT_CHECK_HEADER(fdt);
416
417 if (supernodedepth < 0)
418 return -FDT_ERR_NOTFOUND;
419
420 for (offset = 0, depth = 0;
421 (offset >= 0) && (offset <= nodeoffset);
422 offset = fdt_next_node(fdt, offset, &depth)) {
423 if (depth == supernodedepth)
424 supernodeoffset = offset;
425
426 if (offset == nodeoffset) {
427 if (nodedepth)
428 *nodedepth = depth;
429
430 if (supernodedepth > depth)
431 return -FDT_ERR_NOTFOUND;
432 else
433 return supernodeoffset;
434 }
435 }
436
437 if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
438 return -FDT_ERR_BADOFFSET;
439 else if (offset == -FDT_ERR_BADOFFSET)
440 return -FDT_ERR_BADSTRUCTURE;
441
442 return offset; /* error from fdt_next_node() */
443 }
444
fdt_node_depth(const void * fdt,int nodeoffset)445 int fdt_node_depth(const void *fdt, int nodeoffset)
446 {
447 int nodedepth;
448 int err;
449
450 err = fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, &nodedepth);
451 if (err)
452 return (err < 0) ? err : -FDT_ERR_INTERNAL;
453 return nodedepth;
454 }
455
fdt_parent_offset(const void * fdt,int nodeoffset)456 int fdt_parent_offset(const void *fdt, int nodeoffset)
457 {
458 int nodedepth = fdt_node_depth(fdt, nodeoffset);
459
460 if (nodedepth < 0)
461 return nodedepth;
462 return fdt_supernode_atdepth_offset(fdt, nodeoffset,
463 nodedepth - 1, NULL);
464 }
465
fdt_node_offset_by_prop_value(const void * fdt,int startoffset,const char * propname,const void * propval,int proplen)466 int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
467 const char *propname,
468 const void *propval, int proplen)
469 {
470 int offset;
471 const void *val;
472 int len;
473
474 FDT_CHECK_HEADER(fdt);
475
476 /* FIXME: The algorithm here is pretty horrible: we scan each
477 * property of a node in fdt_getprop(), then if that didn't
478 * find what we want, we scan over them again making our way
479 * to the next node. Still it's the easiest to implement
480 * approach; performance can come later. */
481 for (offset = fdt_next_node(fdt, startoffset, NULL);
482 offset >= 0;
483 offset = fdt_next_node(fdt, offset, NULL)) {
484 val = fdt_getprop(fdt, offset, propname, &len);
485 if (val && (len == proplen)
486 && (memcmp(val, propval, len) == 0))
487 return offset;
488 }
489
490 return offset; /* error from fdt_next_node() */
491 }
492
fdt_node_offset_by_phandle(const void * fdt,uint32_t phandle)493 int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle)
494 {
495 int offset;
496
497 if ((phandle == 0) || (phandle == -1))
498 return -FDT_ERR_BADPHANDLE;
499
500 FDT_CHECK_HEADER(fdt);
501
502 /* FIXME: The algorithm here is pretty horrible: we
503 * potentially scan each property of a node in
504 * fdt_get_phandle(), then if that didn't find what
505 * we want, we scan over them again making our way to the next
506 * node. Still it's the easiest to implement approach;
507 * performance can come later. */
508 for (offset = fdt_next_node(fdt, -1, NULL);
509 offset >= 0;
510 offset = fdt_next_node(fdt, offset, NULL)) {
511 if (fdt_get_phandle(fdt, offset) == phandle)
512 return offset;
513 }
514
515 return offset; /* error from fdt_next_node() */
516 }
517
_fdt_stringlist_contains(const char * strlist,int listlen,const char * str)518 static int _fdt_stringlist_contains(const char *strlist, int listlen,
519 const char *str)
520 {
521 int len = strlen(str);
522 const char *p;
523
524 while (listlen >= len) {
525 if (memcmp(str, strlist, len+1) == 0)
526 return 1;
527 p = memchr(strlist, '\0', listlen);
528 if (!p)
529 return 0; /* malformed strlist.. */
530 listlen -= (p-strlist) + 1;
531 strlist = p + 1;
532 }
533 return 0;
534 }
535
fdt_node_check_compatible(const void * fdt,int nodeoffset,const char * compatible)536 int fdt_node_check_compatible(const void *fdt, int nodeoffset,
537 const char *compatible)
538 {
539 const void *prop;
540 int len;
541
542 prop = fdt_getprop(fdt, nodeoffset, "compatible", &len);
543 if (!prop)
544 return len;
545 if (_fdt_stringlist_contains(prop, len, compatible))
546 return 0;
547 else
548 return 1;
549 }
550
fdt_node_offset_by_compatible(const void * fdt,int startoffset,const char * compatible)551 int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
552 const char *compatible)
553 {
554 int offset, err;
555
556 FDT_CHECK_HEADER(fdt);
557
558 /* FIXME: The algorithm here is pretty horrible: we scan each
559 * property of a node in fdt_node_check_compatible(), then if
560 * that didn't find what we want, we scan over them again
561 * making our way to the next node. Still it's the easiest to
562 * implement approach; performance can come later. */
563 for (offset = fdt_next_node(fdt, startoffset, NULL);
564 offset >= 0;
565 offset = fdt_next_node(fdt, offset, NULL)) {
566 err = fdt_node_check_compatible(fdt, offset, compatible);
567 if ((err < 0) && (err != -FDT_ERR_NOTFOUND))
568 return err;
569 else if (err == 0)
570 return offset;
571 }
572
573 return offset; /* error from fdt_next_node() */
574 }
575