scripts/dtc/libfdt/fdt_ro.c

   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
  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
  78 const char *fdt_string(const void *fdt, int stroffset)
  79 {
  80         return (const char *)fdt + fdt_off_dt_strings(fdt) + stroffset;
  81 }
  82
  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
  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
  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
 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
 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
 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
 157 int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen)
 158 {
 159         const char *end = path + namelen;
 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 = memchr(path, '/', end - p);
 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 < end) {
 181                 const char *q;
 182
 183                 while (*p == '/') {
 184                         p++;
 185                         if (p == end)
 186                                 return offset;
 187                 }
 188                 q = memchr(p, '/', end - p);
 189                 if (! q)
 190                         q = end;
 191
 192                 offset = fdt_subnode_offset_namelen(fdt, offset, p, q-p);
 193                 if (offset < 0)
 194                         return offset;
 195
 196                 p = q;
 197         }
 198
 199         return offset;
 200 }
 201
 202 int fdt_path_offset(const void *fdt, const char *path)
 203 {
 204         return fdt_path_offset_namelen(fdt, path, strlen(path));
 205 }
 206
 207 const char *fdt_get_name(const void *fdt, int nodeoffset, int *len)
 208 {
 209         const struct fdt_node_header *nh = _fdt_offset_ptr(fdt, nodeoffset);
 210         int err;
 211
 212         if (((err = fdt_check_header(fdt)) != 0)
 213             || ((err = _fdt_check_node_offset(fdt, nodeoffset)) < 0))
 214                         goto fail;
 215
 216         if (len)
 217                 *len = strlen(nh->name);
 218
 219         return nh->name;
 220
 221  fail:
 222         if (len)
 223                 *len = err;
 224         return NULL;
 225 }
 226
 227 int fdt_first_property_offset(const void *fdt, int nodeoffset)
 228 {
 229         int offset;
 230
 231         if ((offset = _fdt_check_node_offset(fdt, nodeoffset)) < 0)
 232                 return offset;
 233
 234         return _nextprop(fdt, offset);
 235 }
 236
 237 int fdt_next_property_offset(const void *fdt, int offset)
 238 {
 239         if ((offset = _fdt_check_prop_offset(fdt, offset)) < 0)
 240                 return offset;
 241
 242         return _nextprop(fdt, offset);
 243 }
 244
 245 const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
 246                                                       int offset,
 247                                                       int *lenp)
 248 {
 249         int err;
 250         const struct fdt_property *prop;
 251
 252         if ((err = _fdt_check_prop_offset(fdt, offset)) < 0) {
 253                 if (lenp)
 254                         *lenp = err;
 255                 return NULL;
 256         }
 257
 258         prop = _fdt_offset_ptr(fdt, offset);
 259
 260         if (lenp)
 261                 *lenp = fdt32_to_cpu(prop->len);
 262
 263         return prop;
 264 }
 265
 266 const struct fdt_property *fdt_get_property_namelen(const void *fdt,
 267                                                     int offset,
 268                                                     const char *name,
 269                                                     int namelen, int *lenp)
 270 {
 271         for (offset = fdt_first_property_offset(fdt, offset);
 272              (offset >= 0);
 273              (offset = fdt_next_property_offset(fdt, offset))) {
 274                 const struct fdt_property *prop;
 275
 276                 if (!(prop = fdt_get_property_by_offset(fdt, offset, lenp))) {
 277                         offset = -FDT_ERR_INTERNAL;
 278                         break;
 279                 }
 280                 if (_fdt_string_eq(fdt, fdt32_to_cpu(prop->nameoff),
 281                                    name, namelen))
 282                         return prop;
 283         }
 284
 285         if (lenp)
 286                 *lenp = offset;
 287         return NULL;
 288 }
 289
 290 const struct fdt_property *fdt_get_property(const void *fdt,
 291                                             int nodeoffset,
 292                                             const char *name, int *lenp)
 293 {
 294         return fdt_get_property_namelen(fdt, nodeoffset, name,
 295                                         strlen(name), lenp);
 296 }
 297
 298 const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
 299                                 const char *name, int namelen, int *lenp)
 300 {
 301         const struct fdt_property *prop;
 302
 303         prop = fdt_get_property_namelen(fdt, nodeoffset, name, namelen, lenp);
 304         if (! prop)
 305                 return NULL;
 306
 307         return prop->data;
 308 }
 309
 310 const void *fdt_getprop_by_offset(const void *fdt, int offset,
 311                                   const char **namep, int *lenp)
 312 {
 313         const struct fdt_property *prop;
 314
 315         prop = fdt_get_property_by_offset(fdt, offset, lenp);
 316         if (!prop)
 317                 return NULL;
 318         if (namep)
 319                 *namep = fdt_string(fdt, fdt32_to_cpu(prop->nameoff));
 320         return prop->data;
 321 }
 322
 323 const void *fdt_getprop(const void *fdt, int nodeoffset,
 324                         const char *name, int *lenp)
 325 {
 326         return fdt_getprop_namelen(fdt, nodeoffset, name, strlen(name), lenp);
 327 }
 328
 329 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset)
 330 {
 331         const fdt32_t *php;
 332         int len;
 333
 334         /* FIXME: This is a bit sub-optimal, since we potentially scan
 335          * over all the properties twice. */
 336         php = fdt_getprop(fdt, nodeoffset, "phandle", &len);
 337         if (!php || (len != sizeof(*php))) {
 338                 php = fdt_getprop(fdt, nodeoffset, "linux,phandle", &len);
 339                 if (!php || (len != sizeof(*php)))
 340                         return 0;
 341         }
 342
 343         return fdt32_to_cpu(*php);
 344 }
 345
 346 const char *fdt_get_alias_namelen(const void *fdt,
 347                                   const char *name, int namelen)
 348 {
 349         int aliasoffset;
 350
 351         aliasoffset = fdt_path_offset(fdt, "/aliases");
 352         if (aliasoffset < 0)
 353                 return NULL;
 354
 355         return fdt_getprop_namelen(fdt, aliasoffset, name, namelen, NULL);
 356 }
 357
 358 const char *fdt_get_alias(const void *fdt, const char *name)
 359 {
 360         return fdt_get_alias_namelen(fdt, name, strlen(name));
 361 }
 362
 363 int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen)
 364 {
 365         int pdepth = 0, p = 0;
 366         int offset, depth, namelen;
 367         const char *name;
 368
 369         FDT_CHECK_HEADER(fdt);
 370
 371         if (buflen < 2)
 372                 return -FDT_ERR_NOSPACE;
 373
 374         for (offset = 0, depth = 0;
 375              (offset >= 0) && (offset <= nodeoffset);
 376              offset = fdt_next_node(fdt, offset, &depth)) {
 377                 while (pdepth > depth) {
 378                         do {
 379                                 p--;
 380                         } while (buf[p-1] != '/');
 381                         pdepth--;
 382                 }
 383
 384                 if (pdepth >= depth) {
 385                         name = fdt_get_name(fdt, offset, &namelen);
 386                         if (!name)
 387                                 return namelen;
 388                         if ((p + namelen + 1) <= buflen) {
 389                                 memcpy(buf + p, name, namelen);
 390                                 p += namelen;
 391                                 buf[p++] = '/';
 392                                 pdepth++;
 393                         }
 394                 }
 395
 396                 if (offset == nodeoffset) {
 397                         if (pdepth < (depth + 1))
 398                                 return -FDT_ERR_NOSPACE;
 399
 400                         if (p > 1) /* special case so that root path is "/", not "" */
 401                                 p--;
 402                         buf[p] = '\0';
 403                         return 0;
 404                 }
 405         }
 406
 407         if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
 408                 return -FDT_ERR_BADOFFSET;
 409         else if (offset == -FDT_ERR_BADOFFSET)
 410                 return -FDT_ERR_BADSTRUCTURE;
 411
 412         return offset; /* error from fdt_next_node() */
 413 }
 414
 415 int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
 416                                  int supernodedepth, int *nodedepth)
 417 {
 418         int offset, depth;
 419         int supernodeoffset = -FDT_ERR_INTERNAL;
 420
 421         FDT_CHECK_HEADER(fdt);
 422
 423         if (supernodedepth < 0)
 424                 return -FDT_ERR_NOTFOUND;
 425
 426         for (offset = 0, depth = 0;
 427              (offset >= 0) && (offset <= nodeoffset);
 428              offset = fdt_next_node(fdt, offset, &depth)) {
 429                 if (depth == supernodedepth)
 430                         supernodeoffset = offset;
 431
 432                 if (offset == nodeoffset) {
 433                         if (nodedepth)
 434                                 *nodedepth = depth;
 435
 436                         if (supernodedepth > depth)
 437                                 return -FDT_ERR_NOTFOUND;
 438                         else
 439                                 return supernodeoffset;
 440                 }
 441         }
 442
 443         if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
 444                 return -FDT_ERR_BADOFFSET;
 445         else if (offset == -FDT_ERR_BADOFFSET)
 446                 return -FDT_ERR_BADSTRUCTURE;
 447
 448         return offset; /* error from fdt_next_node() */
 449 }
 450
 451 int fdt_node_depth(const void *fdt, int nodeoffset)
 452 {
 453         int nodedepth;
 454         int err;
 455
 456         err = fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, &nodedepth);
 457         if (err)
 458                 return (err < 0) ? err : -FDT_ERR_INTERNAL;
 459         return nodedepth;
 460 }
 461
 462 int fdt_parent_offset(const void *fdt, int nodeoffset)
 463 {
 464         int nodedepth = fdt_node_depth(fdt, nodeoffset);
 465
 466         if (nodedepth < 0)
 467                 return nodedepth;
 468         return fdt_supernode_atdepth_offset(fdt, nodeoffset,
 469                                             nodedepth - 1, NULL);
 470 }
 471
 472 int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
 473                                   const char *propname,
 474                                   const void *propval, int proplen)
 475 {
 476         int offset;
 477         const void *val;
 478         int len;
 479
 480         FDT_CHECK_HEADER(fdt);
 481
 482         /* FIXME: The algorithm here is pretty horrible: we scan each
 483          * property of a node in fdt_getprop(), then if that didn't
 484          * find what we want, we scan over them again making our way
 485          * to the next node.  Still it's the easiest to implement
 486          * approach; performance can come later. */
 487         for (offset = fdt_next_node(fdt, startoffset, NULL);
 488              offset >= 0;
 489              offset = fdt_next_node(fdt, offset, NULL)) {
 490                 val = fdt_getprop(fdt, offset, propname, &len);
 491                 if (val && (len == proplen)
 492                     && (memcmp(val, propval, len) == 0))
 493                         return offset;
 494         }
 495
 496         return offset; /* error from fdt_next_node() */
 497 }
 498
 499 int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle)
 500 {
 501         int offset;
 502
 503         if ((phandle == 0) || (phandle == -1))
 504                 return -FDT_ERR_BADPHANDLE;
 505
 506         FDT_CHECK_HEADER(fdt);
 507
 508         /* FIXME: The algorithm here is pretty horrible: we
 509          * potentially scan each property of a node in
 510          * fdt_get_phandle(), then if that didn't find what
 511          * we want, we scan over them again making our way to the next
 512          * node.  Still it's the easiest to implement approach;
 513          * performance can come later. */
 514         for (offset = fdt_next_node(fdt, -1, NULL);
 515              offset >= 0;
 516              offset = fdt_next_node(fdt, offset, NULL)) {
 517                 if (fdt_get_phandle(fdt, offset) == phandle)
 518                         return offset;
 519         }
 520
 521         return offset; /* error from fdt_next_node() */
 522 }
 523
 524 int fdt_stringlist_contains(const char *strlist, int listlen, const char *str)
 525 {
 526         int len = strlen(str);
 527         const char *p;
 528
 529         while (listlen >= len) {
 530                 if (memcmp(str, strlist, len+1) == 0)
 531                         return 1;
 532                 p = memchr(strlist, '\0', listlen);
 533                 if (!p)
 534                         return 0; /* malformed strlist.. */
 535                 listlen -= (p-strlist) + 1;
 536                 strlist = p + 1;
 537         }
 538         return 0;
 539 }
 540
 541 int fdt_node_check_compatible(const void *fdt, int nodeoffset,
 542                               const char *compatible)
 543 {
 544         const void *prop;
 545         int len;
 546
 547         prop = fdt_getprop(fdt, nodeoffset, "compatible", &len);
 548         if (!prop)
 549                 return len;
 550         if (fdt_stringlist_contains(prop, len, compatible))
 551                 return 0;
 552         else
 553                 return 1;
 554 }
 555
 556 int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
 557                                   const char *compatible)
 558 {
 559         int offset, err;
 560
 561         FDT_CHECK_HEADER(fdt);
 562
 563         /* FIXME: The algorithm here is pretty horrible: we scan each
 564          * property of a node in fdt_node_check_compatible(), then if
 565          * that didn't find what we want, we scan over them again
 566          * making our way to the next node.  Still it's the easiest to
 567          * implement approach; performance can come later. */
 568         for (offset = fdt_next_node(fdt, startoffset, NULL);
 569              offset >= 0;
 570              offset = fdt_next_node(fdt, offset, NULL)) {
 571                 err = fdt_node_check_compatible(fdt, offset, compatible);
 572                 if ((err < 0) && (err != -FDT_ERR_NOTFOUND))
 573                         return err;
 574                 else if (err == 0)
 575                         return offset;
 576         }
 577
 578         return offset; /* error from fdt_next_node() */
 579 }