EmbeddedPkg/Library/FdtLib/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(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
 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
 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
 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
 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
 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                 prop = fdt_get_property_by_offset(fdt, offset, lenp);
 271                 if (!prop) {
 272                         offset = -FDT_ERR_INTERNAL;
 273                         break;
 274                 }
 275                 if (_fdt_string_eq(fdt, fdt32_to_cpu(prop->nameoff),
 276                                    name, namelen))
 277                         return prop;
 278         }
 279
 280         if (lenp)
 281                 *lenp = offset;
 282         return NULL;
 283 }
 284
 285 const struct fdt_property *fdt_get_property(const void *fdt,
 286                                             int nodeoffset,
 287                                             const char *name, int *lenp)
 288 {
 289         return fdt_get_property_namelen(fdt, nodeoffset, name,
 290                                         strlen(name), lenp);
 291 }
 292
 293 const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
 294                                 const char *name, int namelen, int *lenp)
 295 {
 296         const struct fdt_property *prop;
 297
 298         prop = fdt_get_property_namelen(fdt, nodeoffset, name, namelen, lenp);
 299         if (! prop)
 300                 return NULL;
 301
 302         return prop->data;
 303 }
 304
 305 const void *fdt_getprop_by_offset(const void *fdt, int offset,
 306                                   const char **namep, int *lenp)
 307 {
 308         const struct fdt_property *prop;
 309
 310         prop = fdt_get_property_by_offset(fdt, offset, lenp);
 311         if (!prop)
 312                 return NULL;
 313         if (namep)
 314                 *namep = fdt_string(fdt, fdt32_to_cpu(prop->nameoff));
 315         return prop->data;
 316 }
 317
 318 const void *fdt_getprop(const void *fdt, int nodeoffset,
 319                         const char *name, int *lenp)
 320 {
 321         return fdt_getprop_namelen(fdt, nodeoffset, name, strlen(name), lenp);
 322 }
 323
 324 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset)
 325 {
 326         const fdt32_t *php;
 327         int len;
 328
 329         /* FIXME: This is a bit sub-optimal, since we potentially scan
 330          * over all the properties twice. */
 331         php = fdt_getprop(fdt, nodeoffset, "phandle", &len);
 332         if (!php || (len != sizeof(*php))) {
 333                 php = fdt_getprop(fdt, nodeoffset, "linux,phandle", &len);
 334                 if (!php || (len != sizeof(*php)))
 335                         return 0;
 336         }
 337
 338         return fdt32_to_cpu(*php);
 339 }
 340
 341 const char *fdt_get_alias_namelen(const void *fdt,
 342                                   const char *name, int namelen)
 343 {
 344         int aliasoffset;
 345
 346         aliasoffset = fdt_path_offset(fdt, "/aliases");
 347         if (aliasoffset < 0)
 348                 return NULL;
 349
 350         return fdt_getprop_namelen(fdt, aliasoffset, name, namelen, NULL);
 351 }
 352
 353 const char *fdt_get_alias(const void *fdt, const char *name)
 354 {
 355         return fdt_get_alias_namelen(fdt, name, strlen(name));
 356 }
 357
 358 int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen)
 359 {
 360         int pdepth = 0, p = 0;
 361         int offset, depth, namelen;
 362         const char *name;
 363
 364         FDT_CHECK_HEADER(fdt);
 365
 366         if (buflen < 2)
 367                 return -FDT_ERR_NOSPACE;
 368
 369         for (offset = 0, depth = 0;
 370              (offset >= 0) && (offset <= nodeoffset);
 371              offset = fdt_next_node(fdt, offset, &depth)) {
 372                 while (pdepth > depth) {
 373                         do {
 374                                 p--;
 375                         } while (buf[p-1] != '/');
 376                         pdepth--;
 377                 }
 378
 379                 if (pdepth >= depth) {
 380                         name = fdt_get_name(fdt, offset, &namelen);
 381                         if (!name)
 382                                 return namelen;
 383                         if ((p + namelen + 1) <= buflen) {
 384                                 memcpy(buf + p, name, namelen);
 385                                 p += namelen;
 386                                 buf[p++] = '/';
 387                                 pdepth++;
 388                         }
 389                 }
 390
 391                 if (offset == nodeoffset) {
 392                         if (pdepth < (depth + 1))
 393                                 return -FDT_ERR_NOSPACE;
 394
 395                         if (p > 1) /* special case so that root path is "/", not "" */
 396                                 p--;
 397                         buf[p] = '\0';
 398                         return 0;
 399                 }
 400         }
 401
 402         if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
 403                 return -FDT_ERR_BADOFFSET;
 404         else if (offset == -FDT_ERR_BADOFFSET)
 405                 return -FDT_ERR_BADSTRUCTURE;
 406
 407         return offset; /* error from fdt_next_node() */
 408 }
 409
 410 int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
 411                                  int supernodedepth, int *nodedepth)
 412 {
 413         int offset, depth;
 414         int supernodeoffset = -FDT_ERR_INTERNAL;
 415
 416         FDT_CHECK_HEADER(fdt);
 417
 418         if (supernodedepth < 0)
 419                 return -FDT_ERR_NOTFOUND;
 420
 421         for (offset = 0, depth = 0;
 422              (offset >= 0) && (offset <= nodeoffset);
 423              offset = fdt_next_node(fdt, offset, &depth)) {
 424                 if (depth == supernodedepth)
 425                         supernodeoffset = offset;
 426
 427                 if (offset == nodeoffset) {
 428                         if (nodedepth)
 429                                 *nodedepth = depth;
 430
 431                         if (supernodedepth > depth)
 432                                 return -FDT_ERR_NOTFOUND;
 433                         else
 434                                 return supernodeoffset;
 435                 }
 436         }
 437
 438         if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
 439                 return -FDT_ERR_BADOFFSET;
 440         else if (offset == -FDT_ERR_BADOFFSET)
 441                 return -FDT_ERR_BADSTRUCTURE;
 442
 443         return offset; /* error from fdt_next_node() */
 444 }
 445
 446 int fdt_node_depth(const void *fdt, int nodeoffset)
 447 {
 448         int nodedepth;
 449         int err;
 450
 451         err = fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, &nodedepth);
 452         if (err)
 453                 return (err < 0) ? err : -FDT_ERR_INTERNAL;
 454         return nodedepth;
 455 }
 456
 457 int fdt_parent_offset(const void *fdt, int nodeoffset)
 458 {
 459         int nodedepth = fdt_node_depth(fdt, nodeoffset);
 460
 461         if (nodedepth < 0)
 462                 return nodedepth;
 463         return fdt_supernode_atdepth_offset(fdt, nodeoffset,
 464                                             nodedepth - 1, NULL);
 465 }
 466
 467 int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
 468                                   const char *propname,
 469                                   const void *propval, int proplen)
 470 {
 471         int offset;
 472         const void *val;
 473         int len;
 474
 475         FDT_CHECK_HEADER(fdt);
 476
 477         /* FIXME: The algorithm here is pretty horrible: we scan each
 478          * property of a node in fdt_getprop(), then if that didn't
 479          * find what we want, we scan over them again making our way
 480          * to the next node.  Still it's the easiest to implement
 481          * approach; performance can come later. */
 482         for (offset = fdt_next_node(fdt, startoffset, NULL);
 483              offset >= 0;
 484              offset = fdt_next_node(fdt, offset, NULL)) {
 485                 val = fdt_getprop(fdt, offset, propname, &len);
 486                 if (val && (len == proplen)
 487                     && (memcmp(val, propval, len) == 0))
 488                         return offset;
 489         }
 490
 491         return offset; /* error from fdt_next_node() */
 492 }
 493
 494 int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle)
 495 {
 496         int offset;
 497
 498         if ((phandle == 0) || (phandle == (uint32_t)-1))
 499                 return -FDT_ERR_BADPHANDLE;
 500
 501         FDT_CHECK_HEADER(fdt);
 502
 503         /* FIXME: The algorithm here is pretty horrible: we
 504          * potentially scan each property of a node in
 505          * fdt_get_phandle(), then if that didn't find what
 506          * we want, we scan over them again making our way to the next
 507          * node.  Still it's the easiest to implement approach;
 508          * performance can come later. */
 509         for (offset = fdt_next_node(fdt, -1, NULL);
 510              offset >= 0;
 511              offset = fdt_next_node(fdt, offset, NULL)) {
 512                 if (fdt_get_phandle(fdt, offset) == phandle)
 513                         return offset;
 514         }
 515
 516         return offset; /* error from fdt_next_node() */
 517 }
 518
 519 int fdt_stringlist_contains(const char *strlist, int listlen, 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
 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
 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 }