[mirror_edk2.git] / EmbeddedPkg / Library / FdtLib / fdt_ro.c

/*\r
 * libfdt - Flat Device Tree manipulation\r
 * Copyright (C) 2006 David Gibson, IBM Corporation.\r
 *\r
 * libfdt is dual licensed: you can use it either under the terms of\r
 * the GPL, or the BSD license, at your option.\r
 *\r
 *  a) This library is free software; you can redistribute it and/or\r
 *     modify it under the terms of the GNU General Public License as\r
 *     published by the Free Software Foundation; either version 2 of the\r
 *     License, or (at your option) any later version.\r
 *\r
 *     This library is distributed in the hope that it will be useful,\r
 *     but WITHOUT ANY WARRANTY; without even the implied warranty of\r
 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\r
 *     GNU General Public License for more details.\r
 *\r
 *     You should have received a copy of the GNU General Public\r
 *     License along with this library; if not, write to the Free\r
 *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,\r
 *     MA 02110-1301 USA\r
 *\r
 * Alternatively,\r
 *\r
 *  b) Redistribution and use in source and binary forms, with or\r
 *     without modification, are permitted provided that the following\r
 *     conditions are met:\r
 *\r
 *     1. Redistributions of source code must retain the above\r
 *        copyright notice, this list of conditions and the following\r
 *        disclaimer.\r
 *     2. Redistributions in binary form must reproduce the above\r
 *        copyright notice, this list of conditions and the following\r
 *        disclaimer in the documentation and/or other materials\r
 *        provided with the distribution.\r
 *\r
 *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND\r
 *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,\r
 *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF\r
 *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE\r
 *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR\r
 *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,\r
 *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT\r
 *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;\r
 *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)\r
 *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN\r
 *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR\r
 *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,\r
 *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\r
 */\r
#include "libfdt_env.h"\r
\r
#include <fdt.h>\r
#include <libfdt.h>\r
\r
#include "libfdt_internal.h"\r
\r
static int\r
_fdt_nodename_eq (\r
  const void  *fdt,\r
  int         offset,\r
  const char  *s,\r
  int         len\r
  )\r
{\r
  const char  *p = fdt_offset_ptr (fdt, offset + FDT_TAGSIZE, len+1);\r
\r
  if (!p) {\r
    /* short match */\r
    return 0;\r
  }\r
\r
  if (memcmp (p, s, len) != 0) {\r
    return 0;\r
  }\r
\r
  if (p[len] == '\0') {\r
    return 1;\r
  } else if (!memchr (s, '@', len) && (p[len] == '@')) {\r
    return 1;\r
  } else {\r
    return 0;\r
  }\r
}\r
\r
const char *\r
fdt_string (\r
  const void  *fdt,\r
  int         stroffset\r
  )\r
{\r
  return (const char *)fdt + fdt_off_dt_strings (fdt) + stroffset;\r
}\r
\r
static int\r
_fdt_string_eq (\r
  const void  *fdt,\r
  int         stroffset,\r
  const char  *s,\r
  int         len\r
  )\r
{\r
  const char  *p = fdt_string (fdt, stroffset);\r
\r
  return (strlen (p) == len) && (memcmp (p, s, len) == 0);\r
}\r
\r
uint32_t\r
fdt_get_max_phandle (\r
  const void  *fdt\r
  )\r
{\r
  uint32_t  max_phandle = 0;\r
  int       offset;\r
\r
  for (offset = fdt_next_node (fdt, -1, NULL); ;\r
       offset = fdt_next_node (fdt, offset, NULL))\r
  {\r
    uint32_t  phandle;\r
\r
    if (offset == -FDT_ERR_NOTFOUND) {\r
      return max_phandle;\r
    }\r
\r
    if (offset < 0) {\r
      return (uint32_t)-1;\r
    }\r
\r
    phandle = fdt_get_phandle (fdt, offset);\r
    if (phandle == (uint32_t)-1) {\r
      continue;\r
    }\r
\r
    if (phandle > max_phandle) {\r
      max_phandle = phandle;\r
    }\r
  }\r
\r
  return 0;\r
}\r
\r
int\r
fdt_get_mem_rsv (\r
  const void  *fdt,\r
  int         n,\r
  uint64_t    *address,\r
  uint64_t    *size\r
  )\r
{\r
  FDT_CHECK_HEADER (fdt);\r
  *address = fdt64_to_cpu (_fdt_mem_rsv (fdt, n)->address);\r
  *size    = fdt64_to_cpu (_fdt_mem_rsv (fdt, n)->size);\r
  return 0;\r
}\r
\r
int\r
fdt_num_mem_rsv (\r
  const void  *fdt\r
  )\r
{\r
  int  i = 0;\r
\r
  while (fdt64_to_cpu (_fdt_mem_rsv (fdt, i)->size) != 0) {\r
    i++;\r
  }\r
\r
  return i;\r
}\r
\r
static int\r
_nextprop (\r
  const void  *fdt,\r
  int         offset\r
  )\r
{\r
  uint32_t  tag;\r
  int       nextoffset;\r
\r
  do {\r
    tag = fdt_next_tag (fdt, offset, &nextoffset);\r
\r
    switch (tag) {\r
      case FDT_END:\r
        if (nextoffset >= 0) {\r
          return -FDT_ERR_BADSTRUCTURE;\r
        } else {\r
          return nextoffset;\r
        }\r
\r
      case FDT_PROP:\r
        return offset;\r
    }\r
\r
    offset = nextoffset;\r
  } while (tag == FDT_NOP);\r
\r
  return -FDT_ERR_NOTFOUND;\r
}\r
\r
int\r
fdt_subnode_offset_namelen (\r
  const void  *fdt,\r
  int         offset,\r
  const char  *name,\r
  int         namelen\r
  )\r
{\r
  int  depth;\r
\r
  FDT_CHECK_HEADER (fdt);\r
\r
  for (depth = 0;\r
       (offset >= 0) && (depth >= 0);\r
       offset = fdt_next_node (fdt, offset, &depth))\r
  {\r
    if (  (depth == 1)\r
       && _fdt_nodename_eq (fdt, offset, name, namelen))\r
    {\r
      return offset;\r
    }\r
  }\r
\r
  if (depth < 0) {\r
    return -FDT_ERR_NOTFOUND;\r
  }\r
\r
  return offset;       /* error */\r
}\r
\r
int\r
fdt_subnode_offset (\r
  const void  *fdt,\r
  int         parentoffset,\r
  const char  *name\r
  )\r
{\r
  return fdt_subnode_offset_namelen (fdt, parentoffset, name, strlen (name));\r
}\r
\r
int\r
fdt_path_offset_namelen (\r
  const void  *fdt,\r
  const char  *path,\r
  int         namelen\r
  )\r
{\r
  const char  *end   = path + namelen;\r
  const char  *p     = path;\r
  int         offset = 0;\r
\r
  FDT_CHECK_HEADER (fdt);\r
\r
  /* see if we have an alias */\r
  if (*path != '/') {\r
    const char  *q = memchr (path, '/', end - p);\r
\r
    if (!q) {\r
      q = end;\r
    }\r
\r
    p = fdt_get_alias_namelen (fdt, p, q - p);\r
    if (!p) {\r
      return -FDT_ERR_BADPATH;\r
    }\r
\r
    offset = fdt_path_offset (fdt, p);\r
\r
    p = q;\r
  }\r
\r
  while (p < end) {\r
    const char  *q;\r
\r
    while (*p == '/') {\r
      p++;\r
      if (p == end) {\r
        return offset;\r
      }\r
    }\r
\r
    q = memchr (p, '/', end - p);\r
    if (!q) {\r
      q = end;\r
    }\r
\r
    offset = fdt_subnode_offset_namelen (fdt, offset, p, q-p);\r
    if (offset < 0) {\r
      return offset;\r
    }\r
\r
    p = q;\r
  }\r
\r
  return offset;\r
}\r
\r
int\r
fdt_path_offset (\r
  const void  *fdt,\r
  const char  *path\r
  )\r
{\r
  return fdt_path_offset_namelen (fdt, path, strlen (path));\r
}\r
\r
const char *\r
fdt_get_name (\r
  const void  *fdt,\r
  int         nodeoffset,\r
  int         *len\r
  )\r
{\r
  const struct fdt_node_header  *nh = _fdt_offset_ptr (fdt, nodeoffset);\r
  int                           err;\r
\r
  if (  ((err = fdt_check_header (fdt)) != 0)\r
     || ((err = _fdt_check_node_offset (fdt, nodeoffset)) < 0))\r
  {\r
    goto fail;\r
  }\r
\r
  if (len) {\r
    *len = strlen (nh->name);\r
  }\r
\r
  return nh->name;\r
\r
fail:\r
  if (len) {\r
    *len = err;\r
  }\r
\r
  return NULL;\r
}\r
\r
int\r
fdt_first_property_offset (\r
  const void  *fdt,\r
  int         nodeoffset\r
  )\r
{\r
  int  offset;\r
\r
  if ((offset = _fdt_check_node_offset (fdt, nodeoffset)) < 0) {\r
    return offset;\r
  }\r
\r
  return _nextprop (fdt, offset);\r
}\r
\r
int\r
fdt_next_property_offset (\r
  const void  *fdt,\r
  int         offset\r
  )\r
{\r
  if ((offset = _fdt_check_prop_offset (fdt, offset)) < 0) {\r
    return offset;\r
  }\r
\r
  return _nextprop (fdt, offset);\r
}\r
\r
const struct fdt_property *\r
fdt_get_property_by_offset (\r
  const void  *fdt,\r
  int         offset,\r
  int         *lenp\r
  )\r
{\r
  int                        err;\r
  const struct fdt_property  *prop;\r
\r
  if ((err = _fdt_check_prop_offset (fdt, offset)) < 0) {\r
    if (lenp) {\r
      *lenp = err;\r
    }\r
\r
    return NULL;\r
  }\r
\r
  prop = _fdt_offset_ptr (fdt, offset);\r
\r
  if (lenp) {\r
    *lenp = fdt32_to_cpu (prop->len);\r
  }\r
\r
  return prop;\r
}\r
\r
const struct fdt_property *\r
fdt_get_property_namelen (\r
  const void  *fdt,\r
  int         offset,\r
  const char  *name,\r
  int         namelen,\r
  int         *lenp\r
  )\r
{\r
  for (offset = fdt_first_property_offset (fdt, offset);\r
       (offset >= 0);\r
       (offset = fdt_next_property_offset (fdt, offset)))\r
  {\r
    const struct fdt_property  *prop;\r
\r
    if (!(prop = fdt_get_property_by_offset (fdt, offset, lenp))) {\r
      offset = -FDT_ERR_INTERNAL;\r
      break;\r
    }\r
\r
    if (_fdt_string_eq (\r
          fdt,\r
          fdt32_to_cpu (prop->nameoff),\r
          name,\r
          namelen\r
          ))\r
    {\r
      return prop;\r
    }\r
  }\r
\r
  if (lenp) {\r
    *lenp = offset;\r
  }\r
\r
  return NULL;\r
}\r
\r
const struct fdt_property *\r
fdt_get_property (\r
  const void  *fdt,\r
  int         nodeoffset,\r
  const char  *name,\r
  int         *lenp\r
  )\r
{\r
  return fdt_get_property_namelen (\r
           fdt,\r
           nodeoffset,\r
           name,\r
           strlen (name),\r
           lenp\r
           );\r
}\r
\r
const void *\r
fdt_getprop_namelen (\r
  const void  *fdt,\r
  int         nodeoffset,\r
  const char  *name,\r
  int         namelen,\r
  int         *lenp\r
  )\r
{\r
  const struct fdt_property  *prop;\r
\r
  prop = fdt_get_property_namelen (fdt, nodeoffset, name, namelen, lenp);\r
  if (!prop) {\r
    return NULL;\r
  }\r
\r
  return prop->data;\r
}\r
\r
const void *\r
fdt_getprop_by_offset (\r
  const void  *fdt,\r
  int         offset,\r
  const char  **namep,\r
  int         *lenp\r
  )\r
{\r
  const struct fdt_property  *prop;\r
\r
  prop = fdt_get_property_by_offset (fdt, offset, lenp);\r
  if (!prop) {\r
    return NULL;\r
  }\r
\r
  if (namep) {\r
    *namep = fdt_string (fdt, fdt32_to_cpu (prop->nameoff));\r
  }\r
\r
  return prop->data;\r
}\r
\r
const void *\r
fdt_getprop (\r
  const void  *fdt,\r
  int         nodeoffset,\r
  const char  *name,\r
  int         *lenp\r
  )\r
{\r
  return fdt_getprop_namelen (fdt, nodeoffset, name, strlen (name), lenp);\r
}\r
\r
uint32_t\r
fdt_get_phandle (\r
  const void  *fdt,\r
  int         nodeoffset\r
  )\r
{\r
  const fdt32_t  *php;\r
  int            len;\r
\r
  /* FIXME: This is a bit sub-optimal, since we potentially scan\r
   * over all the properties twice. */\r
  php = fdt_getprop (fdt, nodeoffset, "phandle", &len);\r
  if (!php || (len != sizeof (*php))) {\r
    php = fdt_getprop (fdt, nodeoffset, "linux,phandle", &len);\r
    if (!php || (len != sizeof (*php))) {\r
      return 0;\r
    }\r
  }\r
\r
  return fdt32_to_cpu (*php);\r
}\r
\r
const char *\r
fdt_get_alias_namelen (\r
  const void  *fdt,\r
  const char  *name,\r
  int         namelen\r
  )\r
{\r
  int  aliasoffset;\r
\r
  aliasoffset = fdt_path_offset (fdt, "/aliases");\r
  if (aliasoffset < 0) {\r
    return NULL;\r
  }\r
\r
  return fdt_getprop_namelen (fdt, aliasoffset, name, namelen, NULL);\r
}\r
\r
const char *\r
fdt_get_alias (\r
  const void  *fdt,\r
  const char  *name\r
  )\r
{\r
  return fdt_get_alias_namelen (fdt, name, strlen (name));\r
}\r
\r
int\r
fdt_get_path (\r
  const void  *fdt,\r
  int         nodeoffset,\r
  char        *buf,\r
  int         buflen\r
  )\r
{\r
  int         pdepth = 0, p = 0;\r
  int         offset, depth, namelen;\r
  const char  *name;\r
\r
  FDT_CHECK_HEADER (fdt);\r
\r
  if (buflen < 2) {\r
    return -FDT_ERR_NOSPACE;\r
  }\r
\r
  for (offset = 0, depth = 0;\r
       (offset >= 0) && (offset <= nodeoffset);\r
       offset = fdt_next_node (fdt, offset, &depth))\r
  {\r
    while (pdepth > depth) {\r
      do {\r
        p--;\r
      } while (buf[p-1] != '/');\r
\r
      pdepth--;\r
    }\r
\r
    if (pdepth >= depth) {\r
      name = fdt_get_name (fdt, offset, &namelen);\r
      if (!name) {\r
        return namelen;\r
      }\r
\r
      if ((p + namelen + 1) <= buflen) {\r
        memcpy (buf + p, name, namelen);\r
        p       += namelen;\r
        buf[p++] = '/';\r
        pdepth++;\r
      }\r
    }\r
\r
    if (offset == nodeoffset) {\r
      if (pdepth < (depth + 1)) {\r
        return -FDT_ERR_NOSPACE;\r
      }\r
\r
      if (p > 1) {\r
        /* special case so that root path is "/", not "" */\r
        p--;\r
      }\r
\r
      buf[p] = '\0';\r
      return 0;\r
    }\r
  }\r
\r
  if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0)) {\r
    return -FDT_ERR_BADOFFSET;\r
  } else if (offset == -FDT_ERR_BADOFFSET) {\r
    return -FDT_ERR_BADSTRUCTURE;\r
  }\r
\r
  return offset;       /* error from fdt_next_node() */\r
}\r
\r
int\r
fdt_supernode_atdepth_offset (\r
  const void  *fdt,\r
  int         nodeoffset,\r
  int         supernodedepth,\r
  int         *nodedepth\r
  )\r
{\r
  int  offset, depth;\r
  int  supernodeoffset = -FDT_ERR_INTERNAL;\r
\r
  FDT_CHECK_HEADER (fdt);\r
\r
  if (supernodedepth < 0) {\r
    return -FDT_ERR_NOTFOUND;\r
  }\r
\r
  for (offset = 0, depth = 0;\r
       (offset >= 0) && (offset <= nodeoffset);\r
       offset = fdt_next_node (fdt, offset, &depth))\r
  {\r
    if (depth == supernodedepth) {\r
      supernodeoffset = offset;\r
    }\r
\r
    if (offset == nodeoffset) {\r
      if (nodedepth) {\r
        *nodedepth = depth;\r
      }\r
\r
      if (supernodedepth > depth) {\r
        return -FDT_ERR_NOTFOUND;\r
      } else {\r
        return supernodeoffset;\r
      }\r
    }\r
  }\r
\r
  if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0)) {\r
    return -FDT_ERR_BADOFFSET;\r
  } else if (offset == -FDT_ERR_BADOFFSET) {\r
    return -FDT_ERR_BADSTRUCTURE;\r
  }\r
\r
  return offset;       /* error from fdt_next_node() */\r
}\r
\r
int\r
fdt_node_depth (\r
  const void  *fdt,\r
  int         nodeoffset\r
  )\r
{\r
  int  nodedepth;\r
  int  err;\r
\r
  err = fdt_supernode_atdepth_offset (fdt, nodeoffset, 0, &nodedepth);\r
  if (err) {\r
    return (err < 0) ? err : -FDT_ERR_INTERNAL;\r
  }\r
\r
  return nodedepth;\r
}\r
\r
int\r
fdt_parent_offset (\r
  const void  *fdt,\r
  int         nodeoffset\r
  )\r
{\r
  int  nodedepth = fdt_node_depth (fdt, nodeoffset);\r
\r
  if (nodedepth < 0) {\r
    return nodedepth;\r
  }\r
\r
  return fdt_supernode_atdepth_offset (\r
           fdt,\r
           nodeoffset,\r
           nodedepth - 1,\r
           NULL\r
           );\r
}\r
\r
int\r
fdt_node_offset_by_prop_value (\r
  const void  *fdt,\r
  int         startoffset,\r
  const char  *propname,\r
  const void  *propval,\r
  int         proplen\r
  )\r
{\r
  int         offset;\r
  const void  *val;\r
  int         len;\r
\r
  FDT_CHECK_HEADER (fdt);\r
\r
  /* FIXME: The algorithm here is pretty horrible: we scan each\r
   * property of a node in fdt_getprop(), then if that didn't\r
   * find what we want, we scan over them again making our way\r
   * to the next node.  Still it's the easiest to implement\r
   * approach; performance can come later. */\r
  for (offset = fdt_next_node (fdt, startoffset, NULL);\r
       offset >= 0;\r
       offset = fdt_next_node (fdt, offset, NULL))\r
  {\r
    val = fdt_getprop (fdt, offset, propname, &len);\r
    if (  val && (len == proplen)\r
       && (memcmp (val, propval, len) == 0))\r
    {\r
      return offset;\r
    }\r
  }\r
\r
  return offset;       /* error from fdt_next_node() */\r
}\r
\r
int\r
fdt_node_offset_by_phandle (\r
  const void  *fdt,\r
  uint32_t    phandle\r
  )\r
{\r
  int  offset;\r
\r
  if ((phandle == 0) || (phandle == -1)) {\r
    return -FDT_ERR_BADPHANDLE;\r
  }\r
\r
  FDT_CHECK_HEADER (fdt);\r
\r
  /* FIXME: The algorithm here is pretty horrible: we\r
   * potentially scan each property of a node in\r
   * fdt_get_phandle(), then if that didn't find what\r
   * we want, we scan over them again making our way to the next\r
   * node.  Still it's the easiest to implement approach;\r
   * performance can come later. */\r
  for (offset = fdt_next_node (fdt, -1, NULL);\r
       offset >= 0;\r
       offset = fdt_next_node (fdt, offset, NULL))\r
  {\r
    if (fdt_get_phandle (fdt, offset) == phandle) {\r
      return offset;\r
    }\r
  }\r
\r
  return offset;       /* error from fdt_next_node() */\r
}\r
\r
int\r
fdt_stringlist_contains (\r
  const char  *strlist,\r
  int         listlen,\r
  const char  *str\r
  )\r
{\r
  int         len = strlen (str);\r
  const char  *p;\r
\r
  while (listlen >= len) {\r
    if (memcmp (str, strlist, len+1) == 0) {\r
      return 1;\r
    }\r
\r
    p = memchr (strlist, '\0', listlen);\r
    if (!p) {\r
      return 0;                   /* malformed strlist.. */\r
    }\r
\r
    listlen -= (p-strlist) + 1;\r
    strlist  = p + 1;\r
  }\r
\r
  return 0;\r
}\r
\r
int\r
fdt_stringlist_count (\r
  const void  *fdt,\r
  int         nodeoffset,\r
  const char  *property\r
  )\r
{\r
  const char  *list, *end;\r
  int         length, count = 0;\r
\r
  list = fdt_getprop (fdt, nodeoffset, property, &length);\r
  if (!list) {\r
    return length;\r
  }\r
\r
  end = list + length;\r
\r
  while (list < end) {\r
    length = strnlen (list, end - list) + 1;\r
\r
    /* Abort if the last string isn't properly NUL-terminated. */\r
    if (list + length > end) {\r
      return -FDT_ERR_BADVALUE;\r
    }\r
\r
    list += length;\r
    count++;\r
  }\r
\r
  return count;\r
}\r
\r
int\r
fdt_stringlist_search (\r
  const void  *fdt,\r
  int         nodeoffset,\r
  const char  *property,\r
  const char  *string\r
  )\r
{\r
  int         length, len, idx = 0;\r
  const char  *list, *end;\r
\r
  list = fdt_getprop (fdt, nodeoffset, property, &length);\r
  if (!list) {\r
    return length;\r
  }\r
\r
  len = strlen (string) + 1;\r
  end = list + length;\r
\r
  while (list < end) {\r
    length = strnlen (list, end - list) + 1;\r
\r
    /* Abort if the last string isn't properly NUL-terminated. */\r
    if (list + length > end) {\r
      return -FDT_ERR_BADVALUE;\r
    }\r
\r
    if ((length == len) && (memcmp (list, string, length) == 0)) {\r
      return idx;\r
    }\r
\r
    list += length;\r
    idx++;\r
  }\r
\r
  return -FDT_ERR_NOTFOUND;\r
}\r
\r
const char *\r
fdt_stringlist_get (\r
  const void  *fdt,\r
  int         nodeoffset,\r
  const char  *property,\r
  int         idx,\r
  int         *lenp\r
  )\r
{\r
  const char  *list, *end;\r
  int         length;\r
\r
  list = fdt_getprop (fdt, nodeoffset, property, &length);\r
  if (!list) {\r
    if (lenp) {\r
      *lenp = length;\r
    }\r
\r
    return NULL;\r
  }\r
\r
  end = list + length;\r
\r
  while (list < end) {\r
    length = strnlen (list, end - list) + 1;\r
\r
    /* Abort if the last string isn't properly NUL-terminated. */\r
    if (list + length > end) {\r
      if (lenp) {\r
        *lenp = -FDT_ERR_BADVALUE;\r
      }\r
\r
      return NULL;\r
    }\r
\r
    if (idx == 0) {\r
      if (lenp) {\r
        *lenp = length - 1;\r
      }\r
\r
      return list;\r
    }\r
\r
    list += length;\r
    idx--;\r
  }\r
\r
  if (lenp) {\r
    *lenp = -FDT_ERR_NOTFOUND;\r
  }\r
\r
  return NULL;\r
}\r
\r
int\r
fdt_node_check_compatible (\r
  const void  *fdt,\r
  int         nodeoffset,\r
  const char  *compatible\r
  )\r
{\r
  const void  *prop;\r
  int         len;\r
\r
  prop = fdt_getprop (fdt, nodeoffset, "compatible", &len);\r
  if (!prop) {\r
    return len;\r
  }\r
\r
  return !fdt_stringlist_contains (prop, len, compatible);\r
}\r
\r
int\r
fdt_node_offset_by_compatible (\r
  const void  *fdt,\r
  int         startoffset,\r
  const char  *compatible\r
  )\r
{\r
  int  offset, err;\r
\r
  FDT_CHECK_HEADER (fdt);\r
\r
  /* FIXME: The algorithm here is pretty horrible: we scan each\r
   * property of a node in fdt_node_check_compatible(), then if\r
   * that didn't find what we want, we scan over them again\r
   * making our way to the next node.  Still it's the easiest to\r
   * implement approach; performance can come later. */\r
  for (offset = fdt_next_node (fdt, startoffset, NULL);\r
       offset >= 0;\r
       offset = fdt_next_node (fdt, offset, NULL))\r
  {\r
    err = fdt_node_check_compatible (fdt, offset, compatible);\r
    if ((err < 0) && (err != -FDT_ERR_NOTFOUND)) {\r
      return err;\r
    } else if (err == 0) {\r
      return offset;\r
    }\r
  }\r
\r
  return offset;       /* error from fdt_next_node() */\r
}\r