blob: 2055734012a1009438adf10b2d2e232f5b647c3d [file] [log] [blame]
/*
* libfdt - Flat Device Tree manipulation
* Copyright (C) 2006 David Gibson, IBM Corporation.
* SPDX-License-Identifier: GPL-2.0+ BSD-2-Clause
*/
#include <libfdt_env.h>
#ifndef USE_HOSTCC
#include <fdt.h>
#include <libfdt.h>
#else
#include "fdt_host.h"
#endif
#include "libfdt_internal.h"
int fdt_check_header(const void *fdt)
{
if (fdt_magic(fdt) == FDT_MAGIC) {
/* Complete tree */
if (fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION)
return -FDT_ERR_BADVERSION;
if (fdt_last_comp_version(fdt) > FDT_LAST_SUPPORTED_VERSION)
return -FDT_ERR_BADVERSION;
} else if (fdt_magic(fdt) == FDT_SW_MAGIC) {
/* Unfinished sequential-write blob */
if (fdt_size_dt_struct(fdt) == 0)
return -FDT_ERR_BADSTATE;
} else {
return -FDT_ERR_BADMAGIC;
}
return 0;
}
const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int len)
{
unsigned absoffset = offset + fdt_off_dt_struct(fdt);
if ((absoffset < offset)
|| ((absoffset + len) < absoffset)
|| (absoffset + len) > fdt_totalsize(fdt))
return NULL;
if (fdt_version(fdt) >= 0x11)
if (((offset + len) < offset)
|| ((offset + len) > fdt_size_dt_struct(fdt)))
return NULL;
return _fdt_offset_ptr(fdt, offset);
}
uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
{
const fdt32_t *tagp, *lenp;
uint32_t tag;
int offset = startoffset;
const char *p;
*nextoffset = -FDT_ERR_TRUNCATED;
tagp = fdt_offset_ptr(fdt, offset, FDT_TAGSIZE);
if (!tagp)
return FDT_END; /* premature end */
tag = fdt32_to_cpu(*tagp);
offset += FDT_TAGSIZE;
*nextoffset = -FDT_ERR_BADSTRUCTURE;
switch (tag) {
case FDT_BEGIN_NODE:
/* skip name */
do {
p = fdt_offset_ptr(fdt, offset++, 1);
} while (p && (*p != '\0'));
if (!p)
return FDT_END; /* premature end */
break;
case FDT_PROP:
lenp = fdt_offset_ptr(fdt, offset, sizeof(*lenp));
if (!lenp)
return FDT_END; /* premature end */
/* skip-name offset, length and value */
offset += sizeof(struct fdt_property) - FDT_TAGSIZE
+ fdt32_to_cpu(*lenp);
break;
case FDT_END:
case FDT_END_NODE:
case FDT_NOP:
break;
default:
return FDT_END;
}
if (!fdt_offset_ptr(fdt, startoffset, offset - startoffset))
return FDT_END; /* premature end */
*nextoffset = FDT_TAGALIGN(offset);
return tag;
}
int _fdt_check_node_offset(const void *fdt, int offset)
{
if ((offset < 0) || (offset % FDT_TAGSIZE)
|| (fdt_next_tag(fdt, offset, &offset) != FDT_BEGIN_NODE))
return -FDT_ERR_BADOFFSET;
return offset;
}
int _fdt_check_prop_offset(const void *fdt, int offset)
{
if ((offset < 0) || (offset % FDT_TAGSIZE)
|| (fdt_next_tag(fdt, offset, &offset) != FDT_PROP))
return -FDT_ERR_BADOFFSET;
return offset;
}
int fdt_next_node(const void *fdt, int offset, int *depth)
{
int nextoffset = 0;
uint32_t tag;
if (offset >= 0)
if ((nextoffset = _fdt_check_node_offset(fdt, offset)) < 0)
return nextoffset;
do {
offset = nextoffset;
tag = fdt_next_tag(fdt, offset, &nextoffset);
switch (tag) {
case FDT_PROP:
case FDT_NOP:
break;
case FDT_BEGIN_NODE:
if (depth)
(*depth)++;
break;
case FDT_END_NODE:
if (depth && ((--(*depth)) < 0))
return nextoffset;
break;
case FDT_END:
if ((nextoffset >= 0)
|| ((nextoffset == -FDT_ERR_TRUNCATED) && !depth))
return -FDT_ERR_NOTFOUND;
else
return nextoffset;
}
} while (tag != FDT_BEGIN_NODE);
return offset;
}
int fdt_first_subnode(const void *fdt, int offset)
{
int depth = 0;
offset = fdt_next_node(fdt, offset, &depth);
if (offset < 0 || depth != 1)
return -FDT_ERR_NOTFOUND;
return offset;
}
int fdt_next_subnode(const void *fdt, int offset)
{
int depth = 1;
/*
* With respect to the parent, the depth of the next subnode will be
* the same as the last.
*/
do {
offset = fdt_next_node(fdt, offset, &depth);
if (offset < 0 || depth < 1)
return -FDT_ERR_NOTFOUND;
} while (depth > 1);
return offset;
}
const char *_fdt_find_string(const char *strtab, int tabsize, const char *s)
{
int len = strlen(s) + 1;
const char *last = strtab + tabsize - len;
const char *p;
for (p = strtab; p <= last; p++)
if (memcmp(p, s, len) == 0)
return p;
return NULL;
}
int fdt_move(const void *fdt, void *buf, int bufsize)
{
FDT_CHECK_HEADER(fdt);
if (fdt_totalsize(fdt) > bufsize)
return -FDT_ERR_NOSPACE;
memmove(buf, fdt, fdt_totalsize(fdt));
return 0;
}