[mirror_ubuntu-bionic-kernel.git] / scripts / dtc / libfdt / fdt.c

/*
 * libfdt - Flat Device Tree manipulation
 * Copyright (C) 2006 David Gibson, IBM Corporation.
 *
 * libfdt is dual licensed: you can use it either under the terms of
 * the GPL, or the BSD license, at your option.
 *
 *  a) This library is free software; you can redistribute it and/or
 *     modify it under the terms of the GNU General Public License as
 *     published by the Free Software Foundation; either version 2 of the
 *     License, or (at your option) any later version.
 *
 *     This library is distributed in the hope that it will be useful,
 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *     GNU General Public License for more details.
 *
 *     You should have received a copy of the GNU General Public
 *     License along with this library; if not, write to the Free
 *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
 *     MA 02110-1301 USA
 *
 * Alternatively,
 *
 *  b) Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *     1. Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *     2. Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
#include "libfdt_env.h"

#include <fdt.h>
#include <libfdt.h>

#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;
}
Commit	Line	Data
1cade994 DG	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	int fdt_check_header(const void *fdt)
	59	{
	60	if (fdt_magic(fdt) == FDT_MAGIC) {
	61	/* Complete tree */
	62	if (fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION)
	63	return -FDT_ERR_BADVERSION;
	64	if (fdt_last_comp_version(fdt) > FDT_LAST_SUPPORTED_VERSION)
65	return -FDT_ERR_BADVERSION;
ed95d745	66	} else if (fdt_magic(fdt) == FDT_SW_MAGIC) {
1cade994 DG	67	/* Unfinished sequential-write blob */
	68	if (fdt_size_dt_struct(fdt) == 0)
	69	return -FDT_ERR_BADSTATE;
	70	} else {
	71	return -FDT_ERR_BADMAGIC;
	72	}
	73
	74	return 0;
	75	}
	76
cd296721	77	const void fdt_offset_ptr(const void fdt, int offset, unsigned int len)
1cade994	78	{
91feabc2 RH	79	unsigned absoffset = offset + fdt_off_dt_struct(fdt);
	80
	81	if ((absoffset < offset)
	82	\|\| ((absoffset + len) < absoffset)
	83	\|\| (absoffset + len) > fdt_totalsize(fdt))
	84	return NULL;
1cade994 DG	85
	86	if (fdt_version(fdt) >= 0x11)
	87	if (((offset + len) < offset)
	88	\|\| ((offset + len) > fdt_size_dt_struct(fdt)))
	89	return NULL;
	90
91feabc2	91	return _fdt_offset_ptr(fdt, offset);
1cade994 DG	92	}
1cade994 DG	93
cd296721	94	uint32_t fdt_next_tag(const void fdt, int startoffset, int nextoffset)
1cade994	95	{
47605971	96	const fdt32_t tagp, lenp;
1cade994	97	uint32_t tag;
cd296721	98	int offset = startoffset;
1cade994 DG	99	const char *p;
1cade994 DG	100
cd296721	101	*nextoffset = -FDT_ERR_TRUNCATED;
1cade994	102	tagp = fdt_offset_ptr(fdt, offset, FDT_TAGSIZE);
cd296721	103	if (!tagp)
1cade994 DG	104	return FDT_END; /* premature end */
	105	tag = fdt32_to_cpu(*tagp);
	106	offset += FDT_TAGSIZE;
	107
cd296721	108	*nextoffset = -FDT_ERR_BADSTRUCTURE;
1cade994 DG	109	switch (tag) {
	110	case FDT_BEGIN_NODE:
	111	/* skip name */
	112	do {
	113	p = fdt_offset_ptr(fdt, offset++, 1);
	114	} while (p && (*p != '\0'));
cd296721 SW	115	if (!p)
cd296721 SW	116	return FDT_END; /* premature end */
1cade994	117	break;
cd296721	118
1cade994 DG	119	case FDT_PROP:
1cade994 DG	120	lenp = fdt_offset_ptr(fdt, offset, sizeof(*lenp));
cd296721 SW	121	if (!lenp)
	122	return FDT_END; /* premature end */
	123	/* skip-name offset, length and value */
	124	offset += sizeof(struct fdt_property) - FDT_TAGSIZE
	125	+ fdt32_to_cpu(*lenp);
	126	break;
	127
	128	case FDT_END:
	129	case FDT_END_NODE:
	130	case FDT_NOP:
1cade994	131	break;
cd296721 SW	132
	133	default:
	134	return FDT_END;
1cade994 DG	135	}
1cade994 DG	136
cd296721 SW	137	if (!fdt_offset_ptr(fdt, startoffset, offset - startoffset))
cd296721 SW	138	return FDT_END; /* premature end */
1cade994	139
cd296721	140	*nextoffset = FDT_TAGALIGN(offset);
1cade994 DG	141	return tag;
	142	}
	143
ed95d745 DG	144	int _fdt_check_node_offset(const void *fdt, int offset)
	145	{
	146	if ((offset < 0) \|\| (offset % FDT_TAGSIZE)
	147	\|\| (fdt_next_tag(fdt, offset, &offset) != FDT_BEGIN_NODE))
	148	return -FDT_ERR_BADOFFSET;
	149
	150	return offset;
	151	}
	152
cd296721 SW	153	int _fdt_check_prop_offset(const void *fdt, int offset)
	154	{
	155	if ((offset < 0) \|\| (offset % FDT_TAGSIZE)
	156	\|\| (fdt_next_tag(fdt, offset, &offset) != FDT_PROP))
	157	return -FDT_ERR_BADOFFSET;
	158
	159	return offset;
	160	}
	161
ed95d745 DG	162	int fdt_next_node(const void fdt, int offset, int depth)
	163	{
	164	int nextoffset = 0;
	165	uint32_t tag;
	166
	167	if (offset >= 0)
	168	if ((nextoffset = _fdt_check_node_offset(fdt, offset)) < 0)
	169	return nextoffset;
	170
	171	do {
	172	offset = nextoffset;
	173	tag = fdt_next_tag(fdt, offset, &nextoffset);
	174
	175	switch (tag) {
	176	case FDT_PROP:
	177	case FDT_NOP:
	178	break;
	179
	180	case FDT_BEGIN_NODE:
	181	if (depth)
	182	(*depth)++;
	183	break;
	184
	185	case FDT_END_NODE:
cd296721 SW	186	if (depth && ((--(*depth)) < 0))
cd296721 SW	187	return nextoffset;
ed95d745 DG	188	break;
	189
	190	case FDT_END:
cd296721 SW	191	if ((nextoffset >= 0)
	192	\|\| ((nextoffset == -FDT_ERR_TRUNCATED) && !depth))
	193	return -FDT_ERR_NOTFOUND;
	194	else
	195	return nextoffset;
ed95d745 DG	196	}
	197	} while (tag != FDT_BEGIN_NODE);
	198
	199	return offset;
	200	}
	201
47605971 RH	202	int fdt_first_subnode(const void *fdt, int offset)
	203	{
	204	int depth = 0;
	205
	206	offset = fdt_next_node(fdt, offset, &depth);
	207	if (offset < 0 \|\| depth != 1)
	208	return -FDT_ERR_NOTFOUND;
	209
	210	return offset;
	211	}
	212
	213	int fdt_next_subnode(const void *fdt, int offset)
	214	{
	215	int depth = 1;
	216
	217	/*
	218	* With respect to the parent, the depth of the next subnode will be
	219	* the same as the last.
	220	*/
	221	do {
	222	offset = fdt_next_node(fdt, offset, &depth);
	223	if (offset < 0 \|\| depth < 1)
	224	return -FDT_ERR_NOTFOUND;
	225	} while (depth > 1);
	226
	227	return offset;
	228	}
	229
1cade994 DG	230	const char _fdt_find_string(const char strtab, int tabsize, const char *s)
	231	{
	232	int len = strlen(s) + 1;
	233	const char *last = strtab + tabsize - len;
	234	const char *p;
	235
	236	for (p = strtab; p <= last; p++)
ed95d745	237	if (memcmp(p, s, len) == 0)
1cade994 DG	238	return p;
	239	return NULL;
	240	}
	241
	242	int fdt_move(const void fdt, void buf, int bufsize)
	243	{
ed95d745	244	FDT_CHECK_HEADER(fdt);
1cade994 DG	245
	246	if (fdt_totalsize(fdt) > bufsize)
	247	return -FDT_ERR_NOSPACE;
	248
	249	memmove(buf, fdt, fdt_totalsize(fdt));
	250	return 0;
	251	}