libfdt/fdt_addresses.c

/*
 * libfdt - Flat Device Tree manipulation
 * Copyright (C) 2014 David Gibson <david@gibson.dropbear.id.au>
 * Copyright (C) 2018 embedded brains GmbH
 *
 * 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"

static int fdt_cells(const void *fdt, int nodeoffset, const char *name)
{
	const fdt32_t *c;
	int val;
	int len;

	c = fdt_getprop(fdt, nodeoffset, name, &len);
	if (!c)
		return len;

	if (len != sizeof(*c))
		return -FDT_ERR_BADNCELLS;

	val = fdt32_to_cpu(*c);
	if ((val <= 0) || (val > FDT_MAX_NCELLS))
		return -FDT_ERR_BADNCELLS;

	return val;
}

int fdt_address_cells(const void *fdt, int nodeoffset)
{
	int val;

	val = fdt_cells(fdt, nodeoffset, "#address-cells");
	if (val == -FDT_ERR_NOTFOUND)
		return 2;
	return val;
}

int fdt_size_cells(const void *fdt, int nodeoffset)
{
	int val;

	val = fdt_cells(fdt, nodeoffset, "#size-cells");
	if (val == -FDT_ERR_NOTFOUND)
		return 1;
	return val;
}

/* This function assumes that [address|size]_cells is 1 or 2 */
int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
			     const char *name, uint64_t addr, uint64_t size)
{
	int addr_cells, size_cells, ret;
	uint8_t data[sizeof(fdt64_t) * 2], *prop;

	ret = fdt_address_cells(fdt, parent);
	if (ret < 0)
		return ret;
	addr_cells = ret;

	ret = fdt_size_cells(fdt, parent);
	if (ret < 0)
		return ret;
	size_cells = ret;

	/* check validity of address */
	prop = data;
	if (addr_cells == 1) {
		if ((addr > UINT32_MAX) || ((UINT32_MAX + 1 - addr) < size))
			return -FDT_ERR_BADVALUE;

		fdt32_st(prop, (uint32_t)addr);
	} else if (addr_cells == 2) {
		fdt64_st(prop, addr);
	} else {
		return -FDT_ERR_BADNCELLS;
	}

	/* check validity of size */
	prop += addr_cells * sizeof(fdt32_t);
	if (size_cells == 1) {
		if (size > UINT32_MAX)
			return -FDT_ERR_BADVALUE;

		fdt32_st(prop, (uint32_t)size);
	} else if (size_cells == 2) {
		fdt64_st(prop, size);
	} else {
		return -FDT_ERR_BADNCELLS;
	}

	return fdt_appendprop(fdt, nodeoffset, name, data,
			      (addr_cells + size_cells) * sizeof(fdt32_t));
}