1// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
  2/*
  3 * libfdt - Flat Device Tree manipulation
  4 * Copyright (C) 2014 David Gibson <david@gibson.dropbear.id.au>
  5 * Copyright (C) 2018 embedded brains GmbH
  6 */
  7#include "libfdt_env.h"
  8
  9#include <fdt.h>
 10#include <libfdt.h>
 11
 12#include "libfdt_internal.h"
 13
 14static int fdt_cells(const void *fdt, int nodeoffset, const char *name)
 15{
 16	const fdt32_t *c;
 17	uint32_t val;
 18	int len;
 19
 20	c = fdt_getprop(fdt, nodeoffset, name, &len);
 21	if (!c)
 22		return len;
 23
 24	if (len != sizeof(*c))
 25		return -FDT_ERR_BADNCELLS;
 26
 27	val = fdt32_to_cpu(*c);
 28	if (val > FDT_MAX_NCELLS)
 29		return -FDT_ERR_BADNCELLS;
 30
 31	return (int)val;
 32}
 33
 34int fdt_address_cells(const void *fdt, int nodeoffset)
 35{
 36	int val;
 37
 38	val = fdt_cells(fdt, nodeoffset, "#address-cells");
 39	if (val == 0)
 40		return -FDT_ERR_BADNCELLS;
 41	if (val == -FDT_ERR_NOTFOUND)
 42		return 2;
 43	return val;
 44}
 45
 46int fdt_size_cells(const void *fdt, int nodeoffset)
 47{
 48	int val;
 49
 50	val = fdt_cells(fdt, nodeoffset, "#size-cells");
 51	if (val == -FDT_ERR_NOTFOUND)
 52		return 1;
 53	return val;
 54}
 55
 56/* This function assumes that [address|size]_cells is 1 or 2 */
 57int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
 58			     const char *name, uint64_t addr, uint64_t size)
 59{
 60	int addr_cells, size_cells, ret;
 61	uint8_t data[sizeof(fdt64_t) * 2], *prop;
 62
 63	ret = fdt_address_cells(fdt, parent);
 64	if (ret < 0)
 65		return ret;
 66	addr_cells = ret;
 67
 68	ret = fdt_size_cells(fdt, parent);
 69	if (ret < 0)
 70		return ret;
 71	size_cells = ret;
 72
 73	/* check validity of address */
 74	prop = data;
 75	if (addr_cells == 1) {
 76		if ((addr > UINT32_MAX) || (((uint64_t) UINT32_MAX + 1 - addr) < size))
 77			return -FDT_ERR_BADVALUE;
 78
 79		fdt32_st(prop, (uint32_t)addr);
 80	} else if (addr_cells == 2) {
 81		fdt64_st(prop, addr);
 82	} else {
 83		return -FDT_ERR_BADNCELLS;
 84	}
 85
 86	/* check validity of size */
 87	prop += addr_cells * sizeof(fdt32_t);
 88	if (size_cells == 1) {
 89		if (size > UINT32_MAX)
 90			return -FDT_ERR_BADVALUE;
 91
 92		fdt32_st(prop, (uint32_t)size);
 93	} else if (size_cells == 2) {
 94		fdt64_st(prop, size);
 95	} else {
 96		return -FDT_ERR_BADNCELLS;
 97	}
 98
 99	return fdt_appendprop(fdt, nodeoffset, name, data,
100			      (addr_cells + size_cells) * sizeof(fdt32_t));
101}