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}
102