xref: /netbsd-src/sys/external/bsd/libfdt/dist/fdt_addresses.c (revision 5a485aa93ac82c3d325292e0224456d0b90f9a60)
1 /*	$NetBSD: fdt_addresses.c,v 1.1.1.3 2019/12/22 12:30:37 skrll Exp $	*/
2 
3 // SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
4 /*
5  * libfdt - Flat Device Tree manipulation
6  * Copyright (C) 2014 David Gibson <david@gibson.dropbear.id.au>
7  * Copyright (C) 2018 embedded brains GmbH
8  */
9 #include "libfdt_env.h"
10 
11 #include <fdt.h>
12 #include <libfdt.h>
13 
14 #include "libfdt_internal.h"
15 
fdt_cells(const void * fdt,int nodeoffset,const char * name)16 static int fdt_cells(const void *fdt, int nodeoffset, const char *name)
17 {
18 	const fdt32_t *c;
19 	uint32_t val;
20 	int len;
21 
22 	c = fdt_getprop(fdt, nodeoffset, name, &len);
23 	if (!c)
24 		return len;
25 
26 	if (len != sizeof(*c))
27 		return -FDT_ERR_BADNCELLS;
28 
29 	val = fdt32_to_cpu(*c);
30 	if (val > FDT_MAX_NCELLS)
31 		return -FDT_ERR_BADNCELLS;
32 
33 	return (int)val;
34 }
35 
fdt_address_cells(const void * fdt,int nodeoffset)36 int fdt_address_cells(const void *fdt, int nodeoffset)
37 {
38 	int val;
39 
40 	val = fdt_cells(fdt, nodeoffset, "#address-cells");
41 	if (val == 0)
42 		return -FDT_ERR_BADNCELLS;
43 	if (val == -FDT_ERR_NOTFOUND)
44 		return 2;
45 	return val;
46 }
47 
fdt_size_cells(const void * fdt,int nodeoffset)48 int fdt_size_cells(const void *fdt, int nodeoffset)
49 {
50 	int val;
51 
52 	val = fdt_cells(fdt, nodeoffset, "#size-cells");
53 	if (val == -FDT_ERR_NOTFOUND)
54 		return 1;
55 	return val;
56 }
57 
58 /* This function assumes that [address|size]_cells is 1 or 2 */
fdt_appendprop_addrrange(void * fdt,int parent,int nodeoffset,const char * name,uint64_t addr,uint64_t size)59 int fdt_appendprop_addrrange(void *fdt, int parent, int nodeoffset,
60 			     const char *name, uint64_t addr, uint64_t size)
61 {
62 	int addr_cells, size_cells, ret;
63 	uint8_t data[sizeof(fdt64_t) * 2], *prop;
64 
65 	ret = fdt_address_cells(fdt, parent);
66 	if (ret < 0)
67 		return ret;
68 	addr_cells = ret;
69 
70 	ret = fdt_size_cells(fdt, parent);
71 	if (ret < 0)
72 		return ret;
73 	size_cells = ret;
74 
75 	/* check validity of address */
76 	prop = data;
77 	if (addr_cells == 1) {
78 		if ((addr > UINT32_MAX) || ((UINT32_MAX + 1 - addr) < size))
79 			return -FDT_ERR_BADVALUE;
80 
81 		fdt32_st(prop, (uint32_t)addr);
82 	} else if (addr_cells == 2) {
83 		fdt64_st(prop, addr);
84 	} else {
85 		return -FDT_ERR_BADNCELLS;
86 	}
87 
88 	/* check validity of size */
89 	prop += addr_cells * sizeof(fdt32_t);
90 	if (size_cells == 1) {
91 		if (size > UINT32_MAX)
92 			return -FDT_ERR_BADVALUE;
93 
94 		fdt32_st(prop, (uint32_t)size);
95 	} else if (size_cells == 2) {
96 		fdt64_st(prop, size);
97 	} else {
98 		return -FDT_ERR_BADNCELLS;
99 	}
100 
101 	return fdt_appendprop(fdt, nodeoffset, name, data,
102 			      (addr_cells + size_cells) * sizeof(fdt32_t));
103 }
104