aboutsummaryrefslogtreecommitdiffstats
path: root/arch/powerpc/boot/libfdt-wrapper.c
blob: 9276327bc2bb1995343dabf417f2c3927386cd95 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
/*
 * This file does the necessary interface mapping between the bootwrapper
 * device tree operations and the interface provided by shared source
 * files flatdevicetree.[ch].
 *
 * Copyright 2007 David Gibson, IBM Corporation.
 *
 * 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
 */

#include <stddef.h>
#include <stdio.h>
#include <page.h>
#include <libfdt.h>
#include "ops.h"

#define DEBUG	0
#define BAD_ERROR(err)	(((err) < 0) \
			 && ((err) != -FDT_ERR_NOTFOUND) \
			 && ((err) != -FDT_ERR_EXISTS))

#define check_err(err) \
	({ \
		if (BAD_ERROR(err) || ((err < 0) && DEBUG)) \
			printf("%s():%d  %s\n\r", __func__, __LINE__, \
			       fdt_strerror(err)); \
		if (BAD_ERROR(err)) \
			exit(); \
		(err < 0) ? -1 : 0; \
	})

#define offset_devp(off)	\
	({ \
		int _offset = (off); \
		check_err(_offset) ? NULL : (void *)(_offset+1); \
	})

#define devp_offset_find(devp)	(((int)(devp))-1)
#define devp_offset(devp)	(devp ? ((int)(devp))-1 : 0)

static void *fdt;
static void *buf; /* = NULL */

#define EXPAND_GRANULARITY	1024

static void expand_buf(int minexpand)
{
	int size = fdt_totalsize(fdt);
	int rc;

	size = _ALIGN(size + minexpand, EXPAND_GRANULARITY);
	buf = platform_ops.realloc(buf, size);
	if (!buf)
		fatal("Couldn't find %d bytes to expand device tree\n\r", size);
	rc = fdt_open_into(fdt, buf, size);
	if (rc != 0)
		fatal("Couldn't expand fdt into new buffer: %s\n\r",
		      fdt_strerror(rc));

	fdt = buf;
}

static void *fdt_wrapper_finddevice(const char *path)
{
	return offset_devp(fdt_path_offset(fdt, path));
}

static int fdt_wrapper_getprop(const void *devp, const char *name,
			       void *buf, const int buflen)
{
	const void *p;
	int len;

	p = fdt_getprop(fdt, devp_offset(devp), name, &len);
	if (!p)
		return check_err(len);
	memcpy(buf, p, min(len, buflen));
	return len;
}

static int fdt_wrapper_setprop(const void *devp, const char *name,
			       const void *buf, const int len)
{
	int rc;

	rc = fdt_setprop(fdt, devp_offset(devp), name, buf, len);
	if (rc == -FDT_ERR_NOSPACE) {
		expand_buf(len + 16);
		rc = fdt_setprop(fdt, devp_offset(devp), name, buf, len);
	}

	return check_err(rc);
}

static int fdt_wrapper_del_node(const void *devp)
{
	return fdt_del_node(fdt, devp_offset(devp));
}

static void *fdt_wrapper_get_parent(const void *devp)
{
	return offset_devp(fdt_parent_offset(fdt, devp_offset(devp)));
}

static void *fdt_wrapper_create_node(const void *devp, const char *name)
{
	int offset;

	offset = fdt_add_subnode(fdt, devp_offset(devp), name);
	if (offset == -FDT_ERR_NOSPACE) {
		expand_buf(strlen(name) + 16);
		offset = fdt_add_subnode(fdt, devp_offset(devp), name);
	}

	return offset_devp(offset);
}

static void *fdt_wrapper_find_node_by_prop_value(const void *prev,
						 const char *name,
						 const char *val,
						 int len)
{
	int offset = fdt_node_offset_by_prop_value(fdt, devp_offset_find(prev),
	                                           name, val, len);
	return offset_devp(offset);
}

static void *fdt_wrapper_find_node_by_compatible(const void *prev,
						 const char *val)
{
	int offset = fdt_node_offset_by_compatible(fdt, devp_offset_find(prev),
	                                           val);
	return offset_devp(offset);
}

static char *fdt_wrapper_get_path(const void *devp, char *buf, int len)
{
	int rc;

	rc = fdt_get_path(fdt, devp_offset(devp), buf, len);
	if (check_err(rc))
		return NULL;
	return buf;
}

static unsigned long fdt_wrapper_finalize(void)
{
	int rc;

	rc = fdt_pack(fdt);
	if (rc != 0)
		fatal("Couldn't pack flat tree: %s\n\r",
		      fdt_strerror(rc));
	return (unsigned long)fdt;
}

void fdt_init(void *blob)
{
	int err;
	int bufsize;

	dt_ops.finddevice = fdt_wrapper_finddevice;
	dt_ops.getprop = fdt_wrapper_getprop;
	dt_ops.setprop = fdt_wrapper_setprop;
	dt_ops.get_parent = fdt_wrapper_get_parent;
	dt_ops.create_node = fdt_wrapper_create_node;
	dt_ops.find_node_by_prop_value = fdt_wrapper_find_node_by_prop_value;
	dt_ops.find_node_by_compatible = fdt_wrapper_find_node_by_compatible;
	dt_ops.del_node = fdt_wrapper_del_node;
	dt_ops.get_path = fdt_wrapper_get_path;
	dt_ops.finalize = fdt_wrapper_finalize;

	/* Make sure the dt blob is the right version and so forth */
	fdt = blob;
	bufsize = fdt_totalsize(fdt) + 4;
	buf = malloc(bufsize);
	if(!buf)
		fatal("malloc failed. can't relocate the device tree\n\r");

	err = fdt_open_into(fdt, buf, bufsize);

	if (err != 0)
		fatal("fdt_init(): %s\n\r", fdt_strerror(err));

	fdt = buf;
}