1/*
2 * This file does the necessary interface mapping between the bootwrapper
3 * device tree operations and the interface provided by shared source
4 * files flatdevicetree.[ch].
5 *
6 * Copyright 2007 David Gibson, IBM Corporation.
7 *
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of the
11 * License, or (at your option) any later version.
12 *
13 * This library is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 * General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this library; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
21 * 02110-1301 USA
22 */
23
24#include <stddef.h>
25#include <stdio.h>
26#include <page.h>
27#include <libfdt.h>
28#include "ops.h"
29
30#define DEBUG	0
31#define BAD_ERROR(err)	(((err) < 0) \
32			 && ((err) != -FDT_ERR_NOTFOUND) \
33			 && ((err) != -FDT_ERR_EXISTS))
34
35#define check_err(err) \
36	({ \
37		if (BAD_ERROR(err) || ((err < 0) && DEBUG)) \
38			printf("%s():%d  %s\n\r", __func__, __LINE__, \
39			       fdt_strerror(err)); \
40		if (BAD_ERROR(err)) \
41			exit(); \
42		(err < 0) ? -1 : 0; \
43	})
44
45#define offset_devp(off)	\
46	({ \
47		unsigned long _offset = (off); \
48		check_err(_offset) ? NULL : (void *)(_offset+1); \
49	})
50
51#define devp_offset_find(devp)	(((unsigned long)(devp))-1)
52#define devp_offset(devp)	(devp ? ((unsigned long)(devp))-1 : 0)
53
54static void *fdt;
55static void *buf; /* = NULL */
56
57#define EXPAND_GRANULARITY	1024
58
59static void expand_buf(int minexpand)
60{
61	int size = fdt_totalsize(fdt);
62	int rc;
63
64	size = _ALIGN(size + minexpand, EXPAND_GRANULARITY);
65	buf = platform_ops.realloc(buf, size);
66	if (!buf)
67		fatal("Couldn't find %d bytes to expand device tree\n\r", size);
68	rc = fdt_open_into(fdt, buf, size);
69	if (rc != 0)
70		fatal("Couldn't expand fdt into new buffer: %s\n\r",
71		      fdt_strerror(rc));
72
73	fdt = buf;
74}
75
76static void *fdt_wrapper_finddevice(const char *path)
77{
78	return offset_devp(fdt_path_offset(fdt, path));
79}
80
81static int fdt_wrapper_getprop(const void *devp, const char *name,
82			       void *buf, const int buflen)
83{
84	const void *p;
85	int len;
86
87	p = fdt_getprop(fdt, devp_offset(devp), name, &len);
88	if (!p)
89		return check_err(len);
90	memcpy(buf, p, min(len, buflen));
91	return len;
92}
93
94static int fdt_wrapper_setprop(const void *devp, const char *name,
95			       const void *buf, const int len)
96{
97	int rc;
98
99	rc = fdt_setprop(fdt, devp_offset(devp), name, buf, len);
100	if (rc == -FDT_ERR_NOSPACE) {
101		expand_buf(len + 16);
102		rc = fdt_setprop(fdt, devp_offset(devp), name, buf, len);
103	}
104
105	return check_err(rc);
106}
107
108static int fdt_wrapper_del_node(const void *devp)
109{
110	return fdt_del_node(fdt, devp_offset(devp));
111}
112
113static void *fdt_wrapper_get_parent(const void *devp)
114{
115	return offset_devp(fdt_parent_offset(fdt, devp_offset(devp)));
116}
117
118static void *fdt_wrapper_create_node(const void *devp, const char *name)
119{
120	int offset;
121
122	offset = fdt_add_subnode(fdt, devp_offset(devp), name);
123	if (offset == -FDT_ERR_NOSPACE) {
124		expand_buf(strlen(name) + 16);
125		offset = fdt_add_subnode(fdt, devp_offset(devp), name);
126	}
127
128	return offset_devp(offset);
129}
130
131static void *fdt_wrapper_find_node_by_prop_value(const void *prev,
132						 const char *name,
133						 const char *val,
134						 int len)
135{
136	int offset = fdt_node_offset_by_prop_value(fdt, devp_offset_find(prev),
137	                                           name, val, len);
138	return offset_devp(offset);
139}
140
141static void *fdt_wrapper_find_node_by_compatible(const void *prev,
142						 const char *val)
143{
144	int offset = fdt_node_offset_by_compatible(fdt, devp_offset_find(prev),
145	                                           val);
146	return offset_devp(offset);
147}
148
149static char *fdt_wrapper_get_path(const void *devp, char *buf, int len)
150{
151	int rc;
152
153	rc = fdt_get_path(fdt, devp_offset(devp), buf, len);
154	if (check_err(rc))
155		return NULL;
156	return buf;
157}
158
159static unsigned long fdt_wrapper_finalize(void)
160{
161	int rc;
162
163	rc = fdt_pack(fdt);
164	if (rc != 0)
165		fatal("Couldn't pack flat tree: %s\n\r",
166		      fdt_strerror(rc));
167	return (unsigned long)fdt;
168}
169
170void fdt_init(void *blob)
171{
172	int err;
173	int bufsize;
174
175	dt_ops.finddevice = fdt_wrapper_finddevice;
176	dt_ops.getprop = fdt_wrapper_getprop;
177	dt_ops.setprop = fdt_wrapper_setprop;
178	dt_ops.get_parent = fdt_wrapper_get_parent;
179	dt_ops.create_node = fdt_wrapper_create_node;
180	dt_ops.find_node_by_prop_value = fdt_wrapper_find_node_by_prop_value;
181	dt_ops.find_node_by_compatible = fdt_wrapper_find_node_by_compatible;
182	dt_ops.del_node = fdt_wrapper_del_node;
183	dt_ops.get_path = fdt_wrapper_get_path;
184	dt_ops.finalize = fdt_wrapper_finalize;
185
186	/* Make sure the dt blob is the right version and so forth */
187	fdt = blob;
188	bufsize = fdt_totalsize(fdt) + EXPAND_GRANULARITY;
189	buf = malloc(bufsize);
190	if(!buf)
191		fatal("malloc failed. can't relocate the device tree\n\r");
192
193	err = fdt_open_into(fdt, buf, bufsize);
194
195	if (err != 0)
196		fatal("fdt_init(): %s\n\r", fdt_strerror(err));
197
198	fdt = buf;
199}
200