1 /*
2 * libfdt - Flat Device Tree manipulation
3 * Copyright (C) 2006 David Gibson, IBM Corporation.
4 *
5 * libfdt is dual licensed: you can use it either under the terms of
6 * the GPL, or the BSD license, at your option.
7 *
8 * a) 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,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public
19 * License along with this library; if not, write to the Free
20 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
21 * MA 02110-1301 USA
22 *
23 * Alternatively,
24 *
25 * b) Redistribution and use in source and binary forms, with or
26 * without modification, are permitted provided that the following
27 * conditions are met:
28 *
29 * 1. Redistributions of source code must retain the above
30 * copyright notice, this list of conditions and the following
31 * disclaimer.
32 * 2. Redistributions in binary form must reproduce the above
33 * copyright notice, this list of conditions and the following
34 * disclaimer in the documentation and/or other materials
35 * provided with the distribution.
36 *
37 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
38 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
39 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
40 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
41 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
42 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
43 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
44 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
45 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
46 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
47 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
48 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
49 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
50 */
51 #include "libfdt_env.h"
52
53 #include <fdt.h>
54 #include <libfdt.h>
55
56 #include "libfdt_internal.h"
57
_fdt_sw_check_header(void * fdt)58 static int _fdt_sw_check_header(void *fdt)
59 {
60 if (fdt_magic(fdt) != FDT_SW_MAGIC)
61 return -FDT_ERR_BADMAGIC;
62 /* FIXME: should check more details about the header state */
63 return 0;
64 }
65
66 #define FDT_SW_CHECK_HEADER(fdt) \
67 { \
68 int err; \
69 if ((err = _fdt_sw_check_header(fdt)) != 0) \
70 return err; \
71 }
72
_fdt_grab_space(void * fdt,size_t len)73 static void *_fdt_grab_space(void *fdt, size_t len)
74 {
75 int offset = fdt_size_dt_struct(fdt);
76 int spaceleft;
77
78 spaceleft = fdt_totalsize(fdt) - fdt_off_dt_struct(fdt)
79 - fdt_size_dt_strings(fdt);
80
81 if ((offset + len < offset) || (offset + len > spaceleft))
82 return NULL;
83
84 fdt_set_size_dt_struct(fdt, offset + len);
85 return _fdt_offset_ptr_w(fdt, offset);
86 }
87
fdt_create(void * buf,int bufsize)88 int fdt_create(void *buf, int bufsize)
89 {
90 void *fdt = buf;
91
92 if (bufsize < sizeof(struct fdt_header))
93 return -FDT_ERR_NOSPACE;
94
95 memset(buf, 0, bufsize);
96
97 fdt_set_magic(fdt, FDT_SW_MAGIC);
98 fdt_set_version(fdt, FDT_LAST_SUPPORTED_VERSION);
99 fdt_set_last_comp_version(fdt, FDT_FIRST_SUPPORTED_VERSION);
100 fdt_set_totalsize(fdt, bufsize);
101
102 fdt_set_off_mem_rsvmap(fdt, FDT_ALIGN(sizeof(struct fdt_header),
103 sizeof(struct fdt_reserve_entry)));
104 fdt_set_off_dt_struct(fdt, fdt_off_mem_rsvmap(fdt));
105 fdt_set_off_dt_strings(fdt, bufsize);
106
107 return 0;
108 }
109
fdt_add_reservemap_entry(void * fdt,uint64_t addr,uint64_t size)110 int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size)
111 {
112 struct fdt_reserve_entry *re;
113 int offset;
114
115 FDT_SW_CHECK_HEADER(fdt);
116
117 if (fdt_size_dt_struct(fdt))
118 return -FDT_ERR_BADSTATE;
119
120 offset = fdt_off_dt_struct(fdt);
121 if ((offset + sizeof(*re)) > fdt_totalsize(fdt))
122 return -FDT_ERR_NOSPACE;
123
124 re = (struct fdt_reserve_entry *)((char *)fdt + offset);
125 re->address = cpu_to_fdt64(addr);
126 re->size = cpu_to_fdt64(size);
127
128 fdt_set_off_dt_struct(fdt, offset + sizeof(*re));
129
130 return 0;
131 }
132
fdt_finish_reservemap(void * fdt)133 int fdt_finish_reservemap(void *fdt)
134 {
135 return fdt_add_reservemap_entry(fdt, 0, 0);
136 }
137
fdt_begin_node(void * fdt,const char * name)138 int fdt_begin_node(void *fdt, const char *name)
139 {
140 struct fdt_node_header *nh;
141 int namelen = strlen(name) + 1;
142
143 FDT_SW_CHECK_HEADER(fdt);
144
145 nh = _fdt_grab_space(fdt, sizeof(*nh) + FDT_TAGALIGN(namelen));
146 if (! nh)
147 return -FDT_ERR_NOSPACE;
148
149 nh->tag = cpu_to_fdt32(FDT_BEGIN_NODE);
150 memcpy(nh->name, name, namelen);
151 return 0;
152 }
153
fdt_end_node(void * fdt)154 int fdt_end_node(void *fdt)
155 {
156 uint32_t *en;
157
158 FDT_SW_CHECK_HEADER(fdt);
159
160 en = _fdt_grab_space(fdt, FDT_TAGSIZE);
161 if (! en)
162 return -FDT_ERR_NOSPACE;
163
164 *en = cpu_to_fdt32(FDT_END_NODE);
165 return 0;
166 }
167
_fdt_find_add_string(void * fdt,const char * s)168 static int _fdt_find_add_string(void *fdt, const char *s)
169 {
170 char *strtab = (char *)fdt + fdt_totalsize(fdt);
171 const char *p;
172 int strtabsize = fdt_size_dt_strings(fdt);
173 int len = strlen(s) + 1;
174 int struct_top, offset;
175
176 p = _fdt_find_string(strtab - strtabsize, strtabsize, s);
177 if (p)
178 return p - strtab;
179
180 /* Add it */
181 offset = -strtabsize - len;
182 struct_top = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt);
183 if (fdt_totalsize(fdt) + offset < struct_top)
184 return 0; /* no more room :( */
185
186 memcpy(strtab + offset, s, len);
187 fdt_set_size_dt_strings(fdt, strtabsize + len);
188 return offset;
189 }
190
fdt_property(void * fdt,const char * name,const void * val,int len)191 int fdt_property(void *fdt, const char *name, const void *val, int len)
192 {
193 struct fdt_property *prop;
194 int nameoff;
195
196 FDT_SW_CHECK_HEADER(fdt);
197
198 nameoff = _fdt_find_add_string(fdt, name);
199 if (nameoff == 0)
200 return -FDT_ERR_NOSPACE;
201
202 prop = _fdt_grab_space(fdt, sizeof(*prop) + FDT_TAGALIGN(len));
203 if (! prop)
204 return -FDT_ERR_NOSPACE;
205
206 prop->tag = cpu_to_fdt32(FDT_PROP);
207 prop->nameoff = cpu_to_fdt32(nameoff);
208 prop->len = cpu_to_fdt32(len);
209 memcpy(prop->data, val, len);
210 return 0;
211 }
212
fdt_finish(void * fdt)213 int fdt_finish(void *fdt)
214 {
215 char *p = (char *)fdt;
216 uint32_t *end;
217 int oldstroffset, newstroffset;
218 uint32_t tag;
219 int offset, nextoffset;
220
221 FDT_SW_CHECK_HEADER(fdt);
222
223 /* Add terminator */
224 end = _fdt_grab_space(fdt, sizeof(*end));
225 if (! end)
226 return -FDT_ERR_NOSPACE;
227 *end = cpu_to_fdt32(FDT_END);
228
229 /* Relocate the string table */
230 oldstroffset = fdt_totalsize(fdt) - fdt_size_dt_strings(fdt);
231 newstroffset = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt);
232 memmove(p + newstroffset, p + oldstroffset, fdt_size_dt_strings(fdt));
233 fdt_set_off_dt_strings(fdt, newstroffset);
234
235 /* Walk the structure, correcting string offsets */
236 offset = 0;
237 while ((tag = fdt_next_tag(fdt, offset, &nextoffset)) != FDT_END) {
238 if (tag == FDT_PROP) {
239 struct fdt_property *prop =
240 _fdt_offset_ptr_w(fdt, offset);
241 int nameoff;
242
243 nameoff = fdt32_to_cpu(prop->nameoff);
244 nameoff += fdt_size_dt_strings(fdt);
245 prop->nameoff = cpu_to_fdt32(nameoff);
246 }
247 offset = nextoffset;
248 }
249 if (nextoffset < 0)
250 return nextoffset;
251
252 /* Finally, adjust the header */
253 fdt_set_totalsize(fdt, newstroffset + fdt_size_dt_strings(fdt));
254 fdt_set_magic(fdt, FDT_MAGIC);
255 return 0;
256 }
257