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_resize(void * fdt,void * buf,int bufsize)110 int fdt_resize(void *fdt, void *buf, int bufsize)
111 {
112 size_t headsize, tailsize;
113 char *oldtail, *newtail;
114
115 FDT_SW_CHECK_HEADER(fdt);
116
117 headsize = fdt_off_dt_struct(fdt);
118 tailsize = fdt_size_dt_strings(fdt);
119
120 if ((headsize + tailsize) > bufsize)
121 return -FDT_ERR_NOSPACE;
122
123 oldtail = (char *)fdt + fdt_totalsize(fdt) - tailsize;
124 newtail = (char *)buf + bufsize - tailsize;
125
126 /* Two cases to avoid clobbering data if the old and new
127 * buffers partially overlap */
128 if (buf <= fdt) {
129 memmove(buf, fdt, headsize);
130 memmove(newtail, oldtail, tailsize);
131 } else {
132 memmove(newtail, oldtail, tailsize);
133 memmove(buf, fdt, headsize);
134 }
135
136 fdt_set_off_dt_strings(buf, bufsize);
137 fdt_set_totalsize(buf, bufsize);
138
139 return 0;
140 }
141
fdt_add_reservemap_entry(void * fdt,uint64_t addr,uint64_t size)142 int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size)
143 {
144 struct fdt_reserve_entry *re;
145 int offset;
146
147 FDT_SW_CHECK_HEADER(fdt);
148
149 if (fdt_size_dt_struct(fdt))
150 return -FDT_ERR_BADSTATE;
151
152 offset = fdt_off_dt_struct(fdt);
153 if ((offset + sizeof(*re)) > fdt_totalsize(fdt))
154 return -FDT_ERR_NOSPACE;
155
156 re = (struct fdt_reserve_entry *)((char *)fdt + offset);
157 re->address = cpu_to_fdt64(addr);
158 re->size = cpu_to_fdt64(size);
159
160 fdt_set_off_dt_struct(fdt, offset + sizeof(*re));
161
162 return 0;
163 }
164
fdt_finish_reservemap(void * fdt)165 int fdt_finish_reservemap(void *fdt)
166 {
167 return fdt_add_reservemap_entry(fdt, 0, 0);
168 }
169
fdt_begin_node(void * fdt,const char * name)170 int fdt_begin_node(void *fdt, const char *name)
171 {
172 struct fdt_node_header *nh;
173 int namelen = strlen(name) + 1;
174
175 FDT_SW_CHECK_HEADER(fdt);
176
177 nh = fdt_grab_space_(fdt, sizeof(*nh) + FDT_TAGALIGN(namelen));
178 if (! nh)
179 return -FDT_ERR_NOSPACE;
180
181 nh->tag = cpu_to_fdt32(FDT_BEGIN_NODE);
182 memcpy(nh->name, name, namelen);
183 return 0;
184 }
185
fdt_end_node(void * fdt)186 int fdt_end_node(void *fdt)
187 {
188 fdt32_t *en;
189
190 FDT_SW_CHECK_HEADER(fdt);
191
192 en = fdt_grab_space_(fdt, FDT_TAGSIZE);
193 if (! en)
194 return -FDT_ERR_NOSPACE;
195
196 *en = cpu_to_fdt32(FDT_END_NODE);
197 return 0;
198 }
199
fdt_find_add_string_(void * fdt,const char * s)200 static int fdt_find_add_string_(void *fdt, const char *s)
201 {
202 char *strtab = (char *)fdt + fdt_totalsize(fdt);
203 const char *p;
204 int strtabsize = fdt_size_dt_strings(fdt);
205 int len = strlen(s) + 1;
206 int struct_top, offset;
207
208 p = fdt_find_string_(strtab - strtabsize, strtabsize, s);
209 if (p)
210 return p - strtab;
211
212 /* Add it */
213 offset = -strtabsize - len;
214 struct_top = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt);
215 if (fdt_totalsize(fdt) + offset < struct_top)
216 return 0; /* no more room :( */
217
218 memcpy(strtab + offset, s, len);
219 fdt_set_size_dt_strings(fdt, strtabsize + len);
220 return offset;
221 }
222
fdt_property_placeholder(void * fdt,const char * name,int len,void ** valp)223 int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp)
224 {
225 struct fdt_property *prop;
226 int nameoff;
227
228 FDT_SW_CHECK_HEADER(fdt);
229
230 nameoff = fdt_find_add_string_(fdt, name);
231 if (nameoff == 0)
232 return -FDT_ERR_NOSPACE;
233
234 prop = fdt_grab_space_(fdt, sizeof(*prop) + FDT_TAGALIGN(len));
235 if (! prop)
236 return -FDT_ERR_NOSPACE;
237
238 prop->tag = cpu_to_fdt32(FDT_PROP);
239 prop->nameoff = cpu_to_fdt32(nameoff);
240 prop->len = cpu_to_fdt32(len);
241 *valp = prop->data;
242 return 0;
243 }
244
fdt_property(void * fdt,const char * name,const void * val,int len)245 int fdt_property(void *fdt, const char *name, const void *val, int len)
246 {
247 void *ptr;
248 int ret;
249
250 ret = fdt_property_placeholder(fdt, name, len, &ptr);
251 if (ret)
252 return ret;
253 memcpy(ptr, val, len);
254 return 0;
255 }
256
fdt_finish(void * fdt)257 int fdt_finish(void *fdt)
258 {
259 char *p = (char *)fdt;
260 fdt32_t *end;
261 int oldstroffset, newstroffset;
262 uint32_t tag;
263 int offset, nextoffset;
264
265 FDT_SW_CHECK_HEADER(fdt);
266
267 /* Add terminator */
268 end = fdt_grab_space_(fdt, sizeof(*end));
269 if (! end)
270 return -FDT_ERR_NOSPACE;
271 *end = cpu_to_fdt32(FDT_END);
272
273 /* Relocate the string table */
274 oldstroffset = fdt_totalsize(fdt) - fdt_size_dt_strings(fdt);
275 newstroffset = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt);
276 memmove(p + newstroffset, p + oldstroffset, fdt_size_dt_strings(fdt));
277 fdt_set_off_dt_strings(fdt, newstroffset);
278
279 /* Walk the structure, correcting string offsets */
280 offset = 0;
281 while ((tag = fdt_next_tag(fdt, offset, &nextoffset)) != FDT_END) {
282 if (tag == FDT_PROP) {
283 struct fdt_property *prop =
284 fdt_offset_ptr_w_(fdt, offset);
285 int nameoff;
286
287 nameoff = fdt32_to_cpu(prop->nameoff);
288 nameoff += fdt_size_dt_strings(fdt);
289 prop->nameoff = cpu_to_fdt32(nameoff);
290 }
291 offset = nextoffset;
292 }
293 if (nextoffset < 0)
294 return nextoffset;
295
296 /* Finally, adjust the header */
297 fdt_set_totalsize(fdt, newstroffset + fdt_size_dt_strings(fdt));
298 fdt_set_magic(fdt, FDT_MAGIC);
299 return 0;
300 }
301
