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 | |
58 | static int fdt_sw_probe_(void *fdt) |
59 | { |
60 | if (fdt_magic(fdt) == FDT_MAGIC) |
61 | return -FDT_ERR_BADSTATE; |
62 | else if (fdt_magic(fdt) != FDT_SW_MAGIC) |
63 | return -FDT_ERR_BADMAGIC; |
64 | return 0; |
65 | } |
66 | |
67 | #define FDT_SW_PROBE(fdt) \ |
68 | { \ |
69 | int err; \ |
70 | if ((err = fdt_sw_probe_(fdt)) != 0) \ |
71 | return err; \ |
72 | } |
73 | |
74 | /* 'memrsv' state: Initial state after fdt_create() |
75 | * |
76 | * Allowed functions: |
77 | * fdt_add_reservmap_entry() |
78 | * fdt_finish_reservemap() [moves to 'struct' state] |
79 | */ |
80 | static int fdt_sw_probe_memrsv_(void *fdt) |
81 | { |
82 | int err = fdt_sw_probe_(fdt); |
83 | if (err) |
84 | return err; |
85 | |
86 | if (fdt_off_dt_strings(fdt) != 0) |
87 | return -FDT_ERR_BADSTATE; |
88 | return 0; |
89 | } |
90 | |
91 | #define FDT_SW_PROBE_MEMRSV(fdt) \ |
92 | { \ |
93 | int err; \ |
94 | if ((err = fdt_sw_probe_memrsv_(fdt)) != 0) \ |
95 | return err; \ |
96 | } |
97 | |
98 | /* 'struct' state: Enter this state after fdt_finish_reservemap() |
99 | * |
100 | * Allowed functions: |
101 | * fdt_begin_node() |
102 | * fdt_end_node() |
103 | * fdt_property*() |
104 | * fdt_finish() [moves to 'complete' state] |
105 | */ |
106 | static int fdt_sw_probe_struct_(void *fdt) |
107 | { |
108 | int err = fdt_sw_probe_(fdt); |
109 | if (err) |
110 | return err; |
111 | |
112 | if (fdt_off_dt_strings(fdt) != fdt_totalsize(fdt)) |
113 | return -FDT_ERR_BADSTATE; |
114 | return 0; |
115 | } |
116 | |
117 | #define FDT_SW_PROBE_STRUCT(fdt) \ |
118 | { \ |
119 | int err; \ |
120 | if ((err = fdt_sw_probe_struct_(fdt)) != 0) \ |
121 | return err; \ |
122 | } |
123 | |
124 | /* 'complete' state: Enter this state after fdt_finish() |
125 | * |
126 | * Allowed functions: none |
127 | */ |
128 | |
129 | static void *fdt_grab_space_(void *fdt, size_t len) |
130 | { |
131 | int offset = fdt_size_dt_struct(fdt); |
132 | int spaceleft; |
133 | |
134 | spaceleft = fdt_totalsize(fdt) - fdt_off_dt_struct(fdt) |
135 | - fdt_size_dt_strings(fdt); |
136 | |
137 | if ((offset + len < offset) || (offset + len > spaceleft)) |
138 | return NULL; |
139 | |
140 | fdt_set_size_dt_struct(fdt, offset + len); |
141 | return fdt_offset_ptr_w_(fdt, offset); |
142 | } |
143 | |
144 | int fdt_create(void *buf, int bufsize) |
145 | { |
146 | const size_t hdrsize = FDT_ALIGN(sizeof(struct fdt_header), |
147 | sizeof(struct fdt_reserve_entry)); |
148 | void *fdt = buf; |
149 | |
150 | if (bufsize < hdrsize) |
151 | return -FDT_ERR_NOSPACE; |
152 | |
153 | memset(buf, 0, bufsize); |
154 | |
155 | fdt_set_magic(fdt, FDT_SW_MAGIC); |
156 | fdt_set_version(fdt, FDT_LAST_SUPPORTED_VERSION); |
157 | fdt_set_last_comp_version(fdt, FDT_FIRST_SUPPORTED_VERSION); |
158 | fdt_set_totalsize(fdt, bufsize); |
159 | |
160 | fdt_set_off_mem_rsvmap(fdt, hdrsize); |
161 | fdt_set_off_dt_struct(fdt, fdt_off_mem_rsvmap(fdt)); |
162 | fdt_set_off_dt_strings(fdt, 0); |
163 | |
164 | return 0; |
165 | } |
166 | |
167 | int fdt_resize(void *fdt, void *buf, int bufsize) |
168 | { |
169 | size_t headsize, tailsize; |
170 | char *oldtail, *newtail; |
171 | |
172 | FDT_SW_PROBE(fdt); |
173 | |
174 | headsize = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt); |
175 | tailsize = fdt_size_dt_strings(fdt); |
176 | |
177 | if ((headsize + tailsize) > fdt_totalsize(fdt)) |
178 | return -FDT_ERR_INTERNAL; |
179 | |
180 | if ((headsize + tailsize) > bufsize) |
181 | return -FDT_ERR_NOSPACE; |
182 | |
183 | oldtail = (char *)fdt + fdt_totalsize(fdt) - tailsize; |
184 | newtail = (char *)buf + bufsize - tailsize; |
185 | |
186 | /* Two cases to avoid clobbering data if the old and new |
187 | * buffers partially overlap */ |
188 | if (buf <= fdt) { |
189 | memmove(buf, fdt, headsize); |
190 | memmove(newtail, oldtail, tailsize); |
191 | } else { |
192 | memmove(newtail, oldtail, tailsize); |
193 | memmove(buf, fdt, headsize); |
194 | } |
195 | |
196 | fdt_set_totalsize(buf, bufsize); |
197 | if (fdt_off_dt_strings(buf)) |
198 | fdt_set_off_dt_strings(buf, bufsize); |
199 | |
200 | return 0; |
201 | } |
202 | |
203 | int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size) |
204 | { |
205 | struct fdt_reserve_entry *re; |
206 | int offset; |
207 | |
208 | FDT_SW_PROBE_MEMRSV(fdt); |
209 | |
210 | offset = fdt_off_dt_struct(fdt); |
211 | if ((offset + sizeof(*re)) > fdt_totalsize(fdt)) |
212 | return -FDT_ERR_NOSPACE; |
213 | |
214 | re = (struct fdt_reserve_entry *)((char *)fdt + offset); |
215 | re->address = cpu_to_fdt64(addr); |
216 | re->size = cpu_to_fdt64(size); |
217 | |
218 | fdt_set_off_dt_struct(fdt, offset + sizeof(*re)); |
219 | |
220 | return 0; |
221 | } |
222 | |
223 | int fdt_finish_reservemap(void *fdt) |
224 | { |
225 | int err = fdt_add_reservemap_entry(fdt, 0, 0); |
226 | |
227 | if (err) |
228 | return err; |
229 | |
230 | fdt_set_off_dt_strings(fdt, fdt_totalsize(fdt)); |
231 | return 0; |
232 | } |
233 | |
234 | int fdt_begin_node(void *fdt, const char *name) |
235 | { |
236 | struct fdt_node_header *nh; |
237 | int namelen; |
238 | |
239 | FDT_SW_PROBE_STRUCT(fdt); |
240 | |
241 | namelen = strlen(name) + 1; |
242 | nh = fdt_grab_space_(fdt, sizeof(*nh) + FDT_TAGALIGN(namelen)); |
243 | if (! nh) |
244 | return -FDT_ERR_NOSPACE; |
245 | |
246 | nh->tag = cpu_to_fdt32(FDT_BEGIN_NODE); |
247 | memcpy(nh->name, name, namelen); |
248 | return 0; |
249 | } |
250 | |
251 | int fdt_end_node(void *fdt) |
252 | { |
253 | fdt32_t *en; |
254 | |
255 | FDT_SW_PROBE_STRUCT(fdt); |
256 | |
257 | en = fdt_grab_space_(fdt, FDT_TAGSIZE); |
258 | if (! en) |
259 | return -FDT_ERR_NOSPACE; |
260 | |
261 | *en = cpu_to_fdt32(FDT_END_NODE); |
262 | return 0; |
263 | } |
264 | |
265 | static int fdt_find_add_string_(void *fdt, const char *s) |
266 | { |
267 | char *strtab = (char *)fdt + fdt_totalsize(fdt); |
268 | const char *p; |
269 | int strtabsize = fdt_size_dt_strings(fdt); |
270 | int len = strlen(s) + 1; |
271 | int struct_top, offset; |
272 | |
273 | p = fdt_find_string_(strtab - strtabsize, strtabsize, s); |
274 | if (p) |
275 | return p - strtab; |
276 | |
277 | /* Add it */ |
278 | offset = -strtabsize - len; |
279 | struct_top = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt); |
280 | if (fdt_totalsize(fdt) + offset < struct_top) |
281 | return 0; /* no more room :( */ |
282 | |
283 | memcpy(strtab + offset, s, len); |
284 | fdt_set_size_dt_strings(fdt, strtabsize + len); |
285 | return offset; |
286 | } |
287 | |
288 | int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp) |
289 | { |
290 | struct fdt_property *prop; |
291 | int nameoff; |
292 | |
293 | FDT_SW_PROBE_STRUCT(fdt); |
294 | |
295 | nameoff = fdt_find_add_string_(fdt, name); |
296 | if (nameoff == 0) |
297 | return -FDT_ERR_NOSPACE; |
298 | |
299 | prop = fdt_grab_space_(fdt, sizeof(*prop) + FDT_TAGALIGN(len)); |
300 | if (! prop) |
301 | return -FDT_ERR_NOSPACE; |
302 | |
303 | prop->tag = cpu_to_fdt32(FDT_PROP); |
304 | prop->nameoff = cpu_to_fdt32(nameoff); |
305 | prop->len = cpu_to_fdt32(len); |
306 | *valp = prop->data; |
307 | return 0; |
308 | } |
309 | |
310 | int fdt_property(void *fdt, const char *name, const void *val, int len) |
311 | { |
312 | void *ptr; |
313 | int ret; |
314 | |
315 | ret = fdt_property_placeholder(fdt, name, len, &ptr); |
316 | if (ret) |
317 | return ret; |
318 | memcpy(ptr, val, len); |
319 | return 0; |
320 | } |
321 | |
322 | int fdt_finish(void *fdt) |
323 | { |
324 | char *p = (char *)fdt; |
325 | fdt32_t *end; |
326 | int oldstroffset, newstroffset; |
327 | uint32_t tag; |
328 | int offset, nextoffset; |
329 | |
330 | FDT_SW_PROBE_STRUCT(fdt); |
331 | |
332 | /* Add terminator */ |
333 | end = fdt_grab_space_(fdt, sizeof(*end)); |
334 | if (! end) |
335 | return -FDT_ERR_NOSPACE; |
336 | *end = cpu_to_fdt32(FDT_END); |
337 | |
338 | /* Relocate the string table */ |
339 | oldstroffset = fdt_totalsize(fdt) - fdt_size_dt_strings(fdt); |
340 | newstroffset = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt); |
341 | memmove(p + newstroffset, p + oldstroffset, fdt_size_dt_strings(fdt)); |
342 | fdt_set_off_dt_strings(fdt, newstroffset); |
343 | |
344 | /* Walk the structure, correcting string offsets */ |
345 | offset = 0; |
346 | while ((tag = fdt_next_tag(fdt, offset, &nextoffset)) != FDT_END) { |
347 | if (tag == FDT_PROP) { |
348 | struct fdt_property *prop = |
349 | fdt_offset_ptr_w_(fdt, offset); |
350 | int nameoff; |
351 | |
352 | nameoff = fdt32_to_cpu(prop->nameoff); |
353 | nameoff += fdt_size_dt_strings(fdt); |
354 | prop->nameoff = cpu_to_fdt32(nameoff); |
355 | } |
356 | offset = nextoffset; |
357 | } |
358 | if (nextoffset < 0) |
359 | return nextoffset; |
360 | |
361 | /* Finally, adjust the header */ |
362 | fdt_set_totalsize(fdt, newstroffset + fdt_size_dt_strings(fdt)); |
363 | fdt_set_magic(fdt, FDT_MAGIC); |
364 | return 0; |
365 | } |
366 | |