blob: 9fa4a94d83c3415102df278f7d63b43b7ab493cb [file] [log] [blame]
Antonio Nino Diazb2db96f2018-10-19 00:56:54 +01001/*
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
58static 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 */
80static 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 */
106static 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
129static 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
144int 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
167int 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
203int 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
223int 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
234int 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
251int 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
265static 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
288int 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
310int 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
322int 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}