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
58static 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
73static 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
88int 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
110int 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
142int 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
165int fdt_finish_reservemap(void *fdt)
166{
167	return fdt_add_reservemap_entry(fdt, 0, 0);
168}
169
170int 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
186int 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
200static 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
223int fdt_property(void *fdt, const char *name, const void *val, int len)
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	memcpy(prop->data, val, len);
242	return 0;
243}
244
245int fdt_finish(void *fdt)
246{
247	char *p = (char *)fdt;
248	fdt32_t *end;
249	int oldstroffset, newstroffset;
250	uint32_t tag;
251	int offset, nextoffset;
252
253	FDT_SW_CHECK_HEADER(fdt);
254
255	/* Add terminator */
256	end = _fdt_grab_space(fdt, sizeof(*end));
257	if (! end)
258		return -FDT_ERR_NOSPACE;
259	*end = cpu_to_fdt32(FDT_END);
260
261	/* Relocate the string table */
262	oldstroffset = fdt_totalsize(fdt) - fdt_size_dt_strings(fdt);
263	newstroffset = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt);
264	memmove(p + newstroffset, p + oldstroffset, fdt_size_dt_strings(fdt));
265	fdt_set_off_dt_strings(fdt, newstroffset);
266
267	/* Walk the structure, correcting string offsets */
268	offset = 0;
269	while ((tag = fdt_next_tag(fdt, offset, &nextoffset)) != FDT_END) {
270		if (tag == FDT_PROP) {
271			struct fdt_property *prop =
272				_fdt_offset_ptr_w(fdt, offset);
273			int nameoff;
274
275			nameoff = fdt32_to_cpu(prop->nameoff);
276			nameoff += fdt_size_dt_strings(fdt);
277			prop->nameoff = cpu_to_fdt32(nameoff);
278		}
279		offset = nextoffset;
280	}
281	if (nextoffset < 0)
282		return nextoffset;
283
284	/* Finally, adjust the header */
285	fdt_set_totalsize(fdt, newstroffset + fdt_size_dt_strings(fdt));
286	fdt_set_magic(fdt, FDT_MAGIC);
287	return 0;
288}
289