2 * patch-dtb.c - patch a dtb into an image
4 * Copyright (C) 2006 Felix Fietkau <nbd@nbd.name>
5 * Copyright (C) 2012 John Crispin <blogic@openwrt.org>
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2
10 * of the License, or (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
21 * based on patch-cmdline.c
33 #define DTB_MAX (16 * 1024)
35 int main(int argc
, char **argv
)
37 int fd
, fddtb
, found
= 0, len
, ret
= -1;
38 char *ptr
, *ptrdtb
, *p
;
40 unsigned int search_space
, dtb_max_size
;
42 if (argc
<= 2 || argc
> 4) {
43 fprintf(stderr
, "Usage: %s <file> <dtb> [size]\n", argv
[0]);
45 } else if (argc
== 3) {
46 fprintf(stdout
, "DT size used is default of 16KB\n");
47 search_space
= dtb_max_size
= DTB_MAX
;
49 search_space
= dtb_max_size
= atoi(argv
[3]);
52 fddtb
= open(argv
[1], O_RDONLY
);
56 if (stat(argv
[2], &s
)) {
57 fprintf(stderr
, "DTB not found\n");
62 if (len
+ 8 > dtb_max_size
) {
63 fprintf(stderr
, "DTB too big\n");
67 if (((fddtb
= open(argv
[2], O_RDONLY
)) < 0) ||
68 (ptrdtb
= (char *) mmap(0, dtb_max_size
, PROT_READ
, MAP_SHARED
, fddtb
, 0)) == (void *) (-1)) {
69 fprintf(stderr
, "Could not open DTB");
73 if (((fd
= open(argv
[1], O_RDWR
)) < 0) ||
74 (ptr
= (char *) mmap(0, search_space
+ dtb_max_size
, PROT_READ
|PROT_WRITE
, MAP_SHARED
, fd
, 0)) == (void *) (-1)) {
75 fprintf(stderr
, "Could not open kernel image");
79 for (p
= ptr
; p
< (ptr
+ search_space
); p
+= 4) {
80 if (memcmp(p
, "OWRTDTB:", 8) == 0) {
87 fprintf(stderr
, "DTB marker not found!\n");
91 memset(p
, 0, dtb_max_size
- 8);
92 memcpy(p
, ptrdtb
, len
);
93 msync(p
, len
, MS_SYNC
|MS_INVALIDATE
);
97 munmap((void *) ptr
, len
);
101 munmap((void *) ptrdtb
, len
);