2 * Linksys boot counter reset code for mtd
4 * Copyright (C) 2013 Jonas Gorski <jogo@openwrt.org>
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License v2
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
32 #include <sys/ioctl.h>
33 #include <mtd/mtd-user.h>
37 #define BOOTCOUNT_MAGIC 0x20110811
45 static char page[2048];
47 int mtd_resetbc(const char *mtd)
49 struct mtd_info_user mtd_info;
50 struct bootcounter *curr = (struct bootcounter *)page;
57 fd = mtd_check_open(mtd);
59 if (ioctl(fd, MEMGETINFO, &mtd_info) < 0) {
60 fprintf(stderr, "failed to get mtd info!\n");
64 num_bc = mtd_info.size / mtd_info.writesize;
66 for (i = 0; i < num_bc; i++) {
67 pread(fd, curr, sizeof(*curr), i * mtd_info.writesize);
69 if (curr->magic != BOOTCOUNT_MAGIC && curr->magic != 0xffffffff) {
70 fprintf(stderr, "unexpected magic %08x, bailing out\n", curr->magic);
74 if (curr->magic == 0xffffffff)
77 last_count = curr->count;
80 /* no need to do writes when last boot count is already 0 */
86 struct erase_info_user erase_info;
88 erase_info.length = mtd_info.size;
91 ret = ioctl(fd, MEMERASE, &erase_info);
93 fprintf(stderr, "failed to erase block: %i\n", ret);
100 memset(curr, 0xff, mtd_info.writesize);
102 curr->magic = BOOTCOUNT_MAGIC;
104 curr->checksum = BOOTCOUNT_MAGIC;
106 ret = pwrite(fd, curr, mtd_info.writesize, i * mtd_info.writesize);
108 fprintf(stderr, "failed to write: %i\n", ret);