diff --git a/tools/patch-image/src/patch-dtb.c b/tools/patch-image/src/patch-dtb.c
new file mode 100644
index 0000000..a94da3f
--- /dev/null
+++ b/tools/patch-image/src/patch-dtb.c
@@ -0,0 +1,103 @@
+/*
+ * patch-dtb.c - patch a dtb into an image
+ *
+ * Copyright (C) 2006 Felix Fietkau <nbd@nbd.name>
+ * Copyright (C) 2012 John Crispin <blogic@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * based on patch-cmdline.c
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <string.h>
+
+#define DTB_MAX	(16 * 1024)
+
+int main(int argc, char **argv)
+{
+	int fd, fddtb, found = 0, len, ret = -1;
+	char *ptr, *ptrdtb, *p;
+	struct stat s;
+	unsigned int search_space , dtb_max_size;
+
+	if (argc <= 2 || argc > 4) {
+		fprintf(stderr, "Usage: %s <file> <dtb> [size]\n", argv[0]);
+		goto err1;
+	} else if (argc == 3) {
+		fprintf(stdout, "DT size used is default of 16KB\n");
+		search_space = dtb_max_size = DTB_MAX;
+	} else {
+		search_space = dtb_max_size = atoi(argv[3]);
+	}
+
+	if (stat(argv[2], &s)) {
+		fprintf(stderr, "DTB not found\n");
+		goto err1;
+	}
+
+	len = s.st_size;
+	if (len + 8 > dtb_max_size) {
+		fprintf(stderr, "DTB too big\n");
+		goto err1;
+	}
+
+        if (((fddtb = open(argv[2], O_RDONLY)) < 0) ||
+		(ptrdtb = (char *) mmap(0, dtb_max_size, PROT_READ, MAP_SHARED, fddtb, 0)) == (void *) (-1)) {
+		fprintf(stderr, "Could not open DTB");
+		goto err2;
+	}
+
+	if (((fd = open(argv[1], O_RDWR)) < 0) ||
+		(ptr = (char *) mmap(0, search_space + dtb_max_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0)) == (void *) (-1)) {
+		fprintf(stderr, "Could not open kernel image");
+		goto err3;
+	}
+
+	for (p = ptr; p < (ptr + search_space); p += 4) {
+		if (memcmp(p, "OWRTDTB:", 8) == 0) {
+			found = 1;
+			p += 8;
+			break;
+		}
+	}
+	if (!found) {
+		fprintf(stderr, "DTB marker not found!\n");
+		goto err4;
+	}
+
+	memset(p, 0, dtb_max_size - 8);
+	memcpy(p, ptrdtb, len);
+	msync(p, len, MS_SYNC|MS_INVALIDATE);
+	ret = 0;
+
+err4:
+	munmap((void *) ptr, len);
+err3:
+	if (fd > 0)
+		close(fd);
+	munmap((void *) ptrdtb, len);
+err2:
+	if (fddtb > 0)
+		close(fddtb);
+err1:
+	return ret;
+}