[v3,20/49] mkimage: Allow updating the FIT timestamp

diff --git a/doc/mkimage.1 b/doc/mkimage.1
index 3dcdcedcef..fea5288784 100644
--- a/doc/mkimage.1
+++ b/doc/mkimage.1
@@ -167,6 +167,15 @@  Specifies that keys used to sign the FIT are required. This means that they
 must be verified for the image to boot. Without this option, the verification
 will be optional (useful for testing but not for release).
 
+.TP
+.BI "\-t
+Update the timestamp in the FIT.
+
+Normally the FIT timestamp is created the first time mkimage is run on a FIT,
+when converting the source .its to the binary .fit file. This corresponds to
+using the -f flag. But if the original input to mkimage is a binary file
+(already compiled) then the timestamp is assumed to have been set previously.
+
 .SH EXAMPLES
 
 List image information:
diff --git a/tools/fit_image.c b/tools/fit_image.c
index a082d9386d..df310b53da 100644
--- a/tools/fit_image.c
+++ b/tools/fit_image.c
@@ -53,7 +53,7 @@  static int fit_add_file_data(struct image_tool_params *params, size_t size_inc,
 	}
 
 	/* for first image creation, add a timestamp at offset 0 i.e., root  */
-	if (params->datafile) {
+	if (params->datafile || params->reset_timestamp) {
 		time_t time = imagetool_get_source_date(params->cmdname,
 							sbuf.st_mtime);
 		ret = fit_set_timestamp(ptr, 0, time);
diff --git a/tools/imagetool.h b/tools/imagetool.h
index f54809cd57..acbc48e9be 100644
--- a/tools/imagetool.h
+++ b/tools/imagetool.h
@@ -81,6 +81,7 @@  struct image_tool_params {
 	unsigned int external_offset;	/* Add padding to external data */
 	int bl_len;		/* Block length in byte for external data */
 	const char *engine_id;	/* Engine to use for signing */
+	bool reset_timestamp;	/* Reset the timestamp on an existing image */
 };
 
 /*
diff --git a/tools/mkimage.c b/tools/mkimage.c
index d2cd191787..a7eb4d4360 100644
--- a/tools/mkimage.c
+++ b/tools/mkimage.c
@@ -145,7 +145,7 @@  static void process_args(int argc, char **argv)
 	int opt;
 
 	while ((opt = getopt(argc, argv,
-			     "a:A:b:B:c:C:d:D:e:Ef:Fk:i:K:ln:N:p:O:rR:qsT:vVx")) != -1) {
+		   "a:A:b:B:c:C:d:D:e:Ef:Fk:i:K:ln:N:p:O:rR:qstT:vVx")) != -1) {
 		switch (opt) {
 		case 'a':
 			params.addr = strtoull(optarg, &ptr, 16);
@@ -269,6 +269,9 @@  static void process_args(int argc, char **argv)
 		case 's':
 			params.skipcpy = 1;
 			break;
+		case 't':
+			params.reset_timestamp = 1;
+			break;
 		case 'T':
 			if (strcmp(optarg, "list") == 0) {
 				show_valid_options(IH_TYPE);