[U-Boot] [PATCH] mkimage: fit: spl: Add an optional static offset for external data

[Teddy Reed]

When building a FIT with external data (-E), an SPL may require absolute
positioning for executing the external firmware. To acheive this use the
(-p) switch which will replace the amended "data-offset" with "data-position"
indicating the absolute position of external data.

It is considered an error if the requested absolute position overlaps with the
initial data required for the compact FIT.

Signed-off-by: Teddy Reed <teddy.reed at gmail.com>
Cc: Simon Glass <sjg at chromium.org>
---
 tools/fit_image.c | 19 ++++++++++++++++++-
 tools/imagetool.h |  1 +
 tools/mkimage.c   |  9 ++++++++-
 3 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/tools/fit_image.c b/tools/fit_image.c
index ddefa72..98610bf 100644
--- a/tools/fit_image.c
+++ b/tools/fit_image.c
@@ -417,7 +417,13 @@ static int fit_extract_data(struct image_tool_params *params, const char *fname)
 			ret = -EPERM;
 			goto err_munmap;
 		}
-		fdt_setprop_u32(fdt, node, "data-offset", buf_ptr);
+		if (params->external_offset > 0) {
+			/* An external offset positions the data absolutely. */
+			fdt_setprop_u32(fdt, node, "data-position",
+					params->external_offset + buf_ptr);
+		} else {
+			fdt_setprop_u32(fdt, node, "data-offset", buf_ptr);
+		}
 		fdt_setprop_u32(fdt, node, "data-size", len);
 
 		buf_ptr += (len + 3) & ~3;
@@ -438,6 +444,17 @@ static int fit_extract_data(struct image_tool_params *params, const char *fname)
 		ret = -EIO;
 		goto err;
 	}
+
+	/* Check if an offset for the external data was set. */
+	if (params->external_offset > 0) {
+		if (params->external_offset < new_size) {
+			debug("External offset %x overlaps FIT length %x",
+			      params->external_offset, new_size);
+			ret = -EINVAL;
+			goto err;
+		}
+		new_size = params->external_offset;
+	}
 	if (lseek(fd, new_size, SEEK_SET) < 0) {
 		debug("%s: Failed to seek to end of file: %s\n", __func__,
 		      strerror(errno));
diff --git a/tools/imagetool.h b/tools/imagetool.h
index 24f8f4b..7862fa3 100644
--- a/tools/imagetool.h
+++ b/tools/imagetool.h
@@ -73,6 +73,7 @@ struct image_tool_params {
 	struct content_info *content_head;	/* List of files to include */
 	struct content_info *content_tail;
 	bool external_data;	/* Store data outside the FIT */
+	unsigned int external_offset;	/* Add padding to external data */
 };
 
 /*
diff --git a/tools/mkimage.c b/tools/mkimage.c
index 2931783..85e4781 100644
--- a/tools/mkimage.c
+++ b/tools/mkimage.c
@@ -138,7 +138,7 @@ static void process_args(int argc, char **argv)
 
 	expecting = IH_TYPE_COUNT;	/* Unknown */
 	while ((opt = getopt(argc, argv,
-			     "-a:A:bcC:d:D:e:Ef:Fk:K:ln:O:rR:sT:vVx")) != -1) {
+			     "-a:A:bcC:d:D:e:Ef:Fk:K:ln:p:O:rR:sT:vVx")) != -1) {
 		switch (opt) {
 		case 'a':
 			params.addr = strtoull(optarg, &ptr, 16);
@@ -213,6 +213,13 @@ static void process_args(int argc, char **argv)
 			if (params.os < 0)
 				usage("Invalid operating system");
 			break;
+		case 'p':
+			params.external_offset = strtoull(optarg, &ptr, 16);
+			if (*ptr) {
+				fprintf(stderr, "%s: invalid offset size %s\n",
+					params.cmdname, optarg);
+				exit(EXIT_FAILURE);
+			}
 		case 'r':
 			params.require_keys = 1;
 			break;
-- 
1.9.1