[PATCH] mkimage: fit_image: Make fit header and data align to 512

[Kever Yang]

The image is usually stored in block device like emmc, SD card, make the
offset of image data aligned to block(512 byte) can avoid data copy
during boot process.
eg. SPL boot from FIT image with external data:
- SPL read the first block of FIT image, and then parse the header;
- SPL read image data separately;
- The first image offset is the base_offset which is the header size;
- The second image offset is just after the first image;
- If the offset of imge does not aligned, SPL will do memcpy;
The header size is a ramdon number, which is very possible not aligned, so
add align for FIT header and image data for better performance.

SPI device do not need to enable this feature.

Signed-off-by: Kever Yang <kever.yang at rock-chips.com>
---

 doc/uImage.FIT/source_file_format.txt |  5 +++++
 tools/fit_image.c                     | 16 +++++++++++-----
 tools/imagetool.h                     |  1 +
 tools/mkimage.c                       |  8 ++++++--
 4 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/doc/uImage.FIT/source_file_format.txt b/doc/uImage.FIT/source_file_format.txt
index 18d2aedcb7..50679c4b24 100644
--- a/doc/uImage.FIT/source_file_format.txt
+++ b/doc/uImage.FIT/source_file_format.txt
@@ -304,6 +304,11 @@ Normal kernel FIT image has data embedded within FIT structure. U-Boot image
 for SPL boot has external data. Existence of 'data-offset' can be used to
 identify which format is used.
 
+For FIT image with external data, it would be better to align each blob of data
+to block(512 byte) for block device, so that we don't need to do the copy when
+read the image data in SPL. Pass '-B' to mkimage to align the FIT structure and
+data to 512 byte.
+
 9) Examples
 -----------
 
diff --git a/tools/fit_image.c b/tools/fit_image.c
index 6aa4b1c733..4aeaf39536 100644
--- a/tools/fit_image.c
+++ b/tools/fit_image.c
@@ -431,7 +431,7 @@ static int fit_extract_data(struct image_tool_params *params, const char *fname)
 	fit_size = fdt_totalsize(fdt);
 
 	/* Allocate space to hold the image data we will extract */
-	buf = malloc(fit_size);
+	buf = malloc(fit_size + 2048);
 	if (!buf) {
 		ret = -ENOMEM;
 		goto err_munmap;
@@ -471,17 +471,23 @@ static int fit_extract_data(struct image_tool_params *params, const char *fname)
 					buf_ptr);
 		}
 		fdt_setprop_u32(fdt, node, FIT_DATA_SIZE_PROP, len);
-
-		buf_ptr += (len + 3) & ~3;
+		if (params->bflag)
+			buf_ptr += (len + 511) & ~511;
+		else
+			buf_ptr += (len + 3) & ~3;
 	}
 
 	/* Pack the FDT and place the data after it */
 	fdt_pack(fdt);
 
+	new_size = fdt_totalsize(fdt);
+	if (params->bflag)
+		new_size = (new_size + 511) & ~511;
+	else
+		new_size = (new_size + 3) & ~3;
+	fdt_set_totalsize(fdt, new_size);
 	debug("Size reduced from %x to %x\n", fit_size, fdt_totalsize(fdt));
 	debug("External data size %x\n", buf_ptr);
-	new_size = fdt_totalsize(fdt);
-	new_size = (new_size + 3) & ~3;
 	munmap(fdt, sbuf.st_size);
 
 	if (ftruncate(fd, new_size)) {
diff --git a/tools/imagetool.h b/tools/imagetool.h
index e1c778b0df..e098cb41cc 100644
--- a/tools/imagetool.h
+++ b/tools/imagetool.h
@@ -40,6 +40,7 @@ struct content_info {
  * type specific functions
  */
 struct image_tool_params {
+	int bflag;
 	int dflag;
 	int eflag;
 	int fflag;
diff --git a/tools/mkimage.c b/tools/mkimage.c
index 5f51d2cc89..03b357f869 100644
--- a/tools/mkimage.c
+++ b/tools/mkimage.c
@@ -97,8 +97,9 @@ static void usage(const char *msg)
 		"          -i => input filename for ramdisk file\n");
 #ifdef CONFIG_FIT_SIGNATURE
 	fprintf(stderr,
-		"Signing / verified boot options: [-E] [-k keydir] [-K dtb] [ -c <comment>] [-p addr] [-r] [-N engine]\n"
+		"Signing / verified boot options: [-E] [-B] [-k keydir] [-K dtb] [ -c <comment>] [-p addr] [-r] [-N engine]\n"
 		"          -E => place data outside of the FIT structure\n"
+		"          -B => truncate FIT structure and header to block\n"
 		"          -k => set directory containing private keys\n"
 		"          -K => write public keys to this .dtb file\n"
 		"          -c => add comment in signature node\n"
@@ -143,7 +144,7 @@ static void process_args(int argc, char **argv)
 	int opt;
 
 	while ((opt = getopt(argc, argv,
-			     "a:A: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:qsT:vVx")) != -1) {
 		switch (opt) {
 		case 'a':
 			params.addr = strtoull(optarg, &ptr, 16);
@@ -168,6 +169,9 @@ static void process_args(int argc, char **argv)
 				exit(EXIT_FAILURE);
 			}
 			break;
+		case 'B':
+			params.bflag = optarg;
+			break;
 		case 'c':
 			params.comment = optarg;
 			break;
-- 
2.17.1