[PATCH v3 8/8] mkimage: fit_image: Add option to make fit header align
kever.yang at rock-chips.com
Mon Mar 30 04:35:38 CEST 2020
On 2020/3/28 上午2:16, Tom Rini wrote:
> On Thu, Mar 26, 2020 at 06:09:16PM +0800, Kever Yang wrote:
>> 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 '-B' to specify the align size in hex for better performance.
>> example usage:
>> ./tools/mkimage -E -f u-boot.its -B 200 u-boot.itb
> OK, so we're taking a hex input, and that's not clear in the
> documentation. The example should also be 0x200 for clarity. In fact,
> being user-space, we need to make this user friendly and sanity check
> the input and if we're going to take hex in, enforce '0x' as a prefix
> even I think. Thanks!
I use hex input because all of other parameters for mkimage tool are using
hex format instead of decimal format.
I will update ot use 0x200.
More information about the U-Boot