I tried to run:
mkimage -O linux -A arm -C none -T flat_dt -d 1021a-twr.dtb uImage.dtb
Can't set header for FIT Image support: Success
The 1021a-twr.dtb was created upon linux kernel build.
I'm not interested in FIT at all.
What am I doing wrong ?
uImage.dtb was created but uboot failed to load it.
There is no need to run mkimage on the dtb file.
Just load it as is.