Adding configuration options to uboot in mender & yocto combination

Hi,

I’m currently attempting to add secure boot (hab) support on the coral dev board with yocto.

I’ve got the yocto build with mender running on the coral board setup according to these instructions: mender hub link

However what I’m attempting to do requires setting some parameters into the uboot defconfig. For example:
CONFIG_SECURE_BOOT=y

I’ve attempted to create a patch into the meta-coral layer to modify the defconfig file, but I’ve not yet been succesful. What I’ve tried is to clone google’s corresponding uboot repository (here) And modifying the board specific defconfig file (this should be under configs/mx8mq_phanbell_defconfig)

After that I generated a git diff patch and added that next to the 3 patches defined in the meta-coral layer. More specifically meta-coral/meta-coral-bsp/recipes-bsp/uboot/uboot-coral_2017.03.bb.

I also had to add PATCHTOOL=“git” into that file above the SRC_URI, otherwise the build would not go through.

However after rebuilding the system image & flashing the bootloader & os into the dev board, it still seems that none of the secure boot related features are available (hab_status in uboot console etc.)

Should patching the uboot configuration be done in some different way, or am I just doing something wrong here?