STM32MP15 ECO 5.0.0 Buiding u-boot dtb file missing (custom board)

[debugging]

https://github.com/ARM-software/arm-trusted-firmware/blob/master/docs/plat/stm32mp1.rst
mentions to build u-boot and optee first before TF-A:

Building u-boot raises an error:

Missing stm32mp157a-board-mx-fw-config-optee.dtb file in folder: $FIP_DEPLOYDIR_FWCONF or '$FIP_DEPLOYDIR_ROOT/arm-trusted-firmware/fwconfig'

When building TF-A it fails but it does generated this dtb. After copying the dtb to the FIP_artifact folder, and then running u-boot again , the TF-A builds as well.

Is this how it's supposed to be ?

 

[debugging]

given up on makefile.sdk and just use the make command.