I have a custom board based on iMX.6ULL. I am trying to flash uboot via mfgtool2 in eMMC. Somehow it gets struck while loading the uboot image. I am taking the uboot image present in the mfgtool2 archive "u-boot-imx6ull14x14ddr3arm2_emmc.imx". Can anyone please help in letting me know what all need to be done to bring up this custom board.