[U-Boot] imx7 u-boot nand update from u-boot

Hi,

I'm trying to figure out how it is possible easily update u-boot in nand on custom imx7 board. I can start u-boot using imx_usb tool. I came from ti am33xx world where I simply get u-boot.img from tftp server and store it to beginning of flash (after SPL offset).

According imx7 datasheet for nand boot it is necessary to store FCB + DBBT and other things. It is currently possible only with userspace tool kobs-ng which can save u-boot to nand memory. It is possible to generate such image (with FCB, ...) to be able to update u-boot from u-boot by tftp and some nand write? Or it is enough to just write u-boot.imx to offset 0x400 when u-boot was writen before by kobs-ng and it will work? Many thanks for replies.

BR,

marek