Using USB Mass Storage on AM335X

Hi,

I am working on porting mainline U-Boot to a custom AM335X board that only has eMMC as the boot medium.

I can load U-Boot via serial boot and flash MLO and u-boot.img into the eMMC using DFU. Then the board boots successfully via eMMC.

Now I want to run the "ums" command to be able to mount the eMMC on the host. The problem I am getting is that when I select CONFIG_CMD_USB_MASS_STORAGE=y the board no longer boots.

Does anyone know why selecting CONFIG_CMD_USB_MASS_STORAGE=y causes the board to not boot anymore?

Thanks for your help