I have usb display with touch support and trying to connect it to Khadas VIM3 with Ubuntu 5.7.0 via USB.
If display is not connected, system is booting properly. When display is connected, Khadas is stuck in infinite reboot loop with following error:
yes ! mainline uboot have some problems with some USB devices (for example your situation )
SOLUTION: remove problematic usb device before bootup device - and plugin after
UPDATE: i will try check last uboot updates - may be already was fixed
UPDATE: i will upload new mainline uboot very soon - which have some additional option for ignore usb device (for example its will be usefull in your situation)