[fedora-arm] u-boot blues

Hi,

So Fedora 34 minimal aarch64 boots and runs pretty good on my rpi4 4GB (great work!).

I have a powered USB 3 hub attached to it, and on that an arduino mega with rflink [1]. When I attach this after booting, it is recognised correctly, but when connected while booting, it runs into a boot-loop:

Others within the domotica community also have this issue and it seems to be related to the use of u-boot [2]. This is also why rapsbian based distros like dietpi boot without issue as they do not use u-boot afaik.

I am not familiar with u-boot at all. Is there a way to exclude this device from the boot device discovery somehow (as I suspect this is where it goes wrong). 

[1] https://www.nodo-shop.nl/nl/rflink-gateway/168-rflink-868-arduino-antenne-usb-kabel.html

[2] https://github.com/home-assistant/operating-system/issues/1011

Thanks!

- Fred