Comment # 35 on bug 1203748 from Stefan Dirsch

Backup is done. Unfortunately I needed to notice that BIOS updates via
fwupdmgr/fwupdate only work in UEFI mode. But I installed in CSM mode. :-( I
tried to switch in BIOS to UEFI mode, but this that my installed system can't
be booted at all - as I expected. :-(

fwupdate does not work in CSM mode (as fwupdmgr, see comment#32)

linux-3j75:/tmp/tmp # ls
N1QET96W.cab  N1QHT54W.cab
linux-3j75:/tmp/tmp # fwupdate -l
failed: no volumes of type c12a7328-f81f-11d2-ba4b-00a0c93ec93b: no volumes of
type ebd0a0a2-b9e5-4433-87c0-68b6b72699c7

https://bugzilla.redhat.com/show_bug.cgi?id=1904779

I'm not aware of any other means to update the BIOS.

If I ever will reinstall my system, I will switch to UEFI mode first to update
the BIOS. For the time being I need to live with that issue. Thanks a lot for
investigation and all the hints. Learned a lot! I will reassign the bug to
myself, so you no longer need to think about it. Feel free to "unsubscribe"
from it.