Timeout with USB-C video adapter

[Andy Pont]

Jani wrote...

>Does it work all right with the stock UEFI boot, and you're only seeing
>issues with coreboot?
With the stock UEFI solution (AMI) the USB-C HDMI adapters work booting 
from the same Ubuntu disk.  Interestingly, they don’t work under Windows 
11 with the AMI firmware so I’m not convinced their implementation is 
correct either.

>Is /sys/kernel/debug/dri/0/i915_vbt the same for both?
Yes, the VBT file built into the coreboot firmware is the one I 
extracted from /sys/kernel/debug/dri/0/i915_vbt having booted into 
Ubuntu.

I’ll raise it as a bug (albeit I don’t think it is the driver at fault).

-Andy.