+Mika On Fri, May 20, 2022 at 12:22:50PM +0200, Stefan Hoffmeister wrote: > I am trying to diagnose a problem where I get video output on > Thunderbolt on one DisplayPort, but no output on the second > DisplayPort. > > I would love to turn on all the (kernel-level) logging output that > there is, but do not know how to do that. > > Basically, on a Dell Inspiron 16 Plus (7610) laptop with Thunderbolt > 4, I am running Fedora Linux 36 with kernel 5.17+. > > Connecting that laptop to a Thunderbolt docking station (Intel > Thunderbolt 3 chip inside), > with two screens attached via DisplayPort, I get only one screen up and running. > > I'd like to discover more about this apparent error mode, because > attaching a different TB3 > setup works fine. I am looking for some means to enable logging or to > get debugging insight. > > Generally speaking, I suspect that this specific Dell laptop > (configuration) has some challenges > in the BIOS, and with Thunderbolt in general, but am totally blind to > what is going on. > > This system offers potential for fun, this being a hybrid PRIME > configuration, with an Intel iGPU passing through to an Nvidia dGPU > which seems to be the only wired-up way to get DisplayPort output. -- heikki
