AMD Prepares Linux Driver Support For USB4 DP Tunneling
The newest patch series by AMD open-source Linux graphics driver engineers worth mentioning is around USB4 DisplayPort tunneling support for next-generation AMD hardware supporting USB4 connectivity.
The USB4 specification allows for tunneling of DisplayPort 1.4 (as well as DisplayPort 2.0 Alternate Mode, but not the focus of today's patch work) and that is what this new AMDGPU driver work is about for handling DP over USB4 connections.
Right now AMD doesn't support USB4 by current-generation hardware but that is changing... There has been rumors of AMD Ryzen 6000 mobile "Rembrandt" processors supporting USB4. Indeed, with these patches one of them mentions "Yellow Carp" with that being the Linux codename for what is believed to be Rembrandt. So for next-generation AMD laptops there should be USB4 support available as expected.
AMD has been working on the Yellow Carp support openly since this summer and it's good to see them branching out on other improvements like now getting USB4 DisplayPort tunneling in place.
The initial USB4 DP tunneling bring-up for the AMDGPU kernel graphics driver is just under two thousand lines of code and for now is on the mailing list. We'll see if it's reviewed and ready in time for the 5.16 cycle.