Michael Larabel, Phoronix reports: One of the limitations of AMD's open source Linux graphics driver was its inability to implement HDMI 2.1+ functionality based on legal requirements by the HDMI Forum. AMD engineers have been working with the HDMI Forum to come up with a solution that would allow open source Linux kernel drivers to provide HDMI 2.1+ functionality, but for now that effort has ended and failed. It seems to have ended. For 3 years now there have been bug reports saying that 4K @ 120Hz is not available via his HDMI 2.1 in AMD Linux drivers. Similarly, even with his AMD graphics driver on Linux he has bug reports such as 5K @ 240Hz is not possible.
As we covered in 2021, the HDMI Forum's closure of access to public specifications is having a negative impact on open source support. AMD and the X.Org Foundation have been working with the HDMI Forum to devise a solution that can provide an open source implementation of the currently private HDMI specification. AMD Linux engineers have spent months with the legal team evaluating all HDMI features to determine if and how they can be exposed with open source drivers. AMD had the code working internally, but for the past few months he was waiting for approval from the HDMI forum. Unfortunately, the HDMI Forum rejected AMD's request for open source driver support.
