AMD Posts Linux Patches In Preparing For DisplayPort 2.0 Radeon GPU Support
UHBR10 is one of the new data rates / modes of DisplayPort 2.0. With Ultra High Bit Rate (UHBR) 10 there is 10 Gbps per lane to allow 40 Gbps of bandwidth over passive copper cabling. The SST aspect of this patch series is just denoting it's for single stream transport rather than multi-stream transport (MST).
DisplayPort 2.0 additionally supports UHBR 13.5 and UHBR 20 modes but this patch series for the AMDGPU direct rendering manager driver is just in regards to the UHBR 10 mode. UHBR is compliant with VESA's DisplayPort 8K (DP8K) certification. Over DP HBR3, the UHBR 10 mode also allows for 4K @ 144Hz for standard video content and much broader support for HDR content at 4K and above at higher refresh rates than HBR3.
These six patches get the DP 2.0 SST UHBR10 support going after adding some five thousand lines of new code.
DisplayPort 2.0 was announced back in 2019 with a 3x increase to the data bandwidth performance, new power conservation features, and more. So far though the GPU hardware and driver support has been slow to materialize. Similarly, DisplayPort 2.0 monitors have been slow to reach market -- reportedly delayed by the pandemic but could begin appearing in the months ahead.
Due to the timing of these patches, however, it's not likely that they will get queued up for Linux 5.15 but more than likely divert to Linux 5.16. That though should ultimately be fine considering the latest-generation Radeon RX 6000 series supports DisplayPort 1.4. This AMDGPU DC work around DP 2.0 UHBR10 is likely in preparation for next-gen graphics (RDNA3 / Radeon RX 7000 series).