AMD Posts Linux Patches For HDMI 2.1 Auto Low-Latency Mode "ALLM" & VRR

Following AMD posting AMDGPU patches for HDMI 2.1 FRL support after the HDMI 2.1 open-source support was long blocked by the HDMI Forum, as part of working toward a complete HDMI 2.1 implementation in this AMD Linux driver it was followed by HDMI 2.1 Display Stream Compression (DSC) support. Now the latest on the AMDGPU HDMI 2.1 enabling path is enabling Auto Low-Latency Mode (ALLM) as well as HDMI Variable Rate Refresh!

Out today are the patches from AMD for enabling HDMI 2.1's Auto Low-Latency Mode in the AMDGPU Linux driver. HDMI ALLM allows your computer (or game system) to inform the display device to turn on the "Game Mode" to optimize for faster gaming speeds. The intent is on reducing latency and lag for a faster gaming experience with modern TVs / monitors.

With the AMDGPU driver patches, HDMI 2.1 ALLM is enabled when the set content-type is "Game" per user-space requests or when "Gaming-VRR" variable rate refresh is enabled.

The other exciting element is the HDMI 2.1 VRR support with DisplayPort VRR having already been long supported by the AMDGPU driver. Another exciting milestone for Linux gamers with AMD Radeon graphics to finally enjoy HDMI 2.1 VRR.

The patches are now out for review on the mailing list. Time is getting tight though for the DRM-Next cut-off for getting this into the upcoming Linux v7.3 merge window, so we'll see if it makes it for the next kernel cycle during the back half of August or if it will be pulled back until v7.4. In any case great seeing more of the AMDGPU HDMI 2.1 support coming together.