Mesa RadeonSI Lands FreeSync / Adaptive-Sync Support That Pair With Linux 4.21
Hitting Mesa 19.0-devel today was the DRI3 loader support around the new DRM Adaptive-Sync / Variable Refresh property and enabling the option for the RadeonSI OpenGL driver. At the moment there is no FreeSync / Adaptive-Sync support for RADV Vulkan. Also, we haven't seen any FreeSync/Adaptive-Sync work on the Wayland front at this time.
To make it completely clear: the Mesa 19.0 code must be used in conjunction with Linux 4.21+, using just one or the other will not yield working support. There are also patches recently merged for FreeSync support within the xf86-video-amdgpu DDX driver.
I'll be firing up some AMD FreeSync support in the days ahead, hopefully over the weekend if time allows. More details on FreeSync and the open-source AMDGPU driver support via this earlier article.