The Mesa RADV driver, the open-source Vulkan implementation that underpins AMD graphics on Linux and powers gaming on the Steam Deck, is being ported to Windows. Valve is sponsoring engineers at Collabora to carry out the early-phase work, which has already reached the point of running Counter-Strike 2 on an AMD GPU under Windows using the fully open-source driver stack.
The core technical challenge is that porting the Linux AMDGPU kernel driver to Windows is out of scope. Instead, the Collabora team is building RADV on top of AMD's proprietary Radeon Software kernel driver, which means reverse engineering undocumented data structures and interfaces in the Windows driver to make RADV talk to it. For long-term viability, the project will need either a stable, documented interface to AMD's Windows kernel module or a shim library that absorbs the breakage between Radeon Software releases.
RADV has been one of the Mesa project's flagship success stories. Valve funds multiple developers working on the driver full-time, and its performance and compatibility gains have been central to Proton's ability to run Windows games on Linux with minimal friction. Bringing RADV to Windows flips that relationship: rather than translating Windows graphics calls for Linux, the same open-source driver code would run natively on both platforms. That could give Valve a consistent, vendor-independent Vulkan layer across SteamOS and Windows, reducing the gap between the two and giving the company less reliance on AMD's proprietary user-space driver.
The experimental code is available on a development branch on GitLab. There is no timeline for when, or whether, this work will land in mainline Mesa.
