Collabora is Porting Linux's AMD Open-Source Drivers (RADV) to Windows, and CS2 is the First Playable Game

While Linux is known for its strong performance with AMD hardware, users of NVIDIA or Intel GPUs often encounter various issues and suboptimal performance. This is largely due to AMD's long-standing focus on Linux and a dedicated community of users and developers actively enhancing the hardware experience and performance. Now, Collabora has stepped in, deciding to port AMD's open-source RADV drivers, originally for Linux, to Windows.

For AMD GPU owners on Linux, there are two main driver options: 'AMDVLK', AMD's official open-source drivers, and AMDGPU-PRO for professional graphics cards. The alternative comes from the Mesa 3D community drivers, which are open-source and supported by Valve. These are the RADV drivers, known for offering superior performance and stability compared to the official ones.

Porting Linux AMD RADV Open-Source Drivers to Windows

Beyond their performance advantages, RADV drivers receive more frequent updates, incorporating new features and improvements. For instance, January 2024 saw official compatibility with the latest AMD AMF version, and in April 2024, the drivers gained the ability to encode H.264 and H.265 video via Vulkan on Linux. If you've been wishing for these capabilities on Windows, you'll be pleased to know that the Collabora initiative is actively working on porting the Linux RADV drivers to Windows using the Win32 API.

This effort began with Faith Ekstrand's work in 2024, who managed to have RADV send commands to AMD's official drivers through reverse-engineering WDDM 2 on Windows 10. A significant hurdle was Windows' tight coupling between drivers and the kernel, along with its exchange of private data with drivers. To overcome this, Ekstrand developed a tool called 'wddm2-pdd-re', enabling RADV to send tasks to the proprietary kernel. This breakthrough allowed for the successful rendering of a functional 3D model, indicating a successful proof of concept.

Counter-Strike 2 is the First Playable Game, Achieving 162 FPS on an RX 7900 XT

Collabora has built upon this prototype, refining the core idea with several enhancements. Their objectives include improving hardware compatibility across a wider range, reducing overhead, and increasing stability. Furthermore, they have added support for task shaders and tessellation in games, making it possible to render complex graphics.

Indeed, they have successfully run the first game with RADV drivers on Windows: Counter-Strike 2. To enable it, Collabora suggests a simple change to the rendering API using the command-line option '-vulkan'. The accompanying visuals show the game running and appearing quite well, even in a 4:3 aspect ratio (likely due to the display used), achieving an impressive 162 FPS.

However, the process isn't without its challenges. Hardware compatibility remains complex; for example, they encountered difficulties replicating Faith's results using an RX 7900 XT after he had tested with an RX 7800 XT. Additionally, there are ongoing issues with compilers, meaning the drivers are not yet ready for general use. Nevertheless, if Collabora successfully completes the port, we could potentially see performance gains of up to three times in applications that are not heavily GPU-dependent.