Apple M1/M2 Achieves OpenCL 3.1 Conformance On Asahi Linux With Rusticl

The Khronos Group has listed the first conformant OpenCL 3.1 implementation for Apple M1 and M2 silicon, according to reporting by Phoronix on July 15, 2026. This implementation runs on Asahi Linux using Rusticl, providing a standardized framework for heterogeneous computing and GPU acceleration on Apple’s ARM-based chips within a Linux environment.

OpenCL, or Open Computing Language, is a framework used to write programs that execute across CPUs, GPUs, and other accelerators. Version 3.1 introduces refined memory management and improved support for shared virtual memory, which allows the CPU and GPU to share data more efficiently without constant copying.

Rusticl and the Asahi Linux Implementation

The conformant implementation relies on Rusticl, a Gallium driver for OpenCL written in the Rust programming language. Rusticl is part of the Mesa 3D graphics library project, which aims to provide open-source drivers for a wide array of hardware. By using Rust, the driver minimizes common memory safety bugs that often plague C-based driver development.

Asahi Linux is a community-driven project focused on porting Linux to Apple Silicon. Because Apple does not provide official Linux drivers for the M1 and M2 GPUs, the Asahi team and Mesa contributors must reverse-engineer the hardware to create functional drivers. The achievement of OpenCL 3.1 conformance signifies that the Rusticl implementation for these chips meets the official technical specifications set by the Khronos Group.

Technical Impact for Apple Silicon Users

Standardized OpenCL support allows developers to run compute-heavy workloads on Apple Silicon without relying on Apple’s proprietary Metal framework. This is particularly relevant for scientific computing, video encoding, and machine learning tasks that are designed to be cross-platform.

According to Phoronix, the use of Rusticl ensures that the implementation is integrated directly into the Mesa stack. This means users on supported Linux distributions can access GPU acceleration for OpenCL applications via the same pipeline used for OpenGL or Vulkan graphics.

Context of Open Source Graphics on ARM

The development of these drivers is part of a broader effort to make Apple Silicon a viable target for the Linux ecosystem. While Apple’s hardware is highly optimized for macOS, the lack of official documentation for the GPU makes the creation of a conformant OpenCL driver a significant technical milestone for the open-source community.

Historically, OpenCL implementations for non-standard hardware often suffered from “partial conformance,” where only a subset of the API worked. The Khronos Group’s listing indicates that the M1/M2 implementation on Asahi Linux has passed the required test suites to be recognized as fully conformant to the 3.1 specification.

This development places Asahi Linux in a stronger position for users who require high-performance computing (HPC) tools on portable ARM hardware. By adhering to the OpenCL 3.1 standard, the implementation ensures that software written for other conformant devices should, in theory, run on Apple Silicon under Linux with minimal modification.