This adds the UAPI for the Asahi driver targeting the GPU in the Apple
M1 and M2 series systems on chip. The UAPI design is based on other
modern Vulkan-capable drivers, including Xe and Panthor. Memory
management is based on explicit VM management. Synchronization is
exclusively explicit sync.
This UAPI is validated against our open source Mesa stack, which is
fully conformant to the OpenGL 4.6, OpenGL ES 3.2, OpenCL 3.0, and
Vulkan 1.4 standards. The Vulkan driver supports sparse, exercising the
VM_BIND mechanism.
This patch adds the standalone UAPI header. It is implemented by an open
source DRM driver written in Rust. We fully intend to upstream this
driver when possible. However, as a production graphics driver, it
depends on a significant number of Rust abstractions that will take a
long time to upstream. In the mean time, our userspace is upstream in
Mesa but is not allowed to probe with upstream Mesa as the UAPI is not
yet reviewed and merged in the upstream kernel. Although we ship a
patched Mesa in Fedora Asahi Remix, any containers shipping upstream
Mesa builds are broken for our users, including upstream Flatpak and
Waydroid runtimes. Additionally, it forces us to maintain forks of Mesa
and virglrenderer, which complicates bisects.
The intention in sending out this patch is for this UAPI to be
thoroughly reviewed. Once we as the DRM community are satisfied with the
UAPI, this header lands signifying that the UAPI is stable and must only
be evolved in backwards-compatible ways; it will be the UAPI implemented
in the DRM driver that eventually lands upstream. That promise lets us
enable upstream Mesa, solving all these issues while the upstream Rust
abstractions are developed.
https://github.com/alyssarosenzweig/linux/commits/agx-uapi-v7 contains
the DRM driver implementing this proposed UAPI.
https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33984 contains
the Mesa patches to implement this proposed UAPI.
That Linux and Mesa branch together give a complete graphics/compute
stack on top of this UAPI.
Co-developed-by: Asahi Lina <lina@asahilina.net>
Signed-off-by: Asahi Lina <lina@asahilina.net>
Acked-by: Simona Vetter <simona.vetter@ffwll.ch>
Reviewed-by: Neal Gompa <neal@gompa.dev>
Reviewed-by: Janne Grunau <j@jannau.net>
Reviewed-by: Faith Ekstrand <faith.ekstrand@collabora.com>
Link: https://lore.kernel.org/r/20250408-agx-uapi-v7-1-ad122d4f7324@rosenzweig.io
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
12a2bf6765