Re: [PATCH 0/7] Add a DRM driver to support AI Processing Unit (APU)

[Jeffrey Hugo]

On 5/17/2023 8:52 AM, Alexandre Bailon wrote:
> This adds a DRM driver that implements communication between the CPU and an
> APU. The driver target embedded device that usually run inference using some
> prebuilt models. The goal is to provide common infrastructure that could be
> re-used to support many accelerators. Both kernel, userspace and firmware tries
> to use standard and existing to leverage the development and maintenance effort.
> The series implements two platform drivers, one for simulation and another one for
> the mt8183 (compatible with mt8365).

This looks like the 3 existing Accel drivers.  Why is this in DRM?

> For the people interested by the firmware or userspace library,
> the sources are available here:
> https://gitlab.baylibre.com/baylibre/libapu/libapu

I don't see a compiler.  What am I missing?

> The support of APU has to be upstreamed to libdrm.
> Until this is done, you could find the source here:
> https://gitlab.baylibre.com/baylibre/libapu/libdrm/-/tree/abailon/main
>
> The driver for mt8183 depends on this series (which is currently blocked):
> https://patchwork.kernel.org/project/linux-arm-kernel/list/?series=620429
>
> Alexandre Bailon (5):
>    drm: Add support of AI Processor Unit (APU)
>    drm/apu: Add memory allocator
>    drm/apu: Add support of requests
>    drm/apu: Add support of IOMMU
>    dt-bindings: Add bidings for mtk,apu-drm
>
> Julien Stephan (2):
>    drm/apu: allow platform driver to implement their own mmap function
>    drm/apu: Add support for a simulated APU
>
>   .../devicetree/bindings/gpu/mtk,apu-drm.yaml  |  38 ++
>   drivers/gpu/drm/Kconfig                       |   2 +
>   drivers/gpu/drm/Makefile                      |   1 +
>   drivers/gpu/drm/apu/Kconfig                   |  22 +
>   drivers/gpu/drm/apu/Makefile                  |  10 +
>   drivers/gpu/drm/apu/apu_drv.c                 | 282 +++++++++
>   drivers/gpu/drm/apu/apu_gem.c                 | 230 +++++++
>   drivers/gpu/drm/apu/apu_internal.h            | 205 ++++++
>   drivers/gpu/drm/apu/apu_sched.c               | 592 ++++++++++++++++++
>   drivers/gpu/drm/apu/simu_apu.c                | 313 +++++++++
>   include/uapi/drm/apu_drm.h                    |  81 +++

"apu" seems too generic.  We already have 3 "AI processing units" over 
in drivers/accel already...

>   11 files changed, 1776 insertions(+)
>   create mode 100644 Documentation/devicetree/bindings/gpu/mtk,apu-drm.yaml
>   create mode 100644 drivers/gpu/drm/apu/Kconfig
>   create mode 100644 drivers/gpu/drm/apu/Makefile
>   create mode 100644 drivers/gpu/drm/apu/apu_drv.c
>   create mode 100644 drivers/gpu/drm/apu/apu_gem.c
>   create mode 100644 drivers/gpu/drm/apu/apu_internal.h
>   create mode 100644 drivers/gpu/drm/apu/apu_sched.c
>   create mode 100644 drivers/gpu/drm/apu/simu_apu.c
>   create mode 100644 include/uapi/drm/apu_drm.h

I feel like device/driver based documentation in Documentation/ would 
really help in reviews.

-Jeff