On Wed, Oct 15, 2025 at 7:47 PM Rob Herring (Arm) <robh@kernel.org> wrote:
>
> The Arm Ethos-U65/85 NPUs are designed for edge AI inference
> applications[0].
>
> The driver works with Mesa Teflon. A merge request for Ethos support is
> here[1]. The UAPI should also be compatible with the downstream (open
> source) driver stack[2] and Vela compiler though that has not been
> implemented.
>
> Testing so far has been on i.MX93 boards with Ethos-U65 and a FVP model
> with Ethos-U85. More work is needed in mesa for handling U85 command
> stream differences, but that doesn't affect the UABI.
>
> A git tree is here[3].
>
> Rob
>
> [0] https://www.arm.com/products/silicon-ip-cpu?families=ethos%20npus
> [1] https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/36699/
> [2] https://gitlab.arm.com/artificial-intelligence/ethos-u/
> [3] git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git ethos-v4
>
> Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
For the series:
Acked-by: Tomeu Vizoso <tomeu@tomeuvizoso.net>
Regards,
Tomeu
> ---
> Changes in v4:
> - Use bulk clk API
> - Various whitespace fixes mostly due to ethos->ethosu rename
> - Drop error check on dma_set_mask_and_coherent()
> - Drop unnecessary pm_runtime_mark_last_busy() call
> - Move variable declarations out of switch (a riscv/clang build failure)
> - Use lowercase hex in all defines
> - Drop unused ethosu_device.coherent member
> - Add comments on all locks
> - Link to v3: https://lore.kernel.org/r/20250926-ethos-v3-0-6bd24373e4f5@kernel.org
>
> Changes in v3:
> - Rework and improve job submit validation
> - Rename ethos to ethosu. There was an Ethos-Nxx that's unrelated.
> - Add missing init for sched_lock mutex
> - Drop some prints to debug level
> - Fix i.MX93 SRAM accesses (AXI config)
> - Add U85 AXI configuration and test on FVP with U85
> - Print the current cmd value on timeout
> - Link to v2: https://lore.kernel.org/r/20250811-ethos-v2-0-a219fc52a95b@kernel.org
>
> Changes in v2:
> - Rebase on v6.17-rc1 adapting to scheduler changes
> - scheduler: Drop the reset workqueue. According to the scheduler docs,
> we don't need it since we have a single h/w queue.
> - scheduler: Rework the timeout handling to continue running if we are
> making progress. Fixes timeouts on larger jobs.
> - Reset the NPU on resume so it's in a known state
> - Add error handling on clk_get() calls
> - Fix drm_mm splat on module unload. We were missing a put on the
> cmdstream BO in the scheduler clean-up.
> - Fix 0-day report needing explicit bitfield.h include
> - Link to v1: https://lore.kernel.org/r/20250722-ethos-v1-0-cc1c5a0cbbfb@kernel.org
>
> ---
> Rob Herring (Arm) (2):
> dt-bindings: npu: Add Arm Ethos-U65/U85
> accel: Add Arm Ethos-U NPU driver
>
> .../devicetree/bindings/npu/arm,ethos.yaml | 79 +++
> MAINTAINERS | 9 +
> drivers/accel/Kconfig | 1 +
> drivers/accel/Makefile | 1 +
> drivers/accel/ethosu/Kconfig | 10 +
> drivers/accel/ethosu/Makefile | 4 +
> drivers/accel/ethosu/ethosu_device.h | 190 ++++++
> drivers/accel/ethosu/ethosu_drv.c | 418 ++++++++++++
> drivers/accel/ethosu/ethosu_drv.h | 15 +
> drivers/accel/ethosu/ethosu_gem.c | 710 +++++++++++++++++++++
> drivers/accel/ethosu/ethosu_gem.h | 46 ++
> drivers/accel/ethosu/ethosu_job.c | 539 ++++++++++++++++
> drivers/accel/ethosu/ethosu_job.h | 41 ++
> include/uapi/drm/ethosu_accel.h | 261 ++++++++
> 14 files changed, 2324 insertions(+)
> ---
> base-commit: 3a8660878839faadb4f1a6dd72c3179c1df56787
> change-id: 20250715-ethos-3fdd39ef6f19
>
> Best regards,
> --
> Rob Herring (Arm) <robh@kernel.org>
>