[PATCH v3 4/7] dt-bindings: timer: Add RISC-V ACLINT mtimer bindings

[Krzysztof Kozlowski]

On Mon, Nov 09, 2026 at 03:40:44PM +1030, Joel Stanley wrote:
> Document the RISC-V ACLINT mtimer and mtimecmp hardware, as described
> by the riscv-aclint specification, commit 4e570bfd3201f2 [2].
> 
> Multiple vendors are shipping silicon with the hardware as described
> by the specification, which was abandoned[1] as a standalone spec at
> v1.0-rc4.  As we have multiple instances of hardware that implement
> the spec, the widespread implementation of the spec is de facto
> ratification, providing a stationary target for the bindings to document
> and an exception to the policy of not accepting things that are
> pre-ratification.
> 
> [1] https://lists.riscv.org/g/tech-aia/topic/connections_between_aia_and/107177435
> [2] https://github.com/riscvarchive/riscv-aclint/blob/4e570bfd3201f2c09e5afd290b5091526b0f099a/riscv-aclint.adoc
> 
> Signed-off-by: Joel Stanley <joel at jms.id.au>
> ---
> v3:
>   - Rework commit message following discussion at LPC
>   - Add reg-names, rework description, fix example
> ---
>  MAINTAINERS                                   |  1 +
>  .../bindings/timer/riscv,aclint-mtimer.yaml   | 56 +++++++++++++++++++
>  2 files changed, 57 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/timer/riscv,aclint-mtimer.yaml
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 93abbb315065..403875d5932e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -24185,6 +24185,7 @@ S:	Maintained
>  T:	git git://git.kernel.org/pub/scm/linux/kernel/git/tenstorrent/linux.git
>  F:	Documentation/devicetree/bindings/clock/tenstorrent,atlantis-prcm-rcpu.yaml
>  F:	Documentation/devicetree/bindings/riscv/tenstorrent.yaml
> +F:	Documentation/devicetree/bindings/timer/riscv,aclint-mtimer.yaml
>  F:	arch/riscv/boot/dts/tenstorrent/
>  F:	drivers/clk/tenstorrent/
>  F:	drivers/reset/reset-tenstorrent-atlantis.c
> diff --git a/Documentation/devicetree/bindings/timer/riscv,aclint-mtimer.yaml b/Documentation/devicetree/bindings/timer/riscv,aclint-mtimer.yaml
> new file mode 100644
> index 000000000000..e6f3d08d4f93
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/timer/riscv,aclint-mtimer.yaml
> @@ -0,0 +1,56 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/timer/riscv,aclint-mtimer.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: RISC-V Advanced Core Local Interruptor (ACLINT) timer
> +
> +maintainers:
> +  - Joel Stanley <jms at oss.tenstorrent.com>
> +
> +description:
> +  The RISC-V ACLINT specification defines a set of memory mapped devices which
> +  provide timer functionality for each hart on a multi-hart RISC-V platform.
> +  The mtimer device has a single mtime register and one mtimecmp register per
> +  hart. The specification is at https://github.com/riscvarchive/riscv-aclint/
> +
> +properties:
> +  compatible:
> +    items:
> +      - enum:
> +          - tenstorrent,atlantis-aclint-mtimer
> +      - const: riscv,aclint-mtimer
> +
> +  reg:
> +    items:
> +      - description: mtime register
> +      - description: mtimecmp registers
> +
> +  reg-names:
> +    items:
> +      - const: mtime
> +      - const: mtimecmp
> +
> +  interrupts-extended:

Use interrupts. git grep gives basically zero results for such syntax in
the binding.

> +    minItems: 1
> +    maxItems: 4095

Best regards,
Krzysztof