Re: [PATCH v1 02/10] dt-bindings: media: Add MT8188 ImgSys's LARB

[Krzysztof Kozlowski <krzk@kernel.org>]

On 24/05/2025 13:49, Olivia Wen wrote:
> This patch adds support for the MT8188 Image System's Local Arbiter
> (LARB) in the device tree bindings. The LARB is a crucial component in
> MediaTek's ImgSys architecture, responsible for managing memory access
> and arbitration between various hardware modules.
> 
> Signed-off-by: Olivia Wen <olivia.wen@mediatek.com>
> ---
>  .../bindings/media/mediatek,imgsys-larbs.yaml | 75 +++++++++++++++++++

Your patchset wasn't tested, so I won't do full review. Be sure you test
it prior sending. Few nits below:

Please use subject prefixes matching the subsystem. You can get them for
example with `git log --oneline -- DIRECTORY_OR_FILE` on the directory
your patch is touching. For bindings, the preferred subjects are
explained here:
https://www.kernel.org/doc/html/latest/devicetree/bindings/submitting-patches.html#i-for-patch-submitters


>  1 file changed, 75 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/media/mediatek,imgsys-larbs.yaml
> 
> diff --git a/Documentation/devicetree/bindings/media/mediatek,imgsys-larbs.yaml b/Documentation/devicetree/bindings/media/mediatek,imgsys-larbs.yaml
> new file mode 100644
> index 000000000000..d2966c64ddb6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/mediatek,imgsys-larbs.yaml

Filename equal to compatible.

> @@ -0,0 +1,75 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/media/mediatek,imgsys-larbs.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: LARB Information for MediaTek Camera Image System Hardware
> +
> +maintainers:
> +  - Olivia Wen <olivia.wen@mediatek.com>
> +
> +description:
> +  Detailed configuration for MediaTek Camera Image System's Local Arbiter
> +  (LARB) hardware integration.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - mediatek,mt8188-imgsys-larbs
> +
> +  iommus:
> +    minItems: 1
> +    maxItems: 30

This cannot be flexible. List the items, unless it is somehow obvious.


> +
> +  '#address-cells':
> +    const: 2
> +
> +  '#size-cells':
> +    const: 2

These are useless.

> +
> +required:
> +  - compatible
> +  - iommus
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/memory/mediatek,mt8188-memory-port.h>
> +
> +    imgsys-l11b {

Node names should be generic. See also an explanation and list of
examples (not exhaustive) in DT specification:
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation


> +        compatible = "mediatek,mt8188-imgsys-larb";
> +        #address-cells = <2>;
> +        #size-cells = <2>;

Why?

> +        iommus = <&vpp_iommu M4U_PORT_L11B_WPE_RDMA_0>,
> +             <&vpp_iommu M4U_PORT_L11B_WPE_RDMA_1>,

Fix alignment.



Best regards,
Krzysztof