Re: [PATCH v2] dt-bindings: media: Add sram-size Property for Wave5

From: Krzysztof Kozlowski
Date: Fri Feb 02 2024 - 05:47:52 EST


On 01/02/2024 19:42, Brandon Brnich wrote:
> Wave521c has capability to use SRAM carveout to store reference data with
> purpose of reducing memory bandwidth. To properly use this pool, the driver
> expects to have an sram and sram-size node. Without sram-size node, driver
> will default value to zero, making sram node irrelevant.

I am sorry, but what driver expects should not be rationale for new
property. This justification suggests clearly it is not a property for DT.

>
> Signed-off-by: Brandon Brnich <b-brnich@xxxxxx>
> ---

This is v2, so where is the changelog?

> Documentation/devicetree/bindings/media/cnm,wave521c.yaml | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/media/cnm,wave521c.yaml b/Documentation/devicetree/bindings/media/cnm,wave521c.yaml
> index 6a11c1d11fb5..ea5469eb38f9 100644
> --- a/Documentation/devicetree/bindings/media/cnm,wave521c.yaml
> +++ b/Documentation/devicetree/bindings/media/cnm,wave521c.yaml
> @@ -43,6 +43,12 @@ properties:
> storing it on DMA memory. It is mainly used for the purpose of reducing
> bandwidth.
>
> + sram-size:

Does not look like standard property. You would need vendor prefix or is
it documented anywhere already?

> + $ref: /schemas/types.yaml#/definitions/uint32
> + description:
> + SRAM size reserved for VPU operations. If not specified, size will default
> + to zero.

Lack of sram property means 0, doesn't it?

> +
> required:
> - compatible
> - reg
> @@ -58,4 +64,5 @@ examples:
> clocks = <&clks 42>;
> interrupts = <42>;
> sram = <&sram>;
> + sram-size = <0x1234>;

Was this patch tested? Since nothing changed from v1, I assume it also
fails.

> };

Best regards,
Krzysztof