Re: [PATCH RFC v2 1/5] dt-bindings: net: dwmac-meson: use picoseconds for the RGMII RX delay

[Rob Herring <robh@kernel.org>]

On Sun, Nov 15, 2020 at 07:52:06PM +0100, Martin Blumenstingl wrote:
> Amlogic Meson G12A, G12B and SM1 SoCs have a more advanced RGMII RX
> delay register which allows picoseconds precision. Deprecate the old
> "amlogic,rx-delay-ns" in favour of a new "amlogic,rgmii-rx-delay-ps"
> property.
> 
> For older SoCs the only known supported values were 0ns and 2ns. The new
> SoCs have 200ps precision and support RGMII RX delays between 0ps and
> 3000ps.
> 
> While here, also update the description of the RX delay to indicate
> that:
> - with "rgmii" or "rgmii-id" the RX delay should be specified
> - with "rgmii-id" or "rgmii-rxid" the RX delay is added by the PHY so
>   any configuration on the MAC side is ignored
> - with "rmii" the RX delay is not applicable and any configuration is
>   ignored
> 
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> ---
>  .../bindings/net/amlogic,meson-dwmac.yaml     | 61 +++++++++++++++++--
>  1 file changed, 56 insertions(+), 5 deletions(-)

Don't we have common properties for this now?

> 
> diff --git a/Documentation/devicetree/bindings/net/amlogic,meson-dwmac.yaml b/Documentation/devicetree/bindings/net/amlogic,meson-dwmac.yaml
> index 6b057b117aa0..62a1e92a645c 100644
> --- a/Documentation/devicetree/bindings/net/amlogic,meson-dwmac.yaml
> +++ b/Documentation/devicetree/bindings/net/amlogic,meson-dwmac.yaml
> @@ -74,17 +74,68 @@ allOf:
>              Any configuration is ignored when the phy-mode is set to "rmii".
>  
>          amlogic,rx-delay-ns:
> +          deprecated: true
>            enum:
>              - 0
>              - 2
>            default: 0
> +          description:
> +            The internal RGMII RX clock delay in nanoseconds. Deprecated, use
> +            amlogic,rgmii-rx-delay-ps instead.
> +
> +        amlogic,rgmii-rx-delay-ps:
> +          default: 0
>            description:
>              The internal RGMII RX clock delay (provided by this IP block) in
> -            nanoseconds. When phy-mode is set to "rgmii" then the RX delay
> -            should be explicitly configured. When the phy-mode is set to
> -            either "rgmii-id" or "rgmii-rxid" the RX clock delay is already
> -            provided by the PHY. Any configuration is ignored when the
> -            phy-mode is set to "rmii".
> +            picoseconds. When phy-mode is set to "rgmii" or "rgmii-id" then
> +            the RX delay should be explicitly configured. When the phy-mode
> +            is set to either "rgmii-id" or "rgmii-rxid" the RX clock delay
> +            is already provided by the PHY so any configuration here is
> +            ignored. Also any configuration is ignored when the phy-mode is
> +            set to "rmii".
> +
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              - amlogic,meson8b-dwmac
> +              - amlogic,meson8m2-dwmac
> +              - amlogic,meson-gxbb-dwmac
> +              - amlogic,meson-axg-dwmac
> +    then:
> +      properties:
> +        amlogic,rgmii-rx-delay-ps:
> +          enum:
> +            - 0
> +            - 2000
> +
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              - amlogic,meson-g12a-dwmac
> +    then:
> +      properties:
> +        amlogic,rgmii-rx-delay-ps:
> +          enum:
> +            - 0
> +            - 200
> +            - 400
> +            - 600
> +            - 800
> +            - 1000
> +            - 1200
> +            - 1400
> +            - 1600
> +            - 1800
> +            - 2000
> +            - 2200
> +            - 2400
> +            - 2600
> +            - 2800
> +            - 3000
>  
>  properties:
>    compatible:
> -- 
> 2.29.2
>