Re: [PATCH net-next v7 1/6] dt-bindings: net: Add tx and rx internal delays

From: Andrew Lunn
Date: Wed Jun 17 2020 - 22:01:19 EST


On Wed, Jun 17, 2020 at 01:20:14PM -0500, Dan Murphy wrote:
> tx-internal-delays and rx-internal-delays are a common setting for RGMII
> capable devices.
>
> These properties are used when the phy-mode or phy-controller is set to
> rgmii-id, rgmii-rxid or rgmii-txid. These modes indicate to the
> controller that the PHY will add the internal delay for the connection.
>
> Signed-off-by: Dan Murphy <dmurphy@xxxxxx>
> ---
> .../devicetree/bindings/net/ethernet-phy.yaml | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> index 9b1f1147ca36..b2887476fe6a 100644
> --- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> +++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> @@ -162,6 +162,17 @@ properties:
> description:
> Specifies a reference to a node representing a SFP cage.
>
> +
> + rx-internal-delay-ps:
> + description: |
> + RGMII Receive PHY Clock Delay defined in pico seconds. This is used for
> + PHY's that have configurable RX internal delays.
> +
> + tx-internal-delay-ps:
> + description: |
> + RGMII Transmit PHY Clock Delay defined in pico seconds. This is used for
> + PHY's that have configurable TX internal delays.
> +

So in a later patch you have:

default: 2000

That seems to apply that these values only apply when the phy mode
indicates a delay is needed. It would be good to document that here,
when each of these properties will be used. Also, that they default to
2000 when not present.

Andrew