Re: [PATCH 1/2] dt-bindings: phy: ti: phy-gmii-sel: Add bindings for J7200

[Roger Quadros <rogerq@kernel.org>]

Hi Siddharth,

On 31/05/2022 14:12, Siddharth Vadapalli wrote:
> TI's J7200 SoC supports additional PHY modes like QSGMII and SGMII
> that are not supported on earlier SoCs. Add a compatible for it.
> 
> Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com>
> ---
>  .../mfd/ti,j721e-system-controller.yaml       |  5 ++++
>  .../bindings/phy/ti,phy-gmii-sel.yaml         | 24 ++++++++++++++++++-
>  2 files changed, 28 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/mfd/ti,j721e-system-controller.yaml b/Documentation/devicetree/bindings/mfd/ti,j721e-system-controller.yaml
> index fa86691ebf16..e381ba62a513 100644
> --- a/Documentation/devicetree/bindings/mfd/ti,j721e-system-controller.yaml
> +++ b/Documentation/devicetree/bindings/mfd/ti,j721e-system-controller.yaml
> @@ -48,6 +48,11 @@ patternProperties:
>      description:
>        This is the SERDES lane control mux.
>  
> +  "phy@[0-9a-f]+$":
> +    type: object
> +    description:
> +      This is the register to set phy mode through phy-gmii-sel driver.
> +

Is this really required? The system controller has 100s of different such registers and it is not practical to mention about all.

>  required:
>    - compatible
>    - reg
> diff --git a/Documentation/devicetree/bindings/phy/ti,phy-gmii-sel.yaml b/Documentation/devicetree/bindings/phy/ti,phy-gmii-sel.yaml
> index ff8a6d9eb153..7427758451e7 100644
> --- a/Documentation/devicetree/bindings/phy/ti,phy-gmii-sel.yaml
> +++ b/Documentation/devicetree/bindings/phy/ti,phy-gmii-sel.yaml
> @@ -53,12 +53,21 @@ properties:
>        - ti,am43xx-phy-gmii-sel
>        - ti,dm814-phy-gmii-sel
>        - ti,am654-phy-gmii-sel
> +      - ti,j7200-cpsw5g-phy-gmii-sel

Why not just "ti,j7200-phy-gmii-sel" so it is consistent naming.

>  
>    reg:
>      maxItems: 1
>  
>    '#phy-cells': true
>  
> +  ti,enet-ctrl-qsgmii:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: |
> +      Required only for QSGMII mode. Bitmask to select the port for
> +      QSGMII main mode. Rest of the ports are selected as QSGMII_SUB
> +      ports automatically. Any of the 4 CPSW5G ports can act as the
> +      main port with the rest of them being the QSGMII_SUB ports.
> +

This is weird way of doing things.

The Ethernet controller driver already knows which mode the port is
supposed to operate.

e.g.
+&cpsw0_port1 {
+	phy-handle = <&cpsw5g_phy0>;
+	phy-mode = "qsgmii";
+	mac-address = [00 00 00 00 00 00];
+	phys = <&cpsw0_phy_gmii_sel 1>;
+};
+
+&cpsw0_port2 {
+	phy-handle = <&cpsw5g_phy1>;
+	phy-mode = "qsgmii-sub";
+	mac-address = [00 00 00 00 00 00];
+	phys = <&cpsw0_phy_gmii_sel 2>;

And it can convey the mode to the PHY driver via phy_ops->set_mode.
So you should be depending on that instead of adding this new property.

>  allOf:
>    - if:
>        properties:
> @@ -73,6 +82,19 @@ allOf:
>          '#phy-cells':
>            const: 1
>            description: CPSW port number (starting from 1)
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              - ti,j7200-cpsw5g-phy-gmii-sel
> +    then:
> +      properties:
> +        '#phy-cells':
> +          const: 1
> +          description: CPSW port number (starting from 1)
> +        ti,enet-ctrl-qsgmii:
> +          enum: [1, 2, 4, 8]
>    - if:
>        properties:
>          compatible:
> @@ -97,7 +119,7 @@ additionalProperties: false
>  
>  examples:
>    - |
> -    phy_gmii_sel: phy-gmii-sel@650 {
> +    phy_gmii_sel: phy@650 {
>          compatible = "ti,am3352-phy-gmii-sel";
>          reg = <0x650 0x4>;
>          #phy-cells = <2>;

cheers,
-roger