Re: [PATCH 1/9] dt-bindings: phy: cadence-sierra: Add bindings for the PLLs within SERDES

[Rob Herring <robh@kernel.org>]

On Tue, Nov 03, 2020 at 09:25:48AM +0530, Kishon Vijay Abraham I wrote:
> Add binding for the PLLs within SERDES.
> 
> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
> ---
>  .../bindings/phy/phy-cadence-sierra.yaml      | 89 ++++++++++++++++++-
>  1 file changed, 86 insertions(+), 3 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/phy/phy-cadence-sierra.yaml b/Documentation/devicetree/bindings/phy/phy-cadence-sierra.yaml
> index d210843863df..f574b8ed358c 100644
> --- a/Documentation/devicetree/bindings/phy/phy-cadence-sierra.yaml
> +++ b/Documentation/devicetree/bindings/phy/phy-cadence-sierra.yaml
> @@ -49,12 +49,14 @@ properties:
>      const: serdes
>  
>    clocks:
> -    maxItems: 2
> +    maxItems: 4
>  
>    clock-names:
>      items:
>        - const: cmn_refclk_dig_div
>        - const: cmn_refclk1_dig_div
> +      - const: pll_cmnlc
> +      - const: pll_cmnlc1
>  
>    cdns,autoconf:
>      type: boolean
> @@ -107,6 +109,58 @@ patternProperties:
>  
>      additionalProperties: false
>  
> +  "^refrcv1?$":
> +    type: object
> +    description: |
> +      Reference receivers that enables routing external clocks to the alternate
> +      PLLCMNLC.
> +    properties:
> +      clocks:
> +        maxItems: 1
> +        description: Phandle to clock nodes representing the input to the
> +          reference receiver.
> +
> +      clock-names:
> +        items:
> +          - const: pll_refclk
> +
> +      "#clock-cells":
> +        const: 0
> +
> +    required:
> +      - clocks
> +      - "#clock-cells"
> +
> +  "^pll_cmnlc1?$":
> +    type: object
> +    description: |
> +      SERDES node should have subnodes for each of the PLLs present in
> +      the SERDES.
> +    properties:
> +      clocks:
> +        maxItems: 2
> +        description: Phandle to clock nodes representing the two inputs to PLL.
> +
> +      clock-names:
> +        items:
> +          - const: pll_refclk
> +          - const: refrcv
> +
> +      "#clock-cells":
> +        const: 0
> +
> +      assigned-clocks:
> +        maxItems: 1
> +
> +      assigned-clock-parents:
> +        maxItems: 1
> +
> +    required:
> +      - clocks
> +      - "#clock-cells"
> +      - assigned-clocks
> +      - assigned-clock-parents
> +
>  required:
>    - compatible
>    - "#address-cells"
> @@ -130,10 +184,39 @@ examples:
>              reg = <0x0 0xfd240000 0x0 0x40000>;
>              resets = <&phyrst 0>, <&phyrst 1>;
>              reset-names = "sierra_reset", "sierra_apb";
> -            clocks = <&cmn_refclk_dig_div>, <&cmn_refclk1_dig_div>;
> -            clock-names = "cmn_refclk_dig_div", "cmn_refclk1_dig_div";
> +            clocks = <&cmn_refclk_dig_div>, <&cmn_refclk1_dig_div>, <&serdes_pll_cmnlc>, <&serdes_pll_cmnlc1>;
> +            clock-names = "cmn_refclk_dig_div", "cmn_refclk1_dig_div", "pll_cmnlc", "pll_cmnlc1";
>              #address-cells = <1>;
>              #size-cells = <0>;
> +
> +            serdes_refrcv: refrcv {
> +                    clocks = <&pll0_refclk>;
> +                    clock-names = "pll_refclk";
> +                    #clock-cells = <0>;
> +            };
> +
> +            serdes_refrcv1: refrcv1 {
> +                    clocks = <&pll1_refclk>;
> +                    clock-names = "pll_refclk";
> +                    #clock-cells = <0>;
> +            };
> +
> +            serdes_pll_cmnlc: pll_cmnlc {
> +                    clocks = <&pll0_refclk>, <&serdes_refrcv1>;
> +                    clock-names = "pll_refclk", "refrcv";
> +                    #clock-cells = <0>;
> +                    assigned-clocks = <&serdes_pll_cmnlc>;

Isn't assigned-clocks supposed to be one of the clocks in 'clocks'?

> +                    assigned-clock-parents = <&pll0_refclk>;

And this should not be a clock in 'clocks'...


More generally, why do we need to expose all these details in DT?

Rob