Re: [PATCH 1/3] dt-bindings: pci: fsl,imx6q-pcie: Add extref clock for i.MX8MQ

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] The optional 'extref' clock was added to the Root Complex binding for i.MX8MQ but omitted from the corresponding Endpoint mode binding, resulting in schema validation failure if the endpoint uses the clock.
--

--- Patch [1]: [PATCH 1/3] dt-bindings: pci: fsl,imx6q-pcie: Add extref clock for i.MX8MQ ---
commit 4169458ec9055f45e1c7d18a9eea850e75cf9b6a
Author: Rudi Heitbaum <rudi@heitbaum.com>

dt-bindings: pci: fsl,imx6q-pcie: Add extref clock for i.MX8MQ

i.MX8MQ can drive PCIe REF_CLK either from the internal PLL or from an
off-chip oscillator. This allows an optional fifth extref clock to describe
the latter, matching the name already used for i.MX95.

> diff --git a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml
> index e8b8131f5f23b..8fb0c919ae572 100644
> --- a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml
> +++ b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml

[ ... ]

> @@ -173,13 +174,16 @@ allOf:
>      then:
>        properties:
>          clocks:
> -          maxItems: 4
> +          minItems: 4
> +          maxItems: 5
>          clock-names:
> +          minItems: 4
>            items:
>              - const: pcie
>              - const: pcie_bus
>              - const: pcie_phy
>              - const: pcie_aux
> +            - const: extref  # Optional

[Severity: Medium]
Will this same clock be used when the hardware is configured in endpoint mode?

Currently, this adds the optional extref clock to the root complex binding for
fsl,imx8mq-pcie, expanding the maximum items to 5. However, the corresponding
endpoint schema in fsl,imx6q-pcie-ep.yaml for fsl,imx8mq-pcie-ep still
restricts clocks to exactly 4 items:

Documentation/devicetree/bindings/pci/fsl,imx6q-pcie-ep.yaml:
  - if:
      properties:
        compatible:
          enum:
            - fsl,imx8mq-pcie-ep
            - fsl,imx95-pcie-ep
    then:
      properties:
        clocks:
          minItems: 4
          maxItems: 4

If an endpoint device tree describes the hardware using this 5th extref clock,
will it fail schema validation because the endpoint binding was not also
updated?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/cover.1785669457.git.rudi@heitbaum.com?part=1