Re: [PATCH v3 1/2] dt-binding: pci-imx6: Add external reference clock mode support

[Krzysztof Kozlowski <krzk@kernel.org>]

On Fri, Jun 20, 2025 at 11:13:49AM GMT, Richard Zhu wrote:
> On i.MX, the PCIe reference clock might come from either internal
> system PLL or external clock source.
> Add the external reference clock source for reference clock.
> 
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> Reviewed-by: Frank Li <Frank.Li@nxp.com>
> ---
>  Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml
> index ca5f2970f217..c472a5daae6e 100644
> --- a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml
> +++ b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml
> @@ -219,7 +219,12 @@ allOf:
>              - const: pcie_bus
>              - const: pcie_phy
>              - const: pcie_aux
> -            - const: ref
> +            - description: PCIe reference clock.
> +              oneOf:
> +                - description: The controller might be configured clocking
> +                    coming in from either an internal system PLL or an
> +                    external clock source.
> +                  enum: [ref, gio]

Internal like within PCIe or coming from other SoC block? What does
"gio" mean?

Best regards,
Krzysztof