Re: [PATCH V4 1/7] arm: dts: imx6qdl-sabresd: Move power supply property to Root Port node

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [High] Removing the legacy `vpcie-supply` property breaks PCIe initialization on older kernels and non-pwrctrl environments.
- [Medium] Adding `vpcie3v3-supply` to the Root Port node without documenting it in the binding schema causes a schema validation failure.
--

commit 1190644448a0f1a3780ae7b3d2a75e1606ab6017
Author: Sherry Sun <sherry.sun@nxp.com>
arm: dts: imx6qdl-sabresd: Move power supply property to Root Port node

This commit moves the power supply property from the PCIe controller node
to the Root Port child node. This change aims to support the new PCI pwrctrl
framework.

> diff --git a/arch/arm/boot/dts/nxp/imx/imx6qdl-sabresd.dtsi b/arch/arm/boot/dts/nxp/imx/imx6qdl-sabresd.dtsi
> index fe9046c03ddd6..c52b8897f9995 100644
> --- a/arch/arm/boot/dts/nxp/imx/imx6qdl-sabresd.dtsi
> +++ b/arch/arm/boot/dts/nxp/imx/imx6qdl-sabresd.dtsi
> @@ -756,12 +756,12 @@ &pcie {
>  	pinctrl-0 = <&pinctrl_pcie>;
>  	/* This property is deprecated, use reset-gpios from the Root Port node. */
>  	reset-gpio = <&gpio7 12 GPIO_ACTIVE_LOW>;
> -	vpcie-supply = <&reg_pcie>;

[Severity: High]
Will removing the legacy vpcie-supply property break backward compatibility
with older drivers?

Older drivers, such as pci-imx6.c, looking for this property via
devm_regulator_get_optional("vpcie") in the host bridge node will receive
an error code and silently skip enabling the PCIe regulator. Because the
regulator lacks an always-on constraint, it will remain off, which can cause
PCIe link failures on older kernels or when booting with the generic PCI power
control framework disabled.

Device trees generally act as stable hardware descriptions. Can this property
be kept in the parent node while adding vpcie3v3-supply to the child node,
since the regulator core can safely handle multiple consumers?

>  	status = "okay";
>  };
>  
>  &pcie_port0 {
>  	reset-gpios = <&gpio7 12 GPIO_ACTIVE_LOW>;
> +	vpcie3v3-supply = <&reg_pcie>;

[Severity: Medium]
Could adding vpcie3v3-supply here without documenting it in the binding
schema cause a schema validation failure?

The pcie@0 node definition in the fsl,imx6q-pcie.yaml binding schema
uses "unevaluatedProperties: false", meaning all properties must be explicitly
documented. Since vpcie3v3-supply is not documented in that file or in the
core PCI schemas, the schema validator will likely reject it.

>  };

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260630060710.3294811-1-sherry.sun@oss.nxp.com?part=1