Re: [PATCH 30/34] arm64: dts: qcom: talos: Move PCIe phy and GPIOs to root port node

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] Moving `phys` and `reset-gpios` into the root port child node activates a pre-existing PHY initialization resource leak in `qcom_pcie_parse_port()` on probe deferral.
--

commit 97d4c74a5631a23e99d2209733340334556228ea
Author: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>

arm64: dts: qcom: talos: Move PCIe phy and GPIOs to root port node

This commit moves PCIe PHY and GPIO properties (perst/wake) from the RC
controller node to the root port node (pcie@0) in device tree files for
QCS615 and Talos.

> diff --git a/arch/arm64/boot/dts/qcom/qcs615-ride.dts b/arch/arm64/boot/dts/qcom/qcs615-ride.dts
> index 43f110ba3a7c5..4edd2b1bb03af 100644
> --- a/arch/arm64/boot/dts/qcom/qcs615-ride.dts
> +++ b/arch/arm64/boot/dts/qcom/qcs615-ride.dts
[ ... ]
> @@ -444,15 +444,17 @@ &mdss_dsi0_phy {
>  };
>  
>  &pcie {
> -	perst-gpios = <&tlmm 101 GPIO_ACTIVE_LOW>;
> -	wake-gpios = <&tlmm 100 GPIO_ACTIVE_LOW>;
> -
>  	pinctrl-0 = <&pcie_default_state>;
>  	pinctrl-names = "default";
>  
>  	status = "okay";
>  };
>  
> +&pcie_port0 {
> +	reset-gpios = <&tlmm 101 GPIO_ACTIVE_LOW>;

[Severity: High]
This isn't a bug introduced by this patch, but does moving reset-gpios into
the root port node activate a PHY resource leak during probe deferral?

In drivers/pci/controller/dwc/pcie-qcom.c, qcom_pcie_parse_port()
successfully gets the PHY and calls phy_init(), which increments the
init_count and enables clocks and regulators. Immediately afterward, it
calls qcom_pcie_parse_perst(), which requests reset-gpios.

If the GPIO controller probes later, this returns -EPROBE_DEFER:

drivers/pci/controller/dwc/pcie-qcom.c:qcom_pcie_parse_port() {
    ...
	ret = qcom_pcie_parse_perst(pcie, port, node);
	if (ret)
		return ret;
    ...
}

This error path returns without calling phy_exit() and without adding the
port to the pcie->ports list. As a result, the cleanup path in
qcom_pcie_parse_ports() also fails to invoke phy_exit().

This permanently leaks the phy_init() call on each probe deferral, meaning
the underlying clocks and regulators will never be disabled, even on system
suspend or driver unbind.

> +	wake-gpios = <&tlmm 100 GPIO_ACTIVE_LOW>;
> +};
> +
[ ... ]

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260910-root_port-v1-0-90a252ddbbfa@oss.qualcomm.com?part=30