Re: [PATCH 1/5] arm64: dts: qcom: qcs6490-rb3gen2: use pci for device nodes

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Conceptual Flaw / False Premise: Renaming the node does not prevent it from being treated as a PCI bus because `device_type = "pci"` is still present.
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commit 3cd795cb2f33ffae376d5bceb9ba0da490602d05
Author: Alex Elder <elder@riscstar.com>

arm64: dts: qcom: qcs6490-rb3gen2: use pci for device nodes

This commit renames devicetree nodes from pcie@ to pci@ with the intent of
stopping the embedded PCIe endpoints from being treated as PCI buses by the
devicetree parsing code.

> diff --git a/arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts b/arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts
> index a13315bf0fb07..99a985a177a61 100644
> --- a/arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts
> +++ b/arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts
> @@ -954,7 +954,7 @@ pcie@3,0 {
>  			ranges;
>  			bus-range = <0x5 0xff>;
>  
> -			pcie@0,0 {
> +			pci@0,0 {
>  				reg = <0x50000 0x0 0x0 0x0 0x0>;
>  				#address-cells = <3>;
>  				#size-cells = <2>;
>  				device_type = "pci";

[Severity: Medium]
Does this node rename actually prevent the devicetree parsing code from
treating it as a PCI bus?

The commit message indicates that renaming the node away from pcie@ will stop
of_node_is_pcie() from matching it. However, because this node explicitly
specifies device_type = "pci", of_bus_pci_match() in drivers/of/address.c
will still return true immediately.

When evaluating buses, of_bus_pci_match() checks:

    of_node_is_type(np, "pci") || of_node_is_pcie(np)

Since the device type is explicitly "pci", the match succeeds before
of_node_is_pcie() is evaluated. Should device_type = "pci" also be removed to
actually prevent this endpoint from being treated as a PCI bridge?

[ ... ]

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Sashiko AI review · https://sashiko.dev/#/patchset/20260901172058.1512508-1-elder@riscstar.com?part=1