Re: [PATCH 2/9] arm64: dts: marvell: Add AP806/CP110 syscon compatibles

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [Medium] arm64: dts: marvell: ap806-system-controller triggers legacy
  clk probe failure
--

commit d5587b2920b1facc3deb1cff76751746477ff106
Author: Rob Herring (Arm) <robh@kernel.org>

arm64: dts: marvell: Add AP806/CP110 syscon compatibles

This commit adds "marvell,ap806-system-controller" and
"marvell,cp110-system-controller" compatibles to the AP806 and CP110
system-controller syscon nodes.

> diff --git a/arch/arm64/boot/dts/marvell/armada-ap80x.dtsi b/arch/arm64/boot/dts/marvell/armada-ap80x.dtsi
> index 40e1469829212..0da13b2cd1fc0 100644
> --- a/arch/arm64/boot/dts/marvell/armada-ap80x.dtsi
> +++ b/arch/arm64/boot/dts/marvell/armada-ap80x.dtsi
> @@ -267,7 +267,8 @@ ap_sdhci0: mmc@6e0000 {
>  			};
>  
>  			ap_syscon0: system-controller@6f4000 {
> -				compatible = "syscon", "simple-mfd";
> +				compatible = "marvell,ap806-system-controller",
> +					     "syscon", "simple-mfd";
>  				reg = <0x6f4000 0x2000>;
>  
>  				ap_pinctrl: pinctrl {
> @@ -293,7 +294,8 @@ ap_gpio: gpio@1040 {
>  			};
>  
>  			ap_syscon1: system-controller@6f8000 {
> -				compatible = "syscon", "simple-mfd";
> +				compatible = "marvell,ap806-system-controller",
> +					     "syscon", "simple-mfd";
>  				reg = <0x6f8000 0x1000>;
>  				#address-cells = <1>;
>  				#size-cells = <1>;

[Severity: Medium]
Does adding "marvell,ap806-system-controller" to ap_syscon0 and ap_syscon1
cause both nodes to bind to ap806_syscon_legacy_driver and fail probe?

drivers/clk/mvebu/ap806-system-controller.c matches
"marvell,ap806-system-controller" for the deprecated flat-node clock
binding:

drivers/clk/mvebu/ap806-system-controller.c:ap806_syscon_legacy_probe() {
	dev_warn(&pdev->dev, FW_WARN "Using legacy device tree binding\n");
	dev_warn(&pdev->dev, FW_WARN "Update your device tree:\n");
	dev_warn(&pdev->dev, FW_WARN
		 "This binding won't be supported in future kernel\n");

	return ap806_syscon_common_probe(pdev, pdev->dev.of_node);
}

ap806_syscon_common_probe() then reads AP806_SAR_REG (offset 0x400) from
each syscon regmap (including System Controller 1 on ap_syscon1) and
checks pdev->dev.of_node against "marvell,ap806-clock" and
"marvell,ap807-clock".  Because pdev->dev.of_node is the parent
system-controller node rather than the clock child node, both devices emit
false FW_WARN messages, log "compatible not supported", and fail probe
with -EINVAL on every boot.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261111-dtbs-marvell-v1-0-938788aff3ae@kernel.org?part=2