Re: [PATCH 6/7] ARM: dts: arm/vexpress: Fix Cortex-A15 GIC compatibles

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] ARM: dts: vexpress: dropping arm,cortex-a9-gic breaks GIC init on v2p-ca5s
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commit 35f1a8a2621e891a6464121f2faf6970b2efbbab
Author: Rob Herring (Arm) <robh@kernel.org>

ARM: dts: arm/vexpress: Fix Cortex-A15 GIC compatibles

This commit drops the "arm,cortex-a9-gic" fallback compatible from the GIC
interrupt-controller nodes in three Versatile Express device trees.

> diff --git a/arch/arm/boot/dts/arm/vexpress-v2p-ca5s.dts b/arch/arm/boot/dts/arm/vexpress-v2p-ca5s.dts
> index c716e60a8be0b..a5e0dde254ab3 100644
> --- a/arch/arm/boot/dts/arm/vexpress-v2p-ca5s.dts
> +++ b/arch/arm/boot/dts/arm/vexpress-v2p-ca5s.dts
> @@ -119,7 +119,7 @@ watchdog@2c000620 {
>  	};
>  
>  	gic: interrupt-controller@2c001000 {
> -		compatible = "arm,cortex-a5-gic", "arm,cortex-a9-gic";
> +		compatible = "arm,cortex-a5-gic";

[Severity: High]
Does dropping "arm,cortex-a9-gic" from gic: interrupt-controller@2c001000 in
arch/arm/boot/dts/arm/vexpress-v2p-ca5s.dts break GIC initialization when
booting V2P-CA5s?

In arch/arm/mach-versatile/v2m.c, DT_MACHINE_START(VEXPRESS_DT) relies on
init_IRQ() -> irqchip_init() -> of_irq_init(__irqchip_of_table) to match the
root interrupt controller. However, drivers/irqchip/irq-gic.c does not declare
a match for "arm,cortex-a5-gic":

drivers/irqchip/irq-gic.c:
    IRQCHIP_DECLARE(gic_400, "arm,gic-400", gic_of_init);
    IRQCHIP_DECLARE(arm11mp_gic, "arm,arm11mp-gic", gic_of_init);
    IRQCHIP_DECLARE(arm1176jzf_dc_gic, "arm,arm1176jzf-devchip-gic", gic_of_init);
    IRQCHIP_DECLARE(cortex_a15_gic, "arm,cortex-a15-gic", gic_of_init);
    IRQCHIP_DECLARE(cortex_a9_gic, "arm,cortex-a9-gic", gic_of_init);
    IRQCHIP_DECLARE(cortex_a7_gic, "arm,cortex-a7-gic", gic_of_init);
    IRQCHIP_DECLARE(msm_8660_qgic, "qcom,msm-8660-qgic", gic_of_init);
    IRQCHIP_DECLARE(msm_qgic2, "qcom,msm-qgic2", gic_of_init);
    IRQCHIP_DECLARE(pl390, "arm,pl390", gic_of_init);

Without the "arm,cortex-a9-gic" fallback or an IRQCHIP_DECLARE entry for
"arm,cortex-a5-gic" in drivers/irqchip/irq-gic.c, of_irq_init() will not find
a matching driver for the primary interrupt controller on V2P-CA5s.

Also, the commit subject and message only mention Cortex-A15 and
"arm,cortex-a15-gic". Was the change to vexpress-v2p-ca5s.dts unintended?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261105-dt-vexpress-dts-fixes-v1-0-66615c3c8ec3@kernel.org?part=6