Re: [PATCH 23/24] ARM: dts: zte: Add ZX279128S SoC description

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] dts: incorrect interrupt configuration for Cortex-A9 TWD watchdog
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commit bc197aaf9d71e07d72ae7dee27293f05bc2999cc
Author: Navid Ghahremani <ghahramani.navid@gmail.com>

ARM: dts: zte: Add ZX279128S SoC description

This patch adds the initial Device Tree representation for the ZTE
ZX279128S SoC. It defines the dual Cortex-A9 CPUs, along with clocks,
timers, GIC, L2 cache, and various peripheral controllers.

> diff --git a/arch/arm/boot/dts/zte/zx279128s.dtsi b/arch/arm/boot/dts/zte/zx279128s.dtsi
> new file mode 100644
> index 0000000000000..e2bbc70de319f
> --- /dev/null
> +++ b/arch/arm/boot/dts/zte/zx279128s.dtsi
> @@ -0,0 +1,397 @@
> +// SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause

[ ... ]

> +		timer@800600 {
> +			compatible = "arm,cortex-a9-twd-timer";
> +			reg = <0x00800600 0x20>;
> +			interrupts = <GIC_PPI 13 (GIC_CPU_MASK_SIMPLE(2) | IRQ_TYPE_EDGE_RISING)>;
> +			clocks = <&topcrm ZX279128S_TOP_A9_PERIPH>;
> +		};
> +
> +		watchdog@800620 {
> +			compatible = "arm,cortex-a9-twd-wdt";
> +			reg = <0x00800620 0x20>;
> +			interrupts = <GIC_PPI 14 (GIC_CPU_MASK_SIMPLE(1) | IRQ_TYPE_LEVEL_HIGH)>;

[Severity: Medium]
Will this interrupt configuration drop interrupts for CPU 1 and break
symmetric SMP lockup detection?

Since the system has dual cores (cpu@0 and cpu@1), it seems like this
should use GIC_CPU_MASK_SIMPLE(2), similar to the timer@800600 node above.

Also, is IRQ_TYPE_LEVEL_HIGH the correct trigger type? The Cortex-A9 TWD
watchdog interrupts are inherently edge-triggered. Configuring an
edge-triggered private peripheral interrupt as level-triggered can cause
missed or spurious interrupts in the GIC state tracking.

> +			clocks = <&topcrm ZX279128S_TOP_A9_PERIPH>;
> +			status = "disabled";
> +		};

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Sashiko AI review · https://sashiko.dev/#/patchset/20261010130024.177503-1-ghahramani.navid@gmail.com?part=23