Re: [PATCH 3/3] arm: dts: ti: omap: Prevent watchdog from being reset on kernel boot

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] The patch exposes the system to unexpected reboots due to a 30-second window before the watchdog is idled, contrary to the '3 second window' claimed in the commit message.
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commit 1abe23cd5472149baeeab9af481deaf65caccd1f
Author: Diogo Ivo <diogo.ivo@bootlin.com>
Subject: arm: dts: ti: omap: Prevent watchdog from being reset on kernel boot

This commit prevents the watchdog from being reset and idled during kernel
boot by adding the ti,no-reset-on-init property to the target-module node.
This is intended to provide a 3-second window for the watchdog driver to
probe without resetting the watchdog.

> diff --git a/arch/arm/boot/dts/ti/omap/omap4-l4.dtsi b/arch/arm/boot/dts/ti/omap/omap4-l4.dtsi
> index 4c78a0b28fab3..e061ea3fc8e70 100644
> --- a/arch/arm/boot/dts/ti/omap/omap4-l4.dtsi
> +++ b/arch/arm/boot/dts/ti/omap/omap4-l4.dtsi
> @@ -1126,6 +1126,7 @@ target-module@4000 {			/* 0x4a314000, ap 7 18.0 */
>  					<SYSC_IDLE_SMART>,
>  					<SYSC_IDLE_SMART_WKUP>;
>  			ti,syss-mask = <1>;
> +			ti,no-reset-on-init;

[Severity: High]
Does adding this property unintentionally cause a regression where the system
experiences unexpected reboots due to a 30-second delay instead of the
intended 3-second window?

Adding ti,no-reset-on-init skips the immediate hardware reset and triggers the
delayed work fallback in sysc_probe():

drivers/bus/ti-sysc.c:sysc_probe() {
    ...
    schedule_delayed_work(&ddata->idle_work, 3000);
    ...
}

Because schedule_delayed_work() takes its delay in jiffies rather than
milliseconds, passing 3000 evaluates to 3000 jiffies. On typical ARM
configurations where HZ=100 (the default), this results in a 30-second delay
instead of the expected 3 seconds.

This could lead to a boot loop if the bootloader configures a watchdog timeout
of less than 30 seconds and the system relies on the driver to stop it.

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Sashiko AI review · https://sashiko.dev/#/patchset/20260911-omap4-wdt_boot-v1-0-637d778a4a1e@bootlin.com?part=3