Re: [PATCH 1/6] clocksource/drivers/timer-tegra: Keep Tegra20's watchdog timers free

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [Low] clocksource/drivers/timer-tegra: missing Fixes trailer for
  f6d50ec5f85c
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commit 65df25a211b643454125037a766cc25969d41802
Author: Artur Kowalski <arturkow2000@gmail.com>

> clocksource/drivers/timer-tegra: Keep Tegra20's watchdog timers free
>
> Tegra20 has no watchdog block. Instead, the clock and reset controller
> resets the system when the interrupt of TIMER1 or TIMER2 fires while
> the previous one is still pending. A bootloader can start this watchdog
> and leave it running for the kernel.
>
> Since commit f6d50ec5f85c ("clocksource/drivers/tegra: Support per-CPU
> timers on all Tegra's"), the driver uses TIMER1-2 as the per-CPU clock
> event devices on Tegra20, where it used TIMER3 before. When CPU0's
> clock event device takes over TIMER1, the clock and reset controller
> still resets the system if a timer interrupt fires while the previous
> one hasn't been handled yet, which resets about half of the boots
> early. If the system survives that, the watchdog stays enabled but
> never fires, as CPU0 keeps clearing the timer's interrupts.
>
> Use TIMER3-4 for the per-CPU clock event devices on Tegra20, leaving
> TIMER1-2 to the watchdog. Tegra30 needs TIMER1-4 for its four CPUs and
> its watchdog uses TIMER5, so keep its mapping.
>
> A watchdog left running by the bootloader is then no longer disarmed,
> so it resets the system unless it is pinged. That needs the tegra_wdt
> driver, which gains Tegra20 support in the following patches, built in
> or loaded before the watchdog's timeout expires.
>
> Assisted-by: Claude:claude-opus-5-5
> Signed-off-by: Artur Kowalski <arturkow2000@gmail.com>

[Severity: Low]
This fixes a boot regression introduced by the commit cited in the
changelog.  Should this include:

  Fixes: f6d50ec5f85c ("clocksource/drivers/tegra: Support per-CPU timers on all Tegra's")

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Sashiko AI review · https://sashiko.dev/#/patchset/20261110-t20-for-upstream-v1-0-5923449951fe@gmail.com?part=1