Re: [PATCH 2/4] arm64: dts: qcom: x1e80100: Apply consistent critical thermal shutdown

From: Johan Hovold
Date: Wed Feb 19 2025 - 10:36:40 EST


On Wed, Feb 19, 2025 at 12:36:19PM +0100, Stephan Gerhold wrote:
> The firmware configures the TSENS controller with a maximum temperature of
> 120°C. When reaching that temperature, the hardware automatically triggers
> a reset of the entire platform. Some of the thermal zones in x1e80100.dtsi
> use a critical trip point of 125°C. It's impossible to reach those.
>
> It's preferable to shut down the system cleanly before reaching the
> hardware trip point. Make the critical temperature trip points consistent
> by setting all of them to 115°C and apply a consistent hysteresis.
> The ACPI tables also specify 115°C as critical shutdown temperature.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: 4e915987ff5b ("arm64: dts: qcom: x1e80100: Enable tsens and thermal zone nodes")
> Signed-off-by: Stephan Gerhold <stephan.gerhold@xxxxxxxxxx>

> @@ -8483,7 +8483,7 @@ trip-point1 {
> };
>
> cpu-critical {
> - temperature = <110000>;
> + temperature = <115000>;

Have you asked the authors where this lower limit came from (or
determined it was just copy pasta some other way)?

> hysteresis = <1000>;
> type = "critical";
> };

> @@ -8737,7 +8737,7 @@ trip-point0 {
> };
>
> video-critical {
> - temperature = <125000>;
> + temperature = <115000>;
> hysteresis = <1000>;
> type = "critical";
> };

Ok, make sense to backport the first patch as well then.

Looks good to me:

Reviewed-by: Johan Hovold <johan+linaro@xxxxxxxxxx>