Re: [PATCH v2 12/12] arm64: dts: qcom: sc8280xp-x13s: Add thermal zone support

[Konrad Dybcio]

On 29.10.2022 07:14, Manivannan Sadhasivam wrote:
> Add thermal zone support by making use of the thermistor SYS_THERM6.
> Based on experiments, this thermistor seems to reflect the actual
> surface temperature of the laptop.
> 
> For the cooling device, all BIG CPU cores are throttle down to keep the
s/throttle/throttled

Is it okay to let the 4xA78C run at full throttle in thermal emergencies though?
> temperature at a sane level.
> 
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> ---
>  .../qcom/sc8280xp-lenovo-thinkpad-x13s.dts    | 46 +++++++++++++++++++
>  1 file changed, 46 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sc8280xp-lenovo-thinkpad-x13s.dts b/arch/arm64/boot/dts/qcom/sc8280xp-lenovo-thinkpad-x13s.dts
> index ca77c19c6d0d..96e2fa72f782 100644
> --- a/arch/arm64/boot/dts/qcom/sc8280xp-lenovo-thinkpad-x13s.dts
> +++ b/arch/arm64/boot/dts/qcom/sc8280xp-lenovo-thinkpad-x13s.dts
> @@ -29,6 +29,52 @@ backlight {
>  		pinctrl-0 = <&edp_bl_en>, <&edp_bl_pwm>;
>  	};
>  
> +	thermal-zones {
> +		skin-temp-thermal {
> +			polling-delay-passive = <250>;
> +			polling-delay = <0>;
> +			thermal-sensors = <&pmk8280_adc_tm 5>;
> +
> +			trips {
> +				skin_temp_alert0: trip-point0 {
> +					temperature = <55000>;
> +					hysteresis = <1000>;
> +					type = "passive";
> +				};
> +
> +				skin_temp_alert1: trip-point1 {
> +					temperature = <58000>;
> +					hysteresis = <1000>;
> +					type = "passive";
> +				};
> +
> +				skin-temp-crit {
> +					temperature = <73000>;
Ouch, I didn't know we were serving burnt fingers at the cafeteria today :D

Or maybe this just looks scary.. The laptop looks plastic, so maybe it won't cause instant
burns?

Konrad
> +					hysteresis = <1000>;
> +					type = "critical";
> +				};
> +			};
> +
> +			cooling-maps {
> +				map0 {
> +					trip = <&skin_temp_alert0>;
> +					cooling-device = <&CPU4 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&CPU5 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&CPU6 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&CPU7 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> +				};
> +
> +				map1 {
> +					trip = <&skin_temp_alert1>;
> +					cooling-device = <&CPU4 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&CPU5 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&CPU6 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&CPU7 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> +				};
> +			};
> +		};
> +	};
> +
>  	vreg_edp_bl: regulator-edp-bl {
>  		compatible = "regulator-fixed";
>