[PATCH 0/3] arm64: dts: qcom: hamoa-crd: Introduce thermistor-based CPU throttling

[PATCH 0/3] arm64: dts: qcom: hamoa-crd: Introduce thermistor-based CPU throttling

[Bjorn Andersson]

The Hamoa CRD has multiple thermistors throughout the board to allow
measuring the temperature across different parts of the system. In line
with other platforms these are wired to the PMIC ADC and thermal monitor
blocks.

While "limits" hardware management provides rapid throttling of the
CPU cores, software needs to throttle the system e.g. during prolonged
CPU usage. Wire up the 7 thermistors found in the CRD as thermal zones
and throttle the CPU based on the "keyboard hotspot" thermistor.

The same mechanism is used on other Hamoa-based boards, but the
thermistor configuration and mapping is board-specific. As such, these
settings goes into the CRD dts. It's plausible that it could be shared
with the Purwa CRD, but this hasn't been confirmed.

Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
---
Bjorn Andersson (3):
      arm64: dts: qcom: hamoa-pmics: Mark pmk8550_vadc thermal sensor provider
      arm64: dts: qcom: hamoa-crd: Add thermal control
      arm64: defconfig: Enable PMIC5 Gen3 ADC thermal monitor

 arch/arm64/boot/dts/qcom/hamoa-pmics.dtsi |   1 +
 arch/arm64/boot/dts/qcom/x1e80100-crd.dts | 116 ++++++++++++++++++++++++++++++
 arch/arm64/configs/defconfig              |   2 +
 3 files changed, 119 insertions(+)
---
base-commit: 3d83758432b5e6ed9507500a57efb0f3af41ee7d
change-id: 20260830-hamoa-sys-therm-fb4f80fd6770

Best regards,
--  
Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>

[PATCH 1/3] arm64: dts: qcom: hamoa-pmics: Mark pmk8550_vadc thermal sensor provider

[Bjorn Andersson]

The PMK8550 VADC is typically providing thermal measurements based on
on-board thermistors, define #thermal-sensor-cells to allow referencing
it as such.

Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/hamoa-pmics.dtsi | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/boot/dts/qcom/hamoa-pmics.dtsi b/arch/arm64/boot/dts/qcom/hamoa-pmics.dtsi
index 17d754d57e18..7fad4a9b92fa 100644
--- a/arch/arm64/boot/dts/qcom/hamoa-pmics.dtsi
+++ b/arch/arm64/boot/dts/qcom/hamoa-pmics.dtsi
@@ -288,6 +288,7 @@ pmk8550_vadc: adc@9000 {
 			#address-cells = <1>;
 			#size-cells = <0>;
 			#io-channel-cells = <1>;
+			#thermal-sensor-cells = <1>;
 			pinctrl-0 = <&sys_therm_0_gpio3>, <&sys_therm_1_gpio4>;
 			pinctrl-names = "default";
 

-- 
2.55.0

[PATCH 2/3] arm64: dts: qcom: hamoa-crd: Add thermal control

[Bjorn Andersson]

The "limits" hardware performs rapid thermal management of the CPU
cores, but during prolonged CPU usage the system's overall temperature
need to be further managed by software.

The reference design provides seven "system thermistors", connected to
the PMK8550 VADC. Particularly interesting is the "keyboard hotspot
thermistor", which is wired up to sys_therm1.

Use this to throttle the CPUs, in the same way that we're throttling
previous generation laptops based on "skin-temp". The trips are chosen
from those existing examples, but are comparable with the ACPI thermal
policy.

While not used for cooling/throttling, also add the other thermal zones
for temperature reporting purposes.

Enable thermal-monitor mode for all 7 channels in the ADC.

Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/x1e80100-crd.dts | 116 ++++++++++++++++++++++++++++++
 1 file changed, 116 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/x1e80100-crd.dts b/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
index 429deffcf3e9..065af18357d7 100644
--- a/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
+++ b/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
@@ -11,6 +11,92 @@
 / {
 	model = "Qualcomm Technologies, Inc. X1E80100 CRD";
 	compatible = "qcom,x1e80100-crd", "qcom,x1e80100";
+
+	thermal-zones {
+		soc-thermal {
+			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX1_GPIO_100K_PU(1)>;
+		};
+
+		keyboard-thermal {
+			polling-delay-passive = <250>;
+
+			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX2_GPIO_100K_PU(1)>;
+
+			trips {
+				skin_alert0: trip-point0 {
+					temperature = <55000>;
+					hysteresis = <1000>;
+					type = "passive";
+				};
+
+				skin_alert1: trip-point1 {
+					temperature = <58000>;
+					hysteresis = <1000>;
+					type = "passive";
+				};
+
+				skin-crit {
+					temperature = <73000>;
+					hysteresis = <1000>;
+					type = "critical";
+				};
+			};
+
+			cooling-maps {
+				map0 {
+					trip = <&skin_alert0>;
+					cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu2 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu3 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&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>,
+							 <&cpu8 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu9 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu10 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu11 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+				};
+
+				map1 {
+					trip = <&skin_alert1>;
+					cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu2 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu3 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&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>,
+							 <&cpu8 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu9 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu10 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu11 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+				};
+			};
+		};
+
+		backcover-thermal {
+			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX1_THM_100K_PU(1)>;
+		};
+
+		smb-thermal {
+			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX2_THM_100K_PU(1)>;
+		};
+
+		sdx-thermal {
+			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX3_THM_100K_PU(1)>;
+		};
+
+		east-thermal {
+			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX4_THM_100K_PU(1)>;
+		};
+
+		west-thermal {
+			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX5_THM_100K_PU(1)>;
+		};
+	};
 };
 
 &gpu_zap_shader {
@@ -20,3 +106,33 @@ &gpu_zap_shader {
 &iris {
 	status = "okay";
 };
+
+&pmk8550_vadc {
+	channel@144 {
+		qcom,adc-tm;
+	};
+
+	channel@145 {
+		qcom,adc-tm;
+	};
+
+	channel@146 {
+		qcom,adc-tm;
+	};
+
+	channel@147 {
+		qcom,adc-tm;
+	};
+
+	channel@148 {
+		qcom,adc-tm;
+	};
+
+	channel@14a {
+		qcom,adc-tm;
+	};
+
+	channel@14b {
+		qcom,adc-tm;
+	};
+};

-- 
2.55.0

[PATCH 3/3] arm64: defconfig: Enable PMIC5 Gen3 ADC thermal monitor

[Bjorn Andersson]

All Hamoa-based devices uses PMIC5 Gen3 ADC connected to thermistors for
measuring temperature across the system.

Enable the Gen3 ADC, and it's associated ADC_TM auxiliary, drivers to
enable these use cases.

Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
---
 arch/arm64/configs/defconfig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
index 6ec8d3a69c98..08ff68643e21 100644
--- a/arch/arm64/configs/defconfig
+++ b/arch/arm64/configs/defconfig
@@ -800,6 +800,7 @@ CONFIG_TEGRA_BPMP_THERMAL=m
 CONFIG_GENERIC_ADC_THERMAL=m
 CONFIG_QCOM_TSENS=y
 CONFIG_QCOM_SPMI_ADC_TM5=m
+CONFIG_QCOM_SPMI_ADC_TM5_GEN3=m
 CONFIG_QCOM_SPMI_TEMP_ALARM=m
 CONFIG_QCOM_LMH=m
 CONFIG_UNIPHIER_THERMAL=y
@@ -1699,6 +1700,7 @@ CONFIG_MEDIATEK_MT6359_AUXADC=m
 CONFIG_MEDIATEK_MT6577_AUXADC=m
 CONFIG_QCOM_SPMI_VADC=m
 CONFIG_QCOM_SPMI_ADC5=m
+CONFIG_QCOM_SPMI_ADC5_GEN3=m
 CONFIG_ROCKCHIP_SARADC=m
 CONFIG_RZG2L_ADC=m
 CONFIG_RZT2H_ADC=m

-- 
2.55.0

Re: [PATCH 3/3] arm64: defconfig: Enable PMIC5 Gen3 ADC thermal monitor

[Abel Vesa]

On 26-08-30 21:02:04, Bjorn Andersson wrote:
> All Hamoa-based devices uses PMIC5 Gen3 ADC connected to thermistors for
> measuring temperature across the system.
> 
> Enable the Gen3 ADC, and it's associated ADC_TM auxiliary, drivers to
> enable these use cases.
> 
> Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>

Reviewed-by: Abel Vesa <abel.vesa@oss.qualcomm.com>

Re: [PATCH 2/3] arm64: dts: qcom: hamoa-crd: Add thermal control

[Abel Vesa]

On 26-08-30 21:02:03, Bjorn Andersson wrote:
> The "limits" hardware performs rapid thermal management of the CPU
> cores, but during prolonged CPU usage the system's overall temperature
> need to be further managed by software.
> 
> The reference design provides seven "system thermistors", connected to
> the PMK8550 VADC. Particularly interesting is the "keyboard hotspot
> thermistor", which is wired up to sys_therm1.
> 
> Use this to throttle the CPUs, in the same way that we're throttling
> previous generation laptops based on "skin-temp". The trips are chosen
> from those existing examples, but are comparable with the ACPI thermal
> policy.
> 
> While not used for cooling/throttling, also add the other thermal zones
> for temperature reporting purposes.
> 
> Enable thermal-monitor mode for all 7 channels in the ADC.
> 
> Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>

Reviewed-by: Abel Vesa <abel.vesa@oss.qualcomm.com>

Re: [PATCH 1/3] arm64: dts: qcom: hamoa-pmics: Mark pmk8550_vadc thermal sensor provider

[Abel Vesa]

On 26-08-30 21:02:02, Bjorn Andersson wrote:
> The PMK8550 VADC is typically providing thermal measurements based on
> on-board thermistors, define #thermal-sensor-cells to allow referencing
> it as such.
> 
> Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>

Reviewed-by: Abel Vesa <abel.vesa@oss.qualcomm.com>

Re: [PATCH 2/3] arm64: dts: qcom: hamoa-crd: Add thermal control

[Stephan Gerhold]

On Sun, Aug 30, 2026 at 09:02:03PM +0000, Bjorn Andersson wrote:
> The "limits" hardware performs rapid thermal management of the CPU
> cores, but during prolonged CPU usage the system's overall temperature
> need to be further managed by software.
> 
> The reference design provides seven "system thermistors", connected to
> the PMK8550 VADC. Particularly interesting is the "keyboard hotspot
> thermistor", which is wired up to sys_therm1.
> 
> Use this to throttle the CPUs, in the same way that we're throttling
> previous generation laptops based on "skin-temp". The trips are chosen
> from those existing examples, but are comparable with the ACPI thermal
> policy.
> 

In general, following the ACPI thermal policy as close as possible is
better than following existing examples. Most X1E-based devices use
hybrid active/passive cooling, with the fan controlled independently by
the EC. If you start throttling even just 1-2°C before the EC reaches
its highest fan trip point, it will result in bad performance. Linux
will try to keep the temperature below the specified temperature, and
the EC will never fully ramp up the fan.

This is what I determined from the CRD ACPI tables last year:
https://github.com/stephan-gh/linux/commit/24f053436ec2eaf70968803adfa8c17905e53cae.patch

The fact that GPU is only throttled based on back-thermal is a little
odd, but this is what the ACPI tables specified back then as far as
I could tell (maybe it was fixed since then).

Your changes seem close enough to not cause the performance problem
I mentioned above, although I think it would be worth setting a good
examples for others to follow.

> While not used for cooling/throttling, also add the other thermal zones
> for temperature reporting purposes.
> 
> Enable thermal-monitor mode for all 7 channels in the ADC.
> 
> Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
> ---
>  arch/arm64/boot/dts/qcom/x1e80100-crd.dts | 116 ++++++++++++++++++++++++++++++
>  1 file changed, 116 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/x1e80100-crd.dts b/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
> index 429deffcf3e9..065af18357d7 100644
> --- a/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
> +++ b/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
> @@ -11,6 +11,92 @@
>  / {
>  	model = "Qualcomm Technologies, Inc. X1E80100 CRD";
>  	compatible = "qcom,x1e80100-crd", "qcom,x1e80100";
> +
> +	thermal-zones {
> +		soc-thermal {
> +			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX1_GPIO_100K_PU(1)>;
> +		};
> +
> +		keyboard-thermal {
> +			polling-delay-passive = <250>;
> +
> +			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX2_GPIO_100K_PU(1)>;
> +
> +			trips {
> +				skin_alert0: trip-point0 {
> +					temperature = <55000>;
> +					hysteresis = <1000>;
> +					type = "passive";
> +				};
> +
> +				skin_alert1: trip-point1 {
> +					temperature = <58000>;
> +					hysteresis = <1000>;
> +					type = "passive";
> +				};

What does this second trip point do differently than the first? It has
the same cooling devices. Will it try throttling "harder" than before?

I know sc8280xp-lenovo-thinkpad-x13s.dts has the same, but I'm not
entirely sure what it does there either.

My experience was if you specify 55°C as one passive trip point, then
Linux will try its best to keep it with the specified cooling devices.

> +
> +				skin-crit {
> +					temperature = <73000>;
> +					hysteresis = <1000>;
> +					type = "critical";
> +				};
> +			};
> +
> +			cooling-maps {
> +				map0 {
> +					trip = <&skin_alert0>;
> +					cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&cpu1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&cpu2 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&cpu3 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&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>,
> +							 <&cpu8 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&cpu9 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&cpu10 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&cpu11 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> +				};
> +
> +				map1 {
> +					trip = <&skin_alert1>;
> +					cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&cpu1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&cpu2 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&cpu3 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&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>,
> +							 <&cpu8 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&cpu9 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&cpu10 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> +							 <&cpu11 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> +				};
> +			};
> +		};
> +
> +		backcover-thermal {
> +			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX1_THM_100K_PU(1)>;
> +		};

Should we add throttling here as well to match Windows?

Thanks,
Stephan

Re: [PATCH 2/3] arm64: dts: qcom: hamoa-crd: Add thermal control

[Bjorn Andersson]

On Mon, Aug 31, 2026 at 10:58:56AM +0200, Stephan Gerhold wrote:
> On Sun, Aug 30, 2026 at 09:02:03PM +0000, Bjorn Andersson wrote:
> > The "limits" hardware performs rapid thermal management of the CPU
> > cores, but during prolonged CPU usage the system's overall temperature
> > need to be further managed by software.
> > 
> > The reference design provides seven "system thermistors", connected to
> > the PMK8550 VADC. Particularly interesting is the "keyboard hotspot
> > thermistor", which is wired up to sys_therm1.
> > 
> > Use this to throttle the CPUs, in the same way that we're throttling
> > previous generation laptops based on "skin-temp". The trips are chosen
> > from those existing examples, but are comparable with the ACPI thermal
> > policy.
> > 
> 
> In general, following the ACPI thermal policy as close as possible is
> better than following existing examples. Most X1E-based devices use
> hybrid active/passive cooling, with the fan controlled independently by
> the EC. If you start throttling even just 1-2°C before the EC reaches
> its highest fan trip point, it will result in bad performance. Linux
> will try to keep the temperature below the specified temperature, and
> the EC will never fully ramp up the fan.
> 

That's certainly true. On X13s it was a bit easier as it's passively
cooled, but these things needs to be taken into consideration.

> This is what I determined from the CRD ACPI tables last year:
> https://github.com/stephan-gh/linux/commit/24f053436ec2eaf70968803adfa8c17905e53cae.patch
> 

Why don't you post your patches!? Have I missed it?

> The fact that GPU is only throttled based on back-thermal is a little
> odd, but this is what the ACPI tables specified back then as far as
> I could tell (maybe it was fixed since then).
> 
> Your changes seem close enough to not cause the performance problem
> I mentioned above, although I think it would be worth setting a good
> examples for others to follow.
> 

Sure, I'll compare with ACPI tables and adjust the numbers accordingly.

> > While not used for cooling/throttling, also add the other thermal zones
> > for temperature reporting purposes.
> > 
> > Enable thermal-monitor mode for all 7 channels in the ADC.
> > 
> > Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
> > ---
> >  arch/arm64/boot/dts/qcom/x1e80100-crd.dts | 116 ++++++++++++++++++++++++++++++
> >  1 file changed, 116 insertions(+)
> > 
> > diff --git a/arch/arm64/boot/dts/qcom/x1e80100-crd.dts b/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
> > index 429deffcf3e9..065af18357d7 100644
> > --- a/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
> > +++ b/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
> > @@ -11,6 +11,92 @@
> >  / {
> >  	model = "Qualcomm Technologies, Inc. X1E80100 CRD";
> >  	compatible = "qcom,x1e80100-crd", "qcom,x1e80100";
> > +
> > +	thermal-zones {
> > +		soc-thermal {
> > +			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX1_GPIO_100K_PU(1)>;
> > +		};
> > +
> > +		keyboard-thermal {
> > +			polling-delay-passive = <250>;
> > +
> > +			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX2_GPIO_100K_PU(1)>;
> > +
> > +			trips {
> > +				skin_alert0: trip-point0 {
> > +					temperature = <55000>;
> > +					hysteresis = <1000>;
> > +					type = "passive";
> > +				};
> > +
> > +				skin_alert1: trip-point1 {
> > +					temperature = <58000>;
> > +					hysteresis = <1000>;
> > +					type = "passive";
> > +				};
> 
> What does this second trip point do differently than the first? It has
> the same cooling devices. Will it try throttling "harder" than before?
> 
> I know sc8280xp-lenovo-thinkpad-x13s.dts has the same, but I'm not
> entirely sure what it does there either.
> 
> My experience was if you specify 55°C as one passive trip point, then
> Linux will try its best to keep it with the specified cooling devices.
> 

I didn't dive into this rabbit hole... I'll review and update
accordingly.

> > +
> > +				skin-crit {
> > +					temperature = <73000>;

Your patch has 115C here. That may be what the ACPI tables are saying,
but it seems a bit excessive.

> > +					hysteresis = <1000>;
> > +					type = "critical";
> > +				};
> > +			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&skin_alert0>;
> > +					cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +							 <&cpu1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +							 <&cpu2 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +							 <&cpu3 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +							 <&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>,
> > +							 <&cpu8 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +							 <&cpu9 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +							 <&cpu10 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +							 <&cpu11 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> > +				};
> > +
> > +				map1 {
> > +					trip = <&skin_alert1>;
> > +					cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +							 <&cpu1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +							 <&cpu2 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +							 <&cpu3 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +							 <&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>,
> > +							 <&cpu8 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +							 <&cpu9 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +							 <&cpu10 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > +							 <&cpu11 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> > +				};
> > +			};
> > +		};
> > +
> > +		backcover-thermal {
> > +			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX1_THM_100K_PU(1)>;
> > +		};
> 
> Should we add throttling here as well to match Windows?
> 

Then there are the reports that indicate that we should throttle things
when the SMB temperatures reaches something like 80C, which doesn't seem
to be something represented in the ACPI tables.

I'll do a respin of this and then we can tweak it from there. The
important thing for me is to get some reference in, so we can propagate
this to the consumer devices (NB: which doesn't have the same sys_therm
mapping).

Thanks,
Bjorn

> Thanks,
> Stephan

Re: [PATCH 2/3] arm64: dts: qcom: hamoa-crd: Add thermal control

[Stephan Gerhold]

On Mon, Aug 31, 2026 at 09:20:14AM -0500, Bjorn Andersson wrote:
> On Mon, Aug 31, 2026 at 10:58:56AM +0200, Stephan Gerhold wrote:
> > On Sun, Aug 30, 2026 at 09:02:03PM +0000, Bjorn Andersson wrote:
> > > The "limits" hardware performs rapid thermal management of the CPU
> > > cores, but during prolonged CPU usage the system's overall temperature
> > > need to be further managed by software.
> > > 
> > > The reference design provides seven "system thermistors", connected to
> > > the PMK8550 VADC. Particularly interesting is the "keyboard hotspot
> > > thermistor", which is wired up to sys_therm1.
> > > 
> > > Use this to throttle the CPUs, in the same way that we're throttling
> > > previous generation laptops based on "skin-temp". The trips are chosen
> > > from those existing examples, but are comparable with the ACPI thermal
> > > policy.
> > > 
> > 
> > In general, following the ACPI thermal policy as close as possible is
> > better than following existing examples. Most X1E-based devices use
> > hybrid active/passive cooling, with the fan controlled independently by
> > the EC. If you start throttling even just 1-2°C before the EC reaches
> > its highest fan trip point, it will result in bad performance. Linux
> > will try to keep the temperature below the specified temperature, and
> > the EC will never fully ramp up the fan.
> > 
> 
> That's certainly true. On X13s it was a bit easier as it's passively
> cooled, but these things needs to be taken into consideration.
> 
> > This is what I determined from the CRD ACPI tables last year:
> > https://github.com/stephan-gh/linux/commit/24f053436ec2eaf70968803adfa8c17905e53cae.patch
> > 
> 
> Why don't you post your patches!? Have I missed it?
>

No, you haven't missed it. I wanted to send them back when I wrote them
(early 2025), but unfortunately the PMIC5 Gen3 ADC patches then blocked
sending it for almost 1.5 years... :/

I lost track of the long ongoing series at some point and nowadays
I don't even have a CRD to test on anymore, that's why my patch is sadly
stuck in the archive.
 
> > The fact that GPU is only throttled based on back-thermal is a little
> > odd, but this is what the ACPI tables specified back then as far as
> > I could tell (maybe it was fixed since then).
> > 
> > Your changes seem close enough to not cause the performance problem
> > I mentioned above, although I think it would be worth setting a good
> > examples for others to follow.
> > 
> 
> Sure, I'll compare with ACPI tables and adjust the numbers accordingly.
> 

Thanks!

As far as I remember, ACPI has separate thresholds for each of the EC
fan profiles (see [1]). I don't think we can model dynamic temperature
thresholds in the DT, so we'll have to pick some default. IIRC the
default is "best performance without charger", which - back then - was
the 326 kelvin (~53°C) I used in my patch.

[1]: https://lore.kernel.org/linux-arm-msm/20260728-ec_add_more_commands-v1-3-771abd65ee1a@oss.qualcomm.com/

> > > While not used for cooling/throttling, also add the other thermal zones
> > > for temperature reporting purposes.
> > > 
> > > Enable thermal-monitor mode for all 7 channels in the ADC.
> > > 
> > > Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
> > > ---
> > >  arch/arm64/boot/dts/qcom/x1e80100-crd.dts | 116 ++++++++++++++++++++++++++++++
> > >  1 file changed, 116 insertions(+)
> > > 
> > > diff --git a/arch/arm64/boot/dts/qcom/x1e80100-crd.dts b/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
> > > index 429deffcf3e9..065af18357d7 100644
> > > --- a/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
> > > +++ b/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
> > > @@ -11,6 +11,92 @@
> > >  / {
> > >  	model = "Qualcomm Technologies, Inc. X1E80100 CRD";
> > >  	compatible = "qcom,x1e80100-crd", "qcom,x1e80100";
> > > +
> > > +	thermal-zones {
> > > +		soc-thermal {
> > > +			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX1_GPIO_100K_PU(1)>;
> > > +		};
> > > +
> > > +		keyboard-thermal {
> > > +			polling-delay-passive = <250>;
> > > +
> > > +			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX2_GPIO_100K_PU(1)>;
> > > +
> > > +			trips {
> > > +				skin_alert0: trip-point0 {
> > > +					temperature = <55000>;
> > > +					hysteresis = <1000>;
> > > +					type = "passive";
> > > +				};
> > > +
> > > +				skin_alert1: trip-point1 {
> > > +					temperature = <58000>;
> > > +					hysteresis = <1000>;
> > > +					type = "passive";
> > > +				};
> > 
> > What does this second trip point do differently than the first? It has
> > the same cooling devices. Will it try throttling "harder" than before?
> > 
> > I know sc8280xp-lenovo-thinkpad-x13s.dts has the same, but I'm not
> > entirely sure what it does there either.
> > 
> > My experience was if you specify 55°C as one passive trip point, then
> > Linux will try its best to keep it with the specified cooling devices.
> > 
> 
> I didn't dive into this rabbit hole... I'll review and update
> accordingly.
> 

Thanks!

> > > +
> > > +				skin-crit {
> > > +					temperature = <73000>;
> 
> Your patch has 115C here. That may be what the ACPI tables are saying,
> but it seems a bit excessive.
> 

I agree, feel free to change that.

> > > +					hysteresis = <1000>;
> > > +					type = "critical";
> > > +				};
> > > +			};
> > > +
> > > +			cooling-maps {
> > > +				map0 {
> > > +					trip = <&skin_alert0>;
> > > +					cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > +							 <&cpu1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > +							 <&cpu2 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > +							 <&cpu3 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > +							 <&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>,
> > > +							 <&cpu8 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > +							 <&cpu9 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > +							 <&cpu10 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > +							 <&cpu11 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> > > +				};
> > > +
> > > +				map1 {
> > > +					trip = <&skin_alert1>;
> > > +					cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > +							 <&cpu1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > +							 <&cpu2 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > +							 <&cpu3 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > +							 <&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>,
> > > +							 <&cpu8 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > +							 <&cpu9 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > +							 <&cpu10 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > +							 <&cpu11 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> > > +				};
> > > +			};
> > > +		};
> > > +
> > > +		backcover-thermal {
> > > +			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX1_THM_100K_PU(1)>;
> > > +		};
> > 
> > Should we add throttling here as well to match Windows?
> > 
> 
> Then there are the reports that indicate that we should throttle things
> when the SMB temperatures reaches something like 80C, which doesn't seem
> to be something represented in the ACPI tables.
> 

Windows has quite some extra logic in the PEP driver that does
additional fine-grained throttling based on PMIC die temperatures,
battery current, power source / battery percentage and other factors.
Unfortunately, I never fully understood how that works, but it may be
handled in there.

> I'll do a respin of this and then we can tweak it from there. The
> important thing for me is to get some reference in, so we can propagate
> this to the consumer devices (NB: which doesn't have the same sys_therm
> mapping).
> 

Thanks!

I have been working on finishing up my corresponding patch for the T14s
(which is something I can still test unlike the CRD). That one is
unfortunately currently stuck because the SYS_THERMx mapping really is
different from the CRD and even the schematics are not sufficient to
understand where each sensor is located. The mapping seems to be
different from the CRD, unfortunately.

The ACPI side is also extra tricky because it takes the thermal
thresholds for the thermal zones through some lookup table in a random
firmware memory region, which is also applied depending on the selected
fan profile (for the T14s: "low power", "balanced", "performance").
I had some luck with using PowerShell on Windows to obtain the computed
ACPI values using

  Get-CimInstance -Namespace "root/wmi" -ClassName MSAcpi_ThermalZoneTemperature

With that I could see the thresholds (PassiveTripPoint) changing when I
change the power profile in Windows.

For fun I had LLM create this PowerShell script that directly outputs DT
snippets, although unfortunately the missing part is actually mapping
the thermal zones to their purpose (right now it outputs zones like
qcom0658-1-0-thermal or even just tz73-0-thermal).

Just sharing it for reference below.

Thanks,
Stephan

---
<#
.SYNOPSIS
    Exports Windows WMI MSAcpi_ThermalZoneTemperature instances to Linux Devicetree (DTS) format.

.DESCRIPTION
    Queries the 'root\wmi' namespace for ACPI thermal zone instances and translates
    temperatures, passive/active/critical trip points, and sampling rates into Linux
    kernel thermal zone DTS nodes.

.PARAMETER OutputFile
    Optional file path to save the generated DTS nodes. If omitted, prints directly to stdout.

.EXAMPLE
    .\Convert-AcpiToDts.ps1

.EXAMPLE
    .\Convert-AcpiToDts.ps1 -OutputFile "thermal_zones.dtsi"
#>
[CmdletBinding()]
param (
    [Parameter(Mandatory = $false, Position = 0)]
    [string]$OutputFile
)

function ConvertTo-Millicelsius ([uint32]$tenthsKelvin) {
    # ACPI trip points of 0, >= 65535 (0xFFFF), or <= 2732 (<= 0°C) are uninitialized/disabled
    if ($tenthsKelvin -le 2732 -or $tenthsKelvin -ge 65535) {
        return $null
    }
    return [long]($tenthsKelvin * 100) - 273150
}

function Get-DTNames ([string]$instanceName) {
    # Sanitize instance name (e.g. "ACPI\QCOM0658\0_0" -> "qcom0658-0-0")
    $parts = $instanceName -split '\\'
    if ($parts.Count -ge 3) {
        if ($parts[1] -ieq "ThermalZone") {
            $raw = $parts[2]
        } else {
            $raw = "$($parts[1])-$($parts[2])"
        }
    } else {
        $raw = $parts[-1]
    }

    $cleanNode = ($raw.ToLower() -replace '_', '-' -replace '[^a-z0-9-]', '') -replace '-thermal$', ''
    $cleanLabel = $cleanNode -replace '-', '_'

    return @{
        NodeName  = "${cleanNode}-thermal"
        BaseName  = $cleanNode
        LabelName = $cleanLabel
    }
}

# Fetch CIM instances safely into an array
$zones = @(Get-CimInstance -Namespace "root/wmi" -ClassName MSAcpi_ThermalZoneTemperature -ErrorAction SilentlyContinue)

if ($zones.Count -eq 0) {
    Write-Error "No MSAcpi_ThermalZoneTemperature instances found in root\wmi."
    return
}

$dtsNodes = [System.Collections.Generic.List[string]]::new()

foreach ($zone in $zones) {
    $names     = Get-DTNames $zone.InstanceName
    $nodeName  = $names.NodeName
    $baseName  = $names.BaseName
    $labelName = $names.LabelName

    # Check for passive trip point
    $psvMC      = ConvertTo-Millicelsius $zone.PassiveTripPoint
    $hasPassive = ($null -ne $psvMC)

    # Collect valid trip points
    $tripsList = [System.Collections.Generic.List[string]]::new()
    $tripIndex = 0

    # 1. Passive Trip Point (_PSV)
    if ($hasPassive) {
        $tripsList.Add("        ${labelName}_alert${tripIndex}: trip-point${tripIndex} {")
        $tripsList.Add("            temperature = <${psvMC}>;")
        $tripsList.Add("            hysteresis = <1000>;")
        $tripsList.Add("            type = `"passive`";")
        $tripsList.Add("        };")
        $tripIndex++
    }

    # 2. Active Trip Points (_AC0.._ACx)
    if ($zone.ActiveTripPointCount -gt 0 -and $zone.ActiveTripPoint) {
        for ($i = 0; $i -lt $zone.ActiveTripPointCount; $i++) {
            $acMC = ConvertTo-Millicelsius $zone.ActiveTripPoint[$i]
            if ($null -ne $acMC) {
                $tripsList.Add("        ${labelName}_active${i}: trip-point${tripIndex} {")
                $tripsList.Add("            temperature = <${acMC}>;")
                $tripsList.Add("            hysteresis = <1000>;")
                $tripsList.Add("            type = `"active`";")
                $tripsList.Add("        };")
                $tripIndex++
            }
        }
    }

    # 3. Critical Trip Point (_CRT)
    $crtMC = ConvertTo-Millicelsius $zone.CriticalTripPoint
    if ($null -ne $crtMC) {
        $tripsList.Add("        ${baseName}-critical {")
        $tripsList.Add("            temperature = <${crtMC}>;")
        $tripsList.Add("            hysteresis = <1000>;")
        $tripsList.Add("            type = `"critical`";")
        $tripsList.Add("        };")
    }

    # Assemble thermal zone node
    $nodeLines = [System.Collections.Generic.List[string]]::new()
    $nodeLines.Add("${nodeName} {")
    $nodeLines.Add("    thermal-sensors = <&placeholder_sensor>; /* Replace with target sensor phandle */")

    # Include polling-delay-passive ONLY if a passive trip point exists
    if ($hasPassive) {
        $pollingPassiveMs = if ($zone.SamplingPeriod -gt 0) { $zone.SamplingPeriod * 100 } else { 1000 }
        $nodeLines.Add("    polling-delay-passive = <${pollingPassiveMs}>;")
    }

    # Include trips {} block ONLY if trip points exist
    if ($tripsList.Count -gt 0) {
        $nodeLines.Add("")
        $nodeLines.Add("    trips {")
        foreach ($line in $tripsList) {
            $nodeLines.Add($line)
        }
        $nodeLines.Add("    };")
    }

    $nodeLines.Add("};")
    $dtsNodes.Add(($nodeLines -join "`n"))
}

$finalOutput = $dtsNodes -join "`n`n"

if (-not [string]::IsNullOrWhiteSpace($OutputFile)) {
    $finalOutput | Out-File -FilePath $OutputFile -Encoding utf8
    Write-Host "Successfully exported Devicetree thermal zones to: $OutputFile" -ForegroundColor Green
} else {
    $finalOutput
}

Re: [PATCH 2/3] arm64: dts: qcom: hamoa-crd: Add thermal control

[Bjorn Andersson]

On Mon, Aug 31, 2026 at 06:11:14PM +0200, Stephan Gerhold wrote:
> On Mon, Aug 31, 2026 at 09:20:14AM -0500, Bjorn Andersson wrote:
> > On Mon, Aug 31, 2026 at 10:58:56AM +0200, Stephan Gerhold wrote:
> > > On Sun, Aug 30, 2026 at 09:02:03PM +0000, Bjorn Andersson wrote:
> > > > The "limits" hardware performs rapid thermal management of the CPU
> > > > cores, but during prolonged CPU usage the system's overall temperature
> > > > need to be further managed by software.
> > > > 
> > > > The reference design provides seven "system thermistors", connected to
> > > > the PMK8550 VADC. Particularly interesting is the "keyboard hotspot
> > > > thermistor", which is wired up to sys_therm1.
> > > > 
> > > > Use this to throttle the CPUs, in the same way that we're throttling
> > > > previous generation laptops based on "skin-temp". The trips are chosen
> > > > from those existing examples, but are comparable with the ACPI thermal
> > > > policy.
> > > > 
> > > 
> > > In general, following the ACPI thermal policy as close as possible is
> > > better than following existing examples. Most X1E-based devices use
> > > hybrid active/passive cooling, with the fan controlled independently by
> > > the EC. If you start throttling even just 1-2°C before the EC reaches
> > > its highest fan trip point, it will result in bad performance. Linux
> > > will try to keep the temperature below the specified temperature, and
> > > the EC will never fully ramp up the fan.
> > > 
> > 
> > That's certainly true. On X13s it was a bit easier as it's passively
> > cooled, but these things needs to be taken into consideration.
> > 
> > > This is what I determined from the CRD ACPI tables last year:
> > > https://github.com/stephan-gh/linux/commit/24f053436ec2eaf70968803adfa8c17905e53cae.patch
> > > 
> > 
> > Why don't you post your patches!? Have I missed it?
> >
> 
> No, you haven't missed it. I wanted to send them back when I wrote them
> (early 2025), but unfortunately the PMIC5 Gen3 ADC patches then blocked
> sending it for almost 1.5 years... :/
> 

I agree, that took way too long - and we lost all momentum on the
continuation thereof (i.e. this patch...)

> I lost track of the long ongoing series at some point and nowadays
> I don't even have a CRD to test on anymore, that's why my patch is sadly
> stuck in the archive.
>  

That unfortunately makes sense.

> > > The fact that GPU is only throttled based on back-thermal is a little
> > > odd, but this is what the ACPI tables specified back then as far as
> > > I could tell (maybe it was fixed since then).
> > > 
> > > Your changes seem close enough to not cause the performance problem
> > > I mentioned above, although I think it would be worth setting a good
> > > examples for others to follow.
> > > 
> > 
> > Sure, I'll compare with ACPI tables and adjust the numbers accordingly.
> > 
> 
> Thanks!
> 
> As far as I remember, ACPI has separate thresholds for each of the EC
> fan profiles (see [1]). I don't think we can model dynamic temperature
> thresholds in the DT, so we'll have to pick some default. IIRC the
> default is "best performance without charger", which - back then - was
> the 326 kelvin (~53°C) I used in my patch.
> 

There's another level of dynamic thermal management needed for that.
It's my understanding that thermald is expected to fill that gap...

> [1]: https://lore.kernel.org/linux-arm-msm/20260728-ec_add_more_commands-v1-3-771abd65ee1a@oss.qualcomm.com/
> 
> > > > While not used for cooling/throttling, also add the other thermal zones
> > > > for temperature reporting purposes.
> > > > 
> > > > Enable thermal-monitor mode for all 7 channels in the ADC.
> > > > 
> > > > Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
> > > > ---
> > > >  arch/arm64/boot/dts/qcom/x1e80100-crd.dts | 116 ++++++++++++++++++++++++++++++
> > > >  1 file changed, 116 insertions(+)
> > > > 
> > > > diff --git a/arch/arm64/boot/dts/qcom/x1e80100-crd.dts b/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
> > > > index 429deffcf3e9..065af18357d7 100644
> > > > --- a/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
> > > > +++ b/arch/arm64/boot/dts/qcom/x1e80100-crd.dts
> > > > @@ -11,6 +11,92 @@
> > > >  / {
> > > >  	model = "Qualcomm Technologies, Inc. X1E80100 CRD";
> > > >  	compatible = "qcom,x1e80100-crd", "qcom,x1e80100";
> > > > +
> > > > +	thermal-zones {
> > > > +		soc-thermal {
> > > > +			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX1_GPIO_100K_PU(1)>;
> > > > +		};
> > > > +
> > > > +		keyboard-thermal {
> > > > +			polling-delay-passive = <250>;
> > > > +
> > > > +			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX2_GPIO_100K_PU(1)>;
> > > > +
> > > > +			trips {
> > > > +				skin_alert0: trip-point0 {
> > > > +					temperature = <55000>;
> > > > +					hysteresis = <1000>;
> > > > +					type = "passive";
> > > > +				};
> > > > +
> > > > +				skin_alert1: trip-point1 {
> > > > +					temperature = <58000>;
> > > > +					hysteresis = <1000>;
> > > > +					type = "passive";
> > > > +				};
> > > 
> > > What does this second trip point do differently than the first? It has
> > > the same cooling devices. Will it try throttling "harder" than before?
> > > 
> > > I know sc8280xp-lenovo-thinkpad-x13s.dts has the same, but I'm not
> > > entirely sure what it does there either.
> > > 
> > > My experience was if you specify 55°C as one passive trip point, then
> > > Linux will try its best to keep it with the specified cooling devices.
> > > 
> > 
> > I didn't dive into this rabbit hole... I'll review and update
> > accordingly.
> > 
> 
> Thanks!
> 
> > > > +
> > > > +				skin-crit {
> > > > +					temperature = <73000>;
> > 
> > Your patch has 115C here. That may be what the ACPI tables are saying,
> > but it seems a bit excessive.
> > 
> 
> I agree, feel free to change that.
> 
> > > > +					hysteresis = <1000>;
> > > > +					type = "critical";
> > > > +				};
> > > > +			};
> > > > +
> > > > +			cooling-maps {
> > > > +				map0 {
> > > > +					trip = <&skin_alert0>;
> > > > +					cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > > +							 <&cpu1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > > +							 <&cpu2 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > > +							 <&cpu3 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > > +							 <&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>,
> > > > +							 <&cpu8 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > > +							 <&cpu9 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > > +							 <&cpu10 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > > +							 <&cpu11 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> > > > +				};
> > > > +
> > > > +				map1 {
> > > > +					trip = <&skin_alert1>;
> > > > +					cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > > +							 <&cpu1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > > +							 <&cpu2 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > > +							 <&cpu3 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > > +							 <&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>,
> > > > +							 <&cpu8 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > > +							 <&cpu9 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > > +							 <&cpu10 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> > > > +							 <&cpu11 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> > > > +				};
> > > > +			};
> > > > +		};
> > > > +
> > > > +		backcover-thermal {
> > > > +			thermal-sensors = <&pmk8550_vadc ADC5_GEN3_AMUX1_THM_100K_PU(1)>;
> > > > +		};
> > > 
> > > Should we add throttling here as well to match Windows?
> > > 
> > 
> > Then there are the reports that indicate that we should throttle things
> > when the SMB temperatures reaches something like 80C, which doesn't seem
> > to be something represented in the ACPI tables.
> > 
> 
> Windows has quite some extra logic in the PEP driver that does
> additional fine-grained throttling based on PMIC die temperatures,
> battery current, power source / battery percentage and other factors.
> Unfortunately, I never fully understood how that works, but it may be
> handled in there.
> 

Yes, there are additional layers there, both in PEP and Windows.

> > I'll do a respin of this and then we can tweak it from there. The
> > important thing for me is to get some reference in, so we can propagate
> > this to the consumer devices (NB: which doesn't have the same sys_therm
> > mapping).
> > 
> 
> Thanks!
> 
> I have been working on finishing up my corresponding patch for the T14s
> (which is something I can still test unlike the CRD). That one is
> unfortunately currently stuck because the SYS_THERMx mapping really is
> different from the CRD and even the schematics are not sufficient to
> understand where each sensor is located. The mapping seems to be
> different from the CRD, unfortunately.
> 

Yes, each design have their own sensor setup, but at least if we land
this we have a reference for the mechanism.

Would certainly be nice to get the T14s pieces landed though. And I
would consider it to be perfectly fine to not fully replicate the
Windows/ACPI setup - since we don't have the additional layers.

I did peek at the Dell XPS13 DSDT and I see the same problem there.

> The ACPI side is also extra tricky because it takes the thermal
> thresholds for the thermal zones through some lookup table in a random
> firmware memory region, which is also applied depending on the selected
> fan profile (for the T14s: "low power", "balanced", "performance").

I think we need to just treat the current ACPI situation as
"inspiration", do some measurements and provide something that seems to
work for DT/Linux.

And if nothing else, it's going to be way better than what we have now
(i.e. nothing).

> I had some luck with using PowerShell on Windows to obtain the computed
> ACPI values using
> 
>   Get-CimInstance -Namespace "root/wmi" -ClassName MSAcpi_ThermalZoneTemperature
> 
> With that I could see the thresholds (PassiveTripPoint) changing when I
> change the power profile in Windows.
> 
> For fun I had LLM create this PowerShell script that directly outputs DT
> snippets, although unfortunately the missing part is actually mapping
> the thermal zones to their purpose (right now it outputs zones like
> qcom0658-1-0-thermal or even just tz73-0-thermal).
> 
> Just sharing it for reference below.
> 

Thanks for sharing.

Thanks,
Bjorn

> Thanks,
> Stephan
> 
> ---
> <#
> .SYNOPSIS
>     Exports Windows WMI MSAcpi_ThermalZoneTemperature instances to Linux Devicetree (DTS) format.
> 
> .DESCRIPTION
>     Queries the 'root\wmi' namespace for ACPI thermal zone instances and translates
>     temperatures, passive/active/critical trip points, and sampling rates into Linux
>     kernel thermal zone DTS nodes.
> 
> .PARAMETER OutputFile
>     Optional file path to save the generated DTS nodes. If omitted, prints directly to stdout.
> 
> .EXAMPLE
>     .\Convert-AcpiToDts.ps1
> 
> .EXAMPLE
>     .\Convert-AcpiToDts.ps1 -OutputFile "thermal_zones.dtsi"
> #>
> [CmdletBinding()]
> param (
>     [Parameter(Mandatory = $false, Position = 0)]
>     [string]$OutputFile
> )
> 
> function ConvertTo-Millicelsius ([uint32]$tenthsKelvin) {
>     # ACPI trip points of 0, >= 65535 (0xFFFF), or <= 2732 (<= 0°C) are uninitialized/disabled
>     if ($tenthsKelvin -le 2732 -or $tenthsKelvin -ge 65535) {
>         return $null
>     }
>     return [long]($tenthsKelvin * 100) - 273150
> }
> 
> function Get-DTNames ([string]$instanceName) {
>     # Sanitize instance name (e.g. "ACPI\QCOM0658\0_0" -> "qcom0658-0-0")
>     $parts = $instanceName -split '\\'
>     if ($parts.Count -ge 3) {
>         if ($parts[1] -ieq "ThermalZone") {
>             $raw = $parts[2]
>         } else {
>             $raw = "$($parts[1])-$($parts[2])"
>         }
>     } else {
>         $raw = $parts[-1]
>     }
> 
>     $cleanNode = ($raw.ToLower() -replace '_', '-' -replace '[^a-z0-9-]', '') -replace '-thermal$', ''
>     $cleanLabel = $cleanNode -replace '-', '_'
> 
>     return @{
>         NodeName  = "${cleanNode}-thermal"
>         BaseName  = $cleanNode
>         LabelName = $cleanLabel
>     }
> }
> 
> # Fetch CIM instances safely into an array
> $zones = @(Get-CimInstance -Namespace "root/wmi" -ClassName MSAcpi_ThermalZoneTemperature -ErrorAction SilentlyContinue)
> 
> if ($zones.Count -eq 0) {
>     Write-Error "No MSAcpi_ThermalZoneTemperature instances found in root\wmi."
>     return
> }
> 
> $dtsNodes = [System.Collections.Generic.List[string]]::new()
> 
> foreach ($zone in $zones) {
>     $names     = Get-DTNames $zone.InstanceName
>     $nodeName  = $names.NodeName
>     $baseName  = $names.BaseName
>     $labelName = $names.LabelName
> 
>     # Check for passive trip point
>     $psvMC      = ConvertTo-Millicelsius $zone.PassiveTripPoint
>     $hasPassive = ($null -ne $psvMC)
> 
>     # Collect valid trip points
>     $tripsList = [System.Collections.Generic.List[string]]::new()
>     $tripIndex = 0
> 
>     # 1. Passive Trip Point (_PSV)
>     if ($hasPassive) {
>         $tripsList.Add("        ${labelName}_alert${tripIndex}: trip-point${tripIndex} {")
>         $tripsList.Add("            temperature = <${psvMC}>;")
>         $tripsList.Add("            hysteresis = <1000>;")
>         $tripsList.Add("            type = `"passive`";")
>         $tripsList.Add("        };")
>         $tripIndex++
>     }
> 
>     # 2. Active Trip Points (_AC0.._ACx)
>     if ($zone.ActiveTripPointCount -gt 0 -and $zone.ActiveTripPoint) {
>         for ($i = 0; $i -lt $zone.ActiveTripPointCount; $i++) {
>             $acMC = ConvertTo-Millicelsius $zone.ActiveTripPoint[$i]
>             if ($null -ne $acMC) {
>                 $tripsList.Add("        ${labelName}_active${i}: trip-point${tripIndex} {")
>                 $tripsList.Add("            temperature = <${acMC}>;")
>                 $tripsList.Add("            hysteresis = <1000>;")
>                 $tripsList.Add("            type = `"active`";")
>                 $tripsList.Add("        };")
>                 $tripIndex++
>             }
>         }
>     }
> 
>     # 3. Critical Trip Point (_CRT)
>     $crtMC = ConvertTo-Millicelsius $zone.CriticalTripPoint
>     if ($null -ne $crtMC) {
>         $tripsList.Add("        ${baseName}-critical {")
>         $tripsList.Add("            temperature = <${crtMC}>;")
>         $tripsList.Add("            hysteresis = <1000>;")
>         $tripsList.Add("            type = `"critical`";")
>         $tripsList.Add("        };")
>     }
> 
>     # Assemble thermal zone node
>     $nodeLines = [System.Collections.Generic.List[string]]::new()
>     $nodeLines.Add("${nodeName} {")
>     $nodeLines.Add("    thermal-sensors = <&placeholder_sensor>; /* Replace with target sensor phandle */")
> 
>     # Include polling-delay-passive ONLY if a passive trip point exists
>     if ($hasPassive) {
>         $pollingPassiveMs = if ($zone.SamplingPeriod -gt 0) { $zone.SamplingPeriod * 100 } else { 1000 }
>         $nodeLines.Add("    polling-delay-passive = <${pollingPassiveMs}>;")
>     }
> 
>     # Include trips {} block ONLY if trip points exist
>     if ($tripsList.Count -gt 0) {
>         $nodeLines.Add("")
>         $nodeLines.Add("    trips {")
>         foreach ($line in $tripsList) {
>             $nodeLines.Add($line)
>         }
>         $nodeLines.Add("    };")
>     }
> 
>     $nodeLines.Add("};")
>     $dtsNodes.Add(($nodeLines -join "`n"))
> }
> 
> $finalOutput = $dtsNodes -join "`n`n"
> 
> if (-not [string]::IsNullOrWhiteSpace($OutputFile)) {
>     $finalOutput | Out-File -FilePath $OutputFile -Encoding utf8
>     Write-Host "Successfully exported Devicetree thermal zones to: $OutputFile" -ForegroundColor Green
> } else {
>     $finalOutput
> }

Re: [PATCH 2/3] arm64: dts: qcom: hamoa-crd: Add thermal control

[Stephan Gerhold]

On Mon, Aug 31, 2026 at 01:14:06PM -0500, Bjorn Andersson wrote:
> On Mon, Aug 31, 2026 at 06:11:14PM +0200, Stephan Gerhold wrote:
> > On Mon, Aug 31, 2026 at 09:20:14AM -0500, Bjorn Andersson wrote:
> > > On Mon, Aug 31, 2026 at 10:58:56AM +0200, Stephan Gerhold wrote:
> > > > On Sun, Aug 30, 2026 at 09:02:03PM +0000, Bjorn Andersson wrote:
> [...]
> > I have been working on finishing up my corresponding patch for the T14s
> > (which is something I can still test unlike the CRD). That one is
> > unfortunately currently stuck because the SYS_THERMx mapping really is
> > different from the CRD and even the schematics are not sufficient to
> > understand where each sensor is located. The mapping seems to be
> > different from the CRD, unfortunately.
> > 
> 
> Yes, each design have their own sensor setup, but at least if we land
> this we have a reference for the mechanism.
> 
> Would certainly be nice to get the T14s pieces landed though. And I
> would consider it to be perfectly fine to not fully replicate the
> Windows/ACPI setup - since we don't have the additional layers.
>

Indeed. I tried contacting Mark Pearson a few weeks ago to get some more
details (since he offered his help in [1]), but unfortunately he did not
reply so far.

I'll recheck the info I've already guessed so far and will see if this
is sufficient to add some basic thermal throttling.

[1]: https://lore.kernel.org/linux-arm-msm/ea0b329e-ab3e-4655-8f27-e7a74784302a@app.fastmail.com/

> I did peek at the Dell XPS13 DSDT and I see the same problem there.
> 
> > The ACPI side is also extra tricky because it takes the thermal
> > thresholds for the thermal zones through some lookup table in a random
> > firmware memory region, which is also applied depending on the selected
> > fan profile (for the T14s: "low power", "balanced", "performance").
> 
> I think we need to just treat the current ACPI situation as
> "inspiration", do some measurements and provide something that seems to
> work for DT/Linux.
> 
> And if nothing else, it's going to be way better than what we have now
> (i.e. nothing).
> 

Agreed.

Thanks,
Stephan

Re: [PATCH 3/3] arm64: defconfig: Enable PMIC5 Gen3 ADC thermal monitor

[Krzysztof Kozlowski]

On 30/08/2026 23:02, Bjorn Andersson wrote:
> All Hamoa-based devices uses PMIC5 Gen3 ADC connected to thermistors for

"All Qualcomm Hamoa-based devices use Qualcomm PMIC5 ..."

> measuring temperature across the system.
> 
> Enable the Gen3 ADC, and it's associated ADC_TM auxiliary, drivers to

s/Gen3 ADC/Qualcomm PMIC Gen3 ADC/ or something similar

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>

Best regards,
Krzysztof