Re: [PATCH 4/4] arm64: dts: qcom: ipq9574: add thermal zone nodes

From: Varadarajan Narayanan
Date: Tue May 02 2023 - 04:05:09 EST

On Fri, Apr 28, 2023 at 10:49:34PM +0300, Dmitry Baryshkov wrote:
> On Fri, 28 Apr 2023 at 17:53, Varadarajan Narayanan
> <quic_varada@xxxxxxxxxxx> wrote:
> >
> > This patch adds thermal zone nodes for the various
> > sensors present in IPQ9574
> >
> > Signed-off-by: Praveenkumar I <quic_ipkumar@xxxxxxxxxxx>
> > Signed-off-by: Varadarajan Narayanan <quic_varada@xxxxxxxxxxx>
> > ---
> > arch/arm64/boot/dts/qcom/ipq9574.dtsi | 208 ++++++++++++++++++++++++++++++++++
> > 1 file changed, 208 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/qcom/ipq9574.dtsi b/arch/arm64/boot/dts/qcom/ipq9574.dtsi
> > index 7cd5bdb..a7cb2b4c 100644
> > --- a/arch/arm64/boot/dts/qcom/ipq9574.dtsi
> > +++ b/arch/arm64/boot/dts/qcom/ipq9574.dtsi
> > @@ -947,6 +947,214 @@
> > };
> > };
> >
> > + thermal_zones: thermal-zones {
> > + tsens_tz_sensor3 {
>
> Please provide sensible names for all thermal zones. Please follow the
> examples in other DT files.

Ok.

> > + polling-delay-passive = <0>;
> > + polling-delay = <0>;
> > + thermal-sensors = <&tsens 3>;
> > +
> > + trips {
> > + cpu-critical {
> > + temperature = <125000>;
>
> Can it really go up to 125 °C?

The SoC product requirement is 120°C. It is capable of 125°C.
This was tested inside a thermal chamber and ensured that it
hits 125°C and system reboots at that temperature.

> > + hysteresis = <1000>;
> > + type = "critical";
> > + };
>
> Please provide also a passive trip point, so that the passive cooling
> can be engaged.

The linux kernel cannot take any steps to initiate cooling for
components other than the 4 CPU cores. The f/w that runs on these
IP blocks have to take steps to initiate cooling. Additionally,
the passive temperature for the non-cpu sensors are not
characterised yet and I don't have the values now.

We have these nodes to be able to read the temperature of the
other blocks via the sysfs entry /sys/devices/virtual/thermal/*/temp
Have given the critical trip point so that the setup is rebooted
if the critical temperature is reached.

Have given passive trip point for the CPU core related thermal
nodes (tsens_tz_sensor10, tsens_tz_sensor11, tsens_tz_sensor12
and tsens_tz_sensor13).

If this is not acceptable, please let me know. Will remove the
non-cpu nodes and post a patch with just the CPU entries.

Thanks
Varada

> > + };
> > + };
> > +
> > + tsens_tz_sensor4 {
> > + polling-delay-passive = <0>;
> > + polling-delay = <0>;
> > + thermal-sensors = <&tsens 4>;
> > +
> > + trips {
> > + cpu-critical {
> > + temperature = <125000>;
> > + hysteresis = <1000>;
> > + type = "critical";
> > + };
> > + };
> > + };
> > +
> > + tsens_tz_sensor5 {
> > + polling-delay-passive = <0>;
> > + polling-delay = <0>;
> > + thermal-sensors = <&tsens 5>;
> > +
> > + trips {
> > + cpu-critical {
> > + temperature = <125000>;
> > + hysteresis = <1000>;
> > + type = "critical";
> > + };
> > + };
> > + };
> > +
> > + tsens_tz_sensor6 {
> > + polling-delay-passive = <0>;
> > + polling-delay = <0>;
> > + thermal-sensors = <&tsens 6>;
> > +
> > + trips {
> > + cpu-critical {
> > + temperature = <125000>;
> > + hysteresis = <1000>;
> > + type = "critical";
> > + };
> > + };
> > + };
> > +
> > + tsens_tz_sensor7 {
> > + polling-delay-passive = <0>;
> > + polling-delay = <0>;
> > + thermal-sensors = <&tsens 7>;
> > +
> > + trips {
> > + cpu-critical {
> > + temperature = <125000>;
> > + hysteresis = <1000>;
> > + type = "critical";
> > + };
> > + };
> > + };
> > +
> > + tsens_tz_sensor8 {
> > + polling-delay-passive = <0>;
> > + polling-delay = <0>;
> > + thermal-sensors = <&tsens 8>;
> > +
> > + trips {
> > + cpu-critical {
> > + temperature = <125000>;
> > + hysteresis = <1000>;
> > + type = "critical";
> > + };
> > + };
> > + };
> > +
> > + tsens_tz_sensor9 {
> > + polling-delay-passive = <0>;
> > + polling-delay = <0>;
> > + thermal-sensors = <&tsens 9>;
> > +
> > + trips {
> > + cpu-critical {
> > + temperature = <125000>;
> > + hysteresis = <1000>;
> > + type = "critical";
> > + };
> > + };
> > + };
> > +
> > + tsens_tz_sensor10 {
> > + polling-delay-passive = <0>;
> > + polling-delay = <0>;
> > + thermal-sensors = <&tsens 10>;
> > +
> > + trips {
> > + cpu-critical {
> > + temperature = <120000>;
> > + hysteresis = <10000>;
> > + type = "critical";
> > + };
> > +
> > + cpu-passive {
> > + temperature = <110000>;
> > + hysteresis = <1000>;
> > + type = "passive";
> > + };
> > + };
> > + };
> > +
> > + tsens_tz_sensor11 {
> > + polling-delay-passive = <0>;
> > + polling-delay = <0>;
> > + thermal-sensors = <&tsens 11>;
> > +
> > + trips {
> > + cpu-critical {
> > + temperature = <120000>;
> > + hysteresis = <10000>;
> > + type = "critical";
> > + };
> > +
> > + cpu-passive {
> > + temperature = <110000>;
> > + hysteresis = <1000>;
> > + type = "passive";
> > + };
> > + };
> > + };
> > +
> > + tsens_tz_sensor12 {
> > + polling-delay-passive = <0>;
> > + polling-delay = <0>;
> > + thermal-sensors = <&tsens 12>;
> > +
> > + trips {
> > + cpu-critical {
> > + temperature = <120000>;
> > + hysteresis = <10000>;
> > + type = "critical";
> > + };
> > +
> > + cpu-passive {
> > + temperature = <110000>;
> > + hysteresis = <1000>;
> > + type = "passive";
> > + };
> > + };
> > + };
> > +
> > + tsens_tz_sensor13 {
> > + polling-delay-passive = <0>;
> > + polling-delay = <0>;
> > + thermal-sensors = <&tsens 13>;
> > +
> > + trips {
> > + cpu-critical {
> > + temperature = <120000>;
> > + hysteresis = <10000>;
> > + type = "critical";
> > + };
> > +
> > + cpu-passive {
> > + temperature = <110000>;
> > + hysteresis = <1000>;
> > + type = "passive";
> > + };
> > + };
> > + };
> > +
> > + tsens_tz_sensor14 {
> > + polling-delay-passive = <0>;
> > + polling-delay = <0>;
> > + thermal-sensors = <&tsens 14>;
> > +
> > + trips {
> > + cpu-critical {
> > + temperature = <125000>;
> > + hysteresis = <1000>;
> > + type = "critical";
> > + };
> > + };
> > + };
> > +
> > + tsens_tz_sensor15 {
> > + polling-delay-passive = <0>;
> > + polling-delay = <0>;
> > + thermal-sensors = <&tsens 15>;
> > +
> > + trips {
> > + cpu-critical {
> > + temperature = <125000>;
> > + hysteresis = <1000>;
> > + type = "critical";
> > + };
> > + };
> > + };
> > + };
> > +
> > timer {
> > compatible = "arm,armv8-timer";
> > interrupts = <GIC_PPI 2 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
> > --
> > 2.7.4
> >
>
>
> --
> With best wishes
> Dmitry