Re: [PATCH 1/2] arm64: dts: qcom: sm8650: setup cpu thermal with idle on high temperatures

[Neil Armstrong <neil.armstrong@xxxxxxxxxx>]

Hi,

On 07/01/2025 00:39, Bjorn Andersson wrote:
> On Fri, Jan 03, 2025 at 03:38:26PM +0100, Neil Armstrong wrote:
> > On the SM8650, the dynamic clock and voltage scaling (DCVS) is done in an
> > hardware controlled loop using the LMH and EPSS blocks with constraints and
> > OPPs programmed in the board firmware.
> >
> > Since the Hardware does a better job at maintaining the CPUs temperature
> > in an acceptable range by taking in account more parameters like the die
> > characteristics or other factory fused values, it makes no sense to try
> > and reproduce a similar set of constraints with the Linux cpufreq thermal
> > core.
> >
> > In addition, the tsens IP is responsible for monitoring the temperature
> > across the SoC and the current settings will heavily trigger the tsens
> > UP/LOW interrupts if the CPU temperatures reaches the hardware thermal
> > constraints which are currently defined in the DT. And since the CPUs
> > are not hooked in the thermal trip points, the potential interrupts and
> > calculations are a waste of system resources.
> >
> > Instead, set higher temperatures in the CPU trip points, and hook some CPU
> > idle injector with a 100% duty cycle at the highest trip point in the case
> > the hardware DCVS cannot handle the temperature surge, and try our best to
> > avoid reaching the critical temperature trip point which should trigger an
> > inevitable thermal shutdown.
>
> Are you able to hit these higher temperatures? Do you have some test
> case where the idle-injection shows to be successful in blocking us from
> reaching the critical temp?

No, I've been able to test idle-injection and observed a noticeable effect
but I had to set lower trip, do you know how I can easily "block" LMH/EPSS from
scaling down and let the temp go higher ?

> E.g. in X13s (SC8280XP) we opted for relying on LMH/EPSS and define only
> the critical trip for when the hardware fails us.

It's the goal here aswell

> I have no concerns at all about "removing" the 90C trip point, that
> makes total sense to me - let the hardware keep the cores as close to
> max as possible, and then use some slower sensor for keeping the system
> temperature in check (such as the x13s skin sensor).
>
>
> PS. The described behavior should apply to anything SDM845 and newer, so
> I'd like to see this set/document precedence for other platforms.
>
> Regards,
> Bjorn
>
> > Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
> > ---
> >   arch/arm64/boot/dts/qcom/sm8650.dtsi | 274 +++++++++++++++++++++++++++--------
> >   1 file changed, 214 insertions(+), 60 deletions(-)
> >
> > diff --git a/arch/arm64/boot/dts/qcom/sm8650.dtsi b/arch/arm64/boot/dts/qcom/sm8650.dtsi
> > index 25e47505adcb790d09f1d2726386438487255824..448374a32e07151e35727d92fab77356769aea8a 100644
> > --- a/arch/arm64/boot/dts/qcom/sm8650.dtsi
> > +++ b/arch/arm64/boot/dts/qcom/sm8650.dtsi
> > @@ -99,6 +99,13 @@ l3_0: l3-cache {
> >   					cache-unified;
> >   				};
> >   			};
> > +
> > +			cpu0_idle: thermal-idle {
> > +				#cooling-cells = <2>;
> > +				duration-us = <800000>;
> > +				exit-latency-us = <10000>;
> > +			};
> > +
> >   		};
> >   
> >   		cpu1: cpu@100 {
> > @@ -119,6 +126,12 @@ cpu1: cpu@100 {
> >   			qcom,freq-domain = <&cpufreq_hw 0>;
> >   
> >   			#cooling-cells = <2>;
> > +
> > +			cpu1_idle: thermal-idle {
> > +				#cooling-cells = <2>;
> > +				duration-us = <800000>;
> > +				exit-latency-us = <10000>;
> > +			};
> >   		};
> >   
> >   		cpu2: cpu@200 {
> > @@ -146,6 +159,12 @@ l2_200: l2-cache {
> >   				cache-unified;
> >   				next-level-cache = <&l3_0>;
> >   			};
> > +
> > +			cpu2_idle: thermal-idle {
> > +				#cooling-cells = <2>;
> > +				duration-us = <800000>;
> > +				exit-latency-us = <10000>;
> > +			};
> >   		};
> >   
> >   		cpu3: cpu@300 {
> > @@ -166,6 +185,12 @@ cpu3: cpu@300 {
> >   			qcom,freq-domain = <&cpufreq_hw 3>;
> >   
> >   			#cooling-cells = <2>;
> > +
> > +			cpu3_idle: thermal-idle {
> > +				#cooling-cells = <2>;
> > +				duration-us = <800000>;
> > +				exit-latency-us = <10000>;
> > +			};
> >   		};
> >   
> >   		cpu4: cpu@400 {
> > @@ -193,6 +218,12 @@ l2_400: l2-cache {
> >   				cache-unified;
> >   				next-level-cache = <&l3_0>;
> >   			};
> > +
> > +			cpu4_idle: thermal-idle {
> > +				#cooling-cells = <2>;
> > +				duration-us = <800000>;
> > +				exit-latency-us = <10000>;
> > +			};
> >   		};
> >   
> >   		cpu5: cpu@500 {
> > @@ -220,6 +251,12 @@ l2_500: l2-cache {
> >   				cache-unified;
> >   				next-level-cache = <&l3_0>;
> >   			};
> > +
> > +			cpu5_idle: thermal-idle {
> > +				#cooling-cells = <2>;
> > +				duration-us = <800000>;
> > +				exit-latency-us = <10000>;
> > +			};
> >   		};
> >   
> >   		cpu6: cpu@600 {
> > @@ -247,6 +284,12 @@ l2_600: l2-cache {
> >   				cache-unified;
> >   				next-level-cache = <&l3_0>;
> >   			};
> > +
> > +			cpu6_idle: thermal-idle {
> > +				#cooling-cells = <2>;
> > +				duration-us = <800000>;
> > +				exit-latency-us = <10000>;
> > +			};
> >   		};
> >   
> >   		cpu7: cpu@700 {
> > @@ -274,6 +317,12 @@ l2_700: l2-cache {
> >   				cache-unified;
> >   				next-level-cache = <&l3_0>;
> >   			};
> > +
> > +			cpu7_idle: thermal-idle {
> > +				#cooling-cells = <2>;
> > +				duration-us = <800000>;
> > +				exit-latency-us = <10000>;
> > +			};
> >   		};
> >   
> >   		cpu-map {
> > @@ -5752,23 +5801,30 @@ cpu2-top-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu2_top_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu2-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu2_top_alert1>;
> > +					cooling-device = <&cpu2_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		cpu2-bottom-thermal {
> > @@ -5776,23 +5832,30 @@ cpu2-bottom-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu2_bottom_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu2-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu2_bottom_alert1>;
> > +					cooling-device = <&cpu2_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		cpu3-top-thermal {
> > @@ -5800,23 +5863,30 @@ cpu3-top-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu3_top_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu3-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu3_top_alert1>;
> > +					cooling-device = <&cpu3_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		cpu3-bottom-thermal {
> > @@ -5824,23 +5894,30 @@ cpu3-bottom-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu3_bottom_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu3-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu3_bottom_alert1>;
> > +					cooling-device = <&cpu3_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		cpu4-top-thermal {
> > @@ -5848,23 +5925,30 @@ cpu4-top-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu4_top_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu4-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu4_top_alert1>;
> > +					cooling-device = <&cpu4_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		cpu4-bottom-thermal {
> > @@ -5872,23 +5956,30 @@ cpu4-bottom-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu4_bottom_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu4-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu4_bottom_alert1>;
> > +					cooling-device = <&cpu4_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		cpu5-top-thermal {
> > @@ -5896,23 +5987,30 @@ cpu5-top-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu5_top_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu5-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu5_top_alert1>;
> > +					cooling-device = <&cpu5_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		cpu5-bottom-thermal {
> > @@ -5920,23 +6018,30 @@ cpu5-bottom-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu5_bottom_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu5-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu5_bottom_alert1>;
> > +					cooling-device = <&cpu5_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		cpu6-top-thermal {
> > @@ -5944,23 +6049,30 @@ cpu6-top-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu6_top_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu6-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu6_top_alert1>;
> > +					cooling-device = <&cpu6_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		cpu6-bottom-thermal {
> > @@ -5968,23 +6080,30 @@ cpu6-bottom-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu6_bottom_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu6-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu6_bottom_alert1>;
> > +					cooling-device = <&cpu6_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		aoss1-thermal {
> > @@ -6010,23 +6129,30 @@ cpu7-top-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu7_top_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu7-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu7_top_alert1>;
> > +					cooling-device = <&cpu7_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		cpu7-middle-thermal {
> > @@ -6034,23 +6160,30 @@ cpu7-middle-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu7_middle_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu7-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu7_middle_alert1>;
> > +					cooling-device = <&cpu7_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		cpu7-bottom-thermal {
> > @@ -6058,23 +6191,30 @@ cpu7-bottom-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu7_bottom_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu7-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu7_bottom_alert1>;
> > +					cooling-device = <&cpu7_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		cpu0-thermal {
> > @@ -6082,23 +6222,30 @@ cpu0-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu0_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu0-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu0_alert1>;
> > +					cooling-device = <&cpu0_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		cpu1-thermal {
> > @@ -6106,23 +6253,30 @@ cpu1-thermal {
> >   
> >   			trips {
> >   				trip-point0 {
> > -					temperature = <90000>;
> > +					temperature = <108000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> > -				trip-point1 {
> > -					temperature = <95000>;
> > +				cpu1_alert1: trip-point1 {
> > +					temperature = <110000>;
> >   					hysteresis = <2000>;
> >   					type = "passive";
> >   				};
> >   
> >   				cpu1-critical {
> > -					temperature = <110000>;
> > +					temperature = <115000>;
> >   					hysteresis = <1000>;
> >   					type = "critical";
> >   				};
> >   			};
> > +
> > +			cooling-maps {
> > +				map0 {
> > +					trip = <&cpu1_alert1>;
> > +					cooling-device = <&cpu1_idle 100 100>;
> > +				};
> > +			};
> >   		};
> >   
> >   		nsphvx0-thermal {
> >
> > --
> > 2.34.1