On Tue, Jan 07, 2025 at 09:13:18AM +0100, Neil Armstrong wrote:
> 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 ?
>
I don't know how to override that configuration.
> >
> > 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
>
How about simplifying the patch by removing the idle-injection step and
just rely on LMH/EPSS and the "critical" trip (at least until someone
can prove that there's value in the extra mitigation)?
Regards,
Bjorn
> >
> >
> > 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
> > >
>
