| Message ID | 20250110-topic-sm8650-thermal-cpu-idle-v2-2-5787ad79abbb@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | arm64: dts: qcom: sm8650: rework CPU & GPU thermal zones | expand |
On 1/10/2025 4:06 PM, Neil Armstrong wrote: > On the SM8650, the dynamic clock and voltage scaling (DCVS) for the GPU > is done in an hardware controlled loop by the GPU Management Unit (GMU). > > Since the GMU does a better job at maintaining the GPUs temperature in an > acceptable range by taking in account more parameters like the die > characteristics or other internal sensors, it makes no sense to try > and reproduce a similar set of constraints with the Linux devfreq thermal > core. Just FYI, this description is incorrect. SM8650's GMU doesn't do any sort of thermal management. -Akhil. > > Instead, set higher temperatures in the GPU trip points corresponding to > the temperatures provided by Qualcomm in the dowstream source, which will > trigger the devfreq thermal core if the GMU cannot handle the temperature > surge, and try our best to avoid reaching the critical temperature trip > point which should trigger an inevitable thermal shutdown. > > Fixes: 497624ed5506 ("arm64: dts: qcom: sm8650: Throttle the GPU when overheating") > Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org> > --- > arch/arm64/boot/dts/qcom/sm8650.dtsi | 48 ++++++++++++++++++------------------ > 1 file changed, 24 insertions(+), 24 deletions(-) > > diff --git a/arch/arm64/boot/dts/qcom/sm8650.dtsi b/arch/arm64/boot/dts/qcom/sm8650.dtsi > index 95509ce2713d4fcc3dbe0c5cd5827312d5681af4..e9fcf05cb084b7979ecf0f4712fed332e9f4b07a 100644 > --- a/arch/arm64/boot/dts/qcom/sm8650.dtsi > +++ b/arch/arm64/boot/dts/qcom/sm8650.dtsi > @@ -6173,19 +6173,19 @@ map0 { > > trips { > gpu0_alert0: trip-point0 { > - temperature = <85000>; > + temperature = <95000>; > hysteresis = <1000>; > type = "passive"; > }; > > trip-point1 { > - temperature = <90000>; > + temperature = <115000>; > hysteresis = <1000>; > type = "hot"; > }; > > trip-point2 { > - temperature = <110000>; > + temperature = <125000>; > hysteresis = <1000>; > type = "critical"; > }; > @@ -6206,19 +6206,19 @@ map0 { > > trips { > gpu1_alert0: trip-point0 { > - temperature = <85000>; > + temperature = <95000>; > hysteresis = <1000>; > type = "passive"; > }; > > trip-point1 { > - temperature = <90000>; > + temperature = <115000>; > hysteresis = <1000>; > type = "hot"; > }; > > trip-point2 { > - temperature = <110000>; > + temperature = <125000>; > hysteresis = <1000>; > type = "critical"; > }; > @@ -6239,19 +6239,19 @@ map0 { > > trips { > gpu2_alert0: trip-point0 { > - temperature = <85000>; > + temperature = <95000>; > hysteresis = <1000>; > type = "passive"; > }; > > trip-point1 { > - temperature = <90000>; > + temperature = <115000>; > hysteresis = <1000>; > type = "hot"; > }; > > trip-point2 { > - temperature = <110000>; > + temperature = <125000>; > hysteresis = <1000>; > type = "critical"; > }; > @@ -6272,19 +6272,19 @@ map0 { > > trips { > gpu3_alert0: trip-point0 { > - temperature = <85000>; > + temperature = <95000>; > hysteresis = <1000>; > type = "passive"; > }; > > trip-point1 { > - temperature = <90000>; > + temperature = <115000>; > hysteresis = <1000>; > type = "hot"; > }; > > trip-point2 { > - temperature = <110000>; > + temperature = <125000>; > hysteresis = <1000>; > type = "critical"; > }; > @@ -6305,19 +6305,19 @@ map0 { > > trips { > gpu4_alert0: trip-point0 { > - temperature = <85000>; > + temperature = <95000>; > hysteresis = <1000>; > type = "passive"; > }; > > trip-point1 { > - temperature = <90000>; > + temperature = <115000>; > hysteresis = <1000>; > type = "hot"; > }; > > trip-point2 { > - temperature = <110000>; > + temperature = <125000>; > hysteresis = <1000>; > type = "critical"; > }; > @@ -6338,19 +6338,19 @@ map0 { > > trips { > gpu5_alert0: trip-point0 { > - temperature = <85000>; > + temperature = <95000>; > hysteresis = <1000>; > type = "passive"; > }; > > trip-point1 { > - temperature = <90000>; > + temperature = <115000>; > hysteresis = <1000>; > type = "hot"; > }; > > trip-point2 { > - temperature = <110000>; > + temperature = <125000>; > hysteresis = <1000>; > type = "critical"; > }; > @@ -6371,19 +6371,19 @@ map0 { > > trips { > gpu6_alert0: trip-point0 { > - temperature = <85000>; > + temperature = <95000>; > hysteresis = <1000>; > type = "passive"; > }; > > trip-point1 { > - temperature = <90000>; > + temperature = <115000>; > hysteresis = <1000>; > type = "hot"; > }; > > trip-point2 { > - temperature = <110000>; > + temperature = <125000>; > hysteresis = <1000>; > type = "critical"; > }; > @@ -6404,19 +6404,19 @@ map0 { > > trips { > gpu7_alert0: trip-point0 { > - temperature = <85000>; > + temperature = <95000>; > hysteresis = <1000>; > type = "passive"; > }; > > trip-point1 { > - temperature = <90000>; > + temperature = <115000>; > hysteresis = <1000>; > type = "hot"; > }; > > trip-point2 { > - temperature = <110000>; > + temperature = <125000>; > hysteresis = <1000>; > type = "critical"; > }; >
Hi, On 13/01/2025 11:28, Akhil P Oommen wrote: > On 1/10/2025 4:06 PM, Neil Armstrong wrote: >> On the SM8650, the dynamic clock and voltage scaling (DCVS) for the GPU >> is done in an hardware controlled loop by the GPU Management Unit (GMU). >> >> Since the GMU does a better job at maintaining the GPUs temperature in an >> acceptable range by taking in account more parameters like the die >> characteristics or other internal sensors, it makes no sense to try >> and reproduce a similar set of constraints with the Linux devfreq thermal >> core. > > Just FYI, this description is incorrect. SM8650's GMU doesn't do any > sort of thermal management. Ok, thx for confirming this, in our tests the temperature steadily stayed at a max trip point when setting them higher. But perhaps it's a side effect of other mitigations. Are the new trip points still ok ? they are derived from the downstream DT. Thanks, Neil > > -Akhil. > >> >> Instead, set higher temperatures in the GPU trip points corresponding to >> the temperatures provided by Qualcomm in the dowstream source, which will >> trigger the devfreq thermal core if the GMU cannot handle the temperature >> surge, and try our best to avoid reaching the critical temperature trip >> point which should trigger an inevitable thermal shutdown. >> >> Fixes: 497624ed5506 ("arm64: dts: qcom: sm8650: Throttle the GPU when overheating") >> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org> >> --- >> arch/arm64/boot/dts/qcom/sm8650.dtsi | 48 ++++++++++++++++++------------------ >> 1 file changed, 24 insertions(+), 24 deletions(-) >> >> diff --git a/arch/arm64/boot/dts/qcom/sm8650.dtsi b/arch/arm64/boot/dts/qcom/sm8650.dtsi >> index 95509ce2713d4fcc3dbe0c5cd5827312d5681af4..e9fcf05cb084b7979ecf0f4712fed332e9f4b07a 100644 >> --- a/arch/arm64/boot/dts/qcom/sm8650.dtsi >> +++ b/arch/arm64/boot/dts/qcom/sm8650.dtsi >> @@ -6173,19 +6173,19 @@ map0 { >> >> trips { >> gpu0_alert0: trip-point0 { >> - temperature = <85000>; >> + temperature = <95000>; >> hysteresis = <1000>; >> type = "passive"; >> }; >> >> trip-point1 { >> - temperature = <90000>; >> + temperature = <115000>; >> hysteresis = <1000>; >> type = "hot"; >> }; >> >> trip-point2 { >> - temperature = <110000>; >> + temperature = <125000>; >> hysteresis = <1000>; >> type = "critical"; >> }; >> @@ -6206,19 +6206,19 @@ map0 { >> >> trips { >> gpu1_alert0: trip-point0 { >> - temperature = <85000>; >> + temperature = <95000>; >> hysteresis = <1000>; >> type = "passive"; >> }; >> >> trip-point1 { >> - temperature = <90000>; >> + temperature = <115000>; >> hysteresis = <1000>; >> type = "hot"; >> }; >> >> trip-point2 { >> - temperature = <110000>; >> + temperature = <125000>; >> hysteresis = <1000>; >> type = "critical"; >> }; >> @@ -6239,19 +6239,19 @@ map0 { >> >> trips { >> gpu2_alert0: trip-point0 { >> - temperature = <85000>; >> + temperature = <95000>; >> hysteresis = <1000>; >> type = "passive"; >> }; >> >> trip-point1 { >> - temperature = <90000>; >> + temperature = <115000>; >> hysteresis = <1000>; >> type = "hot"; >> }; >> >> trip-point2 { >> - temperature = <110000>; >> + temperature = <125000>; >> hysteresis = <1000>; >> type = "critical"; >> }; >> @@ -6272,19 +6272,19 @@ map0 { >> >> trips { >> gpu3_alert0: trip-point0 { >> - temperature = <85000>; >> + temperature = <95000>; >> hysteresis = <1000>; >> type = "passive"; >> }; >> >> trip-point1 { >> - temperature = <90000>; >> + temperature = <115000>; >> hysteresis = <1000>; >> type = "hot"; >> }; >> >> trip-point2 { >> - temperature = <110000>; >> + temperature = <125000>; >> hysteresis = <1000>; >> type = "critical"; >> }; >> @@ -6305,19 +6305,19 @@ map0 { >> >> trips { >> gpu4_alert0: trip-point0 { >> - temperature = <85000>; >> + temperature = <95000>; >> hysteresis = <1000>; >> type = "passive"; >> }; >> >> trip-point1 { >> - temperature = <90000>; >> + temperature = <115000>; >> hysteresis = <1000>; >> type = "hot"; >> }; >> >> trip-point2 { >> - temperature = <110000>; >> + temperature = <125000>; >> hysteresis = <1000>; >> type = "critical"; >> }; >> @@ -6338,19 +6338,19 @@ map0 { >> >> trips { >> gpu5_alert0: trip-point0 { >> - temperature = <85000>; >> + temperature = <95000>; >> hysteresis = <1000>; >> type = "passive"; >> }; >> >> trip-point1 { >> - temperature = <90000>; >> + temperature = <115000>; >> hysteresis = <1000>; >> type = "hot"; >> }; >> >> trip-point2 { >> - temperature = <110000>; >> + temperature = <125000>; >> hysteresis = <1000>; >> type = "critical"; >> }; >> @@ -6371,19 +6371,19 @@ map0 { >> >> trips { >> gpu6_alert0: trip-point0 { >> - temperature = <85000>; >> + temperature = <95000>; >> hysteresis = <1000>; >> type = "passive"; >> }; >> >> trip-point1 { >> - temperature = <90000>; >> + temperature = <115000>; >> hysteresis = <1000>; >> type = "hot"; >> }; >> >> trip-point2 { >> - temperature = <110000>; >> + temperature = <125000>; >> hysteresis = <1000>; >> type = "critical"; >> }; >> @@ -6404,19 +6404,19 @@ map0 { >> >> trips { >> gpu7_alert0: trip-point0 { >> - temperature = <85000>; >> + temperature = <95000>; >> hysteresis = <1000>; >> type = "passive"; >> }; >> >> trip-point1 { >> - temperature = <90000>; >> + temperature = <115000>; >> hysteresis = <1000>; >> type = "hot"; >> }; >> >> trip-point2 { >> - temperature = <110000>; >> + temperature = <125000>; >> hysteresis = <1000>; >> type = "critical"; >> }; >> >
On 1/13/2025 4:15 PM, Neil Armstrong wrote: > Hi, > > On 13/01/2025 11:28, Akhil P Oommen wrote: >> On 1/10/2025 4:06 PM, Neil Armstrong wrote: >>> On the SM8650, the dynamic clock and voltage scaling (DCVS) for the GPU >>> is done in an hardware controlled loop by the GPU Management Unit (GMU). >>> >>> Since the GMU does a better job at maintaining the GPUs temperature >>> in an >>> acceptable range by taking in account more parameters like the die >>> characteristics or other internal sensors, it makes no sense to try >>> and reproduce a similar set of constraints with the Linux devfreq >>> thermal >>> core. >> >> Just FYI, this description is incorrect. SM8650's GMU doesn't do any >> sort of thermal management. > > Ok, thx for confirming this, in our tests the temperature steadily stayed > at a max trip point when setting them higher. But perhaps it's a side > effect > of other mitigations. > > Are the new trip points still ok ? they are derived from the downstream DT. I don't have expertise on the thermal side. But in my non-expert opinion, it is fine to use a similar configuration from downstream. -Akhil. > > Thanks, > Neil > >> >> -Akhil. >> >>> >>> Instead, set higher temperatures in the GPU trip points corresponding to >>> the temperatures provided by Qualcomm in the dowstream source, which >>> will >>> trigger the devfreq thermal core if the GMU cannot handle the >>> temperature >>> surge, and try our best to avoid reaching the critical temperature trip >>> point which should trigger an inevitable thermal shutdown. >>> >>> Fixes: 497624ed5506 ("arm64: dts: qcom: sm8650: Throttle the GPU when >>> overheating") >>> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org> >>> --- >>> arch/arm64/boot/dts/qcom/sm8650.dtsi | 48 +++++++++++++++++ >>> +------------------ >>> 1 file changed, 24 insertions(+), 24 deletions(-) >>> >>> diff --git a/arch/arm64/boot/dts/qcom/sm8650.dtsi b/arch/arm64/boot/ >>> dts/qcom/sm8650.dtsi >>> index >>> 95509ce2713d4fcc3dbe0c5cd5827312d5681af4..e9fcf05cb084b7979ecf0f4712fed332e9f4b07a 100644 >>> --- a/arch/arm64/boot/dts/qcom/sm8650.dtsi >>> +++ b/arch/arm64/boot/dts/qcom/sm8650.dtsi >>> @@ -6173,19 +6173,19 @@ map0 { >>> trips { >>> gpu0_alert0: trip-point0 { >>> - temperature = <85000>; >>> + temperature = <95000>; >>> hysteresis = <1000>; >>> type = "passive"; >>> }; >>> trip-point1 { >>> - temperature = <90000>; >>> + temperature = <115000>; >>> hysteresis = <1000>; >>> type = "hot"; >>> }; >>> trip-point2 { >>> - temperature = <110000>; >>> + temperature = <125000>; >>> hysteresis = <1000>; >>> type = "critical"; >>> }; >>> @@ -6206,19 +6206,19 @@ map0 { >>> trips { >>> gpu1_alert0: trip-point0 { >>> - temperature = <85000>; >>> + temperature = <95000>; >>> hysteresis = <1000>; >>> type = "passive"; >>> }; >>> trip-point1 { >>> - temperature = <90000>; >>> + temperature = <115000>; >>> hysteresis = <1000>; >>> type = "hot"; >>> }; >>> trip-point2 { >>> - temperature = <110000>; >>> + temperature = <125000>; >>> hysteresis = <1000>; >>> type = "critical"; >>> }; >>> @@ -6239,19 +6239,19 @@ map0 { >>> trips { >>> gpu2_alert0: trip-point0 { >>> - temperature = <85000>; >>> + temperature = <95000>; >>> hysteresis = <1000>; >>> type = "passive"; >>> }; >>> trip-point1 { >>> - temperature = <90000>; >>> + temperature = <115000>; >>> hysteresis = <1000>; >>> type = "hot"; >>> }; >>> trip-point2 { >>> - temperature = <110000>; >>> + temperature = <125000>; >>> hysteresis = <1000>; >>> type = "critical"; >>> }; >>> @@ -6272,19 +6272,19 @@ map0 { >>> trips { >>> gpu3_alert0: trip-point0 { >>> - temperature = <85000>; >>> + temperature = <95000>; >>> hysteresis = <1000>; >>> type = "passive"; >>> }; >>> trip-point1 { >>> - temperature = <90000>; >>> + temperature = <115000>; >>> hysteresis = <1000>; >>> type = "hot"; >>> }; >>> trip-point2 { >>> - temperature = <110000>; >>> + temperature = <125000>; >>> hysteresis = <1000>; >>> type = "critical"; >>> }; >>> @@ -6305,19 +6305,19 @@ map0 { >>> trips { >>> gpu4_alert0: trip-point0 { >>> - temperature = <85000>; >>> + temperature = <95000>; >>> hysteresis = <1000>; >>> type = "passive"; >>> }; >>> trip-point1 { >>> - temperature = <90000>; >>> + temperature = <115000>; >>> hysteresis = <1000>; >>> type = "hot"; >>> }; >>> trip-point2 { >>> - temperature = <110000>; >>> + temperature = <125000>; >>> hysteresis = <1000>; >>> type = "critical"; >>> }; >>> @@ -6338,19 +6338,19 @@ map0 { >>> trips { >>> gpu5_alert0: trip-point0 { >>> - temperature = <85000>; >>> + temperature = <95000>; >>> hysteresis = <1000>; >>> type = "passive"; >>> }; >>> trip-point1 { >>> - temperature = <90000>; >>> + temperature = <115000>; >>> hysteresis = <1000>; >>> type = "hot"; >>> }; >>> trip-point2 { >>> - temperature = <110000>; >>> + temperature = <125000>; >>> hysteresis = <1000>; >>> type = "critical"; >>> }; >>> @@ -6371,19 +6371,19 @@ map0 { >>> trips { >>> gpu6_alert0: trip-point0 { >>> - temperature = <85000>; >>> + temperature = <95000>; >>> hysteresis = <1000>; >>> type = "passive"; >>> }; >>> trip-point1 { >>> - temperature = <90000>; >>> + temperature = <115000>; >>> hysteresis = <1000>; >>> type = "hot"; >>> }; >>> trip-point2 { >>> - temperature = <110000>; >>> + temperature = <125000>; >>> hysteresis = <1000>; >>> type = "critical"; >>> }; >>> @@ -6404,19 +6404,19 @@ map0 { >>> trips { >>> gpu7_alert0: trip-point0 { >>> - temperature = <85000>; >>> + temperature = <95000>; >>> hysteresis = <1000>; >>> type = "passive"; >>> }; >>> trip-point1 { >>> - temperature = <90000>; >>> + temperature = <115000>; >>> hysteresis = <1000>; >>> type = "hot"; >>> }; >>> trip-point2 { >>> - temperature = <110000>; >>> + temperature = <125000>; >>> hysteresis = <1000>; >>> type = "critical"; >>> }; >>> >> >
On 13.01.2025 11:28 AM, Akhil P Oommen wrote: > On 1/10/2025 4:06 PM, Neil Armstrong wrote: >> On the SM8650, the dynamic clock and voltage scaling (DCVS) for the GPU >> is done in an hardware controlled loop by the GPU Management Unit (GMU). >> >> Since the GMU does a better job at maintaining the GPUs temperature in an >> acceptable range by taking in account more parameters like the die >> characteristics or other internal sensors, it makes no sense to try >> and reproduce a similar set of constraints with the Linux devfreq thermal >> core. > > Just FYI, this description is incorrect. SM8650's GMU doesn't do any > sort of thermal management. What's this for then? Just reacting to thermal pressure? https://git.codelinaro.org/clo/le/platform/vendor/qcom/opensource/graphics-kernel/-/commit/e4387d101d14965c8f2c67e10a6a9499c1a88af4 Konrad
On 1/17/2025 2:50 AM, Konrad Dybcio wrote: > On 13.01.2025 11:28 AM, Akhil P Oommen wrote: >> On 1/10/2025 4:06 PM, Neil Armstrong wrote: >>> On the SM8650, the dynamic clock and voltage scaling (DCVS) for the GPU >>> is done in an hardware controlled loop by the GPU Management Unit (GMU). >>> >>> Since the GMU does a better job at maintaining the GPUs temperature in an >>> acceptable range by taking in account more parameters like the die >>> characteristics or other internal sensors, it makes no sense to try >>> and reproduce a similar set of constraints with the Linux devfreq thermal >>> core. >> >> Just FYI, this description is incorrect. SM8650's GMU doesn't do any >> sort of thermal management. > > What's this for then? Just reacting to thermal pressure? > > https://git.codelinaro.org/clo/le/platform/vendor/qcom/opensource/graphics-kernel/-/commit/e4387d101d14965c8f2c67e10a6a9499c1a88af4 > I don't think those TSENSE configs matters on SM8650 in production. -Akhil. > Konrad
diff --git a/arch/arm64/boot/dts/qcom/sm8650.dtsi b/arch/arm64/boot/dts/qcom/sm8650.dtsi index 95509ce2713d4fcc3dbe0c5cd5827312d5681af4..e9fcf05cb084b7979ecf0f4712fed332e9f4b07a 100644 --- a/arch/arm64/boot/dts/qcom/sm8650.dtsi +++ b/arch/arm64/boot/dts/qcom/sm8650.dtsi @@ -6173,19 +6173,19 @@ map0 { trips { gpu0_alert0: trip-point0 { - temperature = <85000>; + temperature = <95000>; hysteresis = <1000>; type = "passive"; }; trip-point1 { - temperature = <90000>; + temperature = <115000>; hysteresis = <1000>; type = "hot"; }; trip-point2 { - temperature = <110000>; + temperature = <125000>; hysteresis = <1000>; type = "critical"; }; @@ -6206,19 +6206,19 @@ map0 { trips { gpu1_alert0: trip-point0 { - temperature = <85000>; + temperature = <95000>; hysteresis = <1000>; type = "passive"; }; trip-point1 { - temperature = <90000>; + temperature = <115000>; hysteresis = <1000>; type = "hot"; }; trip-point2 { - temperature = <110000>; + temperature = <125000>; hysteresis = <1000>; type = "critical"; }; @@ -6239,19 +6239,19 @@ map0 { trips { gpu2_alert0: trip-point0 { - temperature = <85000>; + temperature = <95000>; hysteresis = <1000>; type = "passive"; }; trip-point1 { - temperature = <90000>; + temperature = <115000>; hysteresis = <1000>; type = "hot"; }; trip-point2 { - temperature = <110000>; + temperature = <125000>; hysteresis = <1000>; type = "critical"; }; @@ -6272,19 +6272,19 @@ map0 { trips { gpu3_alert0: trip-point0 { - temperature = <85000>; + temperature = <95000>; hysteresis = <1000>; type = "passive"; }; trip-point1 { - temperature = <90000>; + temperature = <115000>; hysteresis = <1000>; type = "hot"; }; trip-point2 { - temperature = <110000>; + temperature = <125000>; hysteresis = <1000>; type = "critical"; }; @@ -6305,19 +6305,19 @@ map0 { trips { gpu4_alert0: trip-point0 { - temperature = <85000>; + temperature = <95000>; hysteresis = <1000>; type = "passive"; }; trip-point1 { - temperature = <90000>; + temperature = <115000>; hysteresis = <1000>; type = "hot"; }; trip-point2 { - temperature = <110000>; + temperature = <125000>; hysteresis = <1000>; type = "critical"; }; @@ -6338,19 +6338,19 @@ map0 { trips { gpu5_alert0: trip-point0 { - temperature = <85000>; + temperature = <95000>; hysteresis = <1000>; type = "passive"; }; trip-point1 { - temperature = <90000>; + temperature = <115000>; hysteresis = <1000>; type = "hot"; }; trip-point2 { - temperature = <110000>; + temperature = <125000>; hysteresis = <1000>; type = "critical"; }; @@ -6371,19 +6371,19 @@ map0 { trips { gpu6_alert0: trip-point0 { - temperature = <85000>; + temperature = <95000>; hysteresis = <1000>; type = "passive"; }; trip-point1 { - temperature = <90000>; + temperature = <115000>; hysteresis = <1000>; type = "hot"; }; trip-point2 { - temperature = <110000>; + temperature = <125000>; hysteresis = <1000>; type = "critical"; }; @@ -6404,19 +6404,19 @@ map0 { trips { gpu7_alert0: trip-point0 { - temperature = <85000>; + temperature = <95000>; hysteresis = <1000>; type = "passive"; }; trip-point1 { - temperature = <90000>; + temperature = <115000>; hysteresis = <1000>; type = "hot"; }; trip-point2 { - temperature = <110000>; + temperature = <125000>; hysteresis = <1000>; type = "critical"; };
On the SM8650, the dynamic clock and voltage scaling (DCVS) for the GPU is done in an hardware controlled loop by the GPU Management Unit (GMU). Since the GMU does a better job at maintaining the GPUs temperature in an acceptable range by taking in account more parameters like the die characteristics or other internal sensors, it makes no sense to try and reproduce a similar set of constraints with the Linux devfreq thermal core. Instead, set higher temperatures in the GPU trip points corresponding to the temperatures provided by Qualcomm in the dowstream source, which will trigger the devfreq thermal core if the GMU cannot handle the temperature surge, and try our best to avoid reaching the critical temperature trip point which should trigger an inevitable thermal shutdown. Fixes: 497624ed5506 ("arm64: dts: qcom: sm8650: Throttle the GPU when overheating") Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org> --- arch/arm64/boot/dts/qcom/sm8650.dtsi | 48 ++++++++++++++++++------------------ 1 file changed, 24 insertions(+), 24 deletions(-)