| Message ID | a17e0df64c5b976b47f19c5a29c02759cd9e5b8c.1723427375.git.dsimic@manjaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64: dts: allwinner: Add GPU thermal trips to the SoC dtsi for A64 | expand |
在 2024-08-12星期一的 04:00 +0200，Dragan Simic写道： > Add thermal trips for the two GPU thermal sensors found in the > Allwinner A64. > There's only one GPU OPP defined since the commit 1428f0c19f9c > ("arm64: dts: > allwinner: a64: Run GPU at 432 MHz"), so defining only the critical > thermal > trips makes sense for the A64's two GPU thermal zones. > > Having these critical thermal trips defined ensures that no hot spots > develop > inside the SoC die that exceed the maximum junction temperature. > That might > have been possible before, although quite unlikely, because the CPU > and GPU > portions of the SoC are packed closely inside the SoC, so the > overheating GPU > would inevitably result in the heat soaking into the CPU portion of > the SoC, > causing the CPU thermal sensor to return high readings and trigger > the CPU > critical thermal trips. However, it's better not to rely on the heat > soak > and have the critical GPU thermal trips properly defined instead. > > While there, remove a few spotted comments that are rather redundant, > because > it's pretty much obvious what units are used in those places. This should be another individual patch, I think. > > Signed-off-by: Dragan Simic <dsimic@manjaro.org> > --- > arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 22 ++++++++++++++--- > -- > 1 file changed, 16 insertions(+), 6 deletions(-) > > diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi > b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi > index e868ca5ae753..bc5d3a2e6c98 100644 > --- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi > +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi > @@ -212,7 +212,6 @@ timer { > > thermal-zones { > cpu_thermal: cpu0-thermal { > - /* milliseconds */ The unit of a 0 isn't not so obvious I think, so I suggest to keep this. > polling-delay-passive = <0>; > polling-delay = <0>; > thermal-sensors = <&ths 0>; > @@ -236,40 +235,51 @@ map1 { > > trips { > cpu_alert0: cpu-alert0 { > - /* milliCelsius */ > temperature = <75000>; > hysteresis = <2000>; > type = "passive"; > }; > > cpu_alert1: cpu-alert1 { > - /* milliCelsius */ > temperature = <90000>; > hysteresis = <2000>; > type = "hot"; > }; > > cpu_crit: cpu-crit { > - /* milliCelsius */ > temperature = <110000>; > hysteresis = <2000>; > type = "critical"; > }; > }; > }; > > gpu0_thermal: gpu0-thermal { > - /* milliseconds */ > polling-delay-passive = <0>; > polling-delay = <0>; > thermal-sensors = <&ths 1>; > + > + trips { > + gpu0_crit: gpu0-crit { > + temperature = <110000>; > + hysteresis = <2000>; > + type = "critical"; > + }; > + }; > }; > > gpu1_thermal: gpu1-thermal { > - /* milliseconds */ > polling-delay-passive = <0>; > polling-delay = <0>; > thermal-sensors = <&ths 2>; > + > + trips { > + gpu1_crit: gpu1-crit { > + temperature = <110000>; > + hysteresis = <2000>; > + type = "critical"; > + }; > + }; > }; > }; >
Hello Icenowy, On 2024-08-12 04:40, Icenowy Zheng wrote: > 在 2024-08-12星期一的 04:00 +0200，Dragan Simic写道： >> Add thermal trips for the two GPU thermal sensors found in the >> Allwinner A64. >> There's only one GPU OPP defined since the commit 1428f0c19f9c >> ("arm64: dts: >> allwinner: a64: Run GPU at 432 MHz"), so defining only the critical >> thermal >> trips makes sense for the A64's two GPU thermal zones. >> >> Having these critical thermal trips defined ensures that no hot spots >> develop >> inside the SoC die that exceed the maximum junction temperature. >> That might >> have been possible before, although quite unlikely, because the CPU >> and GPU >> portions of the SoC are packed closely inside the SoC, so the >> overheating GPU >> would inevitably result in the heat soaking into the CPU portion of >> the SoC, >> causing the CPU thermal sensor to return high readings and trigger >> the CPU >> critical thermal trips. However, it's better not to rely on the heat >> soak >> and have the critical GPU thermal trips properly defined instead. >> >> While there, remove a few spotted comments that are rather redundant, >> because >> it's pretty much obvious what units are used in those places. > > This should be another individual patch, I think. Perhaps, which I already thought about, but it might also be best to simply drop the removal of those redundant comments entirely. Let's also see what will other people say. >> Signed-off-by: Dragan Simic <dsimic@manjaro.org> >> --- >> arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 22 ++++++++++++++--- >> -- >> 1 file changed, 16 insertions(+), 6 deletions(-) >> >> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >> b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >> index e868ca5ae753..bc5d3a2e6c98 100644 >> --- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >> @@ -212,7 +212,6 @@ timer { >> >> thermal-zones { >> cpu_thermal: cpu0-thermal { >> - /* milliseconds */ > > The unit of a 0 isn't not so obvious I think, so I suggest to keep > this. Quite frankly, I think it should be obvious to anyone tackling the thermal zones and trips. >> polling-delay-passive = <0>; >> polling-delay = <0>; >> thermal-sensors = <&ths 0>; >> @@ -236,40 +235,51 @@ map1 { >> >> trips { >> cpu_alert0: cpu-alert0 { >> - /* milliCelsius */ >> temperature = <75000>; >> hysteresis = <2000>; >> type = "passive"; >> }; >> >> cpu_alert1: cpu-alert1 { >> - /* milliCelsius */ >> temperature = <90000>; >> hysteresis = <2000>; >> type = "hot"; >> }; >> >> cpu_crit: cpu-crit { >> - /* milliCelsius */ >> temperature = <110000>; >> hysteresis = <2000>; >> type = "critical"; >> }; >> }; >> }; >> >> gpu0_thermal: gpu0-thermal { >> - /* milliseconds */ >> polling-delay-passive = <0>; >> polling-delay = <0>; >> thermal-sensors = <&ths 1>; >> + >> + trips { >> + gpu0_crit: gpu0-crit { >> + temperature = <110000>; >> + hysteresis = <2000>; >> + type = "critical"; >> + }; >> + }; >> }; >> >> gpu1_thermal: gpu1-thermal { >> - /* milliseconds */ >> polling-delay-passive = <0>; >> polling-delay = <0>; >> thermal-sensors = <&ths 2>; >> + >> + trips { >> + gpu1_crit: gpu1-crit { >> + temperature = <110000>; >> + hysteresis = <2000>; >> + type = "critical"; >> + }; >> + }; >> }; >> }; >>
On 12/08/2024 04:46, Dragan Simic wrote: > Hello Icenowy, > > On 2024-08-12 04:40, Icenowy Zheng wrote: >> 在 2024-08-12星期一的 04:00 +0200，Dragan Simic写道： >>> Add thermal trips for the two GPU thermal sensors found in the >>> Allwinner A64. >>> There's only one GPU OPP defined since the commit 1428f0c19f9c >>> ("arm64: dts: >>> allwinner: a64: Run GPU at 432 MHz"), so defining only the critical >>> thermal >>> trips makes sense for the A64's two GPU thermal zones. >>> >>> Having these critical thermal trips defined ensures that no hot spots >>> develop >>> inside the SoC die that exceed the maximum junction temperature. >>> That might >>> have been possible before, although quite unlikely, because the CPU >>> and GPU >>> portions of the SoC are packed closely inside the SoC, so the >>> overheating GPU >>> would inevitably result in the heat soaking into the CPU portion of >>> the SoC, >>> causing the CPU thermal sensor to return high readings and trigger >>> the CPU >>> critical thermal trips. However, it's better not to rely on the heat >>> soak >>> and have the critical GPU thermal trips properly defined instead. >>> >>> While there, remove a few spotted comments that are rather redundant, >>> because >>> it's pretty much obvious what units are used in those places. >> >> This should be another individual patch, I think. > > Perhaps, which I already thought about, but it might also be best > to simply drop the removal of those redundant comments entirely. > Let's also see what will other people say. > >>> Signed-off-by: Dragan Simic <dsimic@manjaro.org> >>> --- >>> arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 22 ++++++++++++++--- >>> -- >>> 1 file changed, 16 insertions(+), 6 deletions(-) >>> >>> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >>> b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >>> index e868ca5ae753..bc5d3a2e6c98 100644 >>> --- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >>> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >>> @@ -212,7 +212,6 @@ timer { >>> >>> thermal-zones { >>> cpu_thermal: cpu0-thermal { >>> - /* milliseconds */ >> >> The unit of a 0 isn't not so obvious I think, so I suggest to keep >> this. > > Quite frankly, I think it should be obvious to anyone tackling > the thermal zones and trips. You can remove also polling-delay-passive and polling-passive when they are equal to zero. If they are absent they will be set to zero by default. That said, I take the opportunity to spot some inconsistency in this DT not related to this change. 1. There is a passive trip point and one cooling device mapped to it. With a polling-delay-passive=0, the mitigation will fail 2. There is a second mapping for the hot trip point. That does not make sense, it is not possible because there is no mitigation for 'hot' and 'critical' trip points.
Hello Daniel, On 2024-08-19 17:42, Daniel Lezcano wrote: > On 12/08/2024 04:46, Dragan Simic wrote: >> On 2024-08-12 04:40, Icenowy Zheng wrote: >>> 在 2024-08-12星期一的 04:00 +0200，Dragan Simic写道： >>>> Add thermal trips for the two GPU thermal sensors found in the >>>> Allwinner A64. >>>> There's only one GPU OPP defined since the commit 1428f0c19f9c >>>> ("arm64: dts: >>>> allwinner: a64: Run GPU at 432 MHz"), so defining only the critical >>>> thermal >>>> trips makes sense for the A64's two GPU thermal zones. >>>> >>>> Having these critical thermal trips defined ensures that no hot >>>> spots >>>> develop >>>> inside the SoC die that exceed the maximum junction temperature. >>>> That might >>>> have been possible before, although quite unlikely, because the CPU >>>> and GPU >>>> portions of the SoC are packed closely inside the SoC, so the >>>> overheating GPU >>>> would inevitably result in the heat soaking into the CPU portion of >>>> the SoC, >>>> causing the CPU thermal sensor to return high readings and trigger >>>> the CPU >>>> critical thermal trips. However, it's better not to rely on the >>>> heat >>>> soak >>>> and have the critical GPU thermal trips properly defined instead. >>>> >>>> While there, remove a few spotted comments that are rather >>>> redundant, >>>> because >>>> it's pretty much obvious what units are used in those places. >>> >>> This should be another individual patch, I think. >> >> Perhaps, which I already thought about, but it might also be best >> to simply drop the removal of those redundant comments entirely. >> Let's also see what will other people say. >> >>>> Signed-off-by: Dragan Simic <dsimic@manjaro.org> >>>> --- >>>> arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 22 >>>> ++++++++++++++--- >>>> -- 1 file changed, 16 insertions(+), 6 deletions(-) >>>> >>>> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >>>> b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >>>> index e868ca5ae753..bc5d3a2e6c98 100644 >>>> --- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >>>> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >>>> @@ -212,7 +212,6 @@ timer { >>>> >>>> thermal-zones { >>>> cpu_thermal: cpu0-thermal { >>>> - /* milliseconds */ >>> >>> The unit of a 0 isn't not so obvious I think, so I suggest to keep >>> this. >> >> Quite frankly, I think it should be obvious to anyone tackling >> the thermal zones and trips. > > You can remove also polling-delay-passive and polling-passive when > they are equal to zero. If they are absent they will be set to zero by > default. Good point, thanks! Though, I'd rather leave those "... = <0>;" removals for a small follow-up series, because those changes touch more actual code than just the comments, so it's better to keep them as separate changes for easier bisection later, if it's ever needed. Hopefully never. :) I just made a note for myself to create and submit those follow-up cleanup patches later, for all affected Allwinner and Rockchip SoC dtsi files. > That said, I take the opportunity to spot some inconsistency in this > DT not related to this change. > > 1. There is a passive trip point and one cooling device mapped to it. > With a polling-delay-passive=0, the mitigation will fail Huh, how is the CPU throttling working then? Thanks for pointing it out, I'll address this issue in the follow-up patches. > 2. There is a second mapping for the hot trip point. That does not > make sense, it is not possible because there is no mitigation for > 'hot' and 'critical' trip points. Yup, I see no special handling of tz->ops.hot, so having the hot trip point makes no sense. Thanks again for pointing it out, I'll address this issue in the follow-up patches as well. I'll send the v2 soon, as a small patch series, and I'll send a few follow-up patches later.
On Mon, Aug 12, 2024 at 10:46 AM Dragan Simic <dsimic@manjaro.org> wrote: > > Hello Icenowy, > > On 2024-08-12 04:40, Icenowy Zheng wrote: > > 在 2024-08-12星期一的 04:00 +0200，Dragan Simic写道： > >> Add thermal trips for the two GPU thermal sensors found in the > >> Allwinner A64. > >> There's only one GPU OPP defined since the commit 1428f0c19f9c > >> ("arm64: dts: > >> allwinner: a64: Run GPU at 432 MHz"), so defining only the critical > >> thermal > >> trips makes sense for the A64's two GPU thermal zones. > >> > >> Having these critical thermal trips defined ensures that no hot spots > >> develop > >> inside the SoC die that exceed the maximum junction temperature. > >> That might > >> have been possible before, although quite unlikely, because the CPU > >> and GPU > >> portions of the SoC are packed closely inside the SoC, so the > >> overheating GPU > >> would inevitably result in the heat soaking into the CPU portion of > >> the SoC, > >> causing the CPU thermal sensor to return high readings and trigger > >> the CPU > >> critical thermal trips. However, it's better not to rely on the heat > >> soak > >> and have the critical GPU thermal trips properly defined instead. > >> > >> While there, remove a few spotted comments that are rather redundant, > >> because > >> it's pretty much obvious what units are used in those places. > > > > This should be another individual patch, I think. > > Perhaps, which I already thought about, but it might also be best > to simply drop the removal of those redundant comments entirely. > Let's also see what will other people say. > > >> Signed-off-by: Dragan Simic <dsimic@manjaro.org> > >> --- > >> arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 22 ++++++++++++++--- > >> -- > >> 1 file changed, 16 insertions(+), 6 deletions(-) > >> > >> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi > >> b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi > >> index e868ca5ae753..bc5d3a2e6c98 100644 > >> --- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi > >> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi > >> @@ -212,7 +212,6 @@ timer { > >> > >> thermal-zones { > >> cpu_thermal: cpu0-thermal { > >> - /* milliseconds */ > > > > The unit of a 0 isn't not so obvious I think, so I suggest to keep > > this. > > Quite frankly, I think it should be obvious to anyone tackling > the thermal zones and trips. Sorry for the late reply. Not everyone writing or editing the DT would be fully familiar with all the bindings. As Icenowy mentioned, it's not even obvious when the existing value is zero. I would prefer we keep them. ChenYu > >> polling-delay-passive = <0>; > >> polling-delay = <0>; > >> thermal-sensors = <&ths 0>; > >> @@ -236,40 +235,51 @@ map1 { > >> > >> trips { > >> cpu_alert0: cpu-alert0 { > >> - /* milliCelsius */ > >> temperature = <75000>; > >> hysteresis = <2000>; > >> type = "passive"; > >> }; > >> > >> cpu_alert1: cpu-alert1 { > >> - /* milliCelsius */ > >> temperature = <90000>; > >> hysteresis = <2000>; > >> type = "hot"; > >> }; > >> > >> cpu_crit: cpu-crit { > >> - /* milliCelsius */ > >> temperature = <110000>; > >> hysteresis = <2000>; > >> type = "critical"; > >> }; > >> }; > >> }; > >> > >> gpu0_thermal: gpu0-thermal { > >> - /* milliseconds */ > >> polling-delay-passive = <0>; > >> polling-delay = <0>; > >> thermal-sensors = <&ths 1>; > >> + > >> + trips { > >> + gpu0_crit: gpu0-crit { > >> + temperature = <110000>; > >> + hysteresis = <2000>; > >> + type = "critical"; > >> + }; > >> + }; > >> }; > >> > >> gpu1_thermal: gpu1-thermal { > >> - /* milliseconds */ > >> polling-delay-passive = <0>; > >> polling-delay = <0>; > >> thermal-sensors = <&ths 2>; > >> + > >> + trips { > >> + gpu1_crit: gpu1-crit { > >> + temperature = <110000>; > >> + hysteresis = <2000>; > >> + type = "critical"; > >> + }; > >> + }; > >> }; > >> }; > >>
Hello Chen-Yu, On 2024-08-20 05:37, Chen-Yu Tsai wrote: > On Mon, Aug 12, 2024 at 10:46 AM Dragan Simic <dsimic@manjaro.org> > wrote: >> >> Hello Icenowy, >> >> On 2024-08-12 04:40, Icenowy Zheng wrote: >> > 在 2024-08-12星期一的 04:00 +0200，Dragan Simic写道： >> >> Add thermal trips for the two GPU thermal sensors found in the >> >> Allwinner A64. >> >> There's only one GPU OPP defined since the commit 1428f0c19f9c >> >> ("arm64: dts: >> >> allwinner: a64: Run GPU at 432 MHz"), so defining only the critical >> >> thermal >> >> trips makes sense for the A64's two GPU thermal zones. >> >> >> >> Having these critical thermal trips defined ensures that no hot spots >> >> develop >> >> inside the SoC die that exceed the maximum junction temperature. >> >> That might >> >> have been possible before, although quite unlikely, because the CPU >> >> and GPU >> >> portions of the SoC are packed closely inside the SoC, so the >> >> overheating GPU >> >> would inevitably result in the heat soaking into the CPU portion of >> >> the SoC, >> >> causing the CPU thermal sensor to return high readings and trigger >> >> the CPU >> >> critical thermal trips. However, it's better not to rely on the heat >> >> soak >> >> and have the critical GPU thermal trips properly defined instead. >> >> >> >> While there, remove a few spotted comments that are rather redundant, >> >> because >> >> it's pretty much obvious what units are used in those places. >> > >> > This should be another individual patch, I think. >> >> Perhaps, which I already thought about, but it might also be best >> to simply drop the removal of those redundant comments entirely. >> Let's also see what will other people say. >> >> >> Signed-off-by: Dragan Simic <dsimic@manjaro.org> >> >> --- >> >> arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 22 ++++++++++++++--- >> >> -- >> >> 1 file changed, 16 insertions(+), 6 deletions(-) >> >> >> >> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >> >> b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >> >> index e868ca5ae753..bc5d3a2e6c98 100644 >> >> --- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >> >> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi >> >> @@ -212,7 +212,6 @@ timer { >> >> >> >> thermal-zones { >> >> cpu_thermal: cpu0-thermal { >> >> - /* milliseconds */ >> > >> > The unit of a 0 isn't not so obvious I think, so I suggest to keep >> > this. >> >> Quite frankly, I think it should be obvious to anyone tackling >> the thermal zones and trips. > > Sorry for the late reply. No worries. > Not everyone writing or editing the DT would be fully familiar with > all the bindings. As Icenowy mentioned, it's not even obvious when > the existing value is zero. I would prefer we keep them. That's two votes for keeping the already present comments, so I'll drop their removal in the v2. >> >> polling-delay-passive = <0>; >> >> polling-delay = <0>; >> >> thermal-sensors = <&ths 0>; >> >> @@ -236,40 +235,51 @@ map1 { >> >> >> >> trips { >> >> cpu_alert0: cpu-alert0 { >> >> - /* milliCelsius */ >> >> temperature = <75000>; >> >> hysteresis = <2000>; >> >> type = "passive"; >> >> }; >> >> >> >> cpu_alert1: cpu-alert1 { >> >> - /* milliCelsius */ >> >> temperature = <90000>; >> >> hysteresis = <2000>; >> >> type = "hot"; >> >> }; >> >> >> >> cpu_crit: cpu-crit { >> >> - /* milliCelsius */ >> >> temperature = <110000>; >> >> hysteresis = <2000>; >> >> type = "critical"; >> >> }; >> >> }; >> >> }; >> >> >> >> gpu0_thermal: gpu0-thermal { >> >> - /* milliseconds */ >> >> polling-delay-passive = <0>; >> >> polling-delay = <0>; >> >> thermal-sensors = <&ths 1>; >> >> + >> >> + trips { >> >> + gpu0_crit: gpu0-crit { >> >> + temperature = <110000>; >> >> + hysteresis = <2000>; >> >> + type = "critical"; >> >> + }; >> >> + }; >> >> }; >> >> >> >> gpu1_thermal: gpu1-thermal { >> >> - /* milliseconds */ >> >> polling-delay-passive = <0>; >> >> polling-delay = <0>; >> >> thermal-sensors = <&ths 2>; >> >> + >> >> + trips { >> >> + gpu1_crit: gpu1-crit { >> >> + temperature = <110000>; >> >> + hysteresis = <2000>; >> >> + type = "critical"; >> >> + }; >> >> + }; >> >> }; >> >> }; >> >>
diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi index e868ca5ae753..bc5d3a2e6c98 100644 --- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi @@ -212,7 +212,6 @@ timer { thermal-zones { cpu_thermal: cpu0-thermal { - /* milliseconds */ polling-delay-passive = <0>; polling-delay = <0>; thermal-sensors = <&ths 0>; @@ -236,40 +235,51 @@ map1 { trips { cpu_alert0: cpu-alert0 { - /* milliCelsius */ temperature = <75000>; hysteresis = <2000>; type = "passive"; }; cpu_alert1: cpu-alert1 { - /* milliCelsius */ temperature = <90000>; hysteresis = <2000>; type = "hot"; }; cpu_crit: cpu-crit { - /* milliCelsius */ temperature = <110000>; hysteresis = <2000>; type = "critical"; }; }; }; gpu0_thermal: gpu0-thermal { - /* milliseconds */ polling-delay-passive = <0>; polling-delay = <0>; thermal-sensors = <&ths 1>; + + trips { + gpu0_crit: gpu0-crit { + temperature = <110000>; + hysteresis = <2000>; + type = "critical"; + }; + }; }; gpu1_thermal: gpu1-thermal { - /* milliseconds */ polling-delay-passive = <0>; polling-delay = <0>; thermal-sensors = <&ths 2>; + + trips { + gpu1_crit: gpu1-crit { + temperature = <110000>; + hysteresis = <2000>; + type = "critical"; + }; + }; }; };
Add thermal trips for the two GPU thermal sensors found in the Allwinner A64. There's only one GPU OPP defined since the commit 1428f0c19f9c ("arm64: dts: allwinner: a64: Run GPU at 432 MHz"), so defining only the critical thermal trips makes sense for the A64's two GPU thermal zones. Having these critical thermal trips defined ensures that no hot spots develop inside the SoC die that exceed the maximum junction temperature. That might have been possible before, although quite unlikely, because the CPU and GPU portions of the SoC are packed closely inside the SoC, so the overheating GPU would inevitably result in the heat soaking into the CPU portion of the SoC, causing the CPU thermal sensor to return high readings and trigger the CPU critical thermal trips. However, it's better not to rely on the heat soak and have the critical GPU thermal trips properly defined instead. While there, remove a few spotted comments that are rather redundant, because it's pretty much obvious what units are used in those places. Signed-off-by: Dragan Simic <dsimic@manjaro.org> --- arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 22 ++++++++++++++----- 1 file changed, 16 insertions(+), 6 deletions(-)