For Marvell: https://www.google.com/url?sa=t&source=web&rct=j&url=https://wiki.kobol.io/helios4/files/som/brochure_a38x_microsom_2017-09-05.pdf Armada38x maximum die temperature 115 degrees Celcius. They really get hotter then 100. But for mt7622 I cannot find this value Get BlueMail for Android On Jun 23, 2021, 10:08 PM, at 10:08 PM, Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> wrote: >On 23/06/2021 20:43, Eric Woudstra wrote: >> >> I choose "hot" before, because 87 degrees seems ok to start frequency >> throttling. But, yes, it should be passive. >> >> 87 is still quite low if I compare this temperature with the >> wrt3200acm Marvell dual core arm soc. They even went above 100 >> degrees so I feel for an arm processor inside a router box it is fine >> to use 87 degrees But maybe someone at Mediatek can give some more >> details about operating temperatures. > >Sometimes, the SoC vendor puts a high temperature in the DT just to >export the thermal zone and deal with it from userspace. So putting the >high temp allow the userspace (usually a thermal engine - Android >stuff) >to deal with the mitigation without a kernel interaction. > >Having more than 100°C could be this kind of setup. Only the operating >temperature from the hardware documentation will tell the safe >temperature for the silicon. > >IMO, 77°C is a good compromise until getting the documented temp. 87°C >sounds to me a bit too hot. > >> It may be possible to leave the active map in the device tree as some >> users of the bananapi might choose to install a fan as it is one of >> the options. > >The active trip only makes sense if the cooling device is a fan (or any >active device), so the mapping points to a fan node, like: > >https://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux.git/tree/arch/arm64/boot/dts/rockchip/rk3399-khadas-edge.dtsi#n192 > >If there is no such [pwm] fan output on the board, no active trip point >should be added. > >> Get BlueMail for Android >> >> On Jun 23, 2021, 5:58 PM, at 5:58 PM, Daniel Lezcano >> <daniel.lezcano@xxxxxxxxxx> wrote: >>> On 23/06/2021 17:35, Eric Woudstra wrote: >>>> It is only useful to set 1 map with the regulated temperature for >>>> cpu frequency throttling. Same as in the kernel document >>>> example. >>>> >>>> >>>> It has no use to set frequency scaling on 2 different >>>> temperature trip points, as the lowest one makes sure the higher >>>> one(s) are never reached. >>> >>> I looked more closely the DT and there is a misunderstanding of >>> the thermal framework in the definition. >>> >>> There is one trip point with the passive type and the cpu cooling >>> device, followed by a second trip point with the active type *but* >>> the same cpu cooling device. That is wrong. >>> >>> And finally, there is the hot trip point as a third mapping and >>> the same cooling device. >>> >>> The hot trip point is only there to notify userspace and let it >>> take an immediate action to prevent an emergency shutdown when >>> reaching the critical temperature. >>> >>>> It can be applied only at 1 trip point. Multiple trip points is >>>> only usefully for fan control to make sure the fan is not too >>>> noisy when it is not necessary to be noisy. >>>> >>>> >>>> The CPU will almost come to a dead stop when it starts to pass >>>> the lowest thermal map with frequency throttling. >>>> >>>> This is why it is a bug and needs a fix, not only adjustment. >>> >>> Yes, you are right. It should be something like (verbatim copy): >>> >>> diff --git a/arch/arm64/boot/dts/mediatek/mt7622.dtsi >>> b/arch/arm64/boot/dts/mediatek/mt7622.dtsi index >>> 890a942ec608..88c81d24f4ff 100644 --- >>> a/arch/arm64/boot/dts/mediatek/mt7622.dtsi +++ >>> b/arch/arm64/boot/dts/mediatek/mt7622.dtsi @@ -136,24 +136,18 @@ >>> secmon_reserved: secmon@43000000 { >>> >>> thermal-zones { cpu_thermal: cpu-thermal { - >>> polling-delay-passive = <1000>; + polling-delay-passive = <250>; >>> polling-delay = <1000>; >>> >>> thermal-sensors = <&thermal 0>; >>> >>> trips { cpu_passive: cpu-passive { - temperature = <47000>; + >>> temperature = <77000>; hysteresis = <2000>; type = "passive"; }; >>> >>> - cpu_active: cpu-active { - temperature = <67000>; - >>> hysteresis = <2000>; - type = "active"; - }; - cpu_hot: >>> cpu-hot { temperature = <87000>; hysteresis = <2000>; @@ -173,18 >>> +167,6 @@ map0 { cooling-device = <&cpu0 THERMAL_NO_LIMIT >>> THERMAL_NO_LIMIT>, <&cpu1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>; }; - >>> - map1 { - trip = <&cpu_active>; - cooling-device = >>> <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>, - <&cpu1 >>> THERMAL_NO_LIMIT THERMAL_NO_LIMIT>; - }; - - map2 { - >>> trip = <&cpu_hot>; - cooling-device = <&cpu0 THERMAL_NO_LIMIT >>> THERMAL_NO_LIMIT>, - <&cpu1 THERMAL_NO_LIMIT >>> THERMAL_NO_LIMIT>; - }; }; }; }; >>> >>> >>> -- <http://www.linaro.org/> Linaro.org │ Open source software for >>> ARM SoCs >>> >>> Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | >>> <http://twitter.com/#!/linaroorg> Twitter | >>> <http://www.linaro.org/linaro-blog/> Blog >> > > >-- ><http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs > >Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | ><http://twitter.com/#!/linaroorg> Twitter | ><http://www.linaro.org/linaro-blog/> Blog
