Messages in this thread | | | Date | Wed, 16 Feb 2022 14:13:58 -0800 | From | Matthias Kaehlcke <> | Subject | Re: [PATCH 1/2] thermal: cooling: Check Energy Model type in cpufreq_cooling and devfreq_cooling |
| |
On Wed, Feb 16, 2022 at 09:33:50AM -0800, Doug Anderson wrote: > Hi, > > On Wed, Feb 16, 2022 at 7:35 AM Lukasz Luba <lukasz.luba@arm.com> wrote: > > > > Hi Matthias, > > > > On 2/9/22 10:17 PM, Matthias Kaehlcke wrote: > > > On Wed, Feb 09, 2022 at 11:16:36AM +0000, Lukasz Luba wrote: > > >> > > >> > > >> On 2/8/22 5:25 PM, Matthias Kaehlcke wrote: > > >>> On Tue, Feb 08, 2022 at 09:32:28AM +0000, Lukasz Luba wrote: > > >>>> > > >>>> > > > > [snip] > > > > >>>> Could you point me to those devices please? > > >>> > > >>> arch/arm64/boot/dts/qcom/sc7180-trogdor-* > > >>> > > >>> Though as per above they shouldn't be impacted by your change, since the > > >>> CPUs always pretend to use milli-Watts. > > >>> > > >>> [skipped some questions/answers since sc7180 isn't actually impacted by > > >>> the change] > > >> > > >> Thank you Matthias. I will investigate your setup to get better > > >> understanding. > > > > > > Thanks! > > > > > > > I've checked those DT files and related code. > > As you already said, this patch is safe for them. > > So we can apply it IMO. > > > > > > -------------Off-topic------------------ > > Not in $subject comments: > > > > AFAICS based on two files which define thermal zones: > > sc7180-trogdor-homestar.dtsi > > sc7180-trogdor-coachz.dtsi > > > > only the 'big' cores are used as cooling devices in the > > 'skin_temp_thermal' - the CPU6 and CPU7. > > > > I assume you don't want to model at all the power usage > > from the Little cluster (which is quite big: 6 CPUs), do you? > > I can see that the Little CPUs have small dyn-power-coeff > > ~30% of the big and lower max freq, but still might be worth > > to add them to IPA. You might give them more 'weight', to > > make sure they receive more power during power split.
In experiments we saw that including the little cores as cooling devices for 'skin_temp_thermal' didn't have a significant impact on thermals, so we left them out.
> > You also don't have GPU cooling device in that thermal zone. > > Based on my experience if your GPU is a power hungry one, > > e.g. 2-4Watts, you might get better results when you model > > this 'hot' device (which impacts your temp sensor reported value). > > I think the two boards you point at (homestar and coachz) are just the > two that override the default defined in the SoC dtsi file. If you > look in sc7180.dtsi you'll see 'gpuss1-thermal' which has a cooling > map. You can also see the cooling maps for the littles.
Yep, plus thermal zones with cooling maps for the big cores.
> I guess we don't have a `dynamic-power-coefficient` for the GPU, > though? Seems like we should, but I haven't dug through all the code > here...
To my knowledge the SC7x80 GPU doesn't register an energy model, which is one of the reasons the GPU wasn't included as cooling device for 'skin_temp_thermal'.
| |