Re: [PATCH v3 0/7] Add support for Allwinner H6 DVFS

Clément Péron
2020-04-20T12:49:34Z

Hi Maxime

On Mon, 20 Apr 2020 at 14:47, Maxime Ripard <maxime@cerno.tech> wrote:
>
> On Mon, Apr 20, 2020 at 02:36:32PM +0200, Clément Péron wrote:
> > Hi Ondrej, Maxime,
> >
> > On Mon, 20 Apr 2020 at 12:39, Ondřej Jirman <megous@megous.com> wrote:
> > >
> > > Hi Maxime,
> > >
> > > On Mon, Apr 20, 2020 at 10:45:47AM +0200, Maxime Ripard wrote:
> > > > Hi,
> > > >
> > > > On Sun, Apr 19, 2020 at 03:50:04PM +0200, Clément Péron wrote:
> > > > > Now that required drivers are merged we can contibute on DVFS
> > > > > support for Allwinner H6.
> > > > >
> > > > > This serie is based on Yangtao Li serie[0] and Ondřej Jirman work[1].
> > > > >
> > > > > Most of the OPP tables are taken from original vendor kernel[2].
> > > > > Plus there are new CPU frequencies at 1.6GHz, 1.7GHz and 1.8GHz.
> > > > >
> > > > > I wrote a simple script to randomly set a frequency during
> > > > > a random time[3]. This script is quite stressfull and set some high
> > > > > frequency without checking temperature. This can result on behavior
> > > > > that whould not occurs with the real cpufreq framework.
> > > > > As Maxime point out I also tested with cpufreq-ljt-stress-test
> > > > > (found here https://github.com/ssvb/cpuburn-arm).
> > > > > This script doesn't trigger any issue.
> > > > > I also test that that offlining CPU0 and doing DVFS on other CPUs
> > > > > works. As CPU regulator is only set for CPU0.
> > > > >
> > > > > The GPU devfreq was drop as the regulator is still not properly
> > > > > drive by panfrost driver[4].
> > > > > I will re-introduce it later.
> > > > >
> > > > > Ondřej Jirman has an Orange Pi 3, Jernej has a PineH64 and a Tanix
> > > > > TX6 boards and I have a Beelink GS1 board so I have enable these
> > > > > boards. But CPU Devfreq is really touchy has it depends on:
> > > > > board design, SoC speed_grade and environement which can affect
> > > > > thermal cooling and have different behavior for different user.
> > > > >
> > > > > If people can test this serie and give feedback, I will try to
> > > > > introduce this in LibreElec tree, so LE community can test it.
> > > >
> > > > Applied all of them, thanks!
> > >
> > > Please also apply "[PATCH v2 1/7] arm64: dts: allwinner: h6: Add
> > > clock to CPU cores" from the v2 series, otherwise cpufreq will
> > > not work.
> > >
> > > I can also send a missing patch adding the trip points, and cpu
> > > as a cooling device, that I linked in my other reply to this patch
> > > series afterwards, if Clément wants.
> >
> > Indeed I have sent using the following cmd : "git send-email --to=XXXX HEAD~7"
> > from the previous version.
> >
> > I should had do Instead: "git send-email --to=XXXX next/master "
> >
> > Sorry for that :(
>
> I haven't pushed anything yet, can you resend the proper branch?

Yes, I will,

Thanks!
>
> Thanks!
> Maxime