Re: [PATCH v2 13/14] [DO NOT MERGE] arm64: dts: allwinner: h6: Add GPU OPP table

[ClÃment PÃron]

Hi Maxime,

On Sat, 4 Jul 2020 at 14:13, Maxime Ripard <maxime@xxxxxxxxxx> wrote:
>
> Hi,
>
> On Sat, Jul 04, 2020 at 12:25:34PM +0200, ClÃment PÃron wrote:
> > Add an Operating Performance Points table for the GPU to
> > enable Dynamic Voltage & Frequency Scaling on the H6.
> >
> > The voltage range is set with minival voltage set to the target
> > and the maximal voltage set to 1.2V. This allow DVFS framework to
> > work properly on board with fixed regulator.
> >
> > Signed-off-by: ClÃment PÃron <peron.clem@xxxxxxxxx>
>
> That patch seems reasonable, why shouldn't we merge it?

I didn't test it a lot and last time I did, some frequencies looked unstable.
https://lore.kernel.org/patchwork/cover/1239739/

This series adds regulator support to Panfrost devfreq, I will send a
new one if DVFS on the H6 GPU is stable.

I got this running glmark2 last time
# glmark2-es2-drm
=======================================================
    glmark2 2017.07
=======================================================
    OpenGL Information
    GL_VENDOR:     Panfrost
    GL_RENDERER:   Mali T720 (Panfrost)
    GL_VERSION:    OpenGL ES 2.0 Mesa 20.0.5
=======================================================

[   93.550063] panfrost 1800000.gpu: GPU Fault 0x00000088 (UNKNOWN) at
0x0000000080117100
[   94.045401] panfrost 1800000.gpu: gpu sched timeout, js=0,
config=0x3700, status=0x8, head=0x21d6c00, tail=0x21d6c00,
sched_job=00000000e3c2132f

[  328.871070] panfrost 1800000.gpu: Unhandled Page fault in AS0 at VA
0x0000000000000000
[  328.871070] Reason: TODO
[  328.871070] raw fault status: 0xAA0003C2
[  328.871070] decoded fault status: SLAVE FAULT
[  328.871070] exception type 0xC2: TRANSLATION_FAULT_LEVEL2
[  328.871070] access type 0x3: WRITE
[  328.871070] source id 0xAA00
[  329.373327] panfrost 1800000.gpu: gpu sched timeout, js=1,
config=0x3700, status=0x8, head=0xa1a4900, tail=0xa1a4900,
sched_job=000000007ac31097
[  329.386527] panfrost 1800000.gpu: js fault, js=0,
status=DATA_INVALID_FAULT, head=0xa1a4c00, tail=0xa1a4c00
[  329.396293] panfrost 1800000.gpu: gpu sched timeout, js=0,
config=0x3700, status=0x58, head=0xa1a4c00, tail=0xa1a4c00,
sched_job=0000000004c90381
[  329.411521] panfrost 1800000.gpu: Unhandled Page fault in AS0 at VA
0x0000000000000000
[  329.411521] Reason: TODO
[  329.411521] raw fault status: 0xAA0003C2
[  329.411521] decoded fault status: SLAVE FAULT
[  329.411521] exception type 0xC2: TRANSLATION_FAULT_LEVEL2
[  329.411521] access type 0x3: WRITE
[  329.411521] source id 0xAA00

Regards,
Clement

>
> > ---
> >  arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi | 80 ++++++++++++++++++++
> >  1 file changed, 80 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > index 8f514a2169aa..a69f9e09a829 100644
> > --- a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > +++ b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > @@ -174,6 +174,7 @@ gpu: gpu@1800000 {
> >                       clocks = <&ccu CLK_GPU>, <&ccu CLK_BUS_GPU>;
> >                       clock-names = "core", "bus";
> >                       resets = <&ccu RST_BUS_GPU>;
> > +                     operating-points-v2 = <&gpu_opp_table>;
> >                       #cooling-cells = <2>;
> >                       status = "disabled";
> >               };
> > @@ -1036,4 +1037,83 @@ map0 {
> >                       };
> >               };
> >       };
> > +
> > +     gpu_opp_table: gpu-opp-table {
> > +             compatible = "operating-points-v2";
> > +
> > +             opp@216000000 {
> > +                     opp-hz = /bits/ 64 <216000000>;
> > +                     opp-microvolt = <810000 810000 1200000>;
> > +             };
>
> All those nodes will create DTC warnings though.
>
> Maxime