Re: [PATCH 1/2] arm64: dts: rk3328: add gpu opp table

[Nicolas Frattaroli <frattaroli.nicolas@gmail.com>]

On Dienstag, 19. Oktober 2021 17:52:05 CEST Alex Bee wrote:
> Am 18.10.21 um 18:49 schrieb Nicolas Frattaroli:
> > On Samstag, 16. Oktober 2021 17:45:44 CEST Trevor Woerner wrote:
> >> Add an operating-points table and cooling entry to the GPU on the
> >> RK3328 SoC to improve its performance. According to its datasheet[1]
> >> the maximum frequency of the Mali-450 MP2 GPU found on the RK3328 SoC
> >> is 500MHz.
> >>
> >> On my rock64 device, under x11, glmark2-es2 performance increased from
> >> around 60 to just over 100. Same device running glmark2-es2 under
> >> wayland/weston improved from just over 100 to just over 200.
> >>
> >> [1] https://rockchip.fr/RK3328%20datasheet%20V1.2.pdf
> >>
> >> Signed-off-by: Trevor Woerner <twoerner@gmail.com>
> >> ---
> >>   arch/arm64/boot/dts/rockchip/rk3328.dtsi | 26 +++++++++++++++++++++++-
> >>   1 file changed, 25 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/arch/arm64/boot/dts/rockchip/rk3328.dtsi
> >> b/arch/arm64/boot/dts/rockchip/rk3328.dtsi index 8c821acb21ff..5e1dcf71e414
> >> 100644
> >> --- a/arch/arm64/boot/dts/rockchip/rk3328.dtsi
> >> +++ b/arch/arm64/boot/dts/rockchip/rk3328.dtsi
> >> @@ -532,7 +532,8 @@ map0 {
> >>   					cooling-device = <&cpu0
> > THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> >>   							 <&cpu1
> > THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> >>   							 <&cpu2
> > THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> >> -							 <&cpu3
> > THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> >> +							 <&cpu3
> > THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
> >> +							 <&gpu
> > THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> >>   					contribution = <4096>;
> >>   				};
> >>   			};
> >> @@ -617,6 +618,29 @@ gpu: gpu@ff300000 {
> >>   		clocks = <&cru ACLK_GPU>, <&cru ACLK_GPU>;
> >>   		clock-names = "bus", "core";
> >>   		resets = <&cru SRST_GPU_A>;
> >> +		operating-points-v2 = <&gpu_opp_table>;
> >> +		#cooling-cells = <2>;
> >> +	};
> >> +
> >> +	gpu_opp_table: gpu-opp-table {
> >> +		compatible = "operating-points-v2";
> >> +
> >> +		opp-200000000 {
> >> +			opp-hz = /bits/ 64 <200000000>;
> >> +			opp-microvolt = <1100000>;
> >> +		};
> >> +		opp-300000000 {
> >> +			opp-hz = /bits/ 64 <300000000>;
> >> +			opp-microvolt = <1100000>;
> >> +		};
> >> +		opp-400000000 {
> >> +			opp-hz = /bits/ 64 <400000000>;
> >> +			opp-microvolt = <1100000>;
> >> +		};
> >> +		opp-500000000 {
> >> +			opp-hz = /bits/ 64 <500000000>;
> >> +			opp-microvolt = <1100000>;
> >> +		};
> >>   	};
> >>
> >>   	h265e_mmu: iommu@ff330200 {
> > 
> > As for whether this works as described on a ROCK64 for glmark2-es2-wayland:
> 
> The probably most "convenient" and also future-proof solution upstream 
> for that is to define voltage ranges á la
> 
> 
> 
> opp-200000000 {
> 
> 		opp-hz = /bits/ 64 <200000000>;
> 
> 		opp-microvolt = <950000 950000 1150000>;
> 
> 
> 
> };
> 
> and so on.
> 
> And then adapt the regulator-min-microvolt of the logic regulator like
> 
> vdd_logic: DCDC_REG1 {
> 
> 	regulator-name = "vdd_logic";
> 
> 	regulator-min-microvolt = <1050000>;
> 
> ...
> };
> 
> That way all opp-points will be taken, but its ensured, that vdd_log 
> never goes below 1.05 V
> 
> > 
> > Tested-by: Nicolas Frattaroli <frattaroli.nicolas@gmail.com>
> > 
> > There is some stuff worth noting that LibreELEC does on this SoC[1]:
> > 
> > 1. they use 1.05V for all OPPs up to and including 400 MHz
> > 2. they run 500 MHz at 1.15V instead (though 1.10V seemed to work for both of
> > us)
> 
> That might be true for your boards, but note that the required voltage 
> is per "leakage level" defined in efuse bits - something we do not 
> support for Rockchip upstream currently - see [1]

Thank you for the insight.

If we had the efuse bits, is there an already existing mechanism to only
enable the 500 MHz OPP if the chip happens to be one of those able to do
it at 1.10V?

Something like only having opp-microvolt-L1 defined and having the opp
be ignored if we're not an L1 chip.

> 
> > 3. they disable 500 MHz because 1.15V was apparently too high for rkvdec.
> > 
> > 3 is currently not very relevant because mainline Linux has no rkvdec node in
> > the rk3328 dtsi, and we're not running at 1.15V.
> > 
> > I've decided to add their rkvdec dtsi patch[2] on top anyway, and saw no
> > complaints from the rkvdec module while glmark2-es2-drm was running. However,
> > it's not like I tried to actually hardware decode video while it was running
> > because the userspace situation still won't let me without compiling entirely
> > too much stuff from git. Though the rkvdec module was loaded and present.
> You will see no complaints from the module , but you will see the SoC 
> crashing if both is running at the same time - see rkvdec-opp-table 
> downstream [2]

I did end up finding an old arm64 build I had of a patched ffmpeg that works
for the current kernel, and

  ffmpeg -hwaccel drm -i file -f null -

was running stably with glmark2-es2-drm running at the same time, though I
also did not have an rkvdec OPP table.

Either way, thank you for clearing things up. I guess the easiest way to
get more useful clocks on mainline right now is to disable the 500 MHz
OPP and define them all in the way you've suggested.

Regards,
Nicolas Frattaroli

> 
> [1] 
> https://github.com/rockchip-linux/kernel/blob/develop-4.4/arch/arm64/boot/dts/rockchip/rk3328.dtsi#L750-L751
> 
> [2] 
> https://github.com/rockchip-linux/kernel/blob/develop-4.4/arch/arm64/boot/dts/rockchip/rk3328.dtsi#L840-L867
> 
> Alex
> 
> > [1]: https://github.com/LibreELEC/LibreELEC.tv/commit/
> > 9a6be0d36ba7ff3c3d5df798682d47a1de594ac0
> > [2]: https://github.com/LibreELEC/LibreELEC.tv/blob/master/projects/Rockchip/
> > patches/linux/default/linux-1001-v4l2-rockchip.patch#L860-L935
> > 
> > 
> > 
> > 
> > _______________________________________________
> > Linux-rockchip mailing list
> > Linux-rockchip@lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-rockchip
> > 
> 
> 





_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel