Aw: Re: [RFC v1 14/14] arm64: dts: mediatek: mt7988: add operating-points

Frank Wunderlich frank-w at public-files.de
Wed Nov 27 07:06:26 PST 2024


> Gesendet: Mittwoch, 27. November 2024 um 14:34
> Von: "AngeloGioacchino Del Regno" <angelogioacchino.delregno at collabora.com>
> An: "Frank Wunderlich" <linux at fw-web.de>, "Rob Herring" <robh at kernel.org>, "Krzysztof Kozlowski" <krzk+dt at kernel.org>, "Conor Dooley" <conor+dt at kernel.org>, "Matthias Brugger" <matthias.bgg at gmail.com>
> CC: "Frank Wunderlich" <frank-w at public-files.de>, devicetree at vger.kernel.org, linux-kernel at vger.kernel.org, linux-arm-kernel at lists.infradead.org, linux-mediatek at lists.infradead.org
> Betreff: Re: [RFC v1 14/14] arm64: dts: mediatek: mt7988: add operating-points
>
> Il 29/10/24 11:39, Frank Wunderlich ha scritto:
> > From: Frank Wunderlich <frank-w at public-files.de>
> >
> > Add operating points defining frequency/voltages of cpu cores.
> >
> > Signed-off-by: Frank Wunderlich <frank-w at public-files.de>
> > ---
> >   arch/arm64/boot/dts/mediatek/mt7988a.dtsi | 45 +++++++++++++++++++++--
> >   1 file changed, 41 insertions(+), 4 deletions(-)
> >
> > diff --git a/arch/arm64/boot/dts/mediatek/mt7988a.dtsi b/arch/arm64/boot/dts/mediatek/mt7988a.dtsi
> > index e037854666c1..25669d498617 100644
> > --- a/arch/arm64/boot/dts/mediatek/mt7988a.dtsi
> > +++ b/arch/arm64/boot/dts/mediatek/mt7988a.dtsi
> > @@ -16,32 +16,69 @@ cpus {
> >   		#address-cells = <1>;
> >   		#size-cells = <0>;
> >
> > -		cpu at 0 {
> > +		cpu0: cpu at 0 {
>
> Where are those cpuX labels used? I don't see any usage.

these are used in later patch and needed in uboot when we want to switch to OF_UPSTREAM.

> >   			compatible = "arm,cortex-a73";
> >   			reg = <0x0>;
> >   			device_type = "cpu";
> >   			enable-method = "psci";
> > +			clocks = <&mcusys CLK_MCU_ARM_DIV_SEL>,
> > +				 <&topckgen CLK_TOP_XTAL>;
> > +			clock-names = "cpu", "intermediate";
> > +			operating-points-v2 = <&cluster0_opp>;
> >   		};
> >
> > -		cpu at 1 {
> > +		cpu1: cpu at 1 {
> >   			compatible = "arm,cortex-a73";
> >   			reg = <0x1>;
> >   			device_type = "cpu";
> >   			enable-method = "psci";
> > +			clocks = <&mcusys CLK_MCU_ARM_DIV_SEL>,
> > +				 <&topckgen CLK_TOP_XTAL>;
> > +			clock-names = "cpu", "intermediate";
> > +			operating-points-v2 = <&cluster0_opp>;
> >   		};
> >
> > -		cpu at 2 {
> > +		cpu2: cpu at 2 {
> >   			compatible = "arm,cortex-a73";
> >   			reg = <0x2>;
> >   			device_type = "cpu";
> >   			enable-method = "psci";
> > +			clocks = <&mcusys CLK_MCU_ARM_DIV_SEL>,
> > +				 <&topckgen CLK_TOP_XTAL>;
> > +			clock-names = "cpu", "intermediate";
> > +			operating-points-v2 = <&cluster0_opp>;
> >   		};
> >
> > -		cpu at 3 {
> > +		cpu3: cpu at 3 {
> >   			compatible = "arm,cortex-a73";
> >   			reg = <0x3>;
> >   			device_type = "cpu";
> >   			enable-method = "psci";
> > +			clocks = <&mcusys CLK_MCU_ARM_DIV_SEL>,
> > +				 <&topckgen CLK_TOP_XTAL>;
> > +			clock-names = "cpu", "intermediate";
> > +			operating-points-v2 = <&cluster0_opp>;
> > +		};
> > +
> > +		cluster0_opp: opp-table-0 {
> > +			compatible = "operating-points-v2";
> > +			opp-shared;
> > +			opp00 {
>
> ...But you can also be consistent with other devicetrees and follow the pattern
> for the node names of the OPP entries.
>
> opp-800000000
> opp-1100000000
> ...etc

ok, will change this..so just adding the opp-hz value to the name (or label)?

> Cheers,
> Angelo
>
> > +				opp-hz = /bits/ 64 <800000000>;
> > +				opp-microvolt = <850000>;
> > +			};
> > +			opp01 {
> > +				opp-hz = /bits/ 64 <1100000000>;
> > +				opp-microvolt = <850000>;
> > +			};
> > +			opp02 {
> > +				opp-hz = /bits/ 64 <1500000000>;
> > +				opp-microvolt = <850000>;
> > +			};
> > +			opp03 {
> > +				opp-hz = /bits/ 64 <1800000000>;
> > +				opp-microvolt = <900000>;
> > +			};
> >   		};
> >   	};
> >
>
>
> </frank-w at public-files.de></frank-w at public-files.de></frank-w at public-files.de></matthias.bgg at gmail.com></conor+dt at kernel.org></krzk+dt at kernel.org></robh at kernel.org></linux at fw-web.de></angelogioacchino.delregno at collabora.com>



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