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From:   Leonard Crestez <leonard.crestez@nxp.com>
To:     Anson Huang <anson.huang@nxp.com>,
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Subject: Re: [PATCH 2/2] arm64: dts: imx8mm: Assign highest opp as suspend opp
Thread-Topic: [PATCH 2/2] arm64: dts: imx8mm: Assign highest opp as suspend
 opp
Thread-Index: AQHVMjEDVn995bhE70i5OsdReRFRhA==
Date:   Thu, 4 Jul 2019 07:49:07 +0000
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References: <20190704061403.8249-1-Anson.Huang@nxp.com>
 <20190704061403.8249-2-Anson.Huang@nxp.com>
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On 7/4/2019 9:23 AM, Anson.Huang@nxp.com wrote:=0A=
> From: Anson Huang <Anson.Huang@nxp.com>=0A=
> =0A=
> Assign highest OPP as suspend OPP to reduce suspend/resume=0A=
> latency on i.MX8MM.=0A=
> =0A=
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>=0A=
> ---=0A=
>   arch/arm64/boot/dts/freescale/imx8mm.dtsi | 1 +=0A=
>   1 file changed, 1 insertion(+)=0A=
> =0A=
> diff --git a/arch/arm64/boot/dts/freescale/imx8mm.dtsi b/arch/arm64/boot/=
dts/freescale/imx8mm.dtsi=0A=
> index b11fc5e..3a62407 100644=0A=
> --- a/arch/arm64/boot/dts/freescale/imx8mm.dtsi=0A=
> +++ b/arch/arm64/boot/dts/freescale/imx8mm.dtsi=0A=
> @@ -136,6 +136,7 @@=0A=
>   			opp-microvolt =3D <1000000>;=0A=
>   			opp-supported-hw =3D <0x8>, <0x3>;=0A=
>   			clock-latency-ns =3D <150000>;=0A=
> +			opp-suspend;=0A=
>   		};=0A=
>   	};=0A=
=0A=
What if the highest OPP is unavailable due to speed grading? Ideally we =0A=
should find a way to suspend at the highest *supported* OPP.=0A=
=0A=
Maybe the opp-suspend marking could be assigned from imx-cpufreq-dt =0A=
driver code?=0A=
=0A=
--=0A=
Regards,=0A=
Leonard=0A=
=0A=