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References: <20231127081511.1911706-1-lukasz.luba@arm.com>
In-Reply-To: <20231127081511.1911706-1-lukasz.luba@arm.com>
From:   Chen-Yu Tsai <wenst@chromium.org>
Date:   Mon, 27 Nov 2023 18:02:06 +0800
Message-ID: <CAGXv+5EgDk2B_FYo9hNiLVogq+mww1j140W4hsDhywExzgpf2g@mail.gmail.com>
Subject: Re: [PATCH] arm64: dts: rockchip: Add dynamic-power-coefficient to
 rk3399 GPU
To:     Lukasz Luba <lukasz.luba@arm.com>
Cc:     linux-kernel@vger.kernel.org, linux-rockchip@lists.infradead.org,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org,
        heiko@sntech.de, conor+dt@kernel.org, daniel.lezcano@linaro.org
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On Mon, Nov 27, 2023 at 4:14=E2=80=AFPM Lukasz Luba <lukasz.luba@arm.com> w=
rote:
>
> Add dynamic-power-coefficient to the GPU node. That will create Energy
> Model for the GPU based on the coefficient and OPP table information.
> It will enable mechanism such as DTMP or IPA to work with the GPU DVFS.
> In similar way the Energy Model for CPUs in rk3399 is created, so both
> are aligned in power scale. The maximum power used from this coefficient
> is 1.5W at 600MHz.
>
> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
> ---
>  arch/arm64/boot/dts/rockchip/rk3399.dtsi | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/boot/dts/rockchip/rk3399.dtsi b/arch/arm64/boot/d=
ts/rockchip/rk3399.dtsi
> index 9da0b6d77c8d..87cfdf570b19 100644
> --- a/arch/arm64/boot/dts/rockchip/rk3399.dtsi
> +++ b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
> @@ -2113,6 +2113,7 @@ gpu: gpu@ff9a0000 {
>                 interrupt-names =3D "job", "mmu", "gpu";
>                 clocks =3D <&cru ACLK_GPU>;
>                 #cooling-cells =3D <2>;
> +               dynamic-power-coefficient =3D <2640>;

For reference, in the ChromeOS downstrean v5.10 kernel we have:

gpu_power_model: power_model {
        compatible =3D "arm,mali-simple-power-model";
        static-coefficient =3D <411522>;
        dynamic-coefficient =3D <977>;
        ts =3D <32000 4700 (-80) 2>;
        thermal-zone =3D "gpu";
};

This is for the Mali kbase.

ChenYu

>                 power-domains =3D <&power RK3399_PD_GPU>;
>                 status =3D "disabled";
>         };
> --
> 2.25.1
>
>
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