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Message-ID: <ccc45d36-0c87-742c-4105-56820b058040@baylibre.com>
Date:   Mon, 4 Apr 2022 09:50:37 +0200
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Subject: Re: [PATCH v2 2/2] arm64: dts: meson: remove CPU opps below 1GHz for
 SM1 boards
Content-Language: en-US
To:     Christian Hewitt <christianshewitt@gmail.com>,
        Rob Herring <robh+dt@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Kevin Hilman <khilman@baylibre.com>,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-amlogic@lists.infradead.org, linux-kernel@vger.kernel.org
References: <20220210100638.19130-1-christianshewitt@gmail.com>
 <20220210100638.19130-3-christianshewitt@gmail.com>
From:   Neil Armstrong <narmstrong@baylibre.com>
Organization: Baylibre
In-Reply-To: <20220210100638.19130-3-christianshewitt@gmail.com>
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On 10/02/2022 11:06, Christian Hewitt wrote:
> Amlogic SM1 devices experience CPU stalls and random board wedges when
> the system idles and CPU cores clock down to lower opp points. Recent
> vendor kernels include a change to remove 100-250MHz and other distro
> sources also remove the 500/667MHz points. Unless all 100-667Mhz opps
> are removed or the CPU governor forced to performance stalls are still
> observed, so let's remove them to improve stability and uptime.
> 
> Fixes: 3d9e76483049 ("arm64: dts: meson-sm1-sei610: enable DVFS")
> Signed-off-by: Christian Hewitt <christianshewitt@gmail.com>
> ---
>   arch/arm64/boot/dts/amlogic/meson-sm1.dtsi | 20 --------------------
>   1 file changed, 20 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/amlogic/meson-sm1.dtsi b/arch/arm64/boot/dts/amlogic/meson-sm1.dtsi
> index 3c07a89bfd27..80737731af3f 100644
> --- a/arch/arm64/boot/dts/amlogic/meson-sm1.dtsi
> +++ b/arch/arm64/boot/dts/amlogic/meson-sm1.dtsi
> @@ -95,26 +95,6 @@
>   		compatible = "operating-points-v2";
>   		opp-shared;
>   
> -		opp-100000000 {
> -			opp-hz = /bits/ 64 <100000000>;
> -			opp-microvolt = <730000>;
> -		};
> -
> -		opp-250000000 {
> -			opp-hz = /bits/ 64 <250000000>;
> -			opp-microvolt = <730000>;
> -		};
> -
> -		opp-500000000 {
> -			opp-hz = /bits/ 64 <500000000>;
> -			opp-microvolt = <730000>;
> -		};
> -
> -		opp-667000000 {
> -			opp-hz = /bits/ 64 <666666666>;
> -			opp-microvolt = <750000>;
> -		};
> -
>   		opp-1000000000 {
>   			opp-hz = /bits/ 64 <1000000000>;
>   			opp-microvolt = <770000>;

Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>