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Date: Tue, 30 Jan 2024 15:29:13 -0600
From: Bjorn Andersson <andersson@kernel.org>
To: Lucas Karpinski <lkarpins@redhat.com>
Cc: Andy Gross <agross@kernel.org>, 
	Konrad Dybcio <konrad.dybcio@linaro.org>, Rob Herring <robh+dt@kernel.org>, 
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>, Conor Dooley <conor+dt@kernel.org>, 
	linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] arm64: dts: qcom: sa8540p-ride: disable pcie2a node
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On Tue, Jan 09, 2024 at 10:20:50AM -0500, Lucas Karpinski wrote:
> pcie2a and pcie3a both cause interrupt storms to occur. However, when
> both are enabled simultaneously, the two combined interrupt storms will
> lead to rcu stalls. Red Hat is the only company still using this board
> and since we still need pcie3a, just disable pcie2a.
> 

Why are there interrupt storms? What interrupt(s) is(are) involved?

Do you consider this a temporary fix?

Are you okay with pcie3a misbehaving?

Regards,
Bjorn

> Signed-off-by: Lucas Karpinski <lkarpins@redhat.com>
> ---
> v2:
> - don't remove the entire pcie2a node, just set status to disabled.
> - update commit message.
> 
>  arch/arm64/boot/dts/qcom/sa8540p-ride.dts | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sa8540p-ride.dts b/arch/arm64/boot/dts/qcom/sa8540p-ride.dts
> index b04f72ec097c..177b9dad6ff7 100644
> --- a/arch/arm64/boot/dts/qcom/sa8540p-ride.dts
> +++ b/arch/arm64/boot/dts/qcom/sa8540p-ride.dts
> @@ -376,14 +376,14 @@ &pcie2a {
>  	pinctrl-names = "default";
>  	pinctrl-0 = <&pcie2a_default>;
>  
> -	status = "okay";
> +	status = "disabled";
>  };
>  
>  &pcie2a_phy {
>  	vdda-phy-supply = <&vreg_l11a>;
>  	vdda-pll-supply = <&vreg_l3a>;
>  
> -	status = "okay";
> +	status = "disabled";
>  };
>  
>  &pcie3a {
> -- 
> 2.43.0
>