From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC2C0C4360C for ; Wed, 16 Oct 2019 08:14:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 85328218DE for ; Wed, 16 Oct 2019 08:14:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571213653; bh=e94qyOW697j6Brhk1x91YtKXnJ2xd1o6sJyUcSKS//Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=fw/IcpGSYW3WMBiCKBOdV7NaG4jukSbVlx44DwWDP4UD5KBl29ScyQGKvxlax750n 6PbcrB7ByeMiNIzkp+smXUKffdhYzr/fg8LtkbADFE25kxB57hOlUhiU78GnSLalMa zlOVx285IVVdVl+sZZmKOMmFBLUHxfiLjku1B9ZQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389542AbfJPIOK (ORCPT ); Wed, 16 Oct 2019 04:14:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:54956 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727050AbfJPIOK (ORCPT ); Wed, 16 Oct 2019 04:14:10 -0400 Received: from localhost (unknown [171.76.123.182]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8CFAD2064B; Wed, 16 Oct 2019 08:14:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571213649; bh=e94qyOW697j6Brhk1x91YtKXnJ2xd1o6sJyUcSKS//Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Z97qQvbgnu8PYacVWHANHonUj8ddq5C7zHqQa80FkkFfSEkvw66E5b7Ghf5rZVQjQ sReLGNAMwosk+b+dOZGNykmUgDT+fcr/N8iXKlnLXPH21WvogC+IaO4n0Ev1BzdO8y Kj7/dWaJlT97a4c1xlLOaQsfFBzkv0OzFqC79B8k= Date: Wed, 16 Oct 2019 13:44:01 +0530 From: Vinod Koul To: Niklas Cassel Cc: Andy Gross , Bjorn Andersson , Rob Herring , Mark Rutland , linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] arm64: dts: qcom: qcs404-evb: Set vdd_apc regulator in high power mode Message-ID: <20191016081401.GI2654@vkoul-mobl> References: <20191014120920.12691-1-niklas.cassel@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191014120920.12691-1-niklas.cassel@linaro.org> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On 14-10-19, 14:09, Niklas Cassel wrote: > vdd_apc is the regulator that supplies the main CPU cluster. > > At sudden CPU load changes, we have noticed invalid page faults on > addresses with all bits shifted, as well as on addresses with individual > bits flipped. > > By putting the vdd_apc regulator in high power mode, the voltage drops > during sudden load changes will be less severe, and we have not been able > to reproduce the invalid page faults with the regulator in this mode. Reviewed-by: Vinod Koul This seems a good bug fix, maybe CC stable? > > Signed-off-by: Niklas Cassel > Suggested-by: Bjorn Andersson > --- > arch/arm64/boot/dts/qcom/qcs404-evb.dtsi | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/arm64/boot/dts/qcom/qcs404-evb.dtsi b/arch/arm64/boot/dts/qcom/qcs404-evb.dtsi > index 501a7330dbc8..522d3ef72df5 100644 > --- a/arch/arm64/boot/dts/qcom/qcs404-evb.dtsi > +++ b/arch/arm64/boot/dts/qcom/qcs404-evb.dtsi > @@ -73,6 +73,7 @@ > regulator-always-on; > regulator-boot-on; > regulator-name = "vdd_apc"; > + regulator-initial-mode = <1>; > regulator-min-microvolt = <1048000>; > regulator-max-microvolt = <1384000>; > }; > -- > 2.21.0 -- ~Vinod