From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Lezcano Subject: Re: [PATCH] ARM: OMAP4: Fix the boot regression with CPU_IDLE enabled Date: Mon, 19 May 2014 20:06:31 +0200 Message-ID: <537A4827.30604@linaro.org> References: <5373DD94.8030208@ti.com> <5374F35E.5040900@ti.com> <5374FE61.50901@linaro.org> <5374FF5B.8050702@ti.com> <5375079E.3060305@ti.com> <537615EA.3020809@ti.com> <20140516212942.GK12881@atomide.com> <537A3544.1050307@linaro.org> <20140519172338.GJ4849@atomide.com> <537A408F.7070301@ti.com> <20140519175157.GK4849@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-we0-f181.google.com ([74.125.82.181]:46356 "EHLO mail-we0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751073AbaESSGV (ORCPT ); Mon, 19 May 2014 14:06:21 -0400 Received: by mail-we0-f181.google.com with SMTP id w61so5720710wes.26 for ; Mon, 19 May 2014 11:06:19 -0700 (PDT) In-Reply-To: <20140519175157.GK4849@atomide.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Tony Lindgren , Santosh Shilimkar Cc: Alex Shi , khilman@linaro.org, linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org, Roger Quadros On 05/19/2014 07:51 PM, Tony Lindgren wrote: > * Santosh Shilimkar [140519 10:35]: >> On Monday 19 May 2014 01:23 PM, Tony Lindgren wrote: >>> * Daniel Lezcano [140519 09:46]: >>>> On 05/16/2014 11:29 PM, Tony Lindgren wrote: >>>>> >>>>> And just to recap, this problem can be reproduced with current >>>>> Linux next with omap2plus_defconfig with CONFIG_CPU_IDLE enabled.= The >>>>> system should hang during the boot at some point. >>>> >>>> I can take the time to investigate a bit more but not right now. W= hat is >>>> your deadline before committing the reverts ? >>> >>> Well we do have several automated build and boot systems failing >>> because of this with multi_v7_defconfig. And users are complaining, >>> see this report from Tobias Jakobi: >>> >>> https://bugzilla.kernel.org/show_bug.cgi?id=3D75421 >>> >>> It seems that doing the revert is not enough based on the >>> page above. >>> >> Thats not true. The above link used the half patch and not the >> updated patch. Updated patch worked for Alex also. As you can >> see they saw RCU stalls and they go away after the updated patch. >> >> Can you please point them to try out the updated patch ? > > OK good point. I added a link to the updated patch in > bugzilla. > >>> I'd prefer we'd fix this issue properly for sure, it seems that >>> we're not quite understanding what's going on. And this might >>> hit other platforms too when they start implementing deeper >>> PM idle states in the mainline kernel. >>> >> I am certain that the updated patch fixed the regression >> for sure. The issue is really not generic enough since its related >> an OMAP ROM errata which needs that special handling of >> interrupt re-trigger etc. You don't need that for other platforms >> so they are not likely get affected. > > OK makes sense to me considering the ROM code. Daniel, are you OK > with that or do you still want to investigate further? =46or the moment I am a bit short in time for some other tasks. So feel= =20 free to apply the revert and I will look for a proper fix when I will=20 have time. Thanks -- Daniel --=20 Linaro.org =E2=94=82 Open source software fo= r ARM SoCs =46ollow Linaro: Facebook | Twitter | Blog -- To unsubscribe from this list: send the line "unsubscribe linux-omap" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html