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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D4A57C00144 for ; Mon, 1 Aug 2022 12:47:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231167AbiHAMrD (ORCPT ); Mon, 1 Aug 2022 08:47:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44412 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234979AbiHAMqo (ORCPT ); Mon, 1 Aug 2022 08:46:44 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DF356B76 for ; Mon, 1 Aug 2022 05:36:20 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8053961127 for ; Mon, 1 Aug 2022 12:36:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7F018C433D6; Mon, 1 Aug 2022 12:36:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1659357379; bh=kZCEGskqalhxUksNqAHxXa4wKsmMgGTM0zR1HJDxJeg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=nWwM21I5r6RewDjzByYaeHA/ymoaZz9e35S0xPyE4Dr846KRS93uvqNg1qZ2Ij2gv tsnB+g6oNIJnBkRMze8ubmlEDASesMb7oBKnw/gsE6BlwYuXfSqptCNmkccjNWBRe/ XiAfUoFBcnq6wgfpRmpGj5xW+9d9bkQiHTyqOyFws4SL7MtJlOZrioQv+gdnnFSzh0 54mvLsZZ8BcWHt+uk2TWzxCZGpzhxFGZia2mmbOrF0ovzF/UpdAdumgXsUXSIJlC5h z/wMpS9ST/H41tBXYfhLS/6GSnyLqoznhzdyU5jU+0X8wVdSgLnHXJF3gddtCWmrJC 30jgHAWweAPHA== Received: by pali.im (Postfix) id D8C9F75F; Mon, 1 Aug 2022 14:36:16 +0200 (CEST) Date: Mon, 1 Aug 2022 14:36:16 +0200 From: Pali =?utf-8?B?Um9ow6Fy?= To: Elad Nachman , Wojciech Bartczak Cc: Marek =?utf-8?B?QmVow7pu?= , Viresh Kumar , Gregory CLEMENT , Robert Marko , Tomasz Maciej Nowak , Anders Trier Olesen , Philip Soares , linux-pm@vger.kernel.org, Sebastian Hesselbarth , linux-arm-kernel@lists.infradead.org, nnet Subject: Re: [PATCH v2] cpufreq: armada-37xx: forbid cpufreq for 1.2 GHz variant Message-ID: <20220801123616.uol4wrs6trttumsg@pali> References: <20210630135942.29730-1-kabel@kernel.org> <20210630225601.6372-1-kabel@kernel.org> <20210702163035.nmb5pniwpqtmaz4b@pali> <20210708143451.4htvdop4zvjufrq6@pali> <20210715193321.z3vswz6x4rzvw2fd@pali> <20210808193026.xuyaufi5wqnrcakd@pali> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20210808193026.xuyaufi5wqnrcakd@pali> User-Agent: NeoMutt/20180716 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org + Elad and Wojciech from Marvell Could you please look at this issue and/or forward it to relevant Marvell team? Maintainer Viresh already wrote that we cannot hang forever for Marvell and patch which disables support for 1.2 GHz was merged: https://lore.kernel.org/linux-pm/20210809040224.j2rvopmmqda3utc5@vireshk-i7/ On Sunday 08 August 2021 21:30:26 Pali Rohár wrote: > Gentle reminder. This is really serious issue. Could you please look at it? > > Adding more MarvellEmbeddedProcessors people to the loop: Evan, Benjamin an Igal > > On Thursday 15 July 2021 21:33:21 Pali Rohár wrote: > > Ping! Gentle reminder for Marvell people. > > > > On Thursday 08 July 2021 16:34:51 Pali Rohár wrote: > > > Konstantin, Nadav, Ken, Victor, Jason: This issue is pretty serious, > > > CPU on 1.2GHz A3720 is crashing. Could you please look at it? > > > > > > On Friday 02 July 2021 18:30:35 Pali Rohár wrote: > > > > +Jason from GlobalScale as this issue affects GlobalScale Espressobin Ultra and V7 1.2 GHz boards. > > > > > > > > On Thursday 01 July 2021 00:56:01 Marek Behún wrote: > > > > > The 1.2 GHz variant of the Armada 3720 SOC is unstable with DVFS: when > > > > > the SOC boots, the WTMI firmware sets clocks and AVS values that work > > > > > correctly with 1.2 GHz CPU frequency, but random crashes occur once > > > > > cpufreq driver starts scaling. > > > > > > > > > > We do not know currently what is the reason: > > > > > - it may be that the voltage value for L0 for 1.2 GHz variant provided > > > > > by the vendor in the OTP is simply incorrect when scaling is used, > > > > > - it may be that some delay is needed somewhere, > > > > > - it may be something else. > > > > > > > > > > The most sane solution now seems to be to simply forbid the cpufreq > > > > > driver on 1.2 GHz variant. > > > > > > > > > > Signed-off-by: Marek Behún > > > > > Fixes: 92ce45fb875d ("cpufreq: Add DVFS support for Armada 37xx") > > > > > --- > > > > > If someone from Marvell could look into this, it would be great since > > > > > basically 1.2 GHz variant cannot scale, which is a feature that was > > > > > claimed to be supported by the SOC. > > > > > > > > > > Ken Ma / Victor Gu, you have worked on commit > > > > > https://github.com/MarvellEmbeddedProcessors/linux-marvell/commit/d6719fdc2b3cac58064f41b531f86993c919aa9a > > > > > in linux-marvell. > > > > > Your patch takes away the 1202 mV constant for 1.2 GHz base CPU > > > > > frequency and instead adds code that computes the voltages from the > > > > > voltage found in L0 AVS register (which is filled in by WTMI firmware). > > > > > > > > > > Do you know why the code does not work correctly for some 1.2 GHz > > > > > boards? Do we need to force the L0 voltage to 1202 mV if it is lower, > > > > > or something? > > > > > --- > > > > > drivers/cpufreq/armada-37xx-cpufreq.c | 6 +++++- > > > > > 1 file changed, 5 insertions(+), 1 deletion(-) > > > > > > > > > > diff --git a/drivers/cpufreq/armada-37xx-cpufreq.c b/drivers/cpufreq/armada-37xx-cpufreq.c > > > > > index 3fc98a3ffd91..c10fc33b29b1 100644 > > > > > --- a/drivers/cpufreq/armada-37xx-cpufreq.c > > > > > +++ b/drivers/cpufreq/armada-37xx-cpufreq.c > > > > > @@ -104,7 +104,11 @@ struct armada_37xx_dvfs { > > > > > }; > > > > > > > > > > static struct armada_37xx_dvfs armada_37xx_dvfs[] = { > > > > > - {.cpu_freq_max = 1200*1000*1000, .divider = {1, 2, 4, 6} }, > > > > > + /* > > > > > + * The cpufreq scaling for 1.2 GHz variant of the SOC is currently > > > > > + * unstable because we do not know how to configure it properly. > > > > > + */ > > > > > + /* {.cpu_freq_max = 1200*1000*1000, .divider = {1, 2, 4, 6} }, */ > > > > > {.cpu_freq_max = 1000*1000*1000, .divider = {1, 2, 4, 5} }, > > > > > {.cpu_freq_max = 800*1000*1000, .divider = {1, 2, 3, 4} }, > > > > > {.cpu_freq_max = 600*1000*1000, .divider = {2, 4, 5, 6} }, > > > > > -- > > > > > 2.31.1 > > > > >