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=-6.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 A2597C388F9 for ; Thu, 19 Nov 2020 11:33:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3BCF02100A for ; Thu, 19 Nov 2020 11:33:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="KSMYoLed" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726898AbgKSLdK (ORCPT ); Thu, 19 Nov 2020 06:33:10 -0500 Received: from mail.kernel.org ([198.145.29.99]:38474 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726760AbgKSLdK (ORCPT ); Thu, 19 Nov 2020 06:33:10 -0500 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (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 CBB7A20867; Thu, 19 Nov 2020 11:33:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605785589; bh=IwzuzZJdgwM/mSCg/YGq4DFiccAa0AMjMOfLhF3JG8I=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=KSMYoLedOZpStbTVjCff3VA/bScZg/ZBa6KN2hth62ft0nkMImZm0kHTF5TDUuxCj 8rQwrf/w655P5dRXoelEcF1FC8r9D+7nMXVCDEv3HaDhKKjvQJ9u9NmQg1lZbGu2BT Z8cIAWKKIxlLFh7MZ+3urSr8owbFL0odZfYyGCpI= Received: from disco-boy.misterjones.org ([51.254.78.96] helo=www.loen.fr) by disco-boy.misterjones.org with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94) (envelope-from ) id 1kfiBW-00Bw2g-MO; Thu, 19 Nov 2020 11:33:06 +0000 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Date: Thu, 19 Nov 2020 11:33:06 +0000 From: Marc Zyngier To: Neil Armstrong Cc: Guillaume Tucker , kernelci-results@groups.io, Kevin Hilman , Jerome Brunet , linux-arm-kernel@lists.infradead.org, linux-amlogic@lists.infradead.org, Martin Blumenstingl , David Airlie , Daniel Vetter , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: next/master bisection: baseline.dmesg.emerg on meson-gxbb-p200 In-Reply-To: <3f54de27-0fef-c5a1-8991-0a0614c90667@baylibre.com> References: <5fb5e094.1c69fb81.a2014.2e62@mx.google.com> <630e00e83cdd07ee5a0eaba9d3479554@kernel.org> <3f54de27-0fef-c5a1-8991-0a0614c90667@baylibre.com> User-Agent: Roundcube Webmail/1.4.9 Message-ID: <48731911dbbe869a6d3bdafd819fa9ff@kernel.org> X-Sender: maz@kernel.org X-SA-Exim-Connect-IP: 51.254.78.96 X-SA-Exim-Rcpt-To: narmstrong@baylibre.com, guillaume.tucker@collabora.com, kernelci-results@groups.io, khilman@baylibre.com, jbrunet@baylibre.com, linux-arm-kernel@lists.infradead.org, linux-amlogic@lists.infradead.org, martin.blumenstingl@googlemail.com, airlied@linux.ie, daniel@ffwll.ch, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-11-19 10:26, Neil Armstrong wrote: > On 19/11/2020 11:20, Marc Zyngier wrote: >> On 2020-11-19 08:50, Guillaume Tucker wrote: >>> Please see the automated bisection report below about some kernel >>> errors on meson-gxbb-p200. >>> >>> Reports aren't automatically sent to the public while we're >>> trialing new bisection features on kernelci.org, however this one >>> looks valid. >>> >>> The bisection started with next-20201118 but the errors are still >>> present in next-20201119.  Details for this regression: >>> >>>   https://kernelci.org/test/case/id/5fb6196bfd0127fd68d8d902/ >>> >>> The first error is: >>> >>>   [   14.757489] Internal error: synchronous external abort: 96000210 >>> [#1] PREEMPT SMP >> >> Looks like yet another clock ordering setup. I guess different Amlogic >> platforms have slightly different ordering requirements. >> >> Neil, do you have any idea of which platform requires which ordering? >> The variability in DT and platforms is pretty difficult to follow (and >> I don't think I have such board around). > > The requirements should be the same, here the init was done before > calling > dw_hdmi_probe to be sure the clocks and internals resets were > deasserted. > But since you boot from u-boot already enabling these, it's already > active. The crashing platform also boots with u-boot. What is the difference? No HDMI support? > The solution would be to revert and do some check in > meson_dw_hdmi_init() to > check if already enabled and do nothing. It looks more subtle than that, as it also depends on which DT is provided (an early meson_dw_hdmi_init() works with the kernel DT, and breaks with the u-boot DT). So whatever difference is between the two DTs causes havoc. u-boot obviously only uses its own DT, so we are looking at a kernel bug here. Not having this patch also breaks module reinsertion (HDMI clocks are disabled on unbind), so *something* has to be done late. So here are my questions: - What breaks in my config when I boot using u-boot's DT? - How to detect early that the registers are clocked or not? Thanks, M. -- Jazz is not dead. It just smells funny...