From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755201AbbI0IVH (ORCPT ); Sun, 27 Sep 2015 04:21:07 -0400 Received: from down.free-electrons.com ([37.187.137.238]:47708 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753896AbbI0IVC (ORCPT ); Sun, 27 Sep 2015 04:21:02 -0400 Date: Sun, 27 Sep 2015 10:20:58 +0200 From: Maxime Ripard To: Timo Sigurdsson Cc: khilman@kernel.org, robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, linux@arm.linux.org.uk, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-sunxi@googlegroups.com, wens@csie.org, tyler.baker@linaro.org, olof@lixom.net Subject: Re: [PATCH v2] ARM: dts: sunxi: Add regulators for LeMaker BananaPi Message-ID: <20150927082058.GF7104@lukather> References: <1438532305-5884-1-git-send-email-public_timo.s@silentcreek.de> <20150818153631.GH2547@lukather> <20150925150558.184E66C8385C@dd34104.kasserver.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="XIiC+We3v3zHqZ6Z" Content-Disposition: inline In-Reply-To: <20150925150558.184E66C8385C@dd34104.kasserver.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --XIiC+We3v3zHqZ6Z Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Sep 25, 2015 at 05:05:58PM +0200, Timo Sigurdsson wrote: > Hi Kevin, >=20 > Kevin Hilman schrieb am 25. Sept 2015 01:57: >=20 > > On Tue, Aug 18, 2015 at 8:36 AM, Maxime Ripard > > wrote: > >> On Sun, Aug 02, 2015 at 06:18:25PM +0200, Timo Sigurdsson wrote: > >>> sun7i-a20-bananapi.dts doesn't contain regulator nodes for the AXP209 > >>> PMU > >>> driver, so add them to allow for voltage-scaling with cpufreq-dt. > >>> > >>> Signed-off-by: Timo Sigurdsson > >> > >> Queued, thanks! > >> Maxime > >=20 > > kernelci.org started finding boot faiulres[1] on bananapi linux-next > > around next-20150918, but it was only failing in some labs and not > > others. I finally bisected it down to this patch, which landed in > > linux-next in the form of 2d665a8a8350 ARM: dts: sunxi: Add regulators > > for LeMaker BananaPi. Reverting that commit on top of next-20150923 > > gets my bananapi booting again. > >=20 > > Note it's kind of an interesting boot failure. The kernel boots fully > > to a shell, but panics after running a few commands. In particular > > 'dmesg -n1' seems to trigger it usually[2]. > >=20 > > Kevin > >=20 > > [1] > > http://kernelci.org/boot/sun7i-a20-bananapi/job/next/kernel/next-201509= 23/defconfig/multi_v7_defconfig/lab/lab-khilman/?_id=3D5602504359b514be146c= 326f > > [2] > > http://storage.kernelci.org/next/next-20150923/arm-multi_v7_defconfig/l= ab-khilman/boot-sun7i-a20-bananapi.html > >=20 >=20 > Thanks for your feedback. I'm traveling at the moment, so I can't do > any testing but just guess wildly. I know, though, that I used dmesg > frequently when I did my own testing before submitting the patch and > could not see such behavior. >=20 > Before this commit, the CPU of your BananaPi runs at 1.4 volts > constantly. With this commit applied, the CPU voltage should vary > between 1.0-1.4 volts depending on the frequency and defined > operating points. Hence, one of my guesses would be that your CPU is > not stable at the lower voltages. Could you modify the voltages for > the defined frequencies in sun7i-a20.dtsi and test if that solves > your issue? Say, raise the voltage by 0.1 volts for each operating > point (but no higher than 1.4). I actually had a different patch > that applied slightly higher voltages taken from the original fex > for by LeMaker, but the feedback was, unless there are actual > reports about boards not running stable at the current settings, we > just keep them instead. So, I'm curious if you happen to have a > board that requires slightly higher voltages to run stable. I've dropped the patch waiting for you to come back from your holidays when we will have more time to figure out what's wrong. Thanks! Maxime --=20 Maxime Ripard, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com --XIiC+We3v3zHqZ6Z Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJWB6bqAAoJEBx+YmzsjxAgc0oP/Ru9vvWjzUFudX/HU6fY110m nvqC2HX2RzI9kMLuDQW5nA+7L+FPtVfGN/oGuiYsGbH/U5slk83FpcMnZ1cJZ98N S+1iM80HBtkj4NBOcc6pTo+qrt9o1ou6IMYR8BOYsH5GfKtYDBDeInQ4xInmREsI YHKcqEUhDSEt8PdhacnjaSeM9KzReDx4ADMOgCm3J0G89t6GM3LL0x7POShQBuSA f0CQnA4Zoy8xJb+1vUjbW00lyXsF2bqfACU8vFZgW8lyQp5AePRueZNBdJTv2dl0 54TJLiU74n1OPkkZ/+YpAhAzDxhMAKbeJnDeczKYnYeckwxYZccfK1kLaULHtcrP rTQKKbni5ha3a+ocOSNnxW7bBUYJKoj+iqAeLDQswyyyc7IwaMyG6DQGXSobGNTZ xlpCbtNxPg4NnSD0szyf8kG0YEtSPNTUFu0nUbPb5TMi7tOiZ8jY//7Hqz616DKn CZ62VkS/wuUfQpCsO615WYvdlL5bd7IVc+QpwUSBmhRNMfJ25pC0y+3Je3fM2MHP u3je3AroxrRfDeP4di4SX8/qxMejzkZjm34RGx6il5MPFlSLPEzTz2GqhTRq4Jbx DAZTS7frVrTWJkDfLRacAwcEO4aPuY08wHKsemnCvZ3jyMm3eVKEFhm2Ck4bEjNu 3wagI+fGbF2I+a2MEq2K =msO4 -----END PGP SIGNATURE----- --XIiC+We3v3zHqZ6Z--