Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752013AbbHBJI7 (ORCPT ); Sun, 2 Aug 2015 05:08:59 -0400 Received: from mail-wi0-f169.google.com ([209.85.212.169]:35126 "EHLO mail-wi0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751849AbbHBJI4 (ORCPT ); Sun, 2 Aug 2015 05:08:56 -0400 From: Pali =?utf-8?q?Roh=C3=A1r?= To: Robert Hancock Subject: Re: linux: sata_nv: adma support Date: Sun, 2 Aug 2015 11:08:52 +0200 User-Agent: KMail/1.13.7 (Linux/3.13.0-61-generic; KDE/4.14.2; x86_64; ; ) Cc: Jeff Garzik , Robert Hancock , Tejun Heo , "linux-ide@vger.kernel.org" , "linux-kernel" References: <201412232051.07067@pali> <201508012209.27974@pali> In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart23588778.S0bNN1V6oX"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <201508021108.52978@pali> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6114 Lines: 159 --nextPart23588778.S0bNN1V6oX Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Sunday 02 August 2015 03:45:32 Robert Hancock wrote: > On Sat, Aug 1, 2015 at 2:09 PM, Pali Roh=C3=A1r > wrote: > > On Thursday 25 December 2014 07:22:13 Robert Hancock wrote: > >> On Tue, Dec 23, 2014 at 1:51 PM, Pali Roh=C3=A1r > >>=20 > >> wrote: > >> > Hello, > >> >=20 > >> > I have nvidia nforce4 motherboard with nvidia sata controller: > >> >=20 > >> > 00:07.0 IDE interface [0101]: NVIDIA Corporation CK804 Serial > >> > ATA Controller [10de:0054] (rev f3) > >> > 00:08.0 IDE interface [0101]: NVIDIA Corporation CK804 Serial > >> > ATA Controller [10de:0055] (rev f3) > >> >=20 > >> > I manually enabled adma mode (which is disabled by default) by > >> > adding sata_nv.adma=3D1 to grub cmdline. In git history I found > >> > that enabling adma mode includes NCQ support and reduced CPU > >> > overhead. It looks like adma mode is working, but at every boot > >> > I see one same error message in dmesg: > >> >=20 > >> > [ 16.823514] ata1.00: exception Emask 0x1 SAct 0x0 SErr 0x0 > >> > action 0x0 > >> > [ 16.823520] ata1.00: CPB resp_flags 0x11: , CMD error > >> > [ 16.823524] ata1.00: failed command: SET FEATURES > >> > [ 16.823530] ata1.00: cmd ef/05:fe:00:00:00/00:00:00:00:00/40 > >> > tag 16 > >> > [ 16.823530] res 51/04:fe:00:00:00/00:00:00:00:00/40 > >> > Emask 0x1 (device error) > >> > [ 16.823533] ata1.00: status: { DRDY ERR } > >> > [ 16.823535] ata1.00: error: { ABRT } > >> >=20 > >> > When adma is disabled then this error message is not generated. > >>=20 > >> It looks like something is trying to issue a command to disable > >> APM power management on the drive, and the command fails (likely > >> because it doesn't support that command). I'm not sure where that > >> would be coming from - I'm pretty sure the kernel doesn't issue > >> that command itself. Something that's part of your distro > >> perhaps? > >>=20 > >> I don't know why it would only be failing in ADMA mode either, > >> though depending on where the command is coming from, maybe it's > >> not being issued otherwise for some reason? > >>=20 > >> > What does that error message means? It is critical? What is that > >> > command SET FEATURES doing? Are there any problems with adma > >> > mode on nforce4 motherboards? Because I did not see any > >> > problems (except that one error message). > >> >=20 > >> > -- > >> > Pali Roh=C3=A1r > >> > pali.rohar@gmail.com > >=20 > > Hello, > >=20 > > now after long time I did more investigation and that error is > > reported for every connected HDD. I identified that it comes from > > udev script > >=20 > > /lib/udev/rules.d/85-hdparm.rules > >=20 > > which just call script /lib/udev/hdparm for every one connected > > HDD. > >=20 > > Script /lib/udev/hdparm just call: > > /sbin/hdparm -B254 $DRIVE > >=20 > > And that -B254 cause above error message in dmesg log. Output from > >=20 > > hdparm is: > > /dev/sda: > > setting Advanced Power Management level to 0xfe (254) > > APM_level =3D not supported > >=20 > > Any idea why in ADMA mode it cause above error (APM unsupported) > > and in non ADMA mode it is working fine? Maybe APM ATA commands > > should not be sent via ADMA? > >=20 > > Here is another output: > > $ sudo hdparm -I /dev/sda | grep -i power > > =20 > > * Power Management feature set > > =20 > > Power-Up In Standby feature set > > =20 > > * SET_FEATURES required to spinup after power up > > * Host-initiated interface power management >=20 > The "set features" command is a non-data command so based on our > current knowledge, it should work in ADMA mode. However, these NVIDIA > SATAs are black boxes, and rather buggy ones at that, so it's > possible there's an unknown issue there. >=20 Maybe I should note that hdparm -I did not generated any error message.=20 I post is here because it show "Power Management feature set" is=20 supported by HDD. This indicate that HDD supports -B (APM) command,=20 right? > The easiest way to test that would be to take out the condition check > for qc->tf.protocol =3D=3D ATA_PROT_NODATA in nv_adma_use_reg_mode in > drivers/ata/sata_nv.c. That would force it to disable ADMA for all > non-data commands. >=20 Ok, as now I have just SSH access to that machine, I will do kernel=20 patching later (when I have physical access to it). > I really don't know why Ubuntu is disabling APM on all drives on > bootup however. Especially for laptops, that seems like a silly thing > to do explicitly. Sounds like one of the silly things Ubuntu is known > to do without consulting people. Looks like this comes from upstream udev/systemd project :-( Anyway, for=20 laptops on battery ubuntu has another set of scripts which turn on APM=20 (based on connected/disconnected AC adapter). That udev script which turn off APM is called when any disk is attached=20 to system (so at boot time it is called for every one disk). Now I just masked that udev script and it is no longer called... Anyway if I call hdparm -B /dev/sda I get output: APM_level =3D not supported And important is that there is no error message in dmesg. I get it only=20 if I call hdparm -B with parameter (set option). But APM should be=20 supported, right? =2D-=20 Pali Roh=C3=A1r pali.rohar@gmail.com --nextPart23588778.S0bNN1V6oX Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iEYEABECAAYFAlW93iQACgkQi/DJPQPkQ1IxcwCgweUDMf906q2gtfmv0BLzegmh rncAoJR1zHaP8GfMYcFMnzPd74vGU5vA =O8qP -----END PGP SIGNATURE----- --nextPart23588778.S0bNN1V6oX-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/