From mboxrd@z Thu Jan 1 00:00:00 1970 From: Torsten Kaiser Subject: Re: MSI broken in libata? Date: Sun, 10 Jan 2010 05:33:58 +0100 Message-ID: <64bb37e1001092033r1f0b4defw46c1a07101bb2d1b@mail.gmail.com> References: <64bb37e0912250122n4e0e1842q88c0dad7e99ec6a7@mail.gmail.com> <4B484829.6060405@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-fx0-f225.google.com ([209.85.220.225]:61469 "EHLO mail-fx0-f225.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750783Ab0AJEeA convert rfc822-to-8bit (ORCPT ); Sat, 9 Jan 2010 23:34:00 -0500 In-Reply-To: <4B484829.6060405@kernel.org> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: linux-kernel@vger.kernel.org, Jeff Garzik , linux-ide@vger.kernel.org On Sat, Jan 9, 2010 at 10:11 AM, Tejun Heo wrote: > On 12/25/2009 06:22 PM, Torsten Kaiser wrote: >> As reported in http://lkml.org/lkml/2009/12/19/82 the new MSI suppor= t >> for sata_sil24 does not work for me. >> This is still the same with 2.6.33-rc2. >> >> Why I think, this might be a problem within libata: >> =A0* other drivers can use MSI successful on my system (tg3, radeon,= hda-intel) >> =A0* happens both in sata_sil24 and sata_nv >> =A0* the count in /proc/interrupts increases for the MSIs assigned t= o >> sata_sil24/sata_nv, so interrupt delivery seems to work >> =A0* only writing seems to fail > > How does it fail? =A0Timeouts? Yes, timeouts. I posted the error messages in http://lkml.org/lkml/2009/12/19/82 and http://lkml.org/lkml/2010/1/6/60 > Also, ahci enables MSI by default if > available and works fine on many configurations so I don't think > anything in libata core layer is broken regarding MSI (there just > isn't anything which can break). The system I'm using does not have a ahci compatible controller, so I could not compare this. (And my other system that is using ahci, does not use MSI for that) I just found it suspicious that 3 other drivers (tg3, hda-intel and radeon) can use MSI, but both of the libata drivers (sata_sil24 and sata_nv) fail in a similar way. I did try the patch from Robert Hancock in http://lkml.org/lkml/2010/1/6/417 ,but without success. if you need any more information, or have something for me to try, please just ask. I did look at the code and the documentation about enabling MSI, but did not see anything (obvious) wrong, so I don't know what to try next. Torsten