From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:43178) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T4uhp-0001i2-D9 for qemu-devel@nongnu.org; Fri, 24 Aug 2012 10:17:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1T4uhl-0000hk-78 for qemu-devel@nongnu.org; Fri, 24 Aug 2012 10:17:49 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45830) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T4uhk-0000hg-Vg for qemu-devel@nongnu.org; Fri, 24 Aug 2012 10:17:45 -0400 Date: Fri, 24 Aug 2012 11:18:25 -0300 From: Luiz Capitulino Message-ID: <20120824111825.06484dd4@doriath.home> In-Reply-To: <201208232109.q7NL9P9t016424@int-mx09.intmail.prod.int.phx2.redhat.com> References: <201208232109.q7NL9P9t016424@int-mx09.intmail.prod.int.phx2.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] ahci: properly reset PxCMD on HBA reset List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jason Baron Cc: kwolf@redhat.com, aliguori@us.ibm.com, mst@redhat.com, qemu-devel@nongnu.org, jan.kiszka@siemens.com, agraf@suse.de, armbru@redhat.com, yamahata@valinux.co.jp, alex.williamson@redhat.com, pbonzini@redhat.com, afaerber@suse.de On Thu, 23 Aug 2012 17:09:25 -0400 Jason Baron wrote: > While testing q35, I found that windows 7 (specifically, windows 7 ultimate > with sp1 x64), wouldn't install because it can't find the cdrom or disk drive. > The failure message is: 'A required cd/dvd device driver is missing. If you > have a driver floppy disk, CD, DVD, or USB flash drive, please insert it now.' > This can also be reproduced on piix by adding an ahci controller, and > observing that windows 7 does not see any devices behind it. > > The problem is that when windows issues a HBA reset, qemu does not reset the > individual ports' PxCMD register. Windows 7 then reads back the PxCMD register > and presumably assumes that the ahci controller has already been initialized. > Windows then never sets up the PxIE register to enable interrupts, and thus it > never gets irqs back when it sends ata device inquiry commands. > > I believe this change brings qemu into ahci 1.3 specification compliance. I've tested this but unfortunately it doesn't fix the issues I'm getting with OpenBSD 5.1 and NetBSD 5.1 as reported here (section 'master with ahci'): http://lists.gnu.org/archive/html/qemu-devel/2012-08/msg03329.html PS: Those could be kernel issues, of course. > > Section 10.4.3 HBA Reset: > > " > When GHC.HR is set to '1', GHC.AE, GHC.IE, the IS register, and all port > register fields (except PxFB/PxFBU/PxCLB/PxCLBU) that are not HwInit in the > HBA's register memory space are reset. > " > > I've also re-tested Fedora 16 and 17 to verify that they continue to work with > this change. > > Signed-off-by: Jason Baron > --- > hw/ide/ahci.c | 1 + > 1 files changed, 1 insertions(+), 0 deletions(-) > > diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c > index 9fe89a5..06c236f 100644 > --- a/hw/ide/ahci.c > +++ b/hw/ide/ahci.c > @@ -1199,6 +1199,7 @@ void ahci_reset(AHCIState *s) > pr->irq_stat = 0; > pr->irq_mask = 0; > pr->scr_ctl = 0; > + pr->cmd = 0; > ahci_reset_port(s, i); > } > }