From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:38820) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T9xtS-0001YI-Gj for qemu-devel@nongnu.org; Fri, 07 Sep 2012 08:42:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1T9xtH-0005zm-5d for qemu-devel@nongnu.org; Fri, 07 Sep 2012 08:42:42 -0400 Received: from mx1.redhat.com ([209.132.183.28]:32539) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T9xtG-0005zg-Ry for qemu-devel@nongnu.org; Fri, 07 Sep 2012 08:42:31 -0400 Message-ID: <5049EBB0.9070907@redhat.com> Date: Fri, 07 Sep 2012 14:42:24 +0200 From: Kevin Wolf MIME-Version: 1.0 References: <201209042008.q84K88cJ015036@int-mx11.intmail.prod.int.phx2.redhat.com> <31DAB0D2-F7A5-4EC2-8199-9043660D0530@suse.de> In-Reply-To: <31DAB0D2-F7A5-4EC2-8199-9043660D0530@suse.de> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2] ahci: properly reset PxCMD on HBA reset List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexander Graf Cc: aliguori@us.ibm.com, mst@redhat.com, jan.kiszka@siemens.com, Jason Baron , qemu-devel@nongnu.org, armbru@redhat.com, yamahata@valinux.co.jp, alex.williamson@redhat.com, pbonzini@redhat.com, lcapitulino@redhat.com, afaerber@suse.de Am 05.09.2012 05:28, schrieb Alexander Graf: > > On 04.09.2012, at 16:08, 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. >> >> This change brings qemu into ahci 1.3 specification compliance. >> >> 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 > > Awesome, a lot cleaner now :). > > Acked-by: Alexander Graf Thanks, applied to block-next. Kevin