From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andre Przywara Subject: Re: IOMMU and AMD 890fx Date: Thu, 3 Jun 2010 13:51:05 +0200 Message-ID: <4C079729.8030502@amd.com> References: <3399D2269986104B959D31B7E919313C06E2BD8E@SAUSEXMBP01.amd.com> <4410545273.20100510083852@eikelenboom.it> <571239012.20100603101930@eikelenboom.it> <1857fd65263c9155e5f307f3b7e329d0.squirrel@www.boonen.name> <1807175740.20100603112310@eikelenboom.it> <20100603112649.GG11162@8bytes.org> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20100603112649.GG11162@8bytes.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Joerg Roedel Cc: Leonardo Prosperi , =?ISO-8859-1?Q?Jens_Krehbiel-Gr=E4ther?= , "Huang2, Wei" , Sander Eikelenboom , "xen-devel@lists.xensource.com" , Joop Boonen List-Id: xen-devel@lists.xenproject.org Hi, J=F6rg is correct, thanks for picking this up. Some additions inline. Joerg Roedel wrote: > Hello Jens, >=20 > On Thu, Jun 03, 2010 at 12:51:23PM +0200, Jens Krehbiel-Gr=E4ther wrote= : >> I got this answer from asrock support: >> >> >> So, I get more/final answer from Taiwan department: >> >> For H/W part: >> >From chipset spec, RD890(890FX) did support IOMMU. >> But IOMMU also need CPU to support. >=20 > Thats wrong. The IOMMU is a feature of the chipset northbridge and does > not need additional cpu support. >=20 >> Till now, AMD has no plan to support >> IOMMU on desktop CPU (AM3 socket). >=20 > There are AM3 boards out there with server a chipset that have it > enabled. Its no question of a socket. That would be the Tyan S8005, although the official CPU support list=20 only lists Opteron parts (those in AM3 socket: Suzuka and Budapest) >=20 >> It only support with server CPU. >=20 > Also wrong. I have seen systems with desktop cpus that have IOMMU > enabled (Phenom X4 and Phenom X6). >=20 >> For BIOS part: >=20 >> AMD has removed IOMMU related registers. >=20 > Hard to believe. I have found people in the net who say that the ASUS > Crosshair IV mobo has IOMMU support in the BIOS. So if they can enable > it, asrock can do that too. Its just the BIOS which has to enable it If you want to check this yourself: For out-of-the-box support there needs to be an ACPI table called IVRS=20 setup by the BIOS, you can spot this in xm dmesg (or in dmesg on native=20 Linux): (XEN) ACPI: IVRS C7E7ACC8, 00E0 (r1 AMD RD890S 6040000 AMD = 0) On a native Linux you can also find the table in /sys/firmware/acpi/table= s If the table is present, recent Xen versions (as well as Linux and KVM)=20 should automatically enable and use the IOMMU. If the ACPI table is missing, you can try to look for the corresponding=20 PCI device: it should have a vendor/device-id of 1002:5a23, lspci lists=20 it as: 00:00.2 Generic system peripheral [0806]: ATI Technologies Inc Device 5a2= 3 If anyone has a board with the PCI device but a missing ACPI table,=20 please tell us. We are already trying to improve the situation, you could help us by=20 reporting the IOMMU support status on 890FX boards. Simply check for the=20 ACPI table: # xm dmesg | grep IVRS or $ ls /sys/firmware/acpi/tables/IVRS and by checking for the PCI device: $ /sbin/lspci -d 1002:5a23 Hope that helps. Regards, Andre. --=20 Andre Przywara AMD-Operating System Research Center (OSRC), Dresden, Germany Tel: +49 351 448 3567 12 ----to satisfy European Law for business letters: Advanced Micro Devices GmbH Einsteinring 24, 85609 Dornach b. Muenchen Geschaeftsfuehrer: Andrew Bowd; Thomas M. McCoy; Giuliano Meroni Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen Registergericht Muenchen, HRB Nr. 43632