GA-890FXA-UD5 IOMMU BIOS Switch?

[kuzew]

Hello,

I am attempting to do virtualization under Debian GNU/Linux (x86_64) using KVM (Kernel-based Virtual Machine). The Linux Kernel has the ability to utilize the Input/Output Memory Management Unit (IOMMU) [1,2] which is available in the northbridge chipset of the GA-890FXA-UD5 motherboard. The chipset, AMD 890FX (aka RD890) has been reported numerous times to support IOMMU [3,4,5,6] which made me go off to buy this motherboard, for this chipset. By using the IOMMU, I can do AGP and PCI passthrough to the virtual machine using the Graphics Address Remapping Table (GART), which is done by the IOMMU. Well, it seems I don't have IOMMU enabled, according the the boot logs on Linux.

Within the BIOS (version F2 (just updated)), there is only a switch for virtualization and that is it. Even under the "advanced" settings (Ctrl+F1) <ctrl><f1>there is still no switch for IOMMU related configurations.

So my question is (finally), will there be support for this option on this motherboard for this northbridge chipset in the near future? Or should I return this motherboard because it is just not wired for IOMMU and there is no way the BIOS vendor will support this? Or is it already setup and turned on (with no switch in the BIOS) for IOMMU and I'm just configuring Linux the wrong way (the hardware configuration is fine)? Am I doing something wrong here?

Thank you for your time and effort.
Cheers,

kuzew

[1] - IOMMU - Wikipedia, the free encyclopedia
[2] - I/O Virtualization and AMD's IOMMU
[3] - msicomputer 890FXA-GD70 PCSTATS Review - Introducing AMD 890FX and SB850 Chipsets
[4] - AMD 800 chipset series - Wikipedia, the free encyclopedia
[5] - Asus, Gigabyte, and MSI tackle AMD's 890FX chipset - The Tech Report - Page 1
[6] - 8-Series Chipsets, Revealed : AMD Phenom II X6 1090T And 890FX Platform Review: Hello, Leo</f1></ctrl>

[artdrivers]

Re: GA-890FXA-UD5 IOMMU BIOS Switch?

I don't know much about this but I will still offer some suggestions you may want to try.
Advanced BIOS Features enable Virtualization

Virtualization
Virtualization allows a platform to run multiple operating systems and applications in independent partitions. With virtualization, one computer system can function as multiple virtual systems.
(Default: Disabled)

Have you tried a Linux OS repair or update, install after enableing Virtualization in BIOS? Did you download and install the packages after Virtualization was enabled?
I know very little on this subject.

http://developer.amd.com/documentation/articles/pages/892006101.aspx

Now I know even less on this.

http://www.cyberciti.biz/tips/howto-turn-on-linux-software-iommu-support.html

[kuzew]

Re: GA-890FXA-UD5 IOMMU BIOS Switch?

I don't know much about this but I will still offer some suggestions you may want to try.
Advanced BIOS Features enable Virtualization
Have you tried a Linux OS repair or update, install after enableing Virtualization in BIOS? Did you download and install the packages after Virtualization was enabled?
I know very little on this subject.

Normal virtualization works just fine, I see the `svm` processor flag enabled when I do `cat /proc/cpuinfo`, so I know the basic virtualization is turned on and working just fine. I'm running KVM with no problems, but I do not have VGA or PCI passthrough to a Windows guest, which requires the IOMMU in the hardware. What I'm wondering about is the true support in the hardware for IOMMU. According to `dmesg` the kernel (2.6.34, just compiled with IOMMU support) complains about this:

...
[    0.000000] Checking aperture...
[    0.000000] No AGP bridge found
[    0.000000] Node 0: aperture @ 20000000 size 32 MB
[    0.000000] Aperture pointing to e820 RAM. Ignoring.
[    0.000000] Your BIOS doesn't leave a aperture memory hole
[    0.000000] Please enable the IOMMU option in the BIOS setup
[    0.000000] This costs you 64 MB of RAM
[    0.000000] Mapping aperture over 65536 KB of RAM @ 20000000
...

I just need to know, is IOMMU support really turned on in hardware on this motherboard? All reports I've read said yes and that there should be a switch for it in the BIOS. If there really is support turned on in the hardware, then I can go about working on getting the software to work correctly with the hardware. Otherwise I'm just wasting time with this current hardware.

Thanks for your input.
Cheers,

kuzew

[artdrivers]

Re: GA-890FXA-UD5 IOMMU BIOS Switch?

I'm Sorry I don't know. This question may be better suited for Gigabytes Technical Support Team. If you wish to send a ticket you should here from them in 2 bussiness days.
GIGABYTE GTS

[kuzew]

Re: GA-890FXA-UD5 IOMMU BIOS Switch?

I'm Sorry I don't know. This question may be better suited for Gigabytes Technical Support Team. If you wish to send a ticket you should here from them in 2 bussiness days.GIGABYTE GTS

Thanks for the suggestion... I submitted a ticket yesterday morning, though I didn't know about the two day latency, so I thought the service wasn't being used. I will post here the results of the ticket for anyone else having the same problem, or for general curiosity.

I'm really hoping that it is a software problem and that this feature really is turned on in the hardware OR that it can be turned on in the hardware with a BIOS update that it in the works. Otherwise I just blew lots of money on this expensive motherboard.

Thanks again, cheers!

kuzew

[Lsdmeasap]

Re: GA-890FXA-UD5 IOMMU BIOS Switch?

Yes, sadly sometimes it takes them 2-3 days or more to reply, they get MANY requests each day so it's hard to keep up.

If you find they do not reply after 4-5 days, send in another ticket.

[kuzew]

Re: GA-890FXA-UD5 IOMMU BIOS Switch?

Yes, sadly sometimes it takes them 2-3 days or more to reply, they get MANY requests each day so it's hard to keep up.

If you find they do not reply after 4-5 days, send in another ticket.

Thanks for the suggestions, I will keep that in mind if I don't hear back from them shortly.

I wonder, has anyone tried to read the MSR (model-specific registers) control registers on the processor to see if it can be enabled that way? Something to take after this: Enable VT-X on Mac Pro (Early 2008) - KVM

This is a really neat way to figure out what the machine is enabled to do and to potentially modify to get features turned on. Though I I highly doubt IOMMU can be enabled this way (it might be more complicated that I think), it would be cool to play around.

Cheers.

[joro80]

Re: GA-890FXA-UD5 IOMMU BIOS Switch?

...
[    0.000000] Checking aperture...
[    0.000000] No AGP bridge found
[    0.000000] Node 0: aperture @ 20000000 size 32 MB
[    0.000000] Aperture pointing to e820 RAM. Ignoring.
[    0.000000] Your BIOS doesn't leave a aperture memory hole
[    0.000000] Please enable the IOMMU option in the BIOS setup
[    0.000000] This costs you 64 MB of RAM
[    0.000000] Mapping aperture over 65536 KB of RAM @ 20000000
...

Hi,

I am the author of the Linux driver for the IOMMU, can you provide full dmesg of the boot and output of lspci? There we should see what the board provides to the OS.

joro

[kuzew]

Re: GA-890FXA-UD5 IOMMU BIOS Switch?

Hi,

I am the author of the Linux driver for the IOMMU, can you provide full dmesg of the boot and output of lspci? There we should see what the board provides to the OS.

joro

Sure thing!
I'm giving you `lspci -vvv` and just regular `dmesg` outputs.

dmesg: http://kuzew.net:81/~tmp/890fx_iommu/dmesg.out
lspci -vvv: http://kuzew.net:81/~tmp/890fx_iommu/lspci_vvv.out

Should we move to a mailing list?

Cheers,

kuzew

[joro80]

Re: GA-890FXA-UD5 IOMMU BIOS Switch?

Hmm, thats very sad :-( No IOMMU ACPI table is present (IVRS) and even the PCI device for the IOMMU itself is not enabled. The device would show up in lspci as device 00:00.2 if it where present.

[artdrivers]

Re: GA-890FXA-UD5 IOMMU BIOS Switch?

The BIOS has a ACPI suspend type in the Power Mangement Setup. Here are the default values. Maybe a change in it will help.

Power Management Setup
ACPI Suspend Type [S3(STR)]
Soft-Off by Power button [Instant-off]
USB Wake Up from S3 [Enabled]
Modem Ring Resume [Disabled]
PME Event Wake Up [Enabled]
HPET Support (Note) [Enabled]
Power On By Mouse [Disabled]
Power On By Keyboard [Disabled]
x KB Power ON Password Enter
AC Back Function [Soft-Off]
Power-On by Alarm [Disabled]
x Date (of Month) Everyday
x Resume Time (hh:mm:ss) 0 : 0 : 0
ErP Support [Disabled]

[kuzew]

Re: GA-890FXA-UD5 IOMMU BIOS Switch?

Hmm, thats very sad :-( No IOMMU ACPI table is present (IVRS) and even the PCI device for the IOMMU itself is not enabled. The device would show up in lspci as device 00:00.2 if it where present.

Yeah, I was reading the IOMMU spec from AMD and the BIOS needs to describe the IOMMU in a ACPI table, which therefore leads me to believe that the BIOS is broken for this 890FX chipset. I'm fairly sure that this chipset has the capability for this feature, it is just not turned on in the BIOS -- or I could be totally wrong.

So, where do I go from here? What can I do to help get this enable? I've already submitted a ticket to Gigabyte complaining about this. Do you know of anyone else that has this same chipset as I but *has* IOMMU enabled and working? Is there still hope to get this working?

Thanks a whole lot for looking in to this for me.

Cheers!

[kuzew]

Re: GA-890FXA-UD5 IOMMU BIOS Switch?

The BIOS has a ACPI suspend type in the Power Mangement Setup. Here are the default values. Maybe a change in it will help.

Power Management Setup
ACPI Suspend Type [S3(STR)]

That is dealing with the power interface part of ACPI (Advanced Configuration and Power Interface). The different S-types deal with the different power states of the system. IIRC S3 is sleep or rather, suspend to ram. Here is a good detailed explanation: Advanced Configuration and Power Interface - Wikipedia, the free encyclopedia

I /could/ try, but I doubt that the power settings will enable IOMMU. Thank you anyway.

[jdma]

Re: GA-890FXA-UD5 IOMMU BIOS Switch?

I was not able to get iommu to work on my MSI 890FXA-GD70. Before I purchased, an MSI rep told me that the motherboard is supposed to support it, but it looks like they did not implement the necessary bios support either. I am waiting to hear back from them as to when/if they plan to add support, so I would not recommend swapping for this board until I hear more.

[joro80]

Re: GA-890FXA-UD5 IOMMU BIOS Switch?

Yeah, I was reading the IOMMU spec from AMD and the BIOS needs to describe the IOMMU in a ACPI table, which therefore leads me to believe that the BIOS is broken for this 890FX chipset. I'm fairly sure that this chipset has the capability for this feature, it is just not turned on in the BIOS -- or I could be totally wrong.

No, the BIOS vendor just don't support it. You can try to complain to them so that they may support it in a future BIOS version.

So, where do I go from here? What can I do to help get this enable? I've already submitted a ticket to Gigabyte complaining about this. Do you know of anyone else that has this same chipset as I but *has* IOMMU enabled and working? Is there still hope to get this working?

I am looking for an 890FX board which has IOMMU support in the BIOS myself. I will try to ask the motherboard vendors too if they want to build in support into their BIOSes.
I also want to have an IOMMU system at home :-)

Cheers.