Re: [PATCH] pci: Reenable the AMD IOMMU if it's mysteriouslyvanished over suspend

[Matthew Garrett]

On Thu, Sep 30, 2010 at 08:43:01PM +0200, Joerg Roedel wrote:

> Enabling the IOMMU device is only part of what the BIOS is supposed to
> do to get the IOMMU ready for the OS. A handful of registers in the
> config space of the device and the IOMMU MMIO region must also be
> restored. Thats the simple part. The IOMMU device also spans two
> indirect register spaces to configure the IOMMU caches. I have no idea
> yet how this need to be configured. The plan is definitly to
> work-around a missing IOMMU device in the IOMMU driver. But I am still
> talking to some people to find out what exactly must be done, especially
> with the indirect register spaces.

Chapter 8 of the register setup guide seems to have something on this - 
I'll try saving and restoring all of the setup it performs to see if it 
improves things.

-- 
Matthew Garrett | mjg59@xxxxxxxxxxxxx
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