From: Jesse Barnes <jesse.barnes@intel.com>
To: Andi Kleen <andi@firstfloor.org>
Subject: Re: [Intel IOMMU 00/10] Intel IOMMU support, take #2
Date: Tue, 26 Jun 2007 13:10:15 -0700
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Cc: Arjan van de Ven <arjan@linux.intel.com>,
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       ashok.raj@intel.com, davem@davemloft.net, clameter@sgi.com
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On Tuesday, June 26, 2007 10:31:57 Andi Kleen wrote:
> > >>(and I think it mostly already doesn't even without that)
> > >
> > >It uses /sys/bus/pci/* which is not any better as seen from the
> > > IOMMU.
> > >
> > >Any interface will need to be explicit because user space needs to
> > > know which
> > >DMA addresses to put into the hardware. It's not enough to just
> > >transparently
> > >translate the mappings.
> >
> > that's what DRM is used for nowadays...
>
> But DRM does support much less hardware than the X server?

Yeah, the number of DRM drivers is relatively small compared to X or 
fbdev, but for simple DMA they're fairly easy to write.

> Perhaps we just need an ioctl where an X server can switch this.

Switch what?  Turn on or off transparent translation?

Jesse
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