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Date: Mon, 27 Apr 2009 13:00:09 -0700
From: David Hawkins <dwh@ovro.caltech.edu>
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Subject: Re: [PATCH] fsldma: use PCI Read Multiple command
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>> Can you give me an example of non-PCI memory that would be
>> non-prefetchable that you'd like us to try? We can see if our
>> host CPUs have an area like that ... we just need to know
>> what device to look for first :)
> 
> You can mark the pci inbound window on the 83xx as non-prefetchable 
> (assuming 83xx is host). On a x86 host I doubt there is any easy way to 
> get non-prefetchable memory.

Yep, we were going to do that, but chose to use the
1MB region already setup for the IMMRs since its already
marked as non-prefetchable. We were only doing reads, so
it wasn't going to hurt anything.

I doubt that marking one of the other BAR regions
as non-prefetchable will give a different result.
However, we're more than happy to double-check if
you'd like.

Cheers,
Dave