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Date: Thu, 05 Dec 2002 18:49:10 +0100
From: Manfred Spraul <manfred@colorfullife.com>
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To: David Gibson <david@gibson.dropbear.id.au>
CC: linux-kernel@vger.kernel.org
Subject: Re: [RFC] generic device DMA implementation
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>
>
>Hmm... that doesn't seem sufficient to explain it.
>
>Some background: I work with PPC embedded chips (the 4xx family) whose
>only way to get consistent memory is by entirely disabling the cache.
>
What do you mean with "disable"?
Do you have to disable the cache entirely when you encounter the first 
pci_alloc_consistent() call, or do you disable the cache just for the 
region that is returned by pci_alloc_consistent()?

If you disable it entirely - would "before_acess_consistent_area() / 
after_access_consistent_area()" macros help to avoid that, or are there 
other problems?

--
    Manfred

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