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Date: Mon, 10 Jun 2002 03:24:01 -0700 (PDT)
Message-Id: <20020610.032401.21500297.davem@redhat.com>
To: oliver@neukum.name
Cc: linux-kernel@vger.kernel.org
Subject: Re: PCI DMA to small buffers on cache-incoherent arch
From: "David S. Miller" <davem@redhat.com>
In-Reply-To: <200206101200.14109.oliver@neukum.name>
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   From: Oliver Neukum <oliver@neukum.name>
   Date: Mon, 10 Jun 2002 12:00:14 +0200

   > You flush either before/after depending upon whether the cpu caches
   > are writeback in nature or not, and the cpu is not allowed to touch
   > those addresses while the device is doing the DMA.
   
   So we need some kind of cache_aligned macro in our USB data
   structures if they contain a buffer. Which macro would we have to use ?

For now use SMP_CACHE_BYTES I guess.
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