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Date: Thu, 14 Apr 2005 13:34:56 -0700
From: Julian Elischer <julian@elischer.org>
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To: Alexander Leidinger <Alexander@Leidinger.net>
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cc: freebsd-multimedia@freebsd.org
cc: Mathew Kanner <mat@cnd.mcgill.ca>
Subject: Re: de-dma uaudio
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Alexander Leidinger wrote:

> Mathew Kanner <mat@cnd.mcgill.ca> wrote:
>
>> On Apr 13, Kazuhito HONDA wrote:
>>
>>> Your idea is a fundamental and good one.
>>
>
>>     Great.  I've mentor approval to commit this, and I will
>> do so friday or saturday.
>
>
> Do I understand this patch right: it changes from DMA access to non-DMA
> access?
>
> If yes: can someone please explain me why this is a good thing?


The low hardware layer already does DMA to move data out of the
hardware to memory.  The data gets copied from the user layer to an 
intermediate
buffer and from there to the DMA buffers. There is no need to allocate 
DMA capable
buffers for the intermediate layer.


>
> Bye,
> Alexander.
>