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Date: Thu, 06 Nov 2008 12:36:58 -0600
From: Bill Gatliff <bgat@billgatliff.com>
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To: Scott Wood <scottwood@freescale.com>
Subject: Re: Using DMA
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Cc: Bruce_Leonard@selinc.com, linuxppc-embedded@ozlabs.org
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Scott Wood wrote:
> Bruce_Leonard@selinc.com wrote:
>> In the Cafe driver, Linux Device Drivers 3rd Edition, and
>> DMA-mapping.txt everyone talks about how to allocate buffers using
>> dma/pci_alloc_coherent(), but no one talks about how to actually use
>> it. I'm pretty sure (even in my ignorance) that just allocating a DMA
>> coherent buffer and then copying in and out of it does NOT actually
>> engage the underlying hardware and perform a DMA transfer.

Does the "adma" stuff address this any?


b.g.
-- 
Bill Gatliff
bgat@billgatliff.com