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From: robherring2@gmail.com (Rob Herring)
To: linux-arm-kernel@lists.infradead.org
Subject: Cortex A9 with ACP needing mixed coherency model
Date: Fri, 24 Aug 2012 08:05:50 -0500	[thread overview]
Message-ID: <50377C2E.4080408@gmail.com> (raw)
In-Reply-To: <20120824085440.GC5400@mudshark.cambridge.arm.com>

On 08/24/2012 03:54 AM, Will Deacon wrote:
> On Fri, Aug 24, 2012 at 01:58:50AM +0100, John Linn wrote:
>> It doesn't look like there's any good way to have a mixed coherency
>> model to support using the ACP where there is coherency and using
>> other ports where there is not coherency.
>> ARM Linux kernel can support arch_is_coherent(), which means all DMA
>> I/O is coherent. We have multiple DMA engines and they can go to thru
>> coherent or non-coherent ports.
>>
>> Am I missing something, or has someone figured out a way to deal with this?
> 
> Didn't Rob have a crack at fixing this with his recent DMA series?
> 
>   http://lists.infradead.org/pipermail/linux-arm-kernel/2012-August/113929.html
> 
> It's a really nice set of patches, so take a look.

It's queued up in Marek's dma-mapping tree for 3.7.

Rob

      reply	other threads:[~2012-08-24 13:05 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-08-24  0:58 Cortex A9 with ACP needing mixed coherency model John Linn
2012-08-24  8:54 ` Will Deacon
2012-08-24 13:05   ` Rob Herring [this message]

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