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Date: Wed, 6 Jul 2011 10:37:37 -0400 (EDT)
From: Nicolas Pitre <nicolas.pitre@linaro.org>
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To: Russell King - ARM Linux <linux@arm.linux.org.uk>
cc: Arnd Bergmann <arnd@arndb.de>, "'Daniel Walker'" <dwalker@codeaurora.org>,
        "'Jonathan Corbet'" <corbet@lwn.net>, "'Mel Gorman'" <mel@csn.ul.ie>,
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Subject: Re: [Linaro-mm-sig] [PATCH 6/8] drivers: add Contiguous Memory
 Allocator
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On Wed, 6 Jul 2011, Russell King - ARM Linux wrote:

> Another issue is that when a platform has restricted DMA regions,
> they typically don't fall into the highmem zone.  As the dmabounce
> code allocates from the DMA coherent allocator to provide it with
> guaranteed DMA-able memory, that would be rather inconvenient.

Do we encounter this in practice i.e. do those platforms requiring large 
contiguous allocations motivating this work have such DMA restrictions?


Nicolas