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Date: Wed, 18 May 2005 18:24:04 -0700
From: Eugene Surovegin <ebs@ebshome.net>
To: Shawn Jin <shawnxjin@gmail.com>
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Cc: ppcembed <linuxppc-embedded@ozlabs.org>
Subject: Re: DMA consistent allocation is limited to 2MB on 2.6.11 for
	ppc440?
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On Wed, May 18, 2005 at 05:54:39PM -0700, Shawn Jin wrote:
> The page table 'consistent_pte' covers the uncached DMA consistent
> allocation space. Its size is only one page, each page has 512 PTEs.
> That means only 2MB memory are available for DMA. For some
> applications this is not enough. So how to eliminate this limitation?

No, _all_ physical memory is available for DMA. "consistent" pool is 
used for small non-cached allocations, e.g. buffer descriptors, etc. 
Don't use it for actual data buffers.

-- 
Eugene