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Date:   Tue, 11 May 2010 19:48:44 +0100
From:   Ralf Baechle <ralf@linux-mips.org>
To:     Takashi Iwai <tiwai@suse.de>
Cc:     wuzhangjin@gmail.com, linux-mips <linux-mips@linux-mips.org>
Subject: Re: About MIPS specific dma_mmap_coherent()
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On Wed, Apr 14, 2010 at 05:46:13PM +0200, Takashi Iwai wrote:

> But, I remember vaguely that calling pgprot_noncached()
> unconditionally is dangerous.  It should be checked somehow, e.g. via
> platform_device_is_coherent().  And, this found only in
> dma-coherence.h, and adding it to pcm_native.c would become messy like
> below...
> 
> So, it'd be really better to add dma_mmap_coherent(), indeed.

We agreed that this was only meant as a stop gap meassure.  As such I do
agree with either of

  http://patchwork.linux-mips.org/patch/1117/
  http://patchwork.linux-mips.org/patch/1118/

Wu has tested the 1117 patch so that might make it preferable especially
for 2.6.34 if we should go for that.

  Ralf