Re: About MIPS specific dma_mmap_coherent()

[Ralf Baechle <ralf@linux-mips.org>]

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