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Subject: Re: [PATCH 02/12] fs_enet: Add MPC5121 FEC support.
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Grant Likely <grant.likely@secretlab.ca>
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Date: Tue, 19 May 2009 08:17:31 +1000
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On Thu, 2009-05-14 at 08:00 -0600, Grant Likely wrote:
> 
> All of this doesn't actually affect the driver code at all.  It's all
> handled by the kernel and the DMA apis.  What it does affect is
> multiplatform kernels.  The DMA behaviour is set at compile time, not
> run time, depending on the setting of CONFIG_NON_COHERENT_CACHE (see
> arch/powerpc/platforms/Kconfig.cputype).  A kernel which has it on
> won't run properly on a platform which has it off, and visa-versa.

We are close to the point where we can make this a runtime option
though, by just having a different set of dma_ops hooked in.

Cheers,
Ben.