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Subject: Re: [PATCH] powerpc/mm: add ZONE_NORMAL zone for 64 bit kernel
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Tabi Timur-B04825 <B04825@freescale.com>
Date: Tue, 24 Jul 2012 09:12:25 +1000
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On Mon, 2012-07-23 at 23:08 +0000, Tabi Timur-B04825 wrote:
> 
> > And ? Who cares ? Drivers who know about a 32-bit limitations use
> > GFP_DMA32, that's what is expected, don't mess around with ZONE_DMA.
> 
> I thought drivers are supposed to set a dma_mask, and
> dma_alloc_coherent() is supposed to use that to figure out how to
> honor that mask.

Sure, that's the right way to go, I meant bits of pieces of the
infrastructure in between. Why diverge from other archs gratuituously
here ?

Cheers,
Ben.