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Date: Tue, 27 Oct 2015 19:30:28 -0700
From: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>,
 Michael Ellerman <mpe@ellerman.id.au>,
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 linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org,
 linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org
Subject: Re: [PATCH 2/7 v2] powerpc/dma-mapping: override dma_get_page_shift
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On 28.10.2015 [11:20:05 +0900], Benjamin Herrenschmidt wrote:
> On Tue, 2015-10-27 at 18:54 -0700, Nishanth Aravamudan wrote:
> > 
> > In "bypass" mode, what TCE size is used? Is it guaranteed to be 4K?
> 
> None :-) The TCEs are completely bypassed. You get a N:M linear mapping
> of all memory starting at 1<<59 PCI side.

Err, duh, sorry! Ok, so in that case, DMA page shift is PAGE_SHIFT,
then?

-Nish