From mboxrd@z Thu Jan  1 00:00:00 1970
From: nacc@linux.vnet.ibm.com (Nishanth Aravamudan)
Date: Wed, 14 Oct 2015 08:39:00 -0700
Subject: [PATCH 1/5 v2] dma-mapping: add generic dma_get_page_shift API
In-Reply-To: <20151012210651.GB26702@linux.vnet.ibm.com>
References: <20151002171606.GA41011@linux.vnet.ibm.com>
 <20151002200953.GB40695@linux.vnet.ibm.com>
 <20151002201142.GC40695@linux.vnet.ibm.com>
 <20151006095136.GB14144@infradead.org>
 <20151012210651.GB26702@linux.vnet.ibm.com>
Message-ID: <20151014153900.GC30179@linux.vnet.ibm.com>

Hi Christoph,

On 12.10.2015 [14:06:51 -0700], Nishanth Aravamudan wrote:
> On 06.10.2015 [02:51:36 -0700], Christoph Hellwig wrote:
> > Do we need a function here or can we just have a IOMMU_PAGE_SHIFT define
> > with an #ifndef in common code?
> 
> On Power, since it's technically variable, we'd need a function. So are
> you suggesting define'ing it to a function just on Power and leaving it
> a constant elsewhere?
> 
> I noticed that sparc has a IOMMU_PAGE_SHIFT already, fwiw.

Sorry, I should have been more specific -- I'm ready to spin out a v3,
with a sparc-specific function.

Are you ok with leaving it a function for now (the only caller is in
NVMe obviously).

-Nish