From mboxrd@z Thu Jan  1 00:00:00 1970
From: joro@8bytes.org (Joerg Roedel)
Date: Mon, 26 Jan 2015 14:47:01 +0100
Subject: [PATCH v5 11/18] iommu: exynos: remove useless device_add/remove
 callbacks
In-Reply-To: <1589480.9kxdoXKkuz@avalon>
References: <1422028288-891-1-git-send-email-m.szyprowski@samsung.com>
 <2829552.kzfCU5HyxQ@avalon> <20150126110059.GC30345@8bytes.org>
 <1589480.9kxdoXKkuz@avalon>
Message-ID: <20150126134701.GH30345@8bytes.org>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Hi Laurent,

On Mon, Jan 26, 2015 at 03:03:57PM +0200, Laurent Pinchart wrote:
> On Monday 26 January 2015 12:00:59 Joerg Roedel wrote:
> > My plan is to make IOMMU groups mandatory. I am currently preparing and
> > RFC patch-set to introduce default-domains (which will be per group). So
> > when all IOMMU drivers are converted to make use of default domains the
> > iommu groups will be mandatory.
> 
> Could the default domain policy be configured by the IOMMU driver ? The ipmmu-
> vmsa driver supports four domains only, and serves up to 32 masters, with one 
> group per master. A default of one domain per group wouldn't be usable.

I guess this limitation is a property of the iommu hardware. I currently
have no support for this in the patch-set, but I think it is easy (and
the best way) to support a model where we have only one default domain
for all groups. This is not in the patch set right now, but will be
added at some point.


	Joerg