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Date: Mon, 29 Aug 2011 15:05:52 +0200
From: "Roedel, Joerg" <Joerg.Roedel@amd.com>
To: Ohad Ben-Cohen <ohad@wizery.com>
CC: "iommu@lists.linux-foundation.org" <iommu@lists.linux-foundation.org>,
        Stepan Moskovchenko <stepanm@codeaurora.org>,
        David Woodhouse <dwmw2@infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        David Brown <davidb@codeaurora.org>
Subject: Re: [PATCH] iommu: Remove stub functions for !CONFIG_IOMMU_API
Message-ID: <20110829130552.GA10422@amd.com>
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On Mon, Aug 29, 2011 at 08:55:40AM -0400, Ohad Ben-Cohen wrote:
> On Mon, Aug 29, 2011 at 3:25 PM, Roedel, Joerg <Joerg.Roedel@amd.com> wrote:
> > Right, when the system has an iommu then the iommu-api is the right
> > choice to do that. But how to you handle this on systems without an
> > iommu?
> 
> On iommu-less systems this is completely moot, as the remote processor
> can access the bus directly, and thus doesn't need any iommu
> configuration to take place before it boots.
> 
> So in case there is an iommu - we configure it appropriately, and if
> there isn't, we just skip that part.

So in this case you can skip this whole part when CONFIG_IOMMU_API is
disabled (just don't compile the code in that requires the iommu-api).
This saves you even more .text size, no?

	Joerg

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