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From:   Jon Mason <jdmason@kudzu.us>
Date:   Wed, 8 May 2019 18:56:46 +0100
Message-ID: <CAPoiz9zQuJ0-9wJBNo=Wvi9qquyid9vjmHODy=VJad_PE=cgdA@mail.gmail.com>
Subject: Re: status of the calgary iommu driver
To:     Christoph Hellwig <hch@lst.de>
Cc:     Muli Ben-Yehuda <mulix@mulix.org>, x86@kernel.org,
        iommu@lists.linux-foundation.org,
        linux-kernel <linux-kernel@vger.kernel.org>
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On Wed, May 8, 2019 at 6:52 PM Christoph Hellwig <hch@lst.de> wrote:
>
> On Wed, May 08, 2019 at 06:42:39PM +0100, Jon Mason wrote:
> > These systems were plentiful for 2-4 years after the original series
> > made it in.  After that, the Intel and AMD IOMMUs should were shipped
> > and were superior to this chip.  So, even in systems where these might
> > be present, the AMD/Intel ones should be used (unknown if they were
> > shipped on the same ones, as both Muli and I have left IBM).
> >
> > You thinking about removing the code?
>
> I'm wondering if we could remove it.  I've been done lots of
> maintainance on various dma mapping and iommu drivers, and the calgary
> one seems like it didn't get a whole lot of love, and I've not seen
> any recent users, so I mostly wonder if I should bother at all.


I do have a system.  So, it could be tested.  However given the age of
the HW, I would say it is not worth the effort to update and it would
be best to remove it from the kernel.

I can send a patch to do this, unless you would prefer to do it (or
already have something handy).

Thanks,
Jon