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Subject: Re: [Freedreno] [PATCH] of/device: add blacklist for iommu dma_ops
To:     Rob Clark <robdclark@gmail.com>, Tomasz Figa <tfiga@chromium.org>
Cc:     freedreno <freedreno@lists.freedesktop.org>,
        Daniel Vetter <daniel@ffwll.ch>,
        Frank Rowand <frowand.list@gmail.com>,
        devicetree@vger.kernel.org, David Airlie <airlied@linux.ie>,
        linux-arm-msm <linux-arm-msm@vger.kernel.org>,
        Will Deacon <will.deacon@arm.com>,
        Doug Anderson <dianders@chromium.org>,
        dri-devel <dri-devel@lists.freedesktop.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Linux IOMMU <iommu@lists.linux-foundation.org>,
        Rob Herring <robh+dt@kernel.org>,
        Sean Paul <seanpaul@chromium.org>,
        Vivek Gautam <vivek.gautam@codeaurora.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Christoph Hellwig <hch@lst.de>
From:   Marek Szyprowski <m.szyprowski@samsung.com>
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Date:   Wed, 5 Jun 2019 15:18:10 +0200
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Hi Rob,

On 2019-06-05 14:57, Rob Clark wrote:
> On Tue, Jun 4, 2019 at 11:58 PM Tomasz Figa <tfiga@chromium.org> wrote:
>> But first of all, I remember Marek already submitted some patches long
>> ago that extended struct driver with some flag that means that the
>> driver doesn't want the IOMMU to be attached before probe. Why
>> wouldn't that work? Sounds like a perfect opt-out solution.
> Actually, yeah.. we should do that.  That is the simplest solution.

Tomasz has very good memory. It took me a while to find that old patches:

https://patchwork.kernel.org/patch/4677251/
https://patchwork.kernel.org/patch/4677941/
https://patchwork.kernel.org/patch/4677401/

It looks that my idea was a bit ahead of its time ;)

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland