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Message-ID: <1548904865.19710.37.camel@mhfsdcap03>
Subject: Re: [PATCH v5 19/20] iommu/mediatek: Add shutdown callback
From:   Yong Wu <yong.wu@mediatek.com>
To:     Evan Green <evgreen@chromium.org>
CC:     Joerg Roedel <joro@8bytes.org>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Robin Murphy <robin.murphy@arm.com>,
        Rob Herring <robh+dt@kernel.org>,
        Tomasz Figa <tfiga@google.com>,
        Will Deacon <will.deacon@arm.com>,
        <linux-mediatek@lists.infradead.org>,
        <srv_heupstream@mediatek.com>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>, LKML <linux-kernel@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <iommu@lists.linux-foundation.org>, Arnd Bergmann <arnd@arndb.de>,
        <yingjoe.chen@mediatek.com>, <youlin.pei@mediatek.com>,
        Nicolas Boichat <drinkcat@chromium.org>
Date:   Thu, 31 Jan 2019 11:21:05 +0800
In-Reply-To: <CAE=gft4g4HbDG7shtiqUP5vw9tiyRr4VEheMGM2uhEL_65yYmg@mail.gmail.com>
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On Wed, 2019-01-30 at 11:12 -0800, Evan Green wrote:
> On Mon, Dec 31, 2018 at 8:00 PM Yong Wu <yong.wu@mediatek.com> wrote:
> >
> > In the reboot burning test, if some Multimedia HW has something wrong,
> > It may keep send the invalid request to IOMMU. In order to avoid
> > affect the reboot flow, we add the shutdown callback to disable
> > M4U HW when shutdown.
> 
> Sounds unpleasant. Hopefully the reboot flow still continues properly
> even in that case, since this shutdown code may not run during some
> rougher resets.

Thanks this hint. I will reword the comment avoid writing reboot.

> 
> Reviewed-by: Evan Green <evgreen@chromium.org>

Thanks.