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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Wed, 13 Nov 2019 08:38:15 +0100
Message-ID: <CAK8P3a3OpiWAep86tOiN1Fj2W7ud5hQ1OLTkBR8ueAKsMHk-dA@mail.gmail.com>
Subject: Re: [PATCH] video: fbdev: atyfb: only use ioremap_uc() on i386 and ia64
To:     Christoph Hellwig <hch@lst.de>
Cc:     Luis Chamberlain <mcgrof@kernel.org>,
        Daniel Vetter <daniel.vetter@ffwll.ch>,
        Juergen Gross <jgross@suse.com>,
        Tuowen Zhao <ztuowen@gmail.com>,
        AceLan Kao <acelan.kao@canonical.com>,
        Mika Westerberg <mika.westerberg@linux.intel.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Roman Gilg <subdiff@gmail.com>,
        Lee Jones <lee.jones@linaro.org>,
        "Luis R. Rodriguez" <mcgrof@suse.com>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
        X86 ML <x86@kernel.org>, Thomas Gleixner <tglx@linutronix.de>,
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On Wed, Nov 13, 2019 at 8:27 AM Christoph Hellwig <hch@lst.de> wrote:
>
> On Tue, Nov 12, 2019 at 10:24:23PM +0000, Luis Chamberlain wrote:
> > I think this would be possible if we could flop ioremap_nocache() to UC
> > instead of UC- on x86. Otherwise, I can't see how we can remove this by
> > still not allowing direct MTRR calls.
>
> If everything goes well ioremap_nocache will be gone as of 5.5.

As ioremap_nocache() just an alias for ioremap(), I suppose the idea would
then be to make x86 ioremap be UC instead of UC-, again matching what the
other architectures do already.

      Arnd