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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Mon, 28 Jun 2021 21:12:58 +0200
Message-ID: <CAMuHMdVT17ruQZKJXAahMvQQVMnJNoaSjHSuqat-CHOCV4hVaA@mail.gmail.com>
Subject: Re: dma_declare_coherent_memory and SuperH
To:     Christoph Hellwig <hch@lst.de>
Cc:     Rob Landley <rob@landley.net>,
        Yoshinori Sato <ysato@users.sourceforge.jp>,
        Rich Felker <dalias@libc.org>,
        Linux-sh list <linux-sh@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Hi Christoph,

On Mon, Jun 28, 2021 at 6:33 PM Christoph Hellwig <hch@lst.de> wrote:
> On Mon, Jun 28, 2021 at 09:29:59AM -0500, Rob Landley wrote:
> > > No.  My hope is to kill dma_declarare_coherent, an API for board
> > > support files to declare device-specific regions to be used for
> > > coherent DMA.
> >
> > Q) If I haven't got regression test hardware to make sure I properly converted
> > each of these entire boards to device tree, Is there anything else I can do to
> > help you remove this function from common code, such as inlining some portion of
> > this function?
> >
> > A) You can convert the board to device tree.
> >
> > Which part of this exchange have I misunderstood?
>
> The part that there is no easy way out without the device tree
> conversion.

So you keep this functionality around with DT.  Which means there's
some code to parse the DT, extract a region, and handle it?
I'm just wondering which terrible maintenance burden would be left by
making the handling function public, so the SH platform code can still call it?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds