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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Mon, 9 Apr 2018 14:54:30 +0200
Message-ID: <CAMuHMdUy6C4OoGF44e_34+XjsQHe6RwfoesfBzcM8baEHUwzXw@mail.gmail.com>
Subject: Re: [PATCH 03/12] m68k/mac: Don't remap SWIM MMIO region
To:     Finn Thain <fthain@telegraphics.com.au>
Cc:     Laurent Vivier <lvivier@redhat.com>, Jens Axboe <axboe@kernel.dk>,
        linux-m68k <linux-m68k@lists.linux-m68k.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Hi Finn,

On Sun, Apr 1, 2018 at 3:41 AM, Finn Thain <fthain@telegraphics.com.au> wrote:
> For reasons I don't understand, calling ioremap() then iounmap() on
> the SWIM MMIO region causes a hang on 68030 (but not on 68040).

Michael Schmitz also notices strange things with ioremap() on '030.

> There's no need to call ioremap() for the SWIM address range, as it lies
> within the usual IO device region at 0x5000 0000, which is already mapped.

by head.S, right?

> --- a/drivers/block/swim.c
> +++ b/drivers/block/swim.c
> @@ -911,7 +911,7 @@ static int swim_probe(struct platform_device *dev)
>                 goto out;
>         }
>
> -       swim_base = ioremap(res->start, resource_size(res));
> +       swim_base = (struct swim __iomem *)res->start;

I guess you need a __force to please sparse?

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