Re: [PATCH v2 2/4] asm-generic/io.h: Remove unused generic __ioremap() definition

Re: [PATCH v2 2/4] asm-generic/io.h: Remove unused generic __ioremap() definition

[Geert Uytterhoeven]

Hi Bj=C3=B6rn,

On Mon, Mar 20, 2017 at 7:42 PM, Bjorn Helgaas <bhelgaas@google.com> wrote:
> Several arches use __ioremap() to help implement the generic ioremap(),
> ioremap_nocache(), and ioremap_wc() interfaces, but this usage is all
> inside the arch/ directory.
>
> The only __ioremap() uses outside arch/ are in the ZorroII RAM disk drive=
r
> and some framebuffer drivers that are only buildable on m68k and powerpc,
> and they use the versions provided by those arches.
>
> There's no need for a generic version of __ioremap(), so remove it.

These all predate the ioremap_*() variants, and can be converted to
either ioremap_nocache() or ioremap_wt().

However, PPC doesn't implement ioremap_wt() yet, so asm-generic will
fall back to the less-efficient nocache variant.
PPC does support __ioremap(..., _PAGE_WRITETHRU), so adding a wrapper
is trivial.

> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
> Reviewed-by: Arnd Bergmann <arnd@arndb.de>

Regardless,
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

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. Bu=
t
when I'm talking to journalists I just say "programmer" or something like t=
hat.
                                -- Linus Torvalds

Re: [PATCH v2 2/4] asm-generic/io.h: Remove unused generic __ioremap() definition

[Bjorn Helgaas]

On Tue, Mar 21, 2017 at 11:37:11AM +0100, Geert Uytterhoeven wrote:
> Hi Björn,
> 
> On Mon, Mar 20, 2017 at 7:42 PM, Bjorn Helgaas <bhelgaas@google.com> wrote:
> > Several arches use __ioremap() to help implement the generic ioremap(),
> > ioremap_nocache(), and ioremap_wc() interfaces, but this usage is all
> > inside the arch/ directory.
> >
> > The only __ioremap() uses outside arch/ are in the ZorroII RAM disk driver
> > and some framebuffer drivers that are only buildable on m68k and powerpc,
> > and they use the versions provided by those arches.
> >
> > There's no need for a generic version of __ioremap(), so remove it.
> 
> These all predate the ioremap_*() variants, and can be converted to
> either ioremap_nocache() or ioremap_wt().
> 
> However, PPC doesn't implement ioremap_wt() yet, so asm-generic will
> fall back to the less-efficient nocache variant.
> PPC does support __ioremap(..., _PAGE_WRITETHRU), so adding a wrapper
> is trivial.

Thanks, I'll try adding ioremap_wt() (at least for PPC32) and cleaning this
up.

> > Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
> > Reviewed-by: Arnd Bergmann <arnd@arndb.de>
> 
> Regardless,
> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
> 
> 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