[PATCH v4 3/4] arch/*/io.h: remove ioremap_uc in some architectures

Michael Ellerman mpe at ellerman.id.au
Fri Mar 10 09:54:27 AEDT 2023


Baoquan He <bhe at redhat.com> writes:
> ioremap_uc() is only meaningful on old x86-32 systems with the PAT
> extension, and on ia64 with its slightly unconventional ioremap()
> behavior. So remove the ioremap_uc() definition in architecutures
> other than x86 and ia64. These architectures all have asm-generic/io.h
> included and will have the default ioremap_uc() definition which
> returns NULL.
>
> This changes the existing behaviour, while no need to worry about
> any breakage because in the only callsite of ioremap_uc(), code
> has been adjusted to eliminate the impact. Please see
> atyfb_setup_generic() of drivers/video/fbdev/aty/atyfb_base.c.
>
> If any new invocation of ioremap_uc() need be added, please consider
> using ioremap() intead or adding a ARCH specific version if necessary.
>
> Acked-by: Geert Uytterhoeven <geert at linux-m68k.org>
> Signed-off-by: Baoquan He <bhe at redhat.com>
> Cc: linux-alpha at vger.kernel.org
> Cc: linux-hexagon at vger.kernel.org
> Cc: linux-m68k at lists.linux-m68k.org
> Cc: linux-mips at vger.kernel.org
> Cc: linux-parisc at vger.kernel.org
> Cc: linuxppc-dev at lists.ozlabs.org
> Cc: linux-sh at vger.kernel.org
> Cc: sparclinux at vger.kernel.org
> ---
>  Documentation/driver-api/device-io.rst | 9 +++++----
>  arch/alpha/include/asm/io.h            | 1 -
>  arch/hexagon/include/asm/io.h          | 3 ---
>  arch/m68k/include/asm/kmap.h           | 1 -
>  arch/mips/include/asm/io.h             | 1 -
>  arch/parisc/include/asm/io.h           | 2 --
>  arch/powerpc/include/asm/io.h          | 1 -

Acked-by: Michael Ellerman <mpe at ellerman.id.au> (powerpc)

cheers


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