[PATCH 14/14] arm/include/asm/io.h : added macros to read/write big/little endian register

Benjamin Herrenschmidt benh at kernel.crashing.org
Tue Sep 6 03:16:59 EST 2011

On Mon, 2011-09-05 at 16:28 +0200, Sebastian Andrzej Siewior wrote:
> * Benjamin Herrenschmidt | 2011-09-02 21:01:43 [+1000]:
> >or better, switch to the newer iomap variants which should be
> >provided in both endianness.
> I know some ppc-mmu provide the capability to perform the endian swap
> during page access. I wasn't aware that there is a kernel wide interface
> for this. What do you do on architectures which don't provide this?

Oh we don't provide a kernel interface for it, well not "officially",
that's not what I meant by using iomap.

You -can- use the platform specific _PAGE_ENDIAN to ioremap_flags() but
that's very platform specific and it's up to you to know you're doing it
on a CPU that supports it :-)


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