Re: [PATCH] fb.h: ARM uses __raw_{read/write}

[Arnd Bergmann]

On Monday 13 June 2011 12:08:19 Catalin Marinas wrote:
> The change proposed by Hartley wouldn't make much difference from the
> current volatile accesses (__raw_* accessors are implemented as volatile
> on ARM).

I guess it would mainly make a difference if we get a platform where
the PCI bus window is not in the same address space as the regular
physical memory and the accessors actually need to do a computation
on the address. AFAICT, ARM does not currently have any such platform
and I would hope that it says that way.

> I think the memcpy_(from|to)io could be optimised on ARM to only add a
> barrier before or after he copying loop.

Agreed, good idea.

	Arnd
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/