Problem with dma_alloc_coherent at linux-2.6.33-arm1 , with RealView platform,board PBX-A9 and armv7 instructions.

[David Yang]

Ok,I see .

I will try the patch you offered.

And I will give the results later.

Thanks!

On Thu, Jul 15, 2010 at 5:59 PM, Russell King - ARM Linux
<linux at arm.linux.org.uk> wrote:
> On Thu, Jul 15, 2010 at 05:56:41PM +0800, David Yang wrote:
>> I have explicitly added the barrier() in my driver, but it did't work.
>
> This imples that you've tried your own solution, which is completely
> different from Catalin's patches.
>
> barrier() is just a compiler barrier, nothing more.  It won't have any
> effect on external memory ordering.  It's not surprising this doesn't
> have much effect.
>