r600_dma_ring_test() failed - synchronization problem with write-combining memory

[Alexander Fyodorov]

13.10.2014, 21:50, "Alex Deucher" <alexdeucher at gmail.com>:
> On Fri, Oct 10, 2014 at 12:00 PM, Alex Deucher <alexdeucher at gmail.com> wrote:
>>  I think I'd prefer to just switch the test to use gart memory since
>>  this code is shared by different asics thay may not all implement hdp
>>  flush the same way.  We can just reserve a couple of slots in the wb
>>  page.
>
> Does the attached patch work for you as well?

Yes, although it became a little bit slower - it now completes in 2 usecs.