[Intel-gfx] [PATCH] drm/i915: Click the ACTHD three times to go home

[Mika Kuoppala]

Chris Wilson <chris at chris-wilson.co.uk> writes:

> On Mon, Mar 27, 2017 at 01:12:30PM +0300, Mika Kuoppala wrote:
>> Chris Wilson <chris at chris-wilson.co.uk> writes:
>> 
>> > One POSTING_READ of ACTHD may not be enough to ensure that the seqno
>> > write has been posted from the GPU and is now visible. So do three!
>> >
>> 
>> Is this about posting read triggering or just adding enough delay
>> that the write gets through?
>
> It's purely about a delay that we guess will cover 99.9999% of cases.

Acked-by: Mika Kuoppala <mika.kuoppala at intel.com>

> -Chris
>
> -- 
> Chris Wilson, Intel Open Source Technology Centre