[Intel-gfx] [PATCH] drm/i915: Always wake the device to flush the GTT

[Joonas Lahtinen]

On Tue, 2017-08-29 at 11:33 +0100, Chris Wilson wrote:
> Since we hold the device wakeref when writing through the GTT (otherwise
> the writes would fail), we presumed that before the device sleeps those
> writes would naturally be flushed and that we wouldn't need our mmio
> read trick. However, that presumption seems false and a sleepy bxt seems
> to require us to always manually flush the GTT writes prior to direct
> access.
> 
> Fixes: e2a2aa36a509 ("drm/i915: Check we have an wake device before flushing GTT writes")
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>

Got any Bugzilla, Testcase, Tested-by?

Does what the message describes.

Reviewed-by: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>

Regards, Joonas
-- 
Joonas Lahtinen
Open Source Technology Center
Intel Corporation