[Intel-gfx] [PATCH 2/2] drm/i915: Reset the gpu on takeover

[Joonas Lahtinen]

On la, 2017-01-21 at 14:50 +0000, Chris Wilson wrote:
> The GPU may be in an unknown state following resume and module load. The
> previous occupant may have left contexts loaded, or other dangerous
> state, which can cause an immediate GPU hang for us. The only save
> course of action is to reset the GPU prior to using it - similarly to
> how we reset the GPU prior to unload (before a second user may be
> affected by our leftover state).
> 
> We need to reset the GPU very early in our load/resume sequence so that
> any stale HW pointers are revoked prior to any resource allocations we
> make (that may conflict).
> 
> A reset should only be a couple of milliseconds on a slow device, a cost
> we should easily be able to absorb into our initialisation times.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

Can't really suggest better names for the functions, so;

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

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