drm/i915: Reset the HEAD pointer for the ring after writing START

Ville found an old w/a documented for g4x that suggested that we need to
reset the HEAD after writing START. This is a useful fixup for some of
the g4x ring initialisation woes, but as usual, not all.

v2: Do the rewrite unconditionally anyway

References: https://bugs.freedesktop.org/show_bug.cgi?id=76554
Signed-off-by: Chris Wilson <[email protected]>
Cc: Ville Syrjälä <[email protected]>
Reviewed-by: Ville Syrjälä <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>

0 files changed, 0 insertions, 0 deletions