drm/i915/gt: Add delay to let engine resumes properly

Sometimes engine reset fails because the engine resumes from an
incorrect RING_HEAD. Engine head failed to set to zero even after
writing into it. This is a timing issue and we experimented
different values and found out that 20ms delay works best based
on testing.

So, add a 20ms delay to let engine resumes from correct RING_HEAD.

Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/13968
Signed-off-by: Nitin Gote <[email protected]>
Reviewed-by: Sebastian Brzezinka <[email protected]>
Reviewed-by: Krzysztof Karas <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rodrigo Vivi <[email protected]>

0 files changed, 0 insertions, 0 deletions