tree 86d17ba0c90eed7347f2a136c44a821b42c5798d
parent be26a10bd10271b4a810ece2e540c0cdd77881bc
author Jesse Barnes <jbarnes@virtuousgeek.org> 1270501431 -0700
committer Eric Anholt <eric@anholt.net> 1276909188 -0700

drm/i915: don't queue flips during a flip pending event

Hardware will set the flip pending ISR bit as soon as it receives the
flip instruction, and (supposedly) clear it once the flip completes
(e.g. at the next vblank).  If we try to send down a flip instruction
while the ISR bit is set, the hardware can become very confused, and we
may never receive the corresponding flip pending interrupt, effectively
hanging the chip.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>