gma: Always clear hot-plug events before enabling a pipe

For cold plugging, we don't wait for a hot-plug event. But, even if we
are not supposed to wait for a hot-plug event, we have to clear any
pending event. Also, a failed DP training can result in another hot-plug
event.

A stale event would be spuriously interpreted as a disconnect, resul-
ting in an infinite loop of cycling the pipe on and off.

Change-Id: I4c7bbe0ac792553c94e928ba0a5eeb822a857f9c
Signed-off-by: Nico Huber <nico.huber@secunet.com>
Reviewed-on: https://review.coreboot.org/18122
Tested-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
4 files changed
tree: cc43f9a129c898a5735219f6ba6e65240dc2f62b
  1. common/
  2. configs/
  3. .gitignore
  4. COPYING
  5. Makefile
  6. Makefile.inc
  7. TODO