gpu: nvgpu: fix event id polling

In gk20a_event_id_poll(), we always set the mask value
and return it. This causes poll() from UMD to be always
successful irrespective of event is really generated or not

Fix this by adding a flag event_posted for each event
Set this flag while posting the event
In gk20a_event_id_poll(), set the mask value only if
this flag is set. If flag is set, set mask and clear the flag

Bug 200089620

Change-Id: If14236547c611fe4bfa1410ff5b69c9fa02d43bb
Signed-off-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-on: http://git-master/r/1160253
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/tsg_gk20a.c b/drivers/gpu/nvgpu/gk20a/tsg_gk20a.c
index 5298d380..f7d5535d 100644
--- a/drivers/gpu/nvgpu/gk20a/tsg_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/tsg_gk20a.c
@@ -231,6 +231,7 @@ void gk20a_tsg_event_id_post_event(struct tsg_gk20a *tsg,
         gk20a_dbg_info(
                 "posting event for event_id=%d on tsg=%d\n",
                 event_id, tsg->tsgid);
+        event_id_data->event_posted = true;
 
         wake_up_interruptible_all(&event_id_data->event_id_wq);