drm/panthor: Reset queue slots if termination fails

Make sure the queue slot is reset even if we failed termination so
we don't have garbage in the CS input interface after a reset. In
practice that's not a problem because we zero out all RW sections when
a hangs occurs, but it's safer to reset things manually, in case we
decide to not conditionally reload RW sections based on the type of
hang.

v4:
- Split the changes in two separate patches

v5:
- No changes

v6:
- Adjust the explanation in the commit message
- Drop the Fixes tag
- Put after the timeout changes and make the two patches independent
  so one can be backported, and the other not

v7:
- Use the local group variable instead of dereferencing csg_slot->group
- Add Steve's R-b

v8:
- No changes

Signed-off-by: Ashley Smith <ashley.smith@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patch.msgid.link/20251113105734.1520338-3-boris.brezillon@collabora.com
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>

1 files changed, 12 insertions, 2 deletions

diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
index 6fb3208efc05..b834123a6560 100644
--- a/drivers/gpu/drm/panthor/panthor_sched.c
+++ b/drivers/gpu/drm/panthor/panthor_sched.c
@@ -2841,13 +2841,23 @@ void panthor_sched_suspend(struct panthor_device *ptdev)
 		while (slot_mask) {
 			u32 csg_id = ffs(slot_mask) - 1;
 			struct panthor_csg_slot *csg_slot = &sched->csg_slots[csg_id];
+			struct panthor_group *group = csg_slot->group;
 
 			/* Terminate command timedout, but the soft-reset will
 			 * automatically terminate all active groups, so let's
 			 * force the state to halted here.
 			 */
-			if (csg_slot->group->state != PANTHOR_CS_GROUP_TERMINATED)
-				csg_slot->group->state = PANTHOR_CS_GROUP_TERMINATED;
+			if (group->state != PANTHOR_CS_GROUP_TERMINATED) {
+				group->state = PANTHOR_CS_GROUP_TERMINATED;
+
+				/* Reset the queue slots manually if the termination
+				 * request failed.
+				 */
+				for (i = 0; i < group->queue_count; i++) {
+					if (group->queues[i])
+						cs_slot_reset_locked(ptdev, csg_id, i);
+				}
+			}
 			slot_mask &= ~BIT(csg_id);
 		}
 	}