[PATCH 1/1] drm/xe: Build PM into GuC CT layer

[Matthew Brost]

Take PM ref when a G2H is outstanding, drop when it is received.

To safely ensure we have PM ref when in the GuC CT layer, a PM ref needs
to be held when scheduler messages are pending too.

Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
Cc: Nirmoy Das <nirmoy.das at intel.com>
Signed-off-by: Matthew Brost <matthew.brost at intel.com>
---
 drivers/gpu/drm/xe/xe_guc_ct.c     | 5 +++++
 drivers/gpu/drm/xe/xe_guc_submit.c | 4 ++++
 2 files changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_guc_ct.c b/drivers/gpu/drm/xe/xe_guc_ct.c
index 7d2e937da1d8..560f7e4bf290 100644
--- a/drivers/gpu/drm/xe/xe_guc_ct.c
+++ b/drivers/gpu/drm/xe/xe_guc_ct.c
@@ -327,6 +327,8 @@ static void xe_guc_ct_set_state(struct xe_guc_ct *ct,
 	xe_gt_assert(ct_to_gt(ct), ct->g2h_outstanding == 0 ||
 		     state == XE_GUC_CT_STATE_STOPPED);
 
+	while (ct->g2h_outstanding--)
+		xe_pm_runtime_put(ct_to_xe(ct));
 	ct->g2h_outstanding = 0;
 	ct->state = state;
 
@@ -501,6 +503,8 @@ static void __g2h_reserve_space(struct xe_guc_ct *ct, u32 g2h_len, u32 num_g2h)
 
 		ct->ctbs.g2h.info.space -= g2h_len;
 		ct->g2h_outstanding += num_g2h;
+		while (num_g2h--)
+			xe_pm_runtime_get_noresume(ct_to_xe(ct));
 	}
 }
 
@@ -512,6 +516,7 @@ static void __g2h_release_space(struct xe_guc_ct *ct, u32 g2h_len)
 
 	ct->ctbs.g2h.info.space += g2h_len;
 	--ct->g2h_outstanding;
+	xe_pm_runtime_put(ct_to_xe(ct));
 }
 
 static void g2h_release_space(struct xe_guc_ct *ct, u32 g2h_len)
diff --git a/drivers/gpu/drm/xe/xe_guc_submit.c b/drivers/gpu/drm/xe/xe_guc_submit.c
index 860405527115..993d0344dc88 100644
--- a/drivers/gpu/drm/xe/xe_guc_submit.c
+++ b/drivers/gpu/drm/xe/xe_guc_submit.c
@@ -1402,6 +1402,8 @@ static void guc_exec_queue_process_msg(struct xe_sched_msg *msg)
 	default:
 		XE_WARN_ON("Unknown message type");
 	}
+
+	xe_pm_runtime_put(guc_to_xe(exec_queue_to_guc(msg->private_data)));
 }
 
 static const struct drm_sched_backend_ops drm_sched_ops = {
@@ -1492,6 +1494,8 @@ static void guc_exec_queue_kill(struct xe_exec_queue *q)
 static void guc_exec_queue_add_msg(struct xe_exec_queue *q, struct xe_sched_msg *msg,
 				   u32 opcode)
 {
+	xe_pm_runtime_get_noresume(guc_to_xe(exec_queue_to_guc(q)));
+
 	INIT_LIST_HEAD(&msg->link);
 	msg->opcode = opcode;
 	msg->private_data = q;
-- 
2.34.1