[PATCH 5/8] drm/panthor: Minor scheduler refactoring

[Ketil Johnsen <ketil.johnsen@arm.com>]

From: Florent Tomasin <florent.tomasin@arm.com>

Refactor parts of the group scheduling logic into new helper functions.
This will simplify addition of the protected mode feature.

Remove redundant assignments of csg_slot.

Signed-off-by: Florent Tomasin <florent.tomasin@arm.com>
Co-developed-by: Ketil Johnsen <ketil.johnsen@arm.com>
Signed-off-by: Ketil Johnsen <ketil.johnsen@arm.com>
---
 drivers/gpu/drm/panthor/panthor_sched.c | 135 +++++++++++++++---------
 1 file changed, 86 insertions(+), 49 deletions(-)

diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
index 5ee386338005c..987072bd867c4 100644
--- a/drivers/gpu/drm/panthor/panthor_sched.c
+++ b/drivers/gpu/drm/panthor/panthor_sched.c
@@ -1934,6 +1934,12 @@ static void csgs_upd_ctx_init(struct panthor_csg_slots_upd_ctx *ctx)
 	memset(ctx, 0, sizeof(*ctx));
 }
 
+static void csgs_upd_ctx_ring_doorbell(struct panthor_csg_slots_upd_ctx *ctx,
+				       u32 csg_id)
+{
+	ctx->update_mask |= BIT(csg_id);
+}
+
 static void csgs_upd_ctx_queue_reqs(struct panthor_device *ptdev,
 				    struct panthor_csg_slots_upd_ctx *ctx,
 				    u32 csg_id, u32 value, u32 mask)
@@ -1944,7 +1950,8 @@ static void csgs_upd_ctx_queue_reqs(struct panthor_device *ptdev,
 
 	ctx->requests[csg_id].value = (ctx->requests[csg_id].value & ~mask) | (value & mask);
 	ctx->requests[csg_id].mask |= mask;
-	ctx->update_mask |= BIT(csg_id);
+
+	csgs_upd_ctx_ring_doorbell(ctx, csg_id);
 }
 
 static int csgs_upd_ctx_apply_locked(struct panthor_device *ptdev,
@@ -1961,8 +1968,12 @@ static int csgs_upd_ctx_apply_locked(struct panthor_device *ptdev,
 	while (update_slots) {
 		struct panthor_fw_csg_iface *csg_iface;
 		u32 csg_id = ffs(update_slots) - 1;
+		u32 req_mask = ctx->requests[csg_id].mask;
 
 		update_slots &= ~BIT(csg_id);
+		if (!req_mask)
+			continue;
+
 		csg_iface = panthor_fw_get_csg_iface(ptdev, csg_id);
 		panthor_fw_update_reqs(csg_iface, req,
 				       ctx->requests[csg_id].value,
@@ -1979,6 +1990,9 @@ static int csgs_upd_ctx_apply_locked(struct panthor_device *ptdev,
 		int ret;
 
 		update_slots &= ~BIT(csg_id);
+		if (!req_mask)
+			continue;
+
 		csg_iface = panthor_fw_get_csg_iface(ptdev, csg_id);
 
 		ret = panthor_fw_csg_wait_acks(ptdev, csg_id, req_mask, &acked, 100);
@@ -2266,12 +2280,76 @@ tick_ctx_cleanup(struct panthor_scheduler *sched,
 	}
 }
 
+static void
+tick_ctx_evict_group(struct panthor_scheduler *sched,
+		     struct panthor_csg_slots_upd_ctx *upd_ctx,
+		     struct panthor_group *group)
+{
+	struct panthor_device *ptdev = sched->ptdev;
+
+	if (drm_WARN_ON(&ptdev->base, group->csg_id < 0))
+		return;
+
+	csgs_upd_ctx_queue_reqs(ptdev, upd_ctx, group->csg_id,
+				group_can_run(group) ?
+				CSG_STATE_SUSPEND : CSG_STATE_TERMINATE,
+				CSG_STATE_MASK);
+}
+
+
+static void
+tick_ctx_reschedule_group(struct panthor_scheduler *sched,
+			  struct panthor_csg_slots_upd_ctx *upd_ctx,
+			  struct panthor_group *group,
+			  int new_csg_prio)
+{
+	struct panthor_device *ptdev = sched->ptdev;
+	struct panthor_fw_csg_iface *csg_iface;
+	struct panthor_csg_slot *csg_slot;
+
+	if (group->csg_id < 0)
+		return;
+
+	csg_iface = panthor_fw_get_csg_iface(ptdev, group->csg_id);
+	csg_slot = &sched->csg_slots[group->csg_id];
+
+	if (csg_slot->priority != new_csg_prio) {
+		panthor_fw_update_reqs(csg_iface, endpoint_req,
+				       CSG_EP_REQ_PRIORITY(new_csg_prio),
+				       CSG_EP_REQ_PRIORITY_MASK);
+		csgs_upd_ctx_queue_reqs(ptdev, upd_ctx, group->csg_id,
+					csg_iface->output->ack ^ CSG_ENDPOINT_CONFIG,
+					CSG_ENDPOINT_CONFIG);
+	}
+}
+
+static void
+tick_ctx_schedule_group(struct panthor_scheduler *sched,
+			struct panthor_sched_tick_ctx *ctx,
+			struct panthor_csg_slots_upd_ctx *upd_ctx,
+			struct panthor_group *group,
+			int csg_id, int csg_prio)
+{
+	struct panthor_device *ptdev = sched->ptdev;
+	struct panthor_fw_csg_iface *csg_iface = panthor_fw_get_csg_iface(ptdev, csg_id);
+
+	group_bind_locked(group, csg_id);
+	csg_slot_prog_locked(ptdev, csg_id, csg_prio);
+
+	csgs_upd_ctx_queue_reqs(ptdev, upd_ctx, csg_id,
+				group->state == PANTHOR_CS_GROUP_SUSPENDED ?
+				CSG_STATE_RESUME : CSG_STATE_START,
+				CSG_STATE_MASK);
+	csgs_upd_ctx_queue_reqs(ptdev, upd_ctx, csg_id,
+				csg_iface->output->ack ^ CSG_ENDPOINT_CONFIG,
+				CSG_ENDPOINT_CONFIG);
+}
+
 static void
 tick_ctx_apply(struct panthor_scheduler *sched, struct panthor_sched_tick_ctx *ctx)
 {
 	struct panthor_group *group, *tmp;
 	struct panthor_device *ptdev = sched->ptdev;
-	struct panthor_csg_slot *csg_slot;
 	int prio, new_csg_prio = MAX_CSG_PRIO, i;
 	u32 free_csg_slots = 0;
 	struct panthor_csg_slots_upd_ctx upd_ctx;
@@ -2282,42 +2360,12 @@ tick_ctx_apply(struct panthor_scheduler *sched, struct panthor_sched_tick_ctx *c
 	for (prio = PANTHOR_CSG_PRIORITY_COUNT - 1; prio >= 0; prio--) {
 		/* Suspend or terminate evicted groups. */
 		list_for_each_entry(group, &ctx->old_groups[prio], run_node) {
-			bool term = !group_can_run(group);
-			int csg_id = group->csg_id;
-
-			if (drm_WARN_ON(&ptdev->base, csg_id < 0))
-				continue;
-
-			csg_slot = &sched->csg_slots[csg_id];
-			csgs_upd_ctx_queue_reqs(ptdev, &upd_ctx, csg_id,
-						term ? CSG_STATE_TERMINATE : CSG_STATE_SUSPEND,
-						CSG_STATE_MASK);
+			tick_ctx_evict_group(sched, &upd_ctx, group);
 		}
 
 		/* Update priorities on already running groups. */
 		list_for_each_entry(group, &ctx->groups[prio], run_node) {
-			struct panthor_fw_csg_iface *csg_iface;
-			int csg_id = group->csg_id;
-
-			if (csg_id < 0) {
-				new_csg_prio--;
-				continue;
-			}
-
-			csg_slot = &sched->csg_slots[csg_id];
-			csg_iface = panthor_fw_get_csg_iface(ptdev, csg_id);
-			if (csg_slot->priority == new_csg_prio) {
-				new_csg_prio--;
-				continue;
-			}
-
-			panthor_fw_csg_endpoint_req_update(ptdev, csg_iface,
-							   CSG_EP_REQ_PRIORITY(new_csg_prio),
-							   CSG_EP_REQ_PRIORITY_MASK);
-			csgs_upd_ctx_queue_reqs(ptdev, &upd_ctx, csg_id,
-						csg_iface->output->ack ^ CSG_ENDPOINT_CONFIG,
-						CSG_ENDPOINT_CONFIG);
-			new_csg_prio--;
+			tick_ctx_reschedule_group(sched, &upd_ctx, group, new_csg_prio--);
 		}
 	}
 
@@ -2354,28 +2402,17 @@ tick_ctx_apply(struct panthor_scheduler *sched, struct panthor_sched_tick_ctx *c
 	for (prio = PANTHOR_CSG_PRIORITY_COUNT - 1; prio >= 0; prio--) {
 		list_for_each_entry(group, &ctx->groups[prio], run_node) {
 			int csg_id = group->csg_id;
-			struct panthor_fw_csg_iface *csg_iface;
+			int csg_prio = new_csg_prio--;
 
-			if (csg_id >= 0) {
-				new_csg_prio--;
+			if (csg_id >= 0)
 				continue;
-			}
 
 			csg_id = ffs(free_csg_slots) - 1;
 			if (drm_WARN_ON(&ptdev->base, csg_id < 0))
 				break;
 
-			csg_iface = panthor_fw_get_csg_iface(ptdev, csg_id);
-			csg_slot = &sched->csg_slots[csg_id];
-			group_bind_locked(group, csg_id);
-			csg_slot_prog_locked(ptdev, csg_id, new_csg_prio--);
-			csgs_upd_ctx_queue_reqs(ptdev, &upd_ctx, csg_id,
-						group->state == PANTHOR_CS_GROUP_SUSPENDED ?
-						CSG_STATE_RESUME : CSG_STATE_START,
-						CSG_STATE_MASK);
-			csgs_upd_ctx_queue_reqs(ptdev, &upd_ctx, csg_id,
-						csg_iface->output->ack ^ CSG_ENDPOINT_CONFIG,
-						CSG_ENDPOINT_CONFIG);
+			tick_ctx_schedule_group(sched, ctx, &upd_ctx, group, csg_id, csg_prio);
+
 			free_csg_slots &= ~BIT(csg_id);
 		}
 	}
-- 
2.43.0