msm: camera: reqmgr: Verify the req of two links

The req of two links should be same if current
frame sync with previous frame of sync link, CRM can
do self-correction based on this condition.

CRs-Fixed: 2492019
Change-Id: Idb208958a850ec1fe12f12443e7ecc2e126970d8
Signed-off-by: Depeng Shao <[email protected]>

drivers/cam_req_mgr/cam_req_mgr_core.c

@@ -995,7 +995,8 @@ static int __cam_req_mgr_check_sync_req_is_ready(
 	struct cam_req_mgr_slot *slot)
 {
 	struct cam_req_mgr_core_link *sync_link = NULL;
-	int64_t req_id = 0;
+	struct cam_req_mgr_slot *sync_rd_slot = NULL;
+	int64_t req_id = 0, sync_req_id = 0;
 	int sync_slot_idx = 0, sync_rd_idx = 0, rc = 0;
 	int32_t sync_num_slots = 0;
 	uint64_t sync_frame_duration = 0;
@@ -1009,6 +1010,9 @@ static int __cam_req_mgr_check_sync_req_is_ready(
 	sync_link = link->sync_link;
 	req_id = slot->req_id;
 	sync_num_slots = sync_link->req.in_q->num_slots;
+	sync_rd_idx = sync_link->req.in_q->rd_idx;
+	sync_rd_slot = &sync_link->req.in_q->slot[sync_rd_idx];
+	sync_req_id = sync_rd_slot->req_id;
 
 	CAM_DBG(CAM_REQ,
 		"link_hdl %x req %lld frame_skip_flag %d ",
@@ -1091,12 +1095,11 @@ static int __cam_req_mgr_check_sync_req_is_ready(
 		return -EAGAIN;
 	}
 
-	sync_rd_idx = sync_link->req.in_q->rd_idx;
 	if ((sync_link->req.in_q->slot[sync_slot_idx].status !=
 		CRM_SLOT_STATUS_REQ_APPLIED) &&
 		(((sync_slot_idx - sync_rd_idx + sync_num_slots) %
 		sync_num_slots) >= 1) &&
-		(sync_link->req.in_q->slot[sync_rd_idx].status !=
+		(sync_rd_slot->status !=
 		CRM_SLOT_STATUS_REQ_APPLIED)) {
 		CAM_DBG(CAM_CRM,
 			"Req: %lld [other link] not next req to be applied on link: %x",
@@ -1129,7 +1132,14 @@ static int __cam_req_mgr_check_sync_req_is_ready(
 		CAM_DBG(CAM_CRM,
 			"Req: %lld ready %d sync_ready %d, ignore sync link next SOF",
 			req_id, ready, sync_ready);
-		link->sync_link_sof_skip = true;
+
+		/*
+		 * Only skip the frames if current frame sync with
+		 * next frame of sync link.
+		 */
+		if (link->sof_timestamp - sync_link->sof_timestamp >
+			sync_frame_duration / 2)
+			link->sync_link_sof_skip = true;
 		return -EINVAL;
 	} else if (ready == false) {
 		CAM_DBG(CAM_CRM,
@@ -1138,6 +1148,41 @@ static int __cam_req_mgr_check_sync_req_is_ready(
 		return -EINVAL;
 	}
 
+	/*
+	 * Do the self-correction when the frames are sync,
+	 * we consider that the frames are synced if the
+	 * difference of two SOF timestamp less than
+	 * (sync_frame_duration / 5).
+	 */
+	if ((link->sof_timestamp > sync_link->sof_timestamp) &&
+		(sync_link->sof_timestamp > 0) &&
+		(link->sof_timestamp - sync_link->sof_timestamp <
+		sync_frame_duration / 5) &&
+		(sync_rd_slot->sync_mode == CAM_REQ_MGR_SYNC_MODE_SYNC)) {
+
+		/*
+		 * This means current frame should sync with next
+		 * frame of sync link, then the request id of in
+		 * rd slot of two links should be same.
+		 */
+		CAM_DBG(CAM_CRM,
+			"link %x req_id %lld, sync_link %x req_id %lld",
+			link->link_hdl, req_id,
+			sync_link->link_hdl, sync_req_id);
+
+		if (req_id > sync_req_id) {
+			CAM_DBG(CAM_CRM,
+				"link %x too quickly, skip this frame",
+				link->link_hdl);
+			return -EAGAIN;
+		} else if (req_id < sync_req_id) {
+			CAM_DBG(CAM_CRM,
+				"sync link %x too quickly, skip next frame of sync link",
+				sync_link->link_hdl);
+			link->sync_link_sof_skip = true;
+		}
+	}
+
 	CAM_DBG(CAM_REQ,
 		"Req: %lld ready to apply on link: %x [validation successful]",
 		req_id, link->link_hdl);