ntb_hw_switchtec: Remove redundant steps of switchtec_ntb_reinit_peer() function

When a re-initialization is caused by a link event, the driver will
re-setup the shared memory window. But at that time, the shared memory
is still valid, and it's unnecessary to free, reallocate and then
initialize it again. We only need to reconfigure the hardware
registers. Remove the redundant steps from
switchtec_ntb_reinit_peer() function.

Signed-off-by: Joey Zhang <joey.zhang@microchip.com>
Signed-off-by: Wesley Sheng <wesley.sheng@microchip.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
diff --git a/drivers/ntb/hw/mscc/ntb_hw_switchtec.c b/drivers/ntb/hw/mscc/ntb_hw_switchtec.c
index 26a8873..c408b7a 100644
--- a/drivers/ntb/hw/mscc/ntb_hw_switchtec.c
+++ b/drivers/ntb/hw/mscc/ntb_hw_switchtec.c
@@ -1457,10 +1457,13 @@
 
 static int switchtec_ntb_reinit_peer(struct switchtec_ntb *sndev)
 {
-	dev_info(&sndev->stdev->dev, "peer reinitialized\n");
-	switchtec_ntb_deinit_shared_mw(sndev);
-	switchtec_ntb_init_mw(sndev);
-	return switchtec_ntb_init_shared_mw(sndev);
+	int rc;
+
+	dev_info(&sndev->stdev->dev, "reinitialize shared memory window\n");
+	rc = config_rsvd_lut_win(sndev, sndev->mmio_peer_ctrl, 0,
+				 sndev->self_partition,
+				 sndev->self_shared_dma);
+	return rc;
 }
 
 static int switchtec_ntb_add(struct device *dev,