net: hns3: After setting the loopback, add the status of getting MAC

After setting the serdes loopback, you need to determine
the status of the MAC negotiation. If a status exception
is obtained after 200ms, a timeout error is returned.
Signed-off-by: liuzhongzhu <liuzhongzhu@huawei.com>
Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c

@@ -5237,8 +5237,15 @@ static int hclge_set_serdes_loopback(struct hclge_dev *hdev, bool en,
 {
 #define HCLGE_SERDES_RETRY_MS	10
 #define HCLGE_SERDES_RETRY_NUM	100
+
+#define HCLGE_MAC_LINK_STATUS_MS   20
+#define HCLGE_MAC_LINK_STATUS_NUM  10
+#define HCLGE_MAC_LINK_STATUS_DOWN 0
+#define HCLGE_MAC_LINK_STATUS_UP   1
+
 	struct hclge_serdes_lb_cmd *req;
 	struct hclge_desc desc;
+	int mac_link_ret = 0;
 	int ret, i = 0;
 	u8 loop_mode_b;
 
@@ -5261,8 +5268,10 @@ static int hclge_set_serdes_loopback(struct hclge_dev *hdev, bool en,
 	if (en) {
 		req->enable = loop_mode_b;
 		req->mask = loop_mode_b;
+		mac_link_ret = HCLGE_MAC_LINK_STATUS_UP;
 	} else {
 		req->mask = loop_mode_b;
+		mac_link_ret = HCLGE_MAC_LINK_STATUS_DOWN;
 	}
 
 	ret = hclge_cmd_send(&hdev->hw, &desc, 1);
@@ -5294,7 +5303,19 @@ static int hclge_set_serdes_loopback(struct hclge_dev *hdev, bool en,
 	}
 
 	hclge_cfg_mac_mode(hdev, en);
-	return 0;
+
+	i = 0;
+	do {
+		/* serdes Internal loopback, independent of the network cable.*/
+		msleep(HCLGE_MAC_LINK_STATUS_MS);
+		ret = hclge_get_mac_link_status(hdev);
+		if (ret == mac_link_ret)
+			return 0;
+	} while (++i < HCLGE_MAC_LINK_STATUS_NUM);
+
+	dev_err(&hdev->pdev->dev, "config mac mode timeout\n");
+
+	return -EBUSY;
 }
 
 static int hclge_tqp_enable(struct hclge_dev *hdev, int tqp_id,