net: hns3: add wait until mac link down

In some configure flow of hns3 driver, for example, change mtu, it will
disable MAC through firmware before configuration. But firmware disables
MAC asynchronously. The rx traffic may be not stopped in this case.

So fixes it by waiting until mac link is down.

Fixes: a9775bb6 ("net: hns3: fix set and get link ksettings issue")
Signed-off-by: Jie Wang <wangjie125@huawei.com>
Signed-off-by: Jijie Shao <shaojijie@huawei.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20230807113452.474224-4-shaojijie@huawei.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

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

@@ -7560,6 +7560,8 @@ static void hclge_enable_fd(struct hnae3_handle *handle, bool enable)
 
 static void hclge_cfg_mac_mode(struct hclge_dev *hdev, bool enable)
 {
+#define HCLGE_LINK_STATUS_WAIT_CNT  3
+
 	struct hclge_desc desc;
 	struct hclge_config_mac_mode_cmd *req =
 		(struct hclge_config_mac_mode_cmd *)desc.data;
@@ -7584,9 +7586,15 @@ static void hclge_cfg_mac_mode(struct hclge_dev *hdev, bool enable)
 	req->txrx_pad_fcs_loop_en = cpu_to_le32(loop_en);
 
 	ret = hclge_cmd_send(&hdev->hw, &desc, 1);
-	if (ret)
+	if (ret) {
 		dev_err(&hdev->pdev->dev,
 			"mac enable fail, ret =%d.\n", ret);
+		return;
+	}
+
+	if (!enable)
+		hclge_mac_link_status_wait(hdev, HCLGE_LINK_STATUS_DOWN,
+					   HCLGE_LINK_STATUS_WAIT_CNT);
 }
 
 static int hclge_config_switch_param(struct hclge_dev *hdev, int vfid,