net: hns: fix port not available after testing loopback

After running command "ethtool -t eth0", eth0 can not be connected to
network. It is caused by the changing the inner loopback register and
this register cannot be changed when hns connected to network. The
routine of setting this register needs to be removed and using promisc
mode to let the packet looped back pass by dsaf mode.

Reported-by: Jun He <hjat2005@huawei.com>
Signed-off-by: Kejian Yan <yankejian@huawei.com>
Reviewed-by: Yisen Zhaung <yisen.zhuang@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/net/ethernet/hisilicon/hns/hns_ae_adapt.c

@@ -678,9 +678,6 @@ static int hns_ae_config_loopback(struct hnae_handle *handle,
 		ret = -EINVAL;
 	}
 
-	if (!ret)
-		hns_dsaf_set_inner_lb(mac_cb->dsaf_dev, mac_cb->mac_id, en);
-
 	return ret;
 }
 

drivers/net/ethernet/hisilicon/hns/hns_dsaf_main.c

@@ -768,16 +768,6 @@ void hns_dsaf_set_promisc_mode(struct dsaf_device *dsaf_dev, u32 en)
 				 DSAF_CFG_MIX_MODE_S, !!en);
 }
 
-void hns_dsaf_set_inner_lb(struct dsaf_device *dsaf_dev, u32 mac_id, u32 en)
-{
-	if (AE_IS_VER1(dsaf_dev->dsaf_ver) ||
-	    dsaf_dev->mac_cb[mac_id]->mac_type == HNAE_PORT_DEBUG)
-		return;
-
-	dsaf_set_dev_bit(dsaf_dev, DSAFV2_SERDES_LBK_0_REG + 4 * mac_id,
-			 DSAFV2_SERDES_LBK_EN_B, !!en);
-}
-
 /**
  * hns_dsaf_tbl_stat_en - tbl
  * @dsaf_id: dsa fabric id

drivers/net/ethernet/hisilicon/hns/hns_dsaf_main.h

@@ -466,6 +466,5 @@ void hns_dsaf_get_rx_mac_pause_en(struct dsaf_device *dsaf_dev, int mac_id,
 				  u32 *en);
 int hns_dsaf_set_rx_mac_pause_en(struct dsaf_device *dsaf_dev, int mac_id,
 				 u32 en);
-void hns_dsaf_set_inner_lb(struct dsaf_device *dsaf_dev, u32 mac_id, u32 en);
 
 #endif /* __HNS_DSAF_MAIN_H__ */

drivers/net/ethernet/hisilicon/hns/hns_ethtool.c

@@ -342,6 +342,13 @@ static int __lb_setup(struct net_device *ndev,
 		break;
 	}
 
+	if (!ret) {
+		if (loop == MAC_LOOP_NONE)
+			h->dev->ops->set_promisc_mode(
+				h, ndev->flags & IFF_PROMISC);
+		else
+			h->dev->ops->set_promisc_mode(h, 1);
+	}
 	return ret;
 }