net: hns3: not allow SSU loopback while execute ethtool -t dev

The current loopback mode is to add 0x1F to the SMAC address
as the DMAC address and enable the promiscuous mode.
However, if the VF address is the same as the DMAC address,
the loopback test fails.

Loopback can be enabled in three places: SSU, MAC, and serdes.
By default, SSU loopback is enabled, so if the SMAC and the DMAC
are the same, the packets are looped back in the SSU. If SSU loopback
is disabled, packets can reach MAC even if SMAC is the same as DMAC.

Therefore, this patch disables the SSU loopback before the loopback
test. In this way, the SMAC and DMAC can be the same, and the
promiscuous mode does not need to be enabled. And this is not
valid in version 0x20.

This patch also uses a macro to replace 0x1F.

Fixes: c39c4d98dc65 ("net: hns3: Add mac loopback selftest support in hns3 driver")
Signed-off-by: Yufeng Mo <moyufeng@huawei.com>
Reviewed-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 38 insertions, 0 deletions

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
index dc22b84641a7..ce4b2280a8b0 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
@@ -6211,6 +6211,30 @@ static void hclge_cfg_mac_mode(struct hclge_dev *hdev, bool enable)
 			"mac enable fail, ret =%d.\n", ret);
 }
 
+static int hclge_config_switch_param(struct hclge_dev *hdev, int vfid,
+				     u8 switch_param, u8 param_mask)
+{
+	struct hclge_mac_vlan_switch_cmd *req;
+	struct hclge_desc desc;
+	u32 func_id;
+	int ret;
+
+	func_id = hclge_get_port_number(HOST_PORT, 0, vfid, 0);
+	req = (struct hclge_mac_vlan_switch_cmd *)desc.data;
+	hclge_cmd_setup_basic_desc(&desc, HCLGE_OPC_MAC_VLAN_SWITCH_PARAM,
+				   false);
+	req->roce_sel = HCLGE_MAC_VLAN_NIC_SEL;
+	req->func_id = cpu_to_le32(func_id);
+	req->switch_param = switch_param;
+	req->param_mask = param_mask;
+
+	ret = hclge_cmd_send(&hdev->hw, &desc, 1);
+	if (ret)
+		dev_err(&hdev->pdev->dev,
+			"set mac vlan switch parameter fail, ret = %d\n", ret);
+	return ret;
+}
+
 static void hclge_phy_link_status_wait(struct hclge_dev *hdev,
 				       int link_ret)
 {
@@ -6465,6 +6489,20 @@ static int hclge_set_loopback(struct hnae3_handle *handle,
 	struct hclge_dev *hdev = vport->back;
 	int i, ret;
 
+	/* Loopback can be enabled in three places: SSU, MAC, and serdes. By
+	 * default, SSU loopback is enabled, so if the SMAC and the DMAC are
+	 * the same, the packets are looped back in the SSU. If SSU loopback
+	 * is disabled, packets can reach MAC even if SMAC is the same as DMAC.
+	 */
+	if (hdev->pdev->revision >= 0x21) {
+		u8 switch_param = en ? 0 : BIT(HCLGE_SWITCH_ALW_LPBK_B);
+
+		ret = hclge_config_switch_param(hdev, PF_VPORT_ID, switch_param,
+						HCLGE_SWITCH_ALW_LPBK_MASK);
+		if (ret)
+			return ret;
+	}
+
 	switch (loop_mode) {
 	case HNAE3_LOOP_APP:
 		ret = hclge_set_app_loopback(hdev, en);