[PATCH 5.5 018/151] net: hns3: fix a not link up issue when fibre port supports autoneg

[Greg Kroah-Hartman]

From: Jian Shen <shenjian15@xxxxxxxxxx>

[ Upstream commit 68e1006f618e509fc7869259fe83ceec4a95dac3 ]

When fibre port supports auto-negotiation, the IMP(Intelligent
Management Process) processes the speed of auto-negotiation
and the  user's speed separately.
For below case, the port will get a not link up problem.
step 1: disables auto-negotiation and sets speed to A, then
the driver's MAC speed will be updated to A.
step 2: enables auto-negotiation and MAC gets negotiated
speed B, then the driver's MAC speed will be updated to B
through querying in periodical task.
step 3: MAC gets new negotiated speed A.
step 4: disables auto-negotiation and sets speed to B before
periodical task query new MAC speed A, the driver will  ignore
the speed configuration.

This patch fixes it by skipping speed and duplex checking when
fibre port supports auto-negotiation.

Fixes: 22f48e24a23d ("net: hns3: add autoneg and change speed support for fibre port")
Signed-off-by: Jian Shen <shenjian15@xxxxxxxxxx>
Signed-off-by: Huazhong Tan <tanhuazhong@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
@@ -2450,10 +2450,12 @@ static int hclge_cfg_mac_speed_dup_hw(st
 
 int hclge_cfg_mac_speed_dup(struct hclge_dev *hdev, int speed, u8 duplex)
 {
+	struct hclge_mac *mac = &hdev->hw.mac;
 	int ret;
 
 	duplex = hclge_check_speed_dup(duplex, speed);
-	if (hdev->hw.mac.speed == speed && hdev->hw.mac.duplex == duplex)
+	if (!mac->support_autoneg && mac->speed == speed &&
+	    mac->duplex == duplex)
 		return 0;
 
 	ret = hclge_cfg_mac_speed_dup_hw(hdev, speed, duplex);