From ae92baa40e56fd2d6dabf451fa6a2289f0d10c36 Mon Sep 17 00:00:00 2001
From: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Date: Wed, 17 Feb 2021 00:37:10 +0530
Subject: [PATCH 04/19] net: amd-xgbe: Fix network fluctuations when using 1G
BELFUSE SFP
Git-commit: 9eab3fdb419916f66a72d1572f68d82cd9b3f963
Patch-mainline: v5.12-rc1
References: git-fixes
Frequent link up/down events can happen when a Bel Fuse SFP part is
connected to the amd-xgbe device. Try to avoid the frequent link
issues by resetting the PHY as documented in Bel Fuse SFP datasheets.
Fixes: e722ec82374b ("amd-xgbe: Update the BelFuse quirk to support SGMII")
Co-developed-by: Sudheesh Mavila <sudheesh.mavila@amd.com>
Signed-off-by: Sudheesh Mavila <sudheesh.mavila@amd.com>
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
drivers/net/ethernet/amd/xgbe/xgbe-phy-v2.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-phy-v2.c b/drivers/net/ethernet/amd/xgbe/xgbe-phy-v2.c
index ee6c92eb2fda..726f4cbd6846 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-phy-v2.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-phy-v2.c
@@ -912,6 +912,9 @@ static bool xgbe_phy_belfuse_phy_quirks(struct xgbe_prv_data *pdata)
if ((phy_id & 0xfffffff0) != 0x03625d10)
return false;
+ /* Reset PHY - wait for self-clearing reset bit to clear */
+ genphy_soft_reset(phy_data->phydev);
+
/* Disable RGMII mode */
phy_write(phy_data->phydev, 0x18, 0x7007);
reg = phy_read(phy_data->phydev, 0x18);
--
2.16.4