[PATCH 4.9 091/129] e1000e: add workaround for possible stalled packet
From: Greg Kroah-Hartman
Date: Thu Oct 03 2019 - 13:36:46 EST
From: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
[ Upstream commit e5e9a2ecfe780975820e157b922edee715710b66 ]
This works around a possible stalled packet issue, which may occur due to
clock recovery from the PCH being too slow, when the LAN is transitioning
from K1 at 1G link speed.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204057
Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
Tested-by: Aaron Brown <aaron.f.brown@xxxxxxxxx>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/intel/e1000e/ich8lan.c | 10 ++++++++++
drivers/net/ethernet/intel/e1000e/ich8lan.h | 2 +-
2 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.c b/drivers/net/ethernet/intel/e1000e/ich8lan.c
index dc7d671b903c5..625008e8cb0df 100644
--- a/drivers/net/ethernet/intel/e1000e/ich8lan.c
+++ b/drivers/net/ethernet/intel/e1000e/ich8lan.c
@@ -1447,6 +1447,16 @@ static s32 e1000_check_for_copper_link_ich8lan(struct e1000_hw *hw)
else
phy_reg |= 0xFA;
e1e_wphy_locked(hw, I217_PLL_CLOCK_GATE_REG, phy_reg);
+
+ if (speed == SPEED_1000) {
+ hw->phy.ops.read_reg_locked(hw, HV_PM_CTRL,
+ &phy_reg);
+
+ phy_reg |= HV_PM_CTRL_K1_CLK_REQ;
+
+ hw->phy.ops.write_reg_locked(hw, HV_PM_CTRL,
+ phy_reg);
+ }
}
hw->phy.ops.release(hw);
diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.h b/drivers/net/ethernet/intel/e1000e/ich8lan.h
index 67163ca898ba2..6374c8fc76a8d 100644
--- a/drivers/net/ethernet/intel/e1000e/ich8lan.h
+++ b/drivers/net/ethernet/intel/e1000e/ich8lan.h
@@ -227,7 +227,7 @@
/* PHY Power Management Control */
#define HV_PM_CTRL PHY_REG(770, 17)
-#define HV_PM_CTRL_PLL_STOP_IN_K1_GIGA 0x100
+#define HV_PM_CTRL_K1_CLK_REQ 0x200
#define HV_PM_CTRL_K1_ENABLE 0x4000
#define I217_PLL_CLOCK_GATE_REG PHY_REG(772, 28)
--
2.20.1