e1000e: 82577: workaround for link drop issue
When connected to certain switches, the 82577 PHY might drop link
unexpectedly. Work around the issue by setting the Mean Square Error
higher than the hardware default.
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.c b/drivers/net/ethernet/intel/e1000e/ich8lan.c
index 8004d71..a7d6c87 100644
--- a/drivers/net/ethernet/intel/e1000e/ich8lan.c
+++ b/drivers/net/ethernet/intel/e1000e/ich8lan.c
@@ -157,7 +157,8 @@
#define I82579_EMI_ADDR 0x10
#define I82579_EMI_DATA 0x11
#define I82579_LPI_UPDATE_TIMER 0x4805 /* in 40ns units + 40 ns base value */
-#define I82579_MSE_THRESHOLD 0x084F /* Mean Square Error Threshold */
+#define I82579_MSE_THRESHOLD 0x084F /* 82579 Mean Square Error Threshold */
+#define I82577_MSE_THRESHOLD 0x0887 /* 82577 Mean Square Error Threshold */
#define I82579_MSE_LINK_DOWN 0x2411 /* MSE count before dropping link */
#define I217_EEE_ADVERTISEMENT 0x8001 /* IEEE MMD Register 7.60 */
#define I217_EEE_LP_ABILITY 0x8002 /* IEEE MMD Register 7.61 */
@@ -1809,6 +1810,11 @@
if (ret_val)
goto release;
ret_val = e1e_wphy_locked(hw, BM_PORT_GEN_CFG, phy_data & 0x00FF);
+ if (ret_val)
+ goto release;
+
+ /* set MSE higher to enable link to stay up when noise is high */
+ ret_val = e1000_write_emi_reg_locked(hw, I82577_MSE_THRESHOLD, 0x0034);
release:
hw->phy.ops.release(hw);