e1000e: workaround a Tx hang on 82577/82578
With bi-directional stress traffic, the receiver could hang causing the
hardware to stop and a "Detected Tx Unit Hang" message dumped to the system
logfile. Temporarily workaround this issue by disabling Tx flow control by
default. The issue is currently being investigated and a follow-on patch
will be provided to revert this when it is resolved.
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/e1000e/ich8lan.c b/drivers/net/e1000e/ich8lan.c
index b69c819..9e23f50f 100644
--- a/drivers/net/e1000e/ich8lan.c
+++ b/drivers/net/e1000e/ich8lan.c
@@ -2348,8 +2348,13 @@
* the default flow control setting, so we explicitly
* set it to full.
*/
- if (hw->fc.requested_mode == e1000_fc_default)
- hw->fc.requested_mode = e1000_fc_full;
+ if (hw->fc.requested_mode == e1000_fc_default) {
+ /* Workaround h/w hang when Tx flow control enabled */
+ if (hw->mac.type == e1000_pchlan)
+ hw->fc.requested_mode = e1000_fc_rx_pause;
+ else
+ hw->fc.requested_mode = e1000_fc_full;
+ }
/*
* Save off the requested flow control mode for use later. Depending