From bf03085f85112eac2d19036ea3003071220285bb Mon Sep 17 00:00:00 2001 From: Matthew Vick Date: Fri, 16 Mar 2012 09:03:00 +0000 Subject: e1000e: Guarantee descriptor writeback flush success. In rare circumstances, a descriptor writeback flush may not work if it arrives on a specific clock cycle as a writeback request is going out. Signed-off-by: Matthew Vick Tested-by: Aaron Brown Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/e1000e/netdev.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'drivers') diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c index 6878601f20c..19ab2154802 100644 --- a/drivers/net/ethernet/intel/e1000e/netdev.c +++ b/drivers/net/ethernet/intel/e1000e/netdev.c @@ -1059,6 +1059,13 @@ static void e1000_print_hw_hang(struct work_struct *work) ew32(TIDV, adapter->tx_int_delay | E1000_TIDV_FPD); /* execute the writes immediately */ e1e_flush(); + /* + * Due to rare timing issues, write to TIDV again to ensure + * the write is successful + */ + ew32(TIDV, adapter->tx_int_delay | E1000_TIDV_FPD); + /* execute the writes immediately */ + e1e_flush(); adapter->tx_hang_recheck = true; return; } @@ -3616,6 +3623,16 @@ static void e1000e_flush_descriptors(struct e1000_adapter *adapter) /* execute the writes immediately */ e1e_flush(); + + /* + * due to rare timing issues, write to TIDV/RDTR again to ensure the + * write is successful + */ + ew32(TIDV, adapter->tx_int_delay | E1000_TIDV_FPD); + ew32(RDTR, adapter->rx_int_delay | E1000_RDTR_FPD); + + /* execute the writes immediately */ + e1e_flush(); } static void e1000e_update_stats(struct e1000_adapter *adapter); -- cgit v1.2.3