commit: d0efa8f23a644f7cb7d1f8e78dd9a223efa412a3 From: Tushar Dave <[email protected]> Date: Thu, 12 Jul 2012 08:56:56 +0000 Subject: e1000e: Correct link check logic for 82571 serdes
SYNCH bit and IV bit of RXCW register are sticky. Before examining these bits, RXCW should be read twice to filter out one-time false events and have correct values for these bits. Incorrect values of these bits in link check logic can cause weird link stability issues if auto-negotiation fails. CC: stable <[email protected]> [2.6.38+] Reported-by: Dean Nelson <[email protected]> Signed-off-by: Tushar Dave <[email protected]> Reviewed-by: Bruce Allan <[email protected]> Tested-by: Jeff Pieper <[email protected]> Signed-off-by: Jeff Kirsher <[email protected]> --- drivers/net/ethernet/intel/e1000e/82571.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/drivers/net/ethernet/intel/e1000e/82571.c b/drivers/net/ethernet/intel/e1000e/82571.c index 36db4df..1f063dc 100644 --- a/drivers/net/ethernet/intel/e1000e/82571.c +++ b/drivers/net/ethernet/intel/e1000e/82571.c @@ -1572,6 +1572,9 @@ static s32 e1000_check_for_serdes_link_82571(struct e1000_hw *hw) ctrl = er32(CTRL); status = er32(STATUS); rxcw = er32(RXCW); + /* SYNCH bit and IV bit are sticky */ + udelay(10); + rxcw = er32(RXCW); if ((rxcw & E1000_RXCW_SYNCH) && !(rxcw & E1000_RXCW_IV)) { -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
