From b8a2ca19bc1479745952967ec998fd92de92ec85 Mon Sep 17 00:00:00 2001 From: Emil Tantilov Date: Wed, 13 Aug 2014 05:52:13 +0000 Subject: [PATCH] ixgbevf: introduce delay for checking VFLINKS on 82599 VFLINKS.LINKUP bit tends to flap when a DA or SFP+ cable is disconnected. It can take up to 500 usecs for the LINKUP bit to be correct. This patch resolves the issue by introducing a delay for 82599 VFs of at least 500 usecs to make sure the VFLINKS value is correct. Signed-off-by: Emil Tantilov Tested-by: Phil Schmitt Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/ixgbevf/vf.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/net/ethernet/intel/ixgbevf/vf.c b/drivers/net/ethernet/intel/ixgbevf/vf.c index 4d44d64ae387..9cddd56d02c3 100644 --- a/drivers/net/ethernet/intel/ixgbevf/vf.c +++ b/drivers/net/ethernet/intel/ixgbevf/vf.c @@ -434,6 +434,21 @@ static s32 ixgbevf_check_mac_link_vf(struct ixgbe_hw *hw, if (!(links_reg & IXGBE_LINKS_UP)) goto out; + /* for SFP+ modules and DA cables on 82599 it can take up to 500usecs + * before the link status is correct + */ + if (mac->type == ixgbe_mac_82599_vf) { + int i; + + for (i = 0; i < 5; i++) { + udelay(100); + links_reg = IXGBE_READ_REG(hw, IXGBE_VFLINKS); + + if (!(links_reg & IXGBE_LINKS_UP)) + goto out; + } + } + switch (links_reg & IXGBE_LINKS_SPEED_82599) { case IXGBE_LINKS_SPEED_10G_82599: *speed = IXGBE_LINK_SPEED_10GB_FULL; -- 2.20.1