IXGBE_VFTXDCTL
txdctl = IXGBE_READ_REG(hw, IXGBE_VFTXDCTL(i));
IXGBE_WRITE_REG(hw, IXGBE_VFTXDCTL(i), txdctl);
txdctl = IXGBE_READ_REG(hw, IXGBE_VFTXDCTL(i));
IXGBE_WRITE_REG(hw, IXGBE_VFTXDCTL(i), txdctl);
IXGBE_WRITE_REG(hw, IXGBE_VFTXDCTL(i), 0);
IXGBE_VFWRITE_REG(hw, IXGBE_VFTXDCTL(i), IXGBE_TXDCTL_SWFLSH);