ixgbe: Force VLNCTRL.VFE to be set in all VMDq paths

BugLink: http://bugs.launchpad.net/bugs/1658491

When I was adding the code for enabling VLAN promiscuous mode with SR-IOV
enabled I had inadvertently left the VLNCTRL.VFE bit unchanged as I has
assumed there was code in another path that was setting it when we enabled
SR-IOV.  This wasn't the case and as a result we were just disabling VLAN
filtering for all the VFs apparently.

Also the previous patches were always clearing CFIEN which was always set
to 0 by the hardware anyway so I am dropping the redundant bit clearing.

Fixes: 16369564 ("ixgbe: Add support for VLAN promiscuous with SR-IOV")
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
(cherry-picked from commit f60439bc)
Fixes: 6c39aa93 ("ixgbe: Add support for VLAN promiscuous with SR-IOV")
Signed-off-by: Dan Streetman <dan.streetman@canonical.com>
Acked-by: Tim Gardner <tim.gardner@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>

drivers/net/ethernet/intel/ixgbe/ixgbe_main.c

@@ -4056,6 +4056,8 @@ static void ixgbe_vlan_promisc_enable(struct ixgbe_adapter *adapter)
 	struct ixgbe_hw *hw = &adapter->hw;
 	u32 vlnctrl, i;
 
+	vlnctrl = IXGBE_READ_REG(hw, IXGBE_VLNCTRL);
+
 	switch (hw->mac.type) {
 	case ixgbe_mac_82599EB:
 	case ixgbe_mac_X540:
@@ -4067,8 +4069,7 @@ static void ixgbe_vlan_promisc_enable(struct ixgbe_adapter *adapter)
 		/* fall through */
 	case ixgbe_mac_82598EB:
 		/* legacy case, we can just disable VLAN filtering */
-		vlnctrl = IXGBE_READ_REG(hw, IXGBE_VLNCTRL);
-		vlnctrl &= ~(IXGBE_VLNCTRL_VFE | IXGBE_VLNCTRL_CFIEN);
+		vlnctrl &= ~IXGBE_VLNCTRL_VFE;
 		IXGBE_WRITE_REG(hw, IXGBE_VLNCTRL, vlnctrl);
 		return;
 	}
@@ -4080,6 +4081,10 @@ static void ixgbe_vlan_promisc_enable(struct ixgbe_adapter *adapter)
 	/* Set flag so we don't redo unnecessary work */
 	adapter->flags2 |= IXGBE_FLAG2_VLAN_PROMISC;
 
+	/* For VMDq and SR-IOV we must leave VLAN filtering enabled */
+	vlnctrl |= IXGBE_VLNCTRL_VFE;
+	IXGBE_WRITE_REG(hw, IXGBE_VLNCTRL, vlnctrl);
+
 	/* Add PF to all active pools */
 	for (i = IXGBE_VLVF_ENTRIES; --i;) {
 		u32 reg_offset = IXGBE_VLVFB(i * 2 + VMDQ_P(0) / 32);
@@ -4146,6 +4151,11 @@ static void ixgbe_vlan_promisc_disable(struct ixgbe_adapter *adapter)
 	struct ixgbe_hw *hw = &adapter->hw;
 	u32 vlnctrl, i;
 
+	/* Set VLAN filtering to enabled */
+	vlnctrl = IXGBE_READ_REG(hw, IXGBE_VLNCTRL);
+	vlnctrl |= IXGBE_VLNCTRL_VFE;
+	IXGBE_WRITE_REG(hw, IXGBE_VLNCTRL, vlnctrl);
+
 	switch (hw->mac.type) {
 	case ixgbe_mac_82599EB:
 	case ixgbe_mac_X540:
@@ -4156,10 +4166,6 @@ static void ixgbe_vlan_promisc_disable(struct ixgbe_adapter *adapter)
 			break;
 		/* fall through */
 	case ixgbe_mac_82598EB:
-		vlnctrl = IXGBE_READ_REG(hw, IXGBE_VLNCTRL);
-		vlnctrl &= ~IXGBE_VLNCTRL_CFIEN;
-		vlnctrl |= IXGBE_VLNCTRL_VFE;
-		IXGBE_WRITE_REG(hw, IXGBE_VLNCTRL, vlnctrl);
 		return;
 	}