igb: VFTA Table Fix for i350 devices

Due to a hardware problem, writes to the VFTA register can
theoretically fail. Although the likelihood of this is very low.
This patch adds a shadow vfta in the adapter struct for reading
and adds new write functions for these devices to work around the problem.

Signed-off-by: Carolyn Wyborny <carolyn.wyborny@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 53 insertions, 3 deletions

diff --git a/drivers/net/ethernet/intel/igb/e1000_mac.c b/drivers/net/ethernet/intel/igb/e1000_mac.c
index bad3e1425ff..73aac082c44 100644
--- a/drivers/net/ethernet/intel/igb/e1000_mac.c
+++ b/drivers/net/ethernet/intel/igb/e1000_mac.c
@@ -117,6 +117,50 @@ static void igb_write_vfta(struct e1000_hw *hw, u32 offset, u32 value)
 	wrfl();
 }
 
+/* Due to a hw errata, if the host tries to  configure the VFTA register
+ * while performing queries from the BMC or DMA, then the VFTA in some
+ * cases won't be written.
+ */
+
+/**
+ *  igb_clear_vfta_i350 - Clear VLAN filter table
+ *  @hw: pointer to the HW structure
+ *
+ *  Clears the register array which contains the VLAN filter table by
+ *  setting all the values to 0.
+ **/
+void igb_clear_vfta_i350(struct e1000_hw *hw)
+{
+	u32 offset;
+	int i;
+
+	for (offset = 0; offset < E1000_VLAN_FILTER_TBL_SIZE; offset++) {
+		for (i = 0; i < 10; i++)
+			array_wr32(E1000_VFTA, offset, 0);
+
+		wrfl();
+	}
+}
+
+/**
+ *  igb_write_vfta_i350 - Write value to VLAN filter table
+ *  @hw: pointer to the HW structure
+ *  @offset: register offset in VLAN filter table
+ *  @value: register value written to VLAN filter table
+ *
+ *  Writes value at the given offset in the register array which stores
+ *  the VLAN filter table.
+ **/
+void igb_write_vfta_i350(struct e1000_hw *hw, u32 offset, u32 value)
+{
+	int i;
+
+	for (i = 0; i < 10; i++)
+		array_wr32(E1000_VFTA, offset, value);
+
+	wrfl();
+}
+
 /**
  *  igb_init_rx_addrs - Initialize receive address's
  *  @hw: pointer to the HW structure
@@ -155,9 +199,12 @@ s32 igb_vfta_set(struct e1000_hw *hw, u32 vid, bool add)
 {
 	u32 index = (vid >> E1000_VFTA_ENTRY_SHIFT) & E1000_VFTA_ENTRY_MASK;
 	u32 mask = 1 << (vid & E1000_VFTA_ENTRY_BIT_SHIFT_MASK);
-	u32 vfta = array_rd32(E1000_VFTA, index);
+	u32 vfta;
+	struct igb_adapter *adapter = hw->back;
 	s32 ret_val = 0;
 
+	vfta = adapter->shadow_vfta[index];
+
 	/* bit was set/cleared before we started */
 	if ((!!(vfta & mask)) == add) {
 		ret_val = -E1000_ERR_CONFIG;
@@ -167,8 +214,11 @@ s32 igb_vfta_set(struct e1000_hw *hw, u32 vid, bool add)
 		else
 			vfta &= ~mask;
 	}
-
-	igb_write_vfta(hw, index, vfta);
+	if (hw->mac.type == e1000_i350)
+		igb_write_vfta_i350(hw, index, vfta);
+	else
+		igb_write_vfta(hw, index, vfta);
+	adapter->shadow_vfta[index] = vfta;
 
 	return ret_val;
 }