e1000e: convert head, tail and itr_register offsets to __iomem pointers

The Tx/Rx head and tail registers and itr_register are always at known
addresses based on the __iomem address at which the PCI region (from BAR 0)
is mapped and known offsets within the region for each of these registers.
Store and use the full address rather than just the region offset to reduce
unnecessary address calculations.  Also, change current u8 __iomem pointers
to void __iomem pointers.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index b196d79..462bdee 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -550,7 +550,7 @@
  * which has bit 24 set while ME is accessing Host CSR registers, wait
  * if it is set and try again a number of times.
  **/
-static inline s32 e1000e_update_tail_wa(struct e1000_hw *hw, u8 __iomem * tail,
+static inline s32 e1000e_update_tail_wa(struct e1000_hw *hw, void __iomem *tail,
 					unsigned int i)
 {
 	unsigned int j = 0;
@@ -569,10 +569,9 @@
 
 static void e1000e_update_rdt_wa(struct e1000_adapter *adapter, unsigned int i)
 {
-	u8 __iomem *tail = (adapter->hw.hw_addr + adapter->rx_ring->tail);
 	struct e1000_hw *hw = &adapter->hw;
 
-	if (e1000e_update_tail_wa(hw, tail, i)) {
+	if (e1000e_update_tail_wa(hw, adapter->rx_ring->tail, i)) {
 		u32 rctl = er32(RCTL);
 		ew32(RCTL, rctl & ~E1000_RCTL_EN);
 		e_err("ME firmware caused invalid RDT - resetting\n");
@@ -582,10 +581,9 @@
 
 static void e1000e_update_tdt_wa(struct e1000_adapter *adapter, unsigned int i)
 {
-	u8 __iomem *tail = (adapter->hw.hw_addr + adapter->tx_ring->tail);
 	struct e1000_hw *hw = &adapter->hw;
 
-	if (e1000e_update_tail_wa(hw, tail, i)) {
+	if (e1000e_update_tail_wa(hw, adapter->tx_ring->tail, i)) {
 		u32 tctl = er32(TCTL);
 		ew32(TCTL, tctl & ~E1000_TCTL_EN);
 		e_err("ME firmware caused invalid TDT - resetting\n");
@@ -651,7 +649,7 @@
 			if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
 				e1000e_update_rdt_wa(adapter, i);
 			else
-				writel(i, adapter->hw.hw_addr + rx_ring->tail);
+				writel(i, rx_ring->tail);
 		}
 		i++;
 		if (i == rx_ring->count)
@@ -754,8 +752,7 @@
 			if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
 				e1000e_update_rdt_wa(adapter, i << 1);
 			else
-				writel(i << 1,
-				       adapter->hw.hw_addr + rx_ring->tail);
+				writel(i << 1, rx_ring->tail);
 		}
 
 		i++;
@@ -841,7 +838,7 @@
 		if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
 			e1000e_update_rdt_wa(adapter, i);
 		else
-			writel(i, adapter->hw.hw_addr + rx_ring->tail);
+			writel(i, rx_ring->tail);
 	}
 }
 
@@ -1076,8 +1073,8 @@
 	      "PHY 1000BASE-T Status  <%x>\n"
 	      "PHY Extended Status    <%x>\n"
 	      "PCI Status             <%x>\n",
-	      readl(adapter->hw.hw_addr + tx_ring->head),
-	      readl(adapter->hw.hw_addr + tx_ring->tail),
+	      readl(tx_ring->head),
+	      readl(tx_ring->tail),
 	      tx_ring->next_to_use,
 	      tx_ring->next_to_clean,
 	      tx_ring->buffer_info[eop].time_stamp,
@@ -1617,8 +1614,8 @@
 	rx_ring->next_to_use = 0;
 	adapter->flags2 &= ~FLAG2_IS_DISCARDING;
 
-	writel(0, adapter->hw.hw_addr + rx_ring->head);
-	writel(0, adapter->hw.hw_addr + rx_ring->tail);
+	writel(0, rx_ring->head);
+	writel(0, rx_ring->tail);
 }
 
 static void e1000e_downshift_workaround(struct work_struct *work)
@@ -1814,7 +1811,7 @@
 	 */
 	if (adapter->rx_ring->set_itr) {
 		writel(1000000000 / (adapter->rx_ring->itr_val * 256),
-		       adapter->hw.hw_addr + adapter->rx_ring->itr_register);
+		       adapter->rx_ring->itr_register);
 		adapter->rx_ring->set_itr = 0;
 	}
 
@@ -1855,9 +1852,9 @@
 	adapter->eiac_mask |= rx_ring->ims_val;
 	if (rx_ring->itr_val)
 		writel(1000000000 / (rx_ring->itr_val * 256),
-		       hw->hw_addr + rx_ring->itr_register);
+		       rx_ring->itr_register);
 	else
-		writel(1, hw->hw_addr + rx_ring->itr_register);
+		writel(1, rx_ring->itr_register);
 	ivar = E1000_IVAR_INT_ALLOC_VALID | vector;
 
 	/* Configure Tx vector */
@@ -1865,9 +1862,9 @@
 	vector++;
 	if (tx_ring->itr_val)
 		writel(1000000000 / (tx_ring->itr_val * 256),
-		       hw->hw_addr + tx_ring->itr_register);
+		       tx_ring->itr_register);
 	else
-		writel(1, hw->hw_addr + tx_ring->itr_register);
+		writel(1, tx_ring->itr_register);
 	adapter->eiac_mask |= tx_ring->ims_val;
 	ivar |= ((E1000_IVAR_INT_ALLOC_VALID | vector) << 8);
 
@@ -1982,7 +1979,8 @@
 			  netdev);
 	if (err)
 		goto out;
-	adapter->rx_ring->itr_register = E1000_EITR_82574(vector);
+	adapter->rx_ring->itr_register = adapter->hw.hw_addr +
+	    E1000_EITR_82574(vector);
 	adapter->rx_ring->itr_val = adapter->itr;
 	vector++;
 
@@ -1997,7 +1995,8 @@
 			  netdev);
 	if (err)
 		goto out;
-	adapter->tx_ring->itr_register = E1000_EITR_82574(vector);
+	adapter->tx_ring->itr_register = adapter->hw.hw_addr +
+	    E1000_EITR_82574(vector);
 	adapter->tx_ring->itr_val = adapter->itr;
 	vector++;
 
@@ -2288,8 +2287,8 @@
 	tx_ring->next_to_use = 0;
 	tx_ring->next_to_clean = 0;
 
-	writel(0, adapter->hw.hw_addr + tx_ring->head);
-	writel(0, adapter->hw.hw_addr + tx_ring->tail);
+	writel(0, tx_ring->head);
+	writel(0, tx_ring->tail);
 }
 
 /**
@@ -2773,8 +2772,8 @@
 	ew32(TDLEN, tdlen);
 	ew32(TDH, 0);
 	ew32(TDT, 0);
-	tx_ring->head = E1000_TDH;
-	tx_ring->tail = E1000_TDT;
+	tx_ring->head = adapter->hw.hw_addr + E1000_TDH;
+	tx_ring->tail = adapter->hw.hw_addr + E1000_TDT;
 
 	/* Set the default values for the Tx Inter Packet Gap timer */
 	tipg = DEFAULT_82543_TIPG_IPGT_COPPER;          /*  8  */
@@ -3088,8 +3087,8 @@
 	ew32(RDLEN, rdlen);
 	ew32(RDH, 0);
 	ew32(RDT, 0);
-	rx_ring->head = E1000_RDH;
-	rx_ring->tail = E1000_RDT;
+	rx_ring->head = adapter->hw.hw_addr + E1000_RDH;
+	rx_ring->tail = adapter->hw.hw_addr + E1000_RDT;
 
 	/* Enable Receive Checksum Offload for TCP and UDP */
 	rxcsum = er32(RXCSUM);
@@ -4914,7 +4913,7 @@
 	if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
 		e1000e_update_tdt_wa(adapter, i);
 	else
-		writel(i, adapter->hw.hw_addr + tx_ring->tail);
+		writel(i, tx_ring->tail);
 
 	/*
 	 * we need this if more than one processor can write to our tail