e1000e: convert driver to use extended descriptors

Some features currently not supported by the driver (e.g. RSS) require the
use of extended descriptors, but the driver is setup to only use legacy
descriptors in all modes except for when jumbo frames are enabled on some
parts.  Convert the driver to always use extended descriptors in order to
enable the forthcoming support of these other features.
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Jeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/e1000e/e1000.h

@@ -456,8 +456,9 @@ struct e1000_info {
 
 #define E1000_RX_DESC_PS(R, i)	    \
 	(&(((union e1000_rx_desc_packet_split *)((R).desc))[i]))
+#define E1000_RX_DESC_EXT(R, i)	    \
+	(&(((union e1000_rx_desc_extended *)((R).desc))[i]))
 #define E1000_GET_DESC(R, i, type)	(&(((struct type *)((R).desc))[i]))
-#define E1000_RX_DESC(R, i)		E1000_GET_DESC(R, i, e1000_rx_desc)
 #define E1000_TX_DESC(R, i)		E1000_GET_DESC(R, i, e1000_tx_desc)
 #define E1000_CONTEXT_DESC(R, i)	E1000_GET_DESC(R, i, e1000_context_desc)
 

drivers/net/ethernet/intel/e1000e/ethtool.c

@@ -1195,7 +1195,7 @@ static int e1000_setup_desc_rings(struct e1000_adapter *adapter)
 		goto err_nomem;
 	}
 
-	rx_ring->size = rx_ring->count * sizeof(struct e1000_rx_desc);
+	rx_ring->size = rx_ring->count * sizeof(union e1000_rx_desc_extended);
 	rx_ring->desc = dma_alloc_coherent(&pdev->dev, rx_ring->size,
 					   &rx_ring->dma, GFP_KERNEL);
 	if (!rx_ring->desc) {
@@ -1220,7 +1220,7 @@ static int e1000_setup_desc_rings(struct e1000_adapter *adapter)
 	ew32(RCTL, rctl);
 
 	for (i = 0; i < rx_ring->count; i++) {
-		struct e1000_rx_desc *rx_desc = E1000_RX_DESC(*rx_ring, i);
+		union e1000_rx_desc_extended *rx_desc;
 		struct sk_buff *skb;
 
 		skb = alloc_skb(2048 + NET_IP_ALIGN, GFP_KERNEL);
@@ -1238,8 +1238,9 @@ static int e1000_setup_desc_rings(struct e1000_adapter *adapter)
 			ret_val = 8;
 			goto err_nomem;
 		}
-		rx_desc->buffer_addr =
-			cpu_to_le64(rx_ring->buffer_info[i].dma);
+		rx_desc = E1000_RX_DESC_EXT(*rx_ring, i);
+		rx_desc->read.buffer_addr =
+		    cpu_to_le64(rx_ring->buffer_info[i].dma);
 		memset(skb->data, 0x00, skb->len);
 	}