r8152: support rx checksum

Support hw rx checksum for TCP and UDP packets.

Change-Id: I3bb3cefe4d9dbd98996fa975256545f35f393eae
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Aly Hirani <ahirani@nvidia.com>
Reviewed-on: http://git-master/r/390296
(cherry picked from commit 930a7af20283f78e3f5e5e4c70615c84c1ee29f6)
Reviewed-on: http://git-master/r/396898
Reviewed-by: Preetham Chandru <pchandru@nvidia.com>
Tested-by: Preetham Chandru <pchandru@nvidia.com>
Reviewed-by: Bitan Biswas <bbiswas@nvidia.com>

1 files changed, 39 insertions, 2 deletions

diff --git a/drivers/net/usb/r8152_shield.c b/drivers/net/usb/r8152_shield.c
index 9c3ca4c38..571a2af3c 100644
--- a/drivers/net/usb/r8152_shield.c
+++ b/drivers/net/usb/r8152_shield.c
@@ -465,8 +465,17 @@ enum rtl8152_flags {
 struct rx_desc {
         __le32 opts1;
 #define RX_LEN_MASK                     0x7fff
+
         __le32 opts2;
+#define RD_UDP_CS                       (1 << 23)
+#define RD_TCP_CS                       (1 << 22)
+#define RD_IPV4_CS                      (1 << 19)
+
         __le32 opts3;
+#define IPF                             (1 << 23) /* IP checksum fail */
+#define UDPF                            (1 << 22) /* UDP checksum fail */
+#define TCPF                            (1 << 21) /* TCP checksum fail */
+
         __le32 opts4;
         __le32 opts5;
         __le32 opts6;
@@ -1402,6 +1411,32 @@ out_tx_fill:
         return ret;
 }
 
+static u8 r8152_rx_csum(struct r8152 *tp, struct rx_desc *rx_desc)
+{
+        u8 checksum = CHECKSUM_NONE;
+        u32 opts2, opts3;
+
+        if (tp->version == RTL_VER_01)
+                goto return_result;
+
+        opts2 = le32_to_cpu(rx_desc->opts2);
+        opts3 = le32_to_cpu(rx_desc->opts3);
+
+        if (opts2 & RD_IPV4_CS) {
+                if (opts3 & IPF)
+                        checksum = CHECKSUM_NONE;
+                else if ((opts2 & RD_UDP_CS) && (opts3 & UDPF))
+                        checksum = CHECKSUM_NONE;
+                else if ((opts2 & RD_TCP_CS) && (opts3 & TCPF))
+                        checksum = CHECKSUM_NONE;
+                else
+                        checksum = CHECKSUM_UNNECESSARY;
+        }
+
+return_result:
+        return checksum;
+}
+
 static void rx_bottom(struct r8152 *tp)
 {
         unsigned long flags;
@@ -1456,6 +1491,8 @@ static void rx_bottom(struct r8152 *tp)
                                 stats->rx_dropped++;
                                 goto find_next_rx;
                         }
+
+                        skb->ip_summed = r8152_rx_csum(tp, rx_desc);
                         memcpy(skb->data, rx_data, pkt_len);
                         skb_put(skb, pkt_len);
                         skb->protocol = eth_type_trans(skb, netdev);
@@ -3106,8 +3143,8 @@ static int rtl8152_probe(struct usb_interface *intf,
         netdev->netdev_ops = &rtl8152_netdev_ops;
         netdev->watchdog_timeo = RTL8152_TX_TIMEOUT;
 
-        netdev->features |= NETIF_F_IP_CSUM;
-        netdev->hw_features = NETIF_F_IP_CSUM;
+        netdev->features |= NETIF_F_RXCSUM | NETIF_F_IP_CSUM;
+        netdev->hw_features = NETIF_F_RXCSUM | NETIF_F_IP_CSUM;
 
         SET_ETHTOOL_OPS(netdev, &ops);