net: ravb: Add VLAN checksum support

The GbEth IP supports offloading checksum calculation for VLAN-tagged
packets, provided that the EtherType is 0x8100 and only one VLAN tag is
present.

Signed-off-by: Paul Barker <paul.barker.ct@bp.renesas.com>
Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>

diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h
index d7b3810ce21b46adb77031a799fa79bdd78e2cae..7b48060c250b4b274d6ce7c10e303854de18f6ff 100644 (file)
--- a/drivers/net/ethernet/renesas/ravb.h
+++ b/drivers/net/ethernet/renesas/ravb.h
@@ -1055,6 +1055,7 @@ struct ravb_hw_info {
        size_t gstrings_size;
        netdev_features_t net_hw_features;
        netdev_features_t net_features;
+       netdev_features_t vlan_features;
        int stats_len;
        u32 tccr_mask;
        u32 tx_max_frame_size;

diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index 14b4462331b0796a186d8acf175ccb89b2855944..bc56f1f4bec929d894a33286b775c157773f533d 100644 (file)
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -2063,13 +2063,27 @@ out_unlock:
 
 static bool ravb_can_tx_csum_gbeth(struct sk_buff *skb)
 {
+       u16 net_protocol = ntohs(skb->protocol);
        u8 inner_protocol;
 
-       /* TODO: Need to add support for VLAN tag 802.1Q */
-       if (skb_vlan_tag_present(skb))
-               return false;
+       /* GbEth IP can calculate the checksum if:
+        * - there are zero or one VLAN headers with TPID=0x8100
+        * - the network protocol is IPv4 or IPv6
+        * - the transport protocol is TCP, UDP or ICMP
+        * - the packet is not fragmented
+        */
+
+       if (net_protocol == ETH_P_8021Q) {
+               struct vlan_hdr vhdr, *vh;
+
+               vh = skb_header_pointer(skb, ETH_HLEN, sizeof(vhdr), &vhdr);
+               if (!vh)
+                       return false;
+
+               net_protocol = ntohs(vh->h_vlan_encapsulated_proto);
+       }
 
-       switch (ntohs(skb->protocol)) {
+       switch (net_protocol) {
        case ETH_P_IP:
                inner_protocol = ip_hdr(skb)->protocol;
                break;
@@ -2772,6 +2786,7 @@ static const struct ravb_hw_info gbeth_hw_info = {
        .gstrings_size = sizeof(ravb_gstrings_stats_gbeth),
        .net_hw_features = NETIF_F_RXCSUM | NETIF_F_HW_CSUM,
        .net_features = NETIF_F_RXCSUM | NETIF_F_HW_CSUM,
+       .vlan_features = NETIF_F_RXCSUM | NETIF_F_HW_CSUM,
        .stats_len = ARRAY_SIZE(ravb_gstrings_stats_gbeth),
        .tccr_mask = TCCR_TSRQ0,
        .tx_max_frame_size = 1522,
@@ -2914,6 +2929,7 @@ static int ravb_probe(struct platform_device *pdev)
 
        ndev->features = info->net_features;
        ndev->hw_features = info->net_hw_features;
+       ndev->vlan_features = info->vlan_features;
 
        error = reset_control_deassert(rstc);
        if (error)