nfp: support TX VLAN ctag insert

Add support for TX VLAN ctag insert
which may be configured via ethtool.

e.g.
     # ethtool -K $DEV tx-vlan-offload on

The NIC supplies VLAN insert information as packet metadata.
The fields of this VLAN metadata are gotten from sk_buff, including
vlan_proto and vlan tag.

Configuration control bit NFP_NET_CFG_CTRL_TXVLAN_V2 is to
signal availability of ctag-insert features of the firmware.

NFDK is used to communicate via PCIE to NFP-3800 based NICs
while NFD3 is used for other NICs supported by the NFP driver.
The metadata format on tx side of NFD3 is different from NFDK.
This feature is not currently implemented for NFDK.

Signed-off-by: Diana Wang <na.wang@corigine.com>
Reviewed-by: Louis Peens <louis.peens@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/nfd3/dp.c

@@ -167,44 +167,59 @@ nfp_nfd3_tx_csum(struct nfp_net_dp *dp, struct nfp_net_r_vector *r_vec,
 	u64_stats_update_end(&r_vec->tx_sync);
 }
 
-static int nfp_nfd3_prep_tx_meta(struct sk_buff *skb, u64 tls_handle)
+static int nfp_nfd3_prep_tx_meta(struct nfp_net_dp *dp, struct sk_buff *skb, u64 tls_handle)
 {
 	struct metadata_dst *md_dst = skb_metadata_dst(skb);
 	unsigned char *data;
+	bool vlan_insert;
 	u32 meta_id = 0;
 	int md_bytes;
 
-	if (likely(!md_dst && !tls_handle))
-		return 0;
-	if (unlikely(md_dst && md_dst->type != METADATA_HW_PORT_MUX)) {
-		if (!tls_handle)
-			return 0;
-		md_dst = NULL;
+	if (unlikely(md_dst || tls_handle)) {
+		if (unlikely(md_dst && md_dst->type != METADATA_HW_PORT_MUX))
+			md_dst = NULL;
 	}
 
-	md_bytes = 4 + !!md_dst * 4 + !!tls_handle * 8;
+	vlan_insert = skb_vlan_tag_present(skb) && (dp->ctrl & NFP_NET_CFG_CTRL_TXVLAN_V2);
+
+	if (!(md_dst || tls_handle || vlan_insert))
+		return 0;
+
+	md_bytes = sizeof(meta_id) +
+		   !!md_dst * NFP_NET_META_PORTID_SIZE +
+		   !!tls_handle * NFP_NET_META_CONN_HANDLE_SIZE +
+		   vlan_insert * NFP_NET_META_VLAN_SIZE;
 
 	if (unlikely(skb_cow_head(skb, md_bytes)))
 		return -ENOMEM;
 
-	meta_id = 0;
 	data = skb_push(skb, md_bytes) + md_bytes;
 	if (md_dst) {
-		data -= 4;
+		data -= NFP_NET_META_PORTID_SIZE;
 		put_unaligned_be32(md_dst->u.port_info.port_id, data);
 		meta_id = NFP_NET_META_PORTID;
 	}
 	if (tls_handle) {
 		/* conn handle is opaque, we just use u64 to be able to quickly
 		 * compare it to zero
 		 */
-		data -= 8;
+		data -= NFP_NET_META_CONN_HANDLE_SIZE;
 		memcpy(data, &tls_handle, sizeof(tls_handle));
 		meta_id <<= NFP_NET_META_FIELD_SIZE;
 		meta_id |= NFP_NET_META_CONN_HANDLE;
 	}
+	if (vlan_insert) {
+		data -= NFP_NET_META_VLAN_SIZE;
+		/* data type of skb->vlan_proto is __be16
+		 * so it fills metadata without calling put_unaligned_be16
+		 */
+		memcpy(data, &skb->vlan_proto, sizeof(skb->vlan_proto));
+		put_unaligned_be16(skb_vlan_tag_get(skb), data + sizeof(skb->vlan_proto));
+		meta_id <<= NFP_NET_META_FIELD_SIZE;
+		meta_id |= NFP_NET_META_VLAN;
+	}
 
-	data -= 4;
+	data -= sizeof(meta_id);
 	put_unaligned_be32(meta_id, data);
 
 	return md_bytes;
@@ -258,7 +273,7 @@ netdev_tx_t nfp_nfd3_tx(struct sk_buff *skb, struct net_device *netdev)
 		return NETDEV_TX_OK;
 	}
 
-	md_bytes = nfp_nfd3_prep_tx_meta(skb, tls_handle);
+	md_bytes = nfp_nfd3_prep_tx_meta(dp, skb, tls_handle);
 	if (unlikely(md_bytes < 0))
 		goto err_flush;
 

drivers/net/ethernet/netronome/nfp/nfd3/rings.c

@@ -248,6 +248,7 @@ nfp_nfd3_print_tx_descs(struct seq_file *file,
 	 NFP_NET_CFG_CTRL_RXCSUM | NFP_NET_CFG_CTRL_TXCSUM |		\
 	 NFP_NET_CFG_CTRL_RXVLAN | NFP_NET_CFG_CTRL_TXVLAN |		\
 	 NFP_NET_CFG_CTRL_RXVLAN_V2 | NFP_NET_CFG_CTRL_RXQINQ |		\
+	 NFP_NET_CFG_CTRL_TXVLAN_V2 |					\
 	 NFP_NET_CFG_CTRL_GATHER | NFP_NET_CFG_CTRL_LSO |		\
 	 NFP_NET_CFG_CTRL_CTAG_FILTER | NFP_NET_CFG_CTRL_CMSG_DATA |	\
 	 NFP_NET_CFG_CTRL_RINGCFG | NFP_NET_CFG_CTRL_RSS |		\

drivers/net/ethernet/netronome/nfp/nfp_net_common.c

@@ -1703,9 +1703,10 @@ static int nfp_net_set_features(struct net_device *netdev,
 
 	if (changed & NETIF_F_HW_VLAN_CTAG_TX) {
 		if (features & NETIF_F_HW_VLAN_CTAG_TX)
-			new_ctrl |= NFP_NET_CFG_CTRL_TXVLAN;
+			new_ctrl |= nn->cap & NFP_NET_CFG_CTRL_TXVLAN_V2 ?:
+				    NFP_NET_CFG_CTRL_TXVLAN;
 		else
-			new_ctrl &= ~NFP_NET_CFG_CTRL_TXVLAN;
+			new_ctrl &= ~NFP_NET_CFG_CTRL_TXVLAN_ANY;
 	}
 
 	if (changed & NETIF_F_HW_VLAN_CTAG_FILTER) {
@@ -2092,7 +2093,7 @@ void nfp_net_info(struct nfp_net *nn)
 		nn->fw_ver.extend, nn->fw_ver.class,
 		nn->fw_ver.major, nn->fw_ver.minor,
 		nn->max_mtu);
-	nn_info(nn, "CAP: %#x %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n",
+	nn_info(nn, "CAP: %#x %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n",
 		nn->cap,
 		nn->cap & NFP_NET_CFG_CTRL_PROMISC  ? "PROMISC "  : "",
 		nn->cap & NFP_NET_CFG_CTRL_L2BC     ? "L2BCFILT " : "",
@@ -2103,6 +2104,7 @@ void nfp_net_info(struct nfp_net *nn)
 		nn->cap & NFP_NET_CFG_CTRL_TXVLAN   ? "TXVLAN "   : "",
 		nn->cap & NFP_NET_CFG_CTRL_RXQINQ   ? "RXQINQ "   : "",
 		nn->cap & NFP_NET_CFG_CTRL_RXVLAN_V2 ? "RXVLANv2 "   : "",
+		nn->cap & NFP_NET_CFG_CTRL_TXVLAN_V2   ? "TXVLAN2 "   : "",
 		nn->cap & NFP_NET_CFG_CTRL_SCATTER  ? "SCATTER "  : "",
 		nn->cap & NFP_NET_CFG_CTRL_GATHER   ? "GATHER "   : "",
 		nn->cap & NFP_NET_CFG_CTRL_LSO      ? "TSO1 "     : "",
@@ -2395,12 +2397,13 @@ static void nfp_net_netdev_init(struct nfp_net *nn)
 		nn->dp.ctrl |= nn->cap & NFP_NET_CFG_CTRL_RXVLAN_V2 ?:
 			       NFP_NET_CFG_CTRL_RXVLAN;
 	}
-	if (nn->cap & NFP_NET_CFG_CTRL_TXVLAN) {
+	if (nn->cap & NFP_NET_CFG_CTRL_TXVLAN_ANY) {
 		if (nn->cap & NFP_NET_CFG_CTRL_LSO2) {
 			nn_warn(nn, "Device advertises both TSO2 and TXVLAN. Refusing to enable TXVLAN.\n");
 		} else {
 			netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_TX;
-			nn->dp.ctrl |= NFP_NET_CFG_CTRL_TXVLAN;
+			nn->dp.ctrl |= nn->cap & NFP_NET_CFG_CTRL_TXVLAN_V2 ?:
+				       NFP_NET_CFG_CTRL_TXVLAN;
 		}
 	}
 	if (nn->cap & NFP_NET_CFG_CTRL_CTAG_FILTER) {

drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h

@@ -48,6 +48,10 @@
 
 #define NFP_META_PORT_ID_CTRL		~0U
 
+/* Prepend field sizes */
+#define NFP_NET_META_VLAN_SIZE			4
+#define NFP_NET_META_PORTID_SIZE		4
+#define NFP_NET_META_CONN_HANDLE_SIZE		8
 /* Hash type pre-pended when a RSS hash was computed */
 #define NFP_NET_RSS_NONE		0
 #define NFP_NET_RSS_IPV4		1
@@ -103,6 +107,7 @@
 #define   NFP_NET_CFG_CTRL_MSIXAUTO	  (0x1 << 20) /* MSI-X auto-masking */
 #define   NFP_NET_CFG_CTRL_TXRWB	  (0x1 << 21) /* Write-back of TX ring*/
 #define   NFP_NET_CFG_CTRL_VEPA		  (0x1 << 22) /* Enable VEPA mode */
+#define   NFP_NET_CFG_CTRL_TXVLAN_V2	  (0x1 << 23) /* Enable VLAN C-tag insert*/
 #define   NFP_NET_CFG_CTRL_VXLAN	  (0x1 << 24) /* VXLAN tunnel support */
 #define   NFP_NET_CFG_CTRL_NVGRE	  (0x1 << 25) /* NVGRE tunnel support */
 #define   NFP_NET_CFG_CTRL_BPF		  (0x1 << 27) /* BPF offload capable */
@@ -121,6 +126,8 @@
 					 NFP_NET_CFG_CTRL_CSUM_COMPLETE)
 #define NFP_NET_CFG_CTRL_RXVLAN_ANY	(NFP_NET_CFG_CTRL_RXVLAN | \
 					 NFP_NET_CFG_CTRL_RXVLAN_V2)
+#define NFP_NET_CFG_CTRL_TXVLAN_ANY	(NFP_NET_CFG_CTRL_TXVLAN | \
+					 NFP_NET_CFG_CTRL_TXVLAN_V2)
 
 #define NFP_NET_CFG_UPDATE		0x0004
 #define   NFP_NET_CFG_UPDATE_GEN	  (0x1 <<  0) /* General update */

drivers/net/ethernet/netronome/nfp/nfp_net_repr.c

@@ -367,7 +367,7 @@ int nfp_repr_init(struct nfp_app *app, struct net_device *netdev,
 
 	if (repr_cap & NFP_NET_CFG_CTRL_RXVLAN_ANY)
 		netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_RX;
-	if (repr_cap & NFP_NET_CFG_CTRL_TXVLAN) {
+	if (repr_cap & NFP_NET_CFG_CTRL_TXVLAN_ANY) {
 		if (repr_cap & NFP_NET_CFG_CTRL_LSO2)
 			netdev_warn(netdev, "Device advertises both TSO2 and TXVLAN. Refusing to enable TXVLAN.\n");
 		else