nfp: support RX VLAN ctag/stag strip

Add support for RX VLAN ctag/stag strip
which may be configured via ethtool.

e.g.
     # ethtool -K $DEV rx-vlan-offload on
     # ethtool -K $DEV rx-vlan-stag-hw-parse on

Ctag-stripped and stag-stripped cannot be enabled at the same time
because currently the kernel supports only one layer of VLAN stripping.

The NIC supplies VLAN strip information as packet metadata.
The fields of this VLAN metadata are:

* strip flag: 1 for stripped; 0 for unstripped
* tci: VLAN TCI ID
* tpid: 1 for ETH_P_8021AD; 0 for ETH_P_8021Q

Configuration control bits NFP_NET_CFG_CTRL_RXVLAN_V2 and
NFP_NET_CFG_CTRL_RXQINQ are to signal availability of
ctag-strip and stag-strip features of the firmware.
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

@@ -3,6 +3,7 @@
 
 #include <linux/bpf_trace.h>
 #include <linux/netdevice.h>
+#include <linux/bitfield.h>
 
 #include "../nfp_app.h"
 #include "../nfp_net.h"
@@ -703,7 +704,7 @@ bool
 nfp_nfd3_parse_meta(struct net_device *netdev, struct nfp_meta_parsed *meta,
 		    void *data, void *pkt, unsigned int pkt_len, int meta_len)
 {
-	u32 meta_info;
+	u32 meta_info, vlan_info;
 
 	meta_info = get_unaligned_be32(data);
 	data += 4;
@@ -721,6 +722,17 @@ nfp_nfd3_parse_meta(struct net_device *netdev, struct nfp_meta_parsed *meta,
 			meta->mark = get_unaligned_be32(data);
 			data += 4;
 			break;
+		case NFP_NET_META_VLAN:
+			vlan_info = get_unaligned_be32(data);
+			if (FIELD_GET(NFP_NET_META_VLAN_STRIP, vlan_info)) {
+				meta->vlan.stripped = true;
+				meta->vlan.tpid = FIELD_GET(NFP_NET_META_VLAN_TPID_MASK,
+							    vlan_info);
+				meta->vlan.tci = FIELD_GET(NFP_NET_META_VLAN_TCI_MASK,
+							   vlan_info);
+			}
+			data += 4;
+			break;
 		case NFP_NET_META_PORTID:
 			meta->portid = get_unaligned_be32(data);
 			data += 4;
@@ -1049,9 +1061,11 @@ static int nfp_nfd3_rx(struct nfp_net_rx_ring *rx_ring, int budget)
 		}
 #endif
 
-		if (rxd->rxd.flags & PCIE_DESC_RX_VLAN)
-			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
-					       le16_to_cpu(rxd->rxd.vlan));
+		if (unlikely(!nfp_net_vlan_strip(skb, rxd, &meta))) {
+			nfp_nfd3_rx_drop(dp, r_vec, rx_ring, NULL, skb);
+			continue;
+		}
+
 		if (meta_len_xdp)
 			skb_metadata_set(skb, meta_len_xdp);
 

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

@@ -247,6 +247,7 @@ nfp_nfd3_print_tx_descs(struct seq_file *file,
 	 NFP_NET_CFG_CTRL_L2BC | NFP_NET_CFG_CTRL_L2MC |		\
 	 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_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/nfd3/xsk.c

@@ -94,9 +94,12 @@ static void nfp_nfd3_xsk_rx_skb(struct nfp_net_rx_ring *rx_ring,
 
 	nfp_nfd3_rx_csum(dp, r_vec, rxd, meta, skb);
 
-	if (rxd->rxd.flags & PCIE_DESC_RX_VLAN)
-		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
-				       le16_to_cpu(rxd->rxd.vlan));
+	if (unlikely(!nfp_net_vlan_strip(skb, rxd, meta))) {
+		dev_kfree_skb_any(skb);
+		nfp_net_xsk_rx_drop(r_vec, xrxbuf);
+		return;
+	}
+
 	if (meta_xdp)
 		skb_metadata_set(skb,
 				 xrxbuf->xdp->data - xrxbuf->xdp->data_meta);

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

@@ -716,7 +716,7 @@ static bool
 nfp_nfdk_parse_meta(struct net_device *netdev, struct nfp_meta_parsed *meta,
 		    void *data, void *pkt, unsigned int pkt_len, int meta_len)
 {
-	u32 meta_info;
+	u32 meta_info, vlan_info;
 
 	meta_info = get_unaligned_be32(data);
 	data += 4;
@@ -734,6 +734,17 @@ nfp_nfdk_parse_meta(struct net_device *netdev, struct nfp_meta_parsed *meta,
 			meta->mark = get_unaligned_be32(data);
 			data += 4;
 			break;
+		case NFP_NET_META_VLAN:
+			vlan_info = get_unaligned_be32(data);
+			if (FIELD_GET(NFP_NET_META_VLAN_STRIP, vlan_info)) {
+				meta->vlan.stripped = true;
+				meta->vlan.tpid = FIELD_GET(NFP_NET_META_VLAN_TPID_MASK,
+							    vlan_info);
+				meta->vlan.tci = FIELD_GET(NFP_NET_META_VLAN_TCI_MASK,
+							   vlan_info);
+			}
+			data += 4;
+			break;
 		case NFP_NET_META_PORTID:
 			meta->portid = get_unaligned_be32(data);
 			data += 4;
@@ -1169,9 +1180,11 @@ static int nfp_nfdk_rx(struct nfp_net_rx_ring *rx_ring, int budget)
 
 		nfp_nfdk_rx_csum(dp, r_vec, rxd, &meta, skb);
 
-		if (rxd->rxd.flags & PCIE_DESC_RX_VLAN)
-			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
-					       le16_to_cpu(rxd->rxd.vlan));
+		if (unlikely(!nfp_net_vlan_strip(skb, rxd, &meta))) {
+			nfp_nfdk_rx_drop(dp, r_vec, rx_ring, NULL, skb);
+			continue;
+		}
+
 		if (meta_len_xdp)
 			skb_metadata_set(skb, meta_len_xdp);
 

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

@@ -168,6 +168,7 @@ nfp_nfdk_print_tx_descs(struct seq_file *file,
 	 NFP_NET_CFG_CTRL_L2BC | NFP_NET_CFG_CTRL_L2MC |		\
 	 NFP_NET_CFG_CTRL_RXCSUM | NFP_NET_CFG_CTRL_TXCSUM |		\
 	 NFP_NET_CFG_CTRL_RXVLAN |					\
+	 NFP_NET_CFG_CTRL_RXVLAN_V2 | NFP_NET_CFG_CTRL_RXQINQ |		\
 	 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_IRQMOD |		\

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

@@ -248,6 +248,8 @@ struct nfp_net_rx_desc {
 };
 
 #define NFP_NET_META_FIELD_MASK GENMASK(NFP_NET_META_FIELD_SIZE - 1, 0)
+#define NFP_NET_VLAN_CTAG	0
+#define NFP_NET_VLAN_STAG	1
 
 struct nfp_meta_parsed {
 	u8 hash_type;
@@ -256,6 +258,11 @@ struct nfp_meta_parsed {
 	u32 mark;
 	u32 portid;
 	__wsum csum;
+	struct {
+		bool stripped;
+		u8 tpid;
+		u16 tci;
+	} vlan;
 };
 
 struct nfp_net_rx_hash {

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

@@ -1695,9 +1695,10 @@ static int nfp_net_set_features(struct net_device *netdev,
 
 	if (changed & NETIF_F_HW_VLAN_CTAG_RX) {
 		if (features & NETIF_F_HW_VLAN_CTAG_RX)
-			new_ctrl |= NFP_NET_CFG_CTRL_RXVLAN;
+			new_ctrl |= nn->cap & NFP_NET_CFG_CTRL_RXVLAN_V2 ?:
+				    NFP_NET_CFG_CTRL_RXVLAN;
 		else
-			new_ctrl &= ~NFP_NET_CFG_CTRL_RXVLAN;
+			new_ctrl &= ~NFP_NET_CFG_CTRL_RXVLAN_ANY;
 	}
 
 	if (changed & NETIF_F_HW_VLAN_CTAG_TX) {
@@ -1714,6 +1715,13 @@ static int nfp_net_set_features(struct net_device *netdev,
 			new_ctrl &= ~NFP_NET_CFG_CTRL_CTAG_FILTER;
 	}
 
+	if (changed & NETIF_F_HW_VLAN_STAG_RX) {
+		if (features & NETIF_F_HW_VLAN_STAG_RX)
+			new_ctrl |= NFP_NET_CFG_CTRL_RXQINQ;
+		else
+			new_ctrl &= ~NFP_NET_CFG_CTRL_RXQINQ;
+	}
+
 	if (changed & NETIF_F_SG) {
 		if (features & NETIF_F_SG)
 			new_ctrl |= NFP_NET_CFG_CTRL_GATHER;
@@ -1742,6 +1750,27 @@ static int nfp_net_set_features(struct net_device *netdev,
 	return 0;
 }
 
+static netdev_features_t
+nfp_net_fix_features(struct net_device *netdev,
+		     netdev_features_t features)
+{
+	if ((features & NETIF_F_HW_VLAN_CTAG_RX) &&
+	    (features & NETIF_F_HW_VLAN_STAG_RX)) {
+		if (netdev->features & NETIF_F_HW_VLAN_CTAG_RX) {
+			features &= ~NETIF_F_HW_VLAN_CTAG_RX;
+			netdev->wanted_features &= ~NETIF_F_HW_VLAN_CTAG_RX;
+			netdev_warn(netdev,
+				    "S-tag and C-tag stripping can't be enabled at the same time. Enabling S-tag stripping and disabling C-tag stripping\n");
+		} else if (netdev->features & NETIF_F_HW_VLAN_STAG_RX) {
+			features &= ~NETIF_F_HW_VLAN_STAG_RX;
+			netdev->wanted_features &= ~NETIF_F_HW_VLAN_STAG_RX;
+			netdev_warn(netdev,
+				    "S-tag and C-tag stripping can't be enabled at the same time. Enabling C-tag stripping and disabling S-tag stripping\n");
+		}
+	}
+	return features;
+}
+
 static netdev_features_t
 nfp_net_features_check(struct sk_buff *skb, struct net_device *dev,
 		       netdev_features_t features)
@@ -1977,6 +2006,7 @@ const struct net_device_ops nfp_nfd3_netdev_ops = {
 	.ndo_change_mtu		= nfp_net_change_mtu,
 	.ndo_set_mac_address	= nfp_net_set_mac_address,
 	.ndo_set_features	= nfp_net_set_features,
+	.ndo_fix_features	= nfp_net_fix_features,
 	.ndo_features_check	= nfp_net_features_check,
 	.ndo_get_phys_port_name	= nfp_net_get_phys_port_name,
 	.ndo_bpf		= nfp_net_xdp,
@@ -2008,6 +2038,7 @@ const struct net_device_ops nfp_nfdk_netdev_ops = {
 	.ndo_change_mtu		= nfp_net_change_mtu,
 	.ndo_set_mac_address	= nfp_net_set_mac_address,
 	.ndo_set_features	= nfp_net_set_features,
+	.ndo_fix_features	= nfp_net_fix_features,
 	.ndo_features_check	= nfp_net_features_check,
 	.ndo_get_phys_port_name	= nfp_net_get_phys_port_name,
 	.ndo_bpf		= nfp_net_xdp,
@@ -2061,7 +2092,7 @@ 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\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\n",
 		nn->cap,
 		nn->cap & NFP_NET_CFG_CTRL_PROMISC  ? "PROMISC "  : "",
 		nn->cap & NFP_NET_CFG_CTRL_L2BC     ? "L2BCFILT " : "",
@@ -2070,6 +2101,8 @@ void nfp_net_info(struct nfp_net *nn)
 		nn->cap & NFP_NET_CFG_CTRL_TXCSUM   ? "TXCSUM "   : "",
 		nn->cap & NFP_NET_CFG_CTRL_RXVLAN   ? "RXVLAN "   : "",
 		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_SCATTER  ? "SCATTER "  : "",
 		nn->cap & NFP_NET_CFG_CTRL_GATHER   ? "GATHER "   : "",
 		nn->cap & NFP_NET_CFG_CTRL_LSO      ? "TSO1 "     : "",
@@ -2357,9 +2390,10 @@ static void nfp_net_netdev_init(struct nfp_net *nn)
 
 	netdev->vlan_features = netdev->hw_features;
 
-	if (nn->cap & NFP_NET_CFG_CTRL_RXVLAN) {
+	if (nn->cap & NFP_NET_CFG_CTRL_RXVLAN_ANY) {
 		netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_RX;
-		nn->dp.ctrl |= NFP_NET_CFG_CTRL_RXVLAN;
+		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_LSO2) {
@@ -2373,15 +2407,22 @@ static void nfp_net_netdev_init(struct nfp_net *nn)
 		netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_FILTER;
 		nn->dp.ctrl |= NFP_NET_CFG_CTRL_CTAG_FILTER;
 	}
+	if (nn->cap & NFP_NET_CFG_CTRL_RXQINQ) {
+		netdev->hw_features |= NETIF_F_HW_VLAN_STAG_RX;
+		nn->dp.ctrl |= NFP_NET_CFG_CTRL_RXQINQ;
+	}
 
 	netdev->features = netdev->hw_features;
 
 	if (nfp_app_has_tc(nn->app) && nn->port)
 		netdev->hw_features |= NETIF_F_HW_TC;
 
-	/* Advertise but disable TSO by default. */
-	netdev->features &= ~(NETIF_F_TSO | NETIF_F_TSO6);
-	nn->dp.ctrl &= ~NFP_NET_CFG_CTRL_LSO_ANY;
+	/* Advertise but disable TSO by default.
+	 * C-Tag strip and S-Tag strip can't be supported simultaneously,
+	 * so enable C-Tag strip and disable S-Tag strip by default.
+	 */
+	netdev->features &= ~(NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_HW_VLAN_STAG_RX);
+	nn->dp.ctrl &= ~(NFP_NET_CFG_CTRL_LSO_ANY | NFP_NET_CFG_CTRL_RXQINQ);
 
 	/* Finalise the netdev setup */
 	switch (nn->dp.ops->version) {

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

@@ -31,10 +31,16 @@
 #define NFP_NET_LSO_MAX_HDR_SZ		255
 #define NFP_NET_LSO_MAX_SEGS		64
 
+/* working with metadata vlan api (NFD version >= 2.0) */
+#define NFP_NET_META_VLAN_STRIP			BIT(31)
+#define NFP_NET_META_VLAN_TPID_MASK		GENMASK(19, 16)
+#define NFP_NET_META_VLAN_TCI_MASK		GENMASK(15, 0)
+
 /* Prepend field types */
 #define NFP_NET_META_FIELD_SIZE		4
 #define NFP_NET_META_HASH		1 /* next field carries hash type */
 #define NFP_NET_META_MARK		2
+#define NFP_NET_META_VLAN		4 /* ctag or stag type */
 #define NFP_NET_META_PORTID		5
 #define NFP_NET_META_CSUM		6 /* checksum complete type */
 #define NFP_NET_META_CONN_HANDLE	7
@@ -89,6 +95,8 @@
 #define   NFP_NET_CFG_CTRL_LSO		  (0x1 << 10) /* LSO/TSO (version 1) */
 #define   NFP_NET_CFG_CTRL_CTAG_FILTER	  (0x1 << 11) /* VLAN CTAG filtering */
 #define   NFP_NET_CFG_CTRL_CMSG_DATA	  (0x1 << 12) /* RX cmsgs on data Qs */
+#define   NFP_NET_CFG_CTRL_RXQINQ	  (0x1 << 13) /* Enable S-tag strip */
+#define   NFP_NET_CFG_CTRL_RXVLAN_V2	  (0x1 << 15) /* Enable C-tag strip */
 #define   NFP_NET_CFG_CTRL_RINGCFG	  (0x1 << 16) /* Ring runtime changes */
 #define   NFP_NET_CFG_CTRL_RSS		  (0x1 << 17) /* RSS (version 1) */
 #define   NFP_NET_CFG_CTRL_IRQMOD	  (0x1 << 18) /* Interrupt moderation */
@@ -111,6 +119,8 @@
 					 NFP_NET_CFG_CTRL_CSUM_COMPLETE)
 #define NFP_NET_CFG_CTRL_CHAIN_META	(NFP_NET_CFG_CTRL_RSS2 | \
 					 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_UPDATE		0x0004
 #define   NFP_NET_CFG_UPDATE_GEN	  (0x1 <<  0) /* General update */

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

@@ -440,3 +440,27 @@ bool nfp_ctrl_tx(struct nfp_net *nn, struct sk_buff *skb)
 
 	return ret;
 }
+
+bool nfp_net_vlan_strip(struct sk_buff *skb, const struct nfp_net_rx_desc *rxd,
+			const struct nfp_meta_parsed *meta)
+{
+	u16 tpid = 0, tci = 0;
+
+	if (rxd->rxd.flags & PCIE_DESC_RX_VLAN) {
+		tpid = ETH_P_8021Q;
+		tci = le16_to_cpu(rxd->rxd.vlan);
+	} else if (meta->vlan.stripped) {
+		if (meta->vlan.tpid == NFP_NET_VLAN_CTAG)
+			tpid = ETH_P_8021Q;
+		else if (meta->vlan.tpid == NFP_NET_VLAN_STAG)
+			tpid = ETH_P_8021AD;
+		else
+			return false;
+
+		tci = meta->vlan.tci;
+	}
+	if (tpid)
+		__vlan_hwaccel_put_tag(skb, htons(tpid), tci);
+
+	return true;
+}

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

@@ -106,6 +106,8 @@ int nfp_net_tx_rings_prepare(struct nfp_net *nn, struct nfp_net_dp *dp);
 void nfp_net_rx_rings_free(struct nfp_net_dp *dp);
 void nfp_net_tx_rings_free(struct nfp_net_dp *dp);
 void nfp_net_rx_ring_reset(struct nfp_net_rx_ring *rx_ring);
+bool nfp_net_vlan_strip(struct sk_buff *skb, const struct nfp_net_rx_desc *rxd,
+			const struct nfp_meta_parsed *meta);
 
 enum nfp_nfd_version {
 	NFP_NFD_VER_NFD3,

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

@@ -365,7 +365,7 @@ int nfp_repr_init(struct nfp_app *app, struct net_device *netdev,
 
 	netdev->vlan_features = netdev->hw_features;
 
-	if (repr_cap & NFP_NET_CFG_CTRL_RXVLAN)
+	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_LSO2)
@@ -375,11 +375,16 @@ int nfp_repr_init(struct nfp_app *app, struct net_device *netdev,
 	}
 	if (repr_cap & NFP_NET_CFG_CTRL_CTAG_FILTER)
 		netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_FILTER;
+	if (repr_cap & NFP_NET_CFG_CTRL_RXQINQ)
+		netdev->hw_features |= NETIF_F_HW_VLAN_STAG_RX;
 
 	netdev->features = netdev->hw_features;
 
-	/* Advertise but disable TSO by default. */
-	netdev->features &= ~(NETIF_F_TSO | NETIF_F_TSO6);
+	/* Advertise but disable TSO by default.
+	 * C-Tag strip and S-Tag strip can't be supported simultaneously,
+	 * so enable C-Tag strip and disable S-Tag strip by default.
+	 */
+	netdev->features &= ~(NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_HW_VLAN_STAG_RX);
 	netif_set_tso_max_segs(netdev, NFP_NET_LSO_MAX_SEGS);
 
 	netdev->priv_flags |= IFF_NO_QUEUE | IFF_DISABLE_NETPOLL;