1 files changed, 102 insertions, 0 deletions
diff --git a/net/dsa/tag_ocelot_8021q.c b/net/dsa/tag_ocelot_8021q.c
new file mode 100644
index 000000000000..5f3e8e124a82
--- /dev/null
+++ b/net/dsa/tag_ocelot_8021q.c
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2020-2021 NXP Semiconductors
+ *
+ * An implementation of the software-defined tag_8021q.c tagger format, which
+ * also preserves full functionality under a vlan_filtering bridge. It does
+ * this by using the TCAM engines for:
+ * - pushing the RX VLAN as a second, outer tag, on egress towards the CPU port
+ * - redirecting towards the correct front port based on TX VLAN and popping
+ *   that on egress
+ */
+#include <linux/dsa/8021q.h>
+#include <soc/mscc/ocelot.h>
+#include <soc/mscc/ocelot_ptp.h>
+#include "dsa_priv.h"
+
+static struct sk_buff *ocelot_xmit_ptp(struct dsa_port *dp,
+				       struct sk_buff *skb,
+				       struct sk_buff *clone)
+{
+	struct ocelot *ocelot = dp->ds->priv;
+	struct ocelot_port *ocelot_port;
+	int port = dp->index;
+	u32 rew_op;
+
+	if (!ocelot_can_inject(ocelot, 0))
+		return NULL;
+
+	ocelot_port = ocelot->ports[port];
+	rew_op = ocelot_port->ptp_cmd;
+
+	/* Retrieve timestamp ID populated inside skb->cb[0] of the
+	 * clone by ocelot_port_add_txtstamp_skb
+	 */
+	if (ocelot_port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP)
+		rew_op |= clone->cb[0] << 3;
+
+	ocelot_port_inject_frame(ocelot, port, 0, rew_op, skb);
+
+	return NULL;
+}
+
+static struct sk_buff *ocelot_xmit(struct sk_buff *skb,
+				   struct net_device *netdev)
+{
+	struct dsa_port *dp = dsa_slave_to_port(netdev);
+	u16 tx_vid = dsa_8021q_tx_vid(dp->ds, dp->index);
+	u16 queue_mapping = skb_get_queue_mapping(skb);
+	u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
+	struct sk_buff *clone = DSA_SKB_CB(skb)->clone;
+
+	/* TX timestamping was requested, so inject through MMIO */
+	if (clone)
+		return ocelot_xmit_ptp(dp, skb, clone);
+
+	return dsa_8021q_xmit(skb, netdev, ETH_P_8021Q,
+			      ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
+}
+
+static struct sk_buff *ocelot_rcv(struct sk_buff *skb,
+				  struct net_device *netdev,
+				  struct packet_type *pt)
+{
+	int src_port, switch_id, qos_class;
+	u16 vid, tci;
+
+	skb_push_rcsum(skb, ETH_HLEN);
+	if (skb_vlan_tag_present(skb)) {
+		tci = skb_vlan_tag_get(skb);
+		__vlan_hwaccel_clear_tag(skb);
+	} else {
+		__skb_vlan_pop(skb, &tci);
+	}
+	skb_pull_rcsum(skb, ETH_HLEN);
+
+	vid = tci & VLAN_VID_MASK;
+	src_port = dsa_8021q_rx_source_port(vid);
+	switch_id = dsa_8021q_rx_switch_id(vid);
+	qos_class = (tci & VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
+
+	skb->dev = dsa_master_find_slave(netdev, switch_id, src_port);
+	if (!skb->dev)
+		return NULL;
+
+	skb->offload_fwd_mark = 1;
+	skb->priority = qos_class;
+
+	return skb;
+}
+
+static const struct dsa_device_ops ocelot_8021q_netdev_ops = {
+	.name			= "ocelot-8021q",
+	.proto			= DSA_TAG_PROTO_OCELOT_8021Q,
+	.xmit			= ocelot_xmit,
+	.rcv			= ocelot_rcv,
+	.overhead		= VLAN_HLEN,
+	.promisc_on_master	= true,
+};
+
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT_8021Q);
+
+module_dsa_tag_driver(ocelot_8021q_netdev_ops);