1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright 2020-2021 NXP Semiconductors 3 * 4 * An implementation of the software-defined tag_8021q.c tagger format, which 5 * also preserves full functionality under a vlan_filtering bridge. It does 6 * this by using the TCAM engines for: 7 * - pushing the RX VLAN as a second, outer tag, on egress towards the CPU port 8 * - redirecting towards the correct front port based on TX VLAN and popping 9 * that on egress 10 */ 11 #include <linux/dsa/8021q.h> 12 #include <soc/mscc/ocelot.h> 13 #include <soc/mscc/ocelot_ptp.h> 14 #include "dsa_priv.h" 15 16 static struct sk_buff *ocelot_xmit(struct sk_buff *skb, 17 struct net_device *netdev) 18 { 19 struct dsa_port *dp = dsa_slave_to_port(netdev); 20 u16 tx_vid = dsa_8021q_tx_vid(dp->ds, dp->index); 21 u16 queue_mapping = skb_get_queue_mapping(skb); 22 u8 pcp = netdev_txq_to_tc(netdev, queue_mapping); 23 struct ocelot *ocelot = dp->ds->priv; 24 int port = dp->index; 25 u32 rew_op = 0; 26 27 rew_op = ocelot_ptp_rew_op(skb); 28 if (rew_op) { 29 if (!ocelot_can_inject(ocelot, 0)) 30 return NULL; 31 32 ocelot_port_inject_frame(ocelot, port, 0, rew_op, skb); 33 return NULL; 34 } 35 36 return dsa_8021q_xmit(skb, netdev, ETH_P_8021Q, 37 ((pcp << VLAN_PRIO_SHIFT) | tx_vid)); 38 } 39 40 static struct sk_buff *ocelot_rcv(struct sk_buff *skb, 41 struct net_device *netdev, 42 struct packet_type *pt) 43 { 44 int src_port, switch_id, qos_class; 45 u16 vid, tci; 46 47 skb_push_rcsum(skb, ETH_HLEN); 48 if (skb_vlan_tag_present(skb)) { 49 tci = skb_vlan_tag_get(skb); 50 __vlan_hwaccel_clear_tag(skb); 51 } else { 52 __skb_vlan_pop(skb, &tci); 53 } 54 skb_pull_rcsum(skb, ETH_HLEN); 55 56 vid = tci & VLAN_VID_MASK; 57 src_port = dsa_8021q_rx_source_port(vid); 58 switch_id = dsa_8021q_rx_switch_id(vid); 59 qos_class = (tci & VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT; 60 61 skb->dev = dsa_master_find_slave(netdev, switch_id, src_port); 62 if (!skb->dev) 63 return NULL; 64 65 skb->offload_fwd_mark = 1; 66 skb->priority = qos_class; 67 68 return skb; 69 } 70 71 static const struct dsa_device_ops ocelot_8021q_netdev_ops = { 72 .name = "ocelot-8021q", 73 .proto = DSA_TAG_PROTO_OCELOT_8021Q, 74 .xmit = ocelot_xmit, 75 .rcv = ocelot_rcv, 76 .overhead = VLAN_HLEN, 77 .promisc_on_master = true, 78 }; 79 80 MODULE_LICENSE("GPL v2"); 81 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT_8021Q); 82 83 module_dsa_tag_driver(ocelot_8021q_netdev_ops); 84