1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright 2020-2021 NXP
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 <linux/dsa/ocelot.h>
13 #include "dsa_priv.h"
14
ocelot_defer_xmit(struct dsa_port * dp,struct sk_buff * skb)15 static struct sk_buff *ocelot_defer_xmit(struct dsa_port *dp,
16 struct sk_buff *skb)
17 {
18 struct felix_deferred_xmit_work *xmit_work;
19 struct felix_port *felix_port = dp->priv;
20
21 xmit_work = kzalloc(sizeof(*xmit_work), GFP_ATOMIC);
22 if (!xmit_work)
23 return NULL;
24
25 /* Calls felix_port_deferred_xmit in felix.c */
26 kthread_init_work(&xmit_work->work, felix_port->xmit_work_fn);
27 /* Increase refcount so the kfree_skb in dsa_slave_xmit
28 * won't really free the packet.
29 */
30 xmit_work->dp = dp;
31 xmit_work->skb = skb_get(skb);
32
33 kthread_queue_work(felix_port->xmit_worker, &xmit_work->work);
34
35 return NULL;
36 }
37
ocelot_xmit(struct sk_buff * skb,struct net_device * netdev)38 static struct sk_buff *ocelot_xmit(struct sk_buff *skb,
39 struct net_device *netdev)
40 {
41 struct dsa_port *dp = dsa_slave_to_port(netdev);
42 u16 queue_mapping = skb_get_queue_mapping(skb);
43 u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
44 u16 tx_vid = dsa_tag_8021q_tx_vid(dp);
45 struct ethhdr *hdr = eth_hdr(skb);
46
47 if (ocelot_ptp_rew_op(skb) || is_link_local_ether_addr(hdr->h_dest))
48 return ocelot_defer_xmit(dp, skb);
49
50 return dsa_8021q_xmit(skb, netdev, ETH_P_8021Q,
51 ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
52 }
53
ocelot_rcv(struct sk_buff * skb,struct net_device * netdev)54 static struct sk_buff *ocelot_rcv(struct sk_buff *skb,
55 struct net_device *netdev)
56 {
57 int src_port, switch_id;
58
59 dsa_8021q_rcv(skb, &src_port, &switch_id);
60
61 skb->dev = dsa_master_find_slave(netdev, switch_id, src_port);
62 if (!skb->dev)
63 return NULL;
64
65 dsa_default_offload_fwd_mark(skb);
66
67 return skb;
68 }
69
70 static const struct dsa_device_ops ocelot_8021q_netdev_ops = {
71 .name = "ocelot-8021q",
72 .proto = DSA_TAG_PROTO_OCELOT_8021Q,
73 .xmit = ocelot_xmit,
74 .rcv = ocelot_rcv,
75 .needed_headroom = VLAN_HLEN,
76 .promisc_on_master = true,
77 };
78
79 MODULE_LICENSE("GPL v2");
80 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT_8021Q);
81
82 module_dsa_tag_driver(ocelot_8021q_netdev_ops);
83