// SPDX-License-Identifier: GPL-2.0
/* Copyright 2020-2021 NXP
*
* 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 <linux/dsa/ocelot.h>
#include "tag.h"
#include "tag_8021q.h"
#define OCELOT_8021Q_NAME "ocelot-8021q"
struct ocelot_8021q_tagger_private {
struct ocelot_8021q_tagger_data data; /* Must be first */
struct kthread_worker *xmit_worker;
};
static struct sk_buff *ocelot_defer_xmit(struct dsa_port *dp,
struct sk_buff *skb)
{
struct ocelot_8021q_tagger_private *priv = dp->ds->tagger_data;
struct ocelot_8021q_tagger_data *data = &priv->data;
void (*xmit_work_fn)(struct kthread_work *work);
struct felix_deferred_xmit_work *xmit_work;
struct kthread_worker *xmit_worker;
xmit_work_fn = data->xmit_work_fn;
xmit_worker = priv->xmit_worker;
if (!xmit_work_fn || !xmit_worker)
return NULL;
/* PTP over IP packets need UDP checksumming. We may have inherited
* NETIF_F_HW_CSUM from the DSA conduit, but these packets are not sent
* through the DSA conduit, so calculate the checksum here.
*/
if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
return NULL;
xmit_work = kzalloc(sizeof(*xmit_work), GFP_ATOMIC);
if (!xmit_work)
return NULL;
/* Calls felix_port_deferred_xmit in felix.c */
kthread_init_work(&xmit_work->work, xmit_work_fn);
/* Increase refcount so the kfree_skb in dsa_user_xmit
* won't really free the packet.
*/
xmit_work->dp = dp;
xmit_work->skb = skb_get(skb);
kthread_queue_work(xmit_worker, &xmit_work->work);
return NULL;
}
static struct sk_buff *ocelot_xmit(struct sk_buff *skb,
struct net_device *netdev)
{
struct dsa_port *dp = dsa_user_to_port(netdev);
u16 queue_mapping = skb_get_queue_mapping(skb);
u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
u16 tx_vid = dsa_tag_8021q_standalone_vid(dp);
struct ethhdr *hdr = eth_hdr(skb);
if (ocelot_ptp_rew_op(skb) || is_link_local_ether_addr(hdr->h_dest))
return ocelot_defer_xmit(dp, skb);
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)
{
int src_port, switch_id;
dsa_8021q_rcv(skb, &src_port, &switch_id, NULL, NULL);
skb->dev = dsa_conduit_find_user(netdev, switch_id, src_port);
if (!skb->dev)
return NULL;
dsa_default_offload_fwd_mark(skb);
return skb;
}
static void ocelot_disconnect(struct dsa_switch *ds)
{
struct ocelot_8021q_tagger_private *priv = ds->tagger_data;
kthread_destroy_worker(priv->xmit_worker);
kfree(priv);
ds->tagger_data = NULL;
}
static int ocelot_connect(struct dsa_switch *ds)
{
struct ocelot_8021q_tagger_private *priv;
int err;
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->xmit_worker = kthread_create_worker(0, "felix_xmit");
if (IS_ERR(priv->xmit_worker)) {
err = PTR_ERR(priv->xmit_worker);
kfree(priv);
return err;
}
ds->tagger_data = priv;
return 0;
}
static const struct dsa_device_ops ocelot_8021q_netdev_ops = {
.name = OCELOT_8021Q_NAME,
.proto = DSA_TAG_PROTO_OCELOT_8021Q,
.xmit = ocelot_xmit,
.rcv = ocelot_rcv,
.connect = ocelot_connect,
.disconnect = ocelot_disconnect,
.needed_headroom = VLAN_HLEN,
.promisc_on_conduit = true,
};
MODULE_DESCRIPTION("DSA tag driver for Ocelot family of switches, using VLAN");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT_8021Q, OCELOT_8021Q_NAME);
module_dsa_tag_driver(ocelot_8021q_netdev_ops);