tag_xrs700x.c
// SPDX-License-Identifier: GPL-2.0+
/*
* XRS700x tag format handling
* Copyright (c) 2008-2009 Marvell Semiconductor
* Copyright (c) 2020 NovaTech LLC
*/
#include <linux/bitops.h>
#include "dsa_priv.h"
static struct sk_buff *xrs700x_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct dsa_port *partner, *dp = dsa_slave_to_port(dev);
u8 *trailer;
trailer = skb_put(skb, 1);
trailer[0] = BIT(dp->index);
if (dp->hsr_dev)
dsa_hsr_foreach_port(partner, dp->ds, dp->hsr_dev)
if (partner != dp)
trailer[0] |= BIT(partner->index);
return skb;
}
static struct sk_buff *xrs700x_rcv(struct sk_buff *skb, struct net_device *dev)
{
int source_port;
u8 *trailer;
trailer = skb_tail_pointer(skb) - 1;
source_port = ffs((int)trailer[0]) - 1;
if (source_port < 0)
return NULL;
skb->dev = dsa_master_find_slave(dev, 0, source_port);
if (!skb->dev)
return NULL;
if (pskb_trim_rcsum(skb, skb->len - 1))
return NULL;
/* Frame is forwarded by hardware, don't forward in software. */
dsa_default_offload_fwd_mark(skb);
return skb;
}
static const struct dsa_device_ops xrs700x_netdev_ops = {
.name = "xrs700x",
.proto = DSA_TAG_PROTO_XRS700X,
.xmit = xrs700x_xmit,
.rcv = xrs700x_rcv,
.needed_tailroom = 1,
};
MODULE_LICENSE("GPL");
MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_XRS700X);
module_dsa_tag_driver(xrs700x_netdev_ops);