linux/net/dsa/dsa.c
Brandon Streiff 90af1059c5 net: dsa: forward timestamping callbacks to switch drivers
Forward the rx/tx timestamp machinery from the dsa infrastructure to the
switch driver.

On the rx side, defer delivery of skbs until we have an rx timestamp.
This mimicks the behavior of skb_defer_rx_timestamp.

On the tx side, identify PTP packets, clone them, and pass them to the
underlying switch driver before we transmit. This mimicks the behavior
of skb_tx_timestamp.

Adjusted txstamp API to keep the allocation and freeing of the clone
in the same central function by Richard Cochran

Signed-off-by: Brandon Streiff <brandon.streiff@ni.com>
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-14 14:33:37 -05:00

323 lines
7.1 KiB
C

/*
* net/dsa/dsa.c - Hardware switch handling
* Copyright (c) 2008-2009 Marvell Semiconductor
* Copyright (c) 2013 Florian Fainelli <florian@openwrt.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/device.h>
#include <linux/list.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/notifier.h>
#include <linux/of.h>
#include <linux/of_mdio.h>
#include <linux/of_platform.h>
#include <linux/of_net.h>
#include <linux/of_gpio.h>
#include <linux/netdevice.h>
#include <linux/sysfs.h>
#include <linux/phy_fixed.h>
#include <linux/ptp_classify.h>
#include <linux/gpio/consumer.h>
#include <linux/etherdevice.h>
#include "dsa_priv.h"
static struct sk_buff *dsa_slave_notag_xmit(struct sk_buff *skb,
struct net_device *dev)
{
/* Just return the original SKB */
return skb;
}
static const struct dsa_device_ops none_ops = {
.xmit = dsa_slave_notag_xmit,
.rcv = NULL,
};
const struct dsa_device_ops *dsa_device_ops[DSA_TAG_LAST] = {
#ifdef CONFIG_NET_DSA_TAG_BRCM
[DSA_TAG_PROTO_BRCM] = &brcm_netdev_ops,
#endif
#ifdef CONFIG_NET_DSA_TAG_BRCM_PREPEND
[DSA_TAG_PROTO_BRCM_PREPEND] = &brcm_prepend_netdev_ops,
#endif
#ifdef CONFIG_NET_DSA_TAG_DSA
[DSA_TAG_PROTO_DSA] = &dsa_netdev_ops,
#endif
#ifdef CONFIG_NET_DSA_TAG_EDSA
[DSA_TAG_PROTO_EDSA] = &edsa_netdev_ops,
#endif
#ifdef CONFIG_NET_DSA_TAG_KSZ
[DSA_TAG_PROTO_KSZ] = &ksz_netdev_ops,
#endif
#ifdef CONFIG_NET_DSA_TAG_LAN9303
[DSA_TAG_PROTO_LAN9303] = &lan9303_netdev_ops,
#endif
#ifdef CONFIG_NET_DSA_TAG_MTK
[DSA_TAG_PROTO_MTK] = &mtk_netdev_ops,
#endif
#ifdef CONFIG_NET_DSA_TAG_QCA
[DSA_TAG_PROTO_QCA] = &qca_netdev_ops,
#endif
#ifdef CONFIG_NET_DSA_TAG_TRAILER
[DSA_TAG_PROTO_TRAILER] = &trailer_netdev_ops,
#endif
[DSA_TAG_PROTO_NONE] = &none_ops,
};
const struct dsa_device_ops *dsa_resolve_tag_protocol(int tag_protocol)
{
const struct dsa_device_ops *ops;
if (tag_protocol >= DSA_TAG_LAST)
return ERR_PTR(-EINVAL);
ops = dsa_device_ops[tag_protocol];
if (!ops)
return ERR_PTR(-ENOPROTOOPT);
return ops;
}
static int dev_is_class(struct device *dev, void *class)
{
if (dev->class != NULL && !strcmp(dev->class->name, class))
return 1;
return 0;
}
static struct device *dev_find_class(struct device *parent, char *class)
{
if (dev_is_class(parent, class)) {
get_device(parent);
return parent;
}
return device_find_child(parent, class, dev_is_class);
}
struct net_device *dsa_dev_to_net_device(struct device *dev)
{
struct device *d;
d = dev_find_class(dev, "net");
if (d != NULL) {
struct net_device *nd;
nd = to_net_dev(d);
dev_hold(nd);
put_device(d);
return nd;
}
return NULL;
}
EXPORT_SYMBOL_GPL(dsa_dev_to_net_device);
/* Determine if we should defer delivery of skb until we have a rx timestamp.
*
* Called from dsa_switch_rcv. For now, this will only work if tagging is
* enabled on the switch. Normally the MAC driver would retrieve the hardware
* timestamp when it reads the packet out of the hardware. However in a DSA
* switch, the DSA driver owning the interface to which the packet is
* delivered is never notified unless we do so here.
*/
static bool dsa_skb_defer_rx_timestamp(struct dsa_slave_priv *p,
struct sk_buff *skb)
{
struct dsa_switch *ds = p->dp->ds;
unsigned int type;
if (skb_headroom(skb) < ETH_HLEN)
return false;
__skb_push(skb, ETH_HLEN);
type = ptp_classify_raw(skb);
__skb_pull(skb, ETH_HLEN);
if (type == PTP_CLASS_NONE)
return false;
if (likely(ds->ops->port_rxtstamp))
return ds->ops->port_rxtstamp(ds, p->dp->index, skb, type);
return false;
}
static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *pt, struct net_device *unused)
{
struct dsa_port *cpu_dp = dev->dsa_ptr;
struct sk_buff *nskb = NULL;
struct pcpu_sw_netstats *s;
struct dsa_slave_priv *p;
if (unlikely(!cpu_dp)) {
kfree_skb(skb);
return 0;
}
skb = skb_unshare(skb, GFP_ATOMIC);
if (!skb)
return 0;
nskb = cpu_dp->rcv(skb, dev, pt);
if (!nskb) {
kfree_skb(skb);
return 0;
}
skb = nskb;
p = netdev_priv(skb->dev);
skb_push(skb, ETH_HLEN);
skb->pkt_type = PACKET_HOST;
skb->protocol = eth_type_trans(skb, skb->dev);
s = this_cpu_ptr(p->stats64);
u64_stats_update_begin(&s->syncp);
s->rx_packets++;
s->rx_bytes += skb->len;
u64_stats_update_end(&s->syncp);
if (dsa_skb_defer_rx_timestamp(p, skb))
return 0;
netif_receive_skb(skb);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static bool dsa_is_port_initialized(struct dsa_switch *ds, int p)
{
return dsa_is_user_port(ds, p) && ds->ports[p].slave;
}
int dsa_switch_suspend(struct dsa_switch *ds)
{
int i, ret = 0;
/* Suspend slave network devices */
for (i = 0; i < ds->num_ports; i++) {
if (!dsa_is_port_initialized(ds, i))
continue;
ret = dsa_slave_suspend(ds->ports[i].slave);
if (ret)
return ret;
}
if (ds->ops->suspend)
ret = ds->ops->suspend(ds);
return ret;
}
EXPORT_SYMBOL_GPL(dsa_switch_suspend);
int dsa_switch_resume(struct dsa_switch *ds)
{
int i, ret = 0;
if (ds->ops->resume)
ret = ds->ops->resume(ds);
if (ret)
return ret;
/* Resume slave network devices */
for (i = 0; i < ds->num_ports; i++) {
if (!dsa_is_port_initialized(ds, i))
continue;
ret = dsa_slave_resume(ds->ports[i].slave);
if (ret)
return ret;
}
return 0;
}
EXPORT_SYMBOL_GPL(dsa_switch_resume);
#endif
static struct packet_type dsa_pack_type __read_mostly = {
.type = cpu_to_be16(ETH_P_XDSA),
.func = dsa_switch_rcv,
};
static struct workqueue_struct *dsa_owq;
bool dsa_schedule_work(struct work_struct *work)
{
return queue_work(dsa_owq, work);
}
static ATOMIC_NOTIFIER_HEAD(dsa_notif_chain);
int register_dsa_notifier(struct notifier_block *nb)
{
return atomic_notifier_chain_register(&dsa_notif_chain, nb);
}
EXPORT_SYMBOL_GPL(register_dsa_notifier);
int unregister_dsa_notifier(struct notifier_block *nb)
{
return atomic_notifier_chain_unregister(&dsa_notif_chain, nb);
}
EXPORT_SYMBOL_GPL(unregister_dsa_notifier);
int call_dsa_notifiers(unsigned long val, struct net_device *dev,
struct dsa_notifier_info *info)
{
info->dev = dev;
return atomic_notifier_call_chain(&dsa_notif_chain, val, info);
}
EXPORT_SYMBOL_GPL(call_dsa_notifiers);
static int __init dsa_init_module(void)
{
int rc;
dsa_owq = alloc_ordered_workqueue("dsa_ordered",
WQ_MEM_RECLAIM);
if (!dsa_owq)
return -ENOMEM;
rc = dsa_slave_register_notifier();
if (rc)
return rc;
rc = dsa_legacy_register();
if (rc)
return rc;
dev_add_pack(&dsa_pack_type);
return 0;
}
module_init(dsa_init_module);
static void __exit dsa_cleanup_module(void)
{
dsa_slave_unregister_notifier();
dev_remove_pack(&dsa_pack_type);
dsa_legacy_unregister();
destroy_workqueue(dsa_owq);
}
module_exit(dsa_cleanup_module);
MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:dsa");