net: dsa: add support for offloading HSR

Add support for offloading of HSR/PRP (IEC 62439-3) tag insertion
tag removal, duplicate generation and forwarding on DSA switches.

Add DSA_NOTIFIER_HSR_JOIN and DSA_NOTIFIER_HSR_LEAVE which trigger calls
to .port_hsr_join and .port_hsr_leave in the DSA driver for the switch.

The DSA switch driver should then set netdev feature flags for the
HSR/PRP operation that it offloads.
    NETIF_F_HW_HSR_TAG_INS
    NETIF_F_HW_HSR_TAG_RM
    NETIF_F_HW_HSR_FWD
    NETIF_F_HW_HSR_DUP

Signed-off-by: George McCollister <george.mccollister@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index 8a1bcb2..7060f12 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -20,6 +20,8 @@ enum {
 	DSA_NOTIFIER_BRIDGE_LEAVE,
 	DSA_NOTIFIER_FDB_ADD,
 	DSA_NOTIFIER_FDB_DEL,
+	DSA_NOTIFIER_HSR_JOIN,
+	DSA_NOTIFIER_HSR_LEAVE,
 	DSA_NOTIFIER_LAG_CHANGE,
 	DSA_NOTIFIER_LAG_JOIN,
 	DSA_NOTIFIER_LAG_LEAVE,
@@ -100,6 +102,13 @@ struct dsa_switchdev_event_work {
 	u16 vid;
 };
 
+/* DSA_NOTIFIER_HSR_* */
+struct dsa_notifier_hsr_info {
+	struct net_device *hsr;
+	int sw_index;
+	int port;
+};
+
 struct dsa_slave_priv {
 	/* Copy of CPU port xmit for faster access in slave transmit hot path */
 	struct sk_buff *	(*xmit)(struct sk_buff *skb,
@@ -183,6 +192,8 @@ int dsa_port_vlan_del(struct dsa_port *dp,
 		      const struct switchdev_obj_port_vlan *vlan);
 int dsa_port_link_register_of(struct dsa_port *dp);
 void dsa_port_link_unregister_of(struct dsa_port *dp);
+int dsa_port_hsr_join(struct dsa_port *dp, struct net_device *hsr);
+void dsa_port_hsr_leave(struct dsa_port *dp, struct net_device *hsr);
 extern const struct phylink_mac_ops dsa_port_phylink_mac_ops;
 
 static inline bool dsa_port_offloads_netdev(struct dsa_port *dp,