net: lan966x: Update mdb when enabling/disabling mcast_snooping

When the multicast snooping is disabled, the mdb entries should be
removed from the HW, but they still need to be kept in memory for when
the mcast_snooping will be enabled again.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/microchip/lan966x/lan966x_main.h

@@ -267,6 +267,8 @@ int lan966x_handle_port_mdb_del(struct lan966x_port *port,
 				const struct switchdev_obj *obj);
 void lan966x_mdb_erase_entries(struct lan966x *lan966x, u16 vid);
 void lan966x_mdb_write_entries(struct lan966x *lan966x, u16 vid);
+void lan966x_mdb_clear_entries(struct lan966x *lan966x);
+void lan966x_mdb_restore_entries(struct lan966x *lan966x);
 
 int lan966x_ptp_init(struct lan966x *lan966x);
 void lan966x_ptp_deinit(struct lan966x *lan966x);

drivers/net/ethernet/microchip/lan966x/lan966x_mdb.c

@@ -504,3 +504,48 @@ void lan966x_mdb_erase_entries(struct lan966x *lan966x, u16 vid)
 			lan966x_mdb_l2_cpu_remove(lan966x, mdb_entry, type);
 	}
 }
+
+void lan966x_mdb_clear_entries(struct lan966x *lan966x)
+{
+	struct lan966x_mdb_entry *mdb_entry;
+	enum macaccess_entry_type type;
+	unsigned char mac[ETH_ALEN];
+
+	list_for_each_entry(mdb_entry, &lan966x->mdb_entries, list) {
+		type = lan966x_mdb_classify(mdb_entry->mac);
+
+		lan966x_mdb_encode_mac(mac, mdb_entry, type);
+		/* Remove just the MAC entry, still keep the PGID in case of L2
+		 * entries because this can be restored at later point
+		 */
+		lan966x_mac_forget(lan966x, mac, mdb_entry->vid, type);
+	}
+}
+
+void lan966x_mdb_restore_entries(struct lan966x *lan966x)
+{
+	struct lan966x_mdb_entry *mdb_entry;
+	enum macaccess_entry_type type;
+	unsigned char mac[ETH_ALEN];
+	bool cpu_copy = false;
+
+	list_for_each_entry(mdb_entry, &lan966x->mdb_entries, list) {
+		type = lan966x_mdb_classify(mdb_entry->mac);
+
+		lan966x_mdb_encode_mac(mac, mdb_entry, type);
+		if (type == ENTRYTYPE_MACV4 || type == ENTRYTYPE_MACV6) {
+			/* Copy the frame to CPU only if the CPU is in the VLAN */
+			if (lan966x_vlan_cpu_member_cpu_vlan_mask(lan966x,
+								  mdb_entry->vid) &&
+			    mdb_entry->cpu_copy)
+				cpu_copy = true;
+
+			lan966x_mac_ip_learn(lan966x, cpu_copy, mac,
+					     mdb_entry->vid, type);
+		} else {
+			lan966x_mac_learn(lan966x, mdb_entry->pgid->index,
+					  mdb_entry->mac,
+					  mdb_entry->vid, type);
+		}
+	}
+}

drivers/net/ethernet/microchip/lan966x/lan966x_switchdev.c

@@ -185,6 +185,10 @@ static void lan966x_port_mc_set(struct lan966x_port *port, bool mcast_ena)
 	struct lan966x *lan966x = port->lan966x;
 
 	port->mcast_ena = mcast_ena;
+	if (mcast_ena)
+		lan966x_mdb_restore_entries(lan966x);
+	else
+		lan966x_mdb_clear_entries(lan966x);
 
 	lan_rmw(ANA_CPU_FWD_CFG_IGMP_REDIR_ENA_SET(mcast_ena) |
 		ANA_CPU_FWD_CFG_MLD_REDIR_ENA_SET(mcast_ena) |