net: lan966x: Add port mirroring support using tc-matchall

Add support for port mirroring. It is possible to mirror only one port
at a time and it is possible to have both ingress and egress mirroring.
Frames injected by the CPU don't get egress mirrored because they are
bypassing the analyzer module.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/microchip/lan966x/Makefile

@@ -11,4 +11,4 @@ lan966x-switch-objs  := lan966x_main.o lan966x_phylink.o lan966x_port.o \
 			lan966x_ptp.o lan966x_fdma.o lan966x_lag.o \
 			lan966x_tc.o lan966x_mqprio.o lan966x_taprio.o \
 			lan966x_tbf.o lan966x_cbs.o lan966x_ets.o \
-			lan966x_tc_matchall.o lan966x_police.o
+			lan966x_tc_matchall.o lan966x_police.o lan966x_mirror.o

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

@@ -264,6 +264,11 @@ struct lan966x {
 	struct lan966x_rx rx;
 	struct lan966x_tx tx;
 	struct napi_struct napi;
+
+	/* Mirror */
+	struct lan966x_port *mirror_monitor;
+	u32 mirror_mask[2];
+	u32 mirror_count;
 };
 
 struct lan966x_port_config {
@@ -279,7 +284,10 @@ struct lan966x_port_config {
 struct lan966x_port_tc {
 	bool ingress_shared_block;
 	unsigned long police_id;
+	unsigned long ingress_mirror_id;
+	unsigned long egress_mirror_id;
 	struct flow_stats police_stat;
+	struct flow_stats mirror_stat;
 };
 
 struct lan966x_port {
@@ -505,6 +513,18 @@ int lan966x_police_port_del(struct lan966x_port *port,
 void lan966x_police_port_stats(struct lan966x_port *port,
 			       struct flow_stats *stats);
 
+int lan966x_mirror_port_add(struct lan966x_port *port,
+			    struct flow_action_entry *action,
+			    unsigned long mirror_id,
+			    bool ingress,
+			    struct netlink_ext_ack *extack);
+int lan966x_mirror_port_del(struct lan966x_port *port,
+			    bool ingress,
+			    struct netlink_ext_ack *extack);
+void lan966x_mirror_port_stats(struct lan966x_port *port,
+			       struct flow_stats *stats,
+			       bool ingress);
+
 static inline void __iomem *lan_addr(void __iomem *base[],
 				     int id, int tinst, int tcnt,
 				     int gbase, int ginst,

drivers/net/ethernet/microchip/lan966x/lan966x_mirror.c

+// SPDX-License-Identifier: GPL-2.0+
+
+#include "lan966x_main.h"
+
+int lan966x_mirror_port_add(struct lan966x_port *port,
+			    struct flow_action_entry *action,
+			    unsigned long mirror_id,
+			    bool ingress,
+			    struct netlink_ext_ack *extack)
+{
+	struct lan966x *lan966x = port->lan966x;
+	struct lan966x_port *monitor_port;
+
+	if (!lan966x_netdevice_check(action->dev)) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Destination not an lan966x port");
+		return -EOPNOTSUPP;
+	}
+
+	monitor_port = netdev_priv(action->dev);
+
+	if (lan966x->mirror_mask[ingress] & BIT(port->chip_port)) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Mirror already exists");
+		return -EEXIST;
+	}
+
+	if (lan966x->mirror_monitor &&
+	    lan966x->mirror_monitor != monitor_port) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Cannot change mirror port while in use");
+		return -EBUSY;
+	}
+
+	if (port == monitor_port) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Cannot mirror the monitor port");
+		return -EINVAL;
+	}
+
+	lan966x->mirror_mask[ingress] |= BIT(port->chip_port);
+
+	lan966x->mirror_monitor = monitor_port;
+	lan_wr(BIT(monitor_port->chip_port), lan966x, ANA_MIRRORPORTS);
+
+	if (ingress) {
+		lan_rmw(ANA_PORT_CFG_SRC_MIRROR_ENA_SET(1),
+			ANA_PORT_CFG_SRC_MIRROR_ENA,
+			lan966x, ANA_PORT_CFG(port->chip_port));
+	} else {
+		lan_wr(lan966x->mirror_mask[0], lan966x,
+		       ANA_EMIRRORPORTS);
+	}
+
+	lan966x->mirror_count++;
+
+	if (ingress)
+		port->tc.ingress_mirror_id = mirror_id;
+	else
+		port->tc.egress_mirror_id = mirror_id;
+
+	return 0;
+}
+
+int lan966x_mirror_port_del(struct lan966x_port *port,
+			    bool ingress,
+			    struct netlink_ext_ack *extack)
+{
+	struct lan966x *lan966x = port->lan966x;
+
+	if (!(lan966x->mirror_mask[ingress] & BIT(port->chip_port))) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "There is no mirroring for this port");
+		return -ENOENT;
+	}
+
+	lan966x->mirror_mask[ingress] &= ~BIT(port->chip_port);
+
+	if (ingress) {
+		lan_rmw(ANA_PORT_CFG_SRC_MIRROR_ENA_SET(0),
+			ANA_PORT_CFG_SRC_MIRROR_ENA,
+			lan966x, ANA_PORT_CFG(port->chip_port));
+	} else {
+		lan_wr(lan966x->mirror_mask[0], lan966x,
+		       ANA_EMIRRORPORTS);
+	}
+
+	lan966x->mirror_count--;
+
+	if (lan966x->mirror_count == 0) {
+		lan966x->mirror_monitor = NULL;
+		lan_wr(0, lan966x, ANA_MIRRORPORTS);
+	}
+
+	if (ingress)
+		port->tc.ingress_mirror_id = 0;
+	else
+		port->tc.egress_mirror_id = 0;
+
+	return 0;
+}
+
+void lan966x_mirror_port_stats(struct lan966x_port *port,
+			       struct flow_stats *stats,
+			       bool ingress)
+{
+	struct rtnl_link_stats64 new_stats;
+	struct flow_stats *old_stats;
+
+	old_stats = &port->tc.mirror_stat;
+	lan966x_stats_get(port->dev, &new_stats);
+
+	if (ingress) {
+		flow_stats_update(stats,
+				  new_stats.rx_bytes - old_stats->bytes,
+				  new_stats.rx_packets - old_stats->pkts,
+				  new_stats.rx_dropped - old_stats->drops,
+				  old_stats->lastused,
+				  FLOW_ACTION_HW_STATS_IMMEDIATE);
+
+		old_stats->bytes = new_stats.rx_bytes;
+		old_stats->pkts = new_stats.rx_packets;
+		old_stats->drops = new_stats.rx_dropped;
+		old_stats->lastused = jiffies;
+	} else {
+		flow_stats_update(stats,
+				  new_stats.tx_bytes - old_stats->bytes,
+				  new_stats.tx_packets - old_stats->pkts,
+				  new_stats.tx_dropped - old_stats->drops,
+				  old_stats->lastused,
+				  FLOW_ACTION_HW_STATS_IMMEDIATE);
+
+		old_stats->bytes = new_stats.tx_bytes;
+		old_stats->pkts = new_stats.tx_packets;
+		old_stats->drops = new_stats.tx_dropped;
+		old_stats->lastused = jiffies;
+	}
+}

drivers/net/ethernet/microchip/lan966x/lan966x_regs.h

@@ -90,6 +90,24 @@ enum lan966x_target {
 #define ANA_AUTOAGE_AGE_PERIOD_GET(x)\
 	FIELD_GET(ANA_AUTOAGE_AGE_PERIOD, x)
 
+/*      ANA:ANA:MIRRORPORTS */
+#define ANA_MIRRORPORTS           __REG(TARGET_ANA, 0, 1, 29824, 0, 1, 244, 60, 0, 1, 4)
+
+#define ANA_MIRRORPORTS_MIRRORPORTS              GENMASK(8, 0)
+#define ANA_MIRRORPORTS_MIRRORPORTS_SET(x)\
+	FIELD_PREP(ANA_MIRRORPORTS_MIRRORPORTS, x)
+#define ANA_MIRRORPORTS_MIRRORPORTS_GET(x)\
+	FIELD_GET(ANA_MIRRORPORTS_MIRRORPORTS, x)
+
+/*      ANA:ANA:EMIRRORPORTS */
+#define ANA_EMIRRORPORTS          __REG(TARGET_ANA, 0, 1, 29824, 0, 1, 244, 64, 0, 1, 4)
+
+#define ANA_EMIRRORPORTS_EMIRRORPORTS            GENMASK(8, 0)
+#define ANA_EMIRRORPORTS_EMIRRORPORTS_SET(x)\
+	FIELD_PREP(ANA_EMIRRORPORTS_EMIRRORPORTS, x)
+#define ANA_EMIRRORPORTS_EMIRRORPORTS_GET(x)\
+	FIELD_GET(ANA_EMIRRORPORTS_EMIRRORPORTS, x)
+
 /*      ANA:ANA:FLOODING */
 #define ANA_FLOODING(r)           __REG(TARGET_ANA, 0, 1, 29824, 0, 1, 244, 68, r, 8, 4)
 
@@ -330,6 +348,12 @@ enum lan966x_target {
 /*      ANA:PORT:PORT_CFG */
 #define ANA_PORT_CFG(g)           __REG(TARGET_ANA, 0, 1, 28672, g, 9, 128, 112, 0, 1, 4)
 
+#define ANA_PORT_CFG_SRC_MIRROR_ENA              BIT(13)
+#define ANA_PORT_CFG_SRC_MIRROR_ENA_SET(x)\
+	FIELD_PREP(ANA_PORT_CFG_SRC_MIRROR_ENA, x)
+#define ANA_PORT_CFG_SRC_MIRROR_ENA_GET(x)\
+	FIELD_GET(ANA_PORT_CFG_SRC_MIRROR_ENA, x)
+
 #define ANA_PORT_CFG_LEARNAUTO                   BIT(6)
 #define ANA_PORT_CFG_LEARNAUTO_SET(x)\
 	FIELD_PREP(ANA_PORT_CFG_LEARNAUTO, x)

drivers/net/ethernet/microchip/lan966x/lan966x_tc_matchall.c

@@ -20,6 +20,9 @@ static int lan966x_tc_matchall_add(struct lan966x_port *port,
 		return lan966x_police_port_add(port, &f->rule->action, act,
 					       f->cookie, ingress,
 					       f->common.extack);
+	case FLOW_ACTION_MIRRED:
+		return lan966x_mirror_port_add(port, act, f->cookie,
+					       ingress, f->common.extack);
 	default:
 		NL_SET_ERR_MSG_MOD(f->common.extack,
 				   "Unsupported action");
@@ -36,6 +39,10 @@ static int lan966x_tc_matchall_del(struct lan966x_port *port,
 	if (f->cookie == port->tc.police_id) {
 		return lan966x_police_port_del(port, f->cookie,
 					       f->common.extack);
+	} else if (f->cookie == port->tc.ingress_mirror_id ||
+		   f->cookie == port->tc.egress_mirror_id) {
+		return lan966x_mirror_port_del(port, ingress,
+					       f->common.extack);
 	} else {
 		NL_SET_ERR_MSG_MOD(f->common.extack,
 				   "Unsupported action");
@@ -51,6 +58,9 @@ static int lan966x_tc_matchall_stats(struct lan966x_port *port,
 {
 	if (f->cookie == port->tc.police_id) {
 		lan966x_police_port_stats(port, &f->stats);
+	} else if (f->cookie == port->tc.ingress_mirror_id ||
+		   f->cookie == port->tc.egress_mirror_id) {
+		lan966x_mirror_port_stats(port, &f->stats, ingress);
 	} else {
 		NL_SET_ERR_MSG_MOD(f->common.extack,
 				   "Unsupported action");