net: dsa: microchip: add pause stats support

Add support for pause specific stats.

Tested on ksz9477.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/dsa/microchip/ksz_common.c

@@ -671,12 +671,14 @@ static void ksz_phylink_get_caps(struct dsa_switch *ds, int port,
 
 void ksz_r_mib_stats64(struct ksz_device *dev, int port)
 {
+	struct ethtool_pause_stats *pstats;
 	struct rtnl_link_stats64 *stats;
 	struct ksz_stats_raw *raw;
 	struct ksz_port_mib *mib;
 
 	mib = &dev->ports[port].mib;
 	stats = &mib->stats64;
+	pstats = &mib->pause_stats;
 	raw = (struct ksz_stats_raw *)mib->counters;
 
 	spin_lock(&mib->stats64_lock);
@@ -708,6 +710,9 @@ void ksz_r_mib_stats64(struct ksz_device *dev, int port)
 	stats->multicast = raw->rx_mcast;
 	stats->collisions = raw->tx_total_col;
 
+	pstats->tx_pause_frames = raw->tx_pause;
+	pstats->rx_pause_frames = raw->rx_pause;
+
 	spin_unlock(&mib->stats64_lock);
 }
 
@@ -724,6 +729,19 @@ static void ksz_get_stats64(struct dsa_switch *ds, int port,
 	spin_unlock(&mib->stats64_lock);
 }
 
+static void ksz_get_pause_stats(struct dsa_switch *ds, int port,
+				struct ethtool_pause_stats *pause_stats)
+{
+	struct ksz_device *dev = ds->priv;
+	struct ksz_port_mib *mib;
+
+	mib = &dev->ports[port].mib;
+
+	spin_lock(&mib->stats64_lock);
+	memcpy(pause_stats, &mib->pause_stats, sizeof(*pause_stats));
+	spin_unlock(&mib->stats64_lock);
+}
+
 static void ksz_get_strings(struct dsa_switch *ds, int port,
 			    u32 stringset, uint8_t *buf)
 {
@@ -1336,6 +1354,7 @@ static const struct dsa_switch_ops ksz_switch_ops = {
 	.port_mirror_add	= ksz_port_mirror_add,
 	.port_mirror_del	= ksz_port_mirror_del,
 	.get_stats64		= ksz_get_stats64,
+	.get_pause_stats	= ksz_get_pause_stats,
 	.port_change_mtu	= ksz_change_mtu,
 	.port_max_mtu		= ksz_max_mtu,
 };

drivers/net/dsa/microchip/ksz_common.h

@@ -25,6 +25,7 @@ struct ksz_port_mib {
 	u8 cnt_ptr;
 	u64 *counters;
 	struct rtnl_link_stats64 stats64;
+	struct ethtool_pause_stats pause_stats;
 	struct spinlock stats64_lock;
 };