net/mlx5e: ethtool: get_link_ext_stats for PHY down events

Implement ethtool_op get_link_ext_stats for PHY down events
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>

drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c

@@ -2463,4 +2463,5 @@ const struct ethtool_ops mlx5e_ethtool_ops = {
 	.get_eth_mac_stats = mlx5e_get_eth_mac_stats,
 	.get_eth_ctrl_stats = mlx5e_get_eth_ctrl_stats,
 	.get_rmon_stats    = mlx5e_get_rmon_stats,
+	.get_link_ext_stats = mlx5e_get_link_ext_stats
 };

drivers/net/ethernet/mellanox/mlx5/core/en_stats.c

@@ -1241,6 +1241,23 @@ static MLX5E_DECLARE_STATS_GRP_OP_UPDATE_STATS(phy)
 	mlx5_core_access_reg(mdev, in, sz, out, sz, MLX5_REG_PPCNT, 0, 0);
 }
 
+void mlx5e_get_link_ext_stats(struct net_device *dev,
+			      struct ethtool_link_ext_stats *stats)
+{
+	struct mlx5e_priv *priv = netdev_priv(dev);
+	u32 out[MLX5_ST_SZ_DW(ppcnt_reg)] = {};
+	u32 in[MLX5_ST_SZ_DW(ppcnt_reg)] = {};
+	int sz = MLX5_ST_SZ_BYTES(ppcnt_reg);
+
+	MLX5_SET(ppcnt_reg, in, local_port, 1);
+	MLX5_SET(ppcnt_reg, in, grp, MLX5_PHYSICAL_LAYER_COUNTERS_GROUP);
+	mlx5_core_access_reg(priv->mdev, in, sz, out,
+			     MLX5_ST_SZ_BYTES(ppcnt_reg), MLX5_REG_PPCNT, 0, 0);
+
+	stats->link_down_events = MLX5_GET(ppcnt_reg, out,
+					   counter_set.phys_layer_cntrs.link_down_events);
+}
+
 static int fec_num_lanes(struct mlx5_core_dev *dev)
 {
 	u32 out[MLX5_ST_SZ_DW(pmlp_reg)] = {};

drivers/net/ethernet/mellanox/mlx5/core/en_stats.h

@@ -126,6 +126,8 @@ void mlx5e_stats_eth_ctrl_get(struct mlx5e_priv *priv,
 void mlx5e_stats_rmon_get(struct mlx5e_priv *priv,
 			  struct ethtool_rmon_stats *rmon,
 			  const struct ethtool_rmon_hist_range **ranges);
+void mlx5e_get_link_ext_stats(struct net_device *dev,
+			      struct ethtool_link_ext_stats *stats);
 
 /* Concrete NIC Stats */