net/mlx5e: Avoid query PPCNT register if not supported by the device

PPCNT is not supported if PCAM access reg is supported and ppcnt bit is clear.
Signed-off-by: Eyal Davidovich <eyald@mellanox.com>
Reviewed-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

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

@@ -483,6 +483,9 @@ static int mlx5e_grp_802_3_fill_stats(struct mlx5e_priv *priv, u64 *data,
 	return idx;
 }
 
+#define MLX5_BASIC_PPCNT_SUPPORTED(mdev) \
+	(MLX5_CAP_GEN(mdev, pcam_reg) ? MLX5_CAP_PCAM_REG(mdev, ppcnt) : 1)
+
 static void mlx5e_grp_802_3_update_stats(struct mlx5e_priv *priv)
 {
 	struct mlx5e_pport_stats *pstats = &priv->stats.pport;
@@ -491,6 +494,9 @@ static void mlx5e_grp_802_3_update_stats(struct mlx5e_priv *priv)
 	int sz = MLX5_ST_SZ_BYTES(ppcnt_reg);
 	void *out;
 
+	if (!MLX5_BASIC_PPCNT_SUPPORTED(mdev))
+		return;
+
 	MLX5_SET(ppcnt_reg, in, local_port, 1);
 	out = pstats->IEEE_802_3_counters;
 	MLX5_SET(ppcnt_reg, in, grp, MLX5_IEEE_802_3_COUNTERS_GROUP);
@@ -603,6 +609,9 @@ static void mlx5e_grp_2819_update_stats(struct mlx5e_priv *priv)
 	int sz = MLX5_ST_SZ_BYTES(ppcnt_reg);
 	void *out;
 
+	if (!MLX5_BASIC_PPCNT_SUPPORTED(mdev))
+		return;
+
 	MLX5_SET(ppcnt_reg, in, local_port, 1);
 	out = pstats->RFC_2819_counters;
 	MLX5_SET(ppcnt_reg, in, grp, MLX5_RFC_2819_COUNTERS_GROUP);
@@ -1078,6 +1087,9 @@ static void mlx5e_grp_per_prio_update_stats(struct mlx5e_priv *priv)
 	int prio;
 	void *out;
 
+	if (!MLX5_BASIC_PPCNT_SUPPORTED(mdev))
+		return;
+
 	MLX5_SET(ppcnt_reg, in, local_port, 1);
 	MLX5_SET(ppcnt_reg, in, grp, MLX5_PER_PRIORITY_COUNTERS_GROUP);
 	for (prio = 0; prio < NUM_PPORT_PRIO; prio++) {

include/linux/mlx5/mlx5_ifc.h

@@ -8283,7 +8283,9 @@ struct mlx5_ifc_pcam_regs_5000_to_507f_bits {
 	u8         port_access_reg_cap_mask_31_to_13[0x13];
 	u8         pbmc[0x1];
 	u8         pptb[0x1];
-	u8         port_access_reg_cap_mask_10_to_0[0xb];
+	u8         port_access_reg_cap_mask_10_to_09[0x2];
+	u8         ppcnt[0x1];
+	u8         port_access_reg_cap_mask_07_to_00[0x8];
 };
 
 struct mlx5_ifc_pcam_reg_bits {