net/mlx5e: Allow profile-specific limitation on max num of channels

Let SF/VF representor's netdev use profile-specific limitation on
max_nch to reduce its memory and HW resources consumption.

This is particularly important for environments with limited memory
and high number of SFs.
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Vu Pham <vuhuong@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

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

@@ -972,6 +972,7 @@ struct mlx5e_profile {
 	int	(*update_rx)(struct mlx5e_priv *priv);
 	void	(*update_stats)(struct mlx5e_priv *priv);
 	void	(*update_carrier)(struct mlx5e_priv *priv);
+	int	(*max_nch_limit)(struct mlx5_core_dev *mdev);
 	unsigned int (*stats_grps_num)(struct mlx5e_priv *priv);
 	mlx5e_stats_grp_t *stats_grps;
 	const struct mlx5e_rx_handlers *rx_handlers;

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

@@ -5098,6 +5098,18 @@ static const struct mlx5e_profile mlx5e_nic_profile = {
 		BIT(MLX5E_PROFILE_FEATURE_QOS_HTB),
 };
 
+static int mlx5e_profile_max_num_channels(struct mlx5_core_dev *mdev,
+					  const struct mlx5e_profile *profile)
+{
+	int nch;
+
+	nch = mlx5e_get_max_num_channels(mdev);
+
+	if (profile->max_nch_limit)
+		nch = min_t(int, nch, profile->max_nch_limit(mdev));
+	return nch;
+}
+
 static unsigned int
 mlx5e_calc_max_nch(struct mlx5_core_dev *mdev, struct net_device *netdev,
 		   const struct mlx5e_profile *profile)
@@ -5106,7 +5118,7 @@ mlx5e_calc_max_nch(struct mlx5_core_dev *mdev, struct net_device *netdev,
 	unsigned int max_nch, tmp;
 
 	/* core resources */
-	max_nch = mlx5e_get_max_num_channels(mdev);
+	max_nch = mlx5e_profile_max_num_channels(mdev, profile);
 
 	/* netdev rx queues */
 	tmp = netdev->num_rx_queues / max_t(u8, profile->rq_groups, 1);
@@ -5235,7 +5247,7 @@ static unsigned int mlx5e_get_max_num_txqs(struct mlx5_core_dev *mdev,
 {
 	unsigned int nch, ptp_txqs, qos_txqs;
 
-	nch = mlx5e_get_max_num_channels(mdev);
+	nch = mlx5e_profile_max_num_channels(mdev, profile);
 
 	ptp_txqs = MLX5_CAP_GEN(mdev, ts_cqe_to_dest_cqn) &&
 		mlx5e_profile_feature_cap(profile, PTP_TX) ?
@@ -5253,7 +5265,7 @@ static unsigned int mlx5e_get_max_num_rxqs(struct mlx5_core_dev *mdev,
 {
 	unsigned int nch;
 
-	nch = mlx5e_get_max_num_channels(mdev);
+	nch = mlx5e_profile_max_num_channels(mdev, profile);
 
 	return nch * profile->rq_groups;
 }

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

@@ -591,6 +591,12 @@ bool mlx5e_eswitch_vf_rep(const struct net_device *netdev)
 	return netdev->netdev_ops == &mlx5e_netdev_ops_rep;
 }
 
+static int mlx5e_rep_max_nch_limit(struct mlx5_core_dev *mdev)
+{
+	return (1 << MLX5_CAP_GEN(mdev, log_max_tir)) /
+		mlx5_eswitch_get_total_vports(mdev);
+}
+
 static void mlx5e_build_rep_params(struct net_device *netdev)
 {
 	struct mlx5e_priv *priv = netdev_priv(netdev);
@@ -1113,6 +1119,7 @@ static const struct mlx5e_profile mlx5e_rep_profile = {
 	.rq_groups		= MLX5E_NUM_RQ_GROUPS(REGULAR),
 	.stats_grps		= mlx5e_rep_stats_grps,
 	.stats_grps_num		= mlx5e_rep_stats_grps_num,
+	.max_nch_limit		= mlx5e_rep_max_nch_limit,
 };
 
 static const struct mlx5e_profile mlx5e_uplink_rep_profile = {