mlxsw: spectrum: Fix SPAN egress mirroring buffer size for Spectrum-2

For SPAN egress mirroring buffer size, it is needed to use a different
formula for Spectrum and Spectrum-2. Move the buffer size computation to
ops and implement new formula for Spectrum-2.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum.c

@@ -195,6 +195,10 @@ struct mlxsw_sp_ptp_ops {
 			  u64 *data, int data_index);
 };
 
+struct mlxsw_sp_span_ops {
+	u32 (*buffsize_get)(int mtu, u32 speed);
+};
+
 static int mlxsw_sp_component_query(struct mlxfw_dev *mlxfw_dev,
 				    u16 component_index, u32 *p_max_size,
 				    u8 *p_align_bits, u16 *p_max_write_size)
@@ -4914,6 +4918,33 @@ static const struct mlxsw_sp_ptp_ops mlxsw_sp2_ptp_ops = {
 	.get_stats	= mlxsw_sp2_get_stats,
 };
 
+static u32 mlxsw_sp1_span_buffsize_get(int mtu, u32 speed)
+{
+	return mtu * 5 / 2;
+}
+
+static const struct mlxsw_sp_span_ops mlxsw_sp1_span_ops = {
+	.buffsize_get = mlxsw_sp1_span_buffsize_get,
+};
+
+#define MLXSW_SP2_SPAN_EG_MIRROR_BUFFER_FACTOR 38
+
+static u32 mlxsw_sp2_span_buffsize_get(int mtu, u32 speed)
+{
+	return 3 * mtu + MLXSW_SP2_SPAN_EG_MIRROR_BUFFER_FACTOR * speed / 1000;
+}
+
+static const struct mlxsw_sp_span_ops mlxsw_sp2_span_ops = {
+	.buffsize_get = mlxsw_sp2_span_buffsize_get,
+};
+
+u32 mlxsw_sp_span_buffsize_get(struct mlxsw_sp *mlxsw_sp, int mtu, u32 speed)
+{
+	u32 buffsize = mlxsw_sp->span_ops->buffsize_get(speed, mtu);
+
+	return mlxsw_sp_bytes_cells(mlxsw_sp, buffsize) + 1;
+}
+
 static int mlxsw_sp_netdevice_event(struct notifier_block *unused,
 				    unsigned long event, void *ptr);
 
@@ -5135,6 +5166,7 @@ static int mlxsw_sp1_init(struct mlxsw_core *mlxsw_core,
 	mlxsw_sp->sb_vals = &mlxsw_sp1_sb_vals;
 	mlxsw_sp->port_type_speed_ops = &mlxsw_sp1_port_type_speed_ops;
 	mlxsw_sp->ptp_ops = &mlxsw_sp1_ptp_ops;
+	mlxsw_sp->span_ops = &mlxsw_sp1_span_ops;
 	mlxsw_sp->listeners = mlxsw_sp1_listener;
 	mlxsw_sp->listeners_count = ARRAY_SIZE(mlxsw_sp1_listener);
 
@@ -5160,6 +5192,7 @@ static int mlxsw_sp2_init(struct mlxsw_core *mlxsw_core,
 	mlxsw_sp->sb_vals = &mlxsw_sp2_sb_vals;
 	mlxsw_sp->port_type_speed_ops = &mlxsw_sp2_port_type_speed_ops;
 	mlxsw_sp->ptp_ops = &mlxsw_sp2_ptp_ops;
+	mlxsw_sp->span_ops = &mlxsw_sp2_span_ops;
 
 	return mlxsw_sp_init(mlxsw_core, mlxsw_bus_info, extack);
 }
@@ -5181,6 +5214,7 @@ static int mlxsw_sp3_init(struct mlxsw_core *mlxsw_core,
 	mlxsw_sp->sb_vals = &mlxsw_sp2_sb_vals;
 	mlxsw_sp->port_type_speed_ops = &mlxsw_sp2_port_type_speed_ops;
 	mlxsw_sp->ptp_ops = &mlxsw_sp2_ptp_ops;
+	mlxsw_sp->span_ops = &mlxsw_sp2_span_ops;
 
 	return mlxsw_sp_init(mlxsw_core, mlxsw_bus_info, extack);
 }

drivers/net/ethernet/mellanox/mlxsw/spectrum.h

@@ -140,6 +140,7 @@ struct mlxsw_sp_sb_vals;
 struct mlxsw_sp_port_type_speed_ops;
 struct mlxsw_sp_ptp_state;
 struct mlxsw_sp_ptp_ops;
+struct mlxsw_sp_span_ops;
 
 struct mlxsw_sp_port_mapping {
 	u8 module;
@@ -185,6 +186,7 @@ struct mlxsw_sp {
 	const struct mlxsw_sp_sb_vals *sb_vals;
 	const struct mlxsw_sp_port_type_speed_ops *port_type_speed_ops;
 	const struct mlxsw_sp_ptp_ops *ptp_ops;
+	const struct mlxsw_sp_span_ops *span_ops;
 	const struct mlxsw_listener *listeners;
 	size_t listeners_count;
 };
@@ -502,6 +504,7 @@ int mlxsw_sp_flow_counter_alloc(struct mlxsw_sp *mlxsw_sp,
 				unsigned int *p_counter_index);
 void mlxsw_sp_flow_counter_free(struct mlxsw_sp *mlxsw_sp,
 				unsigned int counter_index);
+u32 mlxsw_sp_span_buffsize_get(struct mlxsw_sp *mlxsw_sp, int mtu, u32 speed);
 bool mlxsw_sp_port_dev_check(const struct net_device *dev);
 struct mlxsw_sp *mlxsw_sp_lower_get(struct net_device *dev);
 struct mlxsw_sp_port *mlxsw_sp_port_dev_lower_find(struct net_device *dev);

drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c

@@ -748,20 +748,22 @@ static bool mlxsw_sp_span_is_egress_mirror(struct mlxsw_sp_port *port)
 	return false;
 }
 
-static int mlxsw_sp_span_mtu_to_buffsize(const struct mlxsw_sp *mlxsw_sp,
-					 int mtu)
-{
-	return mlxsw_sp_bytes_cells(mlxsw_sp, mtu * 5 / 2) + 1;
-}
-
 static int
 mlxsw_sp_span_port_buffsize_update(struct mlxsw_sp_port *mlxsw_sp_port, u16 mtu)
 {
 	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
 	char sbib_pl[MLXSW_REG_SBIB_LEN];
 	u32 buffsize;
+	u32 speed;
+	int err;
 
-	buffsize = mlxsw_sp_span_mtu_to_buffsize(mlxsw_sp, mtu);
+	err = mlxsw_sp_port_speed_get(mlxsw_sp_port, &speed);
+	if (err)
+		return err;
+	if (speed == SPEED_UNKNOWN)
+		speed = 0;
+
+	buffsize = mlxsw_sp_span_buffsize_get(mlxsw_sp, speed, mtu);
 	mlxsw_reg_sbib_pack(sbib_pl, mlxsw_sp_port->local_port, buffsize);
 	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(sbib), sbib_pl);
 }