mlxsw: Query maximum number of ports from firmware

We currently hard code the maximum number of ports in the driver, but
this may change in future devices, so query it from the firmware
instead.

Fallback to a maximum of 64 ports in case this number can't be queried.
This should only happen in SwitchX-2 for which this number is correct.

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

1 files changed, 42 insertions, 4 deletions

diff --git a/drivers/net/ethernet/mellanox/mlxsw/core.c b/drivers/net/ethernet/mellanox/mlxsw/core.c
index fb8187d6ca13..affe84eb4bff 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/core.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/core.c
@@ -110,11 +110,42 @@ struct mlxsw_core {
 	struct mlxsw_res res;
 	struct mlxsw_hwmon *hwmon;
 	struct mlxsw_thermal *thermal;
-	struct mlxsw_core_port ports[MLXSW_PORT_MAX_PORTS];
+	struct mlxsw_core_port *ports;
+	unsigned int max_ports;
 	unsigned long driver_priv[0];
 	/* driver_priv has to be always the last item */
 };
 
+#define MLXSW_PORT_MAX_PORTS_DEFAULT	0x40
+
+static int mlxsw_ports_init(struct mlxsw_core *mlxsw_core)
+{
+	/* Switch ports are numbered from 1 to queried value */
+	if (MLXSW_CORE_RES_VALID(mlxsw_core, MAX_SYSTEM_PORT))
+		mlxsw_core->max_ports = MLXSW_CORE_RES_GET(mlxsw_core,
+							   MAX_SYSTEM_PORT) + 1;
+	else
+		mlxsw_core->max_ports = MLXSW_PORT_MAX_PORTS_DEFAULT + 1;
+
+	mlxsw_core->ports = kcalloc(mlxsw_core->max_ports,
+				    sizeof(struct mlxsw_core_port), GFP_KERNEL);
+	if (!mlxsw_core->ports)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static void mlxsw_ports_fini(struct mlxsw_core *mlxsw_core)
+{
+	kfree(mlxsw_core->ports);
+}
+
+unsigned int mlxsw_core_max_ports(const struct mlxsw_core *mlxsw_core)
+{
+	return mlxsw_core->max_ports;
+}
+EXPORT_SYMBOL(mlxsw_core_max_ports);
+
 void *mlxsw_core_driver_priv(struct mlxsw_core *mlxsw_core)
 {
 	return mlxsw_core->driver_priv;
@@ -733,7 +764,7 @@ static int mlxsw_devlink_port_split(struct devlink *devlink,
 {
 	struct mlxsw_core *mlxsw_core = devlink_priv(devlink);
 
-	if (port_index >= MLXSW_PORT_MAX_PORTS)
+	if (port_index >= mlxsw_core->max_ports)
 		return -EINVAL;
 	if (!mlxsw_core->driver->port_split)
 		return -EOPNOTSUPP;
@@ -745,7 +776,7 @@ static int mlxsw_devlink_port_unsplit(struct devlink *devlink,
 {
 	struct mlxsw_core *mlxsw_core = devlink_priv(devlink);
 
-	if (port_index >= MLXSW_PORT_MAX_PORTS)
+	if (port_index >= mlxsw_core->max_ports)
 		return -EINVAL;
 	if (!mlxsw_core->driver->port_unsplit)
 		return -EOPNOTSUPP;
@@ -972,6 +1003,10 @@ int mlxsw_core_bus_device_register(const struct mlxsw_bus_info *mlxsw_bus_info,
 	if (err)
 		goto err_bus_init;
 
+	err = mlxsw_ports_init(mlxsw_core);
+	if (err)
+		goto err_ports_init;
+
 	if (MLXSW_CORE_RES_VALID(mlxsw_core, MAX_LAG) &&
 	    MLXSW_CORE_RES_VALID(mlxsw_core, MAX_LAG_MEMBERS)) {
 		alloc_size = sizeof(u8) *
@@ -1019,6 +1054,8 @@ err_devlink_register:
 err_emad_init:
 	kfree(mlxsw_core->lag.mapping);
 err_alloc_lag_mapping:
+	mlxsw_ports_fini(mlxsw_core);
+err_ports_init:
 	mlxsw_bus->fini(bus_priv);
 err_bus_init:
 	devlink_free(devlink);
@@ -1039,6 +1076,7 @@ void mlxsw_core_bus_device_unregister(struct mlxsw_core *mlxsw_core)
 	devlink_unregister(devlink);
 	mlxsw_emad_fini(mlxsw_core);
 	kfree(mlxsw_core->lag.mapping);
+	mlxsw_ports_fini(mlxsw_core);
 	mlxsw_core->bus->fini(mlxsw_core->bus_priv);
 	devlink_free(devlink);
 	mlxsw_core_driver_put(device_kind);
@@ -1508,7 +1546,7 @@ void mlxsw_core_skb_receive(struct mlxsw_core *mlxsw_core, struct sk_buff *skb,
 			    __func__, local_port, rx_info->trap_id);
 
 	if ((rx_info->trap_id >= MLXSW_TRAP_ID_MAX) ||
-	    (local_port >= MLXSW_PORT_MAX_PORTS))
+	    (local_port >= mlxsw_core->max_ports))
 		goto drop;
 
 	rcu_read_lock();