[PATCH net-next V2 7/7] net/mlx5: Add profile to auto-enable switchdev mode at device init

Tariq Toukan
2026-05-01T04:18:41Z

From: Mark Bloch <mbloch@nvidia.com>

Deployments that always operate in switchdev mode currently require
manual devlink configuration after driver probe, which complicates
automated provisioning.

Introduce MLX5_PROF_MASK_DEF_SWITCHDEV, a new profile mask bit, and
profile index 8. When a device is initialized or reloaded with this
profile, the driver automatically switches the e-switch to switchdev
mode by calling mlx5_devlink_eswitch_mode_set() immediately after
bringing the device online.

A no-op stub of mlx5_devlink_eswitch_mode_set() is added for builds
without CONFIG_MLX5_ESWITCH.

Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
---
.../net/ethernet/mellanox/mlx5/core/eswitch.h | 6 +++
.../net/ethernet/mellanox/mlx5/core/main.c | 43 ++++++++++++++++++-
include/linux/mlx5/driver.h | 2 +
3 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.h b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.h
index 3858690e09b4..cfb9595f9de8 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.h
@@ -1049,6 +1049,12 @@ mlx5_esw_lag_demux_rule_create(struct mlx5_eswitch *esw, u16 vport_num,
return ERR_PTR(-EOPNOTSUPP);
}

+static inline int
+mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
+ struct netlink_ext_ack *extack)
+{
+ return -EOPNOTSUPP;
+}
#endif /* CONFIG_MLX5_ESWITCH */

#endif /* __MLX5_ESWITCH_H__ */
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/main.c b/drivers/net/ethernet/mellanox/mlx5/core/main.c
index 74827e8ca125..4cdda15ed7f5 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/main.c
@@ -86,7 +86,7 @@ MODULE_PARM_DESC(debug_mask, "debug mask: 1 = dump cmd data, 2 = dump cmd exec t

static unsigned int prof_sel = MLX5_DEFAULT_PROF;
module_param_named(prof_sel, prof_sel, uint, 0444);
-MODULE_PARM_DESC(prof_sel, "profile selector. Valid range 0 - 2");
+MODULE_PARM_DESC(prof_sel, "profile selector. Valid range 0 - 3 and 8");

static u32 sw_owner_id[4];
#define MAX_SW_VHCA_ID (BIT(__mlx5_bit_sz(cmd_hca_cap_2, sw_vhca_id)) - 1)
@@ -99,6 +99,8 @@ enum {

#define LOG_MAX_SUPPORTED_QPS 0xff

+#define MLX5_PROF_SEL_LAST_NIC 3
+#define MLX5_PROF_SEL_FIRST_ESW 8
static struct mlx5_profile profile[] = {
[0] = {
.mask = 0,
@@ -120,6 +122,11 @@ static struct mlx5_profile profile[] = {
.log_max_qp = LOG_MAX_SUPPORTED_QPS,
.num_cmd_caches = 0,
},
+ [8] = {
+ .mask = MLX5_PROF_MASK_DEF_SWITCHDEV | MLX5_PROF_MASK_QP_SIZE,
+ .log_max_qp = LOG_MAX_SUPPORTED_QPS,
+ .num_cmd_caches = MLX5_NUM_COMMAND_CACHES,
+ },
};

static int wait_fw_init(struct mlx5_core_dev *dev, u32 max_wait_mili,
@@ -1385,6 +1392,22 @@ static void mlx5_unload(struct mlx5_core_dev *dev)
mlx5_free_bfreg(dev, &dev->priv.bfreg);
}

+static void mlx5_set_default_switchdev(struct mlx5_core_dev *dev)
+{
+ int err;
+
+ /* Default switchdev is best-effort; keep the device usable on
+ * failure.
+ */
+ err = mlx5_devlink_eswitch_mode_set(priv_to_devlink(dev),
+ DEVLINK_ESWITCH_MODE_SWITCHDEV,
+ NULL);
+ if (err && err != -EOPNOTSUPP)
+ mlx5_core_warn(dev,
+ "Failed to set switchdev as default, continuing in current mode, err(%d)\n",
+ err);
+}
+
int mlx5_init_one_devl_locked(struct mlx5_core_dev *dev)
{
bool light_probe = mlx5_dev_is_lightweight(dev);
@@ -1431,6 +1454,10 @@ int mlx5_init_one_devl_locked(struct mlx5_core_dev *dev)
mlx5_core_err(dev, "mlx5_hwmon_dev_register failed with error code %d\n", err);

mutex_unlock(&dev->intf_state_mutex);
+
+ if (dev->profile.mask & MLX5_PROF_MASK_DEF_SWITCHDEV)
+ mlx5_set_default_switchdev(dev);
+
return 0;

err_register:
@@ -1532,6 +1559,10 @@ int mlx5_load_one_devl_locked(struct mlx5_core_dev *dev, bool recovery)
goto err_attach;

mutex_unlock(&dev->intf_state_mutex);
+
+ if (dev->profile.mask & MLX5_PROF_MASK_DEF_SWITCHDEV)
+ mlx5_set_default_switchdev(dev);
+
return 0;

err_attach:
@@ -2314,6 +2345,16 @@ static void mlx5_core_verify_params(void)
MLX5_DEFAULT_PROF);
prof_sel = MLX5_DEFAULT_PROF;
}
+
+ if (prof_sel > MLX5_PROF_SEL_LAST_NIC &&
+ prof_sel < MLX5_PROF_SEL_FIRST_ESW) {
+ pr_warn("mlx5_core: WARNING: Invalid module parameter prof_sel %d invalid range %d - %d, changing back to default (%d)\n",
+ prof_sel,
+ MLX5_PROF_SEL_LAST_NIC + 1,
+ MLX5_PROF_SEL_FIRST_ESW - 1,
+ MLX5_DEFAULT_PROF);
+ prof_sel = MLX5_DEFAULT_PROF;
+ }
}

static int __init mlx5_init(void)
diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h
index 04b96c5abb57..65298c07df4d 100644
--- a/include/linux/mlx5/driver.h
+++ b/include/linux/mlx5/driver.h
@@ -705,6 +705,8 @@ struct mlx5_st;

enum {
MLX5_PROF_MASK_QP_SIZE = (u64)1 << 0,
+ MLX5_PROF_MASK_MR_CACHE = (u64)1 << 1,
+ MLX5_PROF_MASK_DEF_SWITCHDEV = (u64)1 << 2,
};

struct mlx5_profile {
--
2.44.0