diff --git a/Documentation/networking/device_drivers/ethernet/mellanox/mlx5.rst b/Documentation/networking/device_drivers/ethernet/mellanox/mlx5.rst
index e9b65035cd47..a5eb22793bb9 100644
--- a/Documentation/networking/device_drivers/ethernet/mellanox/mlx5.rst
+++ b/Documentation/networking/device_drivers/ethernet/mellanox/mlx5.rst
@@ -97,6 +97,11 @@ Enabling the driver and kconfig options
 
 |   Provides low-level InfiniBand/RDMA and `RoCE <https://community.mellanox.com/s/article/recommended-network-configuration-examples-for-roce-deployment>`_ support.
 
+**CONFIG_MLX5_SF=(y/n)**
+
+|   Build support for subfunction.
+|   Subfunctons are more light weight than PCI SRIOV VFs. Choosing this option
+|   will enable support for creating subfunction devices.
 
 **External options** ( Choose if the corresponding mlx5 feature is required )
 
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/Makefile b/drivers/net/ethernet/mellanox/mlx5/core/Makefile
index 3abb286dbbea..2f9dede697dc 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/Makefile
+++ b/drivers/net/ethernet/mellanox/mlx5/core/Makefile
@@ -88,4 +88,4 @@ mlx5_core-$(CONFIG_MLX5_SW_STEERING) += steering/dr_domain.o steering/dr_table.o
 #
 # SF device
 #
-mlx5_core-$(CONFIG_MLX5_SF) += sf/vhca_event.o
+mlx5_core-$(CONFIG_MLX5_SF) += sf/vhca_event.o sf/dev/dev.o
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/main.c b/drivers/net/ethernet/mellanox/mlx5/core/main.c
index 6e67ad11c713..292c30e71d7f 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/main.c
@@ -74,6 +74,7 @@
 #include "lib/hv_vhca.h"
 #include "diag/rsc_dump.h"
 #include "sf/vhca_event.h"
+#include "sf/dev/dev.h"
 
 MODULE_AUTHOR("Eli Cohen <eli@mellanox.com>");
 MODULE_DESCRIPTION("Mellanox 5th generation network adapters (ConnectX series) core driver");
@@ -1155,6 +1156,8 @@ static int mlx5_load(struct mlx5_core_dev *dev)
 		goto err_sriov;
 	}
 
+	mlx5_sf_dev_table_create(dev);
+
 	return 0;
 
 err_sriov:
@@ -1186,6 +1189,7 @@ static int mlx5_load(struct mlx5_core_dev *dev)
 
 static void mlx5_unload(struct mlx5_core_dev *dev)
 {
+	mlx5_sf_dev_table_destroy(dev);
 	mlx5_sriov_detach(dev);
 	mlx5_ec_cleanup(dev);
 	mlx5_vhca_event_stop(dev);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c
new file mode 100644
index 000000000000..6562bf63afaa
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c
@@ -0,0 +1,261 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/* Copyright (c) 2020 Mellanox Technologies Ltd */
+
+#include <linux/mlx5/driver.h>
+#include <linux/mlx5/device.h>
+#include "mlx5_core.h"
+#include "dev.h"
+#include "sf/vhca_event.h"
+#include "sf/sf.h"
+#include "sf/mlx5_ifc_vhca_event.h"
+#include "ecpf.h"
+
+struct mlx5_sf_dev_table {
+	struct xarray devices;
+	unsigned int max_sfs;
+	phys_addr_t base_address;
+	u64 sf_bar_length;
+	struct notifier_block nb;
+	struct mlx5_core_dev *dev;
+};
+
+static bool mlx5_sf_dev_supported(const struct mlx5_core_dev *dev)
+{
+	return MLX5_CAP_GEN(dev, sf) && mlx5_vhca_event_supported(dev);
+}
+
+static ssize_t sfnum_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct auxiliary_device *adev = container_of(dev, struct auxiliary_device, dev);
+	struct mlx5_sf_dev *sf_dev = container_of(adev, struct mlx5_sf_dev, adev);
+
+	return scnprintf(buf, PAGE_SIZE, "%u\n", sf_dev->sfnum);
+}
+static DEVICE_ATTR_RO(sfnum);
+
+static struct attribute *sf_device_attrs[] = {
+	&dev_attr_sfnum.attr,
+	NULL,
+};
+
+static const struct attribute_group sf_attr_group = {
+	.attrs = sf_device_attrs,
+};
+
+static const struct attribute_group *sf_attr_groups[2] = {
+	&sf_attr_group,
+	NULL
+};
+
+static void mlx5_sf_dev_release(struct device *device)
+{
+	struct auxiliary_device *adev = container_of(device, struct auxiliary_device, dev);
+	struct mlx5_sf_dev *sf_dev = container_of(adev, struct mlx5_sf_dev, adev);
+
+	mlx5_adev_idx_free(adev->id);
+	kfree(sf_dev);
+}
+
+static void mlx5_sf_dev_remove(struct mlx5_sf_dev *sf_dev)
+{
+	auxiliary_device_delete(&sf_dev->adev);
+	auxiliary_device_uninit(&sf_dev->adev);
+}
+
+static void mlx5_sf_dev_add(struct mlx5_core_dev *dev, u16 sf_index, u32 sfnum)
+{
+	struct mlx5_sf_dev_table *table = dev->priv.sf_dev_table;
+	struct mlx5_sf_dev *sf_dev;
+	struct pci_dev *pdev;
+	int err;
+	int id;
+
+	id = mlx5_adev_idx_alloc();
+	if (id < 0) {
+		err = id;
+		goto add_err;
+	}
+
+	sf_dev = kzalloc(sizeof(*sf_dev), GFP_KERNEL);
+	if (!sf_dev) {
+		mlx5_adev_idx_free(id);
+		err = -ENOMEM;
+		goto add_err;
+	}
+	pdev = dev->pdev;
+	sf_dev->adev.id = id;
+	sf_dev->adev.name = MLX5_SF_DEV_ID_NAME;
+	sf_dev->adev.dev.release = mlx5_sf_dev_release;
+	sf_dev->adev.dev.parent = &pdev->dev;
+	sf_dev->adev.dev.groups = sf_attr_groups;
+	sf_dev->sfnum = sfnum;
+	sf_dev->parent_mdev = dev;
+
+	if (!table->max_sfs) {
+		mlx5_adev_idx_free(id);
+		kfree(sf_dev);
+		err = -EOPNOTSUPP;
+		goto add_err;
+	}
+	sf_dev->bar_base_addr = table->base_address + (sf_index * table->sf_bar_length);
+
+	err = auxiliary_device_init(&sf_dev->adev);
+	if (err) {
+		mlx5_adev_idx_free(id);
+		kfree(sf_dev);
+		goto add_err;
+	}
+
+	err = auxiliary_device_add(&sf_dev->adev);
+	if (err) {
+		put_device(&sf_dev->adev.dev);
+		goto add_err;
+	}
+
+	err = xa_insert(&table->devices, sf_index, sf_dev, GFP_KERNEL);
+	if (err)
+		goto xa_err;
+	return;
+
+xa_err:
+	mlx5_sf_dev_remove(sf_dev);
+add_err:
+	mlx5_core_err(dev, "SF DEV: fail device add for index=%d sfnum=%d err=%d\n",
+		      sf_index, sfnum, err);
+}
+
+static void mlx5_sf_dev_del(struct mlx5_core_dev *dev, struct mlx5_sf_dev *sf_dev, u16 sf_index)
+{
+	struct mlx5_sf_dev_table *table = dev->priv.sf_dev_table;
+
+	xa_erase(&table->devices, sf_index);
+	mlx5_sf_dev_remove(sf_dev);
+}
+
+static int
+mlx5_sf_dev_state_change_handler(struct notifier_block *nb, unsigned long event_code, void *data)
+{
+	struct mlx5_sf_dev_table *table = container_of(nb, struct mlx5_sf_dev_table, nb);
+	const struct mlx5_vhca_state_event *event = data;
+	struct mlx5_sf_dev *sf_dev;
+	u16 sf_index;
+
+	sf_index = event->function_id - MLX5_CAP_GEN(table->dev, sf_base_id);
+	sf_dev = xa_load(&table->devices, sf_index);
+	switch (event->new_vhca_state) {
+	case MLX5_VHCA_STATE_TEARDOWN_REQUEST:
+		if (sf_dev)
+			mlx5_sf_dev_del(table->dev, sf_dev, sf_index);
+		else
+			mlx5_core_err(table->dev,
+				      "SF DEV: teardown state for invalid dev index=%d fn_id=0x%x\n",
+				      sf_index, event->sw_function_id);
+		break;
+	case MLX5_VHCA_STATE_ACTIVE:
+		if (!sf_dev)
+			mlx5_sf_dev_add(table->dev, sf_index, event->sw_function_id);
+		break;
+	default:
+		break;
+	}
+	return 0;
+}
+
+static int mlx5_sf_dev_vhca_arm_all(struct mlx5_sf_dev_table *table)
+{
+	struct mlx5_core_dev *dev = table->dev;
+	u16 max_functions;
+	u16 function_id;
+	int err = 0;
+	bool ecpu;
+	int i;
+
+	max_functions = mlx5_sf_max_functions(dev);
+	function_id = MLX5_CAP_GEN(dev, sf_base_id);
+	ecpu = mlx5_read_embedded_cpu(dev);
+	/* Arm the vhca context as the vhca event notifier */
+	for (i = 0; i < max_functions; i++) {
+		err = mlx5_vhca_event_arm(dev, function_id, ecpu);
+		if (err)
+			return err;
+
+		function_id++;
+	}
+	return 0;
+}
+
+void mlx5_sf_dev_table_create(struct mlx5_core_dev *dev)
+{
+	struct mlx5_sf_dev_table *table;
+	unsigned int max_sfs;
+	int err;
+
+	if (!mlx5_sf_dev_supported(dev) || !mlx5_vhca_event_supported(dev))
+		return;
+
+	table = kzalloc(sizeof(*table), GFP_KERNEL);
+	if (!table) {
+		err = -ENOMEM;
+		goto table_err;
+	}
+
+	table->nb.notifier_call = mlx5_sf_dev_state_change_handler;
+	table->dev = dev;
+	if (MLX5_CAP_GEN(dev, max_num_sf))
+		max_sfs = MLX5_CAP_GEN(dev, max_num_sf);
+	else
+		max_sfs = 1 << MLX5_CAP_GEN(dev, log_max_sf);
+	table->sf_bar_length = 1 << (MLX5_CAP_GEN(dev, log_min_sf_size) + 12);
+	table->base_address = pci_resource_start(dev->pdev, 2);
+	table->max_sfs = max_sfs;
+	xa_init(&table->devices);
+	dev->priv.sf_dev_table = table;
+
+	err = mlx5_vhca_event_notifier_register(dev, &table->nb);
+	if (err)
+		goto vhca_err;
+	err = mlx5_sf_dev_vhca_arm_all(table);
+	if (err)
+		goto arm_err;
+	mlx5_core_dbg(dev, "SF DEV: max sf devices=%d\n", max_sfs);
+	return;
+
+arm_err:
+	mlx5_vhca_event_notifier_unregister(dev, &table->nb);
+vhca_err:
+	table->max_sfs = 0;
+	kfree(table);
+	dev->priv.sf_dev_table = NULL;
+table_err:
+	mlx5_core_err(dev, "SF DEV table create err = %d\n", err);
+}
+
+static void mlx5_sf_dev_destroy_all(struct mlx5_sf_dev_table *table)
+{
+	struct mlx5_sf_dev *sf_dev;
+	unsigned long index;
+
+	xa_for_each(&table->devices, index, sf_dev) {
+		xa_erase(&table->devices, index);
+		mlx5_sf_dev_remove(sf_dev);
+	}
+}
+
+void mlx5_sf_dev_table_destroy(struct mlx5_core_dev *dev)
+{
+	struct mlx5_sf_dev_table *table = dev->priv.sf_dev_table;
+
+	if (!table)
+		return;
+
+	mlx5_vhca_event_notifier_unregister(dev, &table->nb);
+
+	/* Now that event handler is not running, it is safe to destroy
+	 * the sf device without race.
+	 */
+	mlx5_sf_dev_destroy_all(table);
+
+	WARN_ON(!xa_empty(&table->devices));
+	kfree(table);
+	dev->priv.sf_dev_table = NULL;
+}
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.h b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.h
new file mode 100644
index 000000000000..a6fb7289ba2c
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/* Copyright (c) 2020 Mellanox Technologies Ltd */
+
+#ifndef __MLX5_SF_DEV_H__
+#define __MLX5_SF_DEV_H__
+
+#ifdef CONFIG_MLX5_SF
+
+#include <linux/auxiliary_bus.h>
+
+#define MLX5_SF_DEV_ID_NAME "sf"
+
+struct mlx5_sf_dev {
+	struct auxiliary_device adev;
+	struct mlx5_core_dev *parent_mdev;
+	phys_addr_t bar_base_addr;
+	u32 sfnum;
+};
+
+void mlx5_sf_dev_table_create(struct mlx5_core_dev *dev);
+void mlx5_sf_dev_table_destroy(struct mlx5_core_dev *dev);
+
+#else
+
+static inline void mlx5_sf_dev_table_create(struct mlx5_core_dev *dev)
+{
+}
+
+static inline void mlx5_sf_dev_table_destroy(struct mlx5_core_dev *dev)
+{
+}
+
+#endif
+
+#endif
diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h
index ffba0786051e..08e5fbe97df0 100644
--- a/include/linux/mlx5/driver.h
+++ b/include/linux/mlx5/driver.h
@@ -508,6 +508,7 @@ struct mlx5_fw_reset;
 struct mlx5_eq_table;
 struct mlx5_irq_table;
 struct mlx5_vhca_state_notifier;
+struct mlx5_sf_dev_table;
 
 struct mlx5_rate_limit {
 	u32			rate;
@@ -606,6 +607,7 @@ struct mlx5_priv {
 	struct mlx5_uars_page	       *uar;
 #ifdef CONFIG_MLX5_SF
 	struct mlx5_vhca_state_notifier *vhca_state_notifier;
+	struct mlx5_sf_dev_table *sf_dev_table;
 #endif
 };
 
