diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h
index 31beddede0f2..efa7c08d842a 100644
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -233,6 +233,7 @@ struct nsim_dev {
 		struct list_head head;
 		struct ida ida;
 		struct ida pfnum_ida;
+		struct ida sfnum_ida;
 		struct mutex disable_mutex; /* protects port deletion
 					     * by driver unload context
 					     */
diff --git a/drivers/net/netdevsim/port_function.c b/drivers/net/netdevsim/port_function.c
index 7df1ca5ad7b8..86607d574930 100644
--- a/drivers/net/netdevsim/port_function.c
+++ b/drivers/net/netdevsim/port_function.c
@@ -9,9 +9,12 @@
 struct nsim_port_fn {
 	struct devlink_port dl_port;
 	struct net_device *netdev;
+	struct nsim_port_fn *pf_pfn;
 	struct list_head list;
 	unsigned int port_index;
 	enum devlink_port_flavour flavour;
+	int refcount; /* Counts how many sf ports are bound attached to this pf port. */
+	u32 sfnum;
 	u16 pfnum;
 };
 
@@ -91,9 +94,24 @@ nsim_devlink_port_fn_alloc(struct nsim_dev *dev,
 			goto fn_ida_err;
 		port->pfnum = ret;
 		break;
+	case DEVLINK_PORT_FLAVOUR_PCI_SF:
+		if (attrs->sfnum_valid)
+			ret = ida_alloc_range(&dev->port_functions.sfnum_ida, attrs->sfnum,
+					      attrs->sfnum, GFP_KERNEL);
+		else
+			ret = ida_alloc(&dev->port_functions.sfnum_ida, GFP_KERNEL);
+		if (ret < 0)
+			goto fn_ida_err;
+		port->sfnum = ret;
+		port->pfnum = attrs->pfnum;
+		break;
 	default:
 		break;
 	}
+	/* refcount_t is not needed as port is protected by port_functions.mutex.
+	 * This count is to keep track of how many SF ports are attached a PF port.
+	 */
+	port->refcount = 1;
 	return port;
 
 fn_ida_err:
@@ -110,6 +128,9 @@ nsim_devlink_port_fn_free(struct nsim_dev *dev, struct nsim_port_fn *port)
 	case DEVLINK_PORT_FLAVOUR_PCI_PF:
 		ida_simple_remove(&dev->port_functions.pfnum_ida, port->pfnum);
 		break;
+	case DEVLINK_PORT_FLAVOUR_PCI_SF:
+		ida_simple_remove(&dev->port_functions.sfnum_ida, port->sfnum);
+		break;
 	default:
 		break;
 	}
@@ -139,6 +160,12 @@ nsim_dev_port_port_exists(struct nsim_dev *nsim_dev,
 		    tmp->flavour == DEVLINK_PORT_FLAVOUR_PCI_PF &&
 		    tmp->pfnum == attrs->pfnum)
 			return true;
+
+		if (attrs->flavour == DEVLINK_PORT_FLAVOUR_PCI_SF &&
+		    tmp->flavour == DEVLINK_PORT_FLAVOUR_PCI_SF &&
+		    attrs->sfnum_valid &&
+		    tmp->sfnum == attrs->sfnum && tmp->pfnum == attrs->pfnum)
+			return true;
 	}
 	return false;
 }
@@ -153,20 +180,72 @@ nsim_dev_devlink_port_index_lookup(const struct nsim_dev *nsim_dev,
 	list_for_each_entry(port, &nsim_dev->port_functions.head, list) {
 		if (port->port_index != port_index)
 			continue;
+		if (port->refcount > 1) {
+			NL_SET_ERR_MSG_MOD(extack, "Port is in use");
+			return ERR_PTR(-EBUSY);
+		}
 		return port;
 	}
 	NL_SET_ERR_MSG_MOD(extack, "User created port not found");
 	return ERR_PTR(-ENOENT);
 }
 
+static struct nsim_port_fn *
+pf_port_get(struct nsim_dev *nsim_dev, struct nsim_port_fn *port)
+{
+	struct nsim_port_fn *tmp;
+
+	/* PF port addition doesn't need a parent. */
+	if (port->flavour == DEVLINK_PORT_FLAVOUR_PCI_PF)
+		return NULL;
+
+	list_for_each_entry(tmp, &nsim_dev->port_functions.head, list) {
+		if (tmp->flavour != DEVLINK_PORT_FLAVOUR_PCI_PF ||
+		    tmp->pfnum != port->pfnum)
+			continue;
+
+		if (tmp->refcount + 1 == INT_MAX)
+			return ERR_PTR(-ENOSPC);
+
+		port->pf_pfn = tmp;
+		tmp->refcount++;
+		return tmp;
+	}
+	return ERR_PTR(-ENOENT);
+}
+
+static void pf_port_put(struct nsim_port_fn *port)
+{
+	if (port->pf_pfn) {
+		port->pf_pfn->refcount--;
+		WARN_ON(port->pf_pfn->refcount < 0);
+	}
+	port->refcount--;
+	WARN_ON(port->refcount != 0);
+}
+
 static int nsim_devlink_port_fn_add(struct devlink *devlink,
 				    struct nsim_dev *nsim_dev,
 				    struct nsim_port_fn *port,
 				    struct netlink_ext_ack *extack)
 {
+	struct nsim_port_fn *pf_pfn;
 	int err;
 
-	list_add(&port->list, &nsim_dev->port_functions.head);
+	/* Keep all PF ports at the start, so that when driver is unloaded
+	 * All SF ports from the end of the list can be removed first.
+	 */
+	if (port->flavour == DEVLINK_PORT_FLAVOUR_PCI_PF)
+		list_add(&port->list, &nsim_dev->port_functions.head);
+	else
+		list_add_tail(&port->list, &nsim_dev->port_functions.head);
+
+	pf_pfn = pf_port_get(nsim_dev, port);
+	if (IS_ERR(pf_pfn)) {
+		NL_SET_ERR_MSG_MOD(extack, "Fail to get pf port");
+		err = PTR_ERR(pf_pfn);
+		goto pf_err;
+	}
 
 	err = devlink_port_register(devlink, &port->dl_port, port->port_index);
 	if (err)
@@ -183,6 +262,8 @@ static int nsim_devlink_port_fn_add(struct devlink *devlink,
 	devlink_port_type_clear(&port->dl_port);
 	devlink_port_unregister(&port->dl_port);
 reg_err:
+	pf_port_put(port);
+pf_err:
 	list_del(&port->list);
 	return err;
 }
@@ -194,13 +275,15 @@ static void nsim_devlink_port_fn_del(struct nsim_dev *nsim_dev,
 	unregister_netdev(port->netdev);
 	devlink_port_unregister(&port->dl_port);
 	list_del(&port->list);
+	pf_port_put(port);
 }
 
 static bool
 nsim_dev_port_flavour_supported(const struct nsim_dev *nsim_dev,
 				const struct devlink_port_new_attrs *attrs)
 {
-	return attrs->flavour == DEVLINK_PORT_FLAVOUR_PCI_PF;
+	return attrs->flavour == DEVLINK_PORT_FLAVOUR_PCI_PF ||
+	       attrs->flavour == DEVLINK_PORT_FLAVOUR_PCI_SF;
 }
 
 int nsim_dev_devlink_port_new(struct devlink *devlink,
@@ -245,7 +328,12 @@ int nsim_dev_devlink_port_new(struct devlink *devlink,
 	       nsim_dev->switch_id.id_len);
 	port->dl_port.attrs.switch_id.id_len = nsim_dev->switch_id.id_len;
 
-	devlink_port_attrs_pci_pf_set(&port->dl_port, 0, port->pfnum, false);
+	if (attrs->flavour == DEVLINK_PORT_FLAVOUR_PCI_PF)
+		devlink_port_attrs_pci_pf_set(&port->dl_port, 0,
+					      port->pfnum, false);
+	else
+		devlink_port_attrs_pci_sf_set(&port->dl_port, 0, port->pfnum,
+					      port->sfnum);
 
 	err = nsim_devlink_port_fn_add(devlink, nsim_dev, port, extack);
 	if (err)
@@ -300,10 +388,13 @@ void nsim_dev_port_fn_init(struct nsim_dev *nsim_dev)
 	INIT_LIST_HEAD(&nsim_dev->port_functions.head);
 	ida_init(&nsim_dev->port_functions.ida);
 	ida_init(&nsim_dev->port_functions.pfnum_ida);
+	ida_init(&nsim_dev->port_functions.sfnum_ida);
 }
 
 void nsim_dev_port_fn_exit(struct nsim_dev *nsim_dev)
 {
+	WARN_ON(!ida_is_empty(&nsim_dev->port_functions.sfnum_ida));
+	ida_destroy(&nsim_dev->port_functions.sfnum_ida);
 	WARN_ON(!ida_is_empty(&nsim_dev->port_functions.pfnum_ida));
 	ida_destroy(&nsim_dev->port_functions.pfnum_ida);
 	WARN_ON(!ida_is_empty(&nsim_dev->port_functions.ida));
@@ -332,6 +423,8 @@ void nsim_dev_port_fn_disable(struct nsim_dev *nsim_dev)
 	 * commands have completed, so it is safe to delete all user created
 	 * ports.
 	 */
+
+	/* Remove SF ports first, followed by PF ports. */
 	list_for_each_entry_safe_reverse(port, tmp,
 					 &nsim_dev->port_functions.head, list) {
 		nsim_devlink_port_fn_del(nsim_dev, port);
