diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h
index 0ea9705eda38..c70782e444d5 100644
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -222,6 +222,7 @@ struct nsim_dev {
 		struct list_head head;
 		struct ida ida;
 		struct ida pfnum_ida;
+		struct ida sfnum_ida;
 	} port_functions;
 };
 
diff --git a/drivers/net/netdevsim/port_function.c b/drivers/net/netdevsim/port_function.c
index 99581d3d15fe..e1812acd55b4 100644
--- a/drivers/net/netdevsim/port_function.c
+++ b/drivers/net/netdevsim/port_function.c
@@ -13,10 +13,12 @@ struct nsim_port_function {
 	unsigned int port_index;
 	enum devlink_port_flavour flavour;
 	u32 controller;
+	u32 sfnum;
 	u16 pfnum;
 	struct nsim_port_function *pf_port; /* Valid only for SF port */
 	u8 hw_addr[ETH_ALEN];
 	u8 state; /* enum devlink_port_function_state */
+	int refcount; /* Counts how many sf ports are bound attached to this pf port. */
 };
 
 void nsim_dev_port_function_init(struct nsim_dev *nsim_dev)
@@ -25,10 +27,13 @@ void nsim_dev_port_function_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_function_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));
@@ -119,9 +124,24 @@ nsim_devlink_port_function_alloc(struct nsim_dev *dev, const struct devlink_port
 			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:
@@ -137,6 +157,9 @@ static void nsim_devlink_port_function_free(struct nsim_dev *dev, struct nsim_po
 	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;
 	}
@@ -170,6 +193,11 @@ nsim_dev_port_port_exists(struct nsim_dev *nsim_dev, const struct devlink_port_n
 		if (attrs->flavour == DEVLINK_PORT_FLAVOUR_PCI_PF &&
 		    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 &&
+		    tmp->sfnum == attrs->sfnum && tmp->pfnum == attrs->pfnum)
+			return true;
 	}
 	return false;
 }
@@ -183,21 +211,71 @@ nsim_dev_devlink_port_index_lookup(const struct nsim_dev *nsim_dev, unsigned int
 	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_function *
+pf_port_get(struct nsim_dev *nsim_dev, struct nsim_port_function *port)
+{
+	struct nsim_port_function *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_port = tmp;
+		tmp->refcount++;
+		return tmp;
+	}
+	return ERR_PTR(-ENOENT);
+}
+
+static void pf_port_put(struct nsim_port_function *port)
+{
+	if (port->pf_port) {
+		port->pf_port->refcount--;
+		WARN_ON(port->pf_port->refcount < 0);
+	}
+	port->refcount--;
+	WARN_ON(port->refcount != 0);
+}
+
 static int nsim_devlink_port_function_add(struct devlink *devlink, struct nsim_dev *nsim_dev,
 					  struct nsim_port_function *port,
 					  struct netlink_ext_ack *extack)
 {
+	struct nsim_port_function *pf_port;
 	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_port = pf_port_get(nsim_dev, port);
+	if (IS_ERR(pf_port)) {
+		NL_SET_ERR_MSG_MOD(extack, "Fail to get pf port");
+		err = PTR_ERR(pf_port);
+		goto pf_err;
+	}
 
-	port->state = DEVLINK_PORT_FUNCTION_STATE_INACTIVE;
 	err = devlink_port_register(devlink, &port->dl_port, port->port_index);
 	if (err)
 		goto reg_err;
@@ -213,6 +291,8 @@ static int nsim_devlink_port_function_add(struct devlink *devlink, struct nsim_d
 	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;
 }
@@ -224,12 +304,14 @@ static void nsim_devlink_port_function_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, const struct devlink_port_new_attrs *attrs,
@@ -266,7 +348,11 @@ int nsim_dev_devlink_port_new(struct devlink *devlink, const struct devlink_port
 	       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, port->controller, port->pfnum, false);
+	if (attrs->flavour == DEVLINK_PORT_FLAVOUR_PCI_PF)
+		devlink_port_attrs_pci_pf_set(&port->dl_port, port->controller, port->pfnum, false);
+	else
+		devlink_port_attrs_pci_sf_set(&port->dl_port, port->controller, port->pfnum,
+					      port->sfnum, false);
 
 	err = nsim_devlink_port_function_add(devlink, nsim_dev, port, extack);
 	if (err)
@@ -333,6 +419,7 @@ void nsim_dev_port_function_disable(struct nsim_dev *nsim_dev)
 	 * 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_function_del(nsim_dev, port);
 		nsim_devlink_port_function_free(nsim_dev, port);
