diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index 849af9d21fe..3ae497422db 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -2903,6 +2903,7 @@ static int __devinit serial8250_probe(struct platform_device *dev)
 		port.mapbase		= p->mapbase;
 		port.hub6		= p->hub6;
 		port.private_data	= p->private_data;
+		port.type		= p->type;
 		port.serial_in		= p->serial_in;
 		port.serial_out		= p->serial_out;
 		port.dev		= &dev->dev;
@@ -3058,6 +3059,14 @@ int serial8250_register_port(struct uart_port *port)
 		uart->port.private_data = port->private_data;
 		if (port->dev)
 			uart->port.dev = port->dev;
+
+		if (port->flags & UPF_FIXED_TYPE) {
+			uart->port.type = port->type;
+			uart->port.fifosize = uart_config[port->type].fifo_size;
+			uart->capabilities = uart_config[port->type].flags;
+			uart->tx_loadsz = uart_config[port->type].tx_loadsz;
+		}
+
 		set_io_from_upio(&uart->port);
 		/* Possibly override default I/O functions.  */
 		if (port->serial_in)
diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index 9425ed69e0f..dc68b7e0c93 100644
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -2179,11 +2179,14 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state,
 	 * Now do the auto configuration stuff.  Note that config_port
 	 * is expected to claim the resources and map the port for us.
 	 */
-	flags = UART_CONFIG_TYPE;
+	flags = 0;
 	if (port->flags & UPF_AUTO_IRQ)
 		flags |= UART_CONFIG_IRQ;
 	if (port->flags & UPF_BOOT_AUTOCONF) {
-		port->type = PORT_UNKNOWN;
+		if (!(port->flags & UPF_FIXED_TYPE)) {
+			port->type = PORT_UNKNOWN;
+			flags |= UART_CONFIG_TYPE;
+		}
 		port->ops->config_port(port, flags);
 	}
 
diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
index 77d83d929f2..d4d2a78ad43 100644
--- a/include/linux/serial_8250.h
+++ b/include/linux/serial_8250.h
@@ -28,6 +28,7 @@ struct plat_serial8250_port {
 	unsigned char	iotype;		/* UPIO_* */
 	unsigned char	hub6;
 	upf_t		flags;		/* UPF_* flags */
+	unsigned int	type;		/* If UPF_FIXED_TYPE */
 	unsigned int	(*serial_in)(struct uart_port *, int);
 	void		(*serial_out)(struct uart_port *, int, int);
 };
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 60061f44f3d..f155252f148 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -295,6 +295,8 @@ struct uart_port {
 #define UPF_MAGIC_MULTIPLIER	((__force upf_t) (1 << 16))
 #define UPF_CONS_FLOW		((__force upf_t) (1 << 23))
 #define UPF_SHARE_IRQ		((__force upf_t) (1 << 24))
+/* The exact UART type is known and should not be probed.  */
+#define UPF_FIXED_TYPE		((__force upf_t) (1 << 27))
 #define UPF_BOOT_AUTOCONF	((__force upf_t) (1 << 28))
 #define UPF_FIXED_PORT		((__force upf_t) (1 << 29))
 #define UPF_DEAD		((__force upf_t) (1 << 30))