diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index f977c98cfa95..308588e2072b 100644
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -2154,12 +2154,11 @@ uart_report_port(struct uart_driver *drv, struct uart_port *port)
 
 	switch (port->iotype) {
 	case UPIO_PORT:
-		snprintf(address, sizeof(address),
-			 "I/O 0x%x", port->iobase);
+		snprintf(address, sizeof(address), "I/O 0x%lx", port->iobase);
 		break;
 	case UPIO_HUB6:
 		snprintf(address, sizeof(address),
-			 "I/O 0x%x offset 0x%x", port->iobase, port->hub6);
+			 "I/O 0x%lx offset 0x%x", port->iobase, port->hub6);
 		break;
 	case UPIO_MEM:
 	case UPIO_MEM32: