diff --git a/build/configs/armvirt_defconfig b/build/configs/armvirt_defconfig
index 4bd48ac..d320211 100644
--- a/build/configs/armvirt_defconfig
+++ b/build/configs/armvirt_defconfig
@@ -2,10 +2,15 @@
 
 CONFIG_ARCH = arm
 CONFIG_PLAT = armvirt
-CONFIG_ARCH_VER = armv6k
+CONFIG_ARCH_VER = armv7-a
 
 CONFIG_DEBUG = y
 CONFIG_VERBOSE = y
 
 CONFIG_UART = y
-CONFIG_ARMVIRT_UART = y
+CONFIG_PL011_UART = y
+
+CONFIG_LOADER_MENU = y
+CONFIG_YMODEM = y
+CONFIG_KERMIT = y
+CONFIG_OS_RAM_ADDR = 0x40200000
diff --git a/core/init.c b/core/init.c
index 9ca684a..ad76875 100644
--- a/core/init.c
+++ b/core/init.c
@@ -8,7 +8,6 @@
 #include <init.h>
 #include <uart/uart.h>
 
-#ifdef CONFIG_DEFAULT_LOADER
 extern struct loader_opt g_loader_begin[], g_loader_end[];
 
 static inline void boot(struct loader_opt *loader)
@@ -48,7 +47,6 @@ static int load_os(char key)
 
 	return 0;
 }
-#endif
 
 static const char __init_data banner[] = "\ng-bios " __GBIOS_VER__
 #ifdef CONFIG_VERBOSE
@@ -115,7 +113,7 @@ int main(void)
 	for (;;) {
 #endif
 
-#if 0
+#if 1
 		char key;
 
 		if (uart_rxbuf_count() > 0) {
diff --git a/driver/uart/Makefile b/driver/uart/Makefile
index ae6c5f9..d7c17d4 100644
--- a/driver/uart/Makefile
+++ b/driver/uart/Makefile
@@ -7,4 +7,4 @@ obj-$(CONFIG_UART_AT91)   += at91_uart.o
 obj-$(CONFIG_UART_OMAP3)  += omap3_uart.o
 obj-$(CONFIG_UART_OMAP4)  += omap4_uart.o
 obj-$(CONFIG_E310_UART)   += e310_uart.o
-obj-$(CONFIG_ARMVIRT_UART)   += armvirt_uart.o
+obj-$(CONFIG_PL011_UART)  += pl011_uart.o
diff --git a/driver/uart/armvirt_uart.c b/driver/uart/armvirt_uart.c
deleted file mode 100644
index 6cc4a7c..0000000
--- a/driver/uart/armvirt_uart.c
+++ /dev/null
@@ -1,32 +0,0 @@
-#include <io.h>
-#include <init.h>
-#include <uart/uart.h>
-
-#define ARMVIRT_UART_BASE 0x09000000
-
-static __init int armvirt_uart_init(void)
-{
-    return 0;
-}
-
-void __io_putchar(__u8 b)
-{
-    // TODO: check FIFO
-    writeb(VA(ARMVIRT_UART_BASE), b);
-}
-
-stdio_init(armvirt_uart_init);
-
-void uart_send_byte(__u8 b)
-{
-    writeb(VA(ARMVIRT_UART_BASE), b);
-}
-__u8 uart_recv_byte()
-{
-    return readb(VA(ARMVIRT_UART_BASE));
-}
-
-__u32 uart_rxbuf_count()
-{
-    return 0;
-}
diff --git a/driver/uart/pl011_uart.c b/driver/uart/pl011_uart.c
new file mode 100644
index 0000000..4e4ef4b
--- /dev/null
+++ b/driver/uart/pl011_uart.c
@@ -0,0 +1,44 @@
+#include <io.h>
+#include <init.h>
+#include <uart/uart.h>
+
+#define PL011_UART_BASE 0x09000000
+
+#define UART_DR       0x00
+#define UART_RSRECR   0x04
+#define UART_FR       0x18
+#define UART_ILPR     0x20
+#define UART_IBRD     0x24
+#define UART_FBRD     0x28
+#define UART_LCR_H    0x2C
+#define UART_CR       0x30
+
+// #define UART_FR_BUSY  (1 << 3)  // UART is busy?
+#define UART_FR_RXFE  (1 << 4)  // RX FIFO is empty
+#define UART_FR_TXFF  (1 << 5)  // TX FIFO is full
+
+#define UART_READB(reg) \
+	readb(VA(PL011_UART_BASE + (reg)))
+
+#define UART_WRITEB(reg, val) \
+	writeb(VA(PL011_UART_BASE + (reg)), (val))
+static __init int pl011_uart_init(void)
+{
+    return 0;
+}
+
+stdio_init(pl011_uart_init);
+
+void uart_send_byte(__u8 b)
+{
+    UART_WRITEB(UART_DR, b);
+}
+__u8 uart_recv_byte()
+{
+    return UART_READB(UART_DR);
+}
+
+__u32 uart_rxbuf_count()
+{
+    return UART_READB(UART_FR) & UART_FR_RXFE;
+}