diff --git a/hw/char/pl011.c b/hw/char/pl011.c
index 15df7c1e1c..0fd1334fab 100644
--- a/hw/char/pl011.c
+++ b/hw/char/pl011.c
@@ -90,10 +90,10 @@ DeviceState *pl011_create(hwaddr addr, qemu_irq irq, Chardev *chr)
 #define CR_UARTEN   (1 << 0)
 
 /* Integer Baud Rate Divider, UARTIBRD */
-#define IBRD_MASK 0x3f
+#define IBRD_MASK 0xffff
 
 /* Fractional Baud Rate Divider, UARTFBRD */
-#define FBRD_MASK 0xffff
+#define FBRD_MASK 0x3f
 
 static const unsigned char pl011_id_arm[8] =
   { 0x11, 0x10, 0x14, 0x00, 0x0d, 0xf0, 0x05, 0xb1 };