diff --git a/sys/arm/broadcom/bcm2835/bcm2835_bsc.c b/sys/arm/broadcom/bcm2835/bcm2835_bsc.c
index 3e1afcd0238f..debbf82cb2f1 100644
--- a/sys/arm/broadcom/bcm2835/bcm2835_bsc.c
+++ b/sys/arm/broadcom/bcm2835/bcm2835_bsc.c
@@ -247,7 +247,7 @@ bcm_bsc_attach(device_t dev)
 	/* Check the unit we are attaching by its base address. */
 	start = rman_get_start(sc->sc_mem_res);
 	for (i = 0; i < nitems(bcm_bsc_pins); i++) {
-		if (bcm_bsc_pins[i].start == start)
+		if (bcm_bsc_pins[i].start == (start & BCM_BSC_BASE_MASK))
 			break;
 	}
 	if (i == nitems(bcm_bsc_pins)) {
diff --git a/sys/arm/broadcom/bcm2835/bcm2835_bscvar.h b/sys/arm/broadcom/bcm2835/bcm2835_bscvar.h
index 5068356489f3..6b31dc3cc7a0 100644
--- a/sys/arm/broadcom/bcm2835/bcm2835_bscvar.h
+++ b/sys/arm/broadcom/bcm2835/bcm2835_bscvar.h
@@ -35,9 +35,10 @@ struct {
 	uint32_t	scl;
 	unsigned long	start;
 } bcm_bsc_pins[] = {
-	{ 0, 1, 0x20205000 },	/* BSC0 GPIO pins and base address. */
-	{ 2, 3, 0x20804000 }	/* BSC1 GPIO pins and base address. */
+	{ 0, 1, 0x205000 },	/* BSC0 GPIO pins and base address. */
+	{ 2, 3, 0x804000 }	/* BSC1 GPIO pins and base address. */
 };
+#define	BCM_BSC_BASE_MASK	0x00ffffff
 
 struct bcm_bsc_softc {
 	device_t		sc_dev;