diff --git a/drivers/clocksource/cyclone.c b/drivers/clocksource/cyclone.c
index 72f811f73e9..9e0998f2288 100644
--- a/drivers/clocksource/cyclone.c
+++ b/drivers/clocksource/cyclone.c
@@ -55,11 +55,11 @@ static int __init init_cyclone_clocksource(void)
 	}
 	/* even on 64bit systems, this is only 32bits: */
 	base = readl(reg);
+	iounmap(reg);
 	if (!base) {
 		printk(KERN_ERR "Summit chipset: Could not find valid CBAR value.\n");
 		return -ENODEV;
 	}
-	iounmap(reg);
 
 	/* setup PMCC: */
 	offset = base + CYCLONE_PMCC_OFFSET;