diff --git a/plat/arm/board/fvp/drivers/pwrc/fvp_pwrc.h b/plat/arm/board/fvp/drivers/pwrc/fvp_pwrc.h
index 5b755af..3dc9aad 100644
--- a/plat/arm/board/fvp/drivers/pwrc/fvp_pwrc.h
+++ b/plat/arm/board/fvp/drivers/pwrc/fvp_pwrc.h
@@ -48,7 +48,8 @@
 #define PSYSR_PP		(1 << 26)
 
 #define PSYSR_WK_SHIFT		24
-#define PSYSR_WK_MASK		0x3
+#define PSYSR_WK_WIDTH		0x2
+#define PSYSR_WK_MASK		((1 << PSYSR_WK_WIDTH) - 1)
 #define PSYSR_WK(x)		(x >> PSYSR_WK_SHIFT) & PSYSR_WK_MASK
 
 #define WKUP_COLD		0x0