diff --git a/include/lib/utils_def.h b/include/lib/utils_def.h
index 185a1c1..bda3b07 100644
--- a/include/lib/utils_def.h
+++ b/include/lib/utils_def.h
@@ -16,7 +16,7 @@
 
 #define SIZE_FROM_LOG2_WORDS(n)		(4 << (n))
 
-#define BIT(nr)				(1ULL << (nr))
+#define BIT(nr)				(ULL(1) << (nr))
 
 /*
  * This variant of div_round_up can be used in macro definition but should not
@@ -84,6 +84,13 @@
 # define ULL(_x)	(_x##ull)
 #endif
 
+/* Register size of the current architecture. */
+#ifdef AARCH32
+#define REGSZ		U(4)
+#else
+#define REGSZ		U(8)
+#endif
+
 /*
  * Test for the current architecture version to be at least the version
  * expected.