diff --git a/tools/testing/selftests/powerpc/primitives/load_unaligned_zeropad.c b/tools/testing/selftests/powerpc/primitives/load_unaligned_zeropad.c
index d1b647509596..6cae06117b55 100644
--- a/tools/testing/selftests/powerpc/primitives/load_unaligned_zeropad.c
+++ b/tools/testing/selftests/powerpc/primitives/load_unaligned_zeropad.c
@@ -25,10 +25,19 @@
 
 #define FIXUP_SECTION ".ex_fixup"
 
+static inline unsigned long __fls(unsigned long x);
+
 #include "word-at-a-time.h"
 
 #include "utils.h"
 
+static inline unsigned long __fls(unsigned long x)
+{
+	int lz;
+
+	asm (PPC_CNTLZL "%0,%1" : "=r" (lz) : "r" (x));
+	return sizeof(unsigned long) - 1 - lz;
+}
 
 static int page_size;
 static char *mem_region;