diff --git a/lib/tiny-printf.c b/lib/tiny-printf.c
index faf55d7f327..da2063d27c9 100644
--- a/lib/tiny-printf.c
+++ b/lib/tiny-printf.c
@@ -285,6 +285,7 @@ static int _vprintf(struct printf_info *info, const char *fmt, va_list va)
 				islong = true;
 				/* no break */
 			case 'x':
+			case 'X':
 				if (islong) {
 					num = va_arg(va, unsigned long);
 					div = 1UL << (sizeof(long) * 8 - 4);