diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index 5a5645a..91503b8 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -1169,7 +1169,8 @@
 	}
 
 	gd->ram_size = (phys_size_t)(res.end - res.start + 1);
-	debug("%s: Initial DRAM size %llx\n", __func__, (u64)gd->ram_size);
+	debug("%s: Initial DRAM size %llx\n", __func__,
+	      (unsigned long long)gd->ram_size);
 
 	return 0;
 }