diff --git a/arch/ppc64/xmon/start.c b/arch/ppc64/xmon/start.c
index f86b584acd76d16793e55be30848319d3e7066de..93bf8cb0a76266c582fe5e5925803eb988a4557a 100644
--- a/arch/ppc64/xmon/start.c
+++ b/arch/ppc64/xmon/start.c
@@ -61,7 +61,9 @@ xmon_read(void *handle, void *ptr, int nb)
 int
 xmon_read_poll(void)
 {
-	return udbg_getc_poll();
+	if (ppc_md.udbg_getc_poll)
+		return ppc_md.udbg_getc_poll();
+	return -1;
 }
  
 FILE *xmon_stdin;