diff --git a/lib/time.c b/lib/time.c
index 68b8ff4..6514835 100644
--- a/lib/time.c
+++ b/lib/time.c
@@ -8,6 +8,10 @@
 #include <common.h>
 #include <watchdog.h>
 
+#if CONFIG_SYS_HZ != 1000
+#warning "CONFIG_SYS_HZ must be 1000 and should not be defined by platforms"
+#endif
+
 #ifndef CONFIG_WD_PERIOD
 # define CONFIG_WD_PERIOD	(10 * 1000 * 1000)	/* 10 seconds default*/
 #endif