diff --git a/include/config_fallbacks.h b/include/config_fallbacks.h
index 81cbad4..46dfccb 100644
--- a/include/config_fallbacks.h
+++ b/include/config_fallbacks.h
@@ -57,4 +57,8 @@
 #define CONFIG_SYS_PROMPT	"=> "
 #endif
 
+#ifndef CONFIG_SYS_HZ
+#define CONFIG_SYS_HZ		1000
+#endif
+
 #endif	/* __CONFIG_FALLBACKS_H */
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