diff --git a/libports/lib/mk/libc_ffat.mk b/libports/lib/mk/libc_ffat.mk
index ad229671e..97860154d 100644
--- a/libports/lib/mk/libc_ffat.mk
+++ b/libports/lib/mk/libc_ffat.mk
@@ -1,3 +1,9 @@
+FFAT_DIR = $(REP_DIR)/contrib/ff007e
+
+ifeq ($(wildcard $(FFAT_DIR)),)
+REQUIRES += prepare_ffat
+endif
+
 SRC_CC = plugin.cc
 LIBS  += libc ffat_block