diff --git a/yotta/data/target_config.h b/yotta/data/target_config.h
new file mode 100644
index 0000000..02af2b3
--- /dev/null
+++ b/yotta/data/target_config.h
@@ -0,0 +1,22 @@
+/*
+ *  Temporary target-specific config.h for entropy collection
+ *
+ *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ *
+ *  This file is part of mbed TLS (https://tls.mbed.org)
+ */
+
+#if defined(TARGET_LIKE_MBED)
+#define MBEDTLS_NO_PLATFORM_ENTROPY
+#undef MBEDTLS_HAVE_TIME_DATE
+#undef MBEDTLS_FS_IO
+#endif
+
+/*
+ * WARNING: this is a temporary hack!
+ * 2. This should be in a separete yotta module which would be a target
+ * dependency of mbedtls (see IOTSSL-313)
+ */
+#if defined(TARGET_LIKE_CORTEX_M4)
+#define MBEDTLS_ENTROPY_HARDWARE_ALT
+#endif