diff --git a/rtemsbsd/freebsd/sys/limits.h b/rtemsbsd/freebsd/sys/limits.h
new file mode 100644
index 00000000..b2850e20
--- /dev/null
+++ b/rtemsbsd/freebsd/sys/limits.h
@@ -0,0 +1,9 @@
+#include <sys/types.h>
+#include <limits.h>
+
+#define __FD_SETSIZE 1024
+#define FD_SETSIZE __FD_SETSIZE
+
+#define __CHAR_BIT     CHAR_BIT               /* number of bits in a char */
+
+
diff --git a/rtemsbsd/freebsd/sys/timespec.h b/rtemsbsd/freebsd/sys/timespec.h
new file mode 100644
index 00000000..4ec4147e
--- /dev/null
+++ b/rtemsbsd/freebsd/sys/timespec.h
@@ -0,0 +1,10 @@
+#define TIMEVAL_TO_TIMESPEC(tv, ts)                                     \
+        do {                                                            \
+                (ts)->tv_sec = (tv)->tv_sec;                            \
+                (ts)->tv_nsec = (tv)->tv_usec * 1000;                   \
+        } while (0)
+#define TIMESPEC_TO_TIMEVAL(tv, ts)                                     \
+        do {                                                            \
+                (tv)->tv_sec = (ts)->tv_sec;                            \
+                (tv)->tv_usec = (ts)->tv_nsec / 1000;                   \
+        } while (0)