diff --git a/doc/uImage.FIT/source_file_format.txt b/doc/uImage.FIT/source_file_format.txt
index 1e30d22..157936e 100644
--- a/doc/uImage.FIT/source_file_format.txt
+++ b/doc/uImage.FIT/source_file_format.txt
@@ -169,7 +169,7 @@
   - os : OS name, mandatory for type="kernel", valid OS names are: "openbsd",
     "netbsd", "freebsd", "4_4bsd", "linux", "svr4", "esix", "solaris", "irix",
     "sco", "dell", "ncr", "lynxos", "vxworks", "psos", "qnx", "u_boot",
-    "rtems", "unity".
+    "rtems", "unity", "integrity".
   - arch : Architecture name, mandatory for types: "standalone", "kernel",
     "firmware", "ramdisk" and "fdt". Valid architecture names are: "alpha",
     "arm", "i386", "ia64", "mips", "mips64", "ppc", "s390", "sh", "sparc",