Add license, readme and dco files
Signed-off-by: David Wang <david.wang@arm.com>
Change-Id: I5f048985ac4a0d32f27d100f4af1a6c0375cb54e
diff --git a/readme.rst b/readme.rst
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+#########################
+Trusted Firmware-M Extras
+#########################
+
+The Trusted Firmware-M (TF-M) Extras repository is the extension of the TF-M
+main repository to host the examples, demonstrations, third-party modules,
+thrid-party secure partitions, etc.
+
+*******
+License
+*******
+
+The default license of new source code in this repository is :doc:`BSD-3 <license>`.
+
+Some source files are contributed by the third-parties or derived from the
+external projects. A license file should be included in the root folder of these
+source files if it has a different licence.
+
+****************
+Folder Structure
+****************
+
+- examples - This foloder hosts the examples and demos for TF-M.
+- partitions - This folder hosts the supplementary or third-party secure
+partitions for TF-M.
+
+*****************************
+Contribute to this repository
+*****************************
+
+The `contributing process <https://tf-m-user-guide.trustedfirmware.org/docs/contributing/contributing_process.html>`_ is same as TF-M main repository.
+
+*Copyright (c) 2021, Arm Limited. All rights reserved.*