DOC: update documentation.

Add documentation covering:
  - developer information about architecture
  - project structure and building
  - project overview and service descriptions
  - the portability model for supporting hardware

Signed-off-by: Julian Hall <julian.hall@arm.com>
Co-Authored-By: Gyorgy Szing <gyorgy.szing@gmail.com>
Change-Id: I8bf9c01a66350719d82a7ca2bc1c78a8ab17978d
diff --git a/docs/developer/running-tests.rst b/docs/developer/running-tests.rst
new file mode 100644
index 0000000..be0e82a
--- /dev/null
+++ b/docs/developer/running-tests.rst
@@ -0,0 +1,48 @@
+Running Tests
+=============
+
+
+
+Running component tests
+-----------------------
+On successfully completing the steps above, a binary executable called 'component-test'
+will have been created.  Because this deployment targets the linux-pc environment, the
+executable may be run as a native application.  The application uses the stock CppUtest
+command line test runner.
+
+To run component tests, use::
+
+  ./component-test -v
+
+  Typical verbose output:
+  TEST(PackedCprotocolChecks, checkTsStatusCodes) - 0 ms
+  TEST(InternalTrustedStorageTests, storeNewItem) - 0 ms
+  TEST(E2EcryptoOpTests, generateRandomNumbers) - 2 ms
+  TEST(E2EcryptoOpTests, asymEncryptDecrypt) - 4 ms
+  TEST(E2EcryptoOpTests, signAndVerifyHash) - 40 ms
+  TEST(E2EcryptoOpTests, exportAndImportKeyPair) - 18 ms
+  TEST(E2EcryptoOpTests, exportPublicKey) - 7 ms
+  TEST(E2EcryptoOpTests, generatePersistentKeys) - 39 ms
+  TEST(E2EcryptoOpTests, generateVolatileKeys) - 20 ms
+  TEST(CryptoFaultTests, randomNumbersWithBrokenStorage) - 0 ms
+  TEST(CryptoFaultTests, persistentKeysWithBrokenStorage) - 9 ms
+  TEST(CryptoFaultTests, volatileKeyWithBrokenStorage) - 8 ms
+  TEST(PocCryptoOpTests, checkOpSequence) - 13 ms
+  TEST(CryptoMsgTests, SignHashOutMsgTest) - 0 ms
+  TEST(CryptoMsgTests, SignHashInMsgTest) - 0 ms
+  TEST(CryptoMsgTests, ExportPublicKeyOutMsgTest) - 1 ms
+  TEST(CryptoMsgTests, ExportPublicKeyInMsgTest) - 0 ms
+  TEST(CryptoMsgTests, GenerateKeyInMsgTest) - 0 ms
+  TEST(ServiceFrameworkTests, serviceWithOps) - 0 ms
+  TEST(ServiceFrameworkTests, serviceWithNoOps) - 0 ms
+  TEST(TsDemoTests, runTsDemo) - 71 ms
+
+  OK (21 tests, 21 ran, 159 checks, 0 ignored, 0 filtered out, 233 ms)
+
+
+
+--------------
+
+*Copyright (c) 2020-2021, Arm Limited and Contributors. All rights reserved.*
+
+SPDX-License-Identifier: BSD-3-Clause