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+######################################
+Adding partitions for regression tests
+######################################
+
+************
+Introduction
+************
+
+Some test group may need specific test services. These test services may support
+one or more groups thus developers shall determine the proper test scope.
+Currently, TF-M test services are located under ``tf-m-tests/test/secure_fw``.
+
++---------------------------------------+---------------------------------------------------------------+
+| Folder name                           | Description                                                   |
++=======================================+===============================================================+
+| test/secure_fw/suites/<suite>/service | Test service divided into corresponding suite subdirectories. |
++---------------------------------------+---------------------------------------------------------------+
+| test/secure_fw/common_test_services   | Common test services.                                         |
++---------------------------------------+---------------------------------------------------------------+
+
+**************
+Implementation
+**************
+
+Adding a test partiton to provide test services is same as adding a secure
+partition, generally the process can be referenced from the document
+`Adding Secure Partition <https://tf-m-user-guide.trustedfirmware.org/integration_guide/services/tfm_secure_partition_addition.html>`_.
+
+Test Partition Specific Manifest Attributes
+===========================================
+
+Each test service must have resource requirements declared in a manifest file,
+the contents of test services are the same as secure partitions, but their
+locations are different. Test service manifests shall be set in
+``tf-m-tests/test/secure_fw/tfm_test_manifest_list.yaml``.
+
+There are some test purpose attributes in Secure Partition manifests that are
+**NOT** compatible with FF-M.
+They should be used in Test Partitions only.
+
+weak_dependencies
+-----------------
+A TF-M regression test Partition calls other RoT services for test. But it
+can still run other tests if some of the RoT services are disabled.
+TF-M defines a ``"weak_dependencies"`` attribute in partition manifests of
+regression test partitions to describe test service access to other RoT
+services. It *shall* be only used for TF-M regression test services.
+
+model
+-----
+A TF-M regression test Partition may support both the SFN and IPC model.
+The actual model being used follows the SPM backend enabled.
+
+The TF-M build system supports this by allowing Secure Partitions to set
+the ``model`` attribute to ``dual``.
+The manifest tool will then change it to the corresponding value according
+to the current backend selected.
+
+The Test Partitions use the following definitions to know what model is being
+built:
+
+- ``<<partition_name>>_MODEL_IPC``, ``1`` if IPC model is used.
+- ``<<partition_name>>_MODEL_SFN``, ``1`` if SFN model is used.
+
+Test service implementation
+===========================
+
+Test service of individual test
+-------------------------------
+
+An individual test dedicated test service should be put under the corresponding
+test folder ``test/secure_fw/suites/<test_name>``.
+
+``add_subdirectory(suites/<test_name>/<service_dir>)`` shall be added into
+``tf-m-tests/test/secure_fw/secure_tests.cmake`` to make sure that the test
+service is built with secure side configuration.
+
+Common test service
+-------------------
+
+If a new test service is required by multiple test suites, the code should be
+put under ``test/secure_fw/common_test_services``. If the new test suite relies
+on a common test service, please make sure that the build implementation of the
+test service is linked correctly, including the header files and libraries.
+
+--------------
+
+*Copyright (c) 2022, Arm Limited. All rights reserved.*