Docs: Clarify the build override rules
This patch adds the additional config override rules as present
in the Build system.
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
Change-Id: I5c13fcbebbef32d8b5872efffc14b64ed4d2a74d
diff --git a/docs/getting_started/tfm_build_instruction.rst b/docs/getting_started/tfm_build_instruction.rst
index 5410fad..c4a495f 100644
--- a/docs/getting_started/tfm_build_instruction.rst
+++ b/docs/getting_started/tfm_build_instruction.rst
@@ -39,14 +39,23 @@
All configuration options are provided by cmake variables, and their default
values, with docstrings, can be found in ``config/config_default.cmake``.
-Configuration is provided in multiple stages, with multiple priorities.
+Configuration is provided in multiple stages, and each subsequent stage
+can override settings of the previous stage.
1. ``config/config_default.cmake`` is loaded.
- 2. Command-line variable settings are applied, overriding all previous settings.
- 3. If it exists, CMAKE_BUILD_TYPE specific config is applied from ``config/build_type/<build_type>.cmake``, overriding all previous settings.
- 4. If it exists, TFM Profile specific config is applied from ``config/profile/<tfm_profile>.cmake``, overriding all previous settings.
- 5. Target specific config from ``platform/ext/target/<target_platform>/config.cmake`` is applied, overriding all previous settings.
- 6. If the ``TFM_EXTRA_CONFIG_PATH`` variable has been set, that file is loaded and overrides all previous settings.
+ 2. Command-line variable settings are applied.
+ 3. If it exists, CMAKE_BUILD_TYPE specific config is applied from
+ ``config/build_type/<build_type>.cmake``.
+ 4. If TEST_PSA_TEST is set, then PSA API test related config is applied from
+ ``config/tests/config_test_psa_api.cmake``.
+ 5. If it exists, TFM Profile specific config is applied from
+ ``config/profile/<tfm_profile>.cmake``.
+ 6. Target specific config from ``platform/ext/target/<target_platform>/config.cmake``
+ is applied.
+ 7. If CRYPTO_HW_ACCELERATOR is set, then a config specific to the
+ accelerator type is applied if it exists.
+ 8. If the ``TFM_EXTRA_CONFIG_PATH`` variable has been set, that file is
+ loaded.
.. Warning::
This means that command-line settings are not applied when they conflict