Docs: Add note about erasing storage before testing
Adds a note to the user guide about erasing the storage area before
running tests on Musca boards.
Change-Id: Ib52e494d2822386ff6300425e8f82a2a896a417e
Signed-off-by: Jamie Fox <jamie.fox@arm.com>
diff --git a/docs/getting_started/tfm_user_guide.rst b/docs/getting_started/tfm_user_guide.rst
index c9430bd..f193ec6 100644
--- a/docs/getting_started/tfm_user_guide.rst
+++ b/docs/getting_started/tfm_user_guide.rst
@@ -274,6 +274,22 @@
Regression tests with BL2 bootloader
====================================
+.. note::
+
+ As the Internal Trusted Storage and Protected Storage tests use persistent
+ storage, it is recommended to erase the storage area before running the
+ tests. Existing data may prevent the tests from running to completion if,
+ for example, there is not enough free space for the test data or the UIDs
+ used by the tests have already been created with the write-once flag set.
+ Repeated test runs can be done without erasing between runs.
+
+ To erase the storage when flashing an image, ``-fill 0xFF <start_addr>
+ <end_addr>`` can be added to the ``srec_cat`` command used to create the
+ combined hex file. The ``<start_addr>`` and ``<end_addr>`` are the start and
+ end addresses of the storage area, found in the board's ``flash_layout.h``
+ file. The board's flash can also be erased via a debugger; see your IDE's
+ documentation for instructions.
+
After completing the procedure you should see the following messages on the
DAPLink UART (baud 115200 8n1)::