doc: Move content from Porting Guide
The Porting Guide document is broken down into separate,
per-topic documents that all live under the new "Porting"
chapter.
Change-Id: I269fa06cbf6544ce3c76700d1fcf3a669793c483
Signed-off-by: Paul Beesley <paul.beesley@arm.com>
Signed-off-by: Jimmy Brisson <jimmy.brisson@arm.com>
diff --git a/docs/porting/storage.rst b/docs/porting/storage.rst
new file mode 100644
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--- /dev/null
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+Storage abstraction layer
+=========================
+
+In order to improve platform independence and portability a storage abstraction
+layer is used to store test results to non-volatile platform storage.
+
+Each platform should register devices and their drivers via the Storage layer.
+These drivers then need to be initialized in ``tftf_platform_setup()`` function.
+
+It is mandatory to implement at least one storage driver. For the FVP and Juno
+platforms the NOR Flash driver is provided as the default means to store test
+results to storage. The storage layer is described in the header file
+``include/lib/io_storage.h``. The implementation of the common library is in
+``drivers/io/io_storage.c`` and the driver files are located in ``drivers/io/``.
+
+--------------
+
+*Copyright (c) 2019, Arm Limited. All rights reserved.*