Platform: RSS: Improve ATU mapping
Makes the following improvements to the way ATU regions are mapped in
RSS:
- Map UART at the end of the ATU window using the highest region
number to minimise its impact on other regions, since it is only
present for debug purposes.
- Open the host boot image regions only for the period that each image
is being loaded. Also means the same region number can be reused,
but unfortunately not the logical address since MCUBoot will not
permit multiple images with the same load address.
- Move host addresses to host_base_address.h so that they can easily
be replaced for different RSS integrations.
Change-Id: I5f99128d10baae6fb525bb4f7c2ef5c93a342594
Signed-off-by: Jamie Fox <jamie.fox@arm.com>
diff --git a/docs/platform/arm/rss/readme.rst b/docs/platform/arm/rss/readme.rst
index abc2d2f..c676598 100644
--- a/docs/platform/arm/rss/readme.rst
+++ b/docs/platform/arm/rss/readme.rst
@@ -56,9 +56,13 @@
<binary infile> \
<signed binary outfile>
-The ``load address`` is the address to which BL2 will load the image. The RSS
-ATU should be configured to map this logical address to the physical address in
-the host system that the image needs to be loaded to.
+The ``load address`` is the logical address in the RSS memory map to which BL2
+will load the image. RSS FW expects the first host image to be loaded to address
+``0x70000000`` (the beginning of the RSS ATU host access region), and each
+subsequent host image to be loaded at an offset of ``0x100000`` from the
+previous image. The RSS ATU should be configured to map these logical addresses
+to the physical addresses in the host system that the images need to be loaded
+to.
For more information on the ``imgtool`` parameters, see the MCUBoot
`imgtool documentation <https://docs.mcuboot.com/imgtool.html>`_.