stm32mp1: add OP-TEE support

Support booting OP-TEE as BL32 boot stage and secure runtime
service.

OP-TEE executes in internal RAM and uses a secure DDR area to store
the pager pagestore. Memory mapping and TZC are configured accordingly
prior OP-TEE boot. OP-TEE image is expected in OP-TEE v2 format where
a header file describes the effective boot images. This change
post processes header file content to get OP-TEE load addresses
and set OP-TEE boot arguments.

Change-Id: I02ef8b915e4be3e95b27029357d799d70e01cd44
Signed-off-by: Yann Gautier <yann.gautier@st.com>
Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
diff --git a/docs/plat/stm32mp1.rst b/docs/plat/stm32mp1.rst
index bfae9cc..75dfa3f 100644
--- a/docs/plat/stm32mp1.rst
+++ b/docs/plat/stm32mp1.rst
@@ -69,11 +69,15 @@
 
 ROM code -> BL2 (compiled with BL2_AT_EL3) -> BL32 (SP_min) -> BL33 (U-Boot)
 
+or if Op-TEE is used:
+
+ROM code -> BL2 (compiled with BL2_AT_EL3) -> OP-TEE -> BL33 (U-Boot)
+
 
 Build Instructions
 ------------------
 
-To build:
+To build with SP_min:
 
 .. code:: bash
 
@@ -83,6 +87,12 @@
     make DEVICE_TREE=stm32mp157c-ev1 all
     ./tools/mkimage -T stm32image -a 0xC0100000 -e 0xC0100000 -d u-boot.bin u-boot.stm32
 
+To build TF-A with with Op-TEE support:
+
+.. code:: bash
+
+    make CROSS_COMPILE=arm-linux-gnueabihf- PLAT=stm32mp1 ARCH=aarch32 ARM_ARCH_MAJOR=7 AARCH32_SP=optee
+
 The following build options are supported:
 
 - ``ENABLE_STACK_PROTECTOR``: To enable the stack protection.