ARMv7 target is driven by ARM_ARCH_MAJOR==7
External build environment shall sets directive ARM_ARCH_MAJOR to 7
to specify a target ARMv7-A core.
As ARM-TF expects AARCH to be set, ARM_ARCH_MAJOR==7 mandates
AARCH=aarch32.
The toolchain target architecture/cpu is delegated after the platform
configuration is parsed. Platform shall define target core through
ARM_CORTEX_A<x>=yes, <x> being 5, 7, 9, 12, 15 and/or 17.
Platform can bypass ARM_CORTEX_A<x>=yes directive and provide straight
the toolchain target directive through MARCH32_DIRECTIVE.
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
diff --git a/docs/firmware-design.rst b/docs/firmware-design.rst
index 7cc1970..93c13d2 100644
--- a/docs/firmware-design.rst
+++ b/docs/firmware-design.rst
@@ -2520,6 +2520,35 @@
table entries for a given stage of translation for a particular translation
regime.
+ARMv7
+~~~~~
+
+This Architecture Extension is targeted when ``ARM_ARCH_MAJOR`` == 7.
+
+There are several ARMv7 extensions available. Obviously the TrustZone
+extension is mandatory to support the ARM Trusted Firmware bootloader
+and runtime services.
+
+Platform implementing an ARMv7 system can to define from its target
+Cortex-A architecture through ``ARM_CORTEX_A<X> = yes`` in their
+``plaform.mk`` script. For example ``ARM_CORTEX_A15=yes`` for a
+Cortex-A15 target.
+
+Platform can also set ``ARM_WITH_NEON=yes`` to enable neon support.
+Note that using neon at runtime has constraints on non secure wolrd context.
+The trusted firmware does not yet provide VFP context management.
+
+Directive ``ARM_CORTEX_A<x>`` and ``ARM_WITH_NEON`` are used to set
+the toolchain target architecture directive.
+
+Platform may choose to not define straight the toolchain target architecture
+directive by defining ``MARCH32_DIRECTIVE``.
+I.e:
+
+::
+
+ MARCH32_DIRECTIVE := -mach=armv7-a
+
Code Structure
--------------