arm-trusted-firmware/docs/getting_started/build-internals.rst

Internal Build Options
======================

|TF-A| internally uses certain options that are not exposed directly through
:ref:`build-options <build options>` but enabled or disabled indirectly and
depends on certain options to be enabled or disabled.

.. _build_options_internal:

-  ``CTX_INCLUDE_EL2_REGS``: This boolean option provides context save/restore
   operations when entering/exiting an EL2 execution context. This is of primary
   interest when Armv8.4-SecEL2 or RME extension is implemented.
   Default is 0 (disabled). This option will be set to 1 (enabled) when ``SPD=spmd``
   and ``SPMD_SPM_AT_SEL2`` is set or when ``ENABLE_RME`` is set to 1 (enabled).

- ``FFH_SUPPORT``: This boolean option provides support to enable Firmware First
  handling (FFH) of External aborts and SError interrupts originating from lower
  ELs which gets trapped in EL3. This option will be set to 1 (enabled) if
  ``HANDLE_EA_EL3_FIRST_NS`` is set. Currently only NS world routes EA to EL3 but
  in future when Secure/Realm wants to use FFH then they can introduce new macros
  which will enable this option implicitly.

-  ``OPTEE_SP_FW_CONFIG``: DTC build flag to include OP-TEE as SP in
   tb_fw_config device tree. This flag is defined only when
   ``ARM_SPMC_MANIFEST_DTS`` manifest file name contains pattern optee_sp.

-  ``TRUSTY_SP_FW_CONFIG``: DTC build flag to include Trusty as SP in
   tb_fw_config device tree. This flag is defined only when
   ``ARM_SPMC_MANIFEST_DTS`` manifest file name contains pattern trusty_sp.