Build Options
=============
The TF-A build system supports the following build options. Unless mentioned
otherwise, these options are expected to be specified at the build command
line and are not to be modified in any component makefiles. Note that the
build system doesn't track dependency for build options. Therefore, if any of
the build options are changed from a previous build, a clean build must be
performed.
.. _build_options_common:
Common build options
--------------------
- ``AARCH32_INSTRUCTION_SET``: Choose the AArch32 instruction set that the
compiler should use. Valid values are T32 and A32. It defaults to T32 due to
code having a smaller resulting size.
- ``AARCH32_SP`` : Choose the AArch32 Secure Payload component to be built as
as the BL32 image when ``ARCH=aarch32``. The value should be the path to the
directory containing the SP source, relative to the ``bl32/``; the directory
is expected to contain a makefile called ``<aarch32_sp-value>.mk``.
- ``ARCH`` : Choose the target build architecture for TF-A. It can take either
``aarch64`` or ``aarch32`` as values. By default, it is defined to
``aarch64``.
- ``ARM_ARCH_MAJOR``: The major version of Arm Architecture to target when
compiling TF-A. Its value must be numeric, and defaults to 8 . See also,
*Armv8 Architecture Extensions* and *Armv7 Architecture Extensions* in
:ref:`Firmware Design`.
- ``ARM_ARCH_MINOR``: The minor version of Arm Architecture to target when
compiling TF-A. Its value must be a numeric, and defaults to 0. See also,
*Armv8 Architecture Extensions* in :ref:`Firmware Design`.
- ``BL2``: This is an optional build option which specifies the path to BL2
image for the ``fip`` target. In this case, the BL2 in the TF-A will not be
built.
- ``BL2U``: This is an optional build option which specifies the path to
BL2U image. In this case, the BL2U in TF-A will not be built.
- ``BL2_AT_EL3``: This is an optional build option that enables the use of
BL2 at EL3 execution level.
- ``BL2_IN_XIP_MEM``: In some use-cases BL2 will be stored in eXecute In Place
(XIP) memory, like BL1. In these use-cases, it is necessary to initialize
the RW sections in RAM, while leaving the RO sections in place. This option
enable this use-case. For now, this option is only supported when BL2_AT_EL3
is set to '1'.
- ``BL31``: This is an optional build option which specifies the path to
BL31 image for the ``fip`` target. In this case, the BL31 in TF-A will not
be built.
- ``BL31_KEY``: This option is used when ``GENERATE_COT=1``. It specifies the
file that contains the BL31 private key in PEM format. If ``SAVE_KEYS=1``,
this file name will be used to save the key.
- ``BL32``: This is an optional build option which specifies the path to
BL32 image for the ``fip`` target. In this case, the BL32 in TF-A will not
be built.
- ``BL32_EXTRA1``: This is an optional build option which specifies the path to
Trusted OS Extra1 image for the ``fip`` target.
- ``BL32_EXTRA2``: This is an optional build option which specifies the path to
Trusted OS Extra2 image for the ``fip`` target.
- ``BL32_KEY``: This option is used when ``GENERATE_COT=1``. It specifies the
file that contains the BL32 private key in PEM format. If ``SAVE_KEYS=1``,
this file name will be used to save the key.
- ``BL33``: Path to BL33 image in the host file system. This is mandatory for
``fip`` target in case TF-A BL2 is used.
- ``BL33_KEY``: This option is used when ``GENERATE_COT=1``. It specifies the
file that contains the BL33 private key in PEM format. If ``SAVE_KEYS=1``,
this file name will be used to save the key.
- ``BRANCH_PROTECTION``: Numeric value to enable ARMv8.3 Pointer Authentication
and ARMv8.5 Branch Target Identification support for TF-A BL images themselves.
If enabled, it is needed to use a compiler that supports the option
``-mbranch-protection``. Selects the branch protection features to use:
- 0: Default value turns off all types of branch protection
- 1: Enables all types of branch protection features
- 2: Return address signing to its standard level
- 3: Extend the signing to include leaf functions
The table below summarizes ``BRANCH_PROTECTION`` values, GCC compilation options
and resulting PAuth/BTI features.
+-------+--------------+-------+-----+
| Value | GCC option | PAuth | BTI |
+=======+==============+=======+=====+
| 0 | none | N | N |
+-------+--------------+-------+-----+
| 1 | standard | Y | Y |
+-------+--------------+-------+-----+
| 2 | pac-ret | Y | N |
+-------+--------------+-------+-----+
| 3 | pac-ret+leaf | Y | N |
+-------+--------------+-------+-----+
This option defaults to 0 and this is an experimental feature.
Note that Pointer Authentication is enabled for Non-secure world
irrespective of the value of this option if the CPU supports it.
- ``BUILD_MESSAGE_TIMESTAMP``: String used to identify the time and date of the
compilation of each build. It must be set to a C string (including quotes
where applicable). Defaults to a string that contains the time and date of
the compilation.
- ``BUILD_STRING``: Input string for VERSION_STRING, which allows the TF-A
build to be uniquely identified. Defaults to the current git commit id.
- ``CFLAGS``: Extra user options appended on the compiler's command line in
addition to the options set by the build system.
- ``COLD_BOOT_SINGLE_CPU``: This option indicates whether the platform may
release several CPUs out of reset. It can take either 0 (several CPUs may be
brought up) or 1 (only one CPU will ever be brought up during cold reset).
Default is 0. If the platform always brings up a single CPU, there is no
need to distinguish between primary and secondary CPUs and the boot path can
be optimised. The ``plat_is_my_cpu_primary()`` and
``plat_secondary_cold_boot_setup()`` platform porting interfaces do not need
to be implemented in this case.
- ``COT``: When Trusted Boot is enabled, selects the desired chain of trust.
Defaults to ``tbbr``.
- ``CRASH_REPORTING``: A non-zero value enables a console dump of processor
register state when an unexpected exception occurs during execution of
BL31. This option defaults to the value of ``DEBUG`` - i.e. by default
this is only enabled for a debug build of the firmware.
- ``CREATE_KEYS``: This option is used when ``GENERATE_COT=1``. It tells the
certificate generation tool to create new keys in case no valid keys are
present or specified. Allowed options are '0' or '1'. Default is '1'.
- ``CTX_INCLUDE_AARCH32_REGS`` : Boolean option that, when set to 1, will cause
the AArch32 system registers to be included when saving and restoring the
CPU context. The option must be set to 0 for AArch64-only platforms (that
is on hardware that does not implement AArch32, or at least not at EL1 and
higher ELs). Default value is 1.
- ``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 extension is implemented. Default is 0 (disabled).
This option must be equal to 1 (enabled) when ``SPD=spmd`` and
``SPMD_SPM_AT_SEL2`` is set.
- ``CTX_INCLUDE_FPREGS``: Boolean option that, when set to 1, will cause the FP
registers to be included when saving and restoring the CPU context. Default
is 0.
- ``CTX_INCLUDE_PAUTH_REGS``: Boolean option that, when set to 1, enables
Pointer Authentication for Secure world. This will cause the ARMv8.3-PAuth
registers to be included when saving and restoring the CPU context as
part of world switch. Default value is 0 and this is an experimental feature.
Note that Pointer Authentication is enabled for Non-secure world irrespective
of the value of this flag if the CPU supports it.
- ``DEBUG``: Chooses between a debug and release build. It can take either 0
(release) or 1 (debug) as values. 0 is the default.
- ``DECRYPTION_SUPPORT``: This build flag enables the user to select the
authenticated decryption algorithm to be used to decrypt firmware/s during
boot. It accepts 2 values: ``aes_gcm`` and ``none``. The default value of
this flag is ``none`` to disable firmware decryption which is an optional
feature as per TBBR. Also, it is an experimental feature.
- ``DISABLE_BIN_GENERATION``: Boolean option to disable the generation
of the binary image. If set to 1, then only the ELF image is built.
0 is the default.
- ``DYN_DISABLE_AUTH``: Provides the capability to dynamically disable Trusted
Board Boot authentication at runtime. This option is meant to be enabled only
for development platforms. ``TRUSTED_BOARD_BOOT`` flag must be set if this
flag has to be enabled. 0 is the default.
- ``E``: Boolean option to make warnings into errors. Default is 1.
- ``EL3_PAYLOAD_BASE``: This option enables booting an EL3 payload instead of
the normal boot flow. It must specify the entry point address of the EL3
payload. Please refer to the "Booting an EL3 payload" section for more
details.
- ``ENABLE_AMU``: Boolean option to enable Activity Monitor Unit extensions.
This is an optional architectural feature available on v8.4 onwards. Some
v8.2 implementations also implement an AMU and this option can be used to
enable this feature on those systems as well. Default is 0.
- ``ENABLE_ASSERTIONS``: This option controls whether or not calls to ``assert()``
are compiled out. For debug builds, this option defaults to 1, and calls to
``assert()`` are left in place. For release builds, this option defaults to 0
and calls to ``assert()`` function are compiled out. This option can be set
independently of ``DEBUG``. It can also be used to hide any auxiliary code
that is only required for the assertion and does not fit in the assertion
itself.
- ``ENABLE_BACKTRACE``: This option controls whether to enable backtrace
dumps or not. It is supported in both AArch64 and AArch32. However, in
AArch32 the format of the frame records are not defined in the AAPCS and they
are defined by the implementation. This implementation of backtrace only
supports the format used by GCC when T32 interworking is disabled. For this
reason enabling this option in AArch32 will force the compiler to only
generate A32 code. This option is enabled by default only in AArch64 debug
builds, but this behaviour can be overridden in each platform's Makefile or
in the build command line.
- ``ENABLE_LTO``: Boolean option to enable Link Time Optimization (LTO)
support in GCC for TF-A. This option is currently only supported for
AArch64. Default is 0.
- ``ENABLE_MPAM_FOR_LOWER_ELS``: Boolean option to enable lower ELs to use MPAM
feature. MPAM is an optional Armv8.4 extension that enables various memory
system components and resources to define partitions; software running at
various ELs can assign themselves to desired partition to control their
performance aspects.
When this option is set to ``1``, EL3 allows lower ELs to access their own
MPAM registers without trapping into EL3. This option doesn't make use of
partitioning in EL3, however. Platform initialisation code should configure
and use partitions in EL3 as required. This option defaults to ``0``.
- ``ENABLE_PIE``: Boolean option to enable Position Independent Executable(PIE)
support within generic code in TF-A. This option is currently only supported
in BL2_AT_EL3, BL31, and BL32 (TSP). Default is 0.
- ``ENABLE_PMF``: Boolean option to enable support for optional Performance
Measurement Framework(PMF). Default is 0.
- ``ENABLE_PSCI_STAT``: Boolean option to enable support for optional PSCI
functions ``PSCI_STAT_RESIDENCY`` and ``PSCI_STAT_COUNT``. Default is 0.
In the absence of an alternate stat collection backend, ``ENABLE_PMF`` must
be enabled. If ``ENABLE_PMF`` is set, the residency statistics are tracked in
software.
- ``ENABLE_RUNTIME_INSTRUMENTATION``: Boolean option to enable runtime
instrumentation which injects timestamp collection points into TF-A to
allow runtime performance to be measured. Currently, only PSCI is
instrumented. Enabling this option enables the ``ENABLE_PMF`` build option
as well. Default is 0.
- ``ENABLE_SPE_FOR_LOWER_ELS`` : Boolean option to enable Statistical Profiling
extensions. This is an optional architectural feature for AArch64.
The default is 1 but is automatically disabled when the target architecture
is AArch32.
- ``ENABLE_SVE_FOR_NS``: Boolean option to enable Scalable Vector Extension
(SVE) for the Non-secure world only. SVE is an optional architectural feature
for AArch64. Note that when SVE is enabled for the Non-secure world, access
to SIMD and floating-point functionality from the Secure world is disabled.
This is to avoid corruption of the Non-secure world data in the Z-registers
which are aliased by the SIMD and FP registers. The build option is not
compatible with the ``CTX_INCLUDE_FPREGS`` build option, and will raise an
assert on platforms where SVE is implemented and ``ENABLE_SVE_FOR_NS`` set to
1. The default is 1 but is automatically disabled when the target
architecture is AArch32.
- ``ENABLE_STACK_PROTECTOR``: String option to enable the stack protection
checks in GCC. Allowed values are "all", "strong", "default" and "none". The
default value is set to "none". "strong" is the recommended stack protection
level if this feature is desired. "none" disables the stack protection. For
all values other than "none", the ``plat_get_stack_protector_canary()``
platform hook needs to be implemented. The value is passed as the last
component of the option ``-fstack-protector-$ENABLE_STACK_PROTECTOR``.
- ``ENCRYPT_BL31``: Binary flag to enable encryption of BL31 firmware. This
flag depends on ``DECRYPTION_SUPPORT`` build flag which is marked as
experimental.
- ``ENCRYPT_BL32``: Binary flag to enable encryption of Secure BL32 payload.
This flag depends on ``DECRYPTION_SUPPORT`` build flag which is marked as
experimental.
- ``ENC_KEY``: A 32-byte (256-bit) symmetric key in hex string format. It could
either be SSK or BSSK depending on ``FW_ENC_STATUS`` flag. This value depends
on ``DECRYPTION_SUPPORT`` build flag which is marked as experimental.
- ``ENC_NONCE``: A 12-byte (96-bit) encryption nonce or Initialization Vector
(IV) in hex string format. This value depends on ``DECRYPTION_SUPPORT``
build flag which is marked as experimental.
- ``ERROR_DEPRECATED``: This option decides whether to treat the usage of
deprecated platform APIs, helper functions or drivers within Trusted
Firmware as error. It can take the value 1 (flag the use of deprecated
APIs as error) or 0. The default is 0.
- ``EL3_EXCEPTION_HANDLING``: When set to ``1``, enable handling of exceptions
targeted at EL3. When set ``0`` (default), no exceptions are expected or
handled at EL3, and a panic will result. This is supported only for AArch64
builds.
- ``FAULT_INJECTION_SUPPORT``: ARMv8.4 extensions introduced support for fault
injection from lower ELs, and this build option enables lower ELs to use
Error Records accessed via System Registers to inject faults. This is
applicable only to AArch64 builds.
This feature is intended for testing purposes only, and is advisable to keep
disabled for production images.
- ``FIP_NAME``: This is an optional build option which specifies the FIP
filename for the ``fip`` target. Default is ``fip.bin``.
- ``FWU_FIP_NAME``: This is an optional build option which specifies the FWU
FIP filename for the ``fwu_fip`` target. Default is ``fwu_fip.bin``.
- ``FW_ENC_STATUS``: Top level firmware's encryption numeric flag, values:
::
0: Encryption is done with Secret Symmetric Key (SSK) which is common
for a class of devices.
1: Encryption is done with Binding Secret Symmetric Key (BSSK) which is
unique per device.
This flag depends on ``DECRYPTION_SUPPORT`` build flag which is marked as
experimental.
- ``GENERATE_COT``: Boolean flag used to build and execute the ``cert_create``
tool to create certificates as per the Chain of Trust described in
:ref:`Trusted Board Boot`. The build system then calls ``fiptool`` to
include the certificates in the FIP and FWU_FIP. Default value is '0'.
Specify both ``TRUSTED_BOARD_BOOT=1`` and ``GENERATE_COT=1`` to include support
for the Trusted Board Boot feature in the BL1 and BL2 images, to generate
the corresponding certificates, and to include those certificates in the
FIP and FWU_FIP.
Note that if ``TRUSTED_BOARD_BOOT=0`` and ``GENERATE_COT=1``, the BL1 and BL2
images will not include support for Trusted Board Boot. The FIP will still
include the corresponding certificates. This FIP can be used to verify the
Chain of Trust on the host machine through other mechanisms.
Note that if ``TRUSTED_BOARD_BOOT=1`` and ``GENERATE_COT=0``, the BL1 and BL2
images will include support for Trusted Board Boot, but the FIP and FWU_FIP
will not include the corresponding certificates, causing a boot failure.
- ``GICV2_G0_FOR_EL3``: Unlike GICv3, the GICv2 architecture doesn't have
inherent support for specific EL3 type interrupts. Setting this build option
to ``1`` assumes GICv2 *Group 0* interrupts are expected to target EL3, both
by `platform abstraction layer`__ and `Interrupt Management Framework`__.
This allows GICv2 platforms to enable features requiring EL3 interrupt type.
This also means that all GICv2 Group 0 interrupts are delivered to EL3, and
the Secure Payload interrupts needs to be synchronously handed over to Secure
EL1 for handling. The default value of this option is ``0``, which means the
Group 0 interrupts are assumed to be handled by Secure EL1.
.. __: platform-interrupt-controller-API.rst
.. __: interrupt-framework-design.rst
- ``HANDLE_EA_EL3_FIRST``: When set to ``1``, External Aborts and SError
Interrupts will be always trapped in EL3 i.e. in BL31 at runtime. When set to
``0`` (default), these exceptions will be trapped in the current exception
level (or in EL1 if the current exception level is EL0).
- ``HW_ASSISTED_COHERENCY``: On most Arm systems to-date, platform-specific
software operations are required for CPUs to enter and exit coherency.
However, newer systems exist where CPUs' entry to and exit from coherency
is managed in hardware. Such systems require software to only initiate these
operations, and the rest is managed in hardware, minimizing active software
management. In such systems, this boolean option enables TF-A to carry out
build and run-time optimizations during boot and power management operations.
This option defaults to 0 and if it is enabled, then it implies
``WARMBOOT_ENABLE_DCACHE_EARLY`` is also enabled.
If this flag is disabled while the platform which TF-A is compiled for
includes cores that manage coherency in hardware, then a compilation error is
generated. This is based on the fact that a system cannot have, at the same
time, cores that manage coherency in hardware and cores that don't. In other
words, a platform cannot have, at the same time, cores that require
``HW_ASSISTED_COHERENCY=1`` and cores that require
``HW_ASSISTED_COHERENCY=0``.
Note that, when ``HW_ASSISTED_COHERENCY`` is enabled, version 2 of
translation library (xlat tables v2) must be used; version 1 of translation
library is not supported.
- ``INVERTED_MEMMAP``: memmap tool print by default lower addresses at the
bottom, higher addresses at the top. This buid flag can be set to '1' to
invert this behavior. Lower addresses will be printed at the top and higher
addresses at the bottom.
- ``JUNO_AARCH32_EL3_RUNTIME``: This build flag enables you to execute EL3
runtime software in AArch32 mode, which is required to run AArch32 on Juno.
By default this flag is set to '0'. Enabling this flag builds BL1 and BL2 in
AArch64 and facilitates the loading of ``SP_MIN`` and BL33 as AArch32 executable
images.
- ``KEY_ALG``: This build flag enables the user to select the algorithm to be
used for generating the PKCS keys and subsequent signing of the certificate.
It accepts 3 values: ``rsa``, ``rsa_1_5`` and ``ecdsa``. The option
``rsa_1_5`` is the legacy PKCS#1 RSA 1.5 algorithm which is not TBBR
compliant and is retained only for compatibility. The default value of this
flag is ``rsa`` which is the TBBR compliant PKCS#1 RSA 2.1 scheme.
- ``KEY_SIZE``: This build flag enables the user to select the key size for
the algorithm specified by ``KEY_ALG``. The valid values for ``KEY_SIZE``
depend on the chosen algorithm and the cryptographic module.
+-----------+------------------------------------+
| KEY_ALG | Possible key sizes |
+===========+====================================+
| rsa | 1024 , 2048 (default), 3072, 4096* |
+-----------+------------------------------------+
| ecdsa | unavailable |
+-----------+------------------------------------+
* Only 2048 bits size is available with CryptoCell 712 SBROM release 1.
Only 3072 bits size is available with CryptoCell 712 SBROM release 2.
- ``HASH_ALG``: This build flag enables the user to select the secure hash
algorithm. It accepts 3 values: ``sha256``, ``sha384`` and ``sha512``.
The default value of this flag is ``sha256``.
- ``LDFLAGS``: Extra user options appended to the linkers' command line in
addition to the one set by the build system.
- ``LOG_LEVEL``: Chooses the log level, which controls the amount of console log
output compiled into the build. This should be one of the following:
::
0 (LOG_LEVEL_NONE)
10 (LOG_LEVEL_ERROR)
20 (LOG_LEVEL_NOTICE)
30 (LOG_LEVEL_WARNING)
40 (LOG_LEVEL_INFO)
50 (LOG_LEVEL_VERBOSE)
All log output up to and including the selected log level is compiled into
the build. The default value is 40 in debug builds and 20 in release builds.
- ``MEASURED_BOOT``: Boolean flag to include support for the Measured Boot
feature. If this flag is enabled ``TRUSTED_BOARD_BOOT`` must be set.
This option defaults to 0 and is an experimental feature in the stage of
development.
- ``NON_TRUSTED_WORLD_KEY``: This option is used when ``GENERATE_COT=1``. It
specifies the file that contains the Non-Trusted World private key in PEM
format. If ``SAVE_KEYS=1``, this file name will be used to save the key.
- ``NS_BL2U``: Path to NS_BL2U image in the host file system. This image is
optional. It is only needed if the platform makefile specifies that it
is required in order to build the ``fwu_fip`` target.
- ``NS_TIMER_SWITCH``: Enable save and restore for non-secure timer register
contents upon world switch. It can take either 0 (don't save and restore) or
1 (do save and restore). 0 is the default. An SPD may set this to 1 if it
wants the timer registers to be saved and restored.
- ``OVERRIDE_LIBC``: This option allows platforms to override the default libc
for the BL image. It can be either 0 (include) or 1 (remove). The default
value is 0.
- ``PL011_GENERIC_UART``: Boolean option to indicate the PL011 driver that
the underlying hardware is not a full PL011 UART but a minimally compliant
generic UART, which is a subset of the PL011. The driver will not access
any register that is not part of the SBSA generic UART specification.
Default value is 0 (a full PL011 compliant UART is present).
- ``PLAT``: Choose a platform to build TF-A for. The chosen platform name
must be subdirectory of any depth under ``plat/``, and must contain a
platform makefile named ``platform.mk``. For example, to build TF-A for the
Arm Juno board, select PLAT=juno.
- ``PRELOADED_BL33_BASE``: This option enables booting a preloaded BL33 image
instead of the normal boot flow. When defined, it must specify the entry
point address for the preloaded BL33 image. This option is incompatible with
``EL3_PAYLOAD_BASE``. If both are defined, ``EL3_PAYLOAD_BASE`` has priority
over ``PRELOADED_BL33_BASE``.
- ``PROGRAMMABLE_RESET_ADDRESS``: This option indicates whether the reset
vector address can be programmed or is fixed on the platform. It can take
either 0 (fixed) or 1 (programmable). Default is 0. If the platform has a
programmable reset address, it is expected that a CPU will start executing
code directly at the right address, both on a cold and warm reset. In this
case, there is no need to identify the entrypoint on boot and the boot path
can be optimised. The ``plat_get_my_entrypoint()`` platform porting interface
does not need to be implemented in this case.
- ``PSCI_EXTENDED_STATE_ID``: As per PSCI1.0 Specification, there are 2 formats
possible for the PSCI power-state parameter: original and extended State-ID
formats. This flag if set to 1, configures the generic PSCI layer to use the
extended format. The default value of this flag is 0, which means by default
the original power-state format is used by the PSCI implementation. This flag
should be specified by the platform makefile and it governs the return value
of PSCI_FEATURES API for CPU_SUSPEND smc function id. When this option is
enabled on Arm platforms, the option ``ARM_RECOM_STATE_ID_ENC`` needs to be
set to 1 as well.
- ``RAS_EXTENSION``: When set to ``1``, enable Armv8.2 RAS features. RAS features
are an optional extension for pre-Armv8.2 CPUs, but are mandatory for Armv8.2
or later CPUs.
When ``RAS_EXTENSION`` is set to ``1``, ``HANDLE_EA_EL3_FIRST`` must also be
set to ``1``.
This option is disabled by default.
- ``RESET_TO_BL31``: Enable BL31 entrypoint as the CPU reset vector instead
of the BL1 entrypoint. It can take the value 0 (CPU reset to BL1
entrypoint) or 1 (CPU reset to BL31 entrypoint).
The default value is 0.
- ``RESET_TO_SP_MIN``: SP_MIN is the minimal AArch32 Secure Payload provided
in TF-A. This flag configures SP_MIN entrypoint as the CPU reset vector
instead of the BL1 entrypoint. It can take the value 0 (CPU reset to BL1
entrypoint) or 1 (CPU reset to SP_MIN entrypoint). The default value is 0.
- ``ROT_KEY``: This option is used when ``GENERATE_COT=1``. It specifies the
file that contains the ROT private key in PEM format and enforces public key
hash generation. If ``SAVE_KEYS=1``, this
file name will be used to save the key.
- ``SAVE_KEYS``: This option is used when ``GENERATE_COT=1``. It tells the
certificate generation tool to save the keys used to establish the Chain of
Trust. Allowed options are '0' or '1'. Default is '0' (do not save).
- ``SCP_BL2``: Path to SCP_BL2 image in the host file system. This image is optional.
If a SCP_BL2 image is present then this option must be passed for the ``fip``
target.
- ``SCP_BL2_KEY``: This option is used when ``GENERATE_COT=1``. It specifies the
file that contains the SCP_BL2 private key in PEM format. If ``SAVE_KEYS=1``,
this file name will be used to save the key.
- ``SCP_BL2U``: Path to SCP_BL2U image in the host file system. This image is
optional. It is only needed if the platform makefile specifies that it
is required in order to build the ``fwu_fip`` target.
- ``SDEI_SUPPORT``: Setting this to ``1`` enables support for Software
Delegated Exception Interface to BL31 image. This defaults to ``0``.
When set to ``1``, the build option ``EL3_EXCEPTION_HANDLING`` must also be
set to ``1``.
- ``SEPARATE_CODE_AND_RODATA``: Whether code and read-only data should be
isolated on separate memory pages. This is a trade-off between security and
memory usage. See "Isolating code and read-only data on separate memory
pages" section in :ref:`Firmware Design`. This flag is disabled by default
and affects all BL images.
- ``SEPARATE_NOBITS_REGION``: Setting this option to ``1`` allows the NOBITS
sections of BL31 (.bss, stacks, page tables, and coherent memory) to be
allocated in RAM discontiguous from the loaded firmware image. When set, the
platform is expected to provide definitons for ``BL31_NOBITS_BASE`` and
``BL31_NOBITS_LIMIT``. When the option is ``0`` (the default), NOBITS
sections are placed in RAM immediately following the loaded firmware image.
- ``SPD``: Choose a Secure Payload Dispatcher component to be built into TF-A.
This build option is only valid if ``ARCH=aarch64``. The value should be
the path to the directory containing the SPD source, relative to
``services/spd/``; the directory is expected to contain a makefile called
``<spd-value>.mk``. The SPM Dispatcher standard service is located in
services/std_svc/spmd and enabled by ``SPD=spmd``. The SPM Dispatcher
cannot be enabled when the ``SPM_MM`` option is enabled.
- ``SPIN_ON_BL1_EXIT``: This option introduces an infinite loop in BL1. It can
take either 0 (no loop) or 1 (add a loop). 0 is the default. This loop stops
execution in BL1 just before handing over to BL31. At this point, all
firmware images have been loaded in memory, and the MMU and caches are
turned off. Refer to the "Debugging options" section for more details.
- ``SPMD_SPM_AT_SEL2`` : this boolean option is used jointly with the SPM
Dispatcher option (``SPD=spmd``). When enabled (1) it indicates the SPMC
component runs at the S-EL2 execution state provided by the Armv8.4-SecEL2
extension. This is the default when enabling the SPM Dispatcher. When
disabled (0) it indicates the SPMC component runs at the S-EL1 execution
state. This latter configuration supports pre-Armv8.4 platforms (aka not
implementing the Armv8.4-SecEL2 extension).
- ``SPM_MM`` : Boolean option to enable the Management Mode (MM)-based Secure
Partition Manager (SPM) implementation. The default value is ``0``
(disabled). This option cannot be enabled (``1``) when SPM Dispatcher is
enabled (``SPD=spmd``).
- ``SP_LAYOUT_FILE``: Platform provided path to JSON file containing the
description of secure partitions. The build system will parse this file and
package all secure partition blobs into the FIP. This file is not
necessarily part of TF-A tree. Only available when ``SPD=spmd``.
- ``SP_MIN_WITH_SECURE_FIQ``: Boolean flag to indicate the SP_MIN handles
secure interrupts (caught through the FIQ line). Platforms can enable
this directive if they need to handle such interruption. When enabled,
the FIQ are handled in monitor mode and non secure world is not allowed
to mask these events. Platforms that enable FIQ handling in SP_MIN shall
implement the api ``sp_min_plat_fiq_handler()``. The default value is 0.
- ``TRUSTED_BOARD_BOOT``: Boolean flag to include support for the Trusted Board
Boot feature. When set to '1', BL1 and BL2 images include support to load
and verify the certificates and images in a FIP, and BL1 includes support
for the Firmware Update. The default value is '0'. Generation and inclusion
of certificates in the FIP and FWU_FIP depends upon the value of the
``GENERATE_COT`` option.
.. warning::
This option depends on ``CREATE_KEYS`` to be enabled. If the keys
already exist in disk, they will be overwritten without further notice.
- ``TRUSTED_WORLD_KEY``: This option is used when ``GENERATE_COT=1``. It
specifies the file that contains the Trusted World private key in PEM
format. If ``SAVE_KEYS=1``, this file name will be used to save the key.
- ``TSP_INIT_ASYNC``: Choose BL32 initialization method as asynchronous or
synchronous, (see "Initializing a BL32 Image" section in
:ref:`Firmware Design`). It can take the value 0 (BL32 is initialized using
synchronous method) or 1 (BL32 is initialized using asynchronous method).
Default is 0.
- ``TSP_NS_INTR_ASYNC_PREEMPT``: A non zero value enables the interrupt
routing model which routes non-secure interrupts asynchronously from TSP
to EL3 causing immediate preemption of TSP. The EL3 is responsible
for saving and restoring the TSP context in this routing model. The
default routing model (when the value is 0) is to route non-secure
interrupts to TSP allowing it to save its context and hand over
synchronously to EL3 via an SMC.
.. note::
When ``EL3_EXCEPTION_HANDLING`` is ``1``, ``TSP_NS_INTR_ASYNC_PREEMPT``
must also be set to ``1``.
- ``USE_ARM_LINK``: This flag determines whether to enable support for ARM
linker. When the ``LINKER`` build variable points to the armlink linker,
this flag is enabled automatically. To enable support for armlink, platforms
will have to provide a scatter file for the BL image. Currently, Tegra
platforms use the armlink support to compile BL3-1 images.
- ``USE_COHERENT_MEM``: This flag determines whether to include the coherent
memory region in the BL memory map or not (see "Use of Coherent memory in
TF-A" section in :ref:`Firmware Design`). It can take the value 1
(Coherent memory region is included) or 0 (Coherent memory region is
excluded). Default is 1.
- ``USE_DEBUGFS``: When set to 1 this option activates an EXPERIMENTAL feature
exposing a virtual filesystem interface through BL31 as a SiP SMC function.
Default is 0.
- ``ARM_IO_IN_DTB``: This flag determines whether to use IO based on the
firmware configuration framework. This will move the io_policies into a
configuration device tree, instead of static structure in the code base.
This is currently an experimental feature.
- ``SDEI_IN_FCONF``: This flag determines whether to configure SDEI setup in
runtime using firmware configuration framework. The platform specific SDEI
shared and private events configuration is retrieved from device tree rather
than static C structures at compile time. This is currently an experimental
feature and is only supported if SDEI_SUPPORT build flag is enabled.
- ``SEC_INT_DESC_IN_FCONF``: This flag determines whether to configure Group 0
and Group1 secure interrupts using the firmware configuration framework. The
platform specific secure interrupt property descriptor is retrieved from
device tree in runtime rather than depending on static C structure at compile
time. This is currently an experimental feature.
- ``USE_ROMLIB``: This flag determines whether library at ROM will be used.
This feature creates a library of functions to be placed in ROM and thus
reduces SRAM usage. Refer to :ref:`Library at ROM` for further details. Default
is 0.
- ``V``: Verbose build. If assigned anything other than 0, the build commands
are printed. Default is 0.
- ``VERSION_STRING``: String used in the log output for each TF-A image.
Defaults to a string formed by concatenating the version number, build type
and build string.
- ``W``: Warning level. Some compiler warning options of interest have been
regrouped and put in the root Makefile. This flag can take the values 0 to 3,
each level enabling more warning options. Default is 0.
- ``WARMBOOT_ENABLE_DCACHE_EARLY`` : Boolean option to enable D-cache early on
the CPU after warm boot. This is applicable for platforms which do not
require interconnect programming to enable cache coherency (eg: single
cluster platforms). If this option is enabled, then warm boot path
enables D-caches immediately after enabling MMU. This option defaults to 0.
- ``SUPPORT_STACK_MEMTAG``: This flag determines whether to enable memory
tagging for stack or not. It accepts 2 values: ``yes`` and ``no``. The
default value of this flag is ``no``. Note this option must be enabled only
for ARM architecture greater than Armv8.5-A.
- ``ERRATA_SPECULATIVE_AT``: This flag enables/disables page table walk during
context restore as speculative AT instructions using an out-of-context
translation regime could cause subsequent requests to generate an incorrect
translation.
System registers are not updated during context save, hence this workaround
need not be applied in the context save path.
This boolean option enables errata for all below CPUs.
+---------+--------------+
| Errata | CPU |
+=========+==============+
| 1165522 | Cortex-A76 |
+---------+--------------+
| 1319367 | Cortex-A72 |
+---------+--------------+
| 1319537 | Cortex-A57 |
+---------+--------------+
| 1530923 | Cortex-A55 |
+---------+--------------+
| 1530924 | Cortex-A53 |
+---------+--------------+
GICv3 driver options
--------------------
GICv3 driver files are included using directive:
``include drivers/arm/gic/v3/gicv3.mk``
The driver can be configured with the following options set in the platform
makefile:
- ``GICV3_SUPPORT_GIC600``: Add support for the GIC-600 variants of GICv3.
Enabling this option will add runtime detection support for the
GIC-600, so is safe to select even for a GIC500 implementation.
This option defaults to 0.
- ``GICV3_IMPL_GIC600_MULTICHIP``: Selects GIC-600 variant with multichip
functionality. This option defaults to 0
- ``GICV3_OVERRIDE_DISTIF_PWR_OPS``: Allows override of default implementation
of ``arm_gicv3_distif_pre_save`` and ``arm_gicv3_distif_post_restore``
functions. This is required for FVP platform which need to simulate GIC save
and restore during SYSTEM_SUSPEND without powering down GIC. Default is 0.
- ``GIC_ENABLE_V4_EXTN`` : Enables GICv4 related changes in GICv3 driver.
This option defaults to 0.
- ``GIC_EXT_INTID``: When set to ``1``, GICv3 driver will support extended
PPI (1056-1119) and SPI (4096-5119) range. This option defaults to 0.
Debugging options
-----------------
To compile a debug version and make the build more verbose use
.. code:: shell
make PLAT=<platform> DEBUG=1 V=1 all
AArch64 GCC uses DWARF version 4 debugging symbols by default. Some tools (for
example DS-5) might not support this and may need an older version of DWARF
symbols to be emitted by GCC. This can be achieved by using the
``-gdwarf-<version>`` flag, with the version being set to 2 or 3. Setting the
version to 2 is recommended for DS-5 versions older than 5.16.
When debugging logic problems it might also be useful to disable all compiler
optimizations by using ``-O0``.
.. warning::
Using ``-O0`` could cause output images to be larger and base addresses
might need to be recalculated (see the **Memory layout on Arm development
platforms** section in the :ref:`Firmware Design`).
Extra debug options can be passed to the build system by setting ``CFLAGS`` or
``LDFLAGS``:
.. code:: shell
CFLAGS='-O0 -gdwarf-2' \
make PLAT=<platform> DEBUG=1 V=1 all
Note that using ``-Wl,`` style compilation driver options in ``CFLAGS`` will be
ignored as the linker is called directly.
It is also possible to introduce an infinite loop to help in debugging the
post-BL2 phase of TF-A. This can be done by rebuilding BL1 with the
``SPIN_ON_BL1_EXIT=1`` build flag. Refer to the :ref:`build_options_common`
section. In this case, the developer may take control of the target using a
debugger when indicated by the console output. When using DS-5, the following
commands can be used:
::
# Stop target execution
interrupt
#
# Prepare your debugging environment, e.g. set breakpoints
#
# Jump over the debug loop
set var $AARCH64::$Core::$PC = $AARCH64::$Core::$PC + 4
# Resume execution
continue
--------------
*Copyright (c) 2019-2020, Arm Limited. All rights reserved.*
