xref: /rk3399_ARM-atf/docs/getting_started/build-options.rst (revision 1fd685a74dd33c9c26a0ec0e82e7a5a378461362)
1Build Options
2=============
3
4The TF-A build system supports the following build options. Unless mentioned
5otherwise, these options are expected to be specified at the build command
6line and are not to be modified in any component makefiles. Note that the
7build system doesn't track dependency for build options. Therefore, if any of
8the build options are changed from a previous build, a clean build must be
9performed.
10
11.. _build_options_common:
12
13Common build options
14--------------------
15
16-  ``AARCH32_INSTRUCTION_SET``: Choose the AArch32 instruction set that the
17   compiler should use. Valid values are T32 and A32. It defaults to T32 due to
18   code having a smaller resulting size.
19
20-  ``AARCH32_SP`` : Choose the AArch32 Secure Payload component to be built as
21   as the BL32 image when ``ARCH=aarch32``. The value should be the path to the
22   directory containing the SP source, relative to the ``bl32/``; the directory
23   is expected to contain a makefile called ``<aarch32_sp-value>.mk``.
24
25-  ``AMU_RESTRICT_COUNTERS``: Register reads to the group 1 counters will return
26   zero at all but the highest implemented exception level.  Reads from the
27   memory mapped view are unaffected by this control.
28
29-  ``ARCH`` : Choose the target build architecture for TF-A. It can take either
30   ``aarch64`` or ``aarch32`` as values. By default, it is defined to
31   ``aarch64``.
32
33-  ``ARM_ARCH_FEATURE``: Optional Arm Architecture build option which specifies
34   one or more feature modifiers. This option has the form ``[no]feature+...``
35   and defaults to ``none``. It translates into compiler option
36   ``-march=armvX[.Y]-a+[no]feature+...``. See compiler's documentation for the
37   list of supported feature modifiers.
38
39-  ``ARM_ARCH_MAJOR``: The major version of Arm Architecture to target when
40   compiling TF-A. Its value must be numeric, and defaults to 8 . See also,
41   *Armv8 Architecture Extensions* and *Armv7 Architecture Extensions* in
42   :ref:`Firmware Design`.
43
44-  ``ARM_ARCH_MINOR``: The minor version of Arm Architecture to target when
45   compiling TF-A. Its value must be a numeric, and defaults to 0. See also,
46   *Armv8 Architecture Extensions* in :ref:`Firmware Design`.
47
48-  ``BL2``: This is an optional build option which specifies the path to BL2
49   image for the ``fip`` target. In this case, the BL2 in the TF-A will not be
50   built.
51
52-  ``BL2U``: This is an optional build option which specifies the path to
53   BL2U image. In this case, the BL2U in TF-A will not be built.
54
55-  ``BL2_AT_EL3``: This is an optional build option that enables the use of
56   BL2 at EL3 execution level.
57
58-  ``BL2_ENABLE_SP_LOAD``: Boolean option to enable loading SP packages from the
59   FIP. Automatically enabled if ``SP_LAYOUT_FILE`` is provided.
60
61-  ``BL2_IN_XIP_MEM``: In some use-cases BL2 will be stored in eXecute In Place
62   (XIP) memory, like BL1. In these use-cases, it is necessary to initialize
63   the RW sections in RAM, while leaving the RO sections in place. This option
64   enable this use-case. For now, this option is only supported when BL2_AT_EL3
65   is set to '1'.
66
67-  ``BL31``: This is an optional build option which specifies the path to
68   BL31 image for the ``fip`` target. In this case, the BL31 in TF-A will not
69   be built.
70
71-  ``BL31_KEY``: This option is used when ``GENERATE_COT=1``. It specifies the
72   file that contains the BL31 private key in PEM format. If ``SAVE_KEYS=1``,
73   this file name will be used to save the key.
74
75-  ``BL32``: This is an optional build option which specifies the path to
76   BL32 image for the ``fip`` target. In this case, the BL32 in TF-A will not
77   be built.
78
79-  ``BL32_EXTRA1``: This is an optional build option which specifies the path to
80   Trusted OS Extra1 image for the  ``fip`` target.
81
82-  ``BL32_EXTRA2``: This is an optional build option which specifies the path to
83   Trusted OS Extra2 image for the ``fip`` target.
84
85-  ``BL32_KEY``: This option is used when ``GENERATE_COT=1``. It specifies the
86   file that contains the BL32 private key in PEM format. If ``SAVE_KEYS=1``,
87   this file name will be used to save the key.
88
89-  ``BL33``: Path to BL33 image in the host file system. This is mandatory for
90   ``fip`` target in case TF-A BL2 is used.
91
92-  ``BL33_KEY``: This option is used when ``GENERATE_COT=1``. It specifies the
93   file that contains the BL33 private key in PEM format. If ``SAVE_KEYS=1``,
94   this file name will be used to save the key.
95
96-  ``BRANCH_PROTECTION``: Numeric value to enable ARMv8.3 Pointer Authentication
97   and ARMv8.5 Branch Target Identification support for TF-A BL images themselves.
98   If enabled, it is needed to use a compiler that supports the option
99   ``-mbranch-protection``. Selects the branch protection features to use:
100-  0: Default value turns off all types of branch protection
101-  1: Enables all types of branch protection features
102-  2: Return address signing to its standard level
103-  3: Extend the signing to include leaf functions
104-  4: Turn on branch target identification mechanism
105
106   The table below summarizes ``BRANCH_PROTECTION`` values, GCC compilation options
107   and resulting PAuth/BTI features.
108
109   +-------+--------------+-------+-----+
110   | Value |  GCC option  | PAuth | BTI |
111   +=======+==============+=======+=====+
112   |   0   |     none     |   N   |  N  |
113   +-------+--------------+-------+-----+
114   |   1   |   standard   |   Y   |  Y  |
115   +-------+--------------+-------+-----+
116   |   2   |   pac-ret    |   Y   |  N  |
117   +-------+--------------+-------+-----+
118   |   3   | pac-ret+leaf |   Y   |  N  |
119   +-------+--------------+-------+-----+
120   |   4   |     bti      |   N   |  Y  |
121   +-------+--------------+-------+-----+
122
123   This option defaults to 0 and this is an experimental feature.
124   Note that Pointer Authentication is enabled for Non-secure world
125   irrespective of the value of this option if the CPU supports it.
126
127-  ``BUILD_MESSAGE_TIMESTAMP``: String used to identify the time and date of the
128   compilation of each build. It must be set to a C string (including quotes
129   where applicable). Defaults to a string that contains the time and date of
130   the compilation.
131
132-  ``BUILD_STRING``: Input string for VERSION_STRING, which allows the TF-A
133   build to be uniquely identified. Defaults to the current git commit id.
134
135-  ``BUILD_BASE``: Output directory for the build. Defaults to ``./build``
136
137-  ``CFLAGS``: Extra user options appended on the compiler's command line in
138   addition to the options set by the build system.
139
140-  ``COLD_BOOT_SINGLE_CPU``: This option indicates whether the platform may
141   release several CPUs out of reset. It can take either 0 (several CPUs may be
142   brought up) or 1 (only one CPU will ever be brought up during cold reset).
143   Default is 0. If the platform always brings up a single CPU, there is no
144   need to distinguish between primary and secondary CPUs and the boot path can
145   be optimised. The ``plat_is_my_cpu_primary()`` and
146   ``plat_secondary_cold_boot_setup()`` platform porting interfaces do not need
147   to be implemented in this case.
148
149-  ``COT``: When Trusted Boot is enabled, selects the desired chain of trust.
150   Defaults to ``tbbr``.
151
152-  ``CRASH_REPORTING``: A non-zero value enables a console dump of processor
153   register state when an unexpected exception occurs during execution of
154   BL31. This option defaults to the value of ``DEBUG`` - i.e. by default
155   this is only enabled for a debug build of the firmware.
156
157-  ``CREATE_KEYS``: This option is used when ``GENERATE_COT=1``. It tells the
158   certificate generation tool to create new keys in case no valid keys are
159   present or specified. Allowed options are '0' or '1'. Default is '1'.
160
161-  ``CTX_INCLUDE_AARCH32_REGS`` : Boolean option that, when set to 1, will cause
162   the AArch32 system registers to be included when saving and restoring the
163   CPU context. The option must be set to 0 for AArch64-only platforms (that
164   is on hardware that does not implement AArch32, or at least not at EL1 and
165   higher ELs). Default value is 1.
166
167-  ``CTX_INCLUDE_EL2_REGS`` : This boolean option provides context save/restore
168   operations when entering/exiting an EL2 execution context. This is of primary
169   interest when Armv8.4-SecEL2 extension is implemented. Default is 0 (disabled).
170   This option must be equal to 1 (enabled) when ``SPD=spmd`` and
171   ``SPMD_SPM_AT_SEL2`` is set.
172
173-  ``CTX_INCLUDE_FPREGS``: Boolean option that, when set to 1, will cause the FP
174   registers to be included when saving and restoring the CPU context. Default
175   is 0.
176
177-  ``CTX_INCLUDE_NEVE_REGS``: Boolean option that, when set to 1, will cause the
178   Armv8.4-NV registers to be saved/restored when entering/exiting an EL2
179   execution context. Default value is 0.
180
181-  ``CTX_INCLUDE_PAUTH_REGS``: Boolean option that, when set to 1, enables
182   Pointer Authentication for Secure world. This will cause the ARMv8.3-PAuth
183   registers to be included when saving and restoring the CPU context as
184   part of world switch. Default value is 0 and this is an experimental feature.
185   Note that Pointer Authentication is enabled for Non-secure world irrespective
186   of the value of this flag if the CPU supports it.
187
188-  ``DEBUG``: Chooses between a debug and release build. It can take either 0
189   (release) or 1 (debug) as values. 0 is the default.
190
191-  ``DECRYPTION_SUPPORT``: This build flag enables the user to select the
192   authenticated decryption algorithm to be used to decrypt firmware/s during
193   boot. It accepts 2 values: ``aes_gcm`` and ``none``. The default value of
194   this flag is ``none`` to disable firmware decryption which is an optional
195   feature as per TBBR. Also, it is an experimental feature.
196
197-  ``DISABLE_BIN_GENERATION``: Boolean option to disable the generation
198   of the binary image. If set to 1, then only the ELF image is built.
199   0 is the default.
200
201-  ``DISABLE_MTPMU``: Boolean option to disable FEAT_MTPMU if implemented
202   (Armv8.6 onwards). Its default value is 0 to keep consistency with platforms
203   that do not implement FEAT_MTPMU. For more information on FEAT_MTPMU,
204   check the latest Arm ARM.
205
206-  ``DYN_DISABLE_AUTH``: Provides the capability to dynamically disable Trusted
207   Board Boot authentication at runtime. This option is meant to be enabled only
208   for development platforms. ``TRUSTED_BOARD_BOOT`` flag must be set if this
209   flag has to be enabled. 0 is the default.
210
211-  ``E``: Boolean option to make warnings into errors. Default is 1.
212
213-  ``EL3_PAYLOAD_BASE``: This option enables booting an EL3 payload instead of
214   the normal boot flow. It must specify the entry point address of the EL3
215   payload. Please refer to the "Booting an EL3 payload" section for more
216   details.
217
218-  ``ENABLE_AMU``: Boolean option to enable Activity Monitor Unit extensions.
219   This is an optional architectural feature available on v8.4 onwards. Some
220   v8.2 implementations also implement an AMU and this option can be used to
221   enable this feature on those systems as well. Default is 0.
222
223-  ``ENABLE_AMU_AUXILIARY_COUNTERS``: Enables support for AMU auxiliary counters
224   (also known as group 1 counters). These are implementation-defined counters,
225   and as such require additional platform configuration. Default is 0.
226
227-  ``ENABLE_ASSERTIONS``: This option controls whether or not calls to ``assert()``
228   are compiled out. For debug builds, this option defaults to 1, and calls to
229   ``assert()`` are left in place. For release builds, this option defaults to 0
230   and calls to ``assert()`` function are compiled out. This option can be set
231   independently of ``DEBUG``. It can also be used to hide any auxiliary code
232   that is only required for the assertion and does not fit in the assertion
233   itself.
234
235-  ``ENABLE_BACKTRACE``: This option controls whether to enable backtrace
236   dumps or not. It is supported in both AArch64 and AArch32. However, in
237   AArch32 the format of the frame records are not defined in the AAPCS and they
238   are defined by the implementation. This implementation of backtrace only
239   supports the format used by GCC when T32 interworking is disabled. For this
240   reason enabling this option in AArch32 will force the compiler to only
241   generate A32 code. This option is enabled by default only in AArch64 debug
242   builds, but this behaviour can be overridden in each platform's Makefile or
243   in the build command line.
244
245-  ``ENABLE_FEAT_HCX``: This option sets the bit SCR_EL3.HXEn in EL3 to allow
246   access to HCRX_EL2 (extended hypervisor control register) from EL2 as well as
247   adding HCRX_EL2 to the EL2 context save/restore operations.
248
249-  ``ENABLE_LTO``: Boolean option to enable Link Time Optimization (LTO)
250   support in GCC for TF-A. This option is currently only supported for
251   AArch64. Default is 0.
252
253-  ``ENABLE_MPAM_FOR_LOWER_ELS``: Boolean option to enable lower ELs to use MPAM
254   feature. MPAM is an optional Armv8.4 extension that enables various memory
255   system components and resources to define partitions; software running at
256   various ELs can assign themselves to desired partition to control their
257   performance aspects.
258
259   When this option is set to ``1``, EL3 allows lower ELs to access their own
260   MPAM registers without trapping into EL3. This option doesn't make use of
261   partitioning in EL3, however. Platform initialisation code should configure
262   and use partitions in EL3 as required. This option defaults to ``0``.
263
264-  ``ENABLE_PIE``: Boolean option to enable Position Independent Executable(PIE)
265   support within generic code in TF-A. This option is currently only supported
266   in BL2_AT_EL3, BL31, and BL32 (TSP) for AARCH64 binaries, and in BL32
267   (SP_min) for AARCH32. Default is 0.
268
269-  ``ENABLE_PMF``: Boolean option to enable support for optional Performance
270   Measurement Framework(PMF). Default is 0.
271
272-  ``ENABLE_PSCI_STAT``: Boolean option to enable support for optional PSCI
273   functions ``PSCI_STAT_RESIDENCY`` and ``PSCI_STAT_COUNT``. Default is 0.
274   In the absence of an alternate stat collection backend, ``ENABLE_PMF`` must
275   be enabled. If ``ENABLE_PMF`` is set, the residency statistics are tracked in
276   software.
277
278- ``ENABLE_RME``: Boolean option to enable support for the ARMv9 Realm
279   Management Extension. Default value is 0. This is currently an experimental
280   feature.
281
282-  ``ENABLE_RUNTIME_INSTRUMENTATION``: Boolean option to enable runtime
283   instrumentation which injects timestamp collection points into TF-A to
284   allow runtime performance to be measured. Currently, only PSCI is
285   instrumented. Enabling this option enables the ``ENABLE_PMF`` build option
286   as well. Default is 0.
287
288-  ``ENABLE_SPE_FOR_LOWER_ELS`` : Boolean option to enable Statistical Profiling
289   extensions. This is an optional architectural feature for AArch64.
290   The default is 1 but is automatically disabled when the target architecture
291   is AArch32.
292
293-  ``ENABLE_SVE_FOR_NS``: Boolean option to enable Scalable Vector Extension
294   (SVE) for the Non-secure world only. SVE is an optional architectural feature
295   for AArch64. Note that when SVE is enabled for the Non-secure world, access
296   to SIMD and floating-point functionality from the Secure world is disabled by
297   default and controlled with ENABLE_SVE_FOR_SWD.
298   This is to avoid corruption of the Non-secure world data in the Z-registers
299   which are aliased by the SIMD and FP registers. The build option is not
300   compatible with the ``CTX_INCLUDE_FPREGS`` build option, and will raise an
301   assert on platforms where SVE is implemented and ``ENABLE_SVE_FOR_NS`` set to
302   1. The default is 1 but is automatically disabled when the target
303   architecture is AArch32.
304
305-  ``ENABLE_SVE_FOR_SWD``: Boolean option to enable SVE for the Secure world.
306   SVE is an optional architectural feature for AArch64. Note that this option
307   requires ENABLE_SVE_FOR_NS to be enabled.  The default is 0 and it is
308   automatically disabled when the target architecture is AArch32.
309
310-  ``ENABLE_STACK_PROTECTOR``: String option to enable the stack protection
311   checks in GCC. Allowed values are "all", "strong", "default" and "none". The
312   default value is set to "none". "strong" is the recommended stack protection
313   level if this feature is desired. "none" disables the stack protection. For
314   all values other than "none", the ``plat_get_stack_protector_canary()``
315   platform hook needs to be implemented. The value is passed as the last
316   component of the option ``-fstack-protector-$ENABLE_STACK_PROTECTOR``.
317
318-  ``ENCRYPT_BL31``: Binary flag to enable encryption of BL31 firmware. This
319   flag depends on ``DECRYPTION_SUPPORT`` build flag which is marked as
320   experimental.
321
322-  ``ENCRYPT_BL32``: Binary flag to enable encryption of Secure BL32 payload.
323   This flag depends on ``DECRYPTION_SUPPORT`` build flag which is marked as
324   experimental.
325
326-  ``ENC_KEY``: A 32-byte (256-bit) symmetric key in hex string format. It could
327   either be SSK or BSSK depending on ``FW_ENC_STATUS`` flag. This value depends
328   on ``DECRYPTION_SUPPORT`` build flag which is marked as experimental.
329
330-  ``ENC_NONCE``: A 12-byte (96-bit) encryption nonce or Initialization Vector
331   (IV) in hex string format. This value depends on ``DECRYPTION_SUPPORT``
332   build flag which is marked as experimental.
333
334-  ``ERROR_DEPRECATED``: This option decides whether to treat the usage of
335   deprecated platform APIs, helper functions or drivers within Trusted
336   Firmware as error. It can take the value 1 (flag the use of deprecated
337   APIs as error) or 0. The default is 0.
338
339-  ``EL3_EXCEPTION_HANDLING``: When set to ``1``, enable handling of exceptions
340   targeted at EL3. When set ``0`` (default), no exceptions are expected or
341   handled at EL3, and a panic will result. This is supported only for AArch64
342   builds.
343
344-  ``EVENT_LOG_LEVEL``: Chooses the log level to use for Measured Boot when
345   ``MEASURED_BOOT`` is enabled. For a list of valid values, see ``LOG_LEVEL``.
346   Default value is 40 (LOG_LEVEL_INFO).
347
348-  ``FAULT_INJECTION_SUPPORT``: ARMv8.4 extensions introduced support for fault
349   injection from lower ELs, and this build option enables lower ELs to use
350   Error Records accessed via System Registers to inject faults. This is
351   applicable only to AArch64 builds.
352
353   This feature is intended for testing purposes only, and is advisable to keep
354   disabled for production images.
355
356-  ``FIP_NAME``: This is an optional build option which specifies the FIP
357   filename for the ``fip`` target. Default is ``fip.bin``.
358
359-  ``FWU_FIP_NAME``: This is an optional build option which specifies the FWU
360   FIP filename for the ``fwu_fip`` target. Default is ``fwu_fip.bin``.
361
362-  ``FW_ENC_STATUS``: Top level firmware's encryption numeric flag, values:
363
364   ::
365
366     0: Encryption is done with Secret Symmetric Key (SSK) which is common
367        for a class of devices.
368     1: Encryption is done with Binding Secret Symmetric Key (BSSK) which is
369        unique per device.
370
371   This flag depends on ``DECRYPTION_SUPPORT`` build flag which is marked as
372   experimental.
373
374-  ``GENERATE_COT``: Boolean flag used to build and execute the ``cert_create``
375   tool to create certificates as per the Chain of Trust described in
376   :ref:`Trusted Board Boot`. The build system then calls ``fiptool`` to
377   include the certificates in the FIP and FWU_FIP. Default value is '0'.
378
379   Specify both ``TRUSTED_BOARD_BOOT=1`` and ``GENERATE_COT=1`` to include support
380   for the Trusted Board Boot feature in the BL1 and BL2 images, to generate
381   the corresponding certificates, and to include those certificates in the
382   FIP and FWU_FIP.
383
384   Note that if ``TRUSTED_BOARD_BOOT=0`` and ``GENERATE_COT=1``, the BL1 and BL2
385   images will not include support for Trusted Board Boot. The FIP will still
386   include the corresponding certificates. This FIP can be used to verify the
387   Chain of Trust on the host machine through other mechanisms.
388
389   Note that if ``TRUSTED_BOARD_BOOT=1`` and ``GENERATE_COT=0``, the BL1 and BL2
390   images will include support for Trusted Board Boot, but the FIP and FWU_FIP
391   will not include the corresponding certificates, causing a boot failure.
392
393-  ``GICV2_G0_FOR_EL3``: Unlike GICv3, the GICv2 architecture doesn't have
394   inherent support for specific EL3 type interrupts. Setting this build option
395   to ``1`` assumes GICv2 *Group 0* interrupts are expected to target EL3, both
396   by :ref:`platform abstraction layer<platform Interrupt Controller API>` and
397   :ref:`Interrupt Management Framework<Interrupt Management Framework>`.
398   This allows GICv2 platforms to enable features requiring EL3 interrupt type.
399   This also means that all GICv2 Group 0 interrupts are delivered to EL3, and
400   the Secure Payload interrupts needs to be synchronously handed over to Secure
401   EL1 for handling. The default value of this option is ``0``, which means the
402   Group 0 interrupts are assumed to be handled by Secure EL1.
403
404-  ``HANDLE_EA_EL3_FIRST``: When set to ``1``, External Aborts and SError
405   Interrupts will be always trapped in EL3 i.e. in BL31 at runtime. When set to
406   ``0`` (default), these exceptions will be trapped in the current exception
407   level (or in EL1 if the current exception level is EL0).
408
409-  ``HW_ASSISTED_COHERENCY``: On most Arm systems to-date, platform-specific
410   software operations are required for CPUs to enter and exit coherency.
411   However, newer systems exist where CPUs' entry to and exit from coherency
412   is managed in hardware. Such systems require software to only initiate these
413   operations, and the rest is managed in hardware, minimizing active software
414   management. In such systems, this boolean option enables TF-A to carry out
415   build and run-time optimizations during boot and power management operations.
416   This option defaults to 0 and if it is enabled, then it implies
417   ``WARMBOOT_ENABLE_DCACHE_EARLY`` is also enabled.
418
419   If this flag is disabled while the platform which TF-A is compiled for
420   includes cores that manage coherency in hardware, then a compilation error is
421   generated. This is based on the fact that a system cannot have, at the same
422   time, cores that manage coherency in hardware and cores that don't. In other
423   words, a platform cannot have, at the same time, cores that require
424   ``HW_ASSISTED_COHERENCY=1`` and cores that require
425   ``HW_ASSISTED_COHERENCY=0``.
426
427   Note that, when ``HW_ASSISTED_COHERENCY`` is enabled, version 2 of
428   translation library (xlat tables v2) must be used; version 1 of translation
429   library is not supported.
430
431-  ``INVERTED_MEMMAP``: memmap tool print by default lower addresses at the
432   bottom, higher addresses at the top. This build flag can be set to '1' to
433   invert this behavior. Lower addresses will be printed at the top and higher
434   addresses at the bottom.
435
436-  ``JUNO_AARCH32_EL3_RUNTIME``: This build flag enables you to execute EL3
437   runtime software in AArch32 mode, which is required to run AArch32 on Juno.
438   By default this flag is set to '0'. Enabling this flag builds BL1 and BL2 in
439   AArch64 and facilitates the loading of ``SP_MIN`` and BL33 as AArch32 executable
440   images.
441
442-  ``KEY_ALG``: This build flag enables the user to select the algorithm to be
443   used for generating the PKCS keys and subsequent signing of the certificate.
444   It accepts 3 values: ``rsa``, ``rsa_1_5`` and ``ecdsa``. The option
445   ``rsa_1_5`` is the legacy PKCS#1 RSA 1.5 algorithm which is not TBBR
446   compliant and is retained only for compatibility. The default value of this
447   flag is ``rsa`` which is the TBBR compliant PKCS#1 RSA 2.1 scheme.
448
449-  ``KEY_SIZE``: This build flag enables the user to select the key size for
450   the algorithm specified by ``KEY_ALG``. The valid values for ``KEY_SIZE``
451   depend on the chosen algorithm and the cryptographic module.
452
453   +-----------+------------------------------------+
454   |  KEY_ALG  |        Possible key sizes          |
455   +===========+====================================+
456   |    rsa    | 1024 , 2048 (default), 3072, 4096* |
457   +-----------+------------------------------------+
458   |   ecdsa   |            unavailable             |
459   +-----------+------------------------------------+
460
461   * Only 2048 bits size is available with CryptoCell 712 SBROM release 1.
462     Only 3072 bits size is available with CryptoCell 712 SBROM release 2.
463
464-  ``HASH_ALG``: This build flag enables the user to select the secure hash
465   algorithm. It accepts 3 values: ``sha256``, ``sha384`` and ``sha512``.
466   The default value of this flag is ``sha256``.
467
468-  ``LDFLAGS``: Extra user options appended to the linkers' command line in
469   addition to the one set by the build system.
470
471-  ``LOG_LEVEL``: Chooses the log level, which controls the amount of console log
472   output compiled into the build. This should be one of the following:
473
474   ::
475
476       0  (LOG_LEVEL_NONE)
477       10 (LOG_LEVEL_ERROR)
478       20 (LOG_LEVEL_NOTICE)
479       30 (LOG_LEVEL_WARNING)
480       40 (LOG_LEVEL_INFO)
481       50 (LOG_LEVEL_VERBOSE)
482
483   All log output up to and including the selected log level is compiled into
484   the build. The default value is 40 in debug builds and 20 in release builds.
485
486-  ``MEASURED_BOOT``: Boolean flag to include support for the Measured Boot
487   feature. If this flag is enabled ``TRUSTED_BOARD_BOOT`` must be set as well
488   in order to provide trust that the code taking the measurements and recording
489   them has not been tampered with.
490
491   This option defaults to 0 and is an experimental feature in the stage of
492   development.
493
494-  ``NON_TRUSTED_WORLD_KEY``: This option is used when ``GENERATE_COT=1``. It
495   specifies the file that contains the Non-Trusted World private key in PEM
496   format. If ``SAVE_KEYS=1``, this file name will be used to save the key.
497
498-  ``NS_BL2U``: Path to NS_BL2U image in the host file system. This image is
499   optional. It is only needed if the platform makefile specifies that it
500   is required in order to build the ``fwu_fip`` target.
501
502-  ``NS_TIMER_SWITCH``: Enable save and restore for non-secure timer register
503   contents upon world switch. It can take either 0 (don't save and restore) or
504   1 (do save and restore). 0 is the default. An SPD may set this to 1 if it
505   wants the timer registers to be saved and restored.
506
507-  ``OVERRIDE_LIBC``: This option allows platforms to override the default libc
508   for the BL image. It can be either 0 (include) or 1 (remove). The default
509   value is 0.
510
511-  ``PL011_GENERIC_UART``: Boolean option to indicate the PL011 driver that
512   the underlying hardware is not a full PL011 UART but a minimally compliant
513   generic UART, which is a subset of the PL011. The driver will not access
514   any register that is not part of the SBSA generic UART specification.
515   Default value is 0 (a full PL011 compliant UART is present).
516
517-  ``PLAT``: Choose a platform to build TF-A for. The chosen platform name
518   must be subdirectory of any depth under ``plat/``, and must contain a
519   platform makefile named ``platform.mk``. For example, to build TF-A for the
520   Arm Juno board, select PLAT=juno.
521
522-  ``PRELOADED_BL33_BASE``: This option enables booting a preloaded BL33 image
523   instead of the normal boot flow. When defined, it must specify the entry
524   point address for the preloaded BL33 image. This option is incompatible with
525   ``EL3_PAYLOAD_BASE``. If both are defined, ``EL3_PAYLOAD_BASE`` has priority
526   over ``PRELOADED_BL33_BASE``.
527
528-  ``PROGRAMMABLE_RESET_ADDRESS``: This option indicates whether the reset
529   vector address can be programmed or is fixed on the platform. It can take
530   either 0 (fixed) or 1 (programmable). Default is 0. If the platform has a
531   programmable reset address, it is expected that a CPU will start executing
532   code directly at the right address, both on a cold and warm reset. In this
533   case, there is no need to identify the entrypoint on boot and the boot path
534   can be optimised. The ``plat_get_my_entrypoint()`` platform porting interface
535   does not need to be implemented in this case.
536
537-  ``PSCI_EXTENDED_STATE_ID``: As per PSCI1.0 Specification, there are 2 formats
538   possible for the PSCI power-state parameter: original and extended State-ID
539   formats. This flag if set to 1, configures the generic PSCI layer to use the
540   extended format. The default value of this flag is 0, which means by default
541   the original power-state format is used by the PSCI implementation. This flag
542   should be specified by the platform makefile and it governs the return value
543   of PSCI_FEATURES API for CPU_SUSPEND smc function id. When this option is
544   enabled on Arm platforms, the option ``ARM_RECOM_STATE_ID_ENC`` needs to be
545   set to 1 as well.
546
547-  ``RAS_EXTENSION``: When set to ``1``, enable Armv8.2 RAS features. RAS features
548   are an optional extension for pre-Armv8.2 CPUs, but are mandatory for Armv8.2
549   or later CPUs.
550
551   When ``RAS_EXTENSION`` is set to ``1``, ``HANDLE_EA_EL3_FIRST`` must also be
552   set to ``1``.
553
554   This option is disabled by default.
555
556-  ``RESET_TO_BL31``: Enable BL31 entrypoint as the CPU reset vector instead
557   of the BL1 entrypoint. It can take the value 0 (CPU reset to BL1
558   entrypoint) or 1 (CPU reset to BL31 entrypoint).
559   The default value is 0.
560
561-  ``RESET_TO_SP_MIN``: SP_MIN is the minimal AArch32 Secure Payload provided
562   in TF-A. This flag configures SP_MIN entrypoint as the CPU reset vector
563   instead of the BL1 entrypoint. It can take the value 0 (CPU reset to BL1
564   entrypoint) or 1 (CPU reset to SP_MIN entrypoint). The default value is 0.
565
566-  ``ROT_KEY``: This option is used when ``GENERATE_COT=1``. It specifies the
567   file that contains the ROT private key in PEM format and enforces public key
568   hash generation. If ``SAVE_KEYS=1``, this
569   file name will be used to save the key.
570
571-  ``SAVE_KEYS``: This option is used when ``GENERATE_COT=1``. It tells the
572   certificate generation tool to save the keys used to establish the Chain of
573   Trust. Allowed options are '0' or '1'. Default is '0' (do not save).
574
575-  ``SCP_BL2``: Path to SCP_BL2 image in the host file system. This image is optional.
576   If a SCP_BL2 image is present then this option must be passed for the ``fip``
577   target.
578
579-  ``SCP_BL2_KEY``: This option is used when ``GENERATE_COT=1``. It specifies the
580   file that contains the SCP_BL2 private key in PEM format. If ``SAVE_KEYS=1``,
581   this file name will be used to save the key.
582
583-  ``SCP_BL2U``: Path to SCP_BL2U image in the host file system. This image is
584   optional. It is only needed if the platform makefile specifies that it
585   is required in order to build the ``fwu_fip`` target.
586
587-  ``SDEI_SUPPORT``: Setting this to ``1`` enables support for Software
588   Delegated Exception Interface to BL31 image. This defaults to ``0``.
589
590   When set to ``1``, the build option ``EL3_EXCEPTION_HANDLING`` must also be
591   set to ``1``.
592
593-  ``SEPARATE_CODE_AND_RODATA``: Whether code and read-only data should be
594   isolated on separate memory pages. This is a trade-off between security and
595   memory usage. See "Isolating code and read-only data on separate memory
596   pages" section in :ref:`Firmware Design`. This flag is disabled by default
597   and affects all BL images.
598
599-  ``SEPARATE_NOBITS_REGION``: Setting this option to ``1`` allows the NOBITS
600   sections of BL31 (.bss, stacks, page tables, and coherent memory) to be
601   allocated in RAM discontiguous from the loaded firmware image. When set, the
602   platform is expected to provide definitions for ``BL31_NOBITS_BASE`` and
603   ``BL31_NOBITS_LIMIT``. When the option is ``0`` (the default), NOBITS
604   sections are placed in RAM immediately following the loaded firmware image.
605
606-  ``SMC_PCI_SUPPORT``: This option allows platforms to handle PCI configuration
607   access requests via a standard SMCCC defined in `DEN0115`_. When combined with
608   UEFI+ACPI this can provide a certain amount of OS forward compatibility
609   with newer platforms that aren't ECAM compliant.
610
611-  ``SPD``: Choose a Secure Payload Dispatcher component to be built into TF-A.
612   This build option is only valid if ``ARCH=aarch64``. The value should be
613   the path to the directory containing the SPD source, relative to
614   ``services/spd/``; the directory is expected to contain a makefile called
615   ``<spd-value>.mk``. The SPM Dispatcher standard service is located in
616   services/std_svc/spmd and enabled by ``SPD=spmd``. The SPM Dispatcher
617   cannot be enabled when the ``SPM_MM`` option is enabled.
618
619-  ``SPIN_ON_BL1_EXIT``: This option introduces an infinite loop in BL1. It can
620   take either 0 (no loop) or 1 (add a loop). 0 is the default. This loop stops
621   execution in BL1 just before handing over to BL31. At this point, all
622   firmware images have been loaded in memory, and the MMU and caches are
623   turned off. Refer to the "Debugging options" section for more details.
624
625-  ``SPMD_SPM_AT_SEL2`` : this boolean option is used jointly with the SPM
626   Dispatcher option (``SPD=spmd``). When enabled (1) it indicates the SPMC
627   component runs at the S-EL2 execution state provided by the Armv8.4-SecEL2
628   extension. This is the default when enabling the SPM Dispatcher. When
629   disabled (0) it indicates the SPMC component runs at the S-EL1 execution
630   state. This latter configuration supports pre-Armv8.4 platforms (aka not
631   implementing the Armv8.4-SecEL2 extension).
632
633-  ``SPM_MM`` : Boolean option to enable the Management Mode (MM)-based Secure
634   Partition Manager (SPM) implementation. The default value is ``0``
635   (disabled). This option cannot be enabled (``1``) when SPM Dispatcher is
636   enabled (``SPD=spmd``).
637
638-  ``SP_LAYOUT_FILE``: Platform provided path to JSON file containing the
639   description of secure partitions. The build system will parse this file and
640   package all secure partition blobs into the FIP. This file is not
641   necessarily part of TF-A tree. Only available when ``SPD=spmd``.
642
643-  ``SP_MIN_WITH_SECURE_FIQ``: Boolean flag to indicate the SP_MIN handles
644   secure interrupts (caught through the FIQ line). Platforms can enable
645   this directive if they need to handle such interruption. When enabled,
646   the FIQ are handled in monitor mode and non secure world is not allowed
647   to mask these events. Platforms that enable FIQ handling in SP_MIN shall
648   implement the api ``sp_min_plat_fiq_handler()``. The default value is 0.
649
650-  ``TRUSTED_BOARD_BOOT``: Boolean flag to include support for the Trusted Board
651   Boot feature. When set to '1', BL1 and BL2 images include support to load
652   and verify the certificates and images in a FIP, and BL1 includes support
653   for the Firmware Update. The default value is '0'. Generation and inclusion
654   of certificates in the FIP and FWU_FIP depends upon the value of the
655   ``GENERATE_COT`` option.
656
657   .. warning::
658      This option depends on ``CREATE_KEYS`` to be enabled. If the keys
659      already exist in disk, they will be overwritten without further notice.
660
661-  ``TRUSTED_WORLD_KEY``: This option is used when ``GENERATE_COT=1``. It
662   specifies the file that contains the Trusted World private key in PEM
663   format. If ``SAVE_KEYS=1``, this file name will be used to save the key.
664
665-  ``TSP_INIT_ASYNC``: Choose BL32 initialization method as asynchronous or
666   synchronous, (see "Initializing a BL32 Image" section in
667   :ref:`Firmware Design`). It can take the value 0 (BL32 is initialized using
668   synchronous method) or 1 (BL32 is initialized using asynchronous method).
669   Default is 0.
670
671-  ``TSP_NS_INTR_ASYNC_PREEMPT``: A non zero value enables the interrupt
672   routing model which routes non-secure interrupts asynchronously from TSP
673   to EL3 causing immediate preemption of TSP. The EL3 is responsible
674   for saving and restoring the TSP context in this routing model. The
675   default routing model (when the value is 0) is to route non-secure
676   interrupts to TSP allowing it to save its context and hand over
677   synchronously to EL3 via an SMC.
678
679   .. note::
680      When ``EL3_EXCEPTION_HANDLING`` is ``1``, ``TSP_NS_INTR_ASYNC_PREEMPT``
681      must also be set to ``1``.
682
683-  ``USE_ARM_LINK``: This flag determines whether to enable support for ARM
684   linker. When the ``LINKER`` build variable points to the armlink linker,
685   this flag is enabled automatically. To enable support for armlink, platforms
686   will have to provide a scatter file for the BL image. Currently, Tegra
687   platforms use the armlink support to compile BL3-1 images.
688
689-  ``USE_COHERENT_MEM``: This flag determines whether to include the coherent
690   memory region in the BL memory map or not (see "Use of Coherent memory in
691   TF-A" section in :ref:`Firmware Design`). It can take the value 1
692   (Coherent memory region is included) or 0 (Coherent memory region is
693   excluded). Default is 1.
694
695-  ``USE_DEBUGFS``: When set to 1 this option activates an EXPERIMENTAL feature
696   exposing a virtual filesystem interface through BL31 as a SiP SMC function.
697   Default is 0.
698
699-  ``ARM_IO_IN_DTB``: This flag determines whether to use IO based on the
700   firmware configuration framework. This will move the io_policies into a
701   configuration device tree, instead of static structure in the code base.
702   This is currently an experimental feature.
703
704-  ``COT_DESC_IN_DTB``: This flag determines whether to create COT descriptors
705   at runtime using fconf. If this flag is enabled, COT descriptors are
706   statically captured in tb_fw_config file in the form of device tree nodes
707   and properties. Currently, COT descriptors used by BL2 are moved to the
708   device tree and COT descriptors used by BL1 are retained in the code
709   base statically. This is currently an experimental feature.
710
711-  ``SDEI_IN_FCONF``: This flag determines whether to configure SDEI setup in
712   runtime using firmware configuration framework. The platform specific SDEI
713   shared and private events configuration is retrieved from device tree rather
714   than static C structures at compile time. This is currently an experimental
715   feature and is only supported if SDEI_SUPPORT build flag is enabled.
716
717-  ``SEC_INT_DESC_IN_FCONF``: This flag determines whether to configure Group 0
718   and Group1 secure interrupts using the firmware configuration framework. The
719   platform specific secure interrupt property descriptor is retrieved from
720   device tree in runtime rather than depending on static C structure at compile
721   time. This is currently an experimental feature.
722
723-  ``USE_ROMLIB``: This flag determines whether library at ROM will be used.
724   This feature creates a library of functions to be placed in ROM and thus
725   reduces SRAM usage. Refer to :ref:`Library at ROM` for further details. Default
726   is 0.
727
728-  ``V``: Verbose build. If assigned anything other than 0, the build commands
729   are printed. Default is 0.
730
731-  ``VERSION_STRING``: String used in the log output for each TF-A image.
732   Defaults to a string formed by concatenating the version number, build type
733   and build string.
734
735-  ``W``: Warning level. Some compiler warning options of interest have been
736   regrouped and put in the root Makefile. This flag can take the values 0 to 3,
737   each level enabling more warning options. Default is 0.
738
739-  ``WARMBOOT_ENABLE_DCACHE_EARLY`` : Boolean option to enable D-cache early on
740   the CPU after warm boot. This is applicable for platforms which do not
741   require interconnect programming to enable cache coherency (eg: single
742   cluster platforms). If this option is enabled, then warm boot path
743   enables D-caches immediately after enabling MMU. This option defaults to 0.
744
745-  ``SUPPORT_STACK_MEMTAG``: This flag determines whether to enable memory
746   tagging for stack or not. It accepts 2 values: ``yes`` and ``no``. The
747   default value of this flag is ``no``. Note this option must be enabled only
748   for ARM architecture greater than Armv8.5-A.
749
750-  ``ERRATA_SPECULATIVE_AT``: This flag determines whether to enable ``AT``
751   speculative errata workaround or not. It accepts 2 values: ``1`` and ``0``.
752   The default value of this flag is ``0``.
753
754   ``AT`` speculative errata workaround disables stage1 page table walk for
755   lower ELs (EL1 and EL0) in EL3 so that ``AT`` speculative fetch at any point
756   produces either the correct result or failure without TLB allocation.
757
758   This boolean option enables errata for all below CPUs.
759
760   +---------+--------------+-------------------------+
761   | Errata  |      CPU     |     Workaround Define   |
762   +=========+==============+=========================+
763   | 1165522 |  Cortex-A76  |  ``ERRATA_A76_1165522`` |
764   +---------+--------------+-------------------------+
765   | 1319367 |  Cortex-A72  |  ``ERRATA_A72_1319367`` |
766   +---------+--------------+-------------------------+
767   | 1319537 |  Cortex-A57  |  ``ERRATA_A57_1319537`` |
768   +---------+--------------+-------------------------+
769   | 1530923 |  Cortex-A55  |  ``ERRATA_A55_1530923`` |
770   +---------+--------------+-------------------------+
771   | 1530924 |  Cortex-A53  |  ``ERRATA_A53_1530924`` |
772   +---------+--------------+-------------------------+
773
774   .. note::
775      This option is enabled by build only if platform sets any of above defines
776      mentioned in ’Workaround Define' column in the table.
777      If this option is enabled for the EL3 software then EL2 software also must
778      implement this workaround due to the behaviour of the errata mentioned
779      in new SDEN document which will get published soon.
780
781- ``RAS_TRAP_LOWER_EL_ERR_ACCESS``: This flag enables/disables the SCR_EL3.TERR
782  bit, to trap access to the RAS ERR and RAS ERX registers from lower ELs.
783  This flag is disabled by default.
784
785- ``OPENSSL_DIR``: This flag is used to provide the installed openssl directory
786  path on the host machine which is used to build certificate generation and
787  firmware encryption tool.
788
789- ``USE_SP804_TIMER``: Use the SP804 timer instead of the Generic Timer for
790  functions that wait for an arbitrary time length (udelay and mdelay). The
791  default value is 0.
792
793- ``ENABLE_TRBE_FOR_NS``: This flag is used to enable access of trace buffer
794  control registers from NS ELs, NS-EL2 or NS-EL1(when NS-EL2 is implemented
795  but unused) when FEAT_TRBE is implemented. TRBE is an optional architectural
796  feature for AArch64. The default is 0 and it is automatically disabled when
797  the target architecture is AArch32.
798
799- ``ENABLE_SYS_REG_TRACE_FOR_NS``: Boolean option to enable trace system
800  registers access from NS ELs, NS-EL2 or NS-EL1 (when NS-EL2 is implemented
801  but unused). This feature is available if trace unit such as ETMv4.x, and
802  ETE(extending ETM feature) is implemented. This flag is disabled by default.
803
804- ``ENABLE_TRF_FOR_NS``: Boolean option to enable trace filter control registers
805  access from NS ELs, NS-EL2 or NS-EL1 (when NS-EL2 is implemented but unused),
806  if FEAT_TRF is implemented. This flag is disabled by default.
807
808GICv3 driver options
809--------------------
810
811GICv3 driver files are included using directive:
812
813``include drivers/arm/gic/v3/gicv3.mk``
814
815The driver can be configured with the following options set in the platform
816makefile:
817
818-  ``GICV3_SUPPORT_GIC600``: Add support for the GIC-600 variants of GICv3.
819   Enabling this option will add runtime detection support for the
820   GIC-600, so is safe to select even for a GIC500 implementation.
821   This option defaults to 0.
822
823- ``GICV3_SUPPORT_GIC600AE_FMU``: Add support for the Fault Management Unit
824   for GIC-600 AE. Enabling this option will introduce support to initialize
825   the FMU. Platforms should call the init function during boot to enable the
826   FMU and its safety mechanisms. This option defaults to 0.
827
828-  ``GICV3_IMPL_GIC600_MULTICHIP``: Selects GIC-600 variant with multichip
829   functionality. This option defaults to 0
830
831-  ``GICV3_OVERRIDE_DISTIF_PWR_OPS``: Allows override of default implementation
832   of ``arm_gicv3_distif_pre_save`` and ``arm_gicv3_distif_post_restore``
833   functions. This is required for FVP platform which need to simulate GIC save
834   and restore during SYSTEM_SUSPEND without powering down GIC. Default is 0.
835
836-  ``GIC_ENABLE_V4_EXTN`` : Enables GICv4 related changes in GICv3 driver.
837   This option defaults to 0.
838
839-  ``GIC_EXT_INTID``: When set to ``1``, GICv3 driver will support extended
840   PPI (1056-1119) and SPI (4096-5119) range. This option defaults to 0.
841
842Debugging options
843-----------------
844
845To compile a debug version and make the build more verbose use
846
847.. code:: shell
848
849    make PLAT=<platform> DEBUG=1 V=1 all
850
851AArch64 GCC uses DWARF version 4 debugging symbols by default. Some tools (for
852example DS-5) might not support this and may need an older version of DWARF
853symbols to be emitted by GCC. This can be achieved by using the
854``-gdwarf-<version>`` flag, with the version being set to 2 or 3. Setting the
855version to 2 is recommended for DS-5 versions older than 5.16.
856
857When debugging logic problems it might also be useful to disable all compiler
858optimizations by using ``-O0``.
859
860.. warning::
861   Using ``-O0`` could cause output images to be larger and base addresses
862   might need to be recalculated (see the **Memory layout on Arm development
863   platforms** section in the :ref:`Firmware Design`).
864
865Extra debug options can be passed to the build system by setting ``CFLAGS`` or
866``LDFLAGS``:
867
868.. code:: shell
869
870    CFLAGS='-O0 -gdwarf-2'                                     \
871    make PLAT=<platform> DEBUG=1 V=1 all
872
873Note that using ``-Wl,`` style compilation driver options in ``CFLAGS`` will be
874ignored as the linker is called directly.
875
876It is also possible to introduce an infinite loop to help in debugging the
877post-BL2 phase of TF-A. This can be done by rebuilding BL1 with the
878``SPIN_ON_BL1_EXIT=1`` build flag. Refer to the :ref:`build_options_common`
879section. In this case, the developer may take control of the target using a
880debugger when indicated by the console output. When using DS-5, the following
881commands can be used:
882
883::
884
885    # Stop target execution
886    interrupt
887
888    #
889    # Prepare your debugging environment, e.g. set breakpoints
890    #
891
892    # Jump over the debug loop
893    set var $AARCH64::$Core::$PC = $AARCH64::$Core::$PC + 4
894
895    # Resume execution
896    continue
897
898Firmware update options
899-----------------------
900
901-  ``NR_OF_FW_BANKS``: Define the number of firmware banks. This flag is used
902   in defining the firmware update metadata structure. This flag is by default
903   set to '2'.
904
905-  ``NR_OF_IMAGES_IN_FW_BANK``: Define the number of firmware images in each
906   firmware bank. Each firmware bank must have the same number of images as per
907   the `PSA FW update specification`_.
908   This flag is used in defining the firmware update metadata structure. This
909   flag is by default set to '1'.
910
911-  ``PSA_FWU_SUPPORT``: Enable the firmware update mechanism as per the
912   `PSA FW update specification`_. The default value is 0, and this is an
913   experimental feature.
914   PSA firmware update implementation has some limitations, such as BL2 is
915   not part of the protocol-updatable images, if BL2 needs to be updated, then
916   it should be done through another platform-defined mechanism, and it assumes
917   that the platform's hardware supports CRC32 instructions.
918
919--------------
920
921*Copyright (c) 2019-2021, Arm Limited. All rights reserved.*
922
923.. _DEN0115: https://developer.arm.com/docs/den0115/latest
924.. _PSA FW update specification: https://developer.arm.com/documentation/den0118/a/
925