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. 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. 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. 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_AMU_FCONF``: Enables configuration of the AMU through FCONF, which 228 allows platforms with auxiliary counters to describe them via the 229 ``HW_CONFIG`` device tree blob. Default is 0. 230 231- ``ENABLE_ASSERTIONS``: This option controls whether or not calls to ``assert()`` 232 are compiled out. For debug builds, this option defaults to 1, and calls to 233 ``assert()`` are left in place. For release builds, this option defaults to 0 234 and calls to ``assert()`` function are compiled out. This option can be set 235 independently of ``DEBUG``. It can also be used to hide any auxiliary code 236 that is only required for the assertion and does not fit in the assertion 237 itself. 238 239- ``ENABLE_BACKTRACE``: This option controls whether to enable backtrace 240 dumps or not. It is supported in both AArch64 and AArch32. However, in 241 AArch32 the format of the frame records are not defined in the AAPCS and they 242 are defined by the implementation. This implementation of backtrace only 243 supports the format used by GCC when T32 interworking is disabled. For this 244 reason enabling this option in AArch32 will force the compiler to only 245 generate A32 code. This option is enabled by default only in AArch64 debug 246 builds, but this behaviour can be overridden in each platform's Makefile or 247 in the build command line. 248 249- ``ENABLE_FEAT_HCX``: This option sets the bit SCR_EL3.HXEn in EL3 to allow 250 access to HCRX_EL2 (extended hypervisor control register) from EL2 as well as 251 adding HCRX_EL2 to the EL2 context save/restore operations. 252 253- ``ENABLE_LTO``: Boolean option to enable Link Time Optimization (LTO) 254 support in GCC for TF-A. This option is currently only supported for 255 AArch64. Default is 0. 256 257- ``ENABLE_MPAM_FOR_LOWER_ELS``: Boolean option to enable lower ELs to use MPAM 258 feature. MPAM is an optional Armv8.4 extension that enables various memory 259 system components and resources to define partitions; software running at 260 various ELs can assign themselves to desired partition to control their 261 performance aspects. 262 263 When this option is set to ``1``, EL3 allows lower ELs to access their own 264 MPAM registers without trapping into EL3. This option doesn't make use of 265 partitioning in EL3, however. Platform initialisation code should configure 266 and use partitions in EL3 as required. This option defaults to ``0``. 267 268- ``ENABLE_MPMM``: Boolean option to enable support for the Maximum Power 269 Mitigation Mechanism supported by certain Arm cores, which allows the SoC 270 firmware to detect and limit high activity events to assist in SoC processor 271 power domain dynamic power budgeting and limit the triggering of whole-rail 272 (i.e. clock chopping) responses to overcurrent conditions. Defaults to ``0``. 273 274- ``ENABLE_MPMM_FCONF``: Enables configuration of MPMM through FCONF, which 275 allows platforms with cores supporting MPMM to describe them via the 276 ``HW_CONFIG`` device tree blob. Default is 0. 277 278- ``ENABLE_PIE``: Boolean option to enable Position Independent Executable(PIE) 279 support within generic code in TF-A. This option is currently only supported 280 in BL2_AT_EL3, BL31, and BL32 (TSP) for AARCH64 binaries, and in BL32 281 (SP_min) for AARCH32. Default is 0. 282 283- ``ENABLE_PMF``: Boolean option to enable support for optional Performance 284 Measurement Framework(PMF). Default is 0. 285 286- ``ENABLE_PSCI_STAT``: Boolean option to enable support for optional PSCI 287 functions ``PSCI_STAT_RESIDENCY`` and ``PSCI_STAT_COUNT``. Default is 0. 288 In the absence of an alternate stat collection backend, ``ENABLE_PMF`` must 289 be enabled. If ``ENABLE_PMF`` is set, the residency statistics are tracked in 290 software. 291 292- ``ENABLE_RME``: Boolean option to enable support for the ARMv9 Realm 293 Management Extension. Default value is 0. This is currently an experimental 294 feature. 295 296- ``ENABLE_RUNTIME_INSTRUMENTATION``: Boolean option to enable runtime 297 instrumentation which injects timestamp collection points into TF-A to 298 allow runtime performance to be measured. Currently, only PSCI is 299 instrumented. Enabling this option enables the ``ENABLE_PMF`` build option 300 as well. Default is 0. 301 302- ``ENABLE_SME_FOR_NS``: Boolean option to enable Scalable Matrix Extension 303 (SME), SVE, and FPU/SIMD for the non-secure world only. These features share 304 registers so are enabled together. Using this option without 305 ENABLE_SME_FOR_SWD=1 will cause SME, SVE, and FPU/SIMD instructions in secure 306 world to trap to EL3. SME is an optional architectural feature for AArch64 307 and TF-A support is experimental. At this time, this build option cannot be 308 used on systems that have SPD=spmd/SPM_MM or ENABLE_RME, and attempting to 309 build with these options will fail. Default is 0. 310 311- ``ENABLE_SME_FOR_SWD``: Boolean option to enable the Scalable Matrix 312 Extension for secure world use along with SVE and FPU/SIMD, ENABLE_SME_FOR_NS 313 must also be set to use this. If enabling this, the secure world MUST 314 handle context switching for SME, SVE, and FPU/SIMD registers to ensure that 315 no data is leaked to non-secure world. This is experimental. Default is 0. 316 317- ``ENABLE_SPE_FOR_LOWER_ELS`` : Boolean option to enable Statistical Profiling 318 extensions. This is an optional architectural feature for AArch64. 319 The default is 1 but is automatically disabled when the target architecture 320 is AArch32. 321 322- ``ENABLE_SVE_FOR_NS``: Boolean option to enable Scalable Vector Extension 323 (SVE) for the Non-secure world only. SVE is an optional architectural feature 324 for AArch64. Note that when SVE is enabled for the Non-secure world, access 325 to SIMD and floating-point functionality from the Secure world is disabled by 326 default and controlled with ENABLE_SVE_FOR_SWD. 327 This is to avoid corruption of the Non-secure world data in the Z-registers 328 which are aliased by the SIMD and FP registers. The build option is not 329 compatible with the ``CTX_INCLUDE_FPREGS`` build option, and will raise an 330 assert on platforms where SVE is implemented and ``ENABLE_SVE_FOR_NS`` set to 331 1. The default is 1 but is automatically disabled when ENABLE_SME_FOR_NS=1 332 since SME encompasses SVE. At this time, this build option cannot be used on 333 systems that have SPM_MM enabled. 334 335- ``ENABLE_SVE_FOR_SWD``: Boolean option to enable SVE for the Secure world. 336 SVE is an optional architectural feature for AArch64. Note that this option 337 requires ENABLE_SVE_FOR_NS to be enabled. The default is 0 and it is 338 automatically disabled when the target architecture is AArch32. 339 340- ``ENABLE_STACK_PROTECTOR``: String option to enable the stack protection 341 checks in GCC. Allowed values are "all", "strong", "default" and "none". The 342 default value is set to "none". "strong" is the recommended stack protection 343 level if this feature is desired. "none" disables the stack protection. For 344 all values other than "none", the ``plat_get_stack_protector_canary()`` 345 platform hook needs to be implemented. The value is passed as the last 346 component of the option ``-fstack-protector-$ENABLE_STACK_PROTECTOR``. 347 348- ``ENCRYPT_BL31``: Binary flag to enable encryption of BL31 firmware. This 349 flag depends on ``DECRYPTION_SUPPORT`` build flag. 350 351- ``ENCRYPT_BL32``: Binary flag to enable encryption of Secure BL32 payload. 352 This flag depends on ``DECRYPTION_SUPPORT`` build flag. 353 354- ``ENC_KEY``: A 32-byte (256-bit) symmetric key in hex string format. It could 355 either be SSK or BSSK depending on ``FW_ENC_STATUS`` flag. This value depends 356 on ``DECRYPTION_SUPPORT`` build flag. 357 358- ``ENC_NONCE``: A 12-byte (96-bit) encryption nonce or Initialization Vector 359 (IV) in hex string format. This value depends on ``DECRYPTION_SUPPORT`` 360 build flag. 361 362- ``ERROR_DEPRECATED``: This option decides whether to treat the usage of 363 deprecated platform APIs, helper functions or drivers within Trusted 364 Firmware as error. It can take the value 1 (flag the use of deprecated 365 APIs as error) or 0. The default is 0. 366 367- ``EL3_EXCEPTION_HANDLING``: When set to ``1``, enable handling of exceptions 368 targeted at EL3. When set ``0`` (default), no exceptions are expected or 369 handled at EL3, and a panic will result. This is supported only for AArch64 370 builds. 371 372- ``EVENT_LOG_LEVEL``: Chooses the log level to use for Measured Boot when 373 ``MEASURED_BOOT`` is enabled. For a list of valid values, see ``LOG_LEVEL``. 374 Default value is 40 (LOG_LEVEL_INFO). 375 376- ``FAULT_INJECTION_SUPPORT``: ARMv8.4 extensions introduced support for fault 377 injection from lower ELs, and this build option enables lower ELs to use 378 Error Records accessed via System Registers to inject faults. This is 379 applicable only to AArch64 builds. 380 381 This feature is intended for testing purposes only, and is advisable to keep 382 disabled for production images. 383 384- ``FIP_NAME``: This is an optional build option which specifies the FIP 385 filename for the ``fip`` target. Default is ``fip.bin``. 386 387- ``FWU_FIP_NAME``: This is an optional build option which specifies the FWU 388 FIP filename for the ``fwu_fip`` target. Default is ``fwu_fip.bin``. 389 390- ``FW_ENC_STATUS``: Top level firmware's encryption numeric flag, values: 391 392 :: 393 394 0: Encryption is done with Secret Symmetric Key (SSK) which is common 395 for a class of devices. 396 1: Encryption is done with Binding Secret Symmetric Key (BSSK) which is 397 unique per device. 398 399 This flag depends on ``DECRYPTION_SUPPORT`` build flag. 400 401- ``GENERATE_COT``: Boolean flag used to build and execute the ``cert_create`` 402 tool to create certificates as per the Chain of Trust described in 403 :ref:`Trusted Board Boot`. The build system then calls ``fiptool`` to 404 include the certificates in the FIP and FWU_FIP. Default value is '0'. 405 406 Specify both ``TRUSTED_BOARD_BOOT=1`` and ``GENERATE_COT=1`` to include support 407 for the Trusted Board Boot feature in the BL1 and BL2 images, to generate 408 the corresponding certificates, and to include those certificates in the 409 FIP and FWU_FIP. 410 411 Note that if ``TRUSTED_BOARD_BOOT=0`` and ``GENERATE_COT=1``, the BL1 and BL2 412 images will not include support for Trusted Board Boot. The FIP will still 413 include the corresponding certificates. This FIP can be used to verify the 414 Chain of Trust on the host machine through other mechanisms. 415 416 Note that if ``TRUSTED_BOARD_BOOT=1`` and ``GENERATE_COT=0``, the BL1 and BL2 417 images will include support for Trusted Board Boot, but the FIP and FWU_FIP 418 will not include the corresponding certificates, causing a boot failure. 419 420- ``GICV2_G0_FOR_EL3``: Unlike GICv3, the GICv2 architecture doesn't have 421 inherent support for specific EL3 type interrupts. Setting this build option 422 to ``1`` assumes GICv2 *Group 0* interrupts are expected to target EL3, both 423 by :ref:`platform abstraction layer<platform Interrupt Controller API>` and 424 :ref:`Interrupt Management Framework<Interrupt Management Framework>`. 425 This allows GICv2 platforms to enable features requiring EL3 interrupt type. 426 This also means that all GICv2 Group 0 interrupts are delivered to EL3, and 427 the Secure Payload interrupts needs to be synchronously handed over to Secure 428 EL1 for handling. The default value of this option is ``0``, which means the 429 Group 0 interrupts are assumed to be handled by Secure EL1. 430 431- ``HANDLE_EA_EL3_FIRST``: When set to ``1``, External Aborts and SError 432 Interrupts will be always trapped in EL3 i.e. in BL31 at runtime. When set to 433 ``0`` (default), these exceptions will be trapped in the current exception 434 level (or in EL1 if the current exception level is EL0). 435 436- ``HW_ASSISTED_COHERENCY``: On most Arm systems to-date, platform-specific 437 software operations are required for CPUs to enter and exit coherency. 438 However, newer systems exist where CPUs' entry to and exit from coherency 439 is managed in hardware. Such systems require software to only initiate these 440 operations, and the rest is managed in hardware, minimizing active software 441 management. In such systems, this boolean option enables TF-A to carry out 442 build and run-time optimizations during boot and power management operations. 443 This option defaults to 0 and if it is enabled, then it implies 444 ``WARMBOOT_ENABLE_DCACHE_EARLY`` is also enabled. 445 446 If this flag is disabled while the platform which TF-A is compiled for 447 includes cores that manage coherency in hardware, then a compilation error is 448 generated. This is based on the fact that a system cannot have, at the same 449 time, cores that manage coherency in hardware and cores that don't. In other 450 words, a platform cannot have, at the same time, cores that require 451 ``HW_ASSISTED_COHERENCY=1`` and cores that require 452 ``HW_ASSISTED_COHERENCY=0``. 453 454 Note that, when ``HW_ASSISTED_COHERENCY`` is enabled, version 2 of 455 translation library (xlat tables v2) must be used; version 1 of translation 456 library is not supported. 457 458- ``INVERTED_MEMMAP``: memmap tool print by default lower addresses at the 459 bottom, higher addresses at the top. This build flag can be set to '1' to 460 invert this behavior. Lower addresses will be printed at the top and higher 461 addresses at the bottom. 462 463- ``JUNO_AARCH32_EL3_RUNTIME``: This build flag enables you to execute EL3 464 runtime software in AArch32 mode, which is required to run AArch32 on Juno. 465 By default this flag is set to '0'. Enabling this flag builds BL1 and BL2 in 466 AArch64 and facilitates the loading of ``SP_MIN`` and BL33 as AArch32 executable 467 images. 468 469- ``KEY_ALG``: This build flag enables the user to select the algorithm to be 470 used for generating the PKCS keys and subsequent signing of the certificate. 471 It accepts 3 values: ``rsa``, ``rsa_1_5`` and ``ecdsa``. The option 472 ``rsa_1_5`` is the legacy PKCS#1 RSA 1.5 algorithm which is not TBBR 473 compliant and is retained only for compatibility. The default value of this 474 flag is ``rsa`` which is the TBBR compliant PKCS#1 RSA 2.1 scheme. 475 476- ``KEY_SIZE``: This build flag enables the user to select the key size for 477 the algorithm specified by ``KEY_ALG``. The valid values for ``KEY_SIZE`` 478 depend on the chosen algorithm and the cryptographic module. 479 480 +-----------+------------------------------------+ 481 | KEY_ALG | Possible key sizes | 482 +===========+====================================+ 483 | rsa | 1024 , 2048 (default), 3072, 4096* | 484 +-----------+------------------------------------+ 485 | ecdsa | unavailable | 486 +-----------+------------------------------------+ 487 488 * Only 2048 bits size is available with CryptoCell 712 SBROM release 1. 489 Only 3072 bits size is available with CryptoCell 712 SBROM release 2. 490 491- ``HASH_ALG``: This build flag enables the user to select the secure hash 492 algorithm. It accepts 3 values: ``sha256``, ``sha384`` and ``sha512``. 493 The default value of this flag is ``sha256``. 494 495- ``LDFLAGS``: Extra user options appended to the linkers' command line in 496 addition to the one set by the build system. 497 498- ``LOG_LEVEL``: Chooses the log level, which controls the amount of console log 499 output compiled into the build. This should be one of the following: 500 501 :: 502 503 0 (LOG_LEVEL_NONE) 504 10 (LOG_LEVEL_ERROR) 505 20 (LOG_LEVEL_NOTICE) 506 30 (LOG_LEVEL_WARNING) 507 40 (LOG_LEVEL_INFO) 508 50 (LOG_LEVEL_VERBOSE) 509 510 All log output up to and including the selected log level is compiled into 511 the build. The default value is 40 in debug builds and 20 in release builds. 512 513- ``MEASURED_BOOT``: Boolean flag to include support for the Measured Boot 514 feature. If this flag is enabled ``TRUSTED_BOARD_BOOT`` must be set as well 515 in order to provide trust that the code taking the measurements and recording 516 them has not been tampered with. 517 518 This option defaults to 0. 519 520- ``NON_TRUSTED_WORLD_KEY``: This option is used when ``GENERATE_COT=1``. It 521 specifies the file that contains the Non-Trusted World private key in PEM 522 format. If ``SAVE_KEYS=1``, this file name will be used to save the key. 523 524- ``NS_BL2U``: Path to NS_BL2U image in the host file system. This image is 525 optional. It is only needed if the platform makefile specifies that it 526 is required in order to build the ``fwu_fip`` target. 527 528- ``NS_TIMER_SWITCH``: Enable save and restore for non-secure timer register 529 contents upon world switch. It can take either 0 (don't save and restore) or 530 1 (do save and restore). 0 is the default. An SPD may set this to 1 if it 531 wants the timer registers to be saved and restored. 532 533- ``OVERRIDE_LIBC``: This option allows platforms to override the default libc 534 for the BL image. It can be either 0 (include) or 1 (remove). The default 535 value is 0. 536 537- ``PL011_GENERIC_UART``: Boolean option to indicate the PL011 driver that 538 the underlying hardware is not a full PL011 UART but a minimally compliant 539 generic UART, which is a subset of the PL011. The driver will not access 540 any register that is not part of the SBSA generic UART specification. 541 Default value is 0 (a full PL011 compliant UART is present). 542 543- ``PLAT``: Choose a platform to build TF-A for. The chosen platform name 544 must be subdirectory of any depth under ``plat/``, and must contain a 545 platform makefile named ``platform.mk``. For example, to build TF-A for the 546 Arm Juno board, select PLAT=juno. 547 548- ``PRELOADED_BL33_BASE``: This option enables booting a preloaded BL33 image 549 instead of the normal boot flow. When defined, it must specify the entry 550 point address for the preloaded BL33 image. This option is incompatible with 551 ``EL3_PAYLOAD_BASE``. If both are defined, ``EL3_PAYLOAD_BASE`` has priority 552 over ``PRELOADED_BL33_BASE``. 553 554- ``PROGRAMMABLE_RESET_ADDRESS``: This option indicates whether the reset 555 vector address can be programmed or is fixed on the platform. It can take 556 either 0 (fixed) or 1 (programmable). Default is 0. If the platform has a 557 programmable reset address, it is expected that a CPU will start executing 558 code directly at the right address, both on a cold and warm reset. In this 559 case, there is no need to identify the entrypoint on boot and the boot path 560 can be optimised. The ``plat_get_my_entrypoint()`` platform porting interface 561 does not need to be implemented in this case. 562 563- ``PSCI_EXTENDED_STATE_ID``: As per PSCI1.0 Specification, there are 2 formats 564 possible for the PSCI power-state parameter: original and extended State-ID 565 formats. This flag if set to 1, configures the generic PSCI layer to use the 566 extended format. The default value of this flag is 0, which means by default 567 the original power-state format is used by the PSCI implementation. This flag 568 should be specified by the platform makefile and it governs the return value 569 of PSCI_FEATURES API for CPU_SUSPEND smc function id. When this option is 570 enabled on Arm platforms, the option ``ARM_RECOM_STATE_ID_ENC`` needs to be 571 set to 1 as well. 572 573- ``RAS_EXTENSION``: When set to ``1``, enable Armv8.2 RAS features. RAS features 574 are an optional extension for pre-Armv8.2 CPUs, but are mandatory for Armv8.2 575 or later CPUs. 576 577 When ``RAS_EXTENSION`` is set to ``1``, ``HANDLE_EA_EL3_FIRST`` must also be 578 set to ``1``. 579 580 This option is disabled by default. 581 582- ``RESET_TO_BL31``: Enable BL31 entrypoint as the CPU reset vector instead 583 of the BL1 entrypoint. It can take the value 0 (CPU reset to BL1 584 entrypoint) or 1 (CPU reset to BL31 entrypoint). 585 The default value is 0. 586 587- ``RESET_TO_SP_MIN``: SP_MIN is the minimal AArch32 Secure Payload provided 588 in TF-A. This flag configures SP_MIN entrypoint as the CPU reset vector 589 instead of the BL1 entrypoint. It can take the value 0 (CPU reset to BL1 590 entrypoint) or 1 (CPU reset to SP_MIN entrypoint). The default value is 0. 591 592- ``ROT_KEY``: This option is used when ``GENERATE_COT=1``. It specifies the 593 file that contains the ROT private key in PEM format and enforces public key 594 hash generation. If ``SAVE_KEYS=1``, this 595 file name will be used to save the key. 596 597- ``SAVE_KEYS``: This option is used when ``GENERATE_COT=1``. It tells the 598 certificate generation tool to save the keys used to establish the Chain of 599 Trust. Allowed options are '0' or '1'. Default is '0' (do not save). 600 601- ``SCP_BL2``: Path to SCP_BL2 image in the host file system. This image is optional. 602 If a SCP_BL2 image is present then this option must be passed for the ``fip`` 603 target. 604 605- ``SCP_BL2_KEY``: This option is used when ``GENERATE_COT=1``. It specifies the 606 file that contains the SCP_BL2 private key in PEM format. If ``SAVE_KEYS=1``, 607 this file name will be used to save the key. 608 609- ``SCP_BL2U``: Path to SCP_BL2U image in the host file system. This image is 610 optional. It is only needed if the platform makefile specifies that it 611 is required in order to build the ``fwu_fip`` target. 612 613- ``SDEI_SUPPORT``: Setting this to ``1`` enables support for Software 614 Delegated Exception Interface to BL31 image. This defaults to ``0``. 615 616 When set to ``1``, the build option ``EL3_EXCEPTION_HANDLING`` must also be 617 set to ``1``. 618 619- ``SEPARATE_CODE_AND_RODATA``: Whether code and read-only data should be 620 isolated on separate memory pages. This is a trade-off between security and 621 memory usage. See "Isolating code and read-only data on separate memory 622 pages" section in :ref:`Firmware Design`. This flag is disabled by default 623 and affects all BL images. 624 625- ``SEPARATE_NOBITS_REGION``: Setting this option to ``1`` allows the NOBITS 626 sections of BL31 (.bss, stacks, page tables, and coherent memory) to be 627 allocated in RAM discontiguous from the loaded firmware image. When set, the 628 platform is expected to provide definitions for ``BL31_NOBITS_BASE`` and 629 ``BL31_NOBITS_LIMIT``. When the option is ``0`` (the default), NOBITS 630 sections are placed in RAM immediately following the loaded firmware image. 631 632- ``SMC_PCI_SUPPORT``: This option allows platforms to handle PCI configuration 633 access requests via a standard SMCCC defined in `DEN0115`_. When combined with 634 UEFI+ACPI this can provide a certain amount of OS forward compatibility 635 with newer platforms that aren't ECAM compliant. 636 637- ``SPD``: Choose a Secure Payload Dispatcher component to be built into TF-A. 638 This build option is only valid if ``ARCH=aarch64``. The value should be 639 the path to the directory containing the SPD source, relative to 640 ``services/spd/``; the directory is expected to contain a makefile called 641 ``<spd-value>.mk``. The SPM Dispatcher standard service is located in 642 services/std_svc/spmd and enabled by ``SPD=spmd``. The SPM Dispatcher 643 cannot be enabled when the ``SPM_MM`` option is enabled. 644 645- ``SPIN_ON_BL1_EXIT``: This option introduces an infinite loop in BL1. It can 646 take either 0 (no loop) or 1 (add a loop). 0 is the default. This loop stops 647 execution in BL1 just before handing over to BL31. At this point, all 648 firmware images have been loaded in memory, and the MMU and caches are 649 turned off. Refer to the "Debugging options" section for more details. 650 651- ``SPMD_SPM_AT_SEL2`` : this boolean option is used jointly with the SPM 652 Dispatcher option (``SPD=spmd``). When enabled (1) it indicates the SPMC 653 component runs at the S-EL2 execution state provided by the Armv8.4-SecEL2 654 extension. This is the default when enabling the SPM Dispatcher. When 655 disabled (0) it indicates the SPMC component runs at the S-EL1 execution 656 state. This latter configuration supports pre-Armv8.4 platforms (aka not 657 implementing the Armv8.4-SecEL2 extension). 658 659- ``SPM_MM`` : Boolean option to enable the Management Mode (MM)-based Secure 660 Partition Manager (SPM) implementation. The default value is ``0`` 661 (disabled). This option cannot be enabled (``1``) when SPM Dispatcher is 662 enabled (``SPD=spmd``). 663 664- ``SP_LAYOUT_FILE``: Platform provided path to JSON file containing the 665 description of secure partitions. The build system will parse this file and 666 package all secure partition blobs into the FIP. This file is not 667 necessarily part of TF-A tree. Only available when ``SPD=spmd``. 668 669- ``SP_MIN_WITH_SECURE_FIQ``: Boolean flag to indicate the SP_MIN handles 670 secure interrupts (caught through the FIQ line). Platforms can enable 671 this directive if they need to handle such interruption. When enabled, 672 the FIQ are handled in monitor mode and non secure world is not allowed 673 to mask these events. Platforms that enable FIQ handling in SP_MIN shall 674 implement the api ``sp_min_plat_fiq_handler()``. The default value is 0. 675 676- ``TRUSTED_BOARD_BOOT``: Boolean flag to include support for the Trusted Board 677 Boot feature. When set to '1', BL1 and BL2 images include support to load 678 and verify the certificates and images in a FIP, and BL1 includes support 679 for the Firmware Update. The default value is '0'. Generation and inclusion 680 of certificates in the FIP and FWU_FIP depends upon the value of the 681 ``GENERATE_COT`` option. 682 683 .. warning:: 684 This option depends on ``CREATE_KEYS`` to be enabled. If the keys 685 already exist in disk, they will be overwritten without further notice. 686 687- ``TRUSTED_WORLD_KEY``: This option is used when ``GENERATE_COT=1``. It 688 specifies the file that contains the Trusted World private key in PEM 689 format. If ``SAVE_KEYS=1``, this file name will be used to save the key. 690 691- ``TSP_INIT_ASYNC``: Choose BL32 initialization method as asynchronous or 692 synchronous, (see "Initializing a BL32 Image" section in 693 :ref:`Firmware Design`). It can take the value 0 (BL32 is initialized using 694 synchronous method) or 1 (BL32 is initialized using asynchronous method). 695 Default is 0. 696 697- ``TSP_NS_INTR_ASYNC_PREEMPT``: A non zero value enables the interrupt 698 routing model which routes non-secure interrupts asynchronously from TSP 699 to EL3 causing immediate preemption of TSP. The EL3 is responsible 700 for saving and restoring the TSP context in this routing model. The 701 default routing model (when the value is 0) is to route non-secure 702 interrupts to TSP allowing it to save its context and hand over 703 synchronously to EL3 via an SMC. 704 705 .. note:: 706 When ``EL3_EXCEPTION_HANDLING`` is ``1``, ``TSP_NS_INTR_ASYNC_PREEMPT`` 707 must also be set to ``1``. 708 709- ``USE_ARM_LINK``: This flag determines whether to enable support for ARM 710 linker. When the ``LINKER`` build variable points to the armlink linker, 711 this flag is enabled automatically. To enable support for armlink, platforms 712 will have to provide a scatter file for the BL image. Currently, Tegra 713 platforms use the armlink support to compile BL3-1 images. 714 715- ``USE_COHERENT_MEM``: This flag determines whether to include the coherent 716 memory region in the BL memory map or not (see "Use of Coherent memory in 717 TF-A" section in :ref:`Firmware Design`). It can take the value 1 718 (Coherent memory region is included) or 0 (Coherent memory region is 719 excluded). Default is 1. 720 721- ``USE_DEBUGFS``: When set to 1 this option activates an EXPERIMENTAL feature 722 exposing a virtual filesystem interface through BL31 as a SiP SMC function. 723 Default is 0. 724 725- ``ARM_IO_IN_DTB``: This flag determines whether to use IO based on the 726 firmware configuration framework. This will move the io_policies into a 727 configuration device tree, instead of static structure in the code base. 728 729- ``COT_DESC_IN_DTB``: This flag determines whether to create COT descriptors 730 at runtime using fconf. If this flag is enabled, COT descriptors are 731 statically captured in tb_fw_config file in the form of device tree nodes 732 and properties. Currently, COT descriptors used by BL2 are moved to the 733 device tree and COT descriptors used by BL1 are retained in the code 734 base statically. 735 736- ``SDEI_IN_FCONF``: This flag determines whether to configure SDEI setup in 737 runtime using firmware configuration framework. The platform specific SDEI 738 shared and private events configuration is retrieved from device tree rather 739 than static C structures at compile time. This is only supported if 740 SDEI_SUPPORT build flag is enabled. 741 742- ``SEC_INT_DESC_IN_FCONF``: This flag determines whether to configure Group 0 743 and Group1 secure interrupts using the firmware configuration framework. The 744 platform specific secure interrupt property descriptor is retrieved from 745 device tree in runtime rather than depending on static C structure at compile 746 time. 747 748- ``USE_ROMLIB``: This flag determines whether library at ROM will be used. 749 This feature creates a library of functions to be placed in ROM and thus 750 reduces SRAM usage. Refer to :ref:`Library at ROM` for further details. Default 751 is 0. 752 753- ``V``: Verbose build. If assigned anything other than 0, the build commands 754 are printed. Default is 0. 755 756- ``VERSION_STRING``: String used in the log output for each TF-A image. 757 Defaults to a string formed by concatenating the version number, build type 758 and build string. 759 760- ``W``: Warning level. Some compiler warning options of interest have been 761 regrouped and put in the root Makefile. This flag can take the values 0 to 3, 762 each level enabling more warning options. Default is 0. 763 764- ``WARMBOOT_ENABLE_DCACHE_EARLY`` : Boolean option to enable D-cache early on 765 the CPU after warm boot. This is applicable for platforms which do not 766 require interconnect programming to enable cache coherency (eg: single 767 cluster platforms). If this option is enabled, then warm boot path 768 enables D-caches immediately after enabling MMU. This option defaults to 0. 769 770- ``SUPPORT_STACK_MEMTAG``: This flag determines whether to enable memory 771 tagging for stack or not. It accepts 2 values: ``yes`` and ``no``. The 772 default value of this flag is ``no``. Note this option must be enabled only 773 for ARM architecture greater than Armv8.5-A. 774 775- ``ERRATA_SPECULATIVE_AT``: This flag determines whether to enable ``AT`` 776 speculative errata workaround or not. It accepts 2 values: ``1`` and ``0``. 777 The default value of this flag is ``0``. 778 779 ``AT`` speculative errata workaround disables stage1 page table walk for 780 lower ELs (EL1 and EL0) in EL3 so that ``AT`` speculative fetch at any point 781 produces either the correct result or failure without TLB allocation. 782 783 This boolean option enables errata for all below CPUs. 784 785 +---------+--------------+-------------------------+ 786 | Errata | CPU | Workaround Define | 787 +=========+==============+=========================+ 788 | 1165522 | Cortex-A76 | ``ERRATA_A76_1165522`` | 789 +---------+--------------+-------------------------+ 790 | 1319367 | Cortex-A72 | ``ERRATA_A72_1319367`` | 791 +---------+--------------+-------------------------+ 792 | 1319537 | Cortex-A57 | ``ERRATA_A57_1319537`` | 793 +---------+--------------+-------------------------+ 794 | 1530923 | Cortex-A55 | ``ERRATA_A55_1530923`` | 795 +---------+--------------+-------------------------+ 796 | 1530924 | Cortex-A53 | ``ERRATA_A53_1530924`` | 797 +---------+--------------+-------------------------+ 798 799 .. note:: 800 This option is enabled by build only if platform sets any of above defines 801 mentioned in ’Workaround Define' column in the table. 802 If this option is enabled for the EL3 software then EL2 software also must 803 implement this workaround due to the behaviour of the errata mentioned 804 in new SDEN document which will get published soon. 805 806- ``RAS_TRAP_LOWER_EL_ERR_ACCESS``: This flag enables/disables the SCR_EL3.TERR 807 bit, to trap access to the RAS ERR and RAS ERX registers from lower ELs. 808 This flag is disabled by default. 809 810- ``OPENSSL_DIR``: This flag is used to provide the installed openssl directory 811 path on the host machine which is used to build certificate generation and 812 firmware encryption tool. 813 814- ``USE_SP804_TIMER``: Use the SP804 timer instead of the Generic Timer for 815 functions that wait for an arbitrary time length (udelay and mdelay). The 816 default value is 0. 817 818- ``ENABLE_TRBE_FOR_NS``: This flag is used to enable access of trace buffer 819 control registers from NS ELs, NS-EL2 or NS-EL1(when NS-EL2 is implemented 820 but unused) when FEAT_TRBE is implemented. TRBE is an optional architectural 821 feature for AArch64. The default is 0 and it is automatically disabled when 822 the target architecture is AArch32. 823 824- ``ENABLE_SYS_REG_TRACE_FOR_NS``: Boolean option to enable trace system 825 registers access from NS ELs, NS-EL2 or NS-EL1 (when NS-EL2 is implemented 826 but unused). This feature is available if trace unit such as ETMv4.x, and 827 ETE(extending ETM feature) is implemented. This flag is disabled by default. 828 829- ``ENABLE_TRF_FOR_NS``: Boolean option to enable trace filter control registers 830 access from NS ELs, NS-EL2 or NS-EL1 (when NS-EL2 is implemented but unused), 831 if FEAT_TRF is implemented. This flag is disabled by default. 832 833GICv3 driver options 834-------------------- 835 836GICv3 driver files are included using directive: 837 838``include drivers/arm/gic/v3/gicv3.mk`` 839 840The driver can be configured with the following options set in the platform 841makefile: 842 843- ``GICV3_SUPPORT_GIC600``: Add support for the GIC-600 variants of GICv3. 844 Enabling this option will add runtime detection support for the 845 GIC-600, so is safe to select even for a GIC500 implementation. 846 This option defaults to 0. 847 848- ``GICV3_SUPPORT_GIC600AE_FMU``: Add support for the Fault Management Unit 849 for GIC-600 AE. Enabling this option will introduce support to initialize 850 the FMU. Platforms should call the init function during boot to enable the 851 FMU and its safety mechanisms. This option defaults to 0. 852 853- ``GICV3_IMPL_GIC600_MULTICHIP``: Selects GIC-600 variant with multichip 854 functionality. This option defaults to 0 855 856- ``GICV3_OVERRIDE_DISTIF_PWR_OPS``: Allows override of default implementation 857 of ``arm_gicv3_distif_pre_save`` and ``arm_gicv3_distif_post_restore`` 858 functions. This is required for FVP platform which need to simulate GIC save 859 and restore during SYSTEM_SUSPEND without powering down GIC. Default is 0. 860 861- ``GIC_ENABLE_V4_EXTN`` : Enables GICv4 related changes in GICv3 driver. 862 This option defaults to 0. 863 864- ``GIC_EXT_INTID``: When set to ``1``, GICv3 driver will support extended 865 PPI (1056-1119) and SPI (4096-5119) range. This option defaults to 0. 866 867Debugging options 868----------------- 869 870To compile a debug version and make the build more verbose use 871 872.. code:: shell 873 874 make PLAT=<platform> DEBUG=1 V=1 all 875 876AArch64 GCC uses DWARF version 4 debugging symbols by default. Some tools (for 877example DS-5) might not support this and may need an older version of DWARF 878symbols to be emitted by GCC. This can be achieved by using the 879``-gdwarf-<version>`` flag, with the version being set to 2 or 3. Setting the 880version to 2 is recommended for DS-5 versions older than 5.16. 881 882When debugging logic problems it might also be useful to disable all compiler 883optimizations by using ``-O0``. 884 885.. warning:: 886 Using ``-O0`` could cause output images to be larger and base addresses 887 might need to be recalculated (see the **Memory layout on Arm development 888 platforms** section in the :ref:`Firmware Design`). 889 890Extra debug options can be passed to the build system by setting ``CFLAGS`` or 891``LDFLAGS``: 892 893.. code:: shell 894 895 CFLAGS='-O0 -gdwarf-2' \ 896 make PLAT=<platform> DEBUG=1 V=1 all 897 898Note that using ``-Wl,`` style compilation driver options in ``CFLAGS`` will be 899ignored as the linker is called directly. 900 901It is also possible to introduce an infinite loop to help in debugging the 902post-BL2 phase of TF-A. This can be done by rebuilding BL1 with the 903``SPIN_ON_BL1_EXIT=1`` build flag. Refer to the :ref:`build_options_common` 904section. In this case, the developer may take control of the target using a 905debugger when indicated by the console output. When using DS-5, the following 906commands can be used: 907 908:: 909 910 # Stop target execution 911 interrupt 912 913 # 914 # Prepare your debugging environment, e.g. set breakpoints 915 # 916 917 # Jump over the debug loop 918 set var $AARCH64::$Core::$PC = $AARCH64::$Core::$PC + 4 919 920 # Resume execution 921 continue 922 923Firmware update options 924----------------------- 925 926- ``NR_OF_FW_BANKS``: Define the number of firmware banks. This flag is used 927 in defining the firmware update metadata structure. This flag is by default 928 set to '2'. 929 930- ``NR_OF_IMAGES_IN_FW_BANK``: Define the number of firmware images in each 931 firmware bank. Each firmware bank must have the same number of images as per 932 the `PSA FW update specification`_. 933 This flag is used in defining the firmware update metadata structure. This 934 flag is by default set to '1'. 935 936- ``PSA_FWU_SUPPORT``: Enable the firmware update mechanism as per the 937 `PSA FW update specification`_. The default value is 0, and this is an 938 experimental feature. 939 PSA firmware update implementation has some limitations, such as BL2 is 940 not part of the protocol-updatable images, if BL2 needs to be updated, then 941 it should be done through another platform-defined mechanism, and it assumes 942 that the platform's hardware supports CRC32 instructions. 943 944-------------- 945 946*Copyright (c) 2019-2021, Arm Limited. All rights reserved.* 947 948.. _DEN0115: https://developer.arm.com/docs/den0115/latest 949.. _PSA FW update specification: https://developer.arm.com/documentation/den0118/a/ 950