1 2Realm Management Extension (RME) 3==================================== 4 5FEAT_RME (or RME for short) is an Armv9-A extension and is one component of the 6`Arm Confidential Compute Architecture (Arm CCA)`_. TF-A supports RME starting 7from version 2.6. This chapter discusses the changes to TF-A to support RME and 8provides instructions on how to build and run TF-A with RME. 9 10RME support in TF-A 11--------------------- 12 13The following diagram shows an Arm CCA software architecture with TF-A as the 14EL3 firmware. In the Arm CCA architecture there are two additional security 15states and address spaces: ``Root`` and ``Realm``. TF-A firmware runs in the 16Root world. In the realm world, a Realm Management Monitor firmware (`RMM`_) 17manages the execution of Realm VMs and their interaction with the hypervisor. 18 19.. image:: ../resources/diagrams/arm-cca-software-arch.png 20 21RME is the hardware extension to support Arm CCA. To support RME, various 22changes have been introduced to TF-A. We discuss those changes below. 23 24Changes to translation tables library 25*************************************** 26RME adds Root and Realm Physical address spaces. To support this, two new 27memory type macros, ``MT_ROOT`` and ``MT_REALM``, have been added to the 28:ref:`Translation (XLAT) Tables Library`. These macros are used to configure 29memory regions as Root or Realm respectively. 30 31.. note:: 32 33 Only version 2 of the translation tables library supports the new memory 34 types. 35 36Changes to context management 37******************************* 38A new CPU context for the Realm world has been added. The existing 39:ref:`CPU context management API<PSCI Library Integration guide for Armv8-A 40AArch32 systems>` can be used to manage Realm context. 41 42Boot flow changes 43******************* 44In a typical TF-A boot flow, BL2 runs at Secure-EL1. However when RME is 45enabled, TF-A runs in the Root world at EL3. Therefore, the boot flow is 46modified to run BL2 at EL3 when RME is enabled. In addition to this, a 47Realm-world firmware (`RMM`_) is loaded by BL2 in the Realm physical address 48space. 49 50The boot flow when RME is enabled looks like the following: 51 521. BL1 loads and executes BL2 at EL3 532. BL2 loads images including RMM 543. BL2 transfers control to BL31 554. BL31 initializes SPM (if SPM is enabled) 565. BL31 initializes RMM 576. BL31 transfers control to Normal-world software 58 59Granule Protection Tables (GPT) library 60***************************************** 61Isolation between the four physical address spaces is enforced by a process 62called Granule Protection Check (GPC) performed by the MMU downstream any 63address translation. GPC makes use of Granule Protection Table (GPT) in the 64Root world that describes the physical address space assignment of every 65page (granule). A GPT library that provides APIs to initialize GPTs and to 66transition granules between different physical address spaces has been added. 67More information about the GPT library can be found in the 68:ref:`Granule Protection Tables Library` chapter. 69 70RMM Dispatcher (RMMD) 71************************ 72RMMD is a new standard runtime service that handles the switch to the Realm 73world. It initializes the `RMM`_ and handles Realm Management Interface (RMI) 74SMC calls from Non-secure. 75 76There is a contract between `RMM`_ and RMMD that defines the arguments that the 77former needs to take in order to initialize and also the possible return values. 78This contract is defined in the `RMM`_ Boot Interface, which can be found at 79:ref:`rmm_el3_boot_interface`. 80 81There is also a specification of the runtime services provided by TF-A 82to `RMM`_. This can be found at :ref:`runtime_services_and_interface`. 83 84Test Realm Payload (TRP) 85************************* 86TRP is a small test payload that runs at R-EL2 and implements a subset of 87the Realm Management Interface (RMI) commands to primarily test EL3 firmware 88and the interface between R-EL2 and EL3. When building TF-A with RME enabled, 89if the path to an RMM image is not provided, TF-A builds the TRP by default 90and uses it as the R-EL2 payload. 91 92Building and running TF-A with RME 93---------------------------------- 94 95This section describes how you can build and run TF-A with RME enabled. 96We assume you have read the :ref:`Prerequisites` to build TF-A. 97 98The following instructions show you how to build and run TF-A with RME 99on FVP for two scenarios: 100 101- Three-world execution: This is the configuration to use if Secure 102 world functionality is not needed. TF-A is tested with the following 103 software entities in each world as listed below: 104 105 - NS Host (RME capable Linux or TF-A Tests), 106 - Root (TF-A) 107 - R-EL2 (`RMM`_ or TRP) 108 109- Four-world execution: This is the configuration to use if both Secure 110 and Realm world functionality is needed. TF-A is tested with the following 111 software entities in each world as listed below: 112 113 - NS Host (RME capable Linux or TF-A Tests), 114 - Root (TF-A) 115 - R-EL2 (`RMM`_ or TRP) 116 - S-EL2 (Hafnium SPM) 117 118To run the tests, you need an FVP model. Please use the :ref:`latest version 119<Arm Fixed Virtual Platforms (FVP)>` of *FVP_Base_RevC-2xAEMvA* model. If NS 120Host is Linux, then the below instructions assume that a suitable RME enabled 121kernel image and associated root filesystem are available. 122 123Three-world execution 124********************* 125 126**1. Clone and build RMM Image** 127 128Please refer to the `RMM Getting Started`_ on how to setup 129Host Environment and build `RMM`_. The build commands assume that 130an AArch64 toolchain and CMake executable are available in the 131shell PATH variable and CROSS_COMPILE variable has been setup 132appropriately. 133 134To clone `RMM`_ and build using the default build options for FVP: 135 136.. code:: shell 137 138 git clone --recursive https://git.trustedfirmware.org/TF-RMM/tf-rmm.git 139 cd tf-rmm 140 cmake -DRMM_CONFIG=fvp_defcfg -S . -B build 141 cmake --build build 142 143This will generate **rmm.img** in **build/Release** folder. 144 145**2. Clone and build TF-A Tests with Realm Payload** 146 147This step is only needed if NS Host is TF-A Tests. The full set 148of instructions to setup build host and build options for 149TF-A-Tests can be found in the `TFTF Getting Started`_. TF-A Tests 150can test Realm world with either `RMM`_ or TRP in R-EL2. In the TRP case, 151some tests which are not applicable will be skipped. 152 153Use the following instructions to build TF-A with `TF-A Tests`_ as the 154non-secure payload (BL33). 155 156.. code:: shell 157 158 git clone https://git.trustedfirmware.org/TF-A/tf-a-tests.git 159 cd tf-a-tests 160 make CROSS_COMPILE=aarch64-none-elf- PLAT=fvp DEBUG=1 all pack_realm 161 162This produces a TF-A Tests binary (**tftf.bin**) with Realm payload packaged 163and **sp_layout.json** in the **build/fvp/debug** directory. 164 165 166**3. Build RME Enabled TF-A** 167 168The `TF-A Getting Started`_ has the necessary instructions to setup Host 169machine and build TF-A. 170 171To build for RME, set ``ENABLE_RME`` build option to 1 and provide the path to 172the `RMM`_ binary ``rmm.img`` using ``RMM`` build option. 173 174.. note:: 175 176 ENABLE_RME build option is currently experimental. 177 178.. note:: 179 180 If the ``RMM`` option is not specified, TF-A builds the TRP to load and 181 run at R-EL2. 182 183.. code:: shell 184 185 git clone https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git 186 cd trusted-firmware-a 187 make CROSS_COMPILE=aarch64-none-elf- \ 188 PLAT=fvp \ 189 ENABLE_RME=1 \ 190 RMM=<path/to/rmm.img> \ 191 FVP_HW_CONFIG_DTS=fdts/fvp-base-gicv3-psci-1t.dts \ 192 DEBUG=1 \ 193 BL33=<path/to/bl33> \ 194 all fip 195 196``BL33`` can point to a Non Secure Bootloader like UEFI/U-Boot or 197the TF-A Tests binary(**tftf.bin**) from the previous step. 198 199This produces **bl1.bin** and **fip.bin** binaries in the **build/fvp/debug** 200directory. 201 202TF-A can also directly boot Linux kernel on the FVP. The kernel needs to be 203`preloaded` to a suitable memory location and this needs to be specified via 204``PRELOADED_BL33_BASE`` build option. Also TF-A should implement the Linux 205kernel register conventions for boot and this can be set using the 206``ARM_LINUX_KERNEL_AS_BL33`` option. 207 208.. code-block:: shell 209 210 cd trusted-firmware-a 211 make CROSS_COMPILE=aarch64-none-elf- \ 212 PLAT=fvp \ 213 ENABLE_RME=1 \ 214 RMM=<path/to/rmm.img> \ 215 FVP_HW_CONFIG_DTS=fdts/fvp-base-gicv3-psci-1t.dts \ 216 DEBUG=1 \ 217 ARM_LINUX_KERNEL_AS_BL33=1 \ 218 PRELOADED_BL33_BASE=0x84000000 \ 219 all fip 220 221The above command assumes that the Linux kernel will be placed in FVP 222memory at 0x84000000 via suitable FVP option (see the next step). 223 224.. _fvp_3_world_cmd: 225 226**4. Running FVP for 3 world setup** 227 228Use the following command to run the tests on FVP. 229 230.. code:: shell 231 232 FVP_Base_RevC-2xAEMvA \ 233 -C bp.refcounter.non_arch_start_at_default=1 \ 234 -C bp.secureflashloader.fname=<path/to/bl1.bin> \ 235 -C bp.flashloader0.fname=<path/to/fip.bin> \ 236 -C bp.refcounter.use_real_time=0 \ 237 -C bp.ve_sysregs.exit_on_shutdown=1 \ 238 -C cache_state_modelled=1 \ 239 -C bp.dram_size=4 \ 240 -C bp.secure_memory=1 \ 241 -C pci.pci_smmuv3.mmu.SMMU_ROOT_IDR0=3 \ 242 -C pci.pci_smmuv3.mmu.SMMU_ROOT_IIDR=0x43B \ 243 -C pci.pci_smmuv3.mmu.root_register_page_offset=0x20000 \ 244 -C cluster0.NUM_CORES=4 \ 245 -C cluster0.PA_SIZE=48 \ 246 -C cluster0.ecv_support_level=2 \ 247 -C cluster0.gicv3.cpuintf-mmap-access-level=2 \ 248 -C cluster0.gicv3.without-DS-support=1 \ 249 -C cluster0.gicv4.mask-virtual-interrupt=1 \ 250 -C cluster0.has_arm_v8-6=1 \ 251 -C cluster0.has_amu=1 \ 252 -C cluster0.has_branch_target_exception=1 \ 253 -C cluster0.rme_support_level=2 \ 254 -C cluster0.has_rndr=1 \ 255 -C cluster0.has_v8_7_pmu_extension=2 \ 256 -C cluster0.max_32bit_el=-1 \ 257 -C cluster0.stage12_tlb_size=1024 \ 258 -C cluster0.check_memory_attributes=0 \ 259 -C cluster0.ish_is_osh=1 \ 260 -C cluster0.restriction_on_speculative_execution=2 \ 261 -C cluster0.restriction_on_speculative_execution_aarch32=2 \ 262 -C cluster1.NUM_CORES=4 \ 263 -C cluster1.PA_SIZE=48 \ 264 -C cluster1.ecv_support_level=2 \ 265 -C cluster1.gicv3.cpuintf-mmap-access-level=2 \ 266 -C cluster1.gicv3.without-DS-support=1 \ 267 -C cluster1.gicv4.mask-virtual-interrupt=1 \ 268 -C cluster1.has_arm_v8-6=1 \ 269 -C cluster1.has_amu=1 \ 270 -C cluster1.has_branch_target_exception=1 \ 271 -C cluster1.rme_support_level=2 \ 272 -C cluster1.has_rndr=1 \ 273 -C cluster1.has_v8_7_pmu_extension=2 \ 274 -C cluster1.max_32bit_el=-1 \ 275 -C cluster1.stage12_tlb_size=1024 \ 276 -C cluster1.check_memory_attributes=0 \ 277 -C cluster1.ish_is_osh=1 \ 278 -C cluster1.restriction_on_speculative_execution=2 \ 279 -C cluster1.restriction_on_speculative_execution_aarch32=2 \ 280 -C pctl.startup=0.0.0.0 \ 281 -C bp.smsc_91c111.enabled=1 \ 282 -C bp.hostbridge.userNetworking=1 \ 283 -C bp.virtioblockdevice.image_path=<path/to/rootfs.ext4> 284 285The ``bp.virtioblockdevice.image_path`` option presents the rootfs as a 286virtio block device to Linux kernel. It can be ignored if NS Host is 287TF-A-Tests or rootfs is accessed by some other mechanism. 288 289If TF-A was built to expect a preloaded Linux kernel, then use the following 290FVP argument to load the kernel image at the expected address. 291 292.. code-block:: shell 293 294 --data cluster0.cpu0=<path_to_kernel_Image>@0x84000000 \ 295 296 297.. tip:: 298 Tips to boot and run Linux faster on the FVP : 299 1. Set the FVP option ``cache_state_modelled`` to 0. 300 2. Disable the CPU Idle driver in Linux either by setting the kernel command line 301 parameter "cpuidle.off=1" or by disabling the ``CONFIG_CPU_IDLE`` kernel config. 302 303If the NS Host is TF-A-Tests, then the default test suite in TFTF 304will execute on the FVP and this includes Realm world tests. The 305tail of the output from *uart0* should look something like the following. 306 307.. code-block:: shell 308 309 ... 310 311 > Test suite 'FF-A Interrupt' 312 Passed 313 > Test suite 'SMMUv3 tests' 314 Passed 315 > Test suite 'PMU Leakage' 316 Passed 317 > Test suite 'DebugFS' 318 Passed 319 > Test suite 'RMI and SPM tests' 320 Passed 321 > Test suite 'Realm payload at EL1' 322 Passed 323 > Test suite 'Invalid memory access' 324 Passed 325 ... 326 327Four-world execution 328******************** 329 330Four-world execution involves software components in each security state: root, 331secure, realm and non-secure. This section describes how to build TF-A 332with four-world support. 333 334We use TF-A as the root firmware, `Hafnium SPM`_ is the reference Secure world 335component running at S-EL2. `RMM`_ can be built as described in previous 336section. The examples below assume TF-A-Tests as the NS Host and utilize SPs 337from TF-A-Tests. 338 339**1. Obtain and build Hafnium SPM** 340 341.. code:: shell 342 343 git clone --recurse-submodules https://git.trustedfirmware.org/hafnium/hafnium.git 344 cd hafnium 345 # Use the default prebuilt LLVM/clang toolchain 346 PATH=$PWD/prebuilts/linux-x64/clang/bin:$PWD/prebuilts/linux-x64/dtc:$PATH 347 348Feature MTE needs to be disabled in Hafnium build, apply following patch to 349project/reference submodule 350 351.. code:: diff 352 353 diff --git a/BUILD.gn b/BUILD.gn 354 index cc6a78f..234b20a 100644 355 --- a/BUILD.gn 356 +++ b/BUILD.gn 357 @@ -83,7 +83,6 @@ aarch64_toolchains("secure_aem_v8a_fvp") { 358 pl011_base_address = "0x1c090000" 359 smmu_base_address = "0x2b400000" 360 smmu_memory_size = "0x100000" 361 - enable_mte = "1" 362 plat_log_level = "LOG_LEVEL_INFO" 363 } 364 } 365 366.. code:: shell 367 368 make PROJECT=reference 369 370The Hafnium binary should be located at 371*out/reference/secure_aem_v8a_fvp_clang/hafnium.bin* 372 373**2. Build RME enabled TF-A with SPM** 374 375Build TF-A with RME as well as SPM enabled. 376 377Use the ``sp_layout.json`` previously generated in TF-A Tests 378build to run SP tests. 379 380.. code:: shell 381 382 make CROSS_COMPILE=aarch64-none-elf- \ 383 PLAT=fvp \ 384 ENABLE_RME=1 \ 385 FVP_HW_CONFIG_DTS=fdts/fvp-base-gicv3-psci-1t.dts \ 386 SPD=spmd \ 387 BRANCH_PROTECTION=1 \ 388 CTX_INCLUDE_PAUTH_REGS=1 \ 389 DEBUG=1 \ 390 SP_LAYOUT_FILE=<path/to/sp_layout.json> \ 391 BL32=<path/to/hafnium.bin> \ 392 BL33=<path/to/tftf.bin> \ 393 RMM=<path/to/rmm.img> \ 394 all fip 395 396**3. Running the FVP for a 4 world setup** 397 398Use the following arguments in addition to the FVP options mentioned in 399:ref:`4. Running FVP for 3 world setup <fvp_3_world_cmd>` to run tests for 4004 world setup. 401 402.. code:: shell 403 404 -C pci.pci_smmuv3.mmu.SMMU_AIDR=2 \ 405 -C pci.pci_smmuv3.mmu.SMMU_IDR0=0x0046123B \ 406 -C pci.pci_smmuv3.mmu.SMMU_IDR1=0x00600002 \ 407 -C pci.pci_smmuv3.mmu.SMMU_IDR3=0x1714 \ 408 -C pci.pci_smmuv3.mmu.SMMU_IDR5=0xFFFF0475 \ 409 -C pci.pci_smmuv3.mmu.SMMU_S_IDR1=0xA0000002 \ 410 -C pci.pci_smmuv3.mmu.SMMU_S_IDR2=0 \ 411 -C pci.pci_smmuv3.mmu.SMMU_S_IDR3=0 412 413.. _Arm Confidential Compute Architecture (Arm CCA): https://www.arm.com/why-arm/architecture/security-features/arm-confidential-compute-architecture 414.. _Arm Architecture Models website: https://developer.arm.com/tools-and-software/simulation-models/fixed-virtual-platforms/arm-ecosystem-models 415.. _TF-A Getting Started: https://trustedfirmware-a.readthedocs.io/en/latest/getting_started/index.html 416.. _TF-A Tests: https://trustedfirmware-a-tests.readthedocs.io/en/latest 417.. _TFTF Getting Started: https://trustedfirmware-a-tests.readthedocs.io/en/latest/getting_started/index.html 418.. _Hafnium SPM: https://www.trustedfirmware.org/projects/hafnium 419.. _RMM Getting Started: https://tf-rmm.readthedocs.io/en/latest/getting_started/index.html 420.. _RMM: https://www.trustedfirmware.org/projects/tf-rmm/ 421