docs(rme): add build and run instructions for FEAT_RME

This patch adds instructions on how to build and run TF-A
with FEAT_RME enabled. The patch also adds code owners for
FEAT_RME.

Signed-off-by: Zelalem Aweke <zelalem.aweke@arm.com>
Change-Id: Id16dc52cb76b1ea56ac5c3fc38cb0794a62ac2a1
diff --git a/docs/about/maintainers.rst b/docs/about/maintainers.rst
index 1bd4666..7db81fc 100644
--- a/docs/about/maintainers.rst
+++ b/docs/about/maintainers.rst
@@ -109,6 +109,16 @@
 :|G|: `john-powell-arm`_
 :|F|: bl31/ehf.c
 
+Realm Management Extension (RME)
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+:|M|: Bipin Ravi <bipin.ravi@arm.com>
+:|G|: `bipinravi-arm`_
+:|M|: Mark Dykes <mark.dykes@arm.com>
+:|G|: `mardyk01`_
+:|M|: John Powell <John.Powell@arm.com>
+:|G|: `john-powell-arm`_
+:|M|: Zelalem Aweke <Zelalem.Aweke@arm.com>
+:|G|: `zelalem-aweke`_
 
 Drivers, Libraries and Framework Code
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/docs/components/index.rst b/docs/components/index.rst
index 2409f96..f349d8d 100644
--- a/docs/components/index.rst
+++ b/docs/components/index.rst
@@ -22,3 +22,4 @@
    ffa-manifest-binding
    xlat-tables-lib-v2-design
    cot-binding
+   realm-management-extension
diff --git a/docs/components/realm-management-extension.rst b/docs/components/realm-management-extension.rst
new file mode 100644
index 0000000..5c580f3
--- /dev/null
+++ b/docs/components/realm-management-extension.rst
@@ -0,0 +1,194 @@
+
+Realm Management Extension (RME)
+====================================
+
+FEAT_RME (or RME for short) is an Armv9-A extension and is one component of the
+`Arm Confidential Compute Architecture (Arm CCA)`_. TF-A supports RME starting
+from version 2.6. This document provides instructions on how to build and run
+TF-A with RME.
+
+Building and running TF-A with RME
+------------------------------------
+
+This section describes how you can build and run TF-A with RME enabled.
+We assume you have all the :ref:`Prerequisites` to build TF-A.
+
+To enable RME, you need to set the ENABLE_RME build flag when building
+TF-A. Currently, this feature is only supported for the FVP platform.
+
+The following instructions show you how to build and run TF-A with RME
+for two scenarios: TF-A with TF-A Tests, and four-world execution with
+Hafnium and TF-A Tests. The instructions assume you have already obtained
+TF-A. You can use the following command to clone TF-A.
+
+.. code:: shell
+
+ git clone https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git
+
+To run the tests, you need an FVP model. You can download a model that supports
+RME from the `Arm Architecture Models website`_. Please select the
+*Base RevC AEM FVP* model. After extracting the downloaded file, you should be able to
+find the *FVP_Base_RevC-2xAEMvA* binary. The instructions below have been tested
+with model version 11.15 revision 18.
+
+.. note::
+
+ ENABLE_RME build option is currently experimental.
+
+Building TF-A with TF-A Tests
+********************************************
+Use the following instructions to build TF-A with `TF-A Tests`_ as the
+non-secure payload (BL33).
+
+**1. Obtain and build TF-A Tests**
+
+.. code:: shell
+
+ git clone https://git.trustedfirmware.org/TF-A/tf-a-tests.git
+ cd tf-a-tests
+ make CROSS_COMPILE=aarch64-none-elf- PLAT=fvp DEBUG=1
+
+This produces a TF-A Tests binary (*tftf.bin*) in the *build/fvp/debug* directory.
+
+**2. Build TF-A**
+
+.. code:: shell
+
+ cd trusted-firmware-a
+ make CROSS_COMPILE=aarch64-none-elf- \
+ PLAT=fvp \
+ ENABLE_RME=1 \
+ FVP_HW_CONFIG_DTS=fdts/fvp-base-gicv3-psci-1t.dts \
+ DEBUG=1 \
+ BL33=<path/to/tftf.bin> \
+ all fip
+
+This produces *bl1.bin* and *fip.bin* binaries in the *build/fvp/debug* directory.
+The above command also builds a Test Realm Payload (TRP), which is a small test
+payload that implements Realm Monitor Management (RMM) functionalities and runs
+in the realm world (R-EL2). The TRP binary is packaged in *fip.bin*.
+
+Four-world execution with Hafnium and TF-A Tests
+****************************************************
+Four-world execution involves software components at each security state: root,
+secure, realm and non-secure. This section describes how to build TF-A
+with four-world support. We use TF-A as the root firmware, `Hafnium`_ as the
+secure component, TRP as the realm-world firmware and TF-A Tests as the
+non-secure payload.
+
+Before building TF-A, you first need to build the other software components.
+You can find instructions on how to get and build TF-A Tests above.
+
+**1. Obtain and build Hafnium**
+
+.. code:: shell
+
+ git clone --recurse-submodules https://git.trustedfirmware.org/hafnium/hafnium.git
+ cd hafnium
+ make PROJECT=reference
+
+The Hafnium binary should be located at
+*out/reference/secure_aem_v8a_fvp_clang/hafnium.bin*
+
+**2. Build TF-A**
+
+Build TF-A with RME as well as SPM enabled.
+
+.. code:: shell
+
+ make CROSS_COMPILE=aarch64-none-elf- \
+ PLAT=fvp \
+ ENABLE_RME=1 \
+ FVP_HW_CONFIG_DTS=fdts/fvp-base-gicv3-psci-1t.dts \
+ SPD=spmd \
+ SPMD_SPM_AT_SEL2=1 \
+ BRANCH_PROTECTION=1 \
+ CTX_INCLUDE_PAUTH_REGS=1 \
+ DEBUG=1 \
+ SP_LAYOUT_FILE=<path/to/tf-a-tests>/build/fvp/debug/sp_layout.json> \
+ BL32=<path/to/hafnium.bin> \
+ BL33=<path/to/tftf.bin> \
+ all fip
+
+Running the tests
+*********************
+Use the following command to run the tests on FVP. TF-A Tests should boot
+and run the default tests including RME tests.
+
+.. code:: shell
+
+ FVP_Base_RevC-2xAEMvA \
+ -C bp.flashloader0.fname=<path/to/fip.bin> \
+ -C bp.secureflashloader.fname=<path/to/bl1.bin> \
+ -C bp.refcounter.non_arch_start_at_default=1 \
+ -C bp.refcounter.use_real_time=0 \
+ -C bp.ve_sysregs.exit_on_shutdown=1 \
+ -C cache_state_modelled=1 \
+ -C cluster0.NUM_CORES=4 \
+ -C cluster0.PA_SIZE=48 \
+ -C cluster0.ecv_support_level=2 \
+ -C cluster0.gicv3.cpuintf-mmap-access-level=2 \
+ -C cluster0.gicv3.without-DS-support=1 \
+ -C cluster0.gicv4.mask-virtual-interrupt=1 \
+ -C cluster0.has_arm_v8-6=1 \
+ -C cluster0.has_branch_target_exception=1 \
+ -C cluster0.has_rme=1 \
+ -C cluster0.has_rndr=1 \
+ -C cluster0.has_amu=1 \
+ -C cluster0.has_v8_7_pmu_extension=2 \
+ -C cluster0.max_32bit_el=-1 \
+ -C cluster0.restriction_on_speculative_execution=2 \
+ -C cluster0.restriction_on_speculative_execution_aarch32=2 \
+ -C cluster1.NUM_CORES=4 \
+ -C cluster1.PA_SIZE=48 \
+ -C cluster1.ecv_support_level=2 \
+ -C cluster1.gicv3.cpuintf-mmap-access-level=2 \
+ -C cluster1.gicv3.without-DS-support=1 \
+ -C cluster1.gicv4.mask-virtual-interrupt=1 \
+ -C cluster1.has_arm_v8-6=1 \
+ -C cluster1.has_branch_target_exception=1 \
+ -C cluster1.has_rme=1 \
+ -C cluster1.has_rndr=1 \
+ -C cluster1.has_amu=1 \
+ -C cluster1.has_v8_7_pmu_extension=2 \
+ -C cluster1.max_32bit_el=-1 \
+ -C cluster1.restriction_on_speculative_execution=2 \
+ -C cluster1.restriction_on_speculative_execution_aarch32=2 \
+ -C pci.pci_smmuv3.mmu.SMMU_AIDR=2 \
+ -C pci.pci_smmuv3.mmu.SMMU_IDR0=0x0046123B \
+ -C pci.pci_smmuv3.mmu.SMMU_IDR1=0x00600002 \
+ -C pci.pci_smmuv3.mmu.SMMU_IDR3=0x1714 \
+ -C pci.pci_smmuv3.mmu.SMMU_IDR5=0xFFFF0475 \
+ -C pci.pci_smmuv3.mmu.SMMU_S_IDR1=0xA0000002 \
+ -C pci.pci_smmuv3.mmu.SMMU_S_IDR2=0 \
+ -C pci.pci_smmuv3.mmu.SMMU_S_IDR3=0 \
+ -C bp.pl011_uart0.out_file=uart0.log \
+ -C bp.pl011_uart1.out_file=uart1.log \
+ -C bp.pl011_uart2.out_file=uart2.log \
+ -C pctl.startup=0.0.0.0 \
+ -Q 1000 \
+ "$@"
+
+The bottom of the output from *uart0* should look something like the following.
+
+.. code-block:: shell
+
+ ...
+
+ > Test suite 'FF-A Interrupt'
+                                                                Passed
+ > Test suite 'SMMUv3 tests'
+                                                                Passed
+ > Test suite 'PMU Leakage'
+                                                                Passed
+ > Test suite 'DebugFS'
+                                                                Passed
+ > Test suite 'Realm payload tests'
+                                                                Passed
+ ...
+
+
+.. _Arm Confidential Compute Architecture (Arm CCA): https://www.arm.com/why-arm/architecture/security-features/arm-confidential-compute-architecture
+.. _Arm Architecture Models website: https://developer.arm.com/tools-and-software/simulation-models/fixed-virtual-platforms/arm-ecosystem-models
+.. _TF-A Tests: https://trustedfirmware-a-tests.readthedocs.io/en/latest
+.. _Hafnium: https://www.trustedfirmware.org/projects/hafnium