doc: Move "About" content from index.rst to a new chapter

The index.rst page is now the primary landing page for the TF-A
documentation. It contains quite a lot of content these days,
including:

- The project purpose and general intro
- A list of functionality
- A list of planned functionality
- A list of supported platforms
- "Getting started" links to other documents
- Contact information for raising issues

This patch creates an "About" chapter in the table
of contents and moves some content there. In order,
the above listed content:

- Stayed where it is. This is the right place for it.
- Moved to About->Features
- Moved to About->Features (in subsection)
- Stayed where it is. Moved in a later patch.
- Was expanded in-place
- Moved to About->Contact

Change-Id: I254bb87560fd09140b9e485cf15246892aa45943
Signed-off-by: Paul Beesley <paul.beesley@arm.com>
diff --git a/docs/acknowledgements.rst b/docs/about/acknowledgements.rst
similarity index 87%
rename from docs/acknowledgements.rst
rename to docs/about/acknowledgements.rst
index 74b77ff..a9f6451 100644
--- a/docs/acknowledgements.rst
+++ b/docs/about/acknowledgements.rst
@@ -15,3 +15,7 @@
 - Socionext Inc.
 - STMicroelectronics
 - Xilinx, Inc.
+
+--------------
+
+*Copyright (c) 2019, Arm Limited. All rights reserved.*
diff --git a/docs/about/contact.rst b/docs/about/contact.rst
new file mode 100644
index 0000000..af6668d
--- /dev/null
+++ b/docs/about/contact.rst
@@ -0,0 +1,17 @@
+Support & Contact
+-----------------
+
+We welcome any feedback on TF-A. If you think you have found a security
+vulnerability, please report this using the process defined in the TF-A
+:ref:`Security Handling` document.
+
+For all other feedback, please use the `issue tracker`_ or our `mailing list`_.
+
+Arm licensees may contact Arm directly via their partner managers.
+
+.. _issue tracker: https://issues.trustedfirmware.org
+.. _mailing list: https://lists.trustedfirmware.org/mailman/listinfo/tf-a
+
+--------------
+
+*Copyright (c) 2019, Arm Limited. All rights reserved.*
diff --git a/docs/about/features.rst b/docs/about/features.rst
new file mode 100644
index 0000000..9df2894
--- /dev/null
+++ b/docs/about/features.rst
@@ -0,0 +1,127 @@
+Feature Overview
+================
+
+This page provides an overview of the current |TF-A| feature set. For a full
+description of these features and their implementation details, please see
+:ref:`Firmware Design` and supporting documentation.
+
+The :ref:`Change Log & Release Notes` provides details of changes made since the
+last release.
+
+Current features
+----------------
+
+-  Initialization of the secure world, for example exception vectors, control
+   registers and interrupts for the platform.
+
+-  Library support for CPU specific reset and power down sequences. This
+   includes support for errata workarounds and the latest Arm DynamIQ CPUs.
+
+-  Drivers to enable standard initialization of Arm System IP, for example
+   Generic Interrupt Controller (GIC), Cache Coherent Interconnect (CCI),
+   Cache Coherent Network (CCN), Network Interconnect (NIC) and TrustZone
+   Controller (TZC).
+
+-  A generic |SCMI| driver to interface with conforming power controllers, for
+   example the Arm System Control Processor (SCP).
+
+-  SMC (Secure Monitor Call) handling, conforming to the `SMC Calling
+   Convention`_ using an EL3 runtime services framework.
+
+-  |PSCI| library support for CPU, cluster and system power management
+   use-cases.
+   This library is pre-integrated with the AArch64 EL3 Runtime Software, and
+   is also suitable for integration with other AArch32 EL3 Runtime Software,
+   for example an AArch32 Secure OS.
+
+-  A minimal AArch32 Secure Payload (SP\_MIN) to demonstrate |PSCI| library
+   integration with AArch32 EL3 Runtime Software.
+
+-  Secure Monitor library code such as world switching, EL1 context management
+   and interrupt routing.
+   When a Secure-EL1 Payload (SP) is present, for example a Secure OS, the
+   AArch64 EL3 Runtime Software must be integrated with a Secure Payload
+   Dispatcher (SPD) component to customize the interaction with the SP.
+
+-  A Test SP and SPD to demonstrate AArch64 Secure Monitor functionality and SP
+   interaction with PSCI.
+
+-  SPDs for the `OP-TEE Secure OS`_, `NVIDIA Trusted Little Kernel`_
+   and `Trusty Secure OS`_.
+
+-  A Trusted Board Boot implementation, conforming to all mandatory TBBR
+   requirements. This includes image authentication, Firmware Update (or
+   recovery mode), and packaging of the various firmware images into a
+   Firmware Image Package (FIP).
+
+-  Pre-integration of TBB with the Arm CryptoCell product, to take advantage of
+   its hardware Root of Trust and crypto acceleration services.
+
+-  Reliability, Availability, and Serviceability (RAS) functionality, including
+
+   -  A Secure Partition Manager (SPM) to manage Secure Partitions in
+      Secure-EL0, which can be used to implement simple management and
+      security services.
+
+   -  An |SDEI| dispatcher to route interrupt-based |SDEI| events.
+
+   -  An Exception Handling Framework (EHF) that allows dispatching of EL3
+      interrupts to their registered handlers, to facilitate firmware-first
+      error handling.
+
+-  A dynamic configuration framework that enables each of the firmware images
+   to be configured at runtime if required by the platform. It also enables
+   loading of a hardware configuration (for example, a kernel device tree)
+   as part of the FIP, to be passed through the firmware stages.
+
+-  Support for alternative boot flows, for example to support platforms where
+   the EL3 Runtime Software is loaded using other firmware or a separate
+   secure system processor, or where a non-TF-A ROM expects BL2 to be loaded
+   at EL3.
+
+-  Support for the GCC, LLVM and Arm Compiler 6 toolchains.
+
+-  Support for combining several libraries into a "romlib" image that may be
+   shared across images to reduce memory footprint. The romlib image is stored
+   in ROM but is accessed through a jump-table that may be stored
+   in read-write memory, allowing for the library code to be patched.
+
+-  A prototype implementation of a Secure Partition Manager (SPM) that is based
+   on the SPCI Alpha 1 and SPRT draft specifications.
+
+-  Support for ARMv8.3 pointer authentication in the normal and secure worlds.
+   The use of pointer authentication in the normal world is enabled whenever
+   architectural support is available, without the need for additional build
+   flags. Use of pointer authentication in the secure world remains an
+   experimental configuration at this time and requires the
+   ``BRANCH_PROTECTION`` option to be set to non-zero.
+
+-  Position-Independent Executable (PIE) support. Initially for BL31 only, with
+   further support to be added in a future release.
+
+Still to come
+-------------
+
+-  Support for additional platforms.
+
+-  Refinements to Position Independent Executable (PIE) support.
+
+-  Refinements to the SPCI-based SPM implementation as the draft SPCI and SPRT
+   specifications continue to evolve.
+
+-  Documentation enhancements.
+
+-  Ongoing support for new architectural features, CPUs and System IP.
+
+-  Ongoing support for new Arm system architecture specifications.
+
+-  Ongoing security hardening, optimization and quality improvements.
+
+.. _SMC Calling Convention: http://infocenter.arm.com/help/topic/com.arm.doc.den0028b/ARM_DEN0028B_SMC_Calling_Convention.pdf
+.. _OP-TEE Secure OS: https://github.com/OP-TEE/optee_os
+.. _NVIDIA Trusted Little Kernel: http://nv-tegra.nvidia.com/gitweb/?p=3rdparty/ote_partner/tlk.git;a=summary
+.. _Trusty Secure OS: https://source.android.com/security/trusty
+
+--------------
+
+*Copyright (c) 2019, Arm Limited. All rights reserved.*
diff --git a/docs/about/index.rst b/docs/about/index.rst
new file mode 100644
index 0000000..3a10266
--- /dev/null
+++ b/docs/about/index.rst
@@ -0,0 +1,13 @@
+About
+=====
+
+.. toctree::
+   :maxdepth: 1
+   :caption: Contents
+   :numbered:
+
+   features
+   release-information
+   maintainers
+   contact
+   acknowledgements
diff --git a/docs/maintainers.rst b/docs/about/maintainers.rst
similarity index 100%
rename from docs/maintainers.rst
rename to docs/about/maintainers.rst
diff --git a/docs/process/release-information.rst b/docs/about/release-information.rst
similarity index 100%
rename from docs/process/release-information.rst
rename to docs/about/release-information.rst
diff --git a/docs/index.rst b/docs/index.rst
index 4cd1798..8981072 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -6,6 +6,7 @@
    :hidden:
 
    Home<self>
+   about/index
    getting_started/index
    process/index
    components/index
@@ -14,14 +15,9 @@
    perf/index
    security_advisories/index
    change-log
-   acknowledgements
    glossary
-   maintainers
    license
 
-.. contents:: On This Page
-    :depth: 3
-
 Trusted Firmware-A (TF-A) provides a reference implementation of secure world
 software for `Armv7-A and Armv8-A`_, including a `Secure Monitor`_ executing
 at Exception Level 3 (EL3). It implements various Arm interface standards,
@@ -47,101 +43,41 @@
 with reference implementations of Arm standards to benefit developers working
 with Armv7-A and Armv8-A TrustZone technology.
 
-Functionality
--------------
-
--  Initialization of the secure world, for example exception vectors, control
-   registers and interrupts for the platform.
-
--  Library support for CPU specific reset and power down sequences. This
-   includes support for errata workarounds and the latest Arm DynamIQ CPUs.
-
--  Drivers to enable standard initialization of Arm System IP, for example
-   Generic Interrupt Controller (GIC), Cache Coherent Interconnect (CCI),
-   Cache Coherent Network (CCN), Network Interconnect (NIC) and TrustZone
-   Controller (TZC).
-
--  A generic `SCMI`_ driver to interface with conforming power controllers, for
-   example the Arm System Control Processor (SCP).
-
--  SMC (Secure Monitor Call) handling, conforming to the `SMC Calling
-   Convention`_ using an EL3 runtime services framework.
-
--  `PSCI`_ library support for CPU, cluster and system power management
-   use-cases.
-   This library is pre-integrated with the AArch64 EL3 Runtime Software, and
-   is also suitable for integration with other AArch32 EL3 Runtime Software,
-   for example an AArch32 Secure OS.
-
--  A minimal AArch32 Secure Payload (SP\_MIN) to demonstrate `PSCI`_ library
-   integration with AArch32 EL3 Runtime Software.
-
--  Secure Monitor library code such as world switching, EL1 context management
-   and interrupt routing.
-   When a Secure-EL1 Payload (SP) is present, for example a Secure OS, the
-   AArch64 EL3 Runtime Software must be integrated with a Secure Payload
-   Dispatcher (SPD) component to customize the interaction with the SP.
-
--  A Test SP and SPD to demonstrate AArch64 Secure Monitor functionality and SP
-   interaction with PSCI.
-
--  SPDs for the `OP-TEE Secure OS`_, `NVIDIA Trusted Little Kernel`_
-   and `Trusty Secure OS`_.
-
--  A Trusted Board Boot implementation, conforming to all mandatory TBBR
-   requirements. This includes image authentication, Firmware Update (or
-   recovery mode), and packaging of the various firmware images into a
-   Firmware Image Package (FIP).
-
--  Pre-integration of TBB with the Arm CryptoCell product, to take advantage of
-   its hardware Root of Trust and crypto acceleration services.
-
--  Reliability, Availability, and Serviceability (RAS) functionality, including
-
-   -  A Secure Partition Manager (SPM) to manage Secure Partitions in
-      Secure-EL0, which can be used to implement simple management and
-      security services.
-
-   -  An |SDEI| dispatcher to route interrupt-based |SDEI| events.
+Getting Started
+---------------
 
-   -  An Exception Handling Framework (EHF) that allows dispatching of EL3
-      interrupts to their registered handlers, to facilitate firmware-first
-      error handling.
+The |TF-A| documentation contains guidance for obtaining and building the
+software for existing, supported platforms, as well as supporting information
+for porting the software to a new platform.
 
--  A dynamic configuration framework that enables each of the firmware images
-   to be configured at runtime if required by the platform. It also enables
-   loading of a hardware configuration (for example, a kernel device tree)
-   as part of the FIP, to be passed through the firmware stages.
+The **About** chapter gives a high-level overview of |TF-A| features as well as
+some information on the project and how it is organized.
 
--  Support for alternative boot flows, for example to support platforms where
-   the EL3 Runtime Software is loaded using other firmware or a separate
-   secure system processor, or where a non-TF-A ROM expects BL2 to be loaded
-   at EL3.
+Refer to the documents in the **Getting Started** chapter for information about
+the prerequisites and requirements for building |TF-A|.
 
--  Support for the GCC, LLVM and Arm Compiler 6 toolchains.
+The **Processes & Policies** chapter explains the project's release schedule
+and process, how security disclosures are handled, and the guidelines for
+contributing to the project (including the coding style).
 
--  Support for combining several libraries into a "romlib" image that may be
-   shared across images to reduce memory footprint. The romlib image is stored
-   in ROM but is accessed through a jump-table that may be stored
-   in read-write memory, allowing for the library code to be patched.
+The **Components** chapter holds documents that explain specific components
+that make up the |TF-A| software, the :ref:`Exception Handling Framework`, for
+example.
 
--  A prototype implementation of a Secure Partition Manager (SPM) that is based
-   on the SPCI Alpha 1 and SPRT draft specifications.
+In the **System Design** chapter you will find documents that explain the
+design of portions of the software that involve more than one component, such
+as the :ref:`Trusted Board Boot` process.
 
--  Support for ARMv8.3 pointer authentication in the normal and secure worlds.
-   The use of pointer authentication in the normal world is enabled whenever
-   architectural support is available, without the need for additional build
-   flags. Use of pointer authentication in the secure world remains an
-   experimental configuration at this time and requires the
-   ``BRANCH_PROTECTION`` option to be set to non-zero.
+**Platform Ports** provides a list of the supported hardware and software-model
+platforms that are supported upstream in |TF-A|. Most of these platforms also
+have additional documentation that has been provided by the maintainers of the
+platform.
 
--  Position-Independent Executable (PIE) support. Initially for BL31 only, with
-   further support to be added in a future release.
+The results of any performance evaluations are added to the
+**Performance & Testing** chapter.
 
-For a full description of functionality and implementation details, please
-see :ref:`Firmware Design` and supporting documentation. The
-:ref:`Change Log & Release Notes` provides details of changes made since the
-last release.
+**Security Advisories** holds a list of documents relating to |CVE| entries that
+have previously been raised against the software.
 
 Platforms
 ---------
@@ -224,74 +160,17 @@
 -  Texas Instruments K3 SoCs
 -  Xilinx Versal and Zynq UltraScale + MPSoC
 
-Still to come
--------------
-
--  Support for additional platforms.
-
--  Refinements to Position Independent Executable (PIE) support.
-
--  Refinements to the SPCI-based SPM implementation as the draft SPCI and SPRT
-   specifications continue to evolve.
-
--  Documentation enhancements.
-
--  Ongoing support for new architectural features, CPUs and System IP.
-
--  Ongoing support for new Arm system architecture specifications.
-
--  Ongoing security hardening, optimization and quality improvements.
-
-For a full list of detailed issues in the current code, please see the
-:ref:`Change Log & Release Notes` and the `issue tracker`_.
-
-Getting started
----------------
-
-See the :ref:`User Guide` for instructions on how to download, install, build
-and use TF-A with the Arm `FVP`_\ s.
-
-See the :ref:`Firmware Design` for information on how TF-A works.
-
-See the :ref:`Porting Guide` as well for information about how to use this
-software on another Armv7-A or Armv8-A platform.
-
-See the :ref:`Contributor's Guide` for information on how to contribute to this
-project and the :ref:`Contributor Acknowledgements` file for a list of
-contributors to the project.
-
-Contact Us
-~~~~~~~~~~
-
-We welcome any feedback on TF-A. If you think you have found a security
-vulnerability, please report this using the process defined in the TF-A
-:ref:`Security Handling` document.
-
-For all other feedback, please use the `issue tracker`_ or our `mailing list`_.
-
-Arm licensees may contact Arm directly via their partner managers.
-
 --------------
 
 *Copyright (c) 2013-2019, Arm Limited and Contributors. All rights reserved.*
 
 .. _Armv7-A and Armv8-A: https://developer.arm.com/products/architecture/a-profile
 .. _Secure Monitor: http://www.arm.com/products/processors/technologies/trustzone/tee-smc.php
-.. _Power State Coordination Interface (PSCI): PSCI_
-.. _PSCI: http://infocenter.arm.com/help/topic/com.arm.doc.den0022d/Power_State_Coordination_Interface_PDD_v1_1_DEN0022D.pdf
+.. _Power State Coordination Interface (PSCI): http://infocenter.arm.com/help/topic/com.arm.doc.den0022d/Power_State_Coordination_Interface_PDD_v1_1_DEN0022D.pdf
 .. _Trusted Board Boot Requirements CLIENT (TBBR-CLIENT): https://developer.arm.com/docs/den0006/latest/trusted-board-boot-requirements-client-tbbr-client-armv8-a
-.. _SMC Calling Convention: http://infocenter.arm.com/help/topic/com.arm.doc.den0028b/ARM_DEN0028B_SMC_Calling_Convention.pdf
-.. _System Control and Management Interface (SCMI): SCMI_
-.. _SCMI: http://infocenter.arm.com/help/topic/com.arm.doc.den0056a/DEN0056A_System_Control_and_Management_Interface.pdf
-.. _Software Delegated Exception Interface (SDEI): SDEI_
-.. _SDEI: http://infocenter.arm.com/help/topic/com.arm.doc.den0054a/ARM_DEN0054A_Software_Delegated_Exception_Interface.pdf
+.. _System Control and Management Interface (SCMI): http://infocenter.arm.com/help/topic/com.arm.doc.den0056a/DEN0056A_System_Control_and_Management_Interface.pdf
+.. _Software Delegated Exception Interface (SDEI): http://infocenter.arm.com/help/topic/com.arm.doc.den0054a/ARM_DEN0054A_Software_Delegated_Exception_Interface.pdf
 .. _Juno Arm Development Platform: http://www.arm.com/products/tools/development-boards/versatile-express/juno-arm-development-platform.php
-.. _Arm FVP website: FVP_
-.. _FVP: https://developer.arm.com/products/system-design/fixed-virtual-platforms
+.. _Arm FVP website: https://developer.arm.com/products/system-design/fixed-virtual-platforms
 .. _Linaro Release 19.06: http://releases.linaro.org/members/arm/platforms/19.06
-.. _OP-TEE Secure OS: https://github.com/OP-TEE/optee_os
-.. _NVIDIA Trusted Little Kernel: http://nv-tegra.nvidia.com/gitweb/?p=3rdparty/ote_partner/tlk.git;a=summary
-.. _Trusty Secure OS: https://source.android.com/security/trusty
-.. _trustedfirmware.org: https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git
-.. _issue tracker: https://issues.trustedfirmware.org
-.. _mailing list: https://lists.trustedfirmware.org/mailman/listinfo/tf-a
+.. _SMC Calling Convention: http://infocenter.arm.com/help/topic/com.arm.doc.den0028b/ARM_DEN0028B_SMC_Calling_Convention.pdf
diff --git a/docs/process/index.rst b/docs/process/index.rst
index a870c8f..9c12de8 100644
--- a/docs/process/index.rst
+++ b/docs/process/index.rst
@@ -6,7 +6,6 @@
    :caption: Contents
    :numbered:
 
-   release-information
    security
    platform-compatibility-policy
    coding-guidelines