infra/rde1edge: add user guide for rd-e1-edge platform

Add the initial user guide for the RD-E1-Edge platform software stack.
The user guide points to documents that provide information about
obtaining the platform software stack and using the various features it
supports. A table to list the release tags is included as well.

Signed-off-by: Thomas Abraham <thomas.abraham@arm.com>
Change-Id: I220490c4d3d1a60219ab012f07b7ac2ca23bc5f2

docs/infra/rde1edge/readme.rst

+RD-E1-Edge platform software user guide
+=======================================
+
+.. contents::
+
+
+Introduction
+------------
+
+RD (Reference Design) is a collection of resources to provide a representative
+view of typical compute subsystems that can be designed and implemented using
+specific generations of Arm IP. RD-E1-Edge in particular is based on the
+following hardware configuration.
+
+- 16x `Neoverse E1 Cores <https://developer.arm.com/products/processors/neoverse/neoverse-e1>`_
+   with DynamIQ Shared Unit (DSU).
+- Dedicated L2 cache: 256KB per core
+- Shared L3 cache: 2MB per cluster
+- CMN-600 with CML option: 8MB System Level Cache and 16MB Snoop Filter
+- DMC-620 with 2xRDIMM DDR4-3200
+- Multiple AXI expansion ports for I/O Coherent PCIe and Ethernet
+- Arm Cortex-M7 for System Control Processor (SCP) and
+  Manageability Control Processor (MCP)
+
+This document is a user guide on how to setup, build and run the RD-E1-Edge
+software stack on the Fixed Virtual Platform.
+
+
+Setting up the Host Machine and Syncing the software stack
+----------------------------------------------------------
+
+Host Machine requirements and the necessary steps to be followed to sync the
+software stack are listed on '`Download sources`_' page.
+
+
+Obtaining the RD-E1-Edge Fast Model
+-----------------------------------
+
+The latest version of RD-E1-Edge Fast Model can be requested by sending a email
+to Arm at this email address: `support-connect@arm.com <mailto:support-connect@arm.com>`_.
+
+Follow the instruction in the installer and setup the FVP. Typically, the
+installer will ask to create a new folder in the home directory. You can either
+install the FVP in the home folder, or in the ``fastmodel/refinfra`` folder
+inside the workspace. If you would like to install in the ``fastmodel/refinfra``
+folder, when asked for the install location, provide the absolute path of the
+``fastmodel/refinfra``.
+
+
+Supported Features
+------------------
+
+RD-E1-Edge platform software stack supports the following features.
+
+- `Busybox Boot`_.
+- `Buildroot Boot`_
+- `Linux Distribution Boot`_.
+- `UEFI Secure Boot`_
+
+Follow the links above for detailed information about the build and execute
+steps for each of the supported features.
+
+
+Release Tags
+------------
+
+Table below lists the release tags for the RD-N1-Edge platform software stack
+and the corresponding RD-V1 FVP version that is recommended to be used along
+with the listed release tag. The summary of the changes introduced and tests
+validated in each release is listed in `change log`_.
+
++-----------------------+--------------------------+
+|     Release Tag       |  RD-E1-Edge FVP Version  |
++=======================+==========================+
+|  RD-INFRA-2021.02.24  |         11.13.43         |
++-----------------------+--------------------------+
+
+
+--------------
+
+*Copyright (c) 2021, Arm Limited. All rights reserved.*
+
+
+.. _Busybox Boot: docs/infra/common/busybox-boot.rst
+.. _Buildroot Boot: docs/infra/common/buildroot-boot.rst
+.. _Linux Distribution Boot: docs/infra/common/distro-boot.rst
+.. _UEFI Secure Boot: docs/infra/common/secure-boot.rst
+.. _Download sources: docs/infra/common/download-sources.rst
+.. _change log: docs/infra/change-log.rst