[PATCH][platforms/devel-dynamictables] Branch to implement Dynamic Tables Framework

[Sami Mujawar <sami.mujawar@arm.com>]

This patch introduces a branch for implementing Dynamic Tables
Framework. The description is in the Readme.md file.

Please create a branch called 'devel-dynamictables' in edk2-platforms.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
Signed-off-by: Evan Lloyd <evan.lloyd@arm.com>
---
 Readme.md | 150 ++++++++++++++++++++
 1 file changed, 150 insertions(+)

diff --git a/Readme.md b/Readme.md
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+This branch will be used to develop the Configuration Manager,
+which is the platform specific component of the Dynamic Tables
+Framework.
+
+Dynamic Tables Framework
+------------------------
+
+To reduce the amount of effort required in porting firmware to new
+platforms, we propose this "Dynamic Tables" framework.  The aim is
+to provide an example implementation capable of generating the
+firmware tables from an external source.  This is potentially a
+management node, either local or remote, or, where suitable, a file
+that might be generated from the system construction.  This initial
+"proof of concept" release does not fully implement that - the
+configuration is held in local UEFI modules.
+
+Branch Owners
+-------------
+   Evan Lloyd <evan.lloyd@arm.com> \
+   Sami Mujawar <sami.mujawar@arm.com>
+
+Feature Summary
+---------------
+The dynamic tables framework is designed to generate standardised
+firmware tables that describe the hardware information at
+run-time. A goal of standardised firmware is to have a common
+firmware for a platform capable of booting both Windows and Linux
+operating systems.
+
+Traditionally the firmware tables are handcrafted using ACPI
+Source Language (ASL), Table Definition Language (TDL) and
+C-code. This approach can be error prone and involves time
+consuming debugging. In addition, it may be desirable to configure
+platform hardware at runtime such as: configuring the number of
+cores available for use by the OS, or turning SoC features ON or
+OFF.
+
+The dynamic tables framework simplifies this by providing a set
+of standard table generators, that are implemented as libraries.
+These generators query a platform specific component, the
+'Configuration Manager', to collate the information required
+for generating the tables at run-time.
+
+The framework also provides the ability to implement custom/OEM
+generators; thereby facilitating support for custom tables. The
+custom generators can also utilize the existing standard generators
+and override any functionality if needed.
+
+The framework currently implements a set of standard ACPI table
+generators for ARM architecture, that can generate Server Base Boot
+Requirement (SBBR) compliant tables. Although, the set of standard
+generators implement the functionality required for ARM architecture;
+the framework is extensible, and support for other architectures can
+be added easily.
+
+The framework currently supports the following table generators for ARM:
+* DBG2 - Debug Port Table 2
+* DSDT - Differentiated system description table. This is essentially
+         a RAW table generator.
+* FADT - Fixed ACPI Description Table
+* GTDT - Generic Timer Description Table
+* IORT - IO Remapping Table
+* MADT - Multiple APIC Description Table
+* MCFG - PCI Express memory mapped configuration space base address
+         Description Table
+* SPCR - Serial Port Console Redirection Table
+* SSDT - Secondary System Description Table. This is essentially
+         a RAW table generator.
+
+Roadmap
+-------
+The current implementation of the Configuration Manager populates the
+platform information statically as a C structure. Further enhancements
+to introduce runtime loading of platform information from a platform
+information file is planned.
+
+Also support for generating SMBIOS tables is planned and will be added
+subsequently.
+
+Related Modules
+---------------
+
+### edk2-staging
+The *dynamictables* branch in the **edk2-staging** repository
+contains the Dynamic Tables Framework.
+
+### ACPICA iASL compiler
+The RAW table generator, used to process the DSDT/SSDT files depends on
+the iASL compiler to convert the DSDT/SSDT ASL files to a C array containing
+the hex AML code. The current implementation of the iASL compiler does not
+support generation of a C header file suitable for including from a C source
+file.
+
+Related Links
+--------------
+
+<https://github.com/tianocore/edk2-staging.git>
+
+<https://github.com/acpica/acpica.git>
+
+
+Supported Platforms
+-------------------
+1. Juno
+2. FVP Models
+
+Build Instructions
+------------------
+1. Set path for the iASL compiler with support for generating a C header
+   file as output.
+
+2. Set PACKAGES_PATH to point to the locations of the following repositories:
+
+Example:
+
+> set PACKAGES_PATH=%CD%\edk2;%CD%\edk2-platforms;%CD%\edk2-non-osi
+
+  or
+
+> export PACKAGES_PATH=$PWD/edk2:$PWD/edk2-platforms:$PWD/edk2-non-osi
+
+3. To enable Dynamic tables framework the *'DYNAMIC_TABLES_FRAMEWORK'*
+option must be defined. This can be passed as a command line
+parameter to the edk2 build system.
+
+Example:
+
+>build -a AARCH64 -p Platform\ARM\JunoPkg\ArmJuno.dsc
+   -t GCC5 **-D DYNAMIC_TABLES_FRAMEWORK**
+
+or
+
+>build -a AARCH64 -p Platform\ARM\VExpressPkg\ArmVExpress-FVP-AArch64.dsc
+   -t GCC5 **-D DYNAMIC_TABLES_FRAMEWORK**
+
+Prerequisites
+-------------
+ACPICA iASL compiler with support for generating a C header file.
+
+A patch ***'Modify hex AML C header file generation'***, to enable
+this support has been submitted to the ACPICA source repository.
+<https://lists.acpica.org/pipermail/devel/2018-March/001755.html>
+
+Documentation
+-------------
+A description document is in preparation, and should be available in the
+near future.
+
+Miscellaneous
+-------------
-- 
'Guid(CE165669-3EF3-493F-B85D-6190EE5B9759)'