Trusted Firmware v0.4 release documentation

Updates to readme.md and change-log.md to describe the features and changes in
the v0.4 release.

Change-Id: Ice0a7cf7abae349f552e662eac638a46acc5db3f

docs/change-log.md

+ARM Trusted Firmware - version 0.4
+==================================
+
+New features
+------------
+
+*   Makefile improvements:
+
+    *   Improved dependency checking when building.
+
+    *   Removed `dump` target (build now always produces dump files).
+
+    *   Enabled platform ports to optionally make use of parts of the Trusted
+        Firmware (e.g. BL3-1 only), rather than being forced to use all parts.
+        Also made the `fip` target optional.
+
+    *   Specified the full path to source files and removed use of the `vpath`
+        keyword.
+
+*   Provided translation table library code for potential re-use by platforms
+    other than the FVPs.
+
+*   Moved architectural timer setup to platform-specific code.
+
+*   Added standby state support to PSCI cpu_suspend implementation.
+
+*   SRAM usage improvements:
+
+    *   Started using the `-ffunction-sections`, `-fdata-sections` and
+        `--gc-sections` compiler/linker options to remove unused code and data
+        from the images. Previously, all common functions were being built into
+        all binary images, whether or not they were actually used.
+
+    *   Placed all assembler functions in their own section to allow more unused
+        functions to be removed from images.
+
+    *   Updated BL1 and BL2 to use a single coherent stack each, rather than one
+        per CPU.
+
+    *   Changed variables that were unnecessarily declared and initialized as
+        non-const (i.e. in the .data section) so they are either uninitialized
+        (zero init) or const.
+
+*   Moved the Test Secure-EL1 Payload (BL3-2) to execute in Trusted SRAM by
+    default. The option for it to run in Trusted DRAM remains.
+
+*   Implemented a TrustZone Address Space Controller (TZC-400) driver. A
+    default configuration is provided for the Base FVPs. This means the model
+    parameter `-C bp.secure_memory=1` is now supported.
+
+*   Started saving the PSCI cpu_suspend 'power_state' parameter prior to
+    suspending a CPU. This allows platforms that implement multiple power-down
+    states at the same affinity level to identify a specific state.
+
+*   Refactored the entire codebase to reduce the amount of nesting in header
+    files and to make the use of system/user includes more consistent. Also
+    split platform.h to separate out the platform porting declarations from the
+    required platform porting definitions and the definitions/declarations
+    specific to the platform port.
+
+*   Optimized the data cache clean/invalidate operations.
+
+*   Improved the BL3-1 unhandled exception handling and reporting. Unhandled
+    exceptions now result in a dump of registers to the console.
+
+*   Major rework to the handover interface between BL stages, in particular the
+    interface to BL3-1. The interface now conforms to a specification and is
+    more future proof.
+
+*   Added support for optionally making the BL3-1 entrypoint a reset handler
+    (instead of BL1). This allows platforms with an alternative image loading
+    architecture to re-use BL3-1 with fewer modifications to generic code.
+
+*   Reserved some DDR DRAM for secure use on FVP platforms to avoid future
+    compatibility problems with non-secure software.
+
+*   Added support for secure interrupts targeting the Secure-EL1 Payload (SP)
+    (using GICv2 routing only). Demonstrated this working by adding an interrupt
+    target and supporting test code to the TSP. Also demonstrated non-secure
+    interrupt handling during TSP processing.
+
+
+Issues resolved since last release
+----------------------------------
+
+*   Now support use of the model parameter `-C bp.secure_memory=1` in the Base
+    FVPs (see **New features**).
+
+*   Support for secure world interrupt handling now available (see **New
+    features**).
+
+*   Made enough SRAM savings (see **New features**) to enable the Test Secure-EL1
+    Payload (BL3-2) to execute in Trusted SRAM by default.
+
+*   The tested filesystem used for this release (Linaro AArch64 OpenEmbedded
+    14.04) now correctly reports progress in the console.
+
+*   Improved the Makefile structure to make it easier to separate out parts of
+    the Trusted Firmware for re-use in platform ports. Also, improved target
+    dependency checking.
+
+
+Known issues
+------------
+
+*   GICv3 support is experimental. The Linux kernel patches to support this are
+    not widely available. There are known issues with GICv3 initialization in
+    the ARM Trusted Firmware.
+
+*   Dynamic image loading is not available yet. The current image loader
+    implementation (used to load BL2 and all subsequent images) has some
+    limitations. Changing BL2 or BL3-1 load addresses in certain ways can lead
+    to loading errors, even if the images should theoretically fit in memory.
+
+*   The ARM Trusted Firmware still uses too much on-chip Trusted SRAM. A number
+    of RAM usage enhancements have been identified to rectify this situation.
+
+*   CPU idle does not work on the advertised version of the Foundation FVP.
+    Some FVP fixes are required that are not available externally at the time
+    of writing. This can be worked around by disabling CPU idle in the Linux
+    kernel.
+
+*   Various bugs in ARM Trusted Firmware, UEFI and the Linux kernel have been
+    observed when using Linaro toolchain versions later than 13.11. Although
+    most of these have been fixed, some remain at the time of writing. These
+    mainly seem to relate to a subtle change in the way the compiler converts
+    between 64-bit and 32-bit values (e.g. during casting operations), which
+    reveals previously hidden bugs in client code.
+
+*   The firmware design documentation for the Test Secure-EL1 Payload (TSP) and
+    its dispatcher (TSPD) is incomplete. Similarly for the PSCI section.
+
+
 ARM Trusted Firmware - version 0.3
 ==================================
 

readme.md

-ARM Trusted Firmware - version 0.3
+ARM Trusted Firmware - version 0.4
 ==================================
 
 ARM Trusted Firmware provides a reference implementation of secure world
@@ -11,14 +11,12 @@ Board Boot Requirements (TBBR) and [Secure Monitor] [TEE-SMC] code. As far as
 possible the code is designed for reuse or porting to other ARMv8-A model and
 hardware platforms.
 
-This release builds on the previous source code release, which has been
-available in source and binary form since the [Linaro AArch64 OpenEmbedded 13.11
-Engineering Build] [AArch64 LEB]. These support the Base FVP platform
-models from ARM.
+This release builds on previous source code releases, supporting the Base and
+Foundation FVP platform models from ARM.
 
 ARM will continue development in collaboration with interested parties to
 provide a full reference implementation of PSCI, TBBR and Secure Monitor code
-to the benefit of all developers working with ARMv8-A TrustZone software.
+to the benefit of all developers working with ARMv8-A TrustZone technology.
 
 
 License
@@ -32,9 +30,9 @@ source files.
 This Release
 ------------
 
-This release is an incomplete implementation of the Trusted Firmware. Only
-limited functionality is provided at present and it has not been optimized or
-subjected to extended robustness or stress testing.
+This release is a limited functionality implementation of the Trusted Firmware.
+It provides a suitable starting point for productization. Future versions will
+contain new features, optimizations and quality improvements.
 
 ### Functionality
 
@@ -60,14 +58,21 @@ subjected to extended robustness or stress testing.
     for the Secondary CPU Boot, CPU hotplug and CPU idle use-cases.
 
 *   A Test Secure-EL1 Payload and Dispatcher to demonstrate Secure Monitor
-    functionality such as world switching and EL1 context management. This
-    also demonstrates Secure-EL1 interaction with PSCI. Some of this
-    functionality is provided in library form for re-use by other Secure-EL1
-    Payload Dispatchers.
+    functionality such as world switching, EL1 context management and interrupt
+    routing. This also demonstrates Secure-EL1 interaction with PSCI. Some of
+    this functionality is provided in library form for re-use by other
+    Secure-EL1 Payload Dispatchers.
 
-For a full list of updated functionality and implementation details, please
-see the [User Guide]. The [Change Log] provides details of changes made
-since the last release.
+*   Support for alternative Trusted Boot Firmware. Some platforms have their own
+    Trusted Boot implementation and only require the Secure Monitor
+    functionality provided by ARM Trusted Firmware.
+
+*   Isolation of memory accessible by the secure world from the normal world
+    through programming of a TrustZone controller.
+
+For a full description of functionality and implementation details, please
+see the [Firmware Design] and supporting documentation. The [Change Log]
+provides details of changes made since the last release.
 
 ### Platforms
 
@@ -75,21 +80,23 @@ This release of the Trusted Firmware has been tested on the following ARM
 [FVP]s (64-bit versions only):
 
 *   `Foundation_v8` (Version 2.0, Build 0.8.5206)
-*   `FVP_Base_AEMv8A-AEMv8A` (Version 5.4, Build 0.8.5405)
-*   `FVP_Base_Cortex-A57x4-A53x4` (Version 5.4, Build 0.8.5405)
-*   `FVP_Base_Cortex-A57x1-A53x1` (Version 5.4, Build 0.8.5405)
+*   `FVP_Base_AEMv8A-AEMv8A` (Version 5.6, Build 0.8.5602)
+*   `FVP_Base_Cortex-A57x4-A53x4` (Version 5.6, Build 0.8.5602)
+*   `FVP_Base_Cortex-A57x1-A53x1` (Version 5.6, Build 0.8.5602)
+*   `FVP_Base_Cortex-A57x2-A53x4` (Version 5.6, Build 0.8.5602)
 
 The Foundation FVP can be downloaded free of charge. The Base FVPs can be
 licensed from ARM: see [www.arm.com/fvp] [FVP].
 
 ### Still to Come
 
-*   Complete implementation of the [PSCI] specification.
+*   Support for ARMv8-A development board as a reference platform.
 
-*   Secure memory, Secure interrupts and support for other types of Secure-EL1
-    Payloads.
+*   Complete Trusted Boot implementation.
+
+*   Complete implementation of the [PSCI] specification.
 
-*   Booting the firmware from a Virtio block device.
+*   Support for alternative types of Secure-EL1 Payloads.
 
 *   Completing the currently experimental GICv3 support.
 
@@ -112,7 +119,7 @@ See the [Porting Guide] as well for information about how to use this
 software on another ARMv8-A platform.
 
 See the [Contributing Guidelines] for information on how to contribute to this
-project and the [Acknowledgements] file for a list of contributors to the
+project and the [Acknowledgments] file for a list of contributors to the
 project.
 
 ### Feedback and support
@@ -130,7 +137,7 @@ _Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved._
 
 [License]:                  ./license.md "BSD license for ARM Trusted Firmware"
 [Contributing Guidelines]:  ./contributing.md "Guidelines for contributors"
-[Acknowledgements]:         ./acknowledgements.md "Contributor acknowledgements"
+[Acknowledgments]:          ./acknowledgements.md "Contributor acknowledgments"
 [Change Log]:               ./docs/change-log.md
 [User Guide]:               ./docs/user-guide.md
 [Firmware Design]:          ./docs/firmware-design.md
@@ -141,5 +148,4 @@ _Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved._
 [PSCI]:                  http://infocenter.arm.com/help/topic/com.arm.doc.den0022b/index.html "Power State Coordination Interface PDD (ARM DEN 0022B.b)"
 [SMCCC]:                 http://infocenter.arm.com/help/topic/com.arm.doc.den0028a/index.html "SMC Calling Convention PDD (ARM DEN 0028A)"
 [TEE-SMC]:               http://www.arm.com/products/processors/technologies/trustzone/tee-smc.php "Secure Monitor and TEEs"
-[AArch64 LEB]:           http://releases.linaro.org/13.11/openembedded/aarch64 "Linaro AArch64 OpenEmbedded ARM Fast Model 13.11 Release"
 [GitHub issue tracker]:  https://github.com/ARM-software/tf-issues/issues