Trusted Firmware M - v0.1

Trusted Firmware M provides a reference implementation of secure world software for ARMv8-M.

Note: The software implementation contained in this project is designed to be a reference implementation of the Arm Platform Security Architecture (PSA). It currently does not implement all the features of that architecture, however we expect the code to evolve over 2018 along with the specifications.

Terms 'TFM' and 'TF-M' are commonly used in documents and code and both refer to Trusted Firmware M.

Glossary has the list of terms and abbreviations.

License

The software is provided under a BSD-3-Clause License. Contributions to this project are accepted under the same license with developer sign-off as described in the Contributing Guidelines.

This project contains code from other projects as listed below. The code from external projects is limited to app and platform folders. The original license text is included in those source files.

• The platform folder currently contains drivers imported from external project and the files have Apache 2.0 license.
• The app folder contains files imported from CMSIS_5 project and the files have Apache 2.0 license.
• The bl2 folder contains files imported from MCUBoot project and the files have Apache 2.0 license.

Note Any code that has license other than BSD-3-Clause is kept in specific sub folders named ext so that it can isolated if required.

This Release

This release includes

• A Secure FW with support for PSA Level 1 isolation on ARMv8M.
• The Interfaces exposed by the Secure FW to NS side.
• A blocking secure fw model with NS application example.
• Example secure service (or secure function) running within this SPE.
  • Only secure storage service is supported in this release.
• Testcases running baremetal and with RTX to test the functionality.
• Basic support for higher level isolation but it is in progress with limited testing.
• BL2 bootloader for image authentication based on SHA256 and RSA-2048 digital signature.
• Build system based on cmake, supporting armclang and GNU Arm.

In progress

• Ongoing and incremental support for PSA features.
  • Level 3 PSA isolation
  • PSA Crypto API support
  • PSA IPC support
  • ...
• OS support and use case examples.
  • mbed OS upstream support
  • mbed cloud client examples
  • ...
• Additional platform support.
  • Musca test chip
  • Cortex M23 support
  • ...
• Ongoing security hardening, optimization and quality improvements.

Platforms

Current release has been tested on

• Cortex M33 based SSE-200 system -
  • FPGA image loaded on MPS2 board.
  • Fast model FVP_MPS2_AEMv8M.
  • Musca-A1 test chip board.
• Cortex M23 based IoT Kit system -
  • FPGA image loaded on MPS2 board.

Getting Started

Prerequisite

Trusted Firmware M provides a reference implementation of PSA specifications. It is assumed that the reader is familiar with PSA concepts and terms. PSA specifications are currently not available in the public domain.

The current TF-M implementation specifically targets TrustZone for ARMv8-M so a good understanding of the v8-M architecture is also necessary. A good place to get started with ARMv8-M is developer.arm.com.

Really getting started

Trusted Firmware M source code is available on trustedfirmware.org

To build & run TF-M

• Follow the SW requirements guide to set up your environment
• Follow the Build instructions to compile and build the TF-M source
• Follow the User guide for information on running the example

To port TF-M to a another system or OS, follow the OS Integration Guide

Please also see the glossary of terms used in the project.

Contributing Guidelines contains guidance on how to contribute to this project.

Further documents can be found in the docs folder.

Feedback and support

For this early access release, feedback is requested via email to [email protected] .

Version history

Version	Date	Description
0.1	2017-12-15	Early Access Release

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Copyright (c) 2017-2018, Arm Limited. All rights reserved.