Trusted Firmware-A

Reference Secure Firmware for Armv7-A, Armv8-A and Armv9-A systems


Trusted Firmware-A (TF-A) provides a reference implementation of secure world software for Armv7-A, Armv8-A and Armv9-A, including a Secure Monitor executing at Exception Level 3 (EL3) and a Secure Partition Manager running at Secure EL2 (S-EL2) of the Arm architecture.

Originally known as Arm Trusted Firmware, an Arm open source project since October 2013, with the recent launch of Trusted Firmware community project, TF-A has been migrated to an open governance model and it's now fully part of the Trusted Firmware community.

All the relevant content about TF-A can be found at these locations:

Trusted Firmware-A implements various Arm interface standards, such as:

  • Power State Coordination Interface (PSCI)
  • Trusted Board Boot Requirements (TBBR)
  • SMC Calling Convention  (SMCCC)
  • System Control and Management Interface (SCMI)
  • Software Delegated Exception Interface (SDEI)

Where possible, the code is designed for reuse or porting to other Armv7-A, Armv8-A and Armv9-A model and hardware platforms.

Trusted Firmware-A is provided as part of the Trusted Firmware community project under a BSD-3-Clause license and contributions are accepted under the term of Developer Certificate of Origin.

Latest News

Trusted Firmware-A v2.5 (TF-A, TF-A-Tests, Hafnium, TF-A CI) released through Open CI!

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Past News

Check out the past project news

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