Hard Processor System Remote System Update User Guide: Agilex™ 3 and Agilex™ 5 SoCs

ID 852610
Date 12/15/2025
Public
Document Table of Contents

5.2. Arm Trusted Firmware Support

The Arm Trusted Firmware (ATF) runs at the EL3, the highest execution level on Cortex* -A55 for Agilex™ 3 or Cortex* -A55/ Cortex* -A76 for Agilex™ 5. ATF is loaded as part of the boot process, and it remains resident.

ATF exports a Secure Monitor Call (SMC) handler which allows software running at lower execution levels to access services offered by the SDM such as FPGA configuration and RSU commands. Both U-Boot and Linux use the SMC handler.