SPRUJ17H March 2022 – October 2024 AM2631 , AM2631-Q1 , AM2632 , AM2632-Q1 , AM2634 , AM2634-Q1
The secure boot flow is as depicted in Figure 5-4. The ROM-based secure boot is realized by interactions between the MSS R5F ROM and the HSM ROM. When the secondary bootloader (SBL) and the HSM runtime firmware is brought into the respective (MSS R5F and HSM CM4) cores, it is then the responsibility of the SBL to download the further application images. First, the ROM bootloader downloads the SBL. The SBL begins execution (MSS R5F ROM is eclipsed at this point and ROM services are not available anymore) and in turn invokes an API into HSM ROM to download the HSM runtime firmware. When the HSM runtime firmware is downloaded, the HSM ROM is eclipsed and ROM services not available anymore.