Non-Secure Boot Flow - 2021.2 English

Versal ACAP System Software Developers Guide (UG1304)

Document ID
UG1304
Release Date
2021-10-27
Version
2021.2 English

The following figure illustrates an example boot and configuration sequence and shows how the PLM loads the major partition components of the Versal ACAP software stack.

Figure 1. Example Standard Boot Flow Processing Engines and Memory Sources

In non-secure boot mode, the BootROM loads the PLM into the PPU RAM and releases the PPU to begin PLM execution. The PLM continues loading of the images from the PDI. In the above boot flow example, the PLM initializes LPD, FPD and DDR memory through CDO files. As a part of LPD image, PLM loads and starts PSM Firmware. PLM loads PL CFI through RCDO file. PLM loads TF-A, U-Boot and starts TF-A (EL3-S) on APU. TF-A starts U-Boot (EL2-NS). U-Boot then loads Linux and hand-off to it. PLM can also load and start RPU and AI Engine images.

Note: In symmetric multi-processing (SMP) mode, the operating system manages the multiple Cortex-A72 processors.