RSE Staged Boot

The default boot flow for RSE platform is mentioned in the doc RSE introduction

RSE can be easily adapted to various platform topologies. For example, in a platform with multiple RSE(s), (where each RSE resides on separate die loading different subsystems), not all the RSE(s) would have access to external flash for loading the images. In such scenarios, a staged boot is required. During the staged boot process, RSE with access to external flash would copy the entire GPT to the staged (local/common) RAM area. Then each RSE would parse the GPT/FIP from staged area and continue with normal boot flow.

To enable the staged boot by BL2, parameter RSE_BL2_ENABLE_IMAGE_STAGING must be enabled. The staging area addresses are defined the staging_config.h header file.