Microboot 1 and PSC-BL1#
After the BootROM has completed execution, PSC-ROM/PSC-BL1 releases reset on the BPMP R5 to start Microboot1 (MB1) in the boot flow process as follows:

MB1 extends BootROM to provide the same security level in conjunction with PSC-BL1. During MB1 sequence, these tasks are executed:
Set clock and security settings.
Initialize the platform configuration settings from MB1_BCT.
Initialize the SDRAM based on the MB1 boot configuration table, MB1_BCT, NVBCT, and MEM_BCT.
Initialize the CCPLEX.
Load/authenticate the iGPU-FW, BPMP-FW, PSC-FW and HPSE-PKG, SB-PKG firmwares.
Load the SC7 firmwares and prepare SC7 context.
Load/authenticate.
MB1_BCT
NVBCT
are NOT customer configurable.