Figure 1. Phase 2: Boot Setup
- The RCU begins to execute the BootROM from the RCU ROM.
- The BootROM reads the boot mode register to select the boot device.
- The BootROM reads the PDI boot header in the boot device and
- If the boot header is valid, the BootROM configures boot parameters based on the boot header data and then continues the boot process.
- If the boot header is not valid, then the normal boot process changes to the fallback boot process.
- The BootROM releases the reset to the PPU, and loads the PLM from the PDI into the PPU RAM and validates it. After validation, the PPU is woken up (at this point, the PLM software starts executing, refer to point 9 in Phase 3: Boot and Configuration sequence by PLM (Platform Loader).
- The BootROM executable enters a sleep state. The BootROM executable continues to run until the next power-on-reset (POR) or system reset, and is responsible for post-boot platform tasks.