In this system protection use case, the RPU runs a safety application where a certain region of the OCM might be required to be protected and dedicated for use by the RPU. Some peripherals like the UART controller and the Quad-SPI controller could also require protection and be dedicated for use by the RPU. To accomplish these requirements the following is required:
•The RPU generates secure transactions.
•The XMPU protects the region of the OCM for the RPU and makes the rest available for use by other masters.
•The XPPU protects the UART controller and Quad-SPI controller for use by the RPU.
Similarly, to protect access to the PL through the PS PCAP interface, the XPPU can be programmed to protect the CSU subsystem and DMA register sets.