Zynq UltraScale+ Device Technical Reference Manual (UG1085)

Document ID
Release Date
2.4 English

Table: System Protection Units Terminology summarizes the system protection units terminology.

Table 16-1:      System Protection Units Terminology




Allows and maintains isolation between the secure and non-secure processes within the same system.


System Memory Management Unit includes one translation cache unit (TCU) and six translation buffer units (TBU). Provides protection (and address translation) for all non-APU transactions targeting the PS address space. The protection functionality is applied to the physical address that occurs after the address translations. The SMMU registers are accessible only from the APU.


Xilinx Memory Protection Units (8 units). Provides memory partitioning and TrustZone protection for memory and FPD slaves.


Xilinx Peripheral Protection Unit (1 unit). Provides LPD peripheral isolation and IPI protection.


AXI Timeout Block. Prevents AXI masters from lockup if the slave does not respond within a programmed time. The ATB generates a response back to the master if the transaction times out. This term should not be confused with the CoreSight advanced trace bus (ATB) unit.


AXI Isolation Block. Provides functional isolating between the AXI master and the slave in preparation for an AXI master or slave to be powered down. The AIB is useful in a power management use case where, to save power, the FPD can be powered down when not needed.

Note:   In this chapter, the term secure implies the TrustZone classification. Secure is not meant to imply secure boot, encryption, or authentication.