SWCU194 March 2023 CC1314R10 , CC1354P10 , CC1354R10 , CC2674P10 , CC2674R10
The Security Attribution Unit (SAU) determines the security of an address accessed by the processor. For instructions, the SAU returns the security attribute (Secure or Non-secure) and identifies whether the instruction address is in a Non-secure callable region.
For data, the SAU returns the security attribute (Secure or Non-secure). When a memory access is performed, the security of the address is verified by the SAU. Any address that matches multiple SAU regions is marked with the most secure attribute of the matching regions. There are 4 regions for which security can be defined.
The SAU is used with the IDAU and other security configuration settings to fully specify addresses as Secure, Non-secure, or Non-secure callable. See Section 2.4.7 for more information.