SLUUDG7 December   2025 MSPM33C321A

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Overview of Security Functionality
    1. 1.1 Terminology
  5. 2Secure Execution Environment
    1. 2.1 TrustZone
      1. 2.1.1 Implementation Defined Attribution Unit
      2. 2.1.2 Security Attribution Unit
      3. 2.1.3 TrustZone software development
    2. 2.2 Memory Protection Unit
      1. 2.2.1 TrustZone and MPU
    3. 2.3 Global Security Controller
      1. 2.3.1 GSC Memory configuration
        1. 2.3.1.1 Security Exceptions through the GSC & SAU
        2. 2.3.1.2 Priviledge exceptions with GSC & MPU
  6. 3Security Modules
    1. 3.1 AES
      1. 3.1.1 AES Overview
      2. 3.1.2 AES Usage
        1. 3.1.2.1 Configuration
        2. 3.1.2.2 Setup
        3. 3.1.2.3 Operation
    2. 3.2 Keystore
      1. 3.2.1 Overview
      2. 3.2.2 Keystore Usage
        1. 3.2.2.1 Configuration
        2. 3.2.2.2 Setup
        3. 3.2.2.3 Operation
    3. 3.3 SHA2
      1. 3.3.1 SHA Introduction
        1. 3.3.1.1 SHA features
      2. 3.3.2 SHA Performance
      3. 3.3.3 SHA Usage
        1. 3.3.3.1 Configuration
        2. 3.3.3.2 Setup
        3. 3.3.3.3 Operation
    4. 3.4 PKA
      1. 3.4.1 PKA Introduction
        1. 3.4.1.1 PKA features
      2. 3.4.2 PKA Usage
        1. 3.4.2.1 Configuration
        2. 3.4.2.2 Setup
        3. 3.4.2.3 Operation
    5. 3.5 PQC
      1. 3.5.1 ML-DSA
        1. 3.5.1.1 ML-DSA Introduction
        2. 3.5.1.2 ML-DSA Usage
          1. 3.5.1.2.1 Configuration
          2. 3.5.1.2.2 Setup
          3. 3.5.1.2.3 Operation
  7. 4Revision History

2.3.1.1 Security Exceptions through the GSC & SAU

Both the GSC and SAU have capabilities to attribute regions of memory with security. One major difference between the two is the GSC will generate a secure NMI while the SAU generates a secure fault. A secure NMI is handled through the error aggregation module (EAM) which allows the programmer to see specific details about the error. Such as which peripheral caused the error and address the error occurred. The GSC also isn't limited to 8 regions instead the flash, SRAM, and Peripheral have their own granularity for security attributes. For more specifics please see MSPM33C3-Series 160MHz Microcontrollers Technical Reference Manual.

For understanding which error occurs when using the GSC and SAU to attribute regions of memory as secure or non-secure please see table Table 2-2. An image showing this can also be seen in Security exceptions with the GSC and SAU

Table 2-1 Security interrupt based on GSC and SAU security Attributions
Processor State SAU + IDAU Security Attribution GSC Security Attribution Resulting Interrupt Access violation
Secure Secure Secure None None
Non-secure Secure Secure Security Fault Yes blocked by CPU
Secure Secure Non-secure None None
Non-secure Secure Non-secure Security Fault Yes blocked by CPU
Secure Non-secure Secure None None
Non-secure Non-secure Secure Security NMI Yes blocked by GSC
Secure Non-secure Non-secure None None
Non-secure Non-secure Non-secure None None

Security exceptions with the GSC and SAU