SPRY303F May   2019  – February 2025 AM3351 , AM3352 , AM3354 , AM3356 , AM3357 , AM3358 , AM3358-EP , AM3359 , AM4372 , AM4376 , AM4377 , AM4378 , AM4379 , AM5706 , AM5708 , AM5746 , AM5748 , AM623 , AM625 , AM625-Q1 , AM625SIP , AM62A1-Q1 , AM62A3 , AM62A3-Q1 , AM62A7 , AM62A7-Q1 , AM62L , AM62P , AM62P-Q1 , AM6411 , AM6412 , AM6421 , AM6422 , AM6441 , AM6442 , AM6526 , AM6528 , AM6546 , AM6548 , AM68 , AM68A , AM69 , AM69A , DRA821U , DRA821U-Q1 , DRA829J , DRA829J-Q1 , DRA829V , DRA829V-Q1 , TDA4VM , TDA4VM-Q1

 

  1.   1
  2.   Introduction
  3.   Risk management
  4.   What to protect?
  5.   How much security?
  6.   Architectural considerations
  7.   The security pyramid
  8.   Secure boot
  9.   Cryptographic acceleration
  10.   Device-ID and keys
  11.   Debug security
  12.   Trusted execution environment
  13.   External memory protection
  14.   Network security
  15.   Secure storage
  16.   Initial secure programming
  17.   Secure firmware and software updates
  18.   Software Intellectual Property (IP) protection
  19.   Physical security
  20.   Enclosure protection
  21.   Where to start with embedded security?
  22.   Security enablers for TI application processors
  23.   Conclusion
  24.   References

External memory protection

When designers must add another application or subsystem to the system, they usually are faced with adding memory that is external to the main processor and connected to it by a memory bus. Designers must protect the data stored in external memory against tampering or replacement so they can be ensured that only trusted data or application code are stored in external memory. A number of methods can be employed to safeguard the contents of external memory, such as secured execute-in-place directly from external memory without loading data into the processor’s integrated memory, decrypt-on-the-fly which can maintain confidentiality while allowing applications to run on the main processor and other methods.

Secure memory. Figure 5 Secure memory.