13.3 IDAU Region Types
The IDAU region types are defined below:
| IDAU REGION TYPE | DESCRIPTION |
|---|---|
| INVALID | Regions that are not decoded by the Bus matrix. |
| SEC |
Secure region. Region which cannot be accessed by a Non-secure master. Non-secure transactions are discarded inside the CPU and a security fault is generated internally to the core. |
| NONSEC_W |
Non-secure region. Region which is accessible by a non-secure transaction. When a Secure transaction targets a Non-secure region, transaction type is changed to Non-secure. (_W means that the region implements a watermark register). |
| NSC_W |
Non-secure callable region. Region which allows Non-secure software to call a Secure function, the first instruction in the called Secure function must be a SG (Secure Gateway). (_W means that the region implements a watermark register). |
| EXEMPT_B |
Region exempt from attribution. The IDAU does not alter the transaction. |