14.3 Main Region Types
The Implementation Defined Attribution Unit bus system address map is strictly based on the system bus matrix address map. Each individual region decoded by the bus matrix is referred to as MAIN region further in this document. Each MAIN region is given a type.
The MAIN region type defines:
- The number of IDAU regions inside a MAIN region
- The type of each IDAU region inside a MAIN region
There is one valid region partition type:
- WATERMARK:MAIN region is divided by configuring the size of one or more watermarks (refer to Splittable Main Regions). Main region types using the watermark partition type are suffixed _W.
Splittable MAIN regions are split into several IDAU regions that each have a unique ID. In each water- mark partition-able MAIN region, at least one IDAU region has a watermark configuration. Such configurable IDAU regions are suffixed _W. MAIN region types that are not splittable do not have a underscore in their name.
| MAINREGION TYPE | DESCRIPTION | PARTITION TYPE |
|---|---|---|
| MR_INVALID | Single IDAU region of INVALID type | NONE |
| MR_SEC | Single IDAU region of SEC type | NONE |
| MR_NONSEC | Single IDAU region of NONSEC type | NONE |
| MR_SEC_NSC_W |
Contains two IDAU regions of type (lowest to highest addresses): SEC NSC_W(size is configurable with a watermark register) |
WATERMARK |
| MR_SEC_NSC_NONSEC_W |
Contains three IDAU regions of type (lowest to highest addresses): SEC NSC_W(size is configurable) NONSEC_W(size is configurable with a watermark register) |
WATERMARK |
| MR_SEC_NONSEC_W |
Contains two IDAU regions of type (lowest to highest addresses): SEC NONSEC_W(size is configurable with a watermark register) |
WATERMARK |
| MR_SECnNONSEC | Single IDAU region of SECnNONSEC_B type (either non-secure or secure).A SECnNONSEC_B IDAU region has a dedicated configuration register associated to it. | NONE |
| MR_SECnNONSEC_L | Single IDAU region of SECnNONSEC_L (either non-secure or secure).A SECnNONSEC_L IDAU region does not have a dedicated configuration register associated to it. It is using the configuration bit of another main region of MR_SECnNONSEC or MR_EXEMPT type. | NONE |
| MR_EXEMPT | Single IDAU region of EXEMPT_B type (exempt from security) | NONE |