Reading from CP15 Register 3 returns the value of the Domain Access Control Register.

Writing to CP15 Register 3 writes the value of the Domain Access Control Register.

The Domain Access Control Register consists of 16 2-bit fields, each of which defines the access permissions for one of the 16 domains (D15-D0).

The CRm and opcode_2 fields Should Be Zero when reading or writing to CP15 Register 3. Domain Access Control Register format is shown in Figure 3.7.