| 摘要 |
<p>A data processing apparatus 2 has a memory attribute unit 7 having storage regions 9, such as secure domain 44 and less secure domain 46, for storing attribute data for controlling access to a corresponding memory address range by processing circuitry 4. In response to a target memory address, the processing circuitry 4 can perform a region identifying operation to output a region identifying value identifying which of the storage regions 9 of the attribute unit 7 corresponds to the target memory address. The region identifying value is made available to at least some software executed by the data processing apparatus 2. The target memory address can be supplied in a region identifying instruction which also specifies a general purpose register 8 into which the region identifying value is written thereby becoming available to software. This can be useful for quickly checking access permissions of a range of addresses or for determining how to update the memory attribute unit.</p> |
