Reading CP15 Register 6 returns the value of the Fault Address Register (FAR). The FAR holds the virtual address of the access that was attempted when a fault occurred. The FAR is only updated on data faults. There is no update on prefetch faults.

Writing to CP15 Register 6 sets the FAR to the value of the data written. This is useful when a debugger has to restore the value of the FAR.

The CRm and opcode_2 fields Should Be Zero when reading or writing CP15 Register 6. Fault Address Register format is shown in Figure 3.9.