System Control
ARM DDI 0500D
Copyright © 2013-2014 ARM. All rights reserved.
4-164
ID021414
Non-Confidential
Attributes
ID_DFR0 is a 32-bit register.
Figure 4-81
shows the ID_DFR0 bit assignments.
Figure 4-81 ID_DFR0 bit assignments
Table 4-158
shows the ID_DFR0 bit assignments.
To access the ID_DFR0:
MRC p15,0,<Rt>,c0,c1,2 ; Read ID_DFR0 into Rt
Register access is encoded as follows:
4.5.9
Auxiliary Feature Register 0
This register is always
RES
0.
31
12 11
8 7
0
RES
0
4 3
24 23
20 19
16 15
28 27
PerfMon
MProfDbg
MMapTrc
CopTrc
CopSDbg
CopDbg
Reserved
Table 4-158 ID_DFR0 bit assignments
Bits
Name
Function
[31:28]
-
Reserved,
RES
0.
[27:24]
PerfMon
Indicates support for performance monitor model:
0x3
Support for
Performance Monitor Unit version 3
(PMUv3) system registers.
[23:20]
MProfDbg
Indicates support for memory-mapped debug model for M profile processors:
0x0
Processor does not support M profile Debug architecture.
[19:16]
MMapTrc
Indicates support for memory-mapped trace model:
0x1
Support for ARM trace architecture, with memory-mapped access.
In the Trace registers, the ETMIDR gives more information about the implementation.
[15:12]
CopTrc
Indicates support for coprocessor-based trace model:
0x0
Processor does not support ARM trace architecture, with CP14 access.
[11:8]
-
Reserved, RAZ.
[7:4]
CopSDbg
Indicates support for coprocessor-based Secure debug model:
0x6
Processor supports v8 Debug architecture, with CP14 access.
[3:0]
CopDbg
Indicates support for coprocessor-based debug model:
0x6
Processor supports v8 Debug architecture, with CP14 access.
Table 4-159 ID_DFR0 access encoding
coproc
opc1
CRn
CRm
opc2
1111
000
0000
0001
010