System Control
ARM DDI 0500D
Copyright © 2013-2014 ARM. All rights reserved.
4-15
ID021414
Non-Confidential
To access the MIDR_EL1:
MRS <Xt>, MIDR_EL1 ; Read MIDR_EL1 into Xt
Table 4-14
shows the register access encoding:
The MIDR_EL1 can be accessed through the memory-mapped interface and the external debug
interface, offset
0xD00
.
4.3.2
Multiprocessor Affinity Register
The MPIDR_EL1 characteristics are:
Purpose
Provides an additional core identification mechanism for scheduling
purposes in a cluster system.
Usage constraints
This register is accessible as follows:
Configurations
The MPIDR_EL1[31:0] is:
•
Architecturally mapped to the AArch32 MPIDR register. See
Multiprocessor Affinity Register
on page 4-158
.
•
Mapped to external EDDEVAFF0 register.
MPIDR_EL1[63:32] is mapped to external EDDEVAFF1 register.
Attributes
MPIDR_EL1 is a 64-bit register.
Figure 4-2
shows the MPIDR_EL1 bit assignments.
Figure 4-2 MPIDR_EL1 bit assignments
Table 4-14 MIDR_EL1 access encoding
op0
op1
CRn
CRm
op2
11
000
0000
0000
000
EL0
EL1
(NS)
EL1
(S)
EL2
EL3
(SCR.NS = 1)
EL3
(SCR.NS = 0)
-
RO
RO
RO
RO
RO
Aff1
Aff0
0
63
16 15
8 7
Aff2
23
24
MT
RES
0
29
30
U
32 31
Aff3
40 39
RES
0
RES
1