System Control
ARM DDI 0500D
Copyright © 2013-2014 ARM. All rights reserved.
4-172
ID021414
Non-Confidential
4.5.14
Instruction Set Attribute Register 0
The ID_ISAR0 characteristics are:
Purpose
Provides information about the instruction sets implemented by the
processor in AArch32.
Usage constraints
This register is accessible as follows:
Must be interpreted with ID_ISAR1, ID_ISAR2, ID_ISAR3, ID_ISAR4,
and ID_ISAR5. See:
•
Instruction Set Attribute Register 1
on page 4-173
.
•
Instruction Set Attribute Register 2
on page 4-175
.
•
Instruction Set Attribute Register 3
on page 4-178
.
•
Instruction Set Attribute Register 4
on page 4-179
.
•
Instruction Set Attribute Register 5
on page 4-181
.
Configurations
ID_ISAR0 is architecturally mapped to AArch64 register
ID_ISAR0_EL1. See
AArch32 Instruction Set Attribute Register 0
on
page 4-28
.
There is one copy of this register that is used in both Secure and
Non-secure states.
Attributes
ID_ISAR0 is a 32-bit register.
Figure 4-86
shows the ID_ISAR0 bit assignments.
Figure 4-86 ID_ISAR0 bit assignments
EL0
(NS)
EL0
(S)
EL1
(NS)
EL1
(S)
EL2
EL3
(SCR.NS = 1)
EL3
(SCR.NS = 0)
-
-
RO
RO
RO
RO
RO
31
28 27
24 23
20 19
16 15
12 11
8 7
4 3
0
RES
0
Divide
Debug
Coproc
CmpBranch
Bitfield
BitCount
Swap