B2.24
CPUACTLR2_EL1, CPU Auxiliary Control Register 2, EL1
The CPUACTLR2_EL1 provides
IMPLEMENTATION DEFINED
configuration and control options for the core.
Bit field descriptions
CPUACTLR2_EL1 is a 64-bit register, and is part of the
IMPLEMENTATION DEFINED
registers functional
group.
0
Reserved
63
Figure B2-20 CPUACTLR2_EL1 bit assignments
Reserved, [63:0]
Reserved for Arm internal use.
Configurations
CPUACTLR2_EL1 is common to the Secure and Non-secure states.
Usage constraints
Accessing the CPUACTLR2_EL1
The CPUACTLR2_EL1 can be written only when the system is idle. Arm recommends that you
write to this register after a powerup reset, before the MMU is enabled.
Setting many of these bits can cause significantly lower performance on your code. Therefore,
Arm strongly recommends that you do not modify this register unless directed by Arm.
This register can be read using MRS with the following syntax:
MRS <Xt>,<systemreg>
This register can be written using MSR with the following syntax:
MSR <systemreg>, <Xt>
This syntax is encoded with the following settings in the instruction encoding:
<systemreg>
Op0 CRn Op1 CRm Op2
S3_0_C15_C1_1 3
c15
0
c1
1
Accessibility
This register is accessible in software as follows:
<syntax>
Control
Accessibility
E2H
TGE
NS
EL0
EL1
EL2
EL3
S3_0_C15_C1_1
x
x
0
-
RW
n/a
RW
S3_0_C15_C1_1
x
0
1
-
RW
RW
RW
S3_0_C15_C1_1
x
1
1
-
n/a
RW
RW
'n/a' Not accessible. The PE cannot be executing at this Exception level, so this access is not possible.
B2 AArch64 system registers
B2.24 CPUACTLR2_EL1, CPU Auxiliary Control Register 2, EL1
100798_0300_00_en
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B2-168
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Summary of Contents for Cortex-A76 Core
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