System Control
ARM DDI 0500D
Copyright © 2013-2014 ARM. All rights reserved.
4-123
ID021414
Non-Confidential
Figure 4-69 RMR_EL3 bit assignments
Table 4-113
shows the RMR_EL3 bit assignments.
To access the RMR_EL3:
MRS <Xt>, RMR_EL3 ; Read RMR_EL3 into Xt
MSR RMR_EL3, <Xt> ; Write Xt to RMR_EL3
4.3.77
Interrupt Status Register
The ISR_EL1 characteristics are:
Purpose
Shows whether an IRQ, FIQ, or external abort is pending. An indicated
pending abort might be a physical abort or a virtual abort.
Usage constraints
This register is accessible as follows:
Configurations
ISR_EL1 is architecturally mapped to AArch32 register ISR. See
Interrupt Status Register
on page 4-265
.
Attributes
ISR_EL1 is a 32-bit register.
Figure 4-70 on page 4-124
shows the ISR_EL1 bit assignments.
31
0
RES
0
1
2
AA64
RR
Table 4-113 RMR_EL3 bit assignments
Bits
Name
Function
[31:2]
-
Reserved,
RES
0.
[1]
RR
Reset Request. The possible values are:
0
This is the reset value.
1
Requests a warm reset. This bit is set to 0 by either a cold or warm reset.
The bit is strictly a request.
[0]
AA64
a
Determines which execution state the processor boots into after a warm reset. The possible values are:
0
AArch32 Execution state.
1
AArch64 Execution state.
The reset vector address on reset takes a choice between two values, depending on the value in the AA64 bit. This
ensures that even with reprogramming of the AA64 bit, it is not possible to change the reset vector to go to a
different location.
a. The cold reset value depends on the
AA64nAA32
signal.
EL0
EL1
(NS)
EL1
(S)
EL2
EL3
(SCR.NS = 1)
EL3
(SCR.NS = 0)
-
RO
RO
RO
RO
RO