System Control
ARM DDI 0500D
Copyright © 2013-2014 ARM. All rights reserved.
4-75
ID021414
Non-Confidential
Table 4-76
shows the SCTRLR_EL3 bit assignments.
Table 4-76 SCTLR_EL3 bit assignments
Bits
Name
Function
[31:30]
-
Reserved,
RES
0.
[29:28]
-
Reserved,
RES
1.
[27:26]
-
Reserved,
RES
0.
[25]
EE
Exception endianness. This bit controls the endianness for:
•
Explicit data accesses at EL3.
•
Stage 1 translation table walks at EL3.
The possible values are:
0
Little endian. This is the reset value.
1
Big endian.
[24]
-
Reserved,
RES
0.
[23:22]
-
Reserved,
RES
1.
[21:20]
-
Reserved,
RES
0.
[19]
WXN
Force treatment of all memory regions with write permissions as XN. The possible values are:
0
Regions with write permissions are not forced XN. This is the reset value.
1
Regions with write permissions are forced XN.
[18]
-
Reserved,
RES
1.
[17]
-
Reserved,
RES
0.
[16]
-
Reserved,
RES
1.
[15:13]
-
Reserved,
RES
0.
[12]
I
Global instruction cache enable. The possible values are:
0
Instruction caches disabled. This is the reset value.
1
Instruction caches enabled.
[11]
-
Reserved,
RES
1.
[10:6]
-
Reserved,
RES
0.
[5:4]
-
Reserved,
RES
1.
[3]
SA
Enables stack alignment check. The possible values are:
0
Disables stack alignment check.
1
Enables stack alignment check. This is the reset value.
[2]
C
Global enable for data and unifies caches. The possible values are:
0
Disables data and unified caches. This is the reset value.
1
Enables data and unified caches.
[1]
A
Enable alignment fault check The possible values are:
0
Disables alignment fault checking. This is the reset value.
1
Enables alignment fault checking.
[0]
M
Global enable for the EL3 MMU. The possible values are:
0
Disables EL3 MMU. This is the reset value.
1
Enables EL3 MMU.