System Control
ARM DDI 0500D
Copyright © 2013-2014 ARM. All rights reserved.
4-37
ID021414
Non-Confidential
Table 4-43
shows the ID_ISAR5_EL1 bit assignments.
To access the ID_ISAR5_EL1:
MRS <Xt>, ID_ISAR5_EL1 ; Read ID_ISAR5_EL1 into Xt
Register access is encoded as follows:
4.3.18
AArch64 Processor Feature Register 0
The ID_AA64PFR0_EL1 characteristics are:
Purpose
Provides additional information about implemented processor features in
AArch64.
Note
The optional Advanced SIMD and Floating-point extension is not
included in the base product of the processor. ARM requires licensees to
have contractual rights to obtain the Advanced SIMD and Floating-point
extension.
Usage constraints
This register is accessible as follows:
Table 4-43 ID_ISAR5_EL1 bit assignments
Bits
Name
Function
[31:20]
-
Reserved,
RES
0.
[19:16]
CRC32
Indicates whether CRC32 instructions are implemented in AArch32 state:
0x1
CRC32 instructions are implemented.
[15:12]
SHA2
Indicates whether SHA2 instructions are implemented in AArch32 state:
0x0
Cryptography Extensions are not implemented or are disabled.
0x1
SHA256H
,
SHA256H2
,
SHA256SU0
, and
SHA256SU1
instructions are implemented.
[11:8]
SHA1
Indicates whether SHA1 instructions are implemented in AArch32 state:
0x0
Cryptography Extensions are not implemented or are disabled.
0x1
SHA1C
,
SHA1P
,
SHA1M
,
SHA1H
,
SHA1SU0
, and
SHA1SU1
instructions are implemented.
[7:4]
AES
Indicates whether AES instructions are implemented in AArch32 state:
0x0
Cryptography Extensions are not implemented or are disabled.
0x2
AESE
,
AESD
,
AESMC
and
AESIMC
, plus
PMULL
and
PMULL2
instructions operating on 64-bit
data.
[3:0]
SEVL
Indicates whether the
SEVL
instruction is implemented:
0x1
SEVL
implemented to send event local.
Table 4-44 ID_ISAR5_EL1 access encoding
op0
op1
CRn
CRm
op2
11
000
0000
0010
101
EL0
EL1
(NS)
EL1
(S)
EL2
EL3
(SCR.NS = 1)
EL3
(SCR.NS = 0)
-
RO
RO
RO
RO
RO