B1.46 Cache Type Register
The CTR characteristics are:
Purpose
Provides information about the architecture of the caches.
Usage constraints
This register is accessible as follows:
EL0
(NS)
EL0
(S)
EL1
(NS)
EL1
(S)
EL2
EL3
(SCR.NS = 1)
EL3
(SCR.NS = 0)
- - RO RO RO RO RO
Configurations
CTR is architecturally mapped to AArch64 register CTR_EL0. See B2.35 Cache Type Register,
EL0 on page B2-410.
There is one copy of this register that is used in both Secure and Non-secure states.
Attributes
CTR is a 32-bit register.
IminLine
31 30 28 27 24 23 20 19 16 15 14 13 4 3 0
CWG ERG DminLine L1Ip RES0RES0
RES1
Figure B1-10 CTR bit assignments
[31]
Reserved, RES1.
[30:28]
Reserved, RES0.
CWG, [27:24]
Cache Write-Back granule. Log
2
of the number of words of the maximum size of memory that
can be overwritten as a result of the eviction of a cache entry that has had a memory location in
it modified:
0x4 Cache Write-Back granule size is 16 words.
ERG, [23:20]
Exclusives Reservation Granule. Log
2
of the number of words of the maximum size of the
reservation granule that has been implemented for the Load-Exclusive and Store-Exclusive
instructions:
0x4 Exclusive reservation granule size is 16 words.
DminLine, [19:16]
Log
2
of the number of words in the smallest cache line of all the data and unified caches that the
processor controls:
0x4 Smallest data cache line size is 16 words.
L1lp, [15:14]
B1 AArch32 system registers
B1.46 Cache Type Register
100236_0100_00_en Copyright © 2015–2017, 2019 Arm Limited or its affiliates. All rights
reserved.
B1-219
Non-Confidential