System Control
ARM DDI 0500D
Copyright © 2013-2014 ARM. All rights reserved.
4-189
ID021414
Non-Confidential
Figure 4-95 CTR bit assignments
Table 4-59 on page 4-47
shows the CTR bit assignments.
To access the CTR:
MRC p15,0,<Rt>,c0,c0,1 ; Read CTR into Rt
Register access is encoded as follows:
4.5.25
Virtualization Processor ID Register
The VPIDR characteristics are:
Purpose
Holds the value of the Virtualization Processor ID. This is the value
returned by Non-secure EL1 reads of MIDR.See
MIDR bit assignments
on
page 4-157
.
IminLine
31 30
28 27
24 23
20 19
16 15 14 13
4 3
0
CWG
ERG
DminLine
L1Ip
RES
0
RES
0
RES
1
Table 4-187 CTR bit assignments
Bits
Name
Function
[31]
-
Reserved,
RES
1.
[30:28]
-
Reserved,
RES
0.
[27:24]
CWG
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.
[23:20]
ERG
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.
[19:16]
DminLine
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.
[15:14]
L1lp
L1 Instruction cache policy. Indicates the indexing and tagging policy for the L1 Instruction cache:
0b10
Virtually Indexed Physically Tagged
(VIPT).
[13:4]
-
Reserved,
RES
0.
[3:0]
IminLine
Log
2
of the number of words in the smallest cache line of all the instruction caches that the processor controls.
0x4
Smallest instruction cache line size is 16 words.
Table 4-188 CTR access encoding
coproc
opc1
CRn
CRm
opc2
1111
010
0000
0000
001