Level 1 Memory System
ARM DDI 0500D
Copyright © 2013-2014 ARM. All rights reserved.
6-11
ID021414
Non-Confidential
6.5.3
CHI transactions
Table 6-3
shows the CHI transactions that each type of memory access generates.
See the
ARM
®
AMBA
®
5 CHI Protocol Specification
for more information about CHI
transactions.
Table 6-3 CHI transactions
Attributes
CHI transaction
Memory type
Shareability
SnpAttr
Load
Store
Load
exclusive
Store
exclusive
Device
-
Non-snoopable
ReadNoSnp
WriteNoSnp
ReadNoSnp
and
Excl
set to
HIGH
WriteNoSnp
and
Excl
set to
HIGH
Normal, inner
Non-cacheable, outer
Non-cacheable
Non-shared Non-snoopable
ReadNoSnp
WriteNoSnp
ReadNoSnp
and
Excl
set to
HIGH
WriteNoSnp
and
Excl
set to
HIGH
Inner-shared
Outer-shared
Normal, inner
Non-cacheable, outer
Write-Back or
Write-Through, or
Normal, inner
Write-Through,
outer Write-Back,
Write-Through or
Non-cacheable, or
Normal inner
Write-Back outer
Non-cacheable or
Write-Through
Non-shared Non-snoopable
ReadNoSnp
WriteNoSnp
ReadNoSnp ReadNoSnp
Inner-shared
Non-snoopable
ReadNoSnp
WriteNoSnp
ReadNoSnp
with
Excl
set to
HIGH
WriteNoSnp
with
Excl
set to
HIGH
Outer-shared
Non-snoopable
Normal, inner
Write-Back, outer
Write-Back
Non-shared Non-snoopable
ReadNoSnp
WriteNoSnp
ReadNoSnp WriteNoSnp
Inner-shared
Inner snoopable
ReadShared
ReadUnique,
CleanUnique, or
MakeUnique if
allocating into
the cache, then a
WriteBackFull
when the line is
evicted.
WriteUniqueFull
or
WriteUniquePtl
if not allocating
into the cache.
ReadShared
with
Excl
set to
HIGH
CleanUnique
with
Excl
set to
HIGH if
required, then a
WriteBackFull
when the line is
evicted
Outer-shared
Outer snoopable