Intel
®
81341 and 81342 I/O Processors
December 2007
Developer’s Manual
Order Number: 315037-002US
237
Address Translation Unit (PCI Express)—Intel
®
81341 and 81342
Figure 24. ATU Queue Architecture Block Diagram
PC
I
E
xp
re
ss
Li
n
k
La
ye
r
Inbound Posted Data Queue
(IPDQ)
4KBytes
Inbound Completion Data Queue
( ICPLDQ)
KBytes*
Inbound Completion Header Queue
( ICPLHQ)
32 Entries*
Inbound Posted Header Queue
(IPHQ)
16 Entries
Inbound Non Posted Header
( INPHQ)
8 Entries
Outbound Posted Data Queue
( OPDQ)
4KBytes
Outbound Completion Data Queue
( OCPLDQ)
4KBytes
Outbound Completion Header Queue
( OCPLHQ)
8 Entries
Outbound Posted Header Queue
( OPHQ)
4 Entries
Non Posted Data Queue
( ONPDQ)
1 Entry
In
te
rn
al
B
u
s
In
te
rfa
ce
In
te
rn
al
B
u
s
PC
I
E
xp
re
ss
Li
n
k
Outbound Non Posted Header
( ONPHQ)
8 Entries
Non Posted Data Queue
(INPDQ)
1 Entry
B6333-01
Note: As an endpoint, the ATU advertises infinite completion header
and completion date credits. The actual data space is 4KBytest and
supports up to 32 outstanding read requests.