Intel
®
81341 and 81342—Address Translation Unit (PCI Express)
Intel
®
81341 and 81342 I/O Processors
Developer’s Manual
December 2007
352
Order Number: 315037-002US
3.16.62 PCI Express Link Control Register - PE_LCTL
This register controls various modes and features of ATU and Message Unit when
operating in the PCI Express mode.
Table 196. PCI Express Link Control Register PE_LCTL
Bit
Default
Description
15:8
00
2
Preserved
7
0
Extended Synch - This bit when set forces the transmission of 4096 FTS ordered sets in the L0s state
followed by a single SKP ordered set prior to entering the L0 state, and the transmission of 1024 TS1
ordered sets in the L1 state prior to entering the Recovery state. This mode provides external devices
(e.g., logic analyzers) monitoring the Link time to achieve bit and Symbol lock before the Link enters the
L0 or Recovery states and resumes communication.
6
0
Common Clock Configuration - When set indicates that this component and the component at the
opposite end of this Link are operating with a distributed common reference clock.
This bit used to report the correct L0s and L1 Exit Latencies in the PCIE_LCAP register
5
0
Retrain Link -
As an end point, this bit is hard-wired to 0
As a root complex, this bit initiates Link Retraining when set.
This bit is self clearing and always returns 0 when read.
4
0
Link Disable -
As and endpoint, this bit is hard-wired to 0
As a root complex, this bit disables the Link when set to 1b.
Writes to this bit are immediately reflected in the value read from the bit, regardless of actual Link state.
3
Endpoint: 0
Root
Complex:1
Read Completion Boundary (RCB) Control - Indicates the Root Complex’s RCB.
As an end point, this field is not supported and is hard-wired to 0.
For Root Complex, Hard-wired to 1b indicting 128Byte RCB
2
0
Reserved
1:0
00
Active State PM Control - This field controls the level of active state PM supported on the given PCI
Express Link.
PCI
IOP
Attributes
Attributes
15
12
8
4
0
pr
pr
pr
pr
pr
pr
pr
pr
pr
pr
pr
pr
pr
pr
pr
pr
rw
rw
rw
rw
rw
rw
rw
rw
ro
ro
pr
pr
rw
rw
rw
rw
Attribute Legend:
RV = Reserved
PR = Preserved
RS = Read/Set
RW = Read/Write
RC = Read Clear
RO = Read Only
NA = Not Accessible
Internal Bus Address Offset
+0E0H