Processor Configuration Registers
Intel
®
Core
TM
i7-620LE/UE, i7-610E, i5-520E and Intel
®
Celeron
®
Processor P4500, P4505 Series
Datasheet Addendum
April 2010
118
Document Number: 323178-002
6.2.39
LCTL - Link Control
B/D/F/Type:
0/6/0/PCI
Address Offset:
B0-B1h
Default Value:
0000h
Access:
RO; RW; RW-SC
Size:
16 bits
Allows control of PCI Express link.
Table 62. LCTL - Link Control Register (Sheet 1 of 3)
Bit
Access
Default
Value
RST/
PWR
Description
15:12
RO
0000b
Core
Reserved
11
RW
0b
Core
Link Autonomous Bandwidth Interrupt Enable (LABIE)
When Set, this bit enables the generation of an interrupt to
indicate that the Link Autonomous Bandwidth Status bit has been
Set.
This bit is not applicable and is reserved for Endpoint devices, PCI
Express to PCI/PCI-X bridges, and Upstream Ports of Switches.
Devices that do not implement the Link Bandwidth Notification
capability must hardwire this bit to 0b.
10
RW
0b
Core
Link Bandwidth Management Interrupt Enable (LBMIE)
When Set, this bit enables the generation of an interrupt to
indicate that the Link Bandwidth Management Status bit has been
Set.
This bit is not applicable and is reserved for Endpoint devices, PCI
Express to PCI/PCI-X bridges, and Upstream Ports of Switches.
9
RW
0b
Core
Hardware Autonomous Width Disable (HAWD)
When Set, this bit disables hardware from changing the Link
width for reasons other than attempting to correct unreliable Link
operation by reducing Link width.
Devices that do not implement the ability autonomously to
change Link width are permitted to hardwire this bit to 0b.
8
RO
0b
Core
Enable Clock Power Management (ECPM)
Applicable only for form factors that support a “Clock Request”
(CLKREQ#) mechanism, this enable functions as follows:
0b – Clock power management is disabled and device must hold
CLKREQ# signal low.
1b - When this bit is set to 1 the device is permitted to use
CLKREQ# signal to power manage link clock according to protocol
defined in appropriate form factor specification.
Default value of this field is 0b. Components that do not support
Clock Power Management (as indicated by a 0b value in the Clock
Power Management bit of the Link Capabilities Register) must
hardwire this bit to 0b.