
IDT PCI-to-PCI Bridge Registers
PES32NT24xG2 User Manual
20 - 18
January 30, 2013
Notes
PCIELCAP - PCI Express Link Capabilities (0x04C)
Bit
Field
Field
Name
Type
Default
Value
Description
3:0
MAXLNKSPD
RWL
0x2
SWSticky
Maximum Link Speed.
This field indicates the supported link speeds of the port.
1 - (gen1) 2.5 GT/s
2 -
(gen2) 5 GT/s
others - reserved
Note: This device advertises support for 5 GT/s regardless
of the setting of this field. Modifying this field has no effect
on the hardware
9:4
MAXLNK-
WDTH
RWL
HWINIT
(see descrip-
tion)
MSWSticky
Maximum Link Width.
This field indicates the maximum link width of the given PCI
Express link.
This field may be overridden to allow the link width to be
forced to a smaller value.
When modifying this field, the user must ensure that all
functions of the port have identical values in this field (i.e.,
when the port operates in a multi-function mode). Violating
this rule produces undefined results.
Setting this field to an invalid or reserved value is allowed,
and results in the port operating at it’s default value.
The default value of this field is automatically set by the
hardware as described in section Port Maximum Link Width
on page 7-1.
0 - reserved
1 - (x1) x1 link width
2 - (x2) x2 link width
4 - (x4) x4 link width
8 - (x8) x8 link width
12 - (x12) x12 link width
16 - (x16) x16 link width
32-(x32) x32 link width
others - reserved
Note that this field is MSWSticky. Therefore, if this field is
modified by software, its value will be preserved regardless
of any stack configuration change.
11:10
ASPMS
RWL
0x3
SWSticky
Active State Power Management (ASPM) Support.
This default value of this field is 0x3 to indicate that L0s and
L1 are supported.
This field may be overridden to allow user control over the
ASPM capabilities of this port (L0s and/or L1).
When modifying this field, the user must ensure that all
functions of the port have identical values in this field (i.e.,
when the port operates in a multi-function mode).
14:12
L0SEL
RWL
0x6
SWSticky
L0s Exit Latency.
This field indicates the L0s exit latency for the given PCI
Express link. Transitioning from L0s to L0 always requires
approximately 2.04 µ s. Thus, default value indicates an L0s
exit latency between 2 µ s and 4 µ s.
If this field is modified, the user must ensure that all func-
tions of the port have identical values in this field (i.e., when
the port operates in a multi-function mode).
Summary of Contents for PCI Express 89HPES32NT24xG2
Page 20: ...IDT Table of Contents PES32NT24xG2 User Manual x January 30 2013 Notes...
Page 24: ...IDT List of Tables PES32NT24xG2 User Manual xiv January 30 2013 Notes...
Page 28: ...IDT List of Figures PES32NT24xG2 User Manual xviii January 30 2013 Notes...
Page 56: ...IDT PES32NT24xG2 Device Overview PES32NT24xG2 User Manual 1 20 January 30 2013 Notes...
Page 100: ...IDT Switch Core PES32NT24xG2 User Manual 4 22 January 30 2013 Notes...
Page 128: ...IDT Failover PES32NT24xG2 User Manual 6 4 January 30 2013 Notes...
Page 148: ...IDT Link Operation PES32NT24xG2 User Manual 7 20 January 30 2013 Notes...
Page 164: ...IDT SerDes PES32NT24xG2 User Manual 8 16 January 30 2013 Notes...
Page 170: ...IDT Power Management PES32NT24xG2 User Manual 9 6 January 30 2013 Notes...
Page 196: ...IDT Transparent Switch Operation PES32NT24xG2 User Manual 10 26 January 30 2013 Notes...
Page 244: ...IDT SMBus Interfaces PES32NT24xG2 User Manual 12 40 January 30 2013 Notes...
Page 247: ...IDT General Purpose I O PES32NT24xG2 User Manual 13 3 January 30 2013 Notes...
Page 248: ...IDT General Purpose I O PES32NT24xG2 User Manual 13 4 January 30 2013 Notes...
Page 330: ...IDT Switch Events PES32NT24xG2 User Manual 16 6 January 30 2013 Notes...
Page 342: ...IDT Multicast PES32NT24xG2 User Manual 17 12 January 30 2013 Notes...
Page 344: ...IDT Temperature Sensor PES32NT24xG2 User Manual 18 2 January 30 2013 Notes...
Page 384: ...IDT Register Organization PES32NT24xG2 User Manual 19 40 January 30 2013...
Page 492: ...IDT Proprietary Port Specific Registers PES32NT24xG2 User Manual 21 44 January 30 2013 Notes...
Page 588: ...IDT NT Endpoint Registers PES32NT24xG2 User Manual 22 96 January 30 2013 Notes...
Page 710: ...IDT JTAG Boundary Scan PES32NT24xG2 User Manual 25 12 January 30 2013 Notes...
Page 743: ...IDT Usage Models PES32NT24xG2 User Manual 26 33 January 30 2013 Notes...
Page 744: ...IDT Usage Models PES32NT24xG2 User Manual 26 34 January 30 2013 Notes...