
IDT Switch Partition and Port Configuration
PES32NT24xG2 User Manual
5 - 19
January 30, 2013
Notes
L0s ASPM
A switch partition exhibits a correlation between the L0s ASPM state of its upstream and downstream
switch port(s). Refer to section Link Active State Power Management (ASPM) on page 7-12 and to the PCI
Express Base Specification 2.1 for details.
Downstream switch port addition
A switch partition must initiate an exit from L0s on the transmitter of the upstream switch port if it detects
an exit from L0s on the receiver of any downstream switch port. Adding a downstream switch port to a parti-
tion causes it to affect the L0s ASPM state of upstream switch port in the destination partition.
–
If the upstream switch port’s transmitter is in L0 and a downstream switch port whose receiver is
in L0s is added to the partition, then an entry to L0s may be initiated on the transmitter of the
upstream port per the rules described in section Link Active State Power Management (ASPM)
on page 7-12.
–
If the upstream port’s transmitter is in L0s and a downstream switch port whose receiver is in L0
is added to the partition, then an exit from L0s is initiated on the transmitter of the upstream port.
Adding a downstream switch port to a partition causes the added port to be affected by the L0s ASPM
state of the upstream switch port in the destination partition. For example, if a downstream switch port
whose transmitter is in L0 is added to a switch partition whose upstream switch port receiver is in L0s, then
an entry to L0s is initiated on the added port’s transmitter per the rules described in section Link Active
State Power Management (ASPM) on page 7-12.
Also, if a downstream switch port whose transmitter is in L0s is added to a switch partition whose
upstream switch port receiver is in L0, then an exit from L0s is initiated on the added port’s transmitter.
Upstream switch port addition
A switch partition must initiate an exit from L0s on the transmitters of all downstream switch ports asso-
ciated with the partition if it detects an exit from L0s on the receiver of its upstream switch port. See the PCI
Express Base Specification for details. Adding an upstream switch port to a partition causes it to affect the
L0s ASPM state of downstream switch ports in the destination partition.
–
If an upstream switch port whose receiver is in L0s is added to a switch partition, then an entry to
L0s is initiated on the transmitter of all downstream switch ports in L0 per the rules described in
section Link Active State Power Management (ASPM) on page 7-12.
–
If an upstream switch port whose receiver is in L0 is added to a switch partition, then an exit from
L0s is initiated on the transmitter of all downstream switch ports that are in L0s.
Adding an upstream switch port to a partition causes the added port to be affected by the L0s ASPM
state of downstream switch ports in the destination partition. For example, if an upstream switch port whose
transmitter is in L0 is added to a switch partition whose downstream switch ports are in L0s, then an entry to
L0s may initiated on the port’s transmitter per the rules described in section Link Active State Power
Management (ASPM) on page 7-12.
Also, if an upstream switch port whose transmitter is in L0s is added to a switch partition whose down-
stream switch ports are in L0, then an exit from L0s is initiated on the port’s transmitter.
L1 ASPM
Downstream switch port addition
An upstream switch port is not allowed to initiate entry into L1 unless all of the downstream switch ports
associated with the partition are in an L1 (or deeper) state. See section Link Active State Power Manage-
ment (ASPM) on page 7-12 and to the PCI Express Base Specification for details. Adding a downstream
switch port to a partition causes it to affect the L1 ASPM initiation of the upstream switch port. For example,
if a downstream switch port in L0 is added to a switch partition whose upstream switch port is in L1 ASPM,
then an exit from L1 is initiated on the upstream switch port.
Adding a downstream switch port to a partition causes the added port to be affected by the ASPM state
of the upstream switch port in the destination partition. For example, if a downstream switch port in L1
ASPM is added to a switch partition whose upstream switch port is in L0, then an exit from L1 is initiated on
the added port.
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...