
IDT Usage Models
PES32NT24xG2 User Manual
26 - 9
January 30, 2013
Notes
When the switch manager device wishes to receive global signals from partitions 0 and 1, it configures
the global signals mechanism as follows:
–
The SEGSIGMSK register is configured to unmask global signals from partitions 0 and 1.
–
The SEMSK register is configured to unmask global signals.
–
The SEPMSK register is configured to unmask event signals to partition 2.
When the switch manager device wishes to send global signals to partition 0, it configures the global
signals mechanism as follows:
–
The SEGSIGMSK register is configured to unmask global signals from partition2.
–
The SEMSK register is configured to unmask global signals.
–
The SEPMSK register is configured to unmask event signals to partition 0.
When the switch manager device wishes to send global signals to partition 1, it configures the global
signals mechanism as follows:
–
The SEGSIGMSK register is configured to unmask global signals from partition2.
–
The SEMSK register is configured to unmask global signals.
–
The SEPMSK register is configured to unmask event signals to partition 1.
–
The upstream ports in each partition are configured to unmask interrupts due to switch events.
–
The NTINTMSK register in port 16 is configured to unmask interrupt generation due to switch
events.
–
The P2PINTMSK register in ports 0 and 1 is configured to unmask interrupt generation due to
switch events.
Description
The switch mangement agent pre-configures the Global Signals mechanism to receive global signals
from partitions 0 and 1 (as described above). The root-complex in partition 0 (RC0) requests I/O resources
to the switch manager. It does so by using the global signaling mechanism as follows:
–
RC0 writes a message to the P2PSDATA register in port 0. The message is a system-specific
message requesting I/O resources. The encoding of such messages are outside the scope of this
specification.
–
RC0 sets the GSIGNAL field in the P2PGSIGNAL register in port 0. This triggers the global signal.
This causes a switch event to be generated to partition 2. As a result, an interrupt is generated by
the NT function in port 16 and sent to the switch manager device.
The switch manager device receives the interrupt and performs the following actions:
–
Reads the NTINTSTS register in port 16 to determine the interrupt’s cause.
–
Upon noticing the interrupt was caused by a switch event, reads the SESTS register to determine
the cause of the switch event.
–
Upon noticing the switch event was caused by a global signal, reads the SEGSIGSTS register to
determine the partition that issued the global signal.
The switch manager determines that it is partition 0 that issued the global signal, and reads the
P2PSDATA register in port 0 to obtain the message. The message indicates that port 0 is requesting I/O
resources. The message also indicates that port 0 has downstream port device numbers 0, 1, and 2 in its
partition already. The port migration process should take this into account to prevent conflicting device
numbers in the partition.
The switch manager re-arms the interrupt mechanism (by clearing the appropriate bits in the NTINTSTS
and SEGSIGSTS registers).
The switch manager decides to honor port 0’s request, and communicates with the root-complex in
partition 1 (RC1) indicating that port 8 is about to be migrated out of partition 1. To allow this communica-
tion, the switch manager device dynamically re-configures the global signal mechanism such that it can
send a global signal to partition 1 (as described above).
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...