
IDT Transparent Switch Operation
PES32NT24xG2 User Manual
10 - 6
January 30, 2013
Notes
An Assert_INTx message is sent to the root by the upstream port when the aggregated state of the
corresponding interrupt in the upstream port transitions from a negated to an asserted state. A
Deassert_INTx message is sent to the root by the upstream port when the aggregated state of the corre-
sponding interrupt in the upstream port function transitions from an asserted to a negated state. The
requester ID field in the Assert_INTx and Deassert_INTx messages has the upstream port’s bus and device
number. The function number is set to 0x0 and must be ignored by receivers per the PCI Express Base
Specification.
PCI-to-PCI bridges must map interrupts on the secondary side of the bridge according to the device
number of the device on the secondary side of the bridge. No mapping is performed for the PCI-to-PCI
bridges corresponding to downstream switch ports as these ports only connect to device zero. A mapping is
performed for the upstream port. This mapping is summarized in Table 10.3.
If a downstream switch port goes down (i.e., transition to DL_Down state) or is removed from a partition,
the INTx virtual wires associated with that port are negated, and the upstream port’s aggregate state is
updated accordingly. This may result in the upstream port generating a Deassert_INTx message. Refer to
section Port Operating Mode Change on page 5-13 for details on how port operating mode changes affect
the aggregated INTx state of a partition.
Access Control Services
The PCI-to-PCI bridge function supports Access Control Services (ACS) as defined in PCI Express
Base Specification. ACS functionality is performed by the PCI-to-PCI bridge function when the associated
port operates in the following modes:
–
Downstream switch port mode
–
Upstream switch port with NT function
–
Upstream switch port with DMA function
–
Upstream switch port with NT and DMA functions
The PCI-to-PCI bridge function does not support ACS checks when the port operates in any other
mode. When a port operates in downstream switch port mode, the PCI-to-PCI bridge function supports the
following ACS operations:
–
ACS Source Validation
–
ACS Translation Blocking
–
ACS Peer-to-Peer
1
Request Redirect
Upstream Port Interrupt
INTA
INTB
INTC
INTD
Downstream
Device
1
Interrupt
1.
Device X INTy corresponds to external downstream generated INTy interrupts and INTy interrupts generated by the
downstream port.
Device (N mod 4) =
0 INTA
Device (N mod 4) =
0 INTB
Device (N mod 4) =
0 INTC
Device (N mod 4) =
0 INTD
Device (N mod 4) =
1 INTD
Device (N mod 4) =
1 INTA
Device (N mod 4) =
1 INTB
Device (N mod 4) =
1 INTC
Device (N mod 4) =
2 INTC
Device (N mod 4) =
2 INTD
Device (N mod 4) =
2 INTA
Device (N mod 4) =
2 INTB
Device (N mod 4) =
3 INTB
Device (N mod 4) =
3 INTC
Device (N mod 4) =
3 INTC
Device (N mod 4) =
3 INTA
Table 10.3 Downstream to Upstream Port Interrupt Routing Based on Device Number
1.
For a port operating in downstream switch port mode, ‘peer-to-peer’ implies traffic received by the downstream
switch port (via the PCI Express link) that is destined towards another downstream switch port in the same parti-
tion.
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...