
IDT DMA Controller
PES32NT24xG2 User Manual
15 - 25
January 30, 2013
Notes
When the DMA function is configured to generate INTx messages, the specific INTx used (e.g., INTA,
INTB, etc.) depends on the programming of the Interrupt Pin (INTRPIN) register.
Virtual Channel (VC) Support
The DMA function supports per-descriptor traffic-class (TC) control for request TLPs that it transmits, as
described in section TLP Attribute and Traffic Class Control on page 15-20. Also, section Virtual Channel
Support on page 4-5 describes virtual channel support and TC/VC mapping in the switch ports.
The DMA function does not have a dedicated VC Capability Structure that defines TC/VC mapping.
Instead, TC/VC mapping is performed as specified in the VC Capability Structure associated with function 0
of the multi-function port in which the DMA function resides. Depending on the port operating mode, func-
tion 0 of the multi-function port may be a PCI-to-PCI bridge or NT function.
–
TLPs received by the DMA are checked for TC/VC mapping violations at the ingress port.
–
TLPs generated by the DMA are checked for TC/VC mapping at the egress port.
The DMA module does not perform any further TC/VC mapping checks. It is the responsibility of the
user to ensure that DMA descriptor traffic class controls map to VC0 within the PES32NT24xG2 switch
ports involved in the DMA transfer.
Access Control Services (ACS) Support
The DMA function supports the following ACS checks
1
:
–
ACS Peer-to-Peer
2
Request Redirect
–
ACS Peer-to-Peer Completion Redirect
ACS is programmed via the ACS Capability Structure in the DMA function’s configuration space. The
DMA does not support ACS Peer-to-Peer Completion redirect on completions generated by the DMA in
response to received requests that target DMA BAR 0. ACS Peer-to-Peer Completion Redirect is adver-
tised as supported in the DMA’s ACS Capability Structure, but it does not have any functional effect. Note
that completions TLPs generated by the DMA in response to received configuration request TLPs are
always routed upstream and therefore ACS has no functional effect on these completions either.
Table 15.10 lists ACS checking and handling performed by the DMA function.
Unmasked
Interrupt
EN bit in
MSICAP
Register
INTXD bit
in PCICMD
Register
Action
Asserted
1
X
MSI message generated
0
0
Assert_INTx message request generated
0
1
None
Negated
1
X
None
0
0
Deassert_INTx message request generated
0
1
None
Table 15.9 Downstream Switch Port Interrupts
1.
Note the DMA does not support Address Translation Services (ATS). As a result, the DMA function does not
support ACS Direct Translated P2P.
2.
For a port operating in a multi-function upstream port mode (e.g., upstream switch port with DMA function),
‘peer-to-peer’ implies traffic sent from one of the port functions to another (e.g., from the port’s DMA function to
the port’s PCI-to-PCI bridge function, etc.)
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...