Datasheet

PCI Express Non-Transparent Bridge
Intel
®
Xeon
®
Processor C5500/C3500 Series
Datasheet, Volume 1 February 2010
156 Order Number: 323103-001
If the configuration is NTB/RP then the secondary side of the NTB will be per the PCI
Express Base Specification, Revision 2.0. For this configuration the secondary side of
the NTB must capture the Bus and Device numbers supplied with all Type 0
Configuration Write requests sent across the link to the NTB.
For inbound reads received from the remote host, the NTB performs the address
translation and launches the memory read on the local processor. The completions
returned from memory are translated and returned back to the remote host using the
correct Completer ID (the secondary side of the NTB).
For outbound reads, the NTB performs the address translation and uses the captured
BDF as the Requester ID for the transaction sent across the link.
See Figure 58 and Figure 59 for examples of how Requester and Completer ID
translation are handled by hardware for the NTB/RP configuration.
Figure 58. NTB to RP Read Request, ID translation Example
JSPJSP
HOST A HOST A
HOST B HOST B
NTB A
NTB A
RCiEP
BDF 030
RCiEP
BDF 030
PCIE EP
BDF M,0,0
PCIE EP
BDF M,0,0
MRd
Req ID 0,0,0
MRd
Req ID M,0,0
Cmpl
Req ID 0,0,0
Cmptr ID 0,3,0
Memory Read request from
HOST A to HOST B
PCI EP captures Type 0 CFG
WR Request and uses for
requests and completions
Read
Request
Completion
RP
BDF 040
RP
BDF 040
Cmpl
Req ID M,0,0
Cmptr ID 0,4,0
MRd
Req ID 0,4,0
BDF 000
BDF 000
Cmpl
Req ID 0,4,0
Cmptr ID 0,0,0