Datasheet
PCI Express Non-Transparent Bridge
Intel
®
Xeon
®
Processor C5500/C3500 Series
Datasheet, Volume 1 February 2010
240 Order Number: 323103-001
3.20.2 Standard PCI Configuration Space (0x0 to 0x3F) - Type 0
Common Configuration Space
This section covers the secondary side registers in the 0x0 to 0x3F region that are
common to Bus M, Device 0. The Primary side of the NTB was discussed in the previous
section and is located on NTB Bus 0, Device 3. Comments at the top of the table
indicate what devices/functions the description applies to. Exceptions that apply to
specific functions are noted in the individual bit descriptions.
Note: Several registers will be duplicated in the three sections discussing the three modes it
operates in RP, NTB/NTB, and NTB/RP primary and secondary but are repeated here for
readability.
There are three access mechanisms to get to the secondary side configuration register.
• Conventional PCI BDF from the secondary side.
• MMIO from the primary side. This is needed in order to program the secondary side
configuration registers in the case of NTB/NTB. The registers are reached through
the primary side BAR01 memory window at an offset starting at 500h.
• MMIO from the secondary side. This is a secondary method to reach the same
registers and the conventional BDf mechanism. The registers are reached through
the secondary side BAR01 memory window at an offset starting at 500h.
3.20.2.1 VID: Vendor Identification Register
3.20.2.2 DID: Device Identification Register (Dev#N, PCIE NTB Sec Mode)
Register:VID
Bar:PB01BASE + 500h + Offset, SB01BASE + 500h + Offset
Bus:M
Device:0
Function: 0
Offset:00h
Bit Attr Default Description
15:0 RO 8086h
Vendor Identification Number
The value is assigned by PCI-SIG to Intel.
Register:DID
Bar:PB01BASE + 500h + Offset, SB01BASE + 500h + Offset
Bus:M
Device:0
Function: 0
Offset:02h
Bit Attr Default Description
15:0 RO 3727h
Device Identification Number
The value is assigned by Intel to each product. IIO will have a unique device id
for each of its PCI Express single function devices.