Pci Express Capability Structure - IDT 89HPES24T6G2 User Manual

IDT Configuration Registers
Notes
PES24T6G2 User Manual
Bit Field
Type
Field Name
4 VGA16EN RW
5 Reserved RO
6 SRESET RW
15:7 Reserved RO

PCI Express Capability Structure

PCIECAP - PCI Express Capability (0x040)
Bit Field
Type
Field Name
7:0 CAPID RO
15:8 NXTPTR RWL
19:16 VER RWL
23:20 TYPE RO
24 SLOT RWL
29:25 IMN RO
31:30 Reserved RO
Default
Value
0x0 VGA 16-bit Enable. This bit only has an effect when the VGAEN
bit is set in this register.
This read/write bit enables system configuration software to
select between 10-bit and 16-bit I/O space decoding for VGA
transactions.
0 - (bit10) Perform 10-bit decoding. I/O space aliasing occurs in
this mode.
1 - (bit16) Perform 16-bit decoding. No I/O space aliasing occurs
in this mode.
0x0 Reserved field.
0x0 Secondary Bus Reset. Setting this bit triggers a secondary bus
reset.
In the upstream port, setting this bit initiates a Upstream Second-
ary Bus Reset.
In a downstream port, setting this bit initiates a Downstream Sec-
ondary Bus Reset.
Port Configuration Registers must not be changed except as
required to update port status.
0x0 Reserved field.
Default
Value
0x10 Capability ID. The value of 0x10 identifies this capability as a
PCI Express capability structure.
0xC0 Next Pointer. This field contains a pointer to the next capability
structure.
0x2 PCI Express Capability Version. This field indicates the PCI-
SIG defined PCI Express capability structure version number.
The PES24T6G2 is compliant with the Express Capabilities Reg-
ister Expansion ECN.
Upstream: Port Type. This field identifies the type of switch port (upstream
0x5 or downstream).
Downstream:
0x6
0x0 Slot Implemented. This bit is set when the PCI Express link
associated with this Port is connected to a slot. This field does
not apply to an upstream port and should be set to zero.
0x0 Interrupt Message Number. The function is allocated only one
MSI. Therefore, this field is set to zero.
0x0 Reserved field.
8 - 20
Description
Description
April 30, 2013