Register Description
3.5.1.16
Offset 1Dh: IOL—I/O Limit Register (D0:F0, F2)
Offset:
Default Value: 00h
1Dh
Attribute: RW, RO
Size: 8 bits
This register defines the limit (aligned to a 4-Kbyte boundary) of the I/O area of the bridge.
Accesses from the PCI Express* interface that are within the ranges specified in this register will
be sent to PCI if the I/O space enable bit is set. Accesses from PCI that are outside the ranges
specified will master abort.
Bits
Type
Reset
Description
7:4
RW
0
I/O Limit Address Bits [15:12] (IOLA): Defines the top address of an
address range to determine when to forward I/O transactions from PCI
Express* to PCI. These bits correspond to address lines 15:12 for 4 KB
alignment. Bits [11:0] are assumed to be FFFh.
3:2
1:0
RW
RO
0
0
I/O Limit Address Bits [11:10] (IOLA1K): When the EN1K bit is set in the
Intel® 6700PXH 64-bit PCI Hub Configuration register (CNF), these bits
become read/write and are compared with I/O address bits [11:10] to
determine the 1 KB limit address. When the EN1K bit is cleared, this field
becomes Read Only.
RO
I/O Limit Addressing Capability (IOLC): These bits are hardwired to ‘0’,
indicating support for only 16-bit I/O addressing.
3.5.1.17
Offset 1Eh: SECSTS—Secondary Status Register
(D0:F0, F2)
Offset:
Default Value: 02A0h
1E–1Fh
Attribute: RWC, RO
Size: 16 bits
Bits
Type
Reset
Description
15
RWC
0
Detected Parity Error (DPE):
This bit reports the detection of an uncorrectable address, attribute or data
error by the Intel® 6700PXH 64-bit PCI Hub’s PCI/PCI-X interface. This bit is
set when any one of the following three conditions are true:
•
•
•
The Intel® 6700PXH 64-bit PCI Hub detects an uncorrectable address or
attribute error as a potential target.
The Intel® 6700PXH 64-bit PCI Hub detects an uncorrectable data error
when the target of a write transaction or a PCI-X Split Completion.
The Intel® 6700PXH 64-bit PCI Hub detects an uncorrectable data error
when the master of a read transaction (immediate read data or PCI-X Split
Response)
This bit gets set even if the Parity Error Response Enable bit (bit 0 of offset
3E–3Fh) of the Bridge Control Register.
0 = Uncorrectable address, attribute or data error not detected on the
PCI/PCI-X interface.
1 = Uncorrectable address, attribute or data error detected on the PCI/PCI-X
interface.
Software clears this bit by writing a 1 to it.
14
RWC
0
Received System Error (RSE):
This bit reports the detection of a SERR# assertion on the PCI/PCI-X
interface.
0 = SERR# assertion on the PCI/PCI-X interface has not been detected.
1 = SERR# assertion on the PCI/PCI-X interface has been detected.
Software clears this bit by writing a 1 to it.
Intel® 6700PXH 64-bit PCI Hub Datasheet
91