IDT 89HPES16NT2, User Manual

Page: 227 / 292

IDT Non-Transparent Mode Operation
PES16NT2 User Manual 10 - 97 April 15, 2008
Notes
Extended Configuration Space Access Registers
PCIE_ECFGADDR - Extended Configuration Space Access Address (0x0F8)
PCIE_ECFGDATA - Extended Configuration Space Access Data (0x0FC)
PCI Express Extended Capability Header
PCIE_PCIEECAP - PCI Express Extended Capability (0x100)
Bit
Field
Field
Name
Type
Default
Value
Description
1:0 Reserved RO 0x0 Reserved field.
7:2 REG RW 0x0 Register Number. This field selects the configuration reg-
ister number as defined by Section 7.2.2 of the PCI
Express Base Specification, Rev. 1.0a
11:8 EREG RW 0x0 Extended Register Number. This field selects the
extended configuration register number as defined by Sec-
tion 7.2.2 of the PCI Express Base Specification, Rev. 1.0a
31:12 Reserved RO 0x0 Reserved field.
Bit
Field
Field
Name
Type
Default
Value
Description
31:0 DATA RW 0x0 Configuration Data. A read from this field will return the
configuration space register value pointed to by the ECF-
GADDR register. A write to this field will update the con-
tents of the configuration space register pointed to by the
ECFGADDR register with the value written. For both reads
and writes, the byte enables correspond to those used to
access this field.
When the ECFGADDR register points to the ECFGDATA
register, then reads from ECFGDATA return zero and
writes are ignored. When the ECFGADDR register points
to itself, writes to the ECFGDATA register modify the con-
tents of the ECFGADDR register.
Note : Accessing the ECFGDATA or ECFGDATA data reg-
isters on the opposite side of the non-transparent bridge
produces undefined results.
Bit
Field
Field
Name
Type
Default
Value
Description
15:0 CAPID RO 0x0 Capability ID. The value of 0x0. indicates that the non-
transparent bridge endpoint does not implement any
extended capabilities.
19:16 CAPVER RO 0x0 Capability Version. Not applicable.
31:20 NXTPTR RO 0x0 Next Pointer. The value of 0x0 indicates that there are no
extended capabilities.