Intel Extensible Firmware Interface User Manual
Page 463
Protocols
— PCI Bus Support
Version 1.10
12/01/02
12-45
Table 12-9 shows an example device path for a PCI Root Bridge using an Expanded ACPI Device
Path. This device path consists of an Expanded ACPI Device Path Node, and a Device Path End
Structure. The _UID and _CID fields must match the ACPI table description of the PCI Root
Bridge. For a system with only one PCI Root Bridge, the _UID value is usually 0x0000. The
shorthand notation for this device path is
ACPI(12345678,0,PNP0A03)
.
Table 12-9. PCI Root Bridge Device Path Using Expanded ACPI Device Path
Byte
Offset
Byte
Length
Data
Description
0x00
Á
0x01
Á
0x02
Á
@pypthÁ7pthpÁIf sÁApfipÁ– Type ACPI Device Path
Á
0x01
Á
0x01
Á
0x02
Á
Sub type – Expanded ACPI Device Path
Á
0x02
Á
0x02
Á
0x10
Á
Length – 0x10 bytes
Á
0x04
Á
0x04
Б
!Б
"#$%Б
_HID-device specific
Á
0x08
Á
0x04
Á
0x0000
Á
_UID
6Б
!Б
0x41D0,
0x0A03
Á
_CID PNP0A03 – 0x41D0 represents a compressed string ‘PNP’ and is
in the low order bytes.
0x10
Á
0x01
Á
0xFF
Á
@pypthÁ7pthpÁIf sÁApfipÁ– Type End of Hardware Device Path
Á
0x11
Á
0x01
Á
0xFF
Á
Sub type – End of Entire Device Path
Á
0x12
Á
0x02
Á
0x04
Á
Length – 0x04 bytes
Б