Intel Extensible Firmware Interface - Manual (Page 513)

Protocols — PCI Bus Support
Version 1.10 12/01/02 12-95
Table 12-13 shows an example device path for a PCI controller that is located behind a PCI to PCI
bridge at PCI device number 0x07 and PCI function 0x00. The PCI to PCI bridge is directly
attached to a PCI root bridge, and it is at PCI device number 0x05 and PCI function 0x00. This
device path consists of an ACPI Device Path Node, two PCI Device Path Nodes, and a Device Path
End Structure. The _HID and _UID must match the ACPI table description of the PCI Root
Bridge. The shorthand notation for this device path is:
ACPI(PNP0A03,0)/PCI(5|0)/PCI(7|0) .
Table 12-13. PCI Device 7, Function 0 behind PCI to PCI bridge
Byte
Offset Byte
Length
Data
Description
0x00 0x01 0x02 Generic Device Path Header – Type ACPI Device Path
0x01 0x01 0x01 Sub type – ACPI Device Path
0x02 0x02 0x0C Length – 0x0C bytes
0x04 0x04 0x41D0,
0x0A03
_HID PNP0A03 – 0x41D0 represents a compressed string ‘PNP’ and is in
the low order bytes.
0x08 0x04 0x0000 _UID
0x0C 0x01 0x01 Generic Device Path Header – Type Hardware Device Path
0x0D 0x01 0x01 Sub type – PCI
0x0E 0x02 0x06 Length – 0x06 bytes
0x10 0x01 0x00 PCI Function
0x11 0x01 0x05 PCI Device
0x12 0x01 0x01 Generic Device Path Header – Type Hardware Device Path
0x13 0x01 0x01 Sub type – PCI
0x14 0x02 0x06 Length – 0x06 bytes
0x16 0x01 0x00 PCI Function
0x17 0x01 0x07 PCI Device
0x18 0x01 0xFF Generic Device Path Header – Type End of Hardware Device Path
0x19 0x01 0xFF Sub type – End of Entire Device Path
0x1A 0x02 0x04 Length – 0x04 bytes