Intel Extensible Firmware Interface User Manual
Page 539

Protocols
— SCSI Bus Support
Version 1.10
12/01/02
13-19
Table 13-2 shows an example device path for a single channel PCI SCSI 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 13-2. Single Channel PCI SCSI Controller behind a 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