Intel Extensible Firmware Interface User Manual
Page 606

Extensible Firmware Interface Specification
14-66 12/01/02
Version
1.10
Another example is a USB Controller (interface number 0) that is connected to port 3 of a USB
Hub Controller (interface number 0), and this USB Hub Controller is connected to the port 1 of the
root hub. The shorthand notation for this device path is:
ACPI(PNP0A03,0)/PCI(1F|2)/USB(1,0)/USB(3,0)
.
Table 14-5 shows the device path for this USB Controller.
Table 14-5. Another USB Device Path Example
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 0x1F PCI
Function
0x11
0x01 0x02 PCI
Device
0x12 0x01 0x03
Generic Device Path Header
– Type Message Device Path
0x13
0x01 0x05 Sub
type
– USB
0x14
0x02 0x06 Length
– 0x06 bytes
0x16
0x01
0x01
Parent Hub Port Number.
0x17
0x01 0x00 Controller
Interface
Number.
0x18 0x01 0x03
Generic Device Path Header
– Type Message Device Path
0x19
0x01 0x05 Sub
type
– USB
0x1A
0x02 0x06 Length
– 0x06 bytes
0x1C
0x01
0x03
Parent Hub Port Number.
0x1D
0x01 0x00 Controller
Interface
Number.
0x1E 0x01 0xFF
Generic Device Path Header
– Type End of Hardware Device Path
0x1F 0x01 0xFF Sub
type
– End of Entire Device Path
0x20
0x02 0x04 Length
– 0x04 bytes