21.1.4 ATA Device Paths

The table below shows an example device path for a ATA host controller that supports a single SCSI channel and is located at PCI device number 0x07 and PCI function 0x00 The PCI SCSI host controller is directly attached to a PCI root bridge.

This sample device path consists of an ACPI device path node, a PCI device path node, and a device path end structure. The _HID and _UID must match the ACPI table description of the PCI root bridge. The following is the shorthand notation for this device path: ACPI(PNP0A03,0)/PCI(7|0).

Table 34-SATA device path examples

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

0x07

PCI Function

0x11

0x01

0x00

PCI Device

0x12

0x01

0xFF

Generic Device Path Header - Type End of Hardware Device Path

0x13

0x01

0xFF

Sub type - End of Entire Device Path

0x14

0x02

0x04

Length - 0x04 bytes