Method and apparatus for describing ACPI machine language in computer having multibridge PCI structure, and program thereof

Abstract

There is provided a method for describing an ACPI machine language table used in a computer system having a multibridge PCI structure, which enables an OS to support hot plugs for PCI devices subordinate to a PCI multibridge. Upon receiving a call requesting a resource information method for a PCI device from an ACPI driver on an OS, a PCI configuration access is made to a subordinate bridge in a PCI device side, so that the ACPI machine language table supplied from a BIOS returns resource information of the PCI device. A PCI configuration access is made to a superordinate bridge in a PCI system bus side, to obtain resource information of the subordinate bridge. The resource information of the subordinate bridge is obtained from the superordinate bridge, and secondary resource information is obtained from a PCI configuration space of the subordinate bridge.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 shows an exemplary configuration of an ACPI compatible system having a multibridge PCI structure according to an embodiment of the present invention;

FIG. 2 shows a virtual hardware configuration which is provided for an OS from a BIOS;

FIG. 3 is a flowchart showing operation through which an ACPI driver reads an AML table;

FIG. 4 is a flowchart showing how an ACPI driver obtains a bus number of a PCI device from an AML table; and

FIG. 5 shows a mechanism in which an ACPI driver carries out a status method in an AML.

Claims

1. A method for describing an ACPI machine language table for use in a computer having a multibridge structure that connects the computer to a PCI device via plural bridges from a PCI system bus, the method comprising steps of: making a PCI configuration access to a subordinate bridge in a PCI device side, so that the ACPI machine language table supplied from a BIOS returns resource information of the PCI device upon receiving a call requesting a resource information method for the PCI device from an ACPI driver on an OS;making a PCI configuration access to a superordinate bridge in a system bus side, to obtain resource information of the subordinate bridge; andobtaining the resource information of the subordinate bridge from the superordinate bridge, and obtaining secondary resource information from a PCI configuration space of the subordinate bridge.

2. The method according to claim 1, wherein the machine language table returns information concerning the superordinate and subordinate bridges as information hidden from the OS, as well as information concerning the PCI device as information not hidden from the OS.

3. An apparatus for describing an ACPI machine language table for use in a computer having a multibridge structure that connects the computer to a PCI device via plural bridges from a PCI system bus, said apparatus comprising: means for making a PCI configuration access to a subordinate bridge in a PCI device side, so that the ACPI machine language table supplied from a BIOS returns resource information of the PCI device upon receiving a call requesting a resource information method for the PCI device from an ACPI driver on an OS;means for making a PCI configuration access to a superordinate bridge in a system bus side, to obtain resource information of the subordinate bridge; andmeans for obtaining the resource information of the subordinate bridge from the superordinate bridge, and for obtaining secondary resource information from a PCI configuration space of the subordinate bridge.

4. The apparatus according to claim 3, wherein the machine language table returns information concerning the superordinate and subordinate bridges as information hidden from the OS, as well as information concerning the PCI device as information not hidden from the OS.

5. A program for causing a computer to execute a method for describing an ACPI machine language table for use in a computer having a multibridge structure that connects the computer to a PCI device via plural bridges from a PCI system bus, the method comprising steps of: making a PCI configuration access to a subordinate bridge in a PCI device side, so that the ACPI machine language table supplied from a BIOS returns resource information of the PCI device upon receiving a call requesting a resource information method for the PCI device from an ACPI driver on an OS;making a PCI configuration access to a superordinate bridge in a system bus side, to obtain resource information of the subordinate bridge; andobtaining the resource information of the subordinate bridge from the superordinate bridge, and obtaining secondary resource information from a PCI configuration space of the subordinate bridge.

6. The program according to claim 5, wherein the machine language table returns information concerning the superordinate and subordinate bridges as information hidden from the OS, as well as information concerning the PCI device as information not hidden from the OS.

7. A computer system having a multibridge structure that connects a computer to a PCI device via plural bridges from a PCI system bus, said computer system comprising an apparatus configured to describe an ACPI machine language table for use in the computer, said apparatus comprising: means for making a PCI configuration access to a subordinate bridge in a PCI device side, so that the ACPI machine language table supplied from a BIOS returns resource information of the PCI device upon receiving a call requesting a resource information method for the PCI device from an ACPI driver on an OS;means for making a PCI configuration access to a superordinate bridge in a system bus side, to obtain resource information of the subordinate bridge; andmeans for obtaining the resource information of the subordinate bridge from the superordinate bridge, and for obtaining secondary resource information from a PCI configuration space of the subordinate bridge.

8. The computer system according to claim 7, wherein the machine language table returns information concerning the superordinate and subordinate bridges as information hidden from the OS, as well as information concerning the PCI device as information not hidden from the OS.