Flexible routing and addressing

• US 20060242354A1
• Filed: 12/01/2005
• Published: 10/26/2006
• Est. Priority Date: 04/22/2005
• Status: Active Grant

• Current Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Torudbakken, Ola, Johnsen, Bjorn Dag
• Granted Patent: US 7,293,129 B2
• Time in Patent Office: Days
• US Class Current: 710/316
• CPC Class Codes: G06F 13/404 with address mapping

Abstract

At an ingress point to a shared transaction infrastructure, for example a shared PCI Express infrastructure, an entry in a segment table maps an address in a transaction packet to a target for the transaction packet. The entry in the segment table identifies one of a plurality of channel descriptors providing one or more of forwarding information for the transaction packet and information for constructing an additional header for the transaction packet.

Claims

1. A method of routing transactions via a shared infrastructure, the method comprising, at an infrastructure ingress point:

accessing an entry in a segment table mapping an address in a transaction packet to a target for the transaction packet; and

identifying one of a plurality of channel descriptors providing at least one of;

forwarding information for the transaction packet; and

information for constructing an additional header for the transaction packet.

2. The method of claim 1, comprising accessing an entry in the segment table using at least one bit of an address in the header of the transaction packet.

3. The method of claim 2, comprising using a plurality of high order bits of the address in the header of the transaction packet.

4. The method of claim 1, wherein the content of the entry in the segment table indexes an entry in a channel descriptor table.

5. The method of claim 4, wherein the entries in the segment table are of variable length.

6. The method of claim 1, wherein the forwarding information for the transaction packet includes at least one of:

a source identifier for the source of the transaction packet;

target address information for the transaction packet; and

a resource key identifying access rights for a target resource.

7. The method of claim 1, wherein the ingress point is an ingress port of an interconnect apparatus.

8. The method of claim 1, wherein the ingress point is a root complex.

9. The method of claim 1, for routing PCI Express transactions via a shared PCI Express infrastructure.

10. An interconnect apparatus for routing transactions via a shared infrastructure, the interconnect apparatus comprising:

at an infrastructure ingress point, a segment table operable to map an address in a transaction packet to a target for the transaction packet; and

an entry in the segment table identifying one of a plurality of channel descriptors providing at least one of;

forwarding information for the transaction packet; and

information for constructing an additional header for the transaction packet.

11. The interconnect apparatus of claim 10, operable to access an entry in the segment table using at least one bit of an address in the header of the transaction packet.

12. The interconnect apparatus of claim 11, operable to use a plurality of high order bits of the address in the header of the transaction packet.

13. The interconnect apparatus of claim 10, wherein the entry in the segment table contains an index to the channel descriptor.

14. The interconnect apparatus of claim 10, wherein the content of the entry in the segment table indexes an entry in a channel descriptor table.

15. The interconnect apparatus of claim 14, further comprising the channel descriptor table, wherein the entries in the segment table are of variable length.

16. The interconnect apparatus of claim 10, wherein the forwarding information for the transaction packet includes at least one of:

a source identifier for the source of the transaction packet;

target address information for the transaction packet; and

a resource key identifying access rights for a target resource.

17. The interconnect apparatus of claim 10, wherein the interconnect apparatus is a switch and the ingress point is an ingress port of the switch.

18. The interconnect apparatus of claim 10, wherein the transactions are PCI Express transactions and the shared infrastructure is a shared PCI Express infrastructure.

19. A computer system for routing transactions via a shared infrastructure, the computer system comprising:

at an infrastructure ingress point, a segment table operable to map an address in a transaction packet to a target for the transaction packet; and

an entry in the segment table identifying one of a plurality of channel descriptors providing at least one of;

forwarding information for the transaction packet; and

information for constructing an additional header for the transaction packet.