Doorbell mechanism

• US 20060235999A1
• Filed: 04/15/2005
• Published: 10/19/2006
• Est. Priority Date: 04/15/2005
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Tsao, Gary Y., Arizpe, Arturo L., Shah, Hemal V., Oztaskin, Ali S.
• Granted Patent: US 7,853,957 B2
• Time in Patent Office: Days
• US Class Current: 710/1
• CPC Class Codes: G06F 13/28 using burst mode transfer, e.g. direct memory access DMA, cycle steal G06F13/32 takes precedence
• CPC Class Codes: H04L 49/90 Buffering arrangements

Abstract

Provided are techniques for writing doorbell information. In accordance with certain techniques, one or more protection domains are created. One or more data structures are created, wherein each of the data structures is associated with at least one protection domain. One of the data structures is updated. A doorbell structure address for a doorbell structure associated with the updated data structure is computed. Doorbell information is written at the computed doorbell structure address. In accordance with certain other techniques, doorbell information is received. A doorbell structure address is decoded from the doorbell information. A first protection domain identifier is determined from the doorbell structure address. A resource context of a data structure is determined from the doorbell information. The resource context at the doorbell address is read to determine a second protection domain identifier. The first protection domain identifier and the second protection domain identifier are compared to determine whether to update the resource context of the doorbell structure. Other embodiments are described and claimed.

Claims

1. A method capable of writing doorbell information, comprising:

creating one or more protection domains;

creating one or more data structures, wherein each of the data structures is associated with at least one protection domain;

updating one of the data structures;

computing a doorbell structure address for a doorbell structure associated with the updated data structure; and

writing doorbell information at the computed doorbell structure address.

2. The method of claim 1, wherein the one or more data structures comprise a receive structure, a send structure, a completion structure, a shared receive structure and an event structure.

3. The method of claim 1, further comprising:

computing a doorbell structure address from a doorbell base address, a protection domain identifier associated with the updated data structure, a protection domain stride, and from a type of operation being performed.

4. The method of claim 3, wherein the doorbell information is transmitted to an Input/Output (I/O) device to write content for the doorbell structure at the doorbell structure address.

5. The method of claim 1, further comprising:

forming content for the doorbell structure.

6. A method capable of writing doorbell information, comprising:

receiving doorbell information;

decoding a doorbell structure address from the doorbell information;

determining a first protection domain identifier from the doorbell structure address;

determining a resource context of a data structure from the doorbell information;

reading the resource context to determine a second protection domain identifier; and

comparing the first protection domain identifier and the second protection domain identifier to determine whether to update the resource context.

7. The method of claim 6, further comprising:

updating the resource context with content provided in the doorbell information in response to determining that the first protection domain identifier and the second protection domain identifier match.

8. The method of claim 6, further comprising:

ignoring the doorbell information in response to determining that the first protection domain identifier and the second protection domain identifier do not match.

9. A system for writing doorbell information, comprising:

a motherboard;

an Input/Output device including a doorbell space and coupled to a bus; and

an Input/Output device driver coupled to the bus and coupled to the motherboard;

wherein the Input/Output device driver is operable to;

create one or more protection domains in the doorbell space;

create one or more data structures, wherein each of the data structures is associated with at least one protection domain;

update one of the data structures;

compute a doorbell structure address for a doorbell structure associated with the updated data structure; and

write doorbell information at the computed doorbell structure address.

10. The system of claim 9, wherein the one or more data structures comprise a receive structure, a send structure, a completion structure, a shared receive structure and an event structure.

11. The system of claim 9, wherein the Input/Output device driver is further operable to:

computer a doorbell structure address from a doorbell base address, a protection domain identifier associated with the updated data structure, a protection domain stride, and from a type of operation being performed.

12. The system of claim 11, wherein the doorbell information is transmitted to the Input/Output (I/O) device to write content for the doorbell structure at the doorbell structure address.

13. The system of claim 9, wherein the Input/Output device driver is further operable to:

form content for the doorbell structure.

14. A system for writing doorbell information, comprising:

a motherboard;

a doorbell space partitioned into one or more protection domains; and

an Input/Output controller coupled to the doorbell space and coupled to the motherboard;

wherein the Input/Output controller is operable to;

receive doorbell information;

decode a doorbell address from the doorbell information;

determine a first protection domain identifier from the doorbell structure address;

determine a resource context of a data structure from the doorbell information;

read the resource context to determine a second protection domain identifier; and

compare the first protection domain identifier and the second protection domain identifier to determine whether to update the resource context.

15. The system of claim 14, wherein the Input/Output controller is further operable to:

update the resource context with content provided in the doorbell information in response to determining that the first protection domain identifier and the second protection domain identifier match.

16. The system of claim 14, wherein the Input/Output controller is further operable to:

ignore the doorbell information in response to determining that the first protection domain identifier and the second protection domain identifier do not match.

17. An article of manufacture for writing doorbell information, wherein the article of manufacture comprises a computer readable medium storing instructions, and wherein the article of manufacture is operable to:

create one or more protection domains;

create one or more data structures, wherein each of the data structures is associated with at least one protection domain;

update one of the data structures;

compute a doorbell structure address for a doorbell structure associated with the updated data structure; and

write doorbell information at the computed doorbell structure address.

18. The article of manufacture of claim 17, wherein the one or more data structures comprise a receive structure, a send structure, a completion structure, a shared receive structure and an event structure.

19. The article of manufacture of claim 17, wherein the article of manufacture is further operable to:

compute a doorbell structure address from a doorbell base address, a protection domain identifier associated with the updated data structure, a protection domain stride, and from a type of operation being performed.

20. The article of manufacture of claim 19, wherein the doorbell information is transmitted to an Input/Output (I/O) device to write content for the doorbell structure at the doorbell structure address.

21. The article of manufacture of claim 17, wherein the article of manufacture is further operable to:

form content for the doorbell structure.

22. An article of manufacture for transmitting data, wherein the article of manufacture comprises a computer readable medium storing instructions, and wherein the article of manufacture is operable to:

receive doorbell information;

decode a doorbell address from the doorbell information;

determine a first protection domain identifier from the doorbell structure address;

determine a resource context of a data structure from the doorbell information;

read the resource context to determine a second protection domain identifier; and

compare the first protection domain identifier and the second protection domain identifier to determine whether to update the resource context.

23. The article of manufacture of claim 22, wherein the article of manufacture is further operable to:

update the resource context with content provided in the doorbell information in response to determining that the first protection domain identifier and the second protection domain identifier match.

24. The article of manufacture of claim 22, wherein the article of manufacture is further operable to:

ignore the doorbell information in response to determining that the first protection domain identifier and the second protection domain identifier do not match.