Method and apparatus for performing repeated content addressable memory searches

A context pipeline circuit for providing an instruction and data to a content addressable memory (CAM), the context pipeline circuit comprising:

• an instruction pipeline for receiving the instruction and associated re-use data, and for providing the instruction to the CAM;
• a data pipeline for receiving current search data and providing the current search data from an output of the data pipeline;
• and,
• a data re-use circuit for receiving the re-use data from the instruction pipeline, the current search data from the output, and previously latched search data, the data re-use circuit selectively providing as the search data for performing a search of the CAM one of the current search data and the previously latched search data in response to a status of the re-use data.

A method for performing repeated searches on a content addressable memory (CAM), the method comprising:

• writing a plurality of data structures to context registers for performing searches of the CAM, each data structure having an instruction field for storing an instruction, a data field for storing search data and a data re-use field for storing a data re-use bit;
• selecting a context for execution in the CAM;
• forwarding the instruction of the selected context to the CAM;
• and,
• forwarding one of the search data of the selected context and the search data of another context to the CAM in response to a state of the data re-use bit.

A method for performing repeated searches on a content addressable memory (CAM), the method comprising:

• writing a plurality of data structures to context registers, each data structure having an instruction field for storing an instruction, a data field for storing search data for performing a search of the CAM, and a data reuse field for storing a data re-use bit;
• selecting a first context for execution in the CAM;
• forwarding the instruction and the search data of the first context to the CAM;
• selecting a second context for execution in the CAM;
• forwarding the instruction of the second context to the CAM;
• and
• forwarding one of the search data of the second context and the search data of the first context to the CAM in response to a state of the data re-use bit.