TCAM with efficient multiple dimension range search capability

摘要

An embodiment of the invention includes first and second Ternary Content Addressable Memories (TCAMs), a first vector, and TCAM match-merge unit. Each of the TCAMs includes a plurality of words, stores TCAM match entries and outputs a TCAM match signal for each word in the plurality of words. The first vector includes first TCAM group enable register bits. An enabling value on the first TCAM register bit indicates that the first TCAM match signal and the neighboring first TCAM match are in the same TCAM group. The TCAM match-merge unit receives the first TCAM match signal from each of the words and the first vector and outputs a first TCAM group match signal for each of the words. The TCAM match-merge unit outputs a match indication when any of the TCAM match signals indicate a match and outputs a mismatch when none of the TCAM match signals match.

主权项

1. An apparatus comprising:
a first Ternary Content Addressable Memory (TCAM), the first TCAM having a first plurality of words; wherein the first TCAM stores a first plurality of first TCAM match entries; wherein the first TCAM outputs a first TCAM match signal for each word in the first plurality of words; a second Ternary Content Addressable Memory (TCAM), the second TCAM having a second plurality of words; wherein the second TCAM stores a second plurality of second TCAM match entries; wherein the second TCAM outputs a second TCAM match signal for each word in the second plurality of words; a first TCAM grouping of enable register bits wherein a first TCAM enable register bit from the first TCAM group of enable register bits is logically located between each of the first TCAM match signal and a neighboring first TCAM match signal to the first TCAM match signal; where an enabling value on the first TCAM enable register bit indicates that the first TCAM match signal and the neighboring first TCAM match signal are in a same first TCAM group; a first TCAM match-merge unit, the first TCAM match-merge unit receiving the first TCAM match signal from each word in the first plurality of words, receiving the first TCAM grouping of enable register bits and outputting a first TCAM group match signal for each word in the first plurality of words; wherein the first TCAM match-merge unit is operable to output a match indication on each of the first TCAM group match signals in the same first TCAM group when any of the first TCAM match signals in the same first TCAM group indicates a match; wherein the first TCAM match-merge unit is operable to output a mismatch indication on each of the first TCAM group match signals in the same first TCAM group when none of the first TCAM match signals in the same first TCAM group indicates a match; and wherein the first TCAM group match signal for each word of the words enables the second TCAM match signal for the word.