Round robin arbitration using random access memory

An arbitration system comprising:

• a requestor random access memory (RRAM) having multiple entries, each entry corresponding to a requestor and including a valid field indicating whether or not the requestor is requesting;
• a group RAM having multiple group entries, each group entry corresponding to a group of requestors and including a group valid field indicating whether or not the group of requestors is requesting, a start pointer to a corresponding to the RRAM, an end pointer to the corresponding RRAM, and a last chosen pointer wherein one of the multiple entries in the group RAM is selectable in a round robin manner as a function of a value in the group valid field indicative of the corresponding group of requestors requesting;
• and
• arbitration circuitry configured to:
• receive requests for arbitration between the multiple requestors;
• perform round robin arbitration using the group RAM to select one of the multiple entries in the group RAM corresponding to a portion of the RRAM;
• access the RRAM to select one of the multiple entries in a round robin manner from the corresponding portion of the RRAM as a function of a value in the valid field indicative of the corresponding requestor requesting;
• and
• send an indication to the corresponding requesting requestor.

A method comprising:

• receiving arbitration requests at an arbitration processor from multiple requestors;
• performing round robin arbitration for each request using a group RAM having multiple group entries, each group entry corresponding to a group of requestors and including a group valid field indicating whether or not the group of requestors is requesting, a start pointer to a corresponding requestor random access memory (RRAM), an end pointer to the corresponding RRAM, and a last chosen pointer;
• selecting one of the multiple entries in the group RAM in a round robin manner as a function of a value in the group valid field indicative of the corresponding group of requestors requesting;
• sending set valid field request to the RRAM having multiple entries, each entry corresponding to a requestor and including a valid field;
• accessing a portion of the RRAM containing the corresponding group of requestors to select one of the multiple entries in a round robin manner as a function of a value in the valid field indicative of the corresponding requestor requesting;
• resetting the value in the valid field of the selected one of the multiple entries;
• and
• sending an arbitration done indication to the corresponding requestor.