gem5/src/mem/ruby/network/topologies/Crossbar.py

# Copyright (c) 2010 Advanced Micro Devices, Inc.
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# Authors: Steve Reinhardt

from m5.params import *
from m5.objects import *

class Crossbar(Topology):
    description='Crossbar'

def makeTopology(nodes, options, IntLink, ExtLink, Router):
    # Create an individual router for each controller plus one more for the
    # centralized crossbar.  The large numbers of routers are needed because
    # external links do not model outgoing bandwidth in the simple network, but
    # internal links do.
    cb = Crossbar()
    cb.routers = [Router(router_id=i) for i in range(len(nodes)+1)]
    cb.ext_links = [ExtLink(link_id=i, ext_node=n, int_node=cb.routers[i])
                    for (i, n) in enumerate(nodes)]
    link_count = len(nodes)
    xbar = cb.routers[len(nodes)] # the crossbar router is the last router created
    cb.int_links = [IntLink(link_id=(link_count+i),
                            node_a=cb.routers[i], node_b=xbar)
                    for i in range(len(nodes))]
    return cb