1# Copyright (c) 2010 Advanced Micro Devices, Inc.
2# All rights reserved.
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15# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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26#
27# Authors: Steve Reinhardt
28
29from __future__ import print_function
30from __future__ import absolute_import
31
32from m5.params import *
33from m5.objects import *
34
35from .BaseTopology import SimpleTopology
36
37class Crossbar(SimpleTopology):
38    description='Crossbar'
39
40    def makeTopology(self, options, network, IntLink, ExtLink, Router):
41
42        # default values for link latency and router latency.
43        # Can be over-ridden on a per link/router basis
44        link_latency = options.link_latency # used by simple and garnet
45        router_latency = options.router_latency # only used by garnet
46
47        # Create an individual router for each controller plus one more for
48        # the centralized crossbar.  The large numbers of routers are needed
49        # because external links do not model outgoing bandwidth in the
50        # simple network, but internal links do.
51        # For garnet, one router suffices, use CrossbarGarnet.py
52
53        routers = [Router(router_id=i) for i in range(len(self.nodes)+1)]
54        xbar = routers[len(self.nodes)] # the crossbar router is the last router created
55        network.routers = routers
56
57        ext_links = [ExtLink(link_id=i, ext_node=n, int_node=routers[i],
58                             latency = link_latency)
59                        for (i, n) in enumerate(self.nodes)]
60        network.ext_links = ext_links
61
62        link_count = len(self.nodes)
63
64        int_links = []
65        for i in range(len(self.nodes)):
66            int_links.append(IntLink(link_id=(link_count+i),
67                                     src_node=routers[i],
68                                     dst_node=xbar,
69                                     latency = link_latency))
70
71        link_count += len(self.nodes)
72
73        for i in range(len(self.nodes)):
74            int_links.append(IntLink(link_id=(link_count+i),
75                                     src_node=xbar,
76                                     dst_node=routers[i],
77                                     latency = link_latency))
78
79        network.int_links = int_links
80