Mesh_XY.py revision 11664 
1# Copyright (c) 2010 Advanced Micro Devices, Inc.
2#               2016 Georgia Institute of Technology
3# All rights reserved.
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9# redistributions in binary form must reproduce the above copyright
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12# neither the name of the copyright holders nor the names of its
13# contributors may be used to endorse or promote products derived from
14# this software without specific prior written permission.
15#
16# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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19# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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26# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27#
28# Authors: Brad Beckmann
29#          Tushar Krishna
30
31from m5.params import *
32from m5.objects import *
33
34from BaseTopology import SimpleTopology
35
36# Creates a generic Mesh assuming an equal number of cache
37# and directory controllers.
38# XY routing is enforced (using link weights)
39# to guarantee deadlock freedom.
40
41class Mesh_XY(SimpleTopology):
42    description='Mesh_XY'
43
44    def __init__(self, controllers):
45        self.nodes = controllers
46
47    # Makes a generic mesh
48    # assuming an equal number of cache and directory cntrls
49
50    def makeTopology(self, options, network, IntLink, ExtLink, Router):
51        nodes = self.nodes
52
53        num_routers = options.num_cpus
54        num_rows = options.mesh_rows
55
56        # There must be an evenly divisible number of cntrls to routers
57        # Also, obviously the number or rows must be <= the number of routers
58        cntrls_per_router, remainder = divmod(len(nodes), num_routers)
59        assert(num_rows <= num_routers)
60        num_columns = int(num_routers / num_rows)
61        assert(num_columns * num_rows == num_routers)
62
63        # Create the routers in the mesh
64        routers = [Router(router_id=i) for i in range(num_routers)]
65        network.routers = routers
66
67        # link counter to set unique link ids
68        link_count = 0
69
70        # Add all but the remainder nodes to the list of nodes to be uniformly
71        # distributed across the network.
72        network_nodes = []
73        remainder_nodes = []
74        for node_index in xrange(len(nodes)):
75            if node_index < (len(nodes) - remainder):
76                network_nodes.append(nodes[node_index])
77            else:
78                remainder_nodes.append(nodes[node_index])
79
80        # Connect each node to the appropriate router
81        ext_links = []
82        for (i, n) in enumerate(network_nodes):
83            cntrl_level, router_id = divmod(i, num_routers)
84            assert(cntrl_level < cntrls_per_router)
85            ext_links.append(ExtLink(link_id=link_count, ext_node=n,
86                                    int_node=routers[router_id]))
87            link_count += 1
88
89        # Connect the remainding nodes to router 0.  These should only be
90        # DMA nodes.
91        for (i, node) in enumerate(remainder_nodes):
92            assert(node.type == 'DMA_Controller')
93            assert(i < remainder)
94            ext_links.append(ExtLink(link_id=link_count, ext_node=node,
95                                    int_node=routers[0]))
96            link_count += 1
97
98        network.ext_links = ext_links
99
100        # Create the mesh links.
101        int_links = []
102
103        # East output to West input links (weight = 1)
104        for row in xrange(num_rows):
105            for col in xrange(num_columns):
106                if (col + 1 < num_columns):
107                    east_out = col + (row * num_columns)
108                    west_in = (col + 1) + (row * num_columns)
109                    int_links.append(IntLink(link_id=link_count,
110                                             src_node=routers[east_out],
111                                             dst_node=routers[west_in],
112                                             src_outport="East",
113                                             dst_inport="West",
114                                             weight=1))
115                    link_count += 1
116
117        # West output to East input links (weight = 1)
118        for row in xrange(num_rows):
119            for col in xrange(num_columns):
120                if (col + 1 < num_columns):
121                    east_in = col + (row * num_columns)
122                    west_out = (col + 1) + (row * num_columns)
123                    int_links.append(IntLink(link_id=link_count,
124                                             src_node=routers[west_out],
125                                             dst_node=routers[east_in],
126                                             src_outport="West",
127                                             dst_inport="East",
128                                             weight=1))
129                    link_count += 1
130
131        # North output to South input links (weight = 2)
132        for col in xrange(num_columns):
133            for row in xrange(num_rows):
134                if (row + 1 < num_rows):
135                    north_out = col + (row * num_columns)
136                    south_in = col + ((row + 1) * num_columns)
137                    int_links.append(IntLink(link_id=link_count,
138                                             src_node=routers[north_out],
139                                             dst_node=routers[south_in],
140                                             src_outport="North",
141                                             dst_inport="South",
142                                             weight=2))
143                    link_count += 1
144
145        # South output to North input links (weight = 2)
146        for col in xrange(num_columns):
147            for row in xrange(num_rows):
148                if (row + 1 < num_rows):
149                    north_in = col + (row * num_columns)
150                    south_out = col + ((row + 1) * num_columns)
151                    int_links.append(IntLink(link_id=link_count,
152                                             src_node=routers[south_out],
153                                             dst_node=routers[north_in],
154                                             src_outport="South",
155                                             dst_inport="North",
156                                             weight=2))
157                    link_count += 1
158
159
160        network.int_links = int_links
161