ruby: changes how Topologies are created

Instead of just passing a list of controllers to the makeTopology function
in src/mem/ruby/network/topologies/<Topo>.py we pass in a function pointer
which knows how to make the topology, possibly with some extra state set
in the configs/ruby/<protocol>.py file. Thus, we can move all of the files
from network/topologies to configs/topologies. A new class BaseTopology
is added which all topologies in configs/topologies must inheirit from and
follow its API.

--HG--
rename : src/mem/ruby/network/topologies/Crossbar.py => configs/topologies/Crossbar.py
rename : src/mem/ruby/network/topologies/Mesh.py => configs/topologies/Mesh.py
rename : src/mem/ruby/network/topologies/MeshDirCorners.py => configs/topologies/MeshDirCorners.py
rename : src/mem/ruby/network/topologies/Pt2Pt.py => configs/topologies/Pt2Pt.py
rename : src/mem/ruby/network/topologies/Torus.py => configs/topologies/Torus.py

7 files changed, 658 insertions, 0 deletions

diff --git a/configs/topologies/BaseTopology.py b/configs/topologies/BaseTopology.py
new file mode 100644
index 000000000..114a29f19
--- /dev/null
+++ b/configs/topologies/BaseTopology.py
@@ -0,0 +1,51 @@
+# Copyright (c) 2012 Advanced Micro Devices, Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Jason Power
+
+
+class BaseTopology(object):
+    description = "BaseTopology"
+
+    def __init__(self):
+        """ When overriding place any objects created in
+            configs/ruby/<protocol>.py that are needed in
+            makeTopology (below) here. The minimum is usually
+            all of the controllers created in the above file.
+        """
+
+    def makeTopology(self, options, IntLink, ExtLink, Router):
+        """ Called from src/mem/ruby/network/topologies/TopologyCreatory.py
+            The return value is ( list(Router), list(IntLink), list(ExtLink))
+            The API of this function cannot change when subclassing!!
+            Any additional information needed to create this topology should
+            be passed into the constructor when it's instantiated in
+            configs/ruby/<protocol>.py
+        """
+        print "BaseTopology should have been overridden in a sub class!!"
+        import sys
+        sys.exit(1)
+
diff --git a/configs/topologies/Cluster.py b/configs/topologies/Cluster.py
new file mode 100644
index 000000000..e5c6dac0e
--- /dev/null
+++ b/configs/topologies/Cluster.py
@@ -0,0 +1,117 @@
+# Copyright (c) 2012 Advanced Micro Devices, Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Jason Power
+
+
+from BaseTopology import BaseTopology
+
+class Cluster(BaseTopology):
+    """ A cluster is a group of nodes which are all one hop from eachother
+        Clusters can also contain other clusters
+        When creating this kind of topology, return a single cluster (usually
+        the root cluster) from create_system in configs/ruby/<protocol>.py
+    """
+
+    _num_int_links = 0
+    _num_ext_links = 0
+    _num_routers = 0
+
+    # Below methods for auto counting
+    @classmethod
+    def num_int_links(cls):
+        cls._num_int_links += 1
+        return cls._num_int_links - 1
+    @classmethod
+    def num_ext_links(cls):
+        cls._num_ext_links += 1
+        return cls._num_ext_links - 1
+    @classmethod
+    def num_routers(cls):
+        cls._num_routers += 1
+        return cls._num_routers - 1
+
+    def __init__(self, intBW=0, extBW=0, intLatency=0, extLatency=0):
+        """ internalBandwidth is bandwidth of all links within the cluster
+            externalBandwidth is bandwidth from this cluster to any cluster
+                connecting to it.
+            internal/externalLatency are similar
+            **** When creating a cluster with sub-clusters, the sub-cluster
+                 external bandwidth overrides the internal bandwidth of the
+                 super cluster
+        """
+        self.nodes = []
+        self.router = None # created in makeTopology
+        self.intBW = intBW
+        self.extBW = extBW
+        self.intLatency = intLatency
+        self.extLatency = extLatency
+
+    def add(self, node):
+        self.nodes.append(node)
+
+    def makeTopology(self, options, IntLink, ExtLink, Router):
+        """ Recursively make all of the links and routers
+        """
+        routers = []
+        int_links = []
+        ext_links = []
+
+        # make a router to connect all of the nodes
+        self.router = Router(router_id=self.num_routers())
+        routers.append(self.router)
+        for node in self.nodes:
+            if type(node) == Cluster:
+                subRouters, subIntLinks, subExtLinks = node.makeTopology(options, IntLink, ExtLink, Router)
+                routers += subRouters
+                int_links += subIntLinks
+                ext_links += subExtLinks
+
+                # connect this cluster to the router
+                link = IntLink(link_id=self.num_int_links(), node_a=self.router, node_b=node.router)
+                if node.extBW:
+                    link.bandwidth_factor = node.extBW
+                elif self.intBW: # if there is an interanl b/w for this node and no ext b/w to override
+                    link.bandwidth_factor = self.intBW
+
+                if node.extLatency:
+                    link.latency = node.extLatency
+                elif self.intLatency:
+                    link.latency = self.intLatency
+
+                int_links.append(link)
+            else:
+                # node is just a controller connect it to the router via a ext_link
+                link = ExtLink(link_id=self.num_ext_links(), ext_node=node, int_node=self.router)
+                if self.intBW:
+                    link.bandwidth_factor = self.intBW
+                if self.intLatency:
+                    link.latency = self.intLatency
+
+                ext_links.append(link)
+
+        return routers, int_links, ext_links
+
diff --git a/configs/topologies/Crossbar.py b/configs/topologies/Crossbar.py
new file mode 100644
index 000000000..e66492922
--- /dev/null
+++ b/configs/topologies/Crossbar.py
@@ -0,0 +1,56 @@
+# Copyright (c) 2010 Advanced Micro Devices, Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Steve Reinhardt
+
+from m5.params import *
+from m5.objects import *
+
+from BaseTopology import BaseTopology
+
+class Crossbar(BaseTopology):
+    description='Crossbar'
+
+    def __init__(self, controllers):
+        self.nodes = controllers
+
+    def makeTopology(self, 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.
+
+        routers = [Router(router_id=i) for i in range(len(self.nodes)+1)]
+        ext_links = [ExtLink(link_id=i, ext_node=n, int_node=routers[i])
+                        for (i, n) in enumerate(self.nodes)]
+        link_count = len(self.nodes)
+        xbar = routers[len(self.nodes)] # the crossbar router is the last router created
+        int_links = [IntLink(link_id=(link_count+i),
+                             node_a=routers[i], node_b=xbar)
+                        for i in range(len(self.nodes))]
+
+        return routers, int_links, ext_links
+
diff --git a/configs/topologies/Mesh.py b/configs/topologies/Mesh.py
new file mode 100644
index 000000000..b1f2e6751
--- /dev/null
+++ b/configs/topologies/Mesh.py
@@ -0,0 +1,114 @@
+# Copyright (c) 2010 Advanced Micro Devices, Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Brad Beckmann
+
+from m5.params import *
+from m5.objects import *
+
+from BaseTopology import BaseTopology
+
+class Mesh(BaseTopology):
+    description='Mesh'
+
+    def __init__(self, controllers):
+        self.nodes = controllers
+
+    # Makes a generic mesh assuming an equal number of cache and directory cntrls
+
+    def makeTopology(self, options, IntLink, ExtLink, Router):
+        nodes = self.nodes
+
+        num_routers = options.num_cpus
+        num_rows = options.mesh_rows
+
+        # There must be an evenly divisible number of cntrls to routers
+        # Also, obviously the number or rows must be <= the number of routers
+        cntrls_per_router, remainder = divmod(len(nodes), num_routers)
+        assert(num_rows <= num_routers)
+        num_columns = int(num_routers / num_rows)
+        assert(num_columns * num_rows == num_routers)
+
+        # Create the routers in the mesh
+        routers = [Router(router_id=i) for i in range(num_routers)]
+
+        # link counter to set unique link ids
+        link_count = 0
+
+        # Add all but the remainder nodes to the list of nodes to be uniformly
+        # distributed across the network.
+        network_nodes = []
+        remainder_nodes = []
+        for node_index in xrange(len(nodes)):
+            if node_index < (len(nodes) - remainder):
+                network_nodes.append(nodes[node_index])
+            else:
+                remainder_nodes.append(nodes[node_index])
+
+        # Connect each node to the appropriate router
+        ext_links = []
+        for (i, n) in enumerate(network_nodes):
+            cntrl_level, router_id = divmod(i, num_routers)
+            assert(cntrl_level < cntrls_per_router)
+            ext_links.append(ExtLink(link_id=link_count, ext_node=n,
+                                    int_node=routers[router_id]))
+            link_count += 1
+
+        # Connect the remainding nodes to router 0.  These should only be
+        # DMA nodes.
+        for (i, node) in enumerate(remainder_nodes):
+            assert(node.type == 'DMA_Controller')
+            assert(i < remainder)
+            ext_links.append(ExtLink(link_id=link_count, ext_node=node,
+                                    int_node=routers[0]))
+            link_count += 1
+
+        # Create the mesh links.  First row (east-west) links then column
+        # (north-south) links
+        int_links = []
+        for row in xrange(num_rows):
+            for col in xrange(num_columns):
+                if (col + 1 < num_columns):
+                    east_id = col + (row * num_columns)
+                    west_id = (col + 1) + (row * num_columns)
+                    int_links.append(IntLink(link_id=link_count,
+                                            node_a=routers[east_id],
+                                            node_b=routers[west_id],
+                                            weight=1))
+                    link_count += 1
+
+        for col in xrange(num_columns):
+            for row in xrange(num_rows):
+                if (row + 1 < num_rows):
+                    north_id = col + (row * num_columns)
+                    south_id = col + ((row + 1) * num_columns)
+                    int_links.append(IntLink(link_id=link_count,
+                                            node_a=routers[north_id],
+                                            node_b=routers[south_id],
+                                            weight=2))
+                    link_count += 1
+
+        return routers, int_links, ext_links
diff --git a/configs/topologies/MeshDirCorners.py b/configs/topologies/MeshDirCorners.py
new file mode 100644
index 000000000..23bcde5a6
--- /dev/null
+++ b/configs/topologies/MeshDirCorners.py
@@ -0,0 +1,134 @@
+# Copyright (c) 2010 Advanced Micro Devices, Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Brad Beckmann
+
+from m5.params import *
+from m5.objects import *
+
+from BaseTopology import BaseTopology
+
+class MeshDirCorners(BaseTopology):
+    description='MeshDirCorners'
+
+    def __init__(self, controllers):
+        self.nodes = controllers
+
+    # This file contains a special network creation function.  This
+    # networks is not general and will only work with specific system
+    # configurations.  The network specified is similar to GEMS old file
+    # specified network.
+
+    def makeTopology(self, options, IntLink, ExtLink, Router):
+        nodes = self.nodes
+
+        num_routers = options.num_cpus
+        num_rows = options.mesh_rows
+
+        # First determine which nodes are cache cntrls vs. dirs vs. dma
+        cache_nodes = []
+        dir_nodes = []
+        dma_nodes = []
+        for node in nodes:
+            if node.type == 'L1Cache_Controller' or \
+            node.type == 'L2Cache_Controller':
+                cache_nodes.append(node)
+            elif node.type == 'Directory_Controller':
+                dir_nodes.append(node)
+            elif node.type == 'DMA_Controller':
+                dma_nodes.append(node)
+
+        # Obviously the number or rows must be <= the number of routers
+        # and evenly divisible.  Also the number of caches must be a
+        # multiple of the number of routers and the number of directories
+        # must be four.
+        assert(num_rows <= num_routers)
+        num_columns = int(num_routers / num_rows)
+        assert(num_columns * num_rows == num_routers)
+        caches_per_router, remainder = divmod(len(cache_nodes), num_routers)
+        assert(remainder == 0)
+        assert(len(dir_nodes) == 4)
+
+        # Create the routers in the mesh
+        routers = [Router(router_id=i) for i in range(num_routers)]
+
+        # link counter to set unique link ids
+        link_count = 0
+
+        # Connect each cache controller to the appropriate router
+        ext_links = []
+        for (i, n) in enumerate(cache_nodes):
+            cntrl_level, router_id = divmod(i, num_routers)
+            assert(cntrl_level < caches_per_router)
+            ext_links.append(ExtLink(link_id=link_count, ext_node=n,
+                                    int_node=routers[router_id]))
+            link_count += 1
+
+        # Connect the dir nodes to the corners.
+        ext_links.append(ExtLink(link_id=link_count, ext_node=dir_nodes[0],
+                                int_node=routers[0]))
+        link_count += 1
+        ext_links.append(ExtLink(link_id=link_count, ext_node=dir_nodes[1],
+                                int_node=routers[num_columns - 1]))
+        link_count += 1
+        ext_links.append(ExtLink(link_id=link_count, ext_node=dir_nodes[2],
+                                int_node=routers[num_routers - num_columns]))
+        link_count += 1
+        ext_links.append(ExtLink(link_id=link_count, ext_node=dir_nodes[3],
+                                int_node=routers[num_routers - 1]))
+        link_count += 1
+
+        # Connect the dma nodes to router 0.  These should only be DMA nodes.
+        for (i, node) in enumerate(dma_nodes):
+            assert(node.type == 'DMA_Controller')
+            ext_links.append(ExtLink(link_id=link_count, ext_node=node, int_node=routers[0]))
+
+        # Create the mesh links.  First row (east-west) links then column
+        # (north-south) links
+        int_links = []
+        for row in xrange(num_rows):
+            for col in xrange(num_columns):
+                if (col + 1 < num_columns):
+                    east_id = col + (row * num_columns)
+                    west_id = (col + 1) + (row * num_columns)
+                    int_links.append(IntLink(link_id=link_count,
+                                            node_a=routers[east_id],
+                                            node_b=routers[west_id],
+                                            weight=1))
+                    link_count += 1
+
+        for col in xrange(num_columns):
+            for row in xrange(num_rows):
+                if (row + 1 < num_rows):
+                    north_id = col + (row * num_columns)
+                    south_id = col + ((row + 1) * num_columns)
+                    int_links.append(IntLink(link_id=link_count,
+                                            node_a=routers[north_id],
+                                            node_b=routers[south_id],
+                                            weight=2))
+                    link_count += 1
+
+        return routers, int_links, ext_links
diff --git a/configs/topologies/Pt2Pt.py b/configs/topologies/Pt2Pt.py
new file mode 100644
index 000000000..360811272
--- /dev/null
+++ b/configs/topologies/Pt2Pt.py
@@ -0,0 +1,60 @@
+# Copyright (c) 2011 Advanced Micro Devices, Inc.
+#               2011 Massachusetts Institute of Technology
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Brad Beckmann
+#          Tushar Krishna
+
+from m5.params import *
+from m5.objects import *
+
+from BaseTopology import BaseTopology
+
+class Pt2Pt(BaseTopology):
+    description='Pt2Pt'
+
+    def __init__(self, controllers):
+        self.nodes = controllers
+
+    def makeTopology(self, options, IntLink, ExtLink, Router):
+        nodes = self.nodes
+        # Create an individual router for each controller, and connect all to all.
+
+        routers = [Router(router_id=i) for i in range(len(nodes))]
+        ext_links = [ExtLink(link_id=i, ext_node=n, int_node=routers[i])
+                    for (i, n) in enumerate(nodes)]
+        link_count = len(nodes)
+
+        int_links = []
+        for i in xrange(len(nodes)):
+            for j in xrange(len(nodes)):
+                if (i != j):
+                    link_count += 1
+                    int_links.append(IntLink(link_id=link_count,
+                                            node_a=routers[i],
+                                            node_b=routers[j]))
+
+        return routers, int_links, ext_links
diff --git a/configs/topologies/Torus.py b/configs/topologies/Torus.py
new file mode 100644
index 000000000..7fbcbf55b
--- /dev/null
+++ b/configs/topologies/Torus.py
@@ -0,0 +1,126 @@
+# Copyright (c) 2011 Advanced Micro Devices, Inc.
+#               2011 Massachusetts Institute of Technology
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Brad Beckmann
+#          Tushar Krishna
+
+from m5.params import *
+from m5.objects import *
+
+from BaseTopology import BaseTopology
+
+class Torus(BaseTopology):
+    description='Torus'
+
+    def __init__(self, controllers):
+        self.nodes = controllers
+
+    # Makes a generic torus assuming an equal number of cache and directory cntrls
+    # Assuming a folded-torus on-chip layout (as shown on gem5 wiki).
+    # All links (including the wrap-around ones) are of equal length, double that
+    # of a mesh. Thus, each link is assigned a latency of 2 cycles.
+
+    def makeTopology(self, options, IntLink, ExtLink, Router):
+        nodes = self.nodes
+
+        num_routers = options.num_cpus
+        num_rows = options.mesh_rows
+
+        # There must be an evenly divisible number of cntrls to routers
+        # Also, obviously the number or rows must be <= the number of routers
+        cntrls_per_router, remainder = divmod(len(nodes), num_routers)
+        assert(num_rows <= num_routers)
+        num_columns = int(num_routers / num_rows)
+        assert(num_columns * num_rows == num_routers)
+
+        # Create the routers in the torus
+        routers = [Router(router_id=i) for i in range(num_routers)]
+
+        # link counter to set unique link ids
+        link_count = 0
+
+        # Add all but the remainder nodes to the list of nodes to be uniformly
+        # distributed across the network.
+        network_nodes = []
+        remainder_nodes = []
+        for node_index in xrange(len(nodes)):
+            if node_index < (len(nodes) - remainder):
+                network_nodes.append(nodes[node_index])
+            else:
+                remainder_nodes.append(nodes[node_index])
+
+        # Connect each node to the appropriate router
+        ext_links = []
+        for (i, n) in enumerate(network_nodes):
+            cntrl_level, router_id = divmod(i, num_routers)
+            assert(cntrl_level < cntrls_per_router)
+            ext_links.append(ExtLink(link_id=link_count, ext_node=n,
+                                    int_node=routers[router_id]))
+            link_count += 1
+
+        # Connect the remainding nodes to router 0.  These should only be
+        # DMA nodes.
+        for (i, node) in enumerate(remainder_nodes):
+            assert(node.type == 'DMA_Controller')
+            assert(i < remainder)
+            ext_links.append(ExtLink(link_id=link_count, ext_node=node,
+                                    int_node=routers[0]))
+            link_count += 1
+
+        # Create the torus links.  First row (east-west) links then column
+        # (north-south) links
+        # column links are given higher weights to implement XY routing
+        int_links = []
+        for row in xrange(num_rows):
+            for col in xrange(num_columns):
+                west_id = col + (row * num_columns)
+                if (col + 1 < num_columns):
+                    east_id = (col + 1) + (row * num_columns)
+                else:
+                    east_id = (row * num_columns)
+                int_links.append(IntLink(link_id=link_count,
+                                        node_a=routers[east_id],
+                                        node_b=routers[west_id],
+                                        latency=2,
+                                        weight=1))
+                link_count += 1
+
+        for col in xrange(num_columns):
+            for row in xrange(num_rows):
+                north_id = col + (row * num_columns)
+                if (row + 1 < num_rows):
+                    south_id = col + ((row + 1) * num_columns)
+                else:
+                    south_id = col
+                int_links.append(IntLink(link_id=link_count,
+                                        node_a=routers[north_id],
+                                        node_b=routers[south_id],
+                                        latency=2,
+                                        weight=2))
+                link_count += 1
+
+        return routers, int_links, ext_links