# Copyright (c) 2010 Advanced Micro Devices, Inc.
# 2016 Georgia 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 SimpleTopology
# Creates a generic Mesh assuming an equal number of cache
# and directory controllers.
# West-first routing is enforced (using link weights)
# to guarantee deadlock freedom.
# The network randomly chooses between links with the same
# weight for messages within unordered virtual networks.
# Within ordered virtual networks, a fixed link direction
# is always chosen based on which appears first inside the
# routing table.
class Mesh_westfirst(SimpleTopology):
description='Mesh_westfirst'
def __init__(self, controllers):
self.nodes = controllers
# Makes a generic mesh
# assuming an equal number of cache and directory cntrls
def makeTopology(self, options, network, IntLink, ExtLink, Router):
nodes = self.nodes
num_routers = options.num_cpus
num_rows = options.mesh_rows
# default values for link latency and router latency.
# Can be over-ridden on a per link/router basis
link_latency = options.link_latency # used by simple and garnet
router_latency = options.router_latency # only used by garnet
# 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 > 0 and 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, latency=router_latency) \
for i in range(num_routers)]
network.routers = 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],
latency = link_latency))
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],
latency = link_latency))
link_count += 1
network.ext_links = ext_links
# Create the mesh links.
int_links = []
# East output to West input links (weight = 2)
for row in xrange(num_rows):
for col in xrange(num_columns):
if (col + 1 < num_columns):
east_out = col + (row * num_columns)
west_in = (col + 1) + (row * num_columns)
int_links.append(IntLink(link_id=link_count,
src_node=routers[east_out],
dst_node=routers[west_in],
latency = link_latency,
weight=2))
link_count += 1
# West output to East input links (weight = 1)
for row in xrange(num_rows):
for col in xrange(num_columns):
if (col + 1 < num_columns):
east_in = col + (row * num_columns)
west_out = (col + 1) + (row * num_columns)
int_links.append(IntLink(link_id=link_count,
src_node=routers[west_out],
dst_node=routers[east_in],
latency = link_latency,
weight=1))
link_count += 1
# North output to South input links (weight = 2)
for col in xrange(num_columns):
for row in xrange(num_rows):
if (row + 1 < num_rows):
north_out = col + (row * num_columns)
south_in = col + ((row + 1) * num_columns)
int_links.append(IntLink(link_id=link_count,
src_node=routers[north_out],
dst_node=routers[south_in],
latency = link_latency,
weight=2))
link_count += 1
# South output to North input links (weight = 2)
for col in xrange(num_columns):
for row in xrange(num_rows):
if (row + 1 < num_rows):
north_in = col + (row * num_columns)
south_out = col + ((row + 1) * num_columns)
int_links.append(IntLink(link_id=link_count,
src_node=routers[south_out],
dst_node=routers[north_in],
latency = link_latency,
weight=2))
link_count += 1
network.int_links = int_links