ruby_caches_MI_example.py revision 12611:8c69b5670fbb 
1# -*- coding: utf-8 -*-
2# Copyright (c) 2015 Jason Power
3# All rights reserved.
4#
5# Redistribution and use in source and binary forms, with or without
6# modification, are permitted provided that the following conditions are
7# met: redistributions of source code must retain the above copyright
8# notice, this list of conditions and the following disclaimer;
9# redistributions in binary form must reproduce the above copyright
10# notice, this list of conditions and the following disclaimer in the
11# documentation and/or other materials provided with the distribution;
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
18# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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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25# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27#
28# Authors: Jason Power
29
30""" This file creates a set of Ruby caches, the Ruby network, and a simple
31point-to-point topology.
32See Part 3 in the Learning gem5 book: learning.gem5.org/book/part3
33You can change simple_ruby to import from this file instead of from msi_caches
34to use the MI_example protocol instead of MSI.
35
36IMPORTANT: If you modify this file, it's likely that the Learning gem5 book
37           also needs to be updated. For now, email Jason <jason@lowepower.com>
38
39"""
40
41import math
42
43from m5.defines import buildEnv
44from m5.util import fatal, panic
45
46from m5.objects import *
47
48class MyCacheSystem(RubySystem):
49
50    def __init__(self):
51        if buildEnv['PROTOCOL'] != 'MI_example':
52            fatal("This system assumes MI_example!")
53
54        super(MyCacheSystem, self).__init__()
55
56    def setup(self, system, cpus, mem_ctrls):
57        """Set up the Ruby cache subsystem. Note: This can't be done in the
58           constructor because many of these items require a pointer to the
59           ruby system (self). This causes infinite recursion in initialize()
60           if we do this in the __init__.
61        """
62        # Ruby's global network.
63        self.network = MyNetwork(self)
64
65        # MI example uses 5 virtual networks
66        self.number_of_virtual_networks = 5
67        self.network.number_of_virtual_networks = 5
68
69        # There is a single global list of all of the controllers to make it
70        # easier to connect everything to the global network. This can be
71        # customized depending on the topology/network requirements.
72        # Create one controller for each L1 cache (and the cache mem obj.)
73        # Create a single directory controller (Really the memory cntrl)
74        self.controllers = \
75            [L1Cache(system, self, cpu) for cpu in cpus] + \
76            [DirController(self, system.mem_ranges, mem_ctrls)]
77
78        # Create one sequencer per CPU. In many systems this is more
79        # complicated since you have to create sequencers for DMA controllers
80        # and other controllers, too.
81        self.sequencers = [RubySequencer(version = i,
82                                # I/D cache is combined and grab from ctrl
83                                icache = self.controllers[i].cacheMemory,
84                                dcache = self.controllers[i].cacheMemory,
85                                clk_domain = self.controllers[i].clk_domain,
86                                ) for i in range(len(cpus))]
87
88        for i,c in enumerate(self.controllers[0:len(cpus)]):
89            c.sequencer = self.sequencers[i]
90
91        self.num_of_sequencers = len(self.sequencers)
92
93        # Create the network and connect the controllers.
94        # NOTE: This is quite different if using Garnet!
95        self.network.connectControllers(self.controllers)
96        self.network.setup_buffers()
97
98        # Set up a proxy port for the system_port. Used for load binaries and
99        # other functional-only things.
100        self.sys_port_proxy = RubyPortProxy()
101        system.system_port = self.sys_port_proxy.slave
102
103        # Connect the cpu's cache, interrupt, and TLB ports to Ruby
104        for i,cpu in enumerate(cpus):
105            cpu.icache_port = self.sequencers[i].slave
106            cpu.dcache_port = self.sequencers[i].slave
107            isa = buildEnv['TARGET_ISA']
108            if isa == 'x86':
109                cpu.interrupts[0].pio = self.sequencers[i].master
110                cpu.interrupts[0].int_master = self.sequencers[i].slave
111                cpu.interrupts[0].int_slave = self.sequencers[i].master
112            if isa == 'x86' or isa == 'arm':
113                cpu.itb.walker.port = self.sequencers[i].slave
114                cpu.dtb.walker.port = self.sequencers[i].slave
115
116class L1Cache(L1Cache_Controller):
117
118    _version = 0
119    @classmethod
120    def versionCount(cls):
121        cls._version += 1 # Use count for this particular type
122        return cls._version - 1
123
124    def __init__(self, system, ruby_system, cpu):
125        """CPUs are needed to grab the clock domain and system is needed for
126           the cache block size.
127        """
128        super(L1Cache, self).__init__()
129
130        self.version = self.versionCount()
131        # This is the cache memory object that stores the cache data and tags
132        self.cacheMemory = RubyCache(size = '16kB',
133                               assoc = 8,
134                               start_index_bit = self.getBlockSizeBits(system))
135        self.clk_domain = cpu.clk_domain
136        self.send_evictions = self.sendEvicts(cpu)
137        self.ruby_system = ruby_system
138        self.connectQueues(ruby_system)
139
140    def getBlockSizeBits(self, system):
141        bits = int(math.log(system.cache_line_size, 2))
142        if 2**bits != system.cache_line_size.value:
143            panic("Cache line size not a power of 2!")
144        return bits
145
146    def sendEvicts(self, cpu):
147        """True if the CPU model or ISA requires sending evictions from caches
148           to the CPU. Two scenarios warrant forwarding evictions to the CPU:
149           1. The O3 model must keep the LSQ coherent with the caches
150           2. The x86 mwait instruction is built on top of coherence
151           3. The local exclusive monitor in ARM systems
152        """
153        if type(cpu) is DerivO3CPU or \
154           buildEnv['TARGET_ISA'] in ('x86', 'arm'):
155            return True
156        return False
157
158    def connectQueues(self, ruby_system):
159        """Connect all of the queues for this controller.
160        """
161        self.mandatoryQueue = MessageBuffer()
162        self.requestFromCache = MessageBuffer(ordered = True)
163        self.requestFromCache.master = ruby_system.network.slave
164        self.responseFromCache = MessageBuffer(ordered = True)
165        self.responseFromCache.master = ruby_system.network.slave
166        self.forwardToCache = MessageBuffer(ordered = True)
167        self.forwardToCache.slave = ruby_system.network.master
168        self.responseToCache = MessageBuffer(ordered = True)
169        self.responseToCache.slave = ruby_system.network.master
170
171class DirController(Directory_Controller):
172
173    _version = 0
174    @classmethod
175    def versionCount(cls):
176        cls._version += 1 # Use count for this particular type
177        return cls._version - 1
178
179    def __init__(self, ruby_system, ranges, mem_ctrls):
180        """ranges are the memory ranges assigned to this controller.
181        """
182        if len(mem_ctrls) > 1:
183            panic("This cache system can only be connected to one mem ctrl")
184        super(DirController, self).__init__()
185        self.version = self.versionCount()
186        self.addr_ranges = ranges
187        self.ruby_system = ruby_system
188        self.directory = RubyDirectoryMemory()
189        # Connect this directory to the memory side.
190        self.memory = mem_ctrls[0].port
191        self.connectQueues(ruby_system)
192
193    def connectQueues(self, ruby_system):
194        self.requestToDir = MessageBuffer(ordered = True)
195        self.requestToDir.slave = ruby_system.network.master
196        self.dmaRequestToDir = MessageBuffer(ordered = True)
197        self.dmaRequestToDir.slave = ruby_system.network.master
198
199        self.responseFromDir = MessageBuffer()
200        self.responseFromDir.master = ruby_system.network.slave
201        self.dmaResponseFromDir = MessageBuffer(ordered = True)
202        self.dmaResponseFromDir.master = ruby_system.network.slave
203        self.forwardFromDir = MessageBuffer()
204        self.forwardFromDir.master = ruby_system.network.slave
205        self.responseFromMemory = MessageBuffer()
206
207class MyNetwork(SimpleNetwork):
208    """A simple point-to-point network. This doesn't not use garnet.
209    """
210
211    def __init__(self, ruby_system):
212        super(MyNetwork, self).__init__()
213        self.netifs = []
214        self.ruby_system = ruby_system
215
216    def connectControllers(self, controllers):
217        """Connect all of the controllers to routers and connec the routers
218           together in a point-to-point network.
219        """
220        # Create one router/switch per controller in the system
221        self.routers = [Switch(router_id = i) for i in range(len(controllers))]
222
223        # Make a link from each controller to the router. The link goes
224        # externally to the network.
225        self.ext_links = [SimpleExtLink(link_id=i, ext_node=c,
226                                        int_node=self.routers[i])
227                          for i, c in enumerate(controllers)]
228
229        # Make an "internal" link (internal to the network) between every pair
230        # of routers.
231        link_count = 0
232        self.int_links = []
233        for ri in self.routers:
234            for rj in self.routers:
235                if ri == rj: continue # Don't connect a router to itself!
236                link_count += 1
237                self.int_links.append(SimpleIntLink(link_id = link_count,
238                                                    src_node = ri,
239                                                    dst_node = rj))
240