1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
|
# Copyright (c) 2012-2013 ARM Limited
# All rights reserved.
#
# The license below extends only to copyright in the software and shall
# not be construed as granting a license to any other intellectual
# property including but not limited to intellectual property relating
# to a hardware implementation of the functionality of the software
# licensed hereunder. You may use the software subject to the license
# terms below provided that you ensure that this notice is replicated
# unmodified and in its entirety in all distributions of the software,
# modified or unmodified, in source code or in binary form.
#
# Copyright (c) 2015 The University of Bologna
# 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: Erfan Azarkhish
# Abdul Mutaal Ahmad
# A Simplified model of a complete HMC device. Based on:
# [1] http://www.hybridmemorycube.org/specification-download/
# [2] High performance AXI-4.0 based interconnect for extensible smart memory
# cubes(E. Azarkhish et. al)
# [3] Low-Power Hybrid Memory Cubes With Link Power Management and Two-Level
# Prefetching (J. Ahn et. al)
# [4] Memory-centric system interconnect design with Hybrid Memory Cubes
# (G. Kim et. al)
# [5] Near Data Processing, Are we there yet? (M. Gokhale)
# http://www.cs.utah.edu/wondp/gokhale.pdf
# [6] openHMC - A Configurable Open-Source Hybrid Memory Cube Controller
# (J. Schmidt)
# [7] Hybrid Memory Cube performance characterization on data-centric
# workloads (M. Gokhale)
#
# This script builds a complete HMC device composed of vault controllers,
# serial links, the main internal crossbar, and an external hmc controller.
#
# - VAULT CONTROLLERS:
# Instances of the HMC_2500_x32 class with their functionality specified in
# dram_ctrl.cc
#
# - THE MAIN XBAR:
# This component is simply an instance of the NoncoherentXBar class, and its
# parameters are tuned to [2].
#
# - SERIAL LINKS CONTROLLER:
# SerialLink is a simple variation of the Bridge class, with the ability to
# account for the latency of packet serialization and controller latency. We
# assume that the serializer component at the transmitter side does not need
# to receive the whole packet to start the serialization. But the
# deserializer waits for the complete packet to check its integrity first.
#
# * Bandwidth of the serial links is not modeled in the SerialLink component
# itself.
#
# * Latency of serial link controller is composed of SerDes latency + link
# controller
#
# * It is inferred from the standard [1] and the literature [3] that serial
# links share the same address range and packets can travel over any of
# them so a load distribution mechanism is required among them.
#
# -----------------------------------------
# | Host/HMC Controller |
# | ---------------------- |
# | | Link Aggregator | opt |
# | ---------------------- |
# | ---------------------- |
# | | Serial Link + Ser | * 4 |
# | ---------------------- |
# |---------------------------------------
# -----------------------------------------
# | Device
# | ---------------------- |
# | | Xbar | * 4 |
# | ---------------------- |
# | ---------------------- |
# | | Vault Controller | * 16 |
# | ---------------------- |
# | ---------------------- |
# | | Memory | |
# | ---------------------- |
# |---------------------------------------|
#
# In this version we have present 3 different HMC archiecture along with
# alongwith their corresponding test script.
#
# same: It has 4 crossbars in HMC memory. All the crossbars are connected
# to each other, providing complete memory range. This archicture also covers
# the added latency for sending a request to non-local vault(bridge in b/t
# crossbars). All the 4 serial links can access complete memory. So each
# link can be connected to separate processor.
#
# distributed: It has 4 crossbars inside the HMC. Crossbars are not
# connected.Through each crossbar only local vaults can be accessed. But to
# support this architecture we need a crossbar between serial links and
# processor.
#
# mixed: This is a hybrid architecture. It has 4 crossbars inside the HMC.
# 2 Crossbars are connected to only local vaults. From other 2 crossbar, a
# request can be forwarded to any other vault.
import optparse
import m5
from m5.objects import *
# A single Hybrid Memory Cube (HMC)
class HMCSystem(SubSystem):
#*****************************CROSSBAR PARAMETERS*************************
# Flit size of the main interconnect [1]
xbar_width = Param.Unsigned(32, "Data width of the main XBar (Bytes)")
# Clock frequency of the main interconnect [1]
# This crossbar, is placed on the logic-based of the HMC and it has its
# own voltage and clock domains, different from the DRAM dies or from the
# host.
xbar_frequency = Param.Frequency('1GHz', "Clock Frequency of the main "
"XBar")
# Arbitration latency of the HMC XBar [1]
xbar_frontend_latency = Param.Cycles(1, "Arbitration latency of the XBar")
# Latency to forward a packet via the interconnect [1](two levels of FIFOs
# at the input and output of the inteconnect)
xbar_forward_latency = Param.Cycles(2, "Forward latency of the XBar")
# Latency to forward a response via the interconnect [1](two levels of
# FIFOs at the input and output of the inteconnect)
xbar_response_latency = Param.Cycles(2, "Response latency of the XBar")
# number of cross which connects 16 Vaults to serial link[7]
number_mem_crossbar = Param.Unsigned(4, "Number of crossbar in HMC"
)
#*****************************SERIAL LINK PARAMETERS***********************
# Number of serial links controllers [1]
num_links_controllers = Param.Unsigned(4, "Number of serial links")
# Number of packets (not flits) to store at the request side of the serial
# link. This number should be adjusted to achive required bandwidth
link_buffer_size_req = Param.Unsigned(10, "Number of packets to buffer "
"at the request side of the serial link")
# Number of packets (not flits) to store at the response side of the serial
# link. This number should be adjusted to achive required bandwidth
link_buffer_size_rsp = Param.Unsigned(10, "Number of packets to buffer "
"at the response side of the serial link")
# Latency of the serial link composed by SER/DES latency (1.6ns [4]) plus
# the PCB trace latency (3ns Estimated based on [5])
link_latency = Param.Latency('4.6ns', "Latency of the serial links")
# Clock frequency of the each serial link(SerDes) [1]
link_frequency = Param.Frequency('10GHz', "Clock Frequency of the serial"
"links")
# Clock frequency of serial link Controller[6]
# clk_hmc[Mhz]= num_lanes_per_link * lane_speed [Gbits/s] /
# data_path_width * 10^6
# clk_hmc[Mhz]= 16 * 10 Gbps / 256 * 10^6 = 625 Mhz
link_controller_frequency = Param.Frequency('625MHz',
"Clock Frequency of the link controller")
# Latency of the serial link controller to process the packets[1][6]
# (ClockDomain = 625 Mhz )
# used here for calculations only
link_ctrl_latency = Param.Cycles(4, "The number of cycles required for the"
"controller to process the packet")
# total_ctrl_latency = link_ctrl_latency + link_latency
# total_ctrl_latency = 4(Cycles) * 1.6 ns + 4.6 ns
total_ctrl_latency = Param.Latency('11ns', "The latency experienced by"
"every packet regardless of size of packet")
# Number of parallel lanes in each serial link [1]
num_lanes_per_link = Param.Unsigned( 16, "Number of lanes per each link")
# Number of serial links [1]
num_serial_links = Param.Unsigned(4, "Number of serial links")
# speed of each lane of serial link - SerDes serial interface 10 Gb/s
serial_link_speed = Param.UInt64(10, "Gbs/s speed of each lane of"
"serial link")
#*****************************PERFORMANCE MONITORING************************
# The main monitor behind the HMC Controller
enable_global_monitor = Param.Bool(False, "The main monitor behind the "
"HMC Controller")
# The link performance monitors
enable_link_monitor = Param.Bool(False, "The link monitors" )
# link aggregator enable - put a cross between buffers & links
enable_link_aggr = Param.Bool(False, "The crossbar between port and "
"Link Controller")
enable_buff_div = Param.Bool(True, "Memory Range of Buffer is"
"divided between total range")
#*****************************HMC ARCHITECTURE ************************
# Memory chunk for 16 vault - numbers of vault / number of crossbars
mem_chunk = Param.Unsigned(4, "Chunk of memory range for each cross bar "
"in arch 0")
# size of req buffer within crossbar, used for modelling extra latency
# when the reuqest go to non-local vault
xbar_buffer_size_req = Param.Unsigned(10, "Number of packets to buffer "
"at the request side of the crossbar")
# size of response buffer within crossbar, used for modelling extra latency
# when the response received from non-local vault
xbar_buffer_size_resp = Param.Unsigned(10, "Number of packets to buffer "
"at the response side of the crossbar")
# configure host system with Serial Links
def config_host_hmc(options, system):
system.hmc_host=HMCSystem()
try:
system.hmc_host.enable_global_monitor = options.enable_global_monitor
except:
pass;
try:
system.hmc_host.enable_link_monitor = options.enable_link_monitor
except:
pass;
# Serial link Controller with 16 SerDes links at 10 Gbps
# with serial link ranges w.r.t to architecture
system.hmc_host.seriallink = [SerialLink(ranges = options.ser_ranges[i],
req_size=system.hmc_host.link_buffer_size_req,
resp_size=system.hmc_host.link_buffer_size_rsp,
num_lanes=system.hmc_host.num_lanes_per_link,
link_speed=system.hmc_host.serial_link_speed,
delay=system.hmc_host.total_ctrl_latency)
for i in xrange(system.hmc_host.num_serial_links)]
# enable global monitor
if system.hmc_host.enable_global_monitor:
system.hmc_host.lmonitor = [ CommMonitor()
for i in xrange(system.hmc_host.num_serial_links)]
# set the clock frequency for serial link
for i in xrange(system.hmc_host.num_serial_links):
system.hmc_host.seriallink[i].clk_domain = SrcClockDomain(clock=system.
hmc_host.link_controller_frequency, voltage_domain=
VoltageDomain(voltage = '1V'))
# Connect membus/traffic gen to Serial Link Controller for differrent HMC
# architectures
if options.arch == "distributed":
for i in xrange(system.hmc_host.num_links_controllers):
if system.hmc_host.enable_global_monitor:
system.membus.master = system.hmc_host.lmonitor[i].slave
system.hmc_host.lmonitor[i].master = \
system.hmc_host.seriallink[i].slave
else:
system.membus.master = system.hmc_host.seriallink[i].slave
if options.arch == "mixed":
if system.hmc_host.enable_global_monitor:
system.membus.master = system.hmc_host.lmonitor[0].slave
system.hmc_host.lmonitor[0].master = \
system.hmc_host.seriallink[0].slave
system.membus.master = system.hmc_host.lmonitor[1].slave
system.hmc_host.lmonitor[1].master = \
system.hmc_host.seriallink[1].slave
system.tgen[2].port = system.hmc_host.lmonitor[2].slave
system.hmc_host.lmonitor[2].master = \
system.hmc_host.seriallink[2].slave
system.tgen[3].port = system.hmc_host.lmonitor[3].slave
system.hmc_host.lmonitor[3].master = \
system.hmc_host.seriallink[3].slave
else:
system.membus.master = system.hmc_host.seriallink[0].slave
system.membus.master = system.hmc_host.seriallink[1].slave
system.tgen[2].port = system.hmc_host.seriallink[2].slave
system.tgen[3].port = system.hmc_host.seriallink[3].slave
if options.arch == "same" :
for i in xrange(system.hmc_host.num_links_controllers):
if system.hmc_host.enable_global_monitor:
system.tgen[i].port = system.hmc_host.lmonitor[i].slave
system.hmc_host.lmonitor[i].master = \
system.hmc_host.seriallink[i].slave
else:
system.tgen[i].port = system.hmc_host.seriallink[i].slave
return system
# Create an HMC device and attach it to the current system
def config_hmc(options, system, hmc_host):
# Create HMC device
system.hmc_dev = HMCSystem()
# Global monitor
try:
system.hmc_dev.enable_global_monitor = options.enable_global_monitor
except:
pass;
try:
system.hmc_dev.enable_link_monitor = options.enable_link_monitor
except:
pass;
if system.hmc_dev.enable_link_monitor:
system.hmc_dev.lmonitor = [ CommMonitor()
for i in xrange(system.hmc_dev.num_links_controllers)]
# 4 HMC Crossbars located in its logic-base (LoB)
system.hmc_dev.xbar = [ NoncoherentXBar(width=system.hmc_dev.xbar_width,
frontend_latency=system.hmc_dev.xbar_frontend_latency,
forward_latency=system.hmc_dev.xbar_forward_latency,
response_latency=system.hmc_dev.xbar_response_latency )
for i in xrange(system.hmc_host.number_mem_crossbar)]
for i in xrange(system.hmc_dev.number_mem_crossbar):
system.hmc_dev.xbar[i].clk_domain = SrcClockDomain(
clock=system.hmc_dev.xbar_frequency,voltage_domain=
VoltageDomain(voltage='1V'))
# Attach 4 serial link to 4 crossbar/s
for i in xrange(system.hmc_dev.num_serial_links):
if system.hmc_dev.enable_link_monitor:
system.hmc_host.seriallink[i].master = \
system.hmc_dev.lmonitor[i].slave
system.hmc_dev.lmonitor[i].master = system.hmc_dev.xbar[i].slave
else:
system.hmc_host.seriallink[i].master = system.hmc_dev.xbar[i].slave
# Connecting xbar with each other for request arriving at the wrong xbar,
# then it will be forward to correct xbar. Bridge is used to connect xbars
if options.arch == "same":
numx = len(system.hmc_dev.xbar)
# create a list of buffers
system.hmc_dev.buffers = [ Bridge(
req_size=system.hmc_dev.xbar_buffer_size_req,
resp_size=system.hmc_dev.xbar_buffer_size_resp)
for i in xrange(numx * (system.hmc_dev.mem_chunk - 1))]
# Buffer iterator
it = iter(range(len(system.hmc_dev.buffers)))
# necesarry to add system_port to one of the xbar
system.system_port = system.hmc_dev.xbar[3].slave
# iterate over all the crossbars and connect them as required
for i in range(numx):
for j in range(numx):
# connect xbar to all other xbars except itself
if i != j:
# get the next index of buffer
index = it.next()
# Change the default values for ranges of bridge
system.hmc_dev.buffers[index].ranges = system.mem_ranges[
j * int(system.hmc_dev.mem_chunk):
(j + 1) * int(system.hmc_dev.mem_chunk)]
# Connect the bridge between corssbars
system.hmc_dev.xbar[i].master = system.hmc_dev.buffers[
index].slave
system.hmc_dev.buffers[
index].master = system.hmc_dev.xbar[j].slave
else:
# Don't connect the xbar to itself
pass
# Two crossbars are connected to all other crossbars-Other 2 vault
# can only direct traffic to it local vaults
if options.arch == "mixed":
system.hmc_dev.buffer30 = Bridge(ranges=system.mem_ranges[0:4])
system.hmc_dev.xbar[3].master = system.hmc_dev.buffer30.slave
system.hmc_dev.buffer30.master = system.hmc_dev.xbar[0].slave
system.hmc_dev.buffer31 = Bridge(ranges=system.mem_ranges[4:8])
system.hmc_dev.xbar[3].master = system.hmc_dev.buffer31.slave
system.hmc_dev.buffer31.master = system.hmc_dev.xbar[1].slave
system.hmc_dev.buffer32 = Bridge(ranges=system.mem_ranges[8:12])
system.hmc_dev.xbar[3].master = system.hmc_dev.buffer32.slave
system.hmc_dev.buffer32.master = system.hmc_dev.xbar[2].slave
system.hmc_dev.buffer20 = Bridge(ranges=system.mem_ranges[0:4])
system.hmc_dev.xbar[2].master = system.hmc_dev.buffer20.slave
system.hmc_dev.buffer20.master = system.hmc_dev.xbar[0].slave
system.hmc_dev.buffer21 = Bridge(ranges=system.mem_ranges[4:8])
system.hmc_dev.xbar[2].master = system.hmc_dev.buffer21.slave
system.hmc_dev.buffer21.master = system.hmc_dev.xbar[1].slave
system.hmc_dev.buffer23 = Bridge(ranges=system.mem_ranges[12:16])
system.hmc_dev.xbar[2].master = system.hmc_dev.buffer23.slave
system.hmc_dev.buffer23.master = system.hmc_dev.xbar[3].slave
|