From 100cbc9cf63af46697f129c9c10f0cc80ff7db9d Mon Sep 17 00:00:00 2001 From: Erfan Azarkhish Date: Tue, 3 Nov 2015 12:17:56 -0600 Subject: [PATCH] mem: hmc: top level design This patch enables modeling a complete Hybrid Memory Cube (HMC) device. It highly reuses the existing components in gem5's general memory system with some small modifications. This changeset requires additional patches to model a complete HMC device. Committed by: Nilay Vaish --- configs/common/HMC.py | 238 ++++++++++++++++++++++++++++++++++++ configs/common/MemConfig.py | 21 +++- configs/example/fs.py | 1 + 3 files changed, 254 insertions(+), 6 deletions(-) create mode 100644 configs/common/HMC.py diff --git a/configs/common/HMC.py b/configs/common/HMC.py new file mode 100644 index 000000000..8234e07c4 --- /dev/null +++ b/configs/common/HMC.py @@ -0,0 +1,238 @@ +# 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 + +# 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 +# +# 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: +# SerialLink is a simple variation of the Bridge class, with the ability to +# account for the latency of packet serialization. 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. Instead bandwidth/port of the HMCController has been adjusted to +# reflect the bandwidth delivered by 1 serial link. +# +# - HMC CONTROLLER: +# Contains a large buffer (modeled with Bridge) to hide the access latency +# of the memory cube. Plus it simply forwards the packets to the serial +# links in a round-robin fashion to balance load among them. +# * 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. + +import optparse + +import m5 +from m5.objects import * + +# A single Hybrid Memory Cube (HMC) +class HMCSystem(SimOject): + + #*****************************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") + + #*****************************SERIAL LINK PARAMETERS********************** + # Number of serial links [1] + num_serial_links = 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( 16, "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( 16, "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") + + # Header overhead of the serial links: Header size is 128bits in HMC [1], + # and we have 16 lanes, so the overhead is 8 cycles + link_overhead = Param.Cycles(8, "The number of cycles required to" + " transmit the packet header over the serial link") + + # Clock frequency of the serial links [1] + link_frequency = Param.Frequency('10GHz', "Clock Frequency of the serial" + "links") + + # 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") + + #*****************************HMC CONTROLLER PARAMETERS******************* + # Number of packets (not flits) to store at the HMC controller. This + # number should be high enough to be able to hide the high latency of HMC + ctrl_buffer_size_req = Param.Unsigned( 256, "Number of packets to buffer " + "at the HMC controller (request side)") + + # Number of packets (not flits) to store at the response side of the HMC + # controller. + ctrl_buffer_size_rsp = Param.Unsigned( 256, "Number of packets to buffer " + "at the HMC controller (response side)") + + # Latency of the HMC controller to process the packets + # (ClockDomain = Host clock domain) + ctrl_latency = Param.Cycles(4, "The number of cycles required for the " + " controller to process the packet") + + # Wiring latency from the SoC crossbar to the HMC controller + ctrl_static_latency = Param.Latency('500ps', "Static latency of the HMC" + "controller") + + #*****************************PERFORMANCE MONITORING********************** + # The main monitor behind the HMC Controller + enable_global_monitor = Param.Bool(True, "The main monitor behind the " + "HMC Controller") + + # The link performance monitors + enable_link_monitor = Param.Bool(True, "The link monitors" ) + +# Create an HMC device and attach it to the current system +def config_hmc(options, system): + + system.hmc=HMCSystem() + + system.buffer = Bridge(ranges=system.mem_ranges, + req_size=system.hmc.ctrl_buffer_size_req, + resp_size=system.hmc.ctrl_buffer_size_rsp, + delay=system.hmc.ctrl_static_latency) + try: + system.hmc.enable_global_monitor = options.enable_global_monitor + except: + pass; + + try: + system.hmc.enable_link_monitor = options.enable_link_monitor + except: + pass; + + system.membus.master = system.buffer.slave + + # The HMC controller (Clock domain is the same as the host) + system.hmccontroller = HMCController(width=(system.hmc.num_lanes_per_link. + value * system.hmc.num_serial_links/8), + frontend_latency=system.hmc.ctrl_latency, + forward_latency=system.hmc.link_overhead, + response_latency=system.hmc.link_overhead) + + system.hmccontroller.clk_domain = SrcClockDomain(clock=system.hmc. + link_frequency, voltage_domain = VoltageDomain(voltage = '1V')) + + # Serial Links + system.hmc.seriallink =[ SerialLink(ranges = system.mem_ranges, + req_size=system.hmc.link_buffer_size_req, + resp_size=system.hmc.link_buffer_size_rsp, + num_lanes=system.hmc.num_lanes_per_link, + delay=system.hmc.link_latency) + for i in xrange(system.hmc.num_serial_links)] + + if system.hmc.enable_link_monitor: + system.hmc.lmonitor = [ CommMonitor() + for i in xrange(system.hmc.num_serial_links)] + + # The HMC Crossbar located in its logic-base (LoB) + system.hmc.xbar = NoncoherentXBar(width = system.hmc.xbar_width, + frontend_latency=system.hmc.xbar_frontend_latency, + forward_latency=system.hmc.xbar_forward_latency, + response_latency=system.hmc.xbar_response_latency ) + system.hmc.xbar.clk_domain = SrcClockDomain(clock = + system.hmc.xbar_frequency, voltage_domain = + VoltageDomain(voltage = '1V')) + + if system.hmc.enable_global_monitor: + system.gmonitor = CommMonitor() + system.buffer.master = system.gmonitor.slave + system.gmonitor.master = system.hmccontroller.slave + else: + system.hmccontroller.slave = system.buffer.master + + for i in xrange(system.hmc.num_serial_links): + system.hmccontroller.master = system.hmc.seriallink[i].slave + system.hmc.seriallink[i].clk_domain = system.hmccontroller.clk_domain; + if system.hmc.enable_link_monitor: + system.hmc.seriallink[i].master = system.hmc.lmonitor[i].slave + system.hmc.lmonitor[i].master = system.hmc.xbar.slave + else: + system.hmc.seriallink[i].master = system.hmc.xbar.slave diff --git a/configs/common/MemConfig.py b/configs/common/MemConfig.py index 0191554a7..286898798 100644 --- a/configs/common/MemConfig.py +++ b/configs/common/MemConfig.py @@ -39,6 +39,7 @@ import m5.objects import inspect import sys +import HMC from textwrap import TextWrapper # Dictionary of mapping names of real memory controller models to @@ -151,6 +152,14 @@ def config_mem(options, system): them. """ + if ( options.mem_type == "HMC_2500_x32"): + HMC.config_hmc(options, system) + subsystem = system.hmc + xbar = system.hmc.xbar + else: + subsystem = system + xbar = system.membus + if options.tlm_memory: system.external_memory = m5.objects.ExternalSlave( port_type="tlm", @@ -161,11 +170,11 @@ def config_mem(options, system): return if options.external_memory_system: - system.external_memory = m5.objects.ExternalSlave( + subsystem.external_memory = m5.objects.ExternalSlave( port_type=options.external_memory_system, - port_data="init_mem0", port=system.membus.master, + port_data="init_mem0", port=xbar.master, addr_ranges=system.mem_ranges) - system.kernel_addr_check = False + subsystem.kernel_addr_check = False return nbr_mem_ctrls = options.mem_channels @@ -199,8 +208,8 @@ def config_mem(options, system): mem_ctrls.append(mem_ctrl) - system.mem_ctrls = mem_ctrls + subsystem.mem_ctrls = mem_ctrls # Connect the controllers to the membus - for i in xrange(len(system.mem_ctrls)): - system.mem_ctrls[i].port = system.membus.master + for i in xrange(len(subsystem.mem_ctrls)): + subsystem.mem_ctrls[i].port = xbar.master diff --git a/configs/example/fs.py b/configs/example/fs.py index 9d8b87aaa..69b2e970a 100644 --- a/configs/example/fs.py +++ b/configs/example/fs.py @@ -215,6 +215,7 @@ def build_test_system(np): test_sys.cpu[i].createThreads() CacheConfig.config_cache(options, test_sys) + MemConfig.config_mem(options, test_sys) return test_sys -- 2.30.2