configs: Add example memory traffic runscript

This simple example shows how to use the test board to test the
bandwidth for an HBM2 pair of pseudo channels

Change-Id: I6235d0cb11909f5b4cc6442e419496c77425ba37
Signed-off-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/64018
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>

configs/example/gem5_library/memory_traffic.py

@@ -0,0 +1,114 @@
+# Copyright (c) 2021 The Regents of the University of California
+# 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.
+
+"""
+This script is used for running a traffic generator connected to a memory
+device. It supports linear and random accesses with a configurable amount
+of write traffic.
+
+By default, this scripts runs with one channel (two pseudo channels) of HBM2
+and this channel is driven with 32GiB/s of traffic for 1ms.
+"""
+
+import argparse
+
+from m5.objects import MemorySize
+from gem5.components.boards.test_board import TestBoard
+
+from gem5.components.processors.linear_generator import LinearGenerator
+from gem5.components.processors.random_generator import RandomGenerator
+
+from gem5.components.memory.hbm import HighBandwidthMemory
+from gem5.components.memory.dram_interfaces.hbm import HBM_2000_4H_1x64
+
+from gem5.simulate.simulator import Simulator
+
+
+def generator_factory(
+    generator_class: str, rd_perc: int, mem_size: MemorySize
+):
+    rd_perc = int(rd_perc)
+    if rd_perc > 100 or rd_perc < 0:
+        raise ValueError(
+            "Read percentage has to be an integer number between 0 and 100."
+        )
+    if generator_class == "LinearGenerator":
+        return LinearGenerator(
+            duration="1ms", rate="32GiB/s", max_addr=mem_size, rd_perc=rd_perc
+        )
+    elif generator_class == "RandomGenerator":
+        return RandomGenerator(
+            duration="1ms", rate="32GiB/s", max_addr=mem_size, rd_perc=rd_perc
+        )
+    else:
+        raise ValueError(f"Unknown generator class {generator_class}")
+
+
+parser = argparse.ArgumentParser(
+    description="A traffic generator that can be used to test a gem5 "
+    "memory component."
+)
+
+parser.add_argument(
+    "generator_class",
+    type=str,
+    help="The class of generator to use.",
+    choices=[
+        "LinearGenerator",
+        "RandomGenerator",
+    ],
+)
+
+parser.add_argument(
+    "read_percentage",
+    type=int,
+    help="Percentage of read requests in the generated traffic.",
+)
+
+args = parser.parse_args()
+
+# Single pair of HBM2 pseudo channels. This can be replaced with any
+# single ported memory device
+memory = HighBandwidthMemory(HBM_2000_4H_1x64, 1, 128)
+
+generator = generator_factory(
+    args.generator_class, args.read_percentage, memory.get_size()
+)
+
+# We use the Test Board. This is a special board to run traffic generation
+# tasks. Can replace the cache_hierarchy with any hierarchy to simulate the
+# cache as well as the memory
+board = TestBoard(
+    clk_freq="1GHz",  # Ignored for these generators
+    generator=generator,  # We pass the traffic generator as the processor.
+    memory=memory,
+    # With no cache hierarchy the test board will directly connect the
+    # generator to the memory
+    cache_hierarchy=None,
+)
+
+simulator = Simulator(board=board)
+simulator.run()