This way there will always be a workload object, even if nothing needs
to be set up. This default can also be used in low_power_sweep.py,
where the workload object was just a placeholder.
This will allow required functionality like determining endianness of a
system into the workload, rather than (for instance) in the more generic
System object. This also makes accessing less essential functionality
simpler, because we don't have to detect whether the workload is there,
and can just return default, placeholder values from the StubWorkload.
Change-Id: Idfc3e75c65318d75a3eae6a19944ae1f79a2d111
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/52103
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The workload object is still optional for the sake of compatibility,
even though it probably shouldn't be in the long term. If a simulation
is just a collection of components with nothing in particular running on
it, for instance driven by a traffic generator, should it even have a
System object in the first place?
Change-Id: I8bcda72bdfa3730248226fb62f0bba9a83243d95
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/33278
Reviewed-by: Matthew Poremba <matthew.poremba@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Make the actual controller more generic
- Rename DRAMCtrl to MemCtrl
- Rename DRAMacket to MemPacket
- Rename dram_ctrl.cc to mem_ctrl.cc
- Rename dram_ctrl.hh to mem_ctrl.hh
- Create MemCtrl debug flag
Move the memory interface classes/functions to separate files
- mem_interface.cc
- mem_interface.hh
Change-Id: I1acba44c855776343e205e7733a7d8bbba92a82c
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/31654
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Made DRAMCtrl a ClockedObject, with DRAMInterface
defined as an AbstractMemory. The address
ranges are now defined per interface. Currently
the model only includes a DRAMInterface but this
can be expanded for other media types.
The controller object includes a parameter to the
interface, which is setup when gem5 is configured.
Change-Id: I6a368b845d574a713c7196c5671188ca8c1dc5e8
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/28968
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This change includes:
1) Verify available command bandwidth
2) Add support for multi-cycle commands
3) Add new timing parameters
4) Add ability to interleave bursts
5) Add LPDDR5 configurations
The DRAM controller historically does not verify contention on the
command bus and if there is adaquate command bandwidth to issue a
new command. As memory technologies evolve, multiple cycles are becoming
a requirement for some commands. Depending on the burst length, this
can stress the command bandwidth. A check was added to verify command
issue does not exceed a maximum value within a defined window. The
default window is a burst, with the maximum value defined based on the
burst length and media clocking characteristics. When the command bandwidth
is exceeded, commands will be shifted to subsequent burst windows.
Added support for multi-cycle commands, specifically Activate, which
requires a larger address width as capacities grow. Additionally,
added support for multi-cycle Read / Write bursts for low power
DRAM cases in which additional CLK synchronization may be required
to run at higher speeds.
To support emerging memories, added the following new timing parameters.
1) tPPD -- Precharge-to-Precharge delay
2) tAAD -- Max delay between Activate-1 and Activate-2 commands
I/O data rates are continuing to increase for DRAM but the core frequency
is still fairly stagnant for many technologies. As we increase the burst
length, either the core prefetch needs to increase (for a seamless burst)
or the burst will be transferred with gaps on the data bus. To support
the latter case, added the ability to interleave 2 bursts across bank
groups.
Using the changes above, added an initial set of LPDDR5 configurations.
Change-Id: I1b14fed221350e6e403f7cbf089fe6c7f033c181
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/26236
Reviewed-by: Matthew Poremba <matthew.poremba@amd.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: Gem5 Cloud Project GCB service account <345032938727@cloudbuild.gserviceaccount.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Python 2.7 used to return lists for operations such as map and range,
this has changed in Python 3. To make the configs Python 3 compliant,
add explicit conversions from iterators to lists where needed, replace
xrange with range, and fix changes to exec syntax.
This change doesn't fix import paths since that might require us to
restructure the configs slightly.
Change-Id: Idcea8482b286779fc98b4e144ca8f54069c08024
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/16002
Reviewed-by: Gabe Black <gabeblack@google.com>
This changeset updates the lat_mem_rd.py to configure the L3Cache
using the split tag_latency, data_latency parameters.
Change-Id: I8bc41d5f7664111bdda0972356d1a17762aa77e5
Reviewed-on: https://gem5-review.googlesource.com/8288
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
This patch adds two regression tests that execute the script in the
configs dir for triggering low power mode transitions. A separate
test is required for each page policy because for close-adaptive
page policy the DRAM goes into the Precharge Power-down mode while
for open-adaptive page policy it goes into the Activate Power-down
mode.
Change-Id: Iad61af23f132db046f2857cc3ef64b2bf42cf5e4
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5726
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
This change adds a Python script to sweep a few parameters with a
goal to trigger transitions to the low power states of the DRAM
controller.
This script is largely based on the sweep.py but is helpful to study
the impact of inter-transaction delay on the behaviour of the DRAM
in addition to typical sweep params like stride size, bank
utilization and read percent. An idle period is added as the last
traffic generator state to target hitting self-refresh.
Change-Id: I34380afffbf2de9f4e997dfe9fff5e615e077524
Reviewed-by: Wendy Elsasser <wendy.elsasser@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5725
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Names of DRAM configurations were updated to reflect both
the channel and device data width.
Previous naming format was:
<DEVICE_TYPE>_<DATA_RATE>_<CHANNEL_WIDTH>
The following nomenclature is now used:
<DEVICE_TYPE>_<DATA_RATE>_<n>x<w>
where n = The number of devices per rank on the channel
x = Device width
Total channel width can be calculated by n*w
Example:
A 64-bit DDR4, 2400 channel consisting of 4-bit devices:
n = 16
w = 4
The resulting configuration name is:
DDR4_2400_16x4
Updated scripts to match new naming convention.
Added unique configurations for DDR4 for:
1) 16x4
2) 8x8
3) 4x16
Change-Id: Ibd7f763b7248835c624309143cb9fc29d56a69d1
Reviewed-by: Radhika Jagtap <radhika.jagtap@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Some configuration scripts need periodic stat dumps. One of the ways
this can be achieved is by using the pariodicStatDump helper
function. This function was previously only exported in the internal
name space. Export it as a normal function in m5.stat instead.
Change-Id: Ic88bf1fd33042a62ab436d5944d8ed778264ac98
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Sascha Bischoff <sascha.bischoff@arm.com>
Continue along the same line as the recent patch that made the
Ruby-related config scripts Python packages and make also the
configs/common directory a package.
All affected config scripts are updated (hopefully).
Note that this change makes it apparent that the current organisation
and naming of the config directory and its subdirectories is rather
chaotic. We mix scripts that are directly invoked with scripts that
merely contain convenience functions. While it is not addressed in
this patch we should follow up with a re-organisation of the
config structure, and renaming of some of the packages.
Adjust the traffic generator time-out so that the script works out of
the box
Change-Id: I6b3b6b11f98b094ae3acdbe09488c26e4aeb0ab4
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
This patch adds a config script that broadly replicates the behaviour
of lat_mem_rd. The test is based on traffic generators, and as such we
simply randomise addresses in increasingly large ranges, and play them
back using the trace functionality of the traffic generator.
The test script is accompanied by a post-processing and visualisation
script. At the moment no configurability is added to tweak the memory
hierarchy, but a follow on patch could easily extend the
functionality.
This patch adds changes to the configuration scripts to support elastic
tracing and replay.
The patch adds a command line option to enable elastic tracing in SE mode
and FS mode. When enabled the Elastic Trace cpu probe is attached to O3CPU
and a few O3 CPU parameters are tuned. The Elastic Trace probe writes out
both instruction fetch and data dependency traces. The patch also enables
configuring the TraceCPU to replay traces using the SE and FS script.
The replay run is designed to resume from checkpoint using atomic cpu to
restore state keeping it consistent with FS run flow. It then switches to
TraceCPU to replay the input traces.
This patch introduces a few subclasses to the CoherentXBar and
NoncoherentXBar to distinguish the different uses in the system. We
use the crossbar in a wide range of places: interfacing cores to the
L2, as a system interconnect, connecting I/O and peripherals,
etc. Needless to say, these crossbars have very different performance,
and the clock frequency alone is not enough to distinguish these
scenarios.
Instead of trying to capture every possible case, this patch
introduces dedicated subclasses for the three primary use-cases:
L2XBar, SystemXBar and IOXbar. More can be added if needed, and the
defaults can be overridden.
This patch changes the name of the Bus classes to XBar to better
reflect the actual timing behaviour. The actual instances in the
config scripts are not renamed, and remain as e.g. iobus or membus.
As part of this renaming, the code has also been clean up slightly,
making use of range-based for loops and tidying up some comments. The
only changes outside the bus/crossbar code is due to the delay
variables in the packet.
--HG--
rename : src/mem/Bus.py => src/mem/XBar.py
rename : src/mem/coherent_bus.cc => src/mem/coherent_xbar.cc
rename : src/mem/coherent_bus.hh => src/mem/coherent_xbar.hh
rename : src/mem/noncoherent_bus.cc => src/mem/noncoherent_xbar.cc
rename : src/mem/noncoherent_bus.hh => src/mem/noncoherent_xbar.hh
rename : src/mem/bus.cc => src/mem/xbar.cc
rename : src/mem/bus.hh => src/mem/xbar.hh
Add new DRAM_ROTATE mode to traffic generator.
This mode will generate DRAM traffic that rotates across
banks per rank, command types, and ranks per channel
The looping order is illustrated below:
for (ranks per channel)
for (command types)
for (banks per rank)
// Generate DRAM Command Series
This patch also adds the read percentage as an input argument to the
DRAM sweep script. If the simulated read percentage is 0 or 100, the
middle for loop does not generate additional commands. This loop is
used only when the read percentage is set to 50, in which case the
middle loop will toggle between read and write commands.
Modified sweep.py script, which generates DRAM traffic.
Added input arguments and support for new DRAM_ROTATE mode.
The script now has input arguments for:
1) Read percentage
2) Number of ranks
3) Address mapping
4) Traffic generator mode (DRAM or DRAM_ROTATE)
The default values are:
100% reads, 1 rank, RoRaBaCoCh address mapping, and DRAM traffic gen mode
For the DRAM traffic mode, added multi-rank support.
This patch adds basic functionality to quickly visualise the output
from the DRAM efficiency script. There are some unfortunate hacks
needed to communicate the needed information from one script to the
other, and we fall back on (ab)using the simout to do this.
As part of this patch we also trim the efficiency sweep to stop at 512
bytes as this should be sufficient for all forseeable DRAMs.
This patch bumps the bus clock speed such that the interconnect does
not become a bottleneck with a DDR4-2400-x64 DRAM delivering 19.2
GByte/s theoretical max.
This patch renames the not-so-simple SimpleDRAM to a more suitable
DRAMCtrl. The name change is intended to ensure that we do not send
the wrong message (although the "simple" in SimpleDRAM was originally
intended as in cleverly simple, or elegant).
As the DRAM controller modelling work is being presented at ISPASS'14
our hope is that a broader audience will use the model in the future.
--HG--
rename : src/mem/SimpleDRAM.py => src/mem/DRAMCtrl.py
rename : src/mem/simple_dram.cc => src/mem/dram_ctrl.cc
rename : src/mem/simple_dram.hh => src/mem/dram_ctrl.hh
This patch adds a configuration that simplifies evaluation of DRAM
controller configurations by automating a sweep of stride size and
bank parallelism. It works in a rather unconventional way, as it needs
to print the traffic generator stimuli based on the memory
organisation. Hence, it starts by configuring the memory, then it
prints a traffic-generator config file, and loads it.
The resulting stats have one period per data point, identified by the
stride size, and the number of banks being used.
