This repository is part of a deprecated version of HERO. Please refer to the current HERO repository for the current accelerator hardware.
HERO is our open-source, FPGA-based, heterogeneous embedded SoC research platform that combines a fully-modifiable RISC-V manycore accelerator with an ARM Cortex-A host processor.
HERO consists of many different hard- and software components. This repository contains the bigPULP hardware platform, i.e., the sources and build scripts to generate the FPGA bitstream implementing the RISC-V manycore accelerator of HERO.
Being the big brother of the open-source, multicore, Parallel Ultra-Low Power (PULP) computing platform jointly developed by ETH Zurich and the University of Bologna, bigPULP is based on the same cluster architecture and sources. Depending on the target FPGA, bigPULP uses one or multiple PULP clusters that share an L2 instruction and data memory, a global interconnect, synchronization infrastructure, as well as the Remap Address Block (RAB) - a software-managed I/O memory management unit - which allows accelerator to coherently access the platform's main memory including support for shared virtual memory (SVM).
For further information about HERO, refer to our HERO paper at https://arxiv.org/abs/1712.06497 and the HERO website https://www.pulp-platform.org/hero/.
Detailed HOWTOs on how to build and use the HERO platform can be found here:
https://pulp-platform.org/hero/doc/
For more information about the PULP project in general, please refer to the official PULP platform website:
https://www.pulp-platform.org/
Before being able to build a bitstream or simulate the FPGA design, get the latest version of the IP cores used inside bigPULP:
./update-ips
This will download all the required IPs, solve dependencies and generate the
scripts by calling ./generate-scripts
.
Then, enter the fpga
directory and adjust the sourceme.sh
script. Select
the target board and adjust the path to the Vivado-specific simulation libraries.
Source the sourceme.sh
script:
. sourceme.sh
Generate all the Xilinx IP cores used inside bigPULP:
make ips
After having downloaded the PULP IP cores, having set up and sourced the
sourceme.sh
script and having generated the Xilinx IP cores as shown in the
preparation section, you can start generating an FPGA bitstream. To this end,
enter the fpga
directory and execute
make synth-pulp_cluster
to start Xilinx Vivado and synthesize the cluster netlist. Afterwards, run
make synth-pulp_soc
to start Xilinx Vivado and synthesize the SoC containing possibly multiple clusters as well as SoC-level IP cores.
Finally, the top-level design containing the bigPULP SoC and the interfaces
to the host can be generated and an FPGA bitstream can be generated. To this
end, enter the folder bigpulp-z-70xx
and run
make clean gui
to start Xilinx Vivado, synthesize the top-level netlist and generate the FPGA bitstream.
NOTE: When targeting other platforms such as the Xilinx Zynq UltraScale+ MPSoC
or the Juno ARM Development Platform, enter the corresponding directory, i.e.,
bigpulp-zux
or bigpulp
, respectively.
How to create a bootable HERO system image using the generated FPGA bitstream is is shown in a detailed HOWTO at: https://pulp-platform.org/hero/doc/software
To debug the bigPULP platform, this repository provides a set of simulation scripts and testbenches.
NOTE: The simulation platform only models the bigPULP subsystem. The host is not part of the simulation. Instead, the host is modeled using an AXI master plug driven by the testbench, and the shared main memory is modeled using Xilinx BRAM IP cores.
After having downloaded the PULP IP cores, having set up the sourceme.sh
script
and having generated the Xilinx IP cores as shown in the preparation section, you
need to download the free AMBA4 AXI-Lite Verification IP from SysWip:
http://syswip.com/axi4-lite-verification-ip
and extract the archive.
Then, open the sourceme.sh
script and adjust the AXI4LITE_VIP_PATH
variable
to point to where you just extracted the archive.
Source the sourceme.sh
script:
. sourceme.sh
Next, copy the .slm
files, i.e., memory initialization files for the application
of interest, to the folder sim-bigpulp-z-70xx/tb/current/slm_files
. These files
are generated by the PULP SDK when compiling an application. They are typically found
inside the build directory build/system-bigpulp*/
.
Finally, enter the folder sim-bigpulp-z-70xx/vivado
and run
make clean gui
to start Xilinx Vivado, compile the entire design and start the RTL simulation.
NOTE: When targeting other platforms such as the Xilinx Zynq UltraScale+ MPSoC
or the Juno ARM Development Platform, enter the corresponding directory, i.e.,
sim-bigpulp-zux/vivado
or sim-bigpulp/vivado
, respectively.
After being fully setup as explained in the Getting Started section, this root repository is structured as follows:
-
fe
contains the front-end RTL code of bigPULP. -
fe/rtl
contains the main platform RTL code including packages a include files. -
fe/ips
contains all IPs downloaded byupdate-ips
script. -
fpga
contains all FPGA-specific files to build and simulate the RTL code including:fpga/rtl
: FPGA-specific RTL code.fpga/ips
: Vivado build scripts to generate the Xilinx IP cores instantiated in the design.fpga/pulp_cluster
: Vivado build scripts to generate the netlist of the PULP cluster IP instantiated in the design.fpga/pulp_soc
: Vivado build scripts to generate the netlist of the bigPULP SoC containing one or multiple PULP clusters as well as SoC-level IPs such as the RAB.fpga/bigpulp-z-70xx
: Vivado build scripts and top-level RTL files to generate the bigPULP bitstream and Xilinx SDK files for HERO based on Xilinx Zynq-7000 SoCs.fpga/sim-bigpulp-z-70xx
: Vivado scripts and testbenches to simulate bigPULP when targeting Xilinx Zynq-7000 SoCs.fpga/bigpulp-zux
: Vivado build scripts and top-level RTL files to generate the bigPULP bitstream, Xilinx SDK and PetaLinux input files for HERO based on Xilinx Zynq UltraScale+ MPSoCs.fpga/sim-bigpulp-zux
: Vivado scripts and testbenches to simulate bigPULP when targeting Xilinx Zynq UltraScale+ MPSoCs.fpga/bigpulp
: Vivado build scripts and support files to generate the multicluster bigPULP bitstream for HERO based on the ARM Juno Development Platform.fpga/sim-bigpulp
: Vivado scripts and testbenches to simulate bigPULP when targeting the ARM Juno Development Platform.
-
ipstools
contains the utilities to download and manage the IPs and their dependencies. -
ips_list.yml
contains the list of IPs required directly by the platform. Notice that each of them could in turn depend on other IPs, so you will typically find many more IPs in theips
directory than are listed in this file. -
rtl_list.yml
contains the list of places where local RTL sources are found (e.g.fe/rtl/components
).
The RTL platform has the following requirements:
- Relatively recent Linux-based operating system; we tested Ubuntu 16.04 and CentOS 7.
- Xilinx Vivado Design Suite version 2017.2.
- ModelSim in reasonably recent version (we tested it with version 10.6b).
- Python 3.4, with the
pyyaml
module installed (you can get that withpip3 install pyyaml
).
The PULP platforms are highly hierarchical and the Git repositories for the various
IPs follow the hierarchy structure to keep maximum flexibility.
Most of the complexity of the IP updating system are hidden behind the
update-ips
and generate-scripts
Python scripts; however, a few details are
important to know:
- Do not assume that the
master
branch of an arbitrary IP is stable; many internal IPs could include unstable changes at a certain point of their history. Conversely, in top-level platforms (pulpissimo
,pulp
,bigPULP
) we always use stable versions of the IPs. Therefore, you should be able to use themaster
branch ofbigPULP
safely. - By default, the IPs will be collected from GitHub using HTTPS. This makes it
possible for everyone to clone them without first uploading an SSH key to
GitHub. However, for development it is often easier to use SSH instead,
particularly if you want to push changes back.
To enable this, just replace
https://github.com
with[email protected]
in theipstools_cfg.py
configuration file in the root of this repository.
The tools used to collect IPs and create scripts for simulation have many features that are not necessarily intended for the end user, but can be useful for developers; if you want more information, e.g. to integrate your own repository into the flow, you can find documentation at https://github.com/pulp-platform/IPApproX/blob/master/README.md
The supported way to provide external contributions is by forking one of our
repositories, applying your patch and submitting a pull request where you
describe your changes in detail, along with motivations.
The pull request will be evaluated and checked with our regression test suite
for possible integration.
If you want to replace our version of an IP with your GitHub fork, just add
group: YOUR_GITHUB_NAMESPACE
to its entry in ips_list.yml
or
ips/pulp_soc/ips_list.yml
.
While we are quite relaxed in terms of coding style, please try to follow these
recommendations:
https://github.com/pulp-platform/ariane/blob/master/CONTRIBUTING.md
Currently, the bigPULP platform cannot be built for the Juno ARM Development
Platform from the sources in this repository since part of the required IP cores
and top-level wrappers from ARM are not freely available. For internal development,
download the juno-support
repository from the internal GitLab server and
configure JUNO_SUPPORT_PATH
in sourceme.sh
accordingly.
For support on any issue related to this platform or any of the IPs, please add an issue to our tracker on https://github.com/pulp-platform/bigPULP/issues