PULP Cluster

The pulp_cluster repository contains the structure of the cluster subsystem used in PULP chips. For more details on the internal architecture, see the README.md in the pulp repository.

The doc folder contains the draw.io schematic shown above, as well as the raw source to allow for updates, outlining the most important components in pulp_cluster, as well as the communication interfaces connecting these. While not a complete overview of all signals, this is meant as a slightly more detailed overview that can assist in development. Please be aware that the schematic may not be 100% accurate.

Dependencies

To build the cluster, you will need:

• Bender >= 0.24.0
• GNU Make >= 3.82
• Python >= 3.9
• RISCV GCC >= 11.2.0

We use Bender for hardware IP and dependency management; for more information on using Bender, please see its documentation. You can install Bender directly through the Rust package manager Cargo:

cargo install bender

Simulation

It is possible to run benchmarks on the cluster, either within PULP or as a separate IP. For simulation within PULP, you can directly go to the PULP repo and follow the README.

To simulate the cluster on its own, you can perform the following steps:

Warning: requires QuestaSim 2022.3 or newer.

1. Make sure the PULP RV32 toolchain is in your PATH. Please refer to PULP RISCV GCC toolchain to use a pre-built release. (At IIS, this is set up by the env script in step 4.)

2. Compile the hw:

   make checkout
   make scripts/compile.tcl
   make build
   

3. Download the sw stack and bare-metal tests:

   make pulp-runtime
   make regression_tests
   

4. Source the environment:

   source env/env.sh
   

5. Run the tests. Choose any test among the parallel_bare_tests and the mchan_tests, move into the related folder and do:

   make clean all run
   

   To use the GUI, add gui=1 to the previous command.