esel-proc: the Emulating SErial Latchup PROCessor

Driven by intuition, a fair amount of brute force, and lack of time to research the problems and literature. ¯\_(ツ)_/¯

Latchup - Think you’re good at RTL? Prove it.

esel-proc is a generated SoC powered by the award-winning serv RISC-V processor. The processor executes fetches from a generated ROM that contains the cross-compiled C solution of the latchup problem. The processor communicates with the main latchup streaming interface via a databus peripheral rtl/eselproc_latchup_interface (LIF). In essence, esel-proc emulates the hardware by executing the C solution which samples and toggles the interface pins via Memory-mapped Input/Output (MMIO) to the LIF peripheral registers. (CODE for reference of my more traditional designs)

Note	Esel (orig. German, engl. "donkey"), because esel-proc is slow. Being fast is not a donkey’s optimization goal. Being reliable, easy to handle, and an all-around chill animals is, though.

usage

prerequisites

native debian

In utils/scripts/setup_helper.sh are tool build instructions for all requirements to run esel-proc on a debian-based distro.

The following installs all necessary tools inside the ESELPROC_ROOT

cd esel-proc
export ESELPROC_ROOT=${PWD}   # this repository's local copy
utils/scripts/setup_helper.sh # source setup helper
apt install $(get_apt_deps)   # install apt packages
setup venv .venv .            # install a python3 virtual env with dependencies

# prepare the environment variables and source .venv
. utils/scripts/env_helper.sh utils/scripts/.env .venv

# install a verilator
setup verilator "verilator-src" "verilator-build" "${VERILATOR_INSTALL_DIR}" "${VERILATOR_VERSION}"

# install a risc-v gnu toolchain
setup rvgnu "${RVGNU_INSTALL_DIR}"

docker

See docker/ for more details.

quick docker-compose

docker-compose -f docker/docker-compose.yml --env-file docker/.env up --build

run docker-compose

docker run -it -v"$PWD":/work-esel-proc JoGei/esel-proc-deps:latest-default-debian-stable
# in docker cd into mounted repo and source env vars and venv
cd /work-esel-proc
. utils/scripts/env_helper.sh docker/.env ../.venv

build

after dependencies resolved (docker or native), source the environment, then simply make

build a esel-proc solution for SOL

make [SOL=01_multiplier, 02_divider, ...]

This generates a ready to use latchup solution in build/rtl/Solution.v. Change SOL build variable to supported algorithms in problems/.

test

test a esel-proc solution for SOL

make test [SOL=01_multiplier,...]
# vcd treace in ESEL_ROOT/*.vcd

Warning

This is a "for fun" project, like solving the original latchup.app problems with traditional hardware design was for me. This project is far from "production grade" and heaviliy involved genAI to "glue" together the different tools, abstraction levels, and coding of the LIF variants.