Move firmware to common directory

.gitignore

@@ -3,3 +3,6 @@ precheck_results
 *.lst
 *.vcd
 *.gtkw
+*.vvp
+*.log
+build

Makefile

@@ -15,9 +15,10 @@
 # SPDX-License-Identifier: Apache-2.0
 MAKEFLAGS+=--warn-undefined-variables
 
-CARAVEL_ROOT?=$(PWD)/caravel
+CARAVEL_USER_PROJECT_ROOT:=$(shell readlink -f .)
+CARAVEL_ROOT?=${CARAVEL_USER_PROJECT_ROOT}/caravel
 PRECHECK_ROOT?=${HOME}/mpw_precheck
-MCW_ROOT?=$(PWD)/mgmt_core_wrapper
+MCW_ROOT?=${CARAVEL_USER_PROJECT_ROOT}/mgmt_core_wrapper
 SIM?=RTL
 
 export SKYWATER_COMMIT=c094b6e83a4f9298e47f696ec5a7fd53535ec5eb
@@ -59,6 +60,27 @@ install:
 simenv:
 	docker pull efabless/dv_setup:latest
 
+PATTERNS=$(shell cd verilog/dv && find * -maxdepth 0 -type d)
+DV_PATTERNS = $(foreach dv, $(PATTERNS), verify-$(dv))
+TARGET_PATH=$(shell pwd)
+VERIFY_COMMAND="cd ${TARGET_PATH}/verilog/dv/$* && \
+	export SIM=${SIM} && ${MAKE} sim"
+
+FIRMWARE_SOURCE_DIR := ${CARAVEL_USER_PROJECT_ROOT}/caravel_firmware
+FIRMWARE_BUILD_DIR := ${CARAVEL_USER_PROJECT_ROOT}/build
+FIRMWARE_GENERATOR ?= 'Unix Makefiles'
+
+.PHONY: configure-firmware
+configure_firmware:
+	cmake -DCMAKE_TOOLCHAIN_FILE=${FIRMWARE_SOURCE_DIR}/cmake/vexriscv_toolchain.cmake \
+	-B${FIRMWARE_BUILD_DIR} \
+	-G${FIRMWARE_GENERATOR} \
+	${FIRMWARE_SOURCE_DIR}
+
+.PHONY: firmware
+firmware: configure_firmware
+	cmake --build ${FIRMWARE_BUILD_DIR}
+
 .PHONY: setup
 setup: install check-env install_mcw pdk openlane
 
@@ -82,12 +104,12 @@ docker_run_verify=\
 		-e TARGET_PATH=${TARGET_PATH} -e PDK_ROOT=${PDK_ROOT} \
 		-e CARAVEL_ROOT=${CARAVEL_ROOT} \
 		-e TOOLS=/opt/riscv32i \
-		-e DESIGNS=$(TARGET_PATH) \
-		-e CORE_VERILOG_PATH=$(TARGET_PATH)/mgmt_core_wrapper/verilog \
+		-e DESIGNS=${TARGET_PATH} \
+		-e CORE_VERILOG_PATH=${TARGET_PATH}/mgmt_core_wrapper/verilog \
 		-e GCC_PREFIX=riscv32-unknown-elf \
-		-e MCW_ROOT=$(MCW_ROOT) \
-		-u $$(id -u $$USER):$$(id -g $$USER) efabless/dv_setup:latest \
-		sh -c $(verify_command)
+		-e MCW_ROOT=${MCW_ROOT} \
+		efabless/dv_setup:latest \
+		sh -c ${VERIFY_COMMAND}
 
 .PHONY: harden
 harden: $(blocks)
@@ -204,6 +226,3 @@ check-pdk:
 help:
 	cd $(CARAVEL_ROOT) && $(MAKE) help
 	@$(MAKE) -pRrq -f $(lastword $(MAKEFILE_LIST)) : 2>/dev/null | awk -v RS= -F: '/^# File/,/^# Finished Make data base/ {if ($$1 !~ "^[#.]") {print $$1}}' | sort | egrep -v -e '^[^[:alnum:]]' -e '^$@$$'
-
-
-

caravel_firmware/CMakeLists.txt

@@ -0,0 +1,7 @@
+cmake_minimum_required(VERSION 3.16)
+project(CaravelFirmware VERSION 0.1.0 LANGUAGES C CXX ASM)
+
+set(CMAKE_C_STANDARD 11)
+set(CMAKE_CXX_STANDARD 11)
+
+add_subdirectory(src)

caravel_firmware/README.md

@@ -0,0 +1,27 @@
+# Caravel firmware
+The files in this directory are a common place for firmware code to be written. Whilst a subdirectory now this directory should be made a separate repo and then "submoduled" in any caravel repo that requires it. This allows common aspects of the firmware to be developed independently of the design, but the design specifies exactly which version of firmware is relevant to the current state of the design.
+
+## Motivation
+The reason to move firmware builds into a single place is twofold:
+* All configuration necessary to compile the firmware is in one place. For users developing firmware it then becomes transparent what compiler flags, linker scripts etc... are required to compile their own firmware.
+* Firmware development continues independently of the design. Abstract classes and structs that are independent of the design can be developed separately to the design and the design specifies when it's ready to take those updates.
+
+## Building
+To build the firmware you need to install cmake (and optionally Ninja) and ensure that the GCC toolchain executables are added to the PATH. Cmake is a fantastic tool which is able to generate build scripts for multiple toolchains (GNU Make, Ninja, MSVC, Xcode) so that firmware can be built on any platform. For more information please consult [the cmake documentation](https://cmake.org/).
+
+### Configuration
+The build with cmake takes place in two parts; configuration, which generates the build files and building which does the compilation. To configure the cmake build run
+```bash
+cmake -DCMAKE_TOOLCHAIN_FILE=cmake/vexriscv_toolchain.cmake -Bbuild -GNinja
+```
+from this directory. This can be explained as:
+* `-DCMAKE_TOOLCHAIN_FILE=cmake/vexriscv_toolchain.cmake` tells cmake to load the toochain as specified by `vexriscv_toolchain.cmake`. This file just tells cmake where to find the compiler and some global additional compiler flags.
+* `-Bbuild` tells cmake to put the build files in a directory called `build`
+* `-GNinja` tells cmake which generator to use. This is optional and defaults to  whatever host you are building on, for Linux systems this is GNU Make. Ninja is a  fast and efficient alternative and I suggest using it.
+
+### Building
+Now that cmake has configured the build, the source code can be compiled. To do this simply run
+```bash
+cmake --build build/
+```
+which tells cmake to build all things in the `build/` directory. All the build artifacts are placed in the `build/` directory with the same layout as this directory.

caravel_firmware/cmake/vexriscv_toolchain.cmake

@@ -0,0 +1,18 @@
+# To use this file you must invoke cmake with -DCMAKE_TOOLCHAIN_FILE like so:
+# (From build directory)
+# `cmake -DCMAKE_TOOLCHAIN_FILE=cmake/riscv_toolchain.cmake .`
+
+find_path(RISCV_TOOLCHAIN_PATH "riscv32-unknown-elf-gcc" ENV PATH)
+message("RISC-V compiler found in: ${RISCV_TOOLCHAIN_PATH}")
+
+set(CMAKE_SYSTEM_NAME Generic)
+
+set(CMAKE_C_COMPILER ${RISCV_TOOLCHAIN_PATH}/riscv32-unknown-elf-gcc)
+set(CMAKE_CXX_COMPILER ${RISCV_TOOLCHAIN_PATH}/riscv32-unknown-elf-g++)
+
+set(RISCV_GENERAL_COMPILER_FLAGS "-g -nostdlib")
+set(RISCV_C_FLAGS ${RISCV_GENERAL_COMPILER_FLAGS})
+set(RISCV_CXX_FLAGS ${RISCV_GENERAL_COMPILER_FLAGS})
+
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${RISCV_C_FLAGS}")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${RISCV_CXX_FLAGS}")

caravel_firmware/environment/apt_requirements.txt

@@ -0,0 +1,30 @@
+# Requirements to install with apt
+
+# Shell tools
+bash-completion
+git
+vim
+
+# Firmware build dependencies
+ninja-build
+
+# RISC-V toolchain dependencies
+autoconf
+automake
+autotools-dev
+bc
+bison
+build-essential
+curl
+flex
+gawk
+gperf
+libexpat-dev
+libgmp-dev
+libmpc-dev
+libmpfr-dev
+libtool
+patchutils
+python3
+texinfo
+zlib1g-dev

caravel_firmware/environment/riscv_toolchain.dockerfile

@@ -0,0 +1,38 @@
+# SPDX-FileCopyrightText: 2020 Efabless Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# SPDX-License-Identifier: Apache-2.0
+
+ARG BASE_IMAGE=ubuntu:20.04
+FROM ${BASE_IMAGE}
+
+ENV TOOLCHAIN_DOWNLOAD_DIR=/tmp/riscv-gnu-toolchain
+ENV TOOLCHAIN_INSTALL_DIR=/opt/riscv32i
+
+ARG DEBIAN_FRONTEND=noninteractive
+
+COPY ./environment/apt_requirements.txt /tmp
+
+RUN apt-get update && \
+    apt-get install -y $(grep -v "^#" /tmp/apt_requirements.txt | tr "\n" " ")
+
+RUN git clone https://github.com/riscv/riscv-gnu-toolchain ${TOOLCHAIN_DOWNLOAD_DIR} && \
+    cd ${TOOLCHAIN_DOWNLOAD_DIR} && \
+    ./configure --prefix=${TOOLCHAIN_INSTALL_DIR} --with-arch=rv32i && \
+    make -j $(nproc) && \
+    cd / && \
+    rm -rf ${TOOLCHAIN_DOWNLOAD_DIR}
+
+ENV PATH=${TOOLCHAIN_INSTALL_DIR}/bin:${PATH}
+
+CMD /bin/bash