README.linux

I experimented building the code in a 2018 Debian LTS release in a docker image. It almost works.

If I were to add a dockerfile for CI, it might look something like this:


# This is a bit of a lie. It installs the RISC tools as if we were building for a Linux
# RISC-V system, when we really prefer the riscv64-unknown-elf-blah form. This just gets 
# basic tools up.
dpkg --add-architecture riscv64
apt-get update               \
 && apt-get -y -q upgrade        \
 && apt-get -y -q install  \       
 git        \
 curl        \
 vim        \
 gcc        \
 gcc-riscv64-linux-gnu \
 g++-riscv64-linux-gnu


# This installs /opt/SEGGER/JLink/JLinkExe - What a gross name!
# /opt/SEGGER/JLink/*CL* may be more suited for headless/scripting use
# I ran into a dead end as the CL tools seem to work, but JLink wants
# to splash an X dialogue just to ask if we accept the license. Ugh.
# This whole section is optional if you dont have SEGGER pods in your life.
curl -daccept_license_agreement=accepted https://www.segger.com/downloads/jlink/JLink_Linux_x86_64.deb -O /tmp/blah.deb
dpkg -i JLink_Linux_x86_64.deb 
 apt-get -y -q install  \       
 libfreetype6 \
 libsm6 \
 libxrender-dev \
 libxrandr-dev \
 libxfixes3 \
 libxcursor1 \
 libfontconfig1 \

# Two manual tweaks are needed for now
Edit tools/common.mk. Change
PREFIX = riscv64-unknown-elf-
to
PREFIX = riscv64-linux-gnu-

Edit tools/kernel.mk
In GCC10, we use the -mno-relax flag. See
https://gcc.gnu.org/onlinedocs/gcc/RISC-V-Options.html
I need to test if we HAD to or just did. Since the
Linux versions are still GCC 7 (sigh) just remove the
unsupported -fno-release flag

#
# Fetch and build the code. 

git clone https://github.com/robertlipe/riscv7.git
cd riscv7/usr/sys/conf
make