Google Fuchsia Embedded OS

Published on August 17, 2016

MAGENTA - HOW TO RUN YOUR OWN C SOURCE CODE BINARY

On August 15th, Google unveiled a new operative embedded system called Fuchsia based on Magenta kernel. Here below you will find a step by step guide to compile and run this new kernel under qemu. Moreover a manual tool-chain configuration in order to compile your own C-source example code.

The target architecture chosen is Arm64 CPU type arm926ej-s and the host is Ubuntu Linux 14.04 x86-64. The list of package in the following may not be fully exhaustive, especially if you install Ubuntu from scratch.

## Compiling and providing the buildtools

sudo apt-get install git libc-dev-bin gcc-multilib curl

mkdir -p fuchsia

pushd fuchsia

git clone https://fuchsia.googlesource.com/buildtools

git clone https://fuchsia.googlesource.com/magenta

pushd buildtools/

./update.sh

popd

## Compiling and providing the tool-chain for ARM target

## Available architectures: arm i386 aarch64 x86_64

sudo apt-get install texinfo libglib2.0-dev autoconf libsdl-dev \

build-essential bison flex

TARGET_ARCH="aarch64"

declare -i N_CPUS=$(nproc)

SYSROOT=$PWD/buildtools/sysroot

git clone https://fuchsia.googlesource.com/third_party/gcc_none_toolchains

ln -sf gcc_none_toolchains toolchain

pushd toolchain

./doit -a $TARGET_ARCH -f -j$N_CPUS

popd

TCBIN_PATH=$(readlink -f $PWD/toolchain/$TARGET_ARCH-*/bin)

export PATH=$PATH:$TCBIN_PATH

## Building Magenta for pc-x86-64 target

## Available build targets: magenta-pc-x86-64 magenta-qemu-arm32

## magenta-qemu-arm64 pc-x86-64-test pc-x86-test qemu-virt-a15-test

## qemu-virt-a53-test rpi3-test

pushd magenta

make -j$N_CPUS magenta-qemu-arm64

popd

## Compile qemu and make Magenta run with it

git clone https://fuchsia.googlesource.com/third_party/qemu

pushd qemu

git checkout fuchsia

./configure --target-list=$TARGET_ARCH-softmmu \

--prefix=$PWD/../qemu-runtime

make -j$N_CPUS install

export PATH=$PWD/../qemu-runtime/bin:$PATH

popd

pushd magenta/build-magenta-qemu-arm64

declare -i REAL_MEM_KB QEMU_MEM_MB N_CPUS_QEMU

N_CPUS_QEMU=$[(N_CPUS+1)/2]

REAL_MEM_KB=$(grep -e ^MemTotal: /proc/meminfo | tr -cd [0-9])

QEMU_MEM_MB=$[($REAL_MEM_KB+1024)/2048]

test $QEMU_MEM_MB -gt 512 && QEMU_MEM_MB=512

qemu-system-$TARGET_ARCH -m $QEMU_MEM_MB -nographic \

-machine virt -cpu cortex-a53 -kernel magenta.elf -append ''

#> ls /boot/bin

#> core-tests

#> thread-depth-test

#> dlog

# to terminate qemu

CTRL-A X

popd

## Manual preparation of the current toolchain

export CC=aarch64-elf-gcc

export CXX=aarch64-elf-g++

export LD=aarch64-elf-ld.gold

export AR=aarch64-elf-ar

export AS=aarch64-elf-as

export NM=aarch64-elf-nm

export STRIP=aarch64-elf-strip

export RANLIB=aarch64-elf-ranlib

export DLLTOOL=aarch64-elf-dlltool

export OBJDUMP=aarch64-elf-objdump

export RESCOMP=aarch64-elf-windres

export WINDRES=aarch64-elf-windres

CFLAGS="-Wall -Wextra -ffunction-sections -fdata-sections -fPIC -mcpu=cortex-a53 -std=c11"

CFLAGS="$CFLAGS -include config-global.h -include config-user.h"

CFLAGS="$CFLAGS $(for i in $(find ../global ../system ../third_party -name include); do echo -n "-I $i "; done)"

export CFLAGS

export HOSTING_CRT0=./ulib/crt1.o

LIB_PATH_1=$(dirname $TCBIN_PATH)/lib/gcc/$TARGET_ARCH-elf/5.3.0

LDFLAGS="-s -nostdlib -Lkernel -Lsystem -Lthird_party -z max-page-size=4096 --gc-sections -z combreloc -z relro -z now -z text --hash-style=gnu --eh-frame-hdr --build-id -pie -dynamic-linker ld.so.1 $HOSTING_CRT0"

export LDFLAGS

EXTRA_LIBS="$(find ./ulib/ -name \*.so.abi) $LIB_PATH_1/libgcc.a"

## Compile and run your own code

cp -f ../third_party/uapp/kilo/kilo.c chilo.c

wget -c roberto.foglietta.name/pub/mk/armstrong.c

rm -f chilo.o chilo armstrong.o armstrong extra.bootfs

$CC $CFLAGS -c armstrong.c -o armstrong.o

$CC $CFLAGS -c chilo.c -o chilo.o -fPIC -Wno-unused-parameter

$LD $LDFLAGS armstrong.o $EXTRA_LIBS -o armstrong

$LD $LDFLAGS chilo.o $EXTRA_LIBS -o chilo

## Remake the extra.bootfs initrd image

file chilo armstrong

echo "bin/armstrong=./armstrong" > extra.manifest

echo "bin/chilo=./chilo" >> extra.manifest

../../buildtools/mkbootfs -o extra.bootfs extra.manifest

sync

## Run a new qemu instance of Magenta with the new initrd image

qemu-system-$TARGET_ARCH -m $QEMU_MEM_MB -nographic \

-machine virt -cpu cortex-a53 -kernel magenta.elf -initrd extra.bootfs -append ''

Index of all the articles

• Project Management, Decision Making, Technology Innovation, Leadership & Creativity, Economia, Cultura, Società e Costume, Progetti, Idee e di divulgazione.

Share alike

(C) 2016, Roberto A. Foglietta, licensed under Creative Common Attribution-NonCommercial-ShareAlike 4.0 International terms (CC BY-NC-SA 4.0).