Funtoo Linux Installation on RPI

Introduction

This is an extension and amplification of Funtoo_Linux_Installation_on_ARM. It attempts to systematize and automate as much as possible of steps required to get Funtoo running on the 32 bit ARM Raspberry Pi device.

This is an update of Crossdev_Automation, reflecting the changes needed to accomodate the new kits structure of Funtoo, and to clean up the scripting used for automation. The document will remain available for reference purposes.

Installation Overview

1. #Create Your Installation Settings
2. #Install the Stage 3 Tarball
3. #Install the Firmware
4. #Configure Your System
5. #Install Binary Kernel, Modules and dtbs
6. #Cross-compile Kernel, Modules and dtbs from Source
7. #Use QEMU To chroot
8. #Partition and Format an SDCard
9. #Deploy Installation to SDCard
10. #Transfer the SDCard to the Raspberry Pi and Boot
11. #Enjoy!

Get the Bash Script (Or Not)

If You Want to Try the Script

Development code to automate completely the process of installing is available on github. The structure of the file sysroot.sh should roughly correspond to the information contained here in this document. The script contains enough functionality to:

• get the latest stage3 tarball and verify its integrity
• install necessary open and closed source firmware
• configure the system:
  • modify fstab to make a simple partition structure (no swap)
  • set a root password interactively
  • add appropriate services to default run level
  • set up the software clock
  • link to accelerated video libraries
  • set boot parameters
• install a kernel
  • rpi binary kernel, dtbs, and modules
  • OR cross compile a kernel, modules and dtbs from source
• install QEMU and use binary translation to allow the use of chroot for further tweaking
• partition and format an sdcard
• copy the bootable configured stage3 to the sdcard

The script is designed to used on a machine that mounts the sdcard that will be used on the pi.

Too use the basic install functionality of the script, edit the config file (pay attention to the SDCARD_DEV variable) and then

root # source sysroot.sh && sysroot_install

Read the questions carefully and answer yes or no.

If You Want to Do it Yourself

Read the document here and follow the steps, referring sysroot.sh to reassure yourself of the correctness of the installer script.

Create Your Installation Settings

Confguration your installation. These variables are referencecd by the sysroot.sh script and by this document.

   config (bash source code) - Set your install configuration variables

KERNEL_WORK=/mnt/shared/rpi_kernel
RPI_KERN_BRANCH=rpi-4.14.y

SYSROOT_WORK=/mnt/shared/sysroots
STAGE3_URL=https://build.funtoo.org/1.3-release-std/arm-32bit/raspi3/2019-01-25/stage3-raspi3-1.3-release-std-2019-01-25.tar.xz
CHOST=armv7a-hardfloat-linux-gnueabi
CFLAGS="-O2 -pipe -march=armv7-a -mtune=cortex-a53 -mfpu=neon-vfpv4 -mfloat-abi=hard"

#SDCARD_DEV=mmcblk0p
SDCARD_DEV=sdb

INSTALL_VARS=(KERNEL_WORK RPI_KERN_BRANCH SYSROOT_WORK STAGE3_URL CHOST CFLAGS SDCARD_DEV)

Install the Stage 3 Tarball

Download the current Funtoo stage 3 build appropriate for your Raspberry Pi device. Check the Raspberry_Pi_(Version_3) page, to see the version available for versions 3 of the Pi. Here we download the version for version 3 by setting the STAGE_URL variable in our configuration file.

We need to save the archive to $STAGE3_ARCHIVE and unpack it to $SYSROOT. Back up or remove any previous work in that local.

root # export SYSROOT=$SYSROOT_WORK/$CHOST
root # export STAGE3_ARCHIVE=/tmp/stage3-latest.tar.xz
root # mv -n $SYSROOT $SYSROOT.old
root # mkdir -p $SYSROOT
root # wget ${STAGE_URL} -O ${STAGE3_ARCHIVE}
root # tar xpfv ${STAGE3_ARCHIVE} -C ${SYSROOT}

Install the Firmware

Make your work directory and clone the official firmware repo into it. Copy the appropriate boot firmware files to the sysroot, along with the video acceleration binaries. If you want to use the wireless networking function, you need the bcrm firmware as well.

root # mkdir -p ${KERNEL_WORK}
root # git clone --depth 1 git://github.com/raspberrypi/firmware/ ${KERNEL_WORK}/firmware
root # cp ${KERNEL_WORK}/firmware/boot/{bootcode.bin,fixup*.dat,start*.elf} ${SYSROOT}/boot
root # cp -r ${KERNEL_WORK}/firmware/hardfp/opt ${SYSROOT}
root # git clone --depth 1 https://github.com/RPi-Distro/firmware-nonfree ${KERNEL_WORK}/firmware-nonfree
root # git --git-dir=${KERNEL_WORK}/firmware-nonfree/.git --work-tree=${KERNEL_WORK}/firmware-nonfree pull origin
root # mkdir -p ${SYSROOT}/lib/firmware
root # cp -r ${KERNEL_WORK}/firmware-nonfree/brcm ${SYSROOT}/lib/firmware

Configure Your System

Here, we attempt to encapsulate the instructions from Funtoo_Linux_Installation_on_ARM. There are two ways to do this. Here we alter files and symlinks in $SYSROOT/etc directly.

We could also chroot into $SYSROOT using QEMU as described below to install packages, edit files and use rc-update directly to set up services.

Set Up Mount Points

Alter $SYSROOT/etc/fstab as follows. We remove the swap, and alter the storage device name and partition file types. We also remove the /dev/cdrom device.

   Warning

No swap is configured. If you need to control out of memory conditions (e.g. when compiling chromium) you need to configure a swap parition or use No results. A partition must also be created and formatted on the device (probably on the sd card, but usb block memory devices can be used if necessary).

   $SYSROOT/etc/fstab

/dev/mmcblk0p1  /boot   vfat    noauto,noatime  1 2
/dev/mmcblk0p2  /       ext4    noatime         0 1

We can use the following No results code.

root # sed -i "s/\/dev\/sda1.*/\/dev\/mmcblk0p1 \/boot vfat defaults 0 2/" ${SYSROOT}/etc/fstab
root # sed -i "s/\/dev\/sda2.*//" ${SYSROOT}/etc/fstab
root # sed -i "s/\/dev\/sda3.*/\/dev\/mmcblk0p2 \/ ext4  defaults 0 1/" ${SYSROOT}/etc/fstab
root # sed -i "s/\#\/dev\/cdrom.*//" ${SYSROOT}/etc/fstab

Set Up Root Password

Here we interactively add a root password to log in with to $SYSROOT/etc/shadow.

root # sed -i "s|root\:\*|root\:`(openssl passwd -1)`|" $SYSROOT/etc/shadow

Set Up Networking

We add dhcpcd as a default runlevel service.

root # ln -sf /etc/init.d/dhcpcd ${SYSROOT}/etc/runlevels/default

Set Up SSH Access

If you want to ssh to the board as root, you need to allow it explicitly and we add sshd as a default runlevel service.

root # echo "PermitRootLogin yes" >> ${SYSROOT}/etc/ssh/sshd_config
root # ln -sf /etc/init.d/sshd ${SYSROOT}/etc/runlevels/default

Set Up the Software Clock

Let's set up the software clock. This is Raspberry Pi specific, and due to its lack of a stock RTC chipset. This has ramifications for maintaining the correct time via a pacakge like No results.

root # ln -sf /etc/init.d/swclock ${SYSROOT}/etc/runlevels/boot
root # rm ${SYSROOT}/etc/runlevels/boot/hwclock
root # mkdir -p ${SYSROOT}/lib/rc/cache
root # touch ${SYSROOT}/lib/rc/cache/shutdowntime

Disable Serial Console Access

Let's prevent serial consoles from spawning. If you have a need for this, you'll be able to set it up yourself.

root # sed -i "s/s0\:.*/\#&/" ${SYSROOT}/etc/inittab

Link to Accelerated Video Libraries

You must add /opt/vc/lib to $LD_LIBRARY_PATH in the shell, or use the env-update functionality of Funtoo if you want to link against these firmware libraries. This is critical if you want to do any accelerated graphics or gpu level work. Here we add an entry to the appropriate configuration file which env-update will pick up whenever we source /etc/profile.

root # echo "LDPATH=\"/opt/vc/lib\"" > ${SYSROOT}/etc/env.d/99vc

If you want to try building native vc4 acceleration with media-libs/mesa you must unmask the appropriate USE flags at the profile level and VIDEO_CARDS="vc4" in make.conf.

root # cat > /etc/portage/profile/portage.use.mask << EOF
root ##i##media-libs/mesa -video_cards_vc4 
root ##i##x11-libs/libdrm -video_cards_vc4
root ##i##EOF

If /var/log/Xorg.0.log is flooded with messages of the following type:

(EE) modeset(0): Failed to get GBM bo for flip to new front.
(EE) modeset(0): present flip failed

the workaround is to disable the PageFlip parameter for the modesetting driver.

To do this, as a root user create a file 20-displaylink.conf under /usr/share/X11/xorg.conf.d/ with the following content:

   $SYSROOT/usr/share/X11/xorg.conf.d/20-displaylink.conf

Section "Device"
  Identifier "DisplayLink"
  Driver "modesetting"
  Option "PageFlip" "false"
EndSection

Configure the Boot Parameters

root # cat > ${SYSROOT}/boot/cmdline.txt << EOF
root ##i## dwc_otg.lpm_enable=0 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
root ##i## EOF

Install Binary Kernel, Modules and dtbs

root # mkdir -p ${SYSROOT}/boot/overlays
root # cp ${KERNEL_WORK}/firmware/boot/dts/*.dtb ${SYSROOT}/boot/
root # cp ${KERNEL_WORK}/firmware/boot/dts/overlays/*.dtb* ${SYSROOT}/boot/overlays/
root # cp ${KERNEL_WORK}/firmware/boot/dts/overlays/README ${SYSROOT}/boot/overlays/
root # cp ${KERNEL_WORK}/firmware/boot/kernel7.img  ${SYSROOT}/boot/

Cross-compile Kernel, Modules and dtbs from Source

Install Crossdev

No results is a wonderful script for managing cross-compiling environments on Gentoo, but it is incompatible with Funtoo's improved gcc ebuilds. There is incomplete documentation of a pure Funtoo solution, but there has been no follow up on a complete implementation.

A simple solution is to create a local overlay named "crossdev", store gentoo ebuilds and patches in it, and use a crossdev command line switch to direct it to search the overlay for the appropriate ebuilds. This has the advantage of isolating all gentoo files and resulting binaries in a single directory.~

   Note

Please ensure that /etc/portage{package.keywords,package.mask,package.use} are all directories.

Make a Local Overlay

Let's follow the directions from Local_Overlay, and remove the .git subdirectory.~

root # mkdir /var/git/overlay
root # cd /var/git/overlay
root # git clone  https://github.com/funtoo/skeleton-overlay.git crossdev
root # rm -rf /var/git/overlay/crossdev/.git
root # echo "crossdev" > /var/git/overlay/crossdev/profiles/repo_name

Edit config files to match.

   /etc/portage/repos.conf/crossdev.conf - Add the crossdev overlay to portage

[crossdev]
location = /var/git/overlay/crossdev
auto-sync = no
priority = 10

Sparse Checkout Gentoo GCC Ebuilds

Let's make a sparse checkout of the main Gentoo repo.

root # cd /var/git/overlay/crossdev
root # git init
root # git remote add origin git://github.com/gentoo/gentoo.git
root # git config core.sparseCheckout true
root # echo "sys-devel/gcc" >> .git/info/sparse-checkout
root # git pull --depth=1 origin master

Unmask and Emerge Crossdev

root # echo "sys-devel/crossdev **" >> /etc/portage/package.keywords/crossdev
root # echo "=sys-devel/crossdev-99999999" >> /etc/portage/package.unmask/crossdev
root # emerge crossdev

Install Cross Compilation Tool Chain

root # crossdev -S --ov-gcc /var/git/overlay/crossdev -t ${CHOST}

Retrive Raspberry Pi Kernel Sources

root # git clone https://github.com/raspberrypi/linux.git ${KERNEL_WORK}/linux

Clean and Update Kernel Sources

root # git --git-dir=${KERNEL_WORK}/linux/.git --work-tree=${KERNEL_WORK}/linux clean -fdx
root # git --git-dir=${KERNEL_WORK}/linux/.git --work-tree=${KERNEL_WORK}/linux checkout master
root # git --git-dir=${KERNEL_WORK}/linux/.git --work-tree=${KERNEL_WORK}/linux fetch --all
root # git --git-dir=${KERNEL_WORK}/linux/.git --work-tree=${KERNEL_WORK}/linux branch -D ${RPI_KERN_BRANCH}
root # git --git-dir=${KERNEL_WORK}/linux/.git --work-tree=${KERNEL_WORK}/linux checkout ${RPI_KERN_BRANCH}

Make the Default Config

The next set of make commands take place in the kernel source directory.

root # cd ${KERNEL_WORK}/linux

There are many useful make targets to control kernel configs. In particular, the architecture specific ones are most useful in cross-compiling applications. You can see all available architecture specfic default configurations with the following command.

root # make -j$(nproc) \
root ##i## ARCH=arm \
root ##i## CROSS_COMPILE=${CHOST}- \
root ##i## make_defconfig_help 
root # Architecture specific targets (arm):
... <targets we don't need> ...

acs5k_defconfig          - Build for acs5k
acs5k_tiny_defconfig     - Build for acs5k_tiny
am200epdkit_defconfig    - Build for am200epdkit
assabet_defconfig        - Build for assabet
at91_dt_defconfig        - Build for at91_dt
axm55xx_defconfig        - Build for axm55xx
badge4_defconfig         - Build for badge4
root ##r##bcm2709_defconfig        - Build for bcm2709
bcm2835_defconfig        - Build for bcm2835
bcm_defconfig            - Build for bcm
bcmrpi_defconfig         - Build for bcmrpi
cerfcube_defconfig       - Build for cerfcube
clps711x_defconfig       - Build for clps711x
...<lots o configs>...
zeus_defconfig           - Build for zeus
zx_defconfig             - Build for zx

...<more targets we don't need> ...

root # make -j$(nproc) \
root ##i## ARCH=arm \
root ##i## CROSS_COMPILE=${CHOST}- \
root ##i## bcm2709_defconfig

Configure the Kernel

root # make -j$(nproc) \
root ##i## ARCH=arm \
root ##i## CROSS_COMPILE=${CHOST}- \
root ##i## MENUCONFIG_COLOR=mono \
root ##i## menuconfig

Build and Install the Kernel

root # make -j$(nproc) \
root ##i## ARCH=arm \
root ##i## CROSS_COMPILE=${CHOST}- \
root ##i## zImage dtbs modules

root # make -j$(nproc) \
root ##i## ARCH=arm \
root ##i## CROSS_COMPILE=${CHOST}- \
root ##i## INSTALL_MOD_PATH=${SYSROOT} \
root ##i## modules_install

root # mkdir -p ${SYSROOT}/boot/overlays
root ##i## cp arch/arm/boot/dts/*.dtb ${SYSROOT}/boot/
root ##i## cp arch/arm/boot/dts/overlays/*.dtb* ${SYSROOT}/boot/overlays/
root ##i## cp arch/arm/boot/dts/overlays/README ${SYSROOT}/boot/overlays/

root # scripts/mkknlimg arch/arm/boot/zImage ${SYSROOT}/boot/kernel7.img

Remove Kernel Headers and Source Links

root # rm ${SYSROOT}/lib/modules/`get_kernel_release`/{build,source}

Backup Kernel Config

root # mkdir -p ${SYSROOT}/etc/kernels
root # cp -i ${KERNEL_WORK}/linux/.config ${SYSROOT}/etc/kernels

Use QEMU To chroot

No results relies upon KVM and the associated kernel module, called either kvm_intel or kvm_amd, depending on the architecture the kernel is running on. Please see KVM to find out how to get these kernel modules loaded and virtualization working.

Install a QEMU Chroot

root # echo "app-emulation/qemu static-user" > /etc/portage/package.use/qemu
root # echo "dev-libs/libpcre static-libs" >> /etc/portage/package.use/qemu
root # echo "sys-apps/attr static-libs" >> /etc/portage/package.use/qemu
root # echo "dev-libs/glib static-libs" >> /etc/portage/package.use/qemu
root # echo "sys-libs/zlib static-libs" >> /etc/portage/package.use/qemu
root # echo "QEMU_SOFTMMU_TARGETS=\"arm\"" >> /etc/portage/make.conf
root # echo "QEMU_SOFTMMU_TARGETS=\"\${QEMU_SOFTMMU_TARGETS} arm\"" >> /etc/portage/make.conf
root # echo 'QEMU_USER_TARGETS="arm"' >> /etc/portage/make.conf
root # echo 'QEMU_USER_TARGETS="${QEMU_USER_TARGETS} arm"' >> /etc/portage/make.conf
root # emerge -q app-emulation/qemu
root # quickpkg app-emulation/qemu
root # ROOT=${SYSROOT}/ emerge -q --usepkgonly --oneshot --nodeps qemu

Example: Chroot with ARM Emulation

root # source sysroot.sh && sysroot_chroot $SYSROOT_WORK/$CHOST
root # export PS1="(chroot) $PS1"
(chroot) # ego profile
=== Enabled Profiles: ===

        arch: arm-32bit
       build: current
     subarch: raspi3
      flavor: core
     mix-ins: (not set)


  NOTE: Meta-repo has not yet been cloned, so no kit information is available. Type ego sync to perform an initial
  clone of meta-repo.
(chroot) # ego sync
(chroot) # exit

Example: Run a Shell Script in the ARM Chroot

root # cat > /tmp/shell_test.sh << EOF
root ##i## #!/bin/sh
root ##i## ego profile
root ##i## EOF
root # . sysroot.sh && sysroot_run_in_chroot $SYSROOT_WORK/$CHOST /tmp/shell_test.sh
=== Enabled Profiles: ===

        arch: arm-32bit
       build: current
     subarch: raspi3
      flavor: core
     mix-ins: (not set)


=== Python kit: ===

      branch: 3.4-prime

=== All inherited flavor from core flavor: ===

                         minimal (from core flavor)

Partition and Format an SDCard

root # export SDCARD=/dev/SDCARD_DEV

Randomize SDCard

root # dd if=/dev/urandom of=${SDCARD} bs=1M status=progress

Write Parition Scheme to SDCard

root # umount -Rl ${SDCARD}
root # sfdisk --no-reread --wipe always ${SDCARD} << EOF
root ##i## label: dos
root ##i## unit: sectors
root ##i## ${SDCARD}1 : start=        2048, size=     1048576, type=c
root ##i## ${SDCARD}2 : start=     1050624, type=83
root ##i## EOF

Format SDCard

Make sure you have No results installed.

root # mkfs.ext4 ${SDCARD}2
root # mkfs.vfat ${SDCARD}1

Deploy Installation to SDCard

root # mkdir -p /mnt/rpi
root # mount ${SDCARD}2 /mnt/rpi
root # mkdir -p /mnt/rpi/boot
root # mount ${SDCARD}1 /mnt/rpi/boot
root # rsync --archive \
root ##i##      --verbose \
root ##i##      --progress \
root ##i##      --exclude "var/git/*" \
root ##i##    ${SYSROOT}/{boot,bin,etc,home,lib,mnt,opt,root,run,sbin,srv,tmp,usr,var,dev,proc,sys} \
root ##i##    /mnt/rpi
root # umount /mnt/rpi/boot
root # umount /mnt/rpi