ARM Devices

Void Linux provides packages and images for several ARM devices. Installing Void on such devices can be done in several ways:

Pre-built images: images that can be flashed directly onto an SD card or other storage medium, but which give you a limited partition layout, and require manual expansion if you wish to increase the size of the partitions;
Tarball installation: PLATFORMFS and ROOTFS tarballs that can be extracted to a previously prepared partition scheme; and
Chroot installation: follows most of the steps outlined in the chroot guide.

This guide also outlines configuration steps that are mostly specific to such devices.

Since most of the commands in this guide will be run on external storage, it is important to run sync(1) before removing the device.

Installation

If you are installing Void Linux on one of the ARM devices covered in the "Supported platforms" page, make sure to read its section thoroughly.

Pre-built images

After downloading and verifying an image, it can be written to the relevant media with cat(1), pv(1), or dd(1). For example, to flash it onto an SD card located at /dev/mmcblk0:

# dd if=<image>.img of=/dev/mmcblk0 bs=4M status=progress

Custom partition layout

Customizing an installation - for example, with a custom partition layout - requires a more involved process. Two available options are:

Tarball installation; and - Chroot installation.

To prepare the storage for these installation methods, it is necessary to partition the storage medium and then mount the partitions at the correct mount points.

The usual partitioning scheme for ARM devices requires at least two partitions, on a drive formatted with an MS-DOS partition table:

one formatted as FAT32 with partition type 0c, which will be mounted on /boot;
one that can be formatted as any file system that Linux can boot from, such as ext4, which will be mounted on /. If you're using an SD card, you can create the ext4 file system with the ^has_journal option - this disables journaling, which might increase the drive's life, at the cost of a higher chance of data loss.

There are a variety of tools available for partitioning, e.g. cfdisk(8).

To access the newly created file systems, it is necessary to mount them. This guide will assume that the second partition will be mounted on /mnt, but you may mount it elsewhere. To mount these filesystems, you can use the commands below, replacing the device names with the appropriate ones for your setup:

/mnt/boot ```

#### Tarball installation

First, [download and verify](../../index.md#downloading-installation-media)
a PLATFORMFS or ROOTFS tarball for your desired platform and [prepare your
storage medium](#custom-partition-layout). Then, unpack the tarball onto the
file system using [tar(1)](https://man.voidlinux.org/tar.1):

``` # tar xvfp <image>.tar.xz -C /mnt ```

#### Chroot installation

It is also possible to perform a chroot installation, which can require the
`qemu-user-static` package together with either the `binfmt-support` or
`proot` package if a computer with an incompatible architecture (such as
i686) is being used. This guide explains how to use the
`qemu-<platform>-static` program from `qemu-user-static` with
[proot(1)](https://man.voidlinux.org/proot.1).

First, [prepare your storage medium](#custom-partition-layout). Then, follow
either the [XBPS chroot installation](../chroot.md#the-xbps-method) or the
[ROOTFS chroot installation](../chroot.md#the-rootfs-method) steps, using
the appropriate architecture and base packages, some of which are listed in
the "[Supported Platforms](./platforms.md)" section.

Finally, follow the [chroot configuration steps](../chroot.md#configuration)
steps, but instead of using the
[chroot(1)](https://man.voidlinux.org/chroot.1)  command to [enter the
chroot](../chroot.md#entering-the-chroot), use the following command,
replacing `<platform>` with `arm` for armv6l and armv7l devices, and with
`aarch64` for aarch64 devices:

``` # proot -q qemu-<platform>-static -r /mnt -w / ```

## Configuration

Some additional configuration steps need to be followed to guarantee a
working system. Configuring a [graphical
session](../../../config/graphical-session/index.md) should work as normal.

### Logging in

For the pre-built images and tarball installations, the `root` user password
is `voidlinux`.

### fstab

The `/boot` partition should be added to `/etc/fstab`, with an entry similar
to the one below. It is possible to boot without that entry, but updating
the kernel package in that situation can lead to breakage, such as being
unable to find kernel modules, which are essential for functionality such as
wireless connectivity. If you aren't using an SD card, replace
`/dev/mmcblk0p1` with the appropriate device path.

``` /dev/mmcblk0p1 /boot vfat defaults 0 0 ```

### System time

Several of the ARM devices supported by Void Linux don't have battery
powered real time clocks (RTCs), which means they won't keep track of time
once powered off. This issue can present itself as HTTPS errors when
browsing the Web or using the package manager. It is possible to set the
time manually using the [date(1)](https://man.voidlinux.org/date.1)
utility. In order to fix this issue for subsequent boots, install and enable
[an NTP client](../../../config/date-time.md#ntp). Furthermore, it is
possible to install the `fake-hwclock` package, which provides the
`fake-hwclock` service.
[fake-hwclock(8)](https://man.voidlinux.org/fake-hwclock.8) periodically
stores the current time in a configuration file and restores it at boot,
leading to a better initial approximation of the current time, even without
a network connection.

**Warning**: Images from before 2020-03-16 might have an issue where the
installation of the `chrony` package, the default NTP daemon, is incomplete, and
the system will be missing the `chrony` user. This can be checked in the output
of the [getent(1)](https://man.voidlinux.org/getent.1) command, which will be
empty if it doesn't exist:

``` $ getent group chrony chrony:x:997 ```

In order to fix this, it is necessary to reconfigure the `chrony` package
using [xbps-reconfigure(1)](https://man.voidlinux.org/xbps-reconfigure).

### Graphical session

The `xf86-video-fbturbo` package ships a modified version of the [DDX Xorg
driver](../../../config/graphical-session/xorg.md#ddx) found in the
`xf86-video-fbdev` package, which is optimized for ARM devices. This can be
used for devices which lack more specific drivers.