devsus/README

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Overview
========

Devsus is a script that builds bootable, libre Devuan (http://www.devuan.org/)
images for the Asus C201 Chromebook, one of the few laptops able to boot and run
without any non-free software, all the way down to the firmware level. The C201
is supported by Libreboot (http://www.libreboot.org/).

The images produced by Devsus contain a Linux-libre
(http://linux-libre.fsfla.org/) longterm kernel tuned for small size, good
performance and short boot times.

Some features of the RK3288 SoC, including built-in WiFi support, require use of
non-free software. Therefore, they are unsupported by Devsus. To compensate for
that, the Devsus kernel includes support for freedom-friendly devices:

	- Firmware for Atheros AR9271 based WiFi dongles
	- Drivers for Qualcomm CSR8510 based Bluetooth dongles

Moreover, the Devuan installation is very minimal and consists of a barebones
Devuan base, plus crucial command-line tools, like those required to connect to
a WiFi network.

Dependencies
============

Devsus has been tested on Devuan 2 (ASCII) on x86_64, with the following
packages installed:

	apt install --no-install-recommends --no-install-suggests \
		parted cgpt \
		git gawk device-tree-compiler vboot-kernel-utils gcc-arm-none-eabi \
			u-boot-tools \
		gcc make libc-dev wget g++ cmake \
		binfmt-support qemu-user-static debootstrap \
		bc wget xz-utils m4

Building
========

	# ./devsus.sh

This produces two Devuan disk images:

	1) devuan-ascii-c201-libre-16GB.img, a 16 GB image suitable for persistent
	   installation; its size should be exactly the size of the internal SSD
	2) devuan-ascii-c201-libre-2GB.img, a 2 GB image suitable for booting the
	   laptop off USB

Usage
=====

To produce a bootable media, write the 2 GB image to a flash drive (of at least
2 GB):

	# dd if=$SOMEWHERE/devuan-ascii-c201-libre-2GB.img of=/dev/$DEVICE bs=50M

The root password is blank.

The 2 GB image (yes, the smaller one) contains the larger, 16 GB one under /.
This way, it is possible to boot the laptop through USB, then install Devuan
persistently without having to download or store the large image separately.

Persistent installation is performed using dd, too:

	# dd if=/devuan-ascii-c201-libre-16GB.img of=/dev/mmcblk0

Modifications
=============

The images produced by Devsus are very close to stock Devuan:

	- APT has been configured not to install "recommended" packages by default
	- Some critical (like udev) or useful (like iw) packages have been added
	- unscd has been added, to cache DNS
	- The number of virtual consoles has been reduced from 6 to 2

Credits and Legal Information
=============================

Devsus' previous kernel building procedure was based on the linux-veyron package
of Arch Linux ARM (http://www.archlinuxarm.org/).

Devsus' workaround for ath9k_htc instability issues has been adopted from
PrawnOS (https://github.com/SolidHal/PrawnOS) and found by SolidHal.

Devsus is free and unencumbered software released under the terms of the GNU
General Public License, version 2; see COPYING for the license text. For a list
of its authors and contributors, see AUTHORS.

The ASCII art logo at the top was made using FIGlet (http://www.figlet.org/).