qloader2

x86/x86_64 BIOS Bootloader

Supported boot protocols

• Linux
• stivale (qloader2's native boot protocol, TODO: write specification)

Supported filesystems

• ext2
• echfs

Supported partitioning schemes

• MBR
• GPT

How to use

This repository contains a prebuilt version of qloader2 so building it won't be necessary.

In order to install qloader2 on a MBR device (which can just be a raw image file), run the provided qloader2-install script as such:

./qloader2-install ./qloader2.bin <path to device/image>

If using a GPT formatted device, it will be necessary to create an extra partition (of at least 32K in size) to store stage 2 code. Then it will be necessary to tell the install script where this partition is located by specifying the start sector.

fdisk <device>    # Create bootloader partition using your favourite method
./qloader2-install ./qloader2.bin <path to device/image> <start sector of boot partition>

Then make sure the device/image contains at least 1 partition formatted in a supported filesystem containing a qloader2.cfg file and the kernel/modules one wants to load.

An example qloader2.cfg file can be found in test/qloader2.cfg.

More info on the format of qloader2.cfg can be found in CONFIG.md.

For example, to create an empty image file of 64MiB in size, 1 echfs partition on the image spanning the whole device, format it, copy the relevant files over, and install qloader2, one can do:

dd if=/dev/zero bs=1M count=0 seek=64 of=test.img
parted -s test.img mklabel msdos
parted -s test.img mkpart primary 1 100%
echfs-utils -m -p0 test.img quick-format 32768
echfs-utils -m -p0 test.img import path/to/qloader2.cfg qloader2.cfg
echfs-utils -m -p0 test.img import path/to/kernel.elf kernel.elf
echfs-utils -m -p0 test.img import <path to file> <path in image>
...
./qloader2-install $THIS_REPO/qloader2.bin test.img

One can get echfs-utils by installing https://github.com/qword-os/echfs.

Building from source

In order to hack qloader2, one must build the GCC toolchain from source first.

To do so, run the make_toolchain.sh script from within the toolchain directory; keep in mind that the script takes MAKEFLAGS as an argument.

cd toolchain
./make_toolchain.sh -j4

After that is done, simply run make in the root of the repo to generate src/qloader2.bin.