There was a session on running guix on weird computers during this years Guix Days, and five people brought their purple colored MNT Pocket Reform laptops with them, which proves two things in my book:

• that purple undoubtedly is the best color! (all cool tech is purple, the gameboy advance, gamecube, the pocket reform!)
• … and that there's definitely growing interest in running Guix System on aarch64 machines (such as MNT laptops).

more than a week ago I wrote a post on how to install and run Guix System on the rk3588 pocket reform , so let's write another one and focus on what's still missing and what could be improved, to make running Guix System on these machines as easy as possible.

Status Overview TLDR Thingy(TM)

I had a status table living in my denote Zettelkasten for a while now to keep track the rk3588 pocket reform guix system efforts, this is a slightly modified version of it:

Recap

As a recap of my last post, we're able to run Guix System on a MNT Pocket Reform laptop, if we ignore that:

• u-boot has to be stock and has to be already present on EMMC as we can't ship rk3588 u-boot in guix just yet.
• all WiFi options offered by MNT aren't supported in linux-libre (but there are other options!)
• there's currently not a feasible way to use full disk encryption.

I think the current state is a prime example of the Pareto principle, as there's not really that much missing, even though it's difficult to make an educated guess on a timeframe when some of the things missing can be resolved.

I'd love to see parity in functionality to the stock system images by MNT for Guix System on the reform laptops and think that it's probably achievable.

1. What's Already Available In Guix Proper

Let's start with excellent news: everything to bring up a rk3588 pocket reform laptop (within the aforementioned limitations) is already there!

• a linux-libre-arm64-mnt-reform kernel variant (upstreamed by Vagrant).

• the reform2-lpc-module DKMS module for reading battery status and shutting down the reform properly from userspace (upstreamed by Arjan).

• a generic u-boot package that works well enough to generate an extlinux.conf that can be consumed by the u-boot variant the pocket reform is shipped with.

2. Things On Their Way To Guix Proper

A barebones system image definition good enough to bring up Guix System when flashed to an microSD card has been suggested as a PR for inclusion in guix proper by me. This means, that, as soon as this is merged, CI would pick up building bootable images that can be written to microSD.

3. What's Still Missing And Can Possibly Be Upstreamed

FBCON Options Enablement (Rotation etc.)

A PR to add the relevant kernel config options to enable rotation of the framebuffer console to the pocket reform kernel variants could be created. I saw the rotation issue being resolved on some devices during Guix Days, but forgot to ask which options were chosen to do this.

rk3588 U-Boot As Soon As Its Bootchain Is Fully Libre

As soon as the proprietary DDR training blob can be replaced for the rk3588 we'd be able to upstream a device-specific u-boot package. I don't know if there currently are any efforts on freeing the DDR training blob or what the progress is on this, for the time being that would remain the only blocker.

reform-tools

There's currently not a package for the reform-tools in guix and not a service for the reform-hw-setup shell script. I've been meaning to replace said shell script with a proper shepherd service covering the same functionality (right now my service calls the upstream script, but it could be guile & gexp all the way).

4. What's Currently Still Unsupported

Full Disk Encryption

There's currently not a possible way to have full disk encryption with this setup. However, using an encrypted home partition is possible and may be good enough, even though I strongly prefer being able to use FDE. There's a draft GCD on rewriting the Bootloader Subsystem to be less GRUB centric, that would maybe also allow tackling these issues easier.

The best case would be, to, instead of typing my LUKS password twice twice (sic!), be able to use a keyfile to decrypt. And, if not using a keyfile, to be actually able to see the password prompt and wether or not unlocking has succeeded (this is also an issue on my corebooted ThinkPad x230 with a FHD panel mod, my previous laptop, that I had to blindly type my password four times as the prompt wasn't displaying on screen).

I think for now I'll experiment with encrypting my /home partition, and will document my setup and the results.

Lack of FDE was seen as one of the bigger show stoppers during the Guix Days session, and I agree with that, without fully knowing what a good and possible solution could look like.

Most Available WiFi Hardware

WiFi, as almost always with any kind of modern hardware, remains to be an issue. Atheros QCNFA335 and QCNFA222 based cards will work on the Headset/Switch Board 2.0 NGFF slot, so there's at least a libre option available.

Display Support in U-Boot

There's no display support in u-boot , which means that, without using a 3.3V USB-to-UART adapter hooked up to another computer, there's not really a way to select different generations in the bootloader menu.

The December and January Update by MNT states that there's been some success with display support for barebox , so maybe, while not being able to package it for guix just yet, it could be utilizied the same way we utilize u-boot right now as a bring your own bootloader type of thing. Packaging it for Guix would suffer from the same issues as u-boot in terms of requiring proprietary blobs during the boot process.

5. Things I'll Hack On Next

Out of all aforementioned issues, I think I'll focus on the following things when I have time to spare:

• disk encryption, starting by figuring out a feasible encrypted /home set-up, working my way up to be more knowledgable about what's missing to do FDE the annoying way (typing passwords twice!).
• coming up with a hw-setup shepherd service that's not a bash script.

I'd also love to team up with people on improving support for MNT family laptops in Guix System specifically, if you want to hack on one of the mentioned things with me feel free to contact me by e-mail!