To test the kernel, I recommend to start with uuu.
This script will boot a given kernel: https://source.puri.sm/Librem5/librem5-devkit-tools/-/blob/pureos/byzantium/uuu_scripts/boot_librem5.lst
I appreciate you take the time to reply, but from my original message it should be quite obvious that I am using uuu.
In the mean time I’ve discovered that the Linux kernel source from https://source.puri.sm/Librem5/linux does produce a booting kernel so some essential code seems not available in upstream.
I’m trying to build a module-less variant to boot NixOS with.
With “build Jumpdrive”, you also mean the kernel? If yes, I assume you we not using upstream kernel as your source?
Oh, sorry. I only looked at the most recent message. Anyway, I think you know as much as I do now.
1 Like
Yes
Correct. git cloned from something on source.puri.sm
1 Like
I’ve managed to get NixOS running on the Librem 5 with a kernel build from https://source.puri.sm/Librem5/linux.git
Biggest issue atm is that I do not have sound in calls due to callaudiod segfaulting.
One of the minor issues that I have to run mkimage by hand to update /boot/boot.scr on configuration changes, to to boot into a new NixOS environment. It seems Purism u-boot does not support u-boot’s Generic Distro Configuration Concept which supports /boot/extlinux/ extlinux.conf: https://u-boot.readthedocs.io/en/latest/develop/distro.html
The part in /etc/nixos/configuration.nix that builds the Purism kernel is:
boot = {
initrd = {
kernelModules = [ "bq25891_charger" "dwc3" "imx_dcss" "imx_sdma" "mtdblock" "ofpart" "phy_fsl_imx8mq_usb" "snvs_pwrkey" "spi_nor" "tps6598x" "xhci_hcd" "usbcore" "usb_storage" "uas" "xhci_plat_hcd" ];
};
kernelParams = [ "console=tty0" "earlyprintk=vga" "ignore_loglevel" "rootwait" ];
loader = {
generic-extlinux-compatible.enable = true;
grub.enable = false;
};
kernelPackages = let
linux_librem5_pkg = { fetchgit, buildLinux, ... } @ args:
buildLinux (args // rec {
defconfig = "librem5_defconfig";
version = "6.1.6-librem5";
modDirVersion = version;
src = fetchgit {
url = "https://source.puri.sm/Librem5/linux.git";
hash = "sha256-EE6WHqgBmoRuZnbCPO3NrydOHPxG8G7lZXxDNm/2Kq4=";
};
kernelPatches = [];
} // (args.argsOverride or {}));
linux_librem5 = pkgs.callPackage linux_librem5_pkg{};
in
pkgs.recurseIntoAttrs (pkgs.linuxPackagesFor linux_librem5);
};
3 Likes
Perhaps this merge request may be of interest to you:
If it is we can share here how to install it.
2 Likes
Also do you have the mandatory screenshot of it running NixOS 
That seems exactly what is needed! Please share 
Will create 
Well…
On a debian based system…
You would download the .deb package from here;
install it with:
sudo apt install ./u-boot-librem5_2022.10-librem5.1_arm64.deb
then run sudo u-boot-install-librem5 /dev/mmcblk0
1 Like
$ curl -LOC - https://source.puri.sm/a-wai/uboot-imx/-/jobs/405334/artifacts/raw/debian/output/u-boot-librem5_2022.10-librem5.1_arm64.deb
$ ar -x u-boot-librem5_2022.10-librem5.1_arm64.deb
$ tar xf data.tar.xz
$ cat usr/bin/u-boot-install-librem5
$ sudo dd if=/dev/zero of=/dev/mmcblk0 bs=1024 count=1055 seek=2
$ sudo dd if=usr/lib/u-boot/librem5/u-boot.imx conv=notrunc of=/dev/mmcblk0 bs=1024 seek=33
I’ll need to verify and execute this.
edit: this works, thanks! 
3 Likes
I’ve revived my Librem 5 after it has been laying on my desk for months - plugged in once a week to prevent the battery from draining to zero - after a failed u-boot update, and wanted to finally follow up to your request:
[ookhoi@librem5:~]$ nix run -- nixpkgs#screenfetch
::::. '::::: ::::' ookhoi@librem5
'::::: ':::::. ::::' OS: NixOS 24.11.20241001.e277415 (Vicuna)
::::: '::::.::::: Kernel: aarch64 Linux 6.6.52-librem5
.......:::::..... :::::::: Uptime: 1h 25m
::::::::::::::::::. :::::: ::::. Packages: 1306
::::::::::::::::::::: :::::. .::::' Shell: bash 5.2.32
..... ::::' :::::' Disk: 11G / 30G (38%)
::::: '::' :::::' CPU: Unknown @ 4x 1.5GHz
........::::: ' :::::::::::. GPU:
::::::::::::: ::::::::::::: RAM: 682MiB / 2888MiB
::::::::::: .. :::::
.::::: .::: :::::
.::::: ::::: ''''' .....
::::: ':::::. ......:::::::::::::'
::: ::::::. ':::::::::::::::::'
.:::::::: '::::::::::
.::::''::::. '::::.
.::::' ::::. '::::.
.:::: :::: '::::.
Not much installed yet.
5 Likes
I’m curious about your experience so far. Does everything work as much as it does on PureOS? Have you been using it on a daily basis?
1 Like
That would be wild, you gave me a really stupid idea using the dev pinout, a 3D printer and a few other things… Imagine a backplate that gives yiu a serial interface RS-232 (the DB connector that is smaller than the other RS-232 connector (which looked like a centronics parallel port). Techincally doable with the breakout board and pogo pins.
1 Like
…or you could just use the USB-C port:
…or you could use the extension connector:
This one is even available to buy from Purism:
[edit] I missed the implied non-seriousness of your post, but I’ll leave these links here in case other people find them useful 
4 Likes
I think I have a box of male 3 pin ATP connectors somewhere in my attic. They were exclusive to Hewlett Packard for RS-232. About the same size as DB9 connectors but with a squeeze plastic locking mechanism.
2 Likes
I’m afraid I’m not using my Librem 5 at all. It is just too slow and too limited to spark joy.
Sound in calls and the camera don’t work with NixOS. Although I expect both can work with some effort.
All other software available for aarch64 works (currently running gnome).
I do play with the Librem 5 now and then. I’ve just reinstalled on a single partition to see if is feasible, to eliminate the trouble of planning disk layout during installation. And it is:
[ookhoi@librem5:~]$ sudo fdisk -l /dev/mmcblk0
Disk /dev/mmcblk0: 29.12 GiB, 31268536320 bytes, 61071360 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: FCC00EA4-5943-4056-878B-17D8D388CAFA
Device Start End Sectors Size Type
/dev/mmcblk0p1 4096 61071326 61067231 29.1G Linux filesystem
[ookhoi@librem5:~]$ df -h / /boot/
Filesystem Size Used Avail Use% Mounted on
/dev/mmcblk0p1 29G 17G 11G 63% /
/dev/mmcblk0p1 29G 17G 11G 63% /boot
What I dislike most about the Librem 5 is that there is no upstream support. I’m stuck with the ancient kernel versions that Purism provides - currently 6.6.74 - with no prospect that the Librem 5 will ever be a truly libre Linux device.
I am thankful for all Purism has done for Linux on mobile.
How is your experience with PureOS on Librem 5?
edit:
[ookhoi@librem5:~]$ nix run -- nixpkgs#screenfetch
::::. '::::: ::::' ookhoi@librem5
'::::: ':::::. ::::' OS: NixOS 25.05.20250311.b62d2a9 (Warbler)
::::: '::::.::::: Kernel: aarch64 Linux 6.6.74-librem5
.......:::::..... :::::::: Uptime: 2h 9m
::::::::::::::::::. :::::: ::::. Packages: 1442
::::::::::::::::::::: :::::. .::::' Shell: bash 5.2.37
..... ::::' :::::' Disk: 17G / 29G (63%)
::::: '::' :::::' CPU: ARM Cortex-A53 @ 4x 1.5GHz
........::::: ' :::::::::::. GPU:
::::::::::::: ::::::::::::: RAM: 964MiB / 2890MiB
::::::::::: .. :::::
.::::: .::: :::::
.::::: ::::: ''''' .....
::::: ':::::. ......:::::::::::::'
::: ::::::. ':::::::::::::::::'
.:::::::: '::::::::::
.::::''::::. '::::.
.::::' ::::. '::::.
.:::: :::: '::::.
3 Likes
Thanks a lot for the response. It seems like a dealbreaker that calls and camera don’t work on it.
I haven’t used Librem 5 with NixOS, but was considering it. Hence I asked.
Btw, there was a discussion about extending ZRam, which seems to greatly improve responsiveness and performance: Why and how to extend ZRAM on L5. A revolution for Librem 5 stability! - #65 by shak
Maybe you can try that?
1 Like