Can someone with serial console access try NixOS kernel on Librem 5?

Hardware Librem 5
1

Can someone with serial console access on Librem 5 (or devkit?) try to boot these aarch64 NixOS kernel, initrd and dtb, and let me know what error it gives?

https://humilis.net/u-boot-librem5.bin
https://humilis.net/nixos-linux-6.1.2-image
https://humilis.net/nixos-linux-6.1.2-initrd
https://humilis.net/imx8mq-librem5-r4.dtb

boot-nixos-with-uuu.lst:

uuu_version 1.0.1
CFG: FB:  -vid 0x316d -pid 0x4c05
CFG: SDP: -chip MX8MQ -compatible MX8MQ -vid 0x316d -pid 0x4c05

SDP: boot -f u-boot-librem5.bin
SDPU: delay 1000
SDPU: write -f u-boot-librem5.bin -offset 0x57c00
SDPU: jump

SDPV: delay 1000
SDPV: write -f u-boot-librem5.bin -skipspl
SDPV: jump

SDPS: boot -f u-boot-librem5.bin
SDPS: delay 1000

FB: ucmd setenv bootargs earlyprintk=vga console=tty0 ignore_loglevel

FB: ucmd setenv fastboot_buffer 0x40000000
FB: download -f nixos-linux-6.1.2-image
FB: ucmd setenv fastboot_buffer 0x44000000
FB: download -f imx8mq-librem5-r4.dtb
FB: ucmd setenv fastboot_buffer 0x44800000
FB: download -f nixos-linux-6.1.2-initrd

FB: acmd booti 0x40000000 0x44800000:${fastboot_bytes} 0x44000000
FB: Done

uuu -v boot-nixos-with-uuu.lst

This is the hardest ARM device I’ve ever encountered :slight_smile:

I’ve spend the past two weeks trying to boot NixOS, and self-compiled barebox and u-boot on my Librem 5. As Librem 5 has no serial console port - https://puri.sm/posts/avoid-boot-loops-try-librem-5-serial/ - trying boot software is a matter of trial and error. (Purism, please include a serial port on the next version).

barebox might not support Librem 5: closest I found was for i.MX8MP-EVK: https://www.barebox.org/doc/latest/boards/imx/nxp-imx8mp-evk.html
This produces barebox-nxp-imx8mq-evk.img but seems not bootable.

u-boot seems to support Librem 5: https://u-boot.readthedocs.io/en/latest/board/purism/librem5.html
but these build instructions seem way too limited compared to the Purims u-boot build script: https://source.puri.sm/Librem5/u-boot-builder/-/blob/librem5/build_uboot.sh

Last resort was using kexec but:

purism@pureos:~$ sudo kexec -l /boot/nixos/ch4w8c2x2i9l5hr2q9013a8ajl64yniv-linux-6.1.2-Image
[sudo] password for purism:
Can't open (/proc/kcore).
Can't open (/proc/kcore).
kexec_load failed: Function not implemented
entry       = 0x437af690 flags = 0xb70000
nr_segments = 3
segment[0].buf   = 0xffffbafd6010
segment[0].bufsz = 0x36d0a00
segment[0].mem   = 0x40000000
segment[0].memsz = 0x37a0000
segment[1].buf   = 0xaaaafd1a1d10
segment[1].bufsz = 0xe080
segment[1].mem   = 0x437a0000
segment[1].memsz = 0xf000
segment[2].buf   = 0xaaaafd1b02d0
segment[2].bufsz = 0x3460
segment[2].mem   = 0x437af000
segment[2].memsz = 0x4000

purism@pureos:~$ zgrep KEXEC /proc/config.gz
# CONFIG_KEXEC is not set
# CONFIG_KEXEC_FILE is not set
2

Did you see https://source.puri.sm/Librem5/community-wiki/-/wikis/hardware/Serial-Console ?

I don’t say it’s easy…

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3

I had not :slightly_smiling_face: Thanks for the link!

I’m not comfortable making hardware modifications to my Librem 5. I would have bought a devkit if that was still available. Or maybe a spare Librem 5 board when that gets available.

edit: actually the first solution does not require hardware modifications to Librem 5

4

Yes and that makes it so interesting. But nobody yet found a different, cheaper dock than the Dell one.

Depending on where you’re based I might be able to help you with mine…

1 Like
5

:open_mouth:
You have all hardware required for serial console access?? I live in Arnhem. I’m currently compiling a kernel for Librem 5 with kexec enabled. If that does not enable me to boot a NixOS kernel and no one follows up on my request your offer could be my last resort to get NixOS on my phone :hugs:

6

I’m trying to wrap my head conceptualizing a 25 or 9 pin RS-232 serial connector on a phone.

1 Like
7

Nobody uses RS-232 any more. It’s all UART over TTL.

8

You just don’t see the humor in it.

9

I do, and I recoil :stuck_out_tongue:

1 Like
10

I was trying to picture an L5 with the old 25 pins parallel printer connector. :laughing:

To be serious: there are USB to serial adapters, I used to use them when configuring switches at the console port. They where a pain in the a## . When they worked all was fine, but to get them going was always a nightmare.

11

You not say :slightly_smiling_face:

On the subject of connecting All The Things™ to a phone:

12

On this picture, it’s the phone that’s attached to the thing…

13

So downloaded kernel source linux-6.2-rc2, copied contents of Librem 5 /proc/config.gz to .config, edited to enable KEXEC and compiled the kernel on an rpi4 just to be sure arch-wise.

Much to my surprise the resulting kernel does not boot. The led even switches off.

Do the kernels need to be signed for some kind of secure boot or something?

14

I would say “no”, both because that totally gets away from Purism’s approach and because I was able to build Jumpdrive from sources and boot it on my Librem 5 (which wouldn’t work if anyone other than I was needed to sign the resulting kernel).

1 Like
15

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

16

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.

17

With “build Jumpdrive”, you also mean the kernel? If yes, I assume you we not using upstream kernel as your source?

18

Oh, sorry. I only looked at the most recent message. Anyway, I think you know as much as I do now.

1 Like
19

Yes

Correct. git cloned from something on source.puri.sm

1 Like
20

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);
};
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