Steam deck, dualboot manjaro?

has anybody succesfully installed manjaro or another distribution as dualboot system on the steam deck ?
i want to keep steamos as its obviously highly optimiced for gaming on the steam deck.
and want to install manjaro as steamos is readonly and only allows flatpak.
so i would love to use the steam deck as an portable audio platform.
i would try myself but haven’t bought one yet.

Ask @codesardine, he’s been fiddling with Manjaro on a Steam Deck.

thank you (again) Yochanan.

You can use the deck for anything you like it all depends on the software you install, it is the same as mini PC, you can boot manjaro from a SD card, that is very slow unless you got a fast SD card, I use it as a desktop machine to replace my old desktop and have replaced steamos with manjaro, the cheapest version will only hold steamos and you would have any space for games, using it as a portable device for anything else as a gaming console is not possible unless you have a keyboard and mouse and very good eyes as very few Linux software is done for a small touchscreen.

thank you codesardine for the detailed answer !
great to hear that manjaro runs on the steam deck.
i was worried that some parts (thumbsticks, internal soundcard, touchpads, buttons) are not working because i read steamos has its own kernel which is only available through steams repository (?).
one last question about the fan with manjaro. how does it behave on idle, is it always on ? i read it took a lot of tweeks and updates on steamos.

To be honest I did not look at the fan but I can’t hear it, but sound does not work as it’s not in upstream kernel yet.

The controller works well and can be even used as a touchpad, the gyro I also have not look into to that yet.

I am using manjaro kernel and not steamos kernel.

To be honest I did not look at the fan but I can’t hear it,

that sounds good

but sound does not work as it’s not in upstream kernel yet.

there is no driver module ? so we have to wait till it goes from steamos repository to arch and then to manjaro ?

The controller works well and can be even used as a touchpad, the gyro I also have not look into to that yet.

and those two touchpads ?

I am using manjaro kernel and not steamos kernel.

thank you !

Touchpads work and any other button or controller and the deck, I am using right touchpad as mouse, as for sound drivers we have to wait for valve to commit the drivers in the kernel upstream, we don’t have to wait for arch manjaro has its own kernels, however I have no idea when valve would do that, I know that they already pushed upstream some code and probably will push some more when they deem it ready another option would be to use valve kernel, that does not interest me but might interest you all you need to do is download it from valve repos and install it, however I have not tested that and don’t know how it will behave on manjaro.

i installed manjaro kde on sdcard (U3,A2).
at first sight everything went smoothly.
with kernel 6.0.8-1 comes the audio drivers (kernel 6.1.0rc4-1 didn’t work).

  • acp5x Playback/Capture nau8821-hifi-0
  • acp5x CS35L41 Stereo Playback multicodec-1

then installed manjaro-pipewire with wireplumber, qpwgraph, pavucontrol, jack etc.
with pavucontrol i turned the “rembrandt radeon…” off and set the “acp / acp3x…” to “pro audio”
now you have actually two sound devices one for the speakers and one for headphone.
sadly the controllers (sticks touchpad etc.) are not realy usable with rawhid. but with sc-controller comes a very nice and versatile but cpu hungry (10%) configration tool that outputs “/dev/input/js0”.

all my attempts (with steam kernel (linux-neptune) and repos) to reproduce the setup of the steamos desktop with automatic switch between headphone and speakers ended up in complete reinstalls. also one can easiely messup the acp5x configuration with alsamixer.

now im really stuck with a problem that appears after a while and i can’t find the cause.
after booting into manjaro the wifi doesen’t connect automaticaly and several kernel modules won’t load.
specially: uinput (needed for steams controller) and snd_seq (midi support, i am using steam deck as audio device, synthesizers etc.).
the not loaded modules i could track down by comparing the outputs of lsmod with working and faulty installs:

  • uinput
  • snd_seq
  • blake2b_generic
  • btrfs
  • libcrc32c
  • raid6_pq
  • snd_hrtimer
  • snd_seq_device
  • snd_seq_dummy
  • xor

i can load those by hand with pkexec modprobe uinput, pkexec modprobe snd-seq-midi but still some stuff is missing.
when this appears it stays permanently and i have to reset to the last working timeshift snapshot.
i wonder if its possible that steamos (with its unusual mechanics) affects manjaros system (like parallel windows installs used to do) as the sdcard is automaticaly mounted when booting steamos ?
one message of journalctl -b :
systemd-tmpfiles[288]: Detected unsafe path transition / (owned by user) → /dev (owned by root) during canonicalization of /dev.

@codesardine did you replace steamos with manjaro, or in parallel ?
if in parallel. on disk or sdcard ?
if on disk. does steamos mount extra partitons automaticaly like sdcard ?
i switch the os with steams bootmanager (vol down + power)
i checked the whole thing also with endeavouros and booting into steam certianly affects parallel os on sdcard with the phenomens i described earlier. comparing the affected os with rsync backups (rsync -aAXvni) doesent show anything.
so maybe its a kind of flag set by steamos ?

I have replaced steamos and use a bluetooth device for sound and gamescope session from the AUR, you can copy udev rules from steamos to make controllers work but you don’t need those if using gamescope session only in desktop session.

thank you @codesardine
i think i found the cause why manjoro getting messed up after booting steamos:

chown 1000:1000 -- "${MOUNT_POINT}"

in /usr/lib/hwsupport/, line 83, function do_mount()
any sdcards root is getting changed to owner uid 1000.

chown root:root / seem to fix it.
i would change that line but it probably will be reverted with the next steamos update.
so is there a way to chown root:root / back in a very early state of manjaros boot process ?

Maybe try to set it in your login manager and see if that works for your use case, I know that lightDM allows this before or after we login, others I don’t know you will have to dig in the documentation.

I am sure you can load earlier then that but not before boot process is finished but you will have to change core files that will still be overriden with a update.

Regarding this I would just do my own session with any needed modified scripts, and load whatever is needed, It does not need to be complex.

I don’t understand if you are running steamOS or manjaro, but i never had any partition interfere with a different installation ever.

@spikerguy is working on a KDE image for handheld not sure how far he is going or if the image is ready for public testing I think is in alpha stage. Maybe he is so kind to let you test it, this image is not specific for the steam deck tho.