DisplayPort on a different free distro

Hello,

I have a T430 laptop where I was running Trisquel 9. I was using a second monitor through DisplayPort and that worked perfectly. It worked perfectly on both the DisplayPort of the docking station and the mini-DisplayPort of the laptop itself.

Now I am trying Guix on that laptop, I mean the Guix system, not just the package manager, but the second monitor does not work.

xrandr only shows my own laptop's screen.

If I connect my second monitor through VGA, xrandr does detect that VGA connection.

dmesg shows nothing at all when connecting to the DisplayPort port of my docking station.

However, when connecting to the mini DisplayPort port of the laptop itself, it shows this message repeatedly:

[27925.506913] nouveau 0000:01:00.0: bus: MMIO read of 00000000 FAULT at 103048 [ PRIVRING ]
[27925.506929] nouveau 0000:01:00.0: bus: MMIO write of 00000000 FAULT at 103048 [ PRIVRING ]
[27932.624065] nouveau 0000:01:00.0: bus: MMIO read of 00000000 FAULT at 103048 [ PRIVRING ]
[27932.624082] nouveau 0000:01:00.0: bus: MMIO write of 00000000 FAULT at 103048 [ PRIVRING ]
[27939.367201] nouveau 0000:01:00.0: bus: MMIO read of 00000000 FAULT at 103048 [ PRIVRING ]
[27939.367217] nouveau 0000:01:00.0: bus: MMIO write of 00000000 FAULT at 103048 [ PRIVRING ]
[27946.522991] nouveau 0000:01:00.0: bus: MMIO read of 00000000 FAULT at 103048 [ PRIVRING ]
[27946.523008] nouveau 0000:01:00.0: bus: MMIO write of 00000000 FAULT at 103048 [ PRIVRING ]
[27953.348859] nouveau 0000:01:00.0: bus: MMIO read of 00000000 FAULT at 103048 [ PRIVRING ]
[27953.348875] nouveau 0000:01:00.0: bus: MMIO write of 00000000 FAULT at 103048 [ PRIVRING ]
[27960.178545] nouveau 0000:01:00.0: bus: MMIO read of 00000000 FAULT at 103048 [ PRIVRING ]
[27960.178561] nouveau 0000:01:00.0: bus: MMIO write of 00000000 FAULT at 103048 [ PRIVRING ]
[27967.366446] nouveau 0000:01:00.0: bus: MMIO read of 00000000 FAULT at 103048 [ PRIVRING ]
[27967.366462] nouveau 0000:01:00.0: bus: MMIO write of 00000000 FAULT at 103048 [ PRIVRING ]
[27974.431155] nouveau 0000:01:00.0: bus: MMIO read of 00000000 FAULT at 103048 [ PRIVRING ]
[27974.431172] nouveau 0000:01:00.0: bus: MMIO write of 00000000 FAULT at 103048 [ PRIVRING ]
[27980.786265] nouveau 0000:01:00.0: bus: MMIO read of 00000000 FAULT at 103048 [ PRIVRING ]
[27980.786281] nouveau 0000:01:00.0: bus: MMIO write of 00000000 FAULT at 103048 [ PRIVRING ]

What should I do?

Thank you!