Console access without USB-TTY or network

My HiKey960 board has recently stopped to attach to Wifi network and I cannot log in (with ssh) to a terminal.
Meantime the system seems alive.
Is there any other way to log in to console? Can I do this with USB-C?

If you were running Android, you would be able to use ADB, but since you’re talking about SSH, I imagine that you’re probably not using Android.

That means that your only options are going to be;
Network; you’ve apparently tried and failed,
Direct; i.e., keyboard and monitor,
UART; it connects to a few of the pins on the low speed header.

You’re right, board is running debian.
I forgot about keyboard and monitor, I’ll try this way, thanks!

Wondering whether usb-c is functional in debian and, if yes, is there any way to configure it somehow so that the board is providing tty over it (perhaps, I could configure it if I’ll get an access with keyboard)?

It is certainly possible to set up another form of console via the USB.

If you want to use the USB-C, then it would have to be by way of a gadget driver. It would probably be easier, however, to use a device connected to one of the USB-A ports.

Note that the Kirin 960 only has a single USB port, which is routed EITHER to the hub (and the A ports), or to the C port. They can’t all work at the same time. The Dragonboard 820C is much better in this area, since that SoC has multiple USB ports, allowing the device and host ports to all work at the same time.