Best way to remotely control bootup on a librem mini?

Hello. I own a librem mini. After a while it becomes a bit annoying to manually go to and use the actual display and physical keyboard to confirm a new checksum on my /boot when i confirm the resigning of the boot partition. Having to physically get up and move to fix a system is weird.

I would like remote control for hopefully coreboot and definitely grub.

I am likely going to have another linux machine next to the librem mini, a router running dd-wrt.

I realize i can buy a network kvm and hook it up to the hdmi output, but it’s a bit expensive. There are also dedicated setups that forward hdmi over the network, but i think they require a receiver to use an actual hdmi port and do not send any protocol like vnc.

I noticed there are lots of features of coreboot for debugging output over usb, serial, etc. I also noticed lots of network features for the different librem dev kits. I don’t have a dev kit but i’m willing to buy a piece of hardware for this purpose if it’s not too expensive.

It looks like coreboot and grub seem to both support some kind of usb debugging cable interface.

Will these work for me if i get the right cable? Has anyone set this up? Are there any better ideas?

Thank you


I’d go with something like this compared to normal KVM a rather cheap option.
You might even be able to just use a HDMI capture card combined with a keyboard emulator plunged into your router to do that.

Hm. Thanks for the tips, I have been looking into them.

I may be able to get away with just a cheap hdmi capture like used in the Pikvm. Do you know of a good way to do the keyboard emulation? I didn’t really see a way to emulate a usb keyboard device without using something like a pi. Searching for devices I didn’t find a good one. Ideally it would be just a device that one system sends commands to and the other sees as a usb keyboard. Looking for the cheapest thing and the least amount of effort. The other thing I could do is just add a usb bluetooth module to the ddwrt router (I don’t think it has Bluetooth) and put one of those Bluetooth usb keyboard receiver things on the mini.

I might make something with pi zero and just a keyboard gadget as pi zero is $5. I was thinking, to start, a one way cable with one side talking to the pi on its dev board pins and the other side connected to the pi USB port

you might be able to shave off 1$ from the hardware bill by using a pi pico with one of the UARTs connected to the ddwrt router to receive the commands and then send them to the mini via USB.