USB Keyboard not available for GRUB encrypted /boot on Le Potato

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1

When using the Le Potato, is it possible to use a USB keyboard to enter the password for an encrypted /boot when using GRUB?

My setup is:

  • I’m building u-boot and flashing it to my microSD card as describe in the u-boot docs.
  • I then setup encrypted partitions for full disk encryption with GRUB as described in the Arch Linux wiki.
  • Then I install Debian using debootstrap and configure GRUB.

I can enter the password over UART, and everything works great.

But, I haven’t been able to get a USB keyboard to work, so I can’t just plug in HDMI and my keyboard and boot normally. I’ve tried adding “usb usb_keyboard ohci uhci ehci” to GRUB_PRELOAD_MODULES, and I’ve tried doing the equivalent to u-boot’s config when building it.

Am I missing something? Or is it just impossible to bring up a USB keyboard at this stage in the boot process on the le potato?

2

You should just use our bootloader and not build your own. GRUB runs as an UEFI application so it supports UEFI input devices (USB keyboard and UART).

3

Does that mean I can build u-boot using your fork of u-boot, and that your fork has the necessary changes that are not in the upstream repo?

EDIT: Flashing the bootloader with the libretech-flash-tool does indeed work, but I’d still prefer to build it myself.

4

See How to Build Your Own Bootloader for Libre Computer Boards