Our motherboard does not have a built-in video card. In fact, the booting from the USB flash worked but the data was not output to the console.

Helped inclusion in the Coreboot cfg file Payload-> Add SeaBIOS sercon-port file to CBFS

чт, 21 мар. 2019 г. в 16:56, Kevin O'Connor <kevin@koconnor.net>:

On Wed, Mar 20, 2019 at 01:32:27PM -0000, dponamorev@gmail.com wrote:
> Siabios did not boot debian from USB flash. Booting from the hard disk is normal. What siabios settings can affect this behavior? USB boot flash file system is FAT32.
>
> Log:
[...]
> Booting from Hard Disk...
> Booting from 0000:7c00

At this point, the bootloader is running. If the bootloader is not
functioning correctly, it would require diagnosing that code.

-Kevin