my experiences with raspberry 1 and using u-boot:

1.  Get https://files.devuan.org/devuan_ascii/e … pi1.img.xz
or from
https://files.devuan.org/devuan_ascii.torrent

2. on raspi 1:

sudo apt-get install u-boot u-boot-rpi linux-image

sudo cp /usr/lib/u-boot/rpi/u-boot.bin /boot/

echo kernel u-boot.bin >> /boot/config.txt

sudo apt-get install u-boot-menu
sudo mkdir /boot/extlinux/; sudo touch /boot/extlinux/extlinux.conf
edit /etc/default/u-boot, especially U_BOOT_PARAMETERS whitch corresponds to /boot/cmdline.txt

finally:
sudo u-boot-update