;; This is an operating-system configuration template of a
;; 64-bit minimal system for a Raspberry Pi with an NFS root file-system.

;; It neither installs firmware nor device-tree files for the Raspberry Pi.
;; It just assumes them to be existing in boot/efi in the same way that some
;; UEFI firmware with ACPI data is usually assumed to be existing on PCs.

;; It expects the boot/efi directory to be served via TFTP and the root
;; file-system to be served via NFS. See the grub-efi-netboot-bootloader
;; description in the manual for more details.

(use-modules (gnu)
             (gnu artwork)
             (gnu system nss))
(use-service-modules admin
                     avahi
                     networking
                     ssh)
(use-package-modules certs
                     linux
                     raspberry-pi
                     ssh)

(define %my-public-key
  (local-file (string-append (getenv "HOME") "/.ssh/id_ecdsa.pub")))

(define-public raspberry-pi-64-nfs-root
  (operating-system
   (host-name "raspberrypi-guix")
   (timezone "Europe/Berlin")
   (bootloader (bootloader-configuration
                (bootloader grub-efi-bootloader-chain-raspi-64)
                (targets (list "/boot/efi"))
                (theme (grub-theme (resolution '(1920 . 1080))
                       (image (file-append
                               %artwork-repository
                               "/grub/GuixSD-fully-black-16-9.svg"))))))
   (kernel-arguments '("ip=dhcp"))
   (kernel (modify-linux #:linux linux-libre-arm64-generic
                         #:extra-version "arm64-generic-netboot"
                         #:configs '("CONFIG_NFS_SWAP=y"
                                     "CONFIG_USB_USBNET=y"
                                     "CONFIG_USB_LAN78XX=y"
                                     "CONFIG_USB_NET_SMSC95XX=y")))
   (initrd-modules '())
   (file-systems (cons* (file-system
                         (mount-point "/")
                         (type "nfs")
                         (device ":/export/raspberrypi/guix")
                         (options "addr=10.20.30.40,vers=4.1"))
                        %base-file-systems))
    (swap-devices
     (list
      (swap-space
       (target "/run/swapfile"))))
   (users (cons* (user-account
                  (name "pi")
                  (group "users")
                  (supplementary-groups '("wheel" "netdev" "audio" "video"))
                  (home-directory "/home/pi"))
                 %base-user-accounts))
   (packages (cons* nss-certs
                    openssh
                    %base-packages))
   (services (cons* (service avahi-service-type)
                    (service dhcp-client-service-type)
                    (service ntp-service-type)
                    (service openssh-service-type
                             (openssh-configuration
                              (x11-forwarding? #t)
                              (authorized-keys
                              `(("pi" ,%my-public-key)))))
                    %base-services))
   (name-service-switch %mdns-host-lookup-nss)))

raspberry-pi-64-nfs-root