Add allwinner sbc installation script

bin/install-sd-allwinner

+#!/usr/bin/env zsh
+
+set -e
+set -u
+set -x
+set -o pipefail
+
+source $DOTFILES_PATH/bin/lib/util.zsh
+
+cmdname=$(basename $0)
+usage() {
+  print "Usage: $cmdname <machine>" >&2
+}
+readonly machine="$1"
+
+# Update nar-hash of dotfiles repository
+nix flake lock --update-input dotfiles "path:$MACHINES_PATH"
+
+readonly nix=(nix --log-format bar-with-logs)
+
+# Installables
+readonly uboot_installable="path:$MACHINES_PATH#nixosConfigurations.$machine.config.system.build.u-boot"
+readonly system_installable="path:$MACHINES_PATH#nixosConfigurations.$machine.config.system.build.toplevel"
+
+# Build once to catch errors
+$nix build --no-link $uboot_installable
+$nix build --keep-going --no-link $system_installable
+
+
+# Use cached build to get output path
+readonly nixos_config_path=$($nix build --json --no-link $system_installable | jq --raw-output ".[0].outputs.out")
+
+
+# NOTE: Update if required
+readonly target_disk="/dev/disk/by-id/usb-Generic_MassStorageClass_000000001538-0:1"
+
+# NOTE: Update for each new installation
+readonly root_partition_uuid="184a74e1-894b-4319-b9c9-9b0f972a30f8"
+
+# NOTE: Update for each new installation
+readonly root_uuid="dec6d7a8-6f97-4f4e-aaeb-98fd1e6bda27"
+
+
+# Derived paths
+readonly root_partition="/dev/disk/by-partuuid/$root_partition_uuid"
+
+
+sudo wipefs -a $target_disk
+
+# 2MB header hole
+sudo nix shell nixpkgs#vboot_reference -c cgpt create -p 4096 $(realpath $target_disk)
+sudo nix shell nixpkgs#vboot_reference -c cgpt boot -p $(realpath $target_disk)
+
+sudo nix shell nixpkgs#util-linux -c sfdisk $target_disk --append <<EOF
+  unit: sectors
+  sector-size: 512
+
+  start=4224, type=69dad710-2ce4-4e3c-b16c-21a1d49abed3, uuid=$root_partition_uuid, name="root"
+EOF
+
+
+nix shell nixpkgs#busybox -c partprobe
+
+# Use cached build to get u-boot output path
+readonly uboot=$($nix build --json --no-link $uboot_installable | jq --raw-output ".[0].outputs.out")
+
+#sudo dd if=$uboot/u-boot-sunxi-with-spl.bin of=$uboot_partition bs=16M conv=fsync oflag=direct status=progress
+sudo dd if=$uboot/u-boot-sunxi-with-spl.bin of=$target_disk bs=1024 seek=8 conv=fsync status=progress
+
+
+sudo wipefs -a $root_partition
+
+# partprobe doesn't seem to be enough for symlinks to appear?
+while [[ ! -b $root_partition ]] {
+  print "Waiting for $root_partition"
+  sleep 1s
+}
+sudo mkfs.ext4 -U $root_uuid -L root_$machine $root_partition
+
+mount_point=/mnt/mnt
+sudo mount $root_partition $mount_point
+
+sudo $nix copy --no-check-sigs --to "$mount_point" $nixos_config_path
+
+print "Setting system profile"
+sudo nix-env --store $mount_point --profile $mount_point/nix/var/nix/profiles/system --set $nixos_config_path
+
+print "Creating /etc/NIXOS"
+sudo mkdir -m 0755 -p "$mount_point/etc"
+sudo touch "$mount_point/etc/NIXOS"
+
+# Bootloader installation: broken when installing across architectures
+#sudo nixos-enter --root $mount_point -c "NIXOS_INSTALL_BOOTLOADER=1 $nixos_config_path/bin/switch-to-configuration boot"
+
+# Manual steps:
+# - open switch-to-configuration script
+# - look for "Install or update the bootloader."
+# - run extlinux-conf-builder.sh:
+#   /nix/store/[...]-extlinux-conf-builder.sh -d /mnt/mnt/boot -c $nixos_config_path -t 5
+sync