gistfile1.txt

~/tmp/tmp $ nix-shell -I nixpkgs=$HOME/tmp/nixpkgs/nixpkgs -p 'pkgsCross.aarch64-embedded.buildUBoot{defconfig = "orangepi_zero_plus2_defconfig"; extraMeta.platforms = ["aarch64-none"]; BL31 = "${pkgsCross.aarch64-multiplatform-musl.armTrustedFirmwareAllwinner}/bl31.bin";filesToInstall = ["u-boot-sunxi-with-spl.bin"];}'

[nix-shell:~/tmp/tmp]$ sudo dd if=/dev/zero of=/dev/sdg bs=1024 seek=8 count=1024
1024+0 records in
1024+0 records out
1048576 bytes (1.0 MB, 1.0 MiB) copied, 0.479617 s, 2.2 MB/s

[nix-shell:~/tmp/tmp]$ sudo dd if=$buildInputs/u-boot-sunxi-with-spl.bin of=/dev/sdg bs=1024 seek=8
562+1 records in
562+1 records out
575672 bytes (576 kB, 562 KiB) copied, 0.27881 s, 2.1 MB/s

[nix-shell:~/tmp/tmp]$ sudo eject /dev/sdg