How to actually describe MBR partition table?

[RadxaYuntian]

Amlogic based devices must use MBR partition table, as their bootloader will overlap with GPT partition table. However, when I used type = "table", I got the infamous read-only error. What option do I have here?

(Yes this layout is mirroring GPT EFI layout because U-Boot will boot EFI bootloader found on a MBR disk.)

{
  disko.devices = {
    disk = {
      main = {
        device = "/dev/disk/by-id/TARGET-DEVICE";
        type = "disk";
        content = {
          type = "table";
          format = "msdos";
          partitions = [
            {
              name = "ESP";
              start = "16M";
              end = "516M";
              bootable = true;
              content = {
                type = "filesystem";
                format = "vfat";
                mountpoint = "/boot";
              };
            }
            {
              name = "root";
              start = "516M";
              end = "100%";
              content = {
                type = "filesystem";
                format = "btrfs";
                mountpoint = "/";
                mountOptions = [ "compress=zstd" ];
              };
            }
          ];
        };
      };
    };
  };
}