buildroot/board/synopsys/hsdk/genimage.cfg

image boot.vfat {
  vfat {
    files = {
      "uImage"
    }
    file uboot.env {
      image = "uboot-env.bin"
    }
  }
  size = 20M
}

image sdcard.img {
  hdimage {
  }

  partition boot {
    partition-type = 0xC
    bootable = "true"
    image = "boot.vfat"
  }

  partition rootfs {
    partition-type = 0x83
    image = "rootfs.ext4"
  }
}