# Milk-V Mars boot media

`make boot_image TARGET=MILKV` builds `build/boards/milkv/lithos-milkv.img`: a GPT disk with one
FAT32 EFI System Partition. Write it to an SD card with `dd`. The partition holds:

- `EFI/BOOT/BOOTRISCV64.EFI`: the riscv64 monolithic loader, the same one QEMU boots.
- `startup.nsh`: for a UEFI shell, if one is used.
- `starforth.cfg`: only present when `KERNEL_ARGS="..."` is given.

The board's own SPI-flash U-Boot, with OpenSBI underneath, finds the loader through its standard
`bootefi` scan of the removable-media path. U-Boot passes its devicetree to the loader through the
EFI configuration table.

Status: booted in QEMU through the same chain the board uses: OpenSBI, then U-Boot
`qemu-riscv64_smode`, then `bootefi` from this image's ESP, then the loader and the kernel. POST
passed, Stadium conservation was exact (resident 43691 + reservoir 21845 = 65536 = `Q48_ONE`), and
Hestia and Artemis came up. Not yet booted on the Mars itself. The JH7110 peripherals
(framebuffer, RNG) have only been checked by compiling.

To repeat the QEMU boot (`qemu-system-riscv64` is in Ubuntu 26.04's `qemu-system-riscv` package;
OpenSBI and U-Boot come from `opensbi` and `u-boot-qemu`). Use a copy, because the kernel writes
to its disk:

```
cp build/boards/milkv/lithos-milkv.img /tmp/mv.img
qemu-system-riscv64 -machine virt -cpu rv64 -m 2048 -nographic \
    -bios /usr/lib/riscv64-linux-gnu/opensbi/generic/fw_dynamic.bin \
    -kernel /usr/lib/u-boot/qemu-riscv64_smode/u-boot.bin \
    -drive if=none,format=raw,file=/tmp/mv.img,id=d0 -device virtio-blk-device,drive=d0
```