Buildroot External Tree

The repository provides a BR2_EXTERNAL tree at mds_external/. Buildroot picks it up automatically via the Makefile (BR2_EXTERNAL=$(EXTERNAL_REPOSITORIES)).

Layout

mds_external/
├── external.desc         # 'name: MDS' — registers the tree
├── Config.in             # Kconfig fragment, sourced into Buildroot
├── external.mk           # Make snippet, sourced into Buildroot
├── local.mk              # Optional local overrides
└── board/
    ├── mds_network_player/
    ├── mds_network_player_v2/
    ├── raspberrypizero2w/
    └── v851s_lizard/

`external.desc`

name: MDS

This name surfaces in BR2_EXTERNAL_MDS_PATH, which is used everywhere else in the tree to reference files.

Board directories

Each subdirectory under board/<machine>/ carries everything that is not a Buildroot package but needs to ship with that machine:

File	Purpose
`u-boot_defconfig`	U-Boot config for the production target
`u-boot-bootstrap_defconfig`	U-Boot config for the bootstrap image
`u-boot_devicetree.dts`	Custom DTS injected into U-Boot
`uboot.env`, `uboot.bootstrap.env`	U-Boot environment scripts
`uboot-patches/`	Patches applied on top of mainline U-Boot
`kernel_defconfig`	Linux config
`linux-patches/`	Patches applied on top of mainline Linux
`image.its`	FIT image description (kernel + DTB + initramfs)
`mknandboot.sh`	Re-packs `u-boot-with-spl.bin` for SPI NAND boot
`f1c100_uboot_spinand.sh`	Companion script for SPL relocation
`post-images.sh`	Buildroot `post-image` hook for the regular rootfs
`post-images-fota.sh`	Buildroot `post-image` hook for the FOTA initramfs
`rootfs_overlay/`	Files copied verbatim into the final rootfs
`fota_rootfs_overlay/`	Files copied verbatim into the FOTA initramfs
`boot_esp32.sh`, `flash_esp32.sh`	Helpers for the ESP32-C3 companion firmware

Editing the kernel / U-Boot config

To change the in-tree kernel config:

make build-linux-menuconfig
make build-linux-savedefconfig
cp build/output/network_player/build/linux-*/defconfig \
   mds_external/board/mds_network_player/kernel_defconfig

Same idea for U-Boot:

make build-uboot-menuconfig
make build-uboot-savedefconfig
cp build/output/network_player/build/uboot-*/defconfig \
   mds_external/board/mds_network_player/u-boot_defconfig

(There are commented-out helper targets for this in the Makefile — feel free to revive them when stable.)