Compile Linux firmware Download the SDK Please contact sales@t-firefly.com to get SDK download link and read the readme file Notice: 1. SDK use cross-compilation, so use SDK in x86_64 PC, do not download SDK to the device 2. We suggest to use Ubuntu20.04 (real PC or docker) to build, other OS may cause building failure 3. Do not place or decompress the SDK archive in Virtual Machine share folder or non-english folder 4. Please use the regular user to get/compile the SDK, use root privilege may cause building failure SDK Introduction SDK Structure $ tree -L 1 . ├── app ├── buildroot # buildroot ├── build.sh -> device/rockchip/common/scripts/build.sh # building script ├── device # building system, includes building configs ├── docs # development documents ├── external # some components ├── kernel # linux kernel ├── Makefile -> device/rockchip/common/Makefile ├── prebuilt_rootfs # used to place pre-built rootfs ├── prebuilts # used to place cross-build toolchain ├── rkbin ├── rkflash.sh -> device/rockchip/common/scripts/rkflash.sh ├── tools # some tools └── u-boot # uboot About Configurations There are many config files (xxxx_defconfig) under "device/rockchip/rk3576/", these files control the building system. And their names will be like: __-__defconfig vendor: vendor of the product chip: soc the product used model: product model, means this config file is for that specific product. extra: some extra features, could be empty OS: the operating system that will be running in product About config file contents, take firefly_rk3576_aio- 3576jd4_debian_defconfig as an example: #include "firefly.config" # includes firefly.config PREBUILT_ROOTFS_IMG="prebuilt_rootfs/rk3576_debian_rootfs.img" # set the prebuilt rootfs to be used RK_PARAMETER="parameter-ubuntu-fit.txt" # set the partition parameter RK_KERNEL_DTS_NAME="rk3576-firefly-aio-3576jd4" # set the dts to be used during kernel compilation RK_PRODUCT_MODEL="AIO-3576JD4" # product name/model UBOOT_DEBUG_BAUDRATE="115200" # set debug serial baudrate as 115200 And firefly.config mainly has: RK_KERNEL_CFG_FRAGMENTS="firefly-linux.config firefly-docker.config" # set the config fragments to be used during kernel compilation RK_UBOOT_CFG_FRAGMENTS="firefly-linux" # set the config fragments to be used during uboot compilation USE_EXTBOOT=y # use exlinux style boot.img Partitions Parameter file records the firmware partitions, for example "device/rockchip/rk3576/parameter-xxxxxx-fit.txt" FIRMWARE_VER: 1.0 MACHINE_MODEL: RK357 MACHINE_ID: 007 MANUFACTURER: RK3576 MAGIC: 0x5041524B ATAG: 0x00200800 MACHINE: 0xffffffff CHECK_MASK: 0x80 PWR_HLD: 0,0,A,0,1 TYPE: GPT GROW_ALIGN: 0 CMDLINE: mtdparts=:0x00004000@0x00004000(uboot),0x00002000@0x00008000(misc),0x00040000@0x0000a000(boot:bootable),0x00040000@0x0004a000(recovery),0x00010000@0x0008a000(backup),0x00c00000@0x0009a000(rootfs),-@0x00c9a000(userdata:grow) uuid:rootfs=614e0000-0000-4b53-8000-1d28000054a9 uuid:boot=7A3F0000-0000-446A-8000-702F000062736 CMDLINE is what we need to focus on, in "0x00040000@0x0000a000(boot:bootable)", 0x0000a000 is the start position of boot, and 0x00040000 is the size of boot partition. Start position + Partition size = Start position of the next partition. All partitions follow the same rule. And the unit of these hex numbers is "block", each block is 512 Byte, which means boot partition size 0x00040000 is 262144 block = 262144 x 512 / 1024 / 1024 = 128 MiB Build Ubuntu Firmware Preparations Run these two commands to install necessary tools sudo apt update sudo apt install repo git ssh make gcc libssl-dev liblz4-tool \ expect g++ patchelf chrpath gawk texinfo chrpath diffstat binfmt-support \ qemu-user-static live-build bison flex fakeroot cmake gcc-multilib g++-multilib \ unzip device-tree-compiler ncurses-dev p7zip-full Download rootfs here Ubuntu rootfs , in general, choose the filesystem with latest date. After download, decompress and move the rootfs image to SDK/prebuilt_rootfs/, then create a symbolic link. # Decompress 7z x Ubuntu22.04-xxxx.7z mv Ubuntu22.04-xxxx.img ./rk3576_sdk/prebuilt_rootfs/ cd ./rk3576_sdk/prebuilt_rootfs/ ln -sf Ubuntu22.04-xxxx.img rk3576_ubuntu_rootfs.img cd .. Configurations Run "./build.sh lunch" to list all available configs, enter a number to select. Please choose one with "ubuntu" keyword: ./build.sh lunch ############### Rockchip Linux SDK ############### Manifest: rk3576_linux_release_20250520_v1.0.1f.xml Log colors: message notice warning error fatal Log saved at /home2/liuth/project/linux/rk3576/output/sessions/2025-08-06_15-27-20 Pick a defconfig: 1. rockchip_defconfig 2. firefly_rk3576_aio-3576c_buildroot_defconfig 3. firefly_rk3576_aio-3576c_debian_defconfig 4. firefly_rk3576_aio-3576c_ubuntu_defconfig 5. firefly_rk3576_aio-3576jd4_buildroot_defconfig 6. firefly_rk3576_aio-3576jd4_debian_defconfig 7. firefly_rk3576_aio-3576jd4_ubuntu_defconfig ...... ...... 24. firefly_rk3576_roc-rk3576-pc_buildroot_defconfig 25. firefly_rk3576_roc-rk3576-pc_debian_defconfig 26. firefly_rk3576_roc-rk3576-pc_ubuntu_defconfig 27. rockchip_rk3576_evb1_v10_defconfig 28. rockchip_rk3576_industry_evb_v10_defconfig 29. rockchip_rk3576_iotest_v10_defconfig 30. rockchip_rk3576_ipc_evb1_v10_defconfig 31. rockchip_rk3576_multi_ipc_evb1_v10_defconfig 32. rockchip_rk3576_test1_v10_defconfig 33. rockchip_rk3576_test2_v10_defconfig 34. rockchip_rk3576_vehicle_evb_v10_defconfig 35. rockchip_rk3576_vehicle_evb_v20_mos_defconfig Which would you like? [1]: Compilation Full Compilation Run ./build.sh all The output firmware will be "output/update/update.img" Partial Compilation After a full compilation, if you modified kernel or uboot, you can do partial compilation to save time. Only build u-boot, will generate u-boot/uboot.img ./build.sh uboot Only build kernel, will generate kernel/extboot.img ./build.sh extboot Pack all parts to update.img ./build.sh updateimg