Raspberry Pi Intro ===== These instructions apply to all models of the Raspberry Pi: - the original models A and B, - the "enhanced" models A+ and B+, - the model B2 (aka Raspberry Pi 2) - the model B3 (aka Raspberry Pi 3). - the model B4 (aka Raspberry Pi 4). How to build it =============== Configure Buildroot ------------------- There are two RaspberryPi defconfig files in Buildroot, one for each major variant, which you should base your work on: For models A, B, A+ or B+: $ make raspberrypi_defconfig For model Zero (model A+ in smaller form factor): $ make raspberrypi0_defconfig For model 2 B: $ make raspberrypi2_defconfig For model 3 B and B+: $ make raspberrypi3_defconfig For model 4 B: $ make raspberrypi4_defconfig Build the rootfs ---------------- Note: you will need to have access to the network, since Buildroot will download the packages' sources. You may now build your rootfs with: $ make (This may take a while, consider getting yourself a coffee ;-) ) Result of the build ------------------- After building, you should obtain this tree: output/images/ +-- bcm2708-rpi-b.dtb [1] +-- bcm2708-rpi-b-plus.dtb [1] +-- bcm2709-rpi-2-b.dtb [1] +-- bcm2710-rpi-3-b.dtb [1] +-- bcm2710-rpi-3-b-plus.dtb [1] +-- bcm2711-rpi-4-b.dtb [1] +-- boot.vfat +-- rootfs.ext4 +-- rpi-firmware/ | +-- bootcode.bin | +-- cmdline.txt | +-- config.txt | +-- fixup.dat | +-- start.elf | `-- overlays/ [2] +-- sdcard.img `-- zImage [1] Not all of them will be present, depending on the RaspberryPi model you are using. [2] Only for the Raspberry Pi 3/4 Models (overlay pi3-miniuart-bt is needed to enable the RPi3 serial console otherwise occupied by the bluetooth chip). Alternative would be to disable the serial console in cmdline.txt and /etc/inittab. How to write the SD card ======================== Once the build process is finished you will have an image called "sdcard.img" in the output/images/ directory. Copy the bootable "sdcard.img" onto an SD card with "dd": $ sudo dd if=output/images/sdcard.img of=/dev/sdX Insert the SDcard into your Raspberry Pi, and power it up. Your new system should come up now and start two consoles: one on the serial port on the P1 header, one on the HDMI output where you can login using a USB keyboard.