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Atmel SAMA5D3 Xplained board ============================ This document explains how to set up a basic Buildroot system on the Atmel SAMA5D3 Xplained board, whose main site is http://www.atmel.com/tools/ATSAMA5D3-XPLD.aspx. Additional details can also be found on the http://www.at91.com/linux4sam/bin/view/Linux4SAM/ web site. Note that the default Buildroot configuration is prepared to boot from an SD card: the first stage bootloader, second stage bootloader, kernel image and root filesystem are all located on the SD card. Some adjustments in the bootloader configuration will be needed to boot from NAND flash, see board/atmel/readme.txt Configuring and building Buildroot ---------------------------------- make atmel_sama5d3_xplained_mmc_defconfig make Preparing the SD card --------------------- The SD card must be partitioned with at least two partitions: one FAT16 partition for the bootloaders, kernel image and Device Tree blob, and one ext4 partition for the root filesystem. To partition the SD card: sudo sfdisk -uM /dev/mmcblk0 <<EOF ,64,6 ; EOF This creates a 64 MB partition for the FAT16 filesystem (type 6) and uses the rest for the ext4 filesystem used for the root filesystem. Then, format both partitions: sudo mkfs.msdos -n boot /dev/mmcblk0p1 sudo mkfs.ext4 -L rootfs -O ^huge_file /dev/mmcblk0p2 Note: the -O ^huge_file option is needed to avoid enabling the huge files features of ext4 (to support files larges than 2 TB), which needs the kernel option CONFIG_LBDAF to be enabled. Mount both partitions (if not done automatically by your system): sudo mount /dev/mmcblk0p1 /media/boot sudo mount /dev/mmcblk0p2 /media/rootfs Copy the bootloaders, kernel image and Device Tree blob to the first partition: cp output/images/u-boot-spl.bin /media/boot/boot.bin cp output/images/u-boot.img /media/boot/u-boot.img cp output/images/zImage /media/boot/zImage cp output/images/at91-sama5d3_xplained.dtb /media/boot/at91-sama5d3_xplained.dtb Extract the root filesystem to the second partition: sudo tar -C /media/rootfs -xf output/images/rootfs.tar Unmount both partitions: sudo umount /media/boot sudo umount /media/rootfs Insert your SD card in your Xplained board, and enjoy. The default U-Boot environment will properly load the kernel and Device Tree blob from the first partition of the SD card, so everything works automatically.