buildroot构建rootfs和app,官方源码包

Notes on using Grub2 for BIOS-based platforms ============================================= 1. Create a disk image dd if=/dev/zero of=disk.img bs=1M count=32 2. Partition it (either legacy or GPT style partitions work) cfdisk disk.img - Create one partition, type Linux, for the root filesystem. The only constraint is to make sure there is enough free space *before* the first partition to store Grub2. Leaving 1 MB of free space is safe. 3. Setup loop device and loop partitions sudo losetup -f disk.img sudo partx -a /dev/loop0 4. Prepare the root partition sudo mkfs.ext3 -L root /dev/loop0p1 sudo mount /dev/loop0p1 /mnt sudo tar -C /mnt -xf output/images/rootfs.tar sudo umount /mnt 5. Install Grub2 sudo ./output/host/sbin/grub-bios-setup \ -b ./output/host/lib/grub/i386-pc/boot.img \ -c ./output/images/grub.img -d . /dev/loop0 6. Cleanup loop device sudo partx -d /dev/loop0 sudo losetup -d /dev/loop0 7. Your disk.img is ready! Using genimage -------------- If you use genimage to generate your complete image, installing Grub can be tricky. Here is how to achieve Grub's installation with genimage: partition boot { in-partition-table = "no" image = "path_to_boot.img" offset = 0 size = 512 } partition grub { in-partition-table = "no" image = "path_to_grub.img" offset = 512 } The result is not byte to byte identical to what grub-bios-setup does but it works anyway. To test your BIOS image in Qemu ------------------------------- qemu-system-{i386,x86-64} -hda disk.img Notes on using Grub2 for x86/x86_64 EFI-based platforms ======================================================= 1. Create a disk image dd if=/dev/zero of=disk.img bs=1M count=32 2. Partition it with GPT partitions cgdisk disk.img - Create a first partition, type EF00, for the bootloader and kernel image - Create a second partition, type 8300, for the root filesystem. 3. Setup loop device and loop partitions sudo losetup -f disk.img sudo partx -a /dev/loop0 4. Prepare the boot partition sudo mkfs.vfat -n boot /dev/loop0p1 sudo mount /dev/loop0p1 /mnt sudo cp -a output/images/efi-part/* /mnt/ sudo cp output/images/bzImage /mnt/ sudo umount /mnt 5. Prepare the root partition sudo mkfs.ext3 -L root /dev/loop0p2 sudo mount /dev/loop0p2 /mnt sudo tar -C /mnt -xf output/images/rootfs.tar sudo umount /mnt 6 Cleanup loop device sudo partx -d /dev/loop0 sudo losetup -d /dev/loop0 7. Your disk.img is ready! To test your i386/x86-64 EFI image in Qemu ------------------------------------------ 1. Download the EFI BIOS for Qemu Version IA32 or X64 depending on the chosen Grub2 platform (i386-efi vs. x86-64-efi) https://www.kraxel.org/repos/jenkins/edk2/ (or use one provided by your distribution as OVMF) 2. Extract, and rename OVMF.fd to bios.bin and CirrusLogic5446.rom to vgabios-cirrus.bin. 3. qemu-system-{i386,x86-64} -L ovmf-dir/ -hda disk.img 4. Make sure to pass pci=nocrs to the kernel command line, to workaround a bug in the EFI BIOS regarding the EFI framebuffer. Notes on using Grub2 for ARM u-boot-based platforms =================================================== The following steps show how to use the Grub2 arm-uboot platform support in the simplest way possible and with a single buildroot-generated filesystem. 1. Load qemu_arm_vexpress_defconfig 2. Enable u-boot with the vexpress_ca9x4 board name and with u-boot.elf image format. 3. Enable grub2 for the arm-uboot platform. 4. Enable "Install kernel image to /boot in target" in the kernel menu to populate a /boot directory with zImage in it. 5. The upstream u-boot vexpress_ca9x4 doesn't have CONFIG_API enabled by default, which is required. Before building, patch u-boot (for example, make u-boot-extract to edit the source before building) file include/configs/vexpress_common.h to define: #define CONFIG_API #define CONFIG_SYS_MMC_MAX_DEVICE 1 6. Create a custom grub2 config file with the following contents and set its path in BR2_TARGET_GRUB2_CFG: set default="0" set timeout="5" menuentry "Buildroot" { set root='(hd0)' linux /boot/zImage root=/dev/mmcblk0 console=ttyAMA0 devicetree /boot/vexpress-v2p-ca9.dtb } 7. Create a custom builtin config file with the following contents and set its path in BR2_TARGET_GRUB2_BUILTIN_CONFIG: set root=(hd0) set prefix=/boot/grub 8. Create a custom post-build script which copies files from ${BINARIES_DIR}/boot-part to $(TARGET_DIR)/boot (set its path in BR2_ROOTFS_POST_BUILD_SCRIPT): #!/bin/sh cp -r ${BINARIES_DIR}/boot-part/* ${TARGET_DIR}/boot/ 9. make 10. Run qemu with: qemu-system-arm -M vexpress-a9 -kernel output/images/u-boot -m 1024 \ -nographic -sd output/images/rootfs.ext2 11. In u-boot, stop at the prompt and run grub2 with: => ext2load mmc 0:0 ${loadaddr} /boot/grub/grub.img => bootm 12. This should bring the grub2 menu, upon which selecting the "Buildroot" entry should boot Linux. Notes on using Grub2 for Aarch64 EFI-based platforms ==================================================== The following steps show how to use the Grub2 arm64-efi platform, using qemu and EFI firmware built for qemu. 1. Load aarch64_efi_defconfig 2. make 3. Download the EFI firmware for qemu aarch64 https://www.kraxel.org/repos/jenkins/edk2/ (or use one provided by your distribution as OVMF-aarch64 or AAVMF) 4. Run qemu with: qemu-system-aarch64 -M virt -cpu cortex-a57 -m 512 -nographic \ -bios <path/to/EDK2>/QEMU_EFI.fd -hda output/images/disk.img \ -netdev user,id=eth0 -device virtio-net-device,netdev=eth0 5. This should bring the grub2 menu, upon which selecting the "Buildroot" entry should boot Linux.