README.md

QEMU ARM Machine Project

This project contains a script and example files to set up and boot an ARM machine using QEMU. It includes a bash script to manage the virtual machine, create an SD card image, and provide necessary example files.

• QEMU ARM Machine Project
  • Contents
  • Prerequisites
  • Tutorials I Followed
  • Usage
    • Generating SD Card Image
    • Mounting the SD Card Image
    • Unmounting the SD Card Image
    • Booting the QEMU Machine
  • Example Files
  • Versions
  • License

Contents

• machine: Bash script to manage the QEMU ARM machine.
• examples/: Directory containing example files for the boot and root filesystem.

Prerequisites

• QEMU

• Parted

• Loopback device setup utilities (usually part of util-linux)

Tutorials I Followed

• Qemu (Raspberrypi at Home) Embedded Linux Playlist by Moatasem Elsayed

• bootlin's Embedded Linux System Development - QEMU ARM variant - Practical Labs

Usage

The script will prompt for sudo when necessary.

Generating SD Card Image

To create a new SD card image:

./machine generate

This will create an empty 1GB image sdcard.img, partition it, format the partitions and copy the example files to the appropriate partitions.

Partitions:

Name	Size	Type	MountPoint
Boot	10MiB	FAT16	/boot
RootFS	The rest	ext4	/

After generating the image, you need to:

• Add the uboot file to the same working directory (./uboot).

• Copy the zImage file to mnt/root/:

# The path could be different in your case
sudo cp -f zImage mnt/root/

• Copy the crosstool-ng sysroot dir to mnt/rootfs/:

# The path could be different in your case
sudo cp -rf ~/x-tools/arm-linux-gnueabihf/arm-linux-gnueabihf/sysroot/* mnt/rootfs/

• Copy the busybox output to mnt/rootfs/ too:

# The path could be different in your case
sudo cp -rf busybox/_install/* mnt/rootfs/

Don't forget to unmount the mnt:

./machine umount

Mounting the SD Card Imager

To mount the SD card image:

./machine mount

This will mount the boot and root filesystem partitions at ./mnt/boot and mnt/rootfs respectively.

Unmounting the SD Card Image

To unmount the SD card image:

./machine umount

This will unmount the boot and root filesystem partitions and detach the loop device.

Booting the QEMU Machine

To boot the QEMU machine:

./machine boot

This will start the QEMU ARM machine with the SD card image.

Example Files

Path examples/: Directory containing example files for the boot and root filesystem.

• examples/boot/uboot.env: U-Boot environment file.

  The following environment variables are set:

  • bootargs: console=ttyAMA0,115200 root=/dev/mmcblk0p2 rootfstype=ext4 rw

  • bootcmd: fatload mmc 0:1 $kernel_addr_r zImage; fatload mmc 0:1 $fdt_addr_r vexpress-v2p-ca9.dtb; bootz $kernel_addr_r - $fdt_addr_r

• examples/boot/vexpress-v2p-ca9.dtb: Device Tree file of the vexpress-cortext9.

• examples/rootfs/etc/: Some configuration files and init scripts including: passwd, shadow, group, fstab, inittab, issue, hostname

Versions

• zImage and vexpress-v2p-ca9.dtb: Linux Kernel 6.7.y

• Crosstool-ng: 1.26.0

• Busybox: 1.36.1

• U-Boot: 2023.01

License

This project is licensed under the MIT License.