Booting a QEMU based BeagleBoard

• Linaro has contributed a significant amount of effort to improving and maintaining the beagleboard port in QEMU. Here are the instructions for creating a bootable image and then using this image to boot to a shell prompt on your host.

Download and install required packages

• You can download a pre-built image

• Or build your own with some customizations:
  • Download linaro-media-create

    • $ apt-get install linaro-image-tools 

  • Download a rootfs and a hwpack
    • Six-monthly Linaro releases can be found at:

      • http://releases.linaro.org/

    • The daily releases (which may or may not work) can be found at:

      • http://snapshots.linaro.org/

• Install QEMU

  • $ apt-get install qemu-user-static qemu-system

Building a runnable image

• Use linaro-media-create to build an image you can use to boot
• The resulting image will be owned by root; make it owned by you so you can run QEMU as your normal user:
• sudo chown your-username:your-username beagle.img

Run the image in QEMU

$ qemu-system-arm -M beaglexm -drive if=sd,cache=writeback,file=./beagle.img -clock unix -serial stdio -device usb-kbd -device usb-mouse -usb -device usb-net,netdev=mynet -netdev user,id=mynet

USB keyboard and mouse are supported starting with qemu-linaro 2011.06, for Linaro images of the 11.05 release or later. USB networking is supported starting with qemu-linaro 2011.10.

Note the use of "cache=writeback" here: this significantly improves I/O performance over the default (cache=writethrough, or if using the old-style "-sd file.img" option). However you should be aware that if the host crashes then the guest's filesystem on the disk image may be corrupted. (Guest crashes are not problematic.) For most uses of ARM guests this is acceptable.

Updating image contents

For QEMU versions after qemu-linaro 2011.10 this section can be ignored -- just use the networking to transfer files into the guest.

For QEMU versions before qemu-linaro 2011.10, networking is unsupported, and so any files you need to transfer have to be copied to the mounted image, like this:

• We need to mount the partition in the QEMU image on the host using a loopback mount. First find the ext3 partition inside the image file by:

$ fdisk -ul beagle_sd.img
        Device Boot      Start         End      Blocks   Id  System
beagle_sd.img1   *          63      106494       53216    c  W95 FAT32 (LBA)
beagle_sd.img2          106496     4194303     2043904   83  Linux

take the "start" number of beagle_sd.img2 (106496) and feed it to the mount command multiplied by block size (512):

$ sudo mount -o loop,offset=$[106496*512] beagle_sd.img /mnt/
$ cp linux-image*_armel.deb /mnt/root/

CategoryHowTo