While testing some virtualisation configurations I came across mention that it is possible for qemu to run code compiled for different architectures. I was particularly interested in arm, as I could then run some quick testing of Raspberry Pi stuff from my laptop.
So here is how to get Raspbian OS running under qemu.
I needed to install the package containing qemu-system-arm to allow me to run software compiled for arm. I also needed a suitable kernel compiled for arm as well, there are some good instructions located at http://xecdesign.com/compiling-a-kernel/ .
The particular arm cpu I am going to use is arm1176, first double check that this is provided by qemu, it should show up in the list of cpus given by the command
qemu-system-arm -cpu ?
The particular arm machine I am going to use is versatilepb, for a full list of machines run
qemu-system-arm -M ?
Next I need a copy of Raspbian OS image from http://www.raspberrypi.org/downloads, extract from the archive.
To boot the OS I use the following command
qemu-system-arm -kernel <location of kernel for arm> -cpu arm1176 -m 256 -M versatilepb -no-reboot -serial stdio -append "root=/dev/sda2 panic=1" -hda 2013-07-26-wheezy-raspbian.img
This did not work upon first attempt, this is mentioned on the Raspberry Pi forums. I changed my command to include an additional kernel boot parameter init=/bin/sh, and once booted up I remounted the root filesystem rw and commented out the line in /etc/ld.so.preload.
I restarted the OS using the unmodified command above and it booted.
Notes on various technologies and other cool stuff I am playing around with. My own technical stream of consciousness.
