sudo apt-get install qemu
Download vmlinuz and initrd from Wheezy netboot. Note that you need 'armel' for ARM v5, v6 and 'armhf' for ARM v7. Cortex-A8, A9, A15 are all ARMv7 CPUs.
Create a hard disk for your virtual machine
qemu-img create -f raw armdisk-cortex-a9.img 8G
Start a virtual machine with 1024 MB RAM and a Cortex-A9 CPU.
qemu-system-arm -m 1024M -cpu cortex-a9 -M versatilepb -kernel vmlinuz-3.2.0-4-versatile -initrd initrd.gz -hda armdisk-cortex-a9.img -append "root=/dev/ram"