I currently got HDMI working on my big flat screen TV, 50".
It’s rather inconvenient as it is so big. So I specifically bought a small 5" display for the job.
It works on my RPi, and also my desktop computer, but linaro seems to not work on it. I also tried booting to an SD Card to reinstall Linaro, but even the installation screen does not show up on the display.
800x480 is extremely low resolution. You would probably have better luck with something higher and more standard.