currently only tested under qemu

qemu-system-arm -M highbank -nographic -m 4089 -kernel build/highbank/arch/arm/pbl/zbarebox -tftp "." -drive id=disk,if=ide,file=disk.img -device ide-drive,drive=disk,bus=ide.0

with:
 - timer (AMBA SP804)
 - uart (AMBA PL011)
 - gpio (AMBA PL061)
 - ahci
 - net (XGMAC)

Cc: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>