[U-Boot] Full Arm emulator to run under x86

Hi

I am new to uboot and I would like to learn it under an emulator instead of a remote target. For instance, I'd like to experiment it with the Android operating system. So far, I have tried qemu (utility qemu-system-arm) to boot the kernel or an arm+uboot bootable sd flash image on x86 architecture and the result was unsuccessful. My purpose is not to run for example Android on an x86 architecture, because i know that there's Android for i386. However, more of a full Arm system emulator that should be able to boot U-boot bootloader and then the Linux kernel, and also a bootable block device or image.

thank you,

-toan