[U-Boot] U-boot for 64bit ARMv8

[Richard Schmitt]

Is anyone considering porting/supporting uboot for ARMv8.  Our initial investigation of boot loader support for ARMv8 indicates that the only boot loader currently being targeted is UEFI.  

The decisions we need to make are:
- Do we move to UEFI on ARM?
- Can we leverage someone else's enablement of ARMv8?
- Do we provide our own enablement of ARMv8?

Any opinions?

Rich