I am planning to support ARMv8-A/R for Nuttx, the features are:

1. ARMv8 architecture core (cotex-a53/cotex-a72/cotex-r82) support
2. SMP support
3. FPU context switch suppot
4. BUILD_PROTECTED and BUILD_KERNEL config support
5. board support: imx8qm-mek, qemu(aarch64) and fvp-aemv8r

At present, I complete a init version with follow features:

1. cotex-a53 single core support
2. FPU context switch suppot
3. support nsh shell and ostest is passed
4. support imx8qm-mek board

I will upload code for evaluate when the internal code review is complete
and continue to work at the unfinished features