Interrupt support

[xpulabs]

Hello,

I want to the hal support interrupt or not. Please give me some examples of interrrupt like gpio interrupt and so on.

Thanks

[Disasm]

Please take a look: https://github.com/riscv-rust/longan-nano/blob/master/examples/interrupt.rs

[katyo]

@Disasm Is it possible port eclic-mode-hack.S to Rust using inline asm?

[Disasm]

@katyo yes, this should be possible.