[Discussion] Integrating port specific syscall proxies

[g2gps]

With the risc-v/litex port, we're able to access the TIME and TIMEH CSRs in usermode. I would like take advantage of this feature to replace the proxies for syscalls, such as timer_gettime, with an equivalent implementation that avoids a context switch, where appropriate.

I understand that the syscall.csv database is used to generate the syscall proxies and stubs, but there doesn't seem to be any facility to provide a different implementation. Potentially, I could remove the desired syscalls from syscall.csv and provide my own proxy which is linked into libproxies, but it would be nice if this was more generally supported, rather than patching the kernel locally.

I'd be interested to know if anyone has had a similar idea, or potentially there is a method to achieve this in NuttX which I have overlooked.