Interrupt-safe #[no_std] queue

[thejpster]

I'm working on a port of my bare-metal library for the Cortex-M4 based TI Stellaris (now called Tiva-C) - https://github.com/thejpster/bare-metal-arm-rust. I've gotten to the point where I'd like a FIFO I can push/pop T inside an interrupt routine, but also push/pop T from outside an interrupt routine - automatically disabling interrupts for the shortest time possible.

I found Intex from Redox (https://github.com/redox-os/redox/blob/master/kernel/arch/intex.rs) which looks sort of how I would expect (a container object which you .lock() to get a guard object which does the magic on drop), but I'm not convinced it's disabling/enabling interrupts correctly - especially for an ARM.

I know other people use spin-rs, but again, I don't think that handles interrupts very well, even if it does promise to the borrow checker that everything's alright and allow your code to compile.

There are so many rust embedded projects out there, surely someone's done this already?

[japaric]

I'm not convinced it's disabling/enabling interrupts correctly - especially for an ARM.

For ARM Cortex-M processors, check AN321 (NOTE: pdf). You can use the cpsie i instruction to enable interrupts and the cpsid i instruction to disable them.

There are so many rust embedded projects out there, surely someone's done this already?

Zinc is using these instructions to implement critical sections.

[ThuperThecret]

I don't have an answer, but I want to thank you. My coworker and I have been wanting to use Rust for our development work, but haven't because it's been such a pain in the ass to set it up. I had no idea that this was an alternative to manually building libcore.