rust-embedded / rust-embedded/cortex-m

SWI / SVC support

Open
#265 8 comments 1 reaction 0 assignees View on GitHub

Nobody has claimed this yet.

Dominant language
Rust
Stars
1k
Forks
202
Avg merge
6d 2h
Merged PRs (30d)
2

Description

Could we add intrinsics for calling Software Interrupts (the SWI or SVC instruction)? We probably also want a mechanism for marshalling some number of integer arguments into registers, and back out again on the other side of the SWI (i.e. in the kernel).

TockOS do this with llvm_asm!, as you can see at https://github.com/tock/tock/blob/198ff4173e85f6b8474893c6784d38c12ead9dbb/arch/cortex-m0/src/lib.rs#L161

Contributor guide

No contributing guide indexed for this repository

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by reading the referenced TockOS implementation in arch/cortex-m0/src/lib.rs, especially its llvm_asm! usage. Define the required SWI/SVC intrinsic behavior and argument marshalling, then verify that calls can pass integer arguments into the kernel and return them afterward.

Written by the indexing model from the issue text.

Assessment

Tech stack
rust
Domain
embedded-iot
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.