diff options
Diffstat (limited to 'src/lib.rs')
| -rw-r--r-- | src/lib.rs | 58 |
1 files changed, 18 insertions, 40 deletions
@@ -9,20 +9,15 @@ //! //! # Optional features //! -//! ## `inline-asm` +//! ## `critical-section-single-core` //! -//! When this feature is enabled the implementation of all the functions inside the `asm` and -//! `register` modules use inline assembly (`asm!`) instead of external assembly (FFI into separate -//! assembly files pre-compiled using `arm-none-eabi-gcc`). The advantages of enabling `inline-asm` -//! are: +//! This feature enables a [`critical-section`](https://github.com/rust-embedded/critical-section) +//! implementation suitable for single-core targets, based on disabling interrupts globally. //! -//! - Reduced overhead. FFI eliminates the possibility of inlining so all operations include a -//! function call overhead when `inline-asm` is not enabled. -//! -//! - Some of the `register` API only becomes available only when `inline-asm` is enabled. Check the -//! API docs for details. -//! -//! The disadvantage is that `inline-asm` requires a nightly toolchain. +//! It is **unsound** to enable it on multi-core targets or for code running in unprivileged mode, +//! and may cause functional problems in systems where some interrupts must be not be disabled +//! or critical sections are managed as part of an RTOS. In these cases, you should use +//! a target-specific implementation instead, typically provided by a HAL or RTOS crate. //! //! ## `cm7-r0p1` //! @@ -30,32 +25,11 @@ //! functions in this crate only work correctly on those chips if this Cargo feature is enabled //! (the functions are documented accordingly). //! -//! ## `linker-plugin-lto` -//! -//! This feature links against prebuilt assembly blobs that are compatible with [Linker-Plugin LTO]. -//! This allows inlining assembly routines into the caller, even without the `inline-asm` feature, -//! and works on stable Rust (but note the drawbacks below!). -//! -//! If you want to use this feature, you need to be aware of a few things: -//! -//! - You need to make sure that `-Clinker-plugin-lto` is passed to rustc. Please refer to the -//! [Linker-Plugin LTO] documentation for details. -//! -//! - You have to use a Rust version whose LLVM version is compatible with the toolchain in -//! `asm-toolchain`. -//! -//! - Due to a [Rust bug][rust-lang/rust#75940] in compiler versions **before 1.49**, this option -//! does not work with optimization levels `s` and `z`. -//! -//! [Linker-Plugin LTO]: https://doc.rust-lang.org/stable/rustc/linker-plugin-lto.html -//! [rust-lang/rust#75940]: https://github.com/rust-lang/rust/issues/75940 -//! //! # Minimum Supported Rust Version (MSRV) //! -//! This crate is guaranteed to compile on stable Rust 1.42 and up. It *might* +//! This crate is guaranteed to compile on stable Rust 1.59 and up. It *might* //! compile with older versions but that may change in any new patch release. -#![cfg_attr(feature = "inline-asm", feature(asm))] #![deny(missing_docs)] #![no_std] #![allow(clippy::identity_op)] @@ -79,11 +53,6 @@ // Don't warn about feature(asm) being stable on Rust >= 1.59.0 #![allow(stable_features)] -extern crate bare_metal; -extern crate volatile_register; - -#[macro_use] -mod call_asm; #[macro_use] mod macros; @@ -95,7 +64,16 @@ pub mod interrupt; #[cfg(all(not(armv6m), not(armv8m_base)))] pub mod itm; pub mod peripheral; -pub mod prelude; pub mod register; pub use crate::peripheral::Peripherals; + +#[cfg(all(cortex_m, feature = "critical-section-single-core"))] +mod critical_section; + +/// Used to reexport items for use in macros. Do not use directly. +/// Not covered by semver guarantees. +#[doc(hidden)] +pub mod _export { + pub use critical_section; +} |