diff --git a/Cargo.toml b/Cargo.toml
index 392538b452695726a5d60e1e9a7112641e79077f..8ce7bdb23d1c88c8122418cea38ed3f86c3f4357 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -15,6 +15,7 @@ version = "0.2.0"
[dependencies]
cortex-m = "0.3.1"
static-ref = "0.2.1"
+rtfm-core = { git = "https://github.com/japaric/rtfm-core" }
[dependencies.cortex-m-rtfm-macros]
path = "macros"
diff --git a/macros/src/trans.rs b/macros/src/trans.rs
index a137e0ec7cb5eedf141d4af24ab12f9d5405f08f..4f389d3028e9fe9c3eaf1e25aa872ee04fa607fb 100644
--- a/macros/src/trans.rs
+++ b/macros/src/trans.rs
@@ -238,7 +238,7 @@ fn init(app: &App, main: &mut Vec<Tokens>, root: &mut Vec<Tokens>) {
// Interrupt. These can be enabled / disabled through the NVIC
if interrupts.is_empty() {
interrupts.push(quote! {
- let nvic = #device::NVIC.borrow(_cs);
+ let nvic = &*#device::NVIC.get();
});
}
@@ -262,7 +262,7 @@ fn init(app: &App, main: &mut Vec<Tokens>, root: &mut Vec<Tokens>) {
// Exception
if exceptions.is_empty() {
exceptions.push(quote! {
- let scb = #device::SCB.borrow(_cs);
+ let scb = &*#device::SCB.get();
});
}
@@ -280,7 +280,7 @@ fn init(app: &App, main: &mut Vec<Tokens>, root: &mut Vec<Tokens>) {
// type check
let init: fn(#(#tys,)*) = #init;
- #krate::atomic(|_cs| unsafe {
+ #krate::atomic(unsafe { &mut #krate::Threshold::new(0) }, |_t| unsafe {
init(#(#exprs,)*);
#(#exceptions)*
@@ -328,15 +328,19 @@ fn resources(app: &App, ownerships: &Ownerships, root: &mut Vec<Tokens>) {
fn borrow<'cs>(
&'cs self,
- _cs: &'cs #krate::CriticalSection,
+ t: &'cs #krate::Threshold,
) -> &'cs #krate::Static<#ty> {
+ assert!(t.value() >= #ceiling);
+
unsafe { #krate::Static::ref_(&#_name) }
}
fn borrow_mut<'cs>(
&'cs mut self,
- _cs: &'cs #krate::CriticalSection,
+ t: &'cs #krate::Threshold,
) -> &'cs mut #krate::Static<#ty> {
+ assert!(t.value() >= #ceiling);
+
unsafe {
#krate::Static::ref_mut(&mut #_name)
}
@@ -390,8 +394,10 @@ fn resources(app: &App, ownerships: &Ownerships, root: &mut Vec<Tokens>) {
fn borrow<'cs>(
&'cs self,
- _cs: &'cs #krate::CriticalSection,
+ t: &'cs #krate::Threshold,
) -> &'cs #krate::Static<#device::#name> {
+ assert!(t.value() >= #ceiling);
+
unsafe {
#krate::Static::ref_(&*#device::#name.get())
}
@@ -399,8 +405,10 @@ fn resources(app: &App, ownerships: &Ownerships, root: &mut Vec<Tokens>) {
fn borrow_mut<'cs>(
&'cs mut self,
- _cs: &'cs #krate::CriticalSection,
+ t: &'cs #krate::Threshold,
) -> &'cs mut #krate::Static<#device::#name> {
+ assert!(t.value() >= #ceiling);
+
unsafe {
#krate::Static::ref_mut(
&mut *#device::#name.get(),
@@ -458,7 +466,7 @@ fn resources(app: &App, ownerships: &Ownerships, root: &mut Vec<Tokens>) {
impls.push(quote! {
#[allow(unsafe_code)]
- impl #krate::Resource for _resource::#name {
+ unsafe impl #krate::Resource for _resource::#name {
#(#impl_items)*
}
});
@@ -594,7 +602,13 @@ fn tasks(app: &App, ownerships: &Ownerships, root: &mut Vec<Tokens>) {
let priority = task.priority;
if needs_threshold {
tys.push(quote!(&mut #krate::Threshold));
- exprs.push(quote!(&mut #krate::Threshold::new(#priority)));
+ exprs.push(quote! {
+ &mut if #priority == 1 << #device::NVIC_PRIO_BITS {
+ #krate::Threshold::new(::core::u8::MAX)
+ } else {
+ #krate::Threshold::new(#priority)
+ }
+ });
}
if has_resources {
diff --git a/src/lib.rs b/src/lib.rs
index 43079c17575a89f3361ddf28cfab045ad6218fc0..ba9676234182886b712231f6d90eadc9b7b4040e 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -50,7 +50,6 @@
//!
//! In increasing grade of complexity, see the [examples](./examples/index.html)
//! module.
-
#![deny(missing_docs)]
#![deny(warnings)]
#![feature(asm)]
@@ -61,76 +60,32 @@
extern crate cortex_m;
extern crate cortex_m_rtfm_macros;
+extern crate rtfm_core;
extern crate static_ref;
+use core::u8;
+
+pub use rtfm_core::{Resource, Static, Threshold};
pub use cortex_m::asm::{bkpt, wfi};
-pub use cortex_m::interrupt::CriticalSection;
-pub use cortex_m::interrupt::free as atomic;
pub use cortex_m_rtfm_macros::app;
-pub use static_ref::Static;
-use cortex_m::interrupt::Nr;
+use cortex_m::interrupt::{self, Nr};
#[cfg(not(armv6m))]
-use cortex_m::register::{basepri, basepri_max};
+use cortex_m::register::basepri;
pub mod examples;
-/// A resource, a means to share data between tasks
-pub trait Resource {
- /// The data protected by the resource
- type Data;
-
- /// Borrows the resource data for the duration of a *global* critical
- /// section
- fn borrow<'cs>(
- &'cs self,
- cs: &'cs CriticalSection,
- ) -> &'cs Static<Self::Data>;
-
- /// Mutable variant of `borrow`
- fn borrow_mut<'cs>(
- &'cs mut self,
- cs: &'cs CriticalSection,
- ) -> &'cs mut Static<Self::Data>;
-
- /// Claims the resource data for the span of the closure `f`. For the
- /// duration of the closure other tasks that may access the resource data
- /// are prevented from preempting the current task.
- fn claim<R, F>(&self, t: &mut Threshold, f: F) -> R
- where
- F: FnOnce(&Static<Self::Data>, &mut Threshold) -> R;
-
- /// Mutable variant of `claim`
- fn claim_mut<R, F>(&mut self, t: &mut Threshold, f: F) -> R
- where
- F: FnOnce(&mut Static<Self::Data>, &mut Threshold) -> R;
-}
-
-impl<T> Resource for Static<T> {
- type Data = T;
-
- fn borrow<'cs>(&'cs self, _cs: &'cs CriticalSection) -> &'cs Static<T> {
- self
- }
-
- fn borrow_mut<'cs>(
- &'cs mut self,
- _cs: &'cs CriticalSection,
- ) -> &'cs mut Static<T> {
- self
- }
-
- fn claim<R, F>(&self, t: &mut Threshold, f: F) -> R
- where
- F: FnOnce(&Static<Self::Data>, &mut Threshold) -> R,
- {
- f(self, t)
- }
-
- fn claim_mut<R, F>(&mut self, t: &mut Threshold, f: F) -> R
- where
- F: FnOnce(&mut Static<Self::Data>, &mut Threshold) -> R,
- {
- f(self, t)
+/// Executes the closure `f` in an interrupt free context
+pub fn atomic<R, F>(t: &mut Threshold, f: F) -> R
+where
+ F: FnOnce(&mut Threshold) -> R,
+{
+ if t.value() == u8::MAX {
+ f(t)
+ } else {
+ interrupt::disable();
+ let r = f(&mut unsafe { Threshold::max() });
+ unsafe { interrupt::enable() };
+ r
}
}
@@ -147,20 +102,19 @@ where
F: FnOnce(T, &mut Threshold) -> R,
{
let max_priority = 1 << nvic_prio_bits;
- if ceiling > t.value {
+ if ceiling > t.value() {
match () {
#[cfg(armv6m)]
- () => {
- atomic(|_| f(data, &mut Threshold::new(max_priority)))
- }
+ () => atomic(t, |t| f(data, t)),
+
#[cfg(not(armv6m))]
() => {
if ceiling == max_priority {
- atomic(|_| f(data, &mut Threshold::new(max_priority)))
+ atomic(t, |t| f(data, t))
} else {
let old = basepri::read();
let hw = (max_priority - ceiling) << (8 - nvic_prio_bits);
- basepri_max::write(hw);
+ basepri::write(hw);
let ret = f(data, &mut Threshold::new(ceiling));
basepri::write(old);
ret
@@ -172,25 +126,6 @@ where
}
}
-/// Preemption threshold token
-///
-/// The preemption threshold indicates the priority a task must have to preempt
-/// the current context. For example a threshold of 2 indicates that only
-/// interrupts / exceptions with a priority of 3 or greater can preempt the
-/// current context
-pub struct Threshold {
- value: u8,
-}
-
-impl Threshold {
- #[doc(hidden)]
- pub unsafe fn new(value: u8) -> Self {
- Threshold { value }
- }
-}
-
-impl !Send for Threshold {}
-
/// Sets an interrupt as pending
///
/// If the interrupt priority is high enough the interrupt will be serviced
@@ -205,63 +140,6 @@ where
nvic.set_pending(interrupt);
}
-/// Binds a task `$handler` to the interrupt / exception `$NAME`
-///
-/// This macro takes two arguments: the name of an exception / interrupt and the
-/// path to the function that will be used as the task handler. That function
-/// must have signature `fn(&mut Threshold, $NAME::Resources)`.
-///
-/// Optionally, a third argument may be used to declare task local data.
-/// The handler will have exclusive access to these *local* variables on each
-/// invocation. If the third argument is used then the signature of the handler
-/// function must be `fn(&mut Threshold, &mut $locals, $NAME::Resources)`.
-#[macro_export]
-macro_rules! task {
- ($NAME:ident, $handler:path) => {
- #[allow(non_snake_case)]
- #[allow(unsafe_code)]
- #[no_mangle]
- pub unsafe extern "C" fn $NAME() {
- let f: fn(&mut $crate::Threshold, ::$NAME::Resources) = $handler;
-
- f(
- &mut $crate::Threshold::new(::$NAME::$NAME),
- ::$NAME::Resources::new(),
- );
- }
- };
-
- ($NAME:ident, $handler:path, $locals:ident {
- $(static $var:ident: $ty:ty = $expr:expr;)+
- }) => {
- #[allow(non_snake_case)]
- struct $locals {
- $($var: $crate::Static<$ty>,)+
- }
-
- #[allow(non_snake_case)]
- #[allow(unsafe_code)]
- #[no_mangle]
- pub unsafe extern "C" fn $NAME() {
- let f: fn(
- &mut $crate::Threshold,
- &mut $locals,
- ::$NAME::Resources,
- ) = $handler;
-
- static mut LOCALS: $locals = $locals {
- $($var: unsafe { $crate::Static::new($expr) },)+
- };
-
- f(
- &mut $crate::Threshold::new(::$NAME::$NAME),
- &mut LOCALS,
- ::$NAME::Resources::new(),
- );
- }
- };
-}
-
#[allow(non_camel_case_types)]
#[doc(hidden)]
pub enum Exception {