pub interface to logical2hw and hw2logical

This commit is contained in:
pln 2017-04-17 18:40:56 +02:00
parent a94de6bafc
commit dad3a1f520

View file

@ -47,8 +47,7 @@ pub struct Resource<T, CEILING> {
impl<T, C> Resource<T, C> {
/// Creates a new resource with ceiling `C`
pub const fn new(data: T) -> Self
where
C: Ceiling,
where C: Ceiling
{
Resource {
_ceiling: PhantomData,
@ -62,14 +61,12 @@ impl<T, CEILING> Resource<T, C<CEILING>> {
/// section
///
/// This operation is zero cost and doesn't impose any additional blocking
pub fn borrow<'cs, PRIORITY, SCEILING>(
&'static self,
_priority: &P<PRIORITY>,
_system_ceiling: &'cs C<SCEILING>,
) -> Ref<'cs, T>
where
SCEILING: GreaterThanOrEqual<CEILING>,
CEILING: GreaterThanOrEqual<PRIORITY>,
pub fn borrow<'cs, PRIORITY, SCEILING>(&'static self,
_priority: &P<PRIORITY>,
_system_ceiling: &'cs C<SCEILING>)
-> Ref<'cs, T>
where SCEILING: GreaterThanOrEqual<CEILING>,
CEILING: GreaterThanOrEqual<PRIORITY>
{
unsafe { Ref::new(&*self.data.get()) }
}
@ -77,24 +74,18 @@ impl<T, CEILING> Resource<T, C<CEILING>> {
/// Claims the resource at the task with highest priority
///
/// This operation is zero cost and doesn't impose any additional blocking
pub fn claim<'task, PRIORITY>(
&'static self,
_priority: &'task P<PRIORITY>,
) -> Ref<'task, T>
where
CEILING: Cmp<PRIORITY, Output = Equal>,
pub fn claim<'task, PRIORITY>(&'static self, _priority: &'task P<PRIORITY>) -> Ref<'task, T>
where CEILING: Cmp<PRIORITY, Output = Equal>
{
unsafe { Ref::new(&*self.data.get()) }
}
/// Like [Resource.claim](struct.Resource.html#method.claim) but returns a
/// `&mut-` reference
pub fn claim_mut<'task, PRIORITY>(
&'static self,
_priority: &'task mut P<PRIORITY>,
) -> RefMut<'task, T>
where
CEILING: Cmp<PRIORITY, Output = Equal>,
pub fn claim_mut<'task, PRIORITY>(&'static self,
_priority: &'task mut P<PRIORITY>)
-> RefMut<'task, T>
where CEILING: Cmp<PRIORITY, Output = Equal>
{
unsafe { RefMut::new(&mut *self.data.get()) }
}
@ -109,22 +100,15 @@ impl<T, CEILING> Resource<T, C<CEILING>> {
/// than `CEILING` can be borrowed at zero cost. See
/// [Resource.borrow](struct.Resource.html#method.borrow).
#[cfg(not(thumbv6m))]
pub fn lock<R, PRIORITY, F>(
&'static self,
_priority: &P<PRIORITY>,
f: F,
) -> R
where
F: FnOnce(Ref<T>, C<CEILING>) -> R,
CEILING: Cmp<PRIORITY, Output = Greater> + Cmp<UMAX, Output = Less>
+ Level,
pub fn lock<R, PRIORITY, F>(&'static self, _priority: &P<PRIORITY>, f: F) -> R
where F: FnOnce(Ref<T>, C<CEILING>) -> R,
CEILING: Cmp<PRIORITY, Output = Greater> + Cmp<UMAX, Output = Less> + Level
{
unsafe {
let old_basepri = basepri::read();
basepri_max::write(<CEILING>::hw());
barrier!();
let ret =
f(Ref::new(&*self.data.get()), C { _marker: PhantomData });
let ret = f(Ref::new(&*self.data.get()), C { _marker: PhantomData });
barrier!();
basepri::write(old_basepri);
ret
@ -138,15 +122,9 @@ impl<T, CEILING> Resource<T, C<CEILING>> {
/// resource that has ceiling equal `CEILING`. This constraint is required
/// to preserve Rust aliasing rules.
#[cfg(not(thumbv6m))]
pub fn lock_mut<R, PRIORITY, F>(
&'static self,
_priority: &mut P<PRIORITY>,
f: F,
) -> R
where
F: FnOnce(RefMut<T>) -> R,
CEILING: Cmp<PRIORITY, Output = Greater> + Cmp<UMAX, Output = Less>
+ Level,
pub fn lock_mut<R, PRIORITY, F>(&'static self, _priority: &mut P<PRIORITY>, f: F) -> R
where F: FnOnce(RefMut<T>) -> R,
CEILING: Cmp<PRIORITY, Output = Greater> + Cmp<UMAX, Output = Less> + Level
{
unsafe {
let old_basepri = basepri::read();
@ -160,32 +138,25 @@ impl<T, CEILING> Resource<T, C<CEILING>> {
}
}
unsafe impl<T, C> Sync for Resource<T, C>
where
C: Ceiling,
{
}
unsafe impl<T, C> Sync for Resource<T, C> where C: Ceiling {}
/// A hardware peripheral as a resource
pub struct Peripheral<P, CEILING>
where
P: 'static,
where P: 'static
{
peripheral: cortex_m::peripheral::Peripheral<P>,
_ceiling: PhantomData<CEILING>,
}
impl<P, C> Peripheral<P, C>
where
C: Ceiling,
where C: Ceiling
{
/// Assigns a ceiling `C` to the `peripheral`
///
/// # Safety
///
/// You MUST not create two resources that point to the same peripheral
pub const unsafe fn new(peripheral: cortex_m::peripheral::Peripheral<P>,)
-> Self {
pub const unsafe fn new(peripheral: cortex_m::peripheral::Peripheral<P>) -> Self {
Peripheral {
_ceiling: PhantomData,
peripheral: peripheral,
@ -195,49 +166,37 @@ where
impl<Periph, CEILING> Peripheral<Periph, C<CEILING>> {
/// See [Resource.borrow](./struct.Resource.html#method.borrow)
pub fn borrow<'cs, PRIORITY, SCEILING>(
&'static self,
_priority: &P<PRIORITY>,
_system_ceiling: &'cs C<SCEILING>,
) -> Ref<'cs, Periph>
where
SCEILING: GreaterThanOrEqual<CEILING>,
CEILING: GreaterThanOrEqual<PRIORITY>,
pub fn borrow<'cs, PRIORITY, SCEILING>(&'static self,
_priority: &P<PRIORITY>,
_system_ceiling: &'cs C<SCEILING>)
-> Ref<'cs, Periph>
where SCEILING: GreaterThanOrEqual<CEILING>,
CEILING: GreaterThanOrEqual<PRIORITY>
{
unsafe { Ref::new(&*self.peripheral.get()) }
}
/// See [Resource.claim](./struct.Resource.html#method.claim)
pub fn claim<'task, PRIORITY>(
&'static self,
_priority: &'task P<PRIORITY>,
) -> Ref<'task, Periph>
where
CEILING: Cmp<PRIORITY, Output = Equal>,
pub fn claim<'task, PRIORITY>(&'static self,
_priority: &'task P<PRIORITY>)
-> Ref<'task, Periph>
where CEILING: Cmp<PRIORITY, Output = Equal>
{
unsafe { Ref::new(&*self.peripheral.get()) }
}
/// See [Resource.lock](./struct.Resource.html#method.lock)
#[cfg(not(thumbv6m))]
pub fn lock<R, PRIORITY, F>(
&'static self,
_priority: &P<PRIORITY>,
f: F,
) -> R
where
F: FnOnce(Ref<Periph>, C<CEILING>) -> R,
CEILING: Cmp<PRIORITY, Output = Greater> + Cmp<UMAX, Output = Less>
+ Level,
pub fn lock<R, PRIORITY, F>(&'static self, _priority: &P<PRIORITY>, f: F) -> R
where F: FnOnce(Ref<Periph>, C<CEILING>) -> R,
CEILING: Cmp<PRIORITY, Output = Greater> + Cmp<UMAX, Output = Less> + Level
{
unsafe {
let old_basepri = basepri::read();
basepri_max::write(<CEILING>::hw());
barrier!();
let ret = f(
Ref::new(&*self.peripheral.get()),
C { _marker: PhantomData },
);
let ret = f(Ref::new(&*self.peripheral.get()),
C { _marker: PhantomData });
barrier!();
basepri::write(old_basepri);
ret
@ -245,18 +204,13 @@ impl<Periph, CEILING> Peripheral<Periph, C<CEILING>> {
}
}
unsafe impl<T, C> Sync for Peripheral<T, C>
where
C: Ceiling,
{
}
unsafe impl<T, C> Sync for Peripheral<T, C> where C: Ceiling {}
/// A global critical section
///
/// No task can preempt this critical section
pub fn critical<R, F>(f: F) -> R
where
F: FnOnce(CMAX) -> R,
where F: FnOnce(CMAX) -> R
{
let primask = ::cortex_m::register::primask::read();
::cortex_m::interrupt::disable();
@ -274,9 +228,8 @@ where
/// Requests the execution of a `task`
pub fn request<T, P>(_task: fn(T, P))
where
T: Context + Nr,
P: Priority,
where T: Context + Nr,
P: Priority
{
let nvic = unsafe { &*NVIC.get() };
@ -310,8 +263,7 @@ pub struct P<T> {
}
impl<T> P<T>
where
T: Level,
where T: Level
{
#[doc(hidden)]
pub fn hw() -> u8 {
@ -342,10 +294,22 @@ pub unsafe trait Level {
/// DO NOT IMPLEMENT THIS TRAIT YOURSELF
pub unsafe trait Priority {}
fn logical2hw(logical: u8) -> u8 {
/// Convert a logical priority to a shifted hardware prio
/// as used by the NVIC and basepri registers
/// Notice, wrapping causes a panic due to u8
pub fn logical2hw(logical: u8) -> u8 {
((1 << PRIORITY_BITS) - logical) << (8 - PRIORITY_BITS)
}
/// Convert a shifted hardware prio to a logical priority
/// as used by the NVIC and basepri registers
/// Notice, wrapping causes a panic due to u8
pub fn hw2logical(hw: u8) -> u8 {
(1 << PRIORITY_BITS) - (hw >> (8 - PRIORITY_BITS))
}
/// Priority 0, the lowest priority
pub type P0 = P<::typenum::U0>;