aboutsummaryrefslogtreecommitdiff
path: root/src
diff options
context:
space:
mode:
Diffstat (limited to 'src')
-rw-r--r--src/lib.rs221
1 files changed, 180 insertions, 41 deletions
diff --git a/src/lib.rs b/src/lib.rs
index b03674b..353d630 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -16,6 +16,7 @@ use cortex_m::register::{basepri, basepri_max};
use core::cell::UnsafeCell;
use core::marker::PhantomData;
+use core::ptr;
// NOTE Only the 4 highest bits of the priority byte (BASEPRI / NVIC.IPR) are
// considered when determining priorities.
@@ -23,26 +24,28 @@ const PRIORITY_BITS: u8 = 4;
// XXX Do we need memory / instruction / compiler barriers here?
#[inline(always)]
-unsafe fn claim<T, R, F>(f: F, res: *const T, ceiling: u8) -> R
+unsafe fn lock<T, R, C, F>(f: F, res: *const T, ceiling: u8) -> R
where
- F: FnOnce(&T) -> R,
+ C: Ceiling,
+ F: FnOnce(&T, C) -> R,
{
let old_basepri = basepri::read();
basepri_max::write(ceiling);
- let ret = f(&*res);
+ let ret = f(&*res, ptr::read(0 as *const _));
basepri::write(old_basepri);
ret
}
// XXX Do we need memory / instruction / compiler barriers here?
#[inline(always)]
-unsafe fn claim_mut<T, R, F>(f: F, res: *mut T, ceiling: u8) -> R
+unsafe fn lock_mut<T, R, C, F>(f: F, res: *mut T, ceiling: u8) -> R
where
- F: FnOnce(&mut T) -> R,
+ C: Ceiling,
+ F: FnOnce(&mut T, C) -> R,
{
let old_basepri = basepri::read();
basepri_max::write(ceiling);
- let ret = f(&mut *res);
+ let ret = f(&mut *res, ptr::read(0 as *const _));
basepri::write(old_basepri);
ret
}
@@ -80,47 +83,46 @@ where
C: Ceiling,
{
/// Borrows the resource without locking
- // TODO document unsafety
- pub unsafe fn borrow<'ctxt, Ctxt>(
- &'static self,
- _ctxt: &'ctxt Ctxt,
- ) -> &'ctxt P
+ ///
+ /// NOTE The system ceiling must be higher than this resource ceiling
+ pub fn borrow<'l, SC>(&'static self, _system_ceiling: &'l SC) -> &'l P
where
- Ctxt: Context,
+ SC: HigherThan<C>,
{
- &*self.peripheral.get()
+ unsafe { &*self.peripheral.get() }
}
/// Mutably borrows the resource without locking
- // TODO document unsafety
- pub unsafe fn borrow_mut<'ctxt, Ctxt>(
+ ///
+ /// NOTE The system ceiling must be higher than this resource ceiling
+ pub fn borrow_mut<'l, SC>(
&'static self,
- _ctxt: &'ctxt mut Ctxt,
- ) -> &'ctxt mut P
+ _system_ceiling: &'l mut SC,
+ ) -> &'l mut P
where
- Ctxt: Context,
+ SC: HigherThan<C>,
{
- &mut *self.peripheral.get()
+ unsafe { &mut *self.peripheral.get() }
}
/// Locks the resource, preventing tasks with priority lower than `Ceiling`
/// from preempting the current task
pub fn lock<R, F, Ctxt>(&'static self, _ctxt: &Ctxt, f: F) -> R
where
- F: FnOnce(&P) -> R,
+ F: FnOnce(&P, C) -> R,
Ctxt: Context,
{
- unsafe { claim(f, self.peripheral.get(), C::ceiling()) }
+ unsafe { lock(f, self.peripheral.get(), C::ceiling()) }
}
/// Mutably locks the resource, preventing tasks with priority lower than
/// `Ceiling` from preempting the current task
pub fn lock_mut<R, F, Ctxt>(&'static self, _ctxt: &mut Ctxt, f: F) -> R
where
- F: FnOnce(&mut P) -> R,
+ F: FnOnce(&mut P, C) -> R,
Ctxt: Context,
{
- unsafe { claim_mut(f, self.peripheral.get(), C::ceiling()) }
+ unsafe { lock_mut(f, self.peripheral.get(), C::ceiling()) }
}
}
@@ -179,42 +181,40 @@ where
/// from preempting the current task
pub fn lock<F, R, Ctxt>(&'static self, _ctxt: &Ctxt, f: F) -> R
where
- F: FnOnce(&T) -> R,
+ F: FnOnce(&T, C) -> R,
Ctxt: Context,
{
- unsafe { claim(f, self.data.get(), C::ceiling()) }
+ unsafe { lock(f, self.data.get(), C::ceiling()) }
}
/// Mutably locks the resource, preventing tasks with priority lower than
/// `Ceiling` from preempting the current task
pub fn lock_mut<F, R, Ctxt>(&'static self, _ctxt: &mut Ctxt, f: F) -> R
where
- F: FnOnce(&mut T) -> R,
+ F: FnOnce(&mut T, C) -> R,
Ctxt: Context,
{
- unsafe { claim_mut(f, self.data.get(), C::ceiling()) }
+ unsafe { lock_mut(f, self.data.get(), C::ceiling()) }
}
- /// Borrows the resource, without locking
- pub unsafe fn borrow<'ctxt, Ctxt>(
- &'static self,
- _ctxt: &'ctxt Ctxt,
- ) -> &'ctxt T
+ /// Borrows the resource without locking
+ ///
+ /// NOTE The system ceiling must be higher than this resource ceiling
+ pub fn borrow<'l, SC>(&'static self, _system_ceiling: &'l SC) -> &'l T
where
- Ctxt: Context,
+ SC: HigherThan<C>,
{
- &*self.data.get()
+ unsafe { &*self.data.get() }
}
- /// Mutably borrows the resource, without locking
- pub unsafe fn borrow_mut<'ctxt, Ctxt>(
- &'static self,
- _ctxt: &'ctxt mut Ctxt,
- ) -> &'ctxt mut T
+ /// Mutably borrows the resource without locking
+ ///
+ /// NOTE The system ceiling must be higher than this resource ceiling
+ pub fn borrow_mut<'l, SC>(&'static self, _ctxt: &'l mut SC) -> &'l mut T
where
- Ctxt: Context,
+ SC: HigherThan<C>,
{
- &mut *self.data.get()
+ unsafe { &mut *self.data.get() }
}
}
@@ -348,93 +348,232 @@ pub unsafe trait Ceiling {
}
/// Usable as a ceiling
+// XXX this should be a "closed" trait
pub unsafe trait CeilingLike {}
+/// This ceiling is lower than `C`
+// XXX this should be a "closed" trait
+pub unsafe trait HigherThan<C> {}
+
+unsafe impl HigherThan<C1> for C2 {}
+unsafe impl HigherThan<C1> for C3 {}
+unsafe impl HigherThan<C1> for C4 {}
+unsafe impl HigherThan<C1> for C5 {}
+unsafe impl HigherThan<C1> for C6 {}
+unsafe impl HigherThan<C1> for C7 {}
+unsafe impl HigherThan<C1> for C8 {}
+unsafe impl HigherThan<C1> for C9 {}
+unsafe impl HigherThan<C1> for C10 {}
+unsafe impl HigherThan<C1> for C11 {}
+unsafe impl HigherThan<C1> for C12 {}
+unsafe impl HigherThan<C1> for C13 {}
+unsafe impl HigherThan<C1> for C14 {}
+unsafe impl HigherThan<C1> for C15 {}
+
+unsafe impl HigherThan<C2> for C3 {}
+unsafe impl HigherThan<C2> for C4 {}
+unsafe impl HigherThan<C2> for C5 {}
+unsafe impl HigherThan<C2> for C6 {}
+unsafe impl HigherThan<C2> for C7 {}
+unsafe impl HigherThan<C2> for C8 {}
+unsafe impl HigherThan<C2> for C9 {}
+unsafe impl HigherThan<C2> for C10 {}
+unsafe impl HigherThan<C2> for C11 {}
+unsafe impl HigherThan<C2> for C12 {}
+unsafe impl HigherThan<C2> for C13 {}
+unsafe impl HigherThan<C2> for C14 {}
+unsafe impl HigherThan<C2> for C15 {}
+
+unsafe impl HigherThan<C3> for C4 {}
+unsafe impl HigherThan<C3> for C5 {}
+unsafe impl HigherThan<C3> for C6 {}
+unsafe impl HigherThan<C3> for C7 {}
+unsafe impl HigherThan<C3> for C8 {}
+unsafe impl HigherThan<C3> for C9 {}
+unsafe impl HigherThan<C3> for C10 {}
+unsafe impl HigherThan<C3> for C11 {}
+unsafe impl HigherThan<C3> for C12 {}
+unsafe impl HigherThan<C3> for C13 {}
+unsafe impl HigherThan<C3> for C14 {}
+unsafe impl HigherThan<C3> for C15 {}
+
+unsafe impl HigherThan<C4> for C5 {}
+unsafe impl HigherThan<C4> for C6 {}
+unsafe impl HigherThan<C4> for C7 {}
+unsafe impl HigherThan<C4> for C8 {}
+unsafe impl HigherThan<C4> for C9 {}
+unsafe impl HigherThan<C4> for C10 {}
+unsafe impl HigherThan<C4> for C11 {}
+unsafe impl HigherThan<C4> for C12 {}
+unsafe impl HigherThan<C4> for C13 {}
+unsafe impl HigherThan<C4> for C14 {}
+unsafe impl HigherThan<C4> for C15 {}
+
+unsafe impl HigherThan<C5> for C6 {}
+unsafe impl HigherThan<C5> for C7 {}
+unsafe impl HigherThan<C5> for C8 {}
+unsafe impl HigherThan<C5> for C9 {}
+unsafe impl HigherThan<C5> for C10 {}
+unsafe impl HigherThan<C5> for C11 {}
+unsafe impl HigherThan<C5> for C12 {}
+unsafe impl HigherThan<C5> for C13 {}
+unsafe impl HigherThan<C5> for C14 {}
+unsafe impl HigherThan<C5> for C15 {}
+
+unsafe impl HigherThan<C6> for C7 {}
+unsafe impl HigherThan<C6> for C8 {}
+unsafe impl HigherThan<C6> for C9 {}
+unsafe impl HigherThan<C6> for C10 {}
+unsafe impl HigherThan<C6> for C11 {}
+unsafe impl HigherThan<C6> for C12 {}
+unsafe impl HigherThan<C6> for C13 {}
+unsafe impl HigherThan<C6> for C14 {}
+unsafe impl HigherThan<C6> for C15 {}
+
+unsafe impl HigherThan<C7> for C8 {}
+unsafe impl HigherThan<C7> for C9 {}
+unsafe impl HigherThan<C7> for C10 {}
+unsafe impl HigherThan<C7> for C11 {}
+unsafe impl HigherThan<C7> for C12 {}
+unsafe impl HigherThan<C7> for C13 {}
+unsafe impl HigherThan<C7> for C14 {}
+unsafe impl HigherThan<C7> for C15 {}
+
+unsafe impl HigherThan<C8> for C9 {}
+unsafe impl HigherThan<C8> for C10 {}
+unsafe impl HigherThan<C8> for C11 {}
+unsafe impl HigherThan<C8> for C12 {}
+unsafe impl HigherThan<C8> for C13 {}
+unsafe impl HigherThan<C8> for C14 {}
+unsafe impl HigherThan<C8> for C15 {}
+
+unsafe impl HigherThan<C9> for C10 {}
+unsafe impl HigherThan<C9> for C11 {}
+unsafe impl HigherThan<C9> for C12 {}
+unsafe impl HigherThan<C9> for C13 {}
+unsafe impl HigherThan<C9> for C14 {}
+unsafe impl HigherThan<C9> for C15 {}
+
+unsafe impl HigherThan<C10> for C11 {}
+unsafe impl HigherThan<C10> for C12 {}
+unsafe impl HigherThan<C10> for C13 {}
+unsafe impl HigherThan<C10> for C14 {}
+unsafe impl HigherThan<C10> for C15 {}
+
+unsafe impl HigherThan<C11> for C12 {}
+unsafe impl HigherThan<C11> for C13 {}
+unsafe impl HigherThan<C11> for C14 {}
+unsafe impl HigherThan<C11> for C15 {}
+
+unsafe impl HigherThan<C12> for C13 {}
+unsafe impl HigherThan<C12> for C14 {}
+unsafe impl HigherThan<C12> for C15 {}
+
+unsafe impl HigherThan<C13> for C14 {}
+unsafe impl HigherThan<C13> for C15 {}
+
+unsafe impl HigherThan<C14> for C15 {}
+
unsafe impl Ceiling for C1 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 1) << 4
}
}
unsafe impl Ceiling for C2 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 2) << 4
}
}
unsafe impl Ceiling for C3 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 3) << 4
}
}
unsafe impl Ceiling for C4 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 4) << 4
}
}
unsafe impl Ceiling for C5 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 5) << 4
}
}
unsafe impl Ceiling for C6 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 6) << 4
}
}
unsafe impl Ceiling for C7 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 7) << 4
}
}
unsafe impl Ceiling for C8 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 8) << 4
}
}
unsafe impl Ceiling for C9 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 9) << 4
}
}
unsafe impl Ceiling for C10 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 10) << 4
}
}
unsafe impl Ceiling for C11 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 11) << 4
}
}
unsafe impl Ceiling for C12 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 12) << 4
}
}
unsafe impl Ceiling for C13 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 13) << 4
}
}
unsafe impl Ceiling for C14 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 14) << 4
}
}
unsafe impl Ceiling for C15 {
+ #[inline(always)]
fn ceiling() -> u8 {
((1 << 4) - 15) << 4
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-12-27 09:29:08 +0000