executor: add faster ARM-specific impl.

Does a wake+poll in 79 cycles in nrf52840.

ci.sh

@@ -218,6 +218,7 @@ cargo batch  \
 rm out/tests/stm32wb55rg/wpan_mac
 rm out/tests/stm32wb55rg/wpan_ble
 
+
 # unstable, I think it's running out of RAM?
 rm out/tests/stm32f207zg/eth
 

cyw43-pio/src/lib.rs

@@ -1,6 +1,6 @@
 #![no_std]
-#![allow(incomplete_features)]
 #![feature(async_fn_in_trait)]
+#![allow(stable_features, unknown_lints, async_fn_in_trait)]
 
 use core::slice;
 

cyw43/Cargo.toml

@@ -12,7 +12,7 @@ firmware-logs = []
 
 [dependencies]
 embassy-time = { version = "0.1.5", path = "../embassy-time"}
-embassy-sync = { version = "0.3.0", path = "../embassy-sync"}
+embassy-sync = { version = "0.4.0", path = "../embassy-sync"}
 embassy-futures = { version = "0.1.0", path = "../embassy-futures"}
 embassy-net-driver-channel = { version = "0.2.0", path = "../embassy-net-driver-channel"}
 

cyw43/src/control.rs

@@ -4,7 +4,6 @@ use embassy_net_driver_channel as ch;
 use embassy_net_driver_channel::driver::{HardwareAddress, LinkState};
 use embassy_time::Timer;
 
-pub use crate::bus::SpiBusCyw43;
 use crate::consts::*;
 use crate::events::{Event, EventSubscriber, Events};
 use crate::fmt::Bytes;

cyw43/src/lib.rs

@@ -1,7 +1,7 @@
 #![no_std]
 #![no_main]
-#![allow(incomplete_features)]
 #![feature(async_fn_in_trait, type_alias_impl_trait, concat_bytes)]
+#![allow(stable_features, unknown_lints, async_fn_in_trait)]
 #![deny(unused_must_use)]
 
 // This mod MUST go first, so that the others see its macros.

embassy-boot/boot/Cargo.toml

@@ -28,7 +28,7 @@ digest = "0.10"
 log = { version = "0.4", optional = true  }
 ed25519-dalek = { version = "1.0.1", default_features = false, features = ["u32_backend"], optional = true }
 embassy-embedded-hal = { version = "0.1.0", path = "../../embassy-embedded-hal" }
-embassy-sync = { version = "0.3.0", path = "../../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../../embassy-sync" }
 embedded-storage = "0.3.0"
 embedded-storage-async = { version = "0.4.0", optional = true }
 salty = { git = "https://github.com/ycrypto/salty.git", rev = "a9f17911a5024698406b75c0fac56ab5ccf6a8c7", optional = true }

embassy-boot/boot/src/lib.rs

@@ -1,4 +1,5 @@
 #![cfg_attr(feature = "nightly", feature(async_fn_in_trait))]
+#![cfg_attr(feature = "nightly", allow(stable_features, unknown_lints, async_fn_in_trait))]
 #![no_std]
 #![warn(missing_docs)]
 #![doc = include_str!("../README.md")]

embassy-boot/nrf/Cargo.toml

@@ -16,7 +16,7 @@ target = "thumbv7em-none-eabi"
 [dependencies]
 defmt = { version = "0.3", optional = true }
 
-embassy-sync = { path = "../../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../../embassy-sync" }
 embassy-nrf = { path = "../../embassy-nrf" }
 embassy-boot = { path = "../boot", default-features = false }
 cortex-m = { version = "0.7.6" }

embassy-boot/rp/Cargo.toml

@@ -17,7 +17,7 @@ defmt = { version = "0.3", optional = true }
 defmt-rtt = { version = "0.4", optional = true }
 log = { version = "0.4", optional = true }
 
-embassy-sync = { path = "../../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../../embassy-sync" }
 embassy-rp = { path = "../../embassy-rp", default-features = false }
 embassy-boot = { path = "../boot", default-features = false }
 embassy-time = { path = "../../embassy-time" }

embassy-boot/stm32/Cargo.toml

@@ -18,7 +18,7 @@ defmt = { version = "0.3", optional = true }
 defmt-rtt = { version = "0.4", optional = true }
 log = { version = "0.4", optional = true }
 
-embassy-sync = { path = "../../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../../embassy-sync" }
 embassy-stm32 = { path = "../../embassy-stm32", default-features = false }
 embassy-boot = { path = "../boot", default-features = false }
 cortex-m = { version = "0.7.6" }

embassy-embedded-hal/Cargo.toml

@@ -20,7 +20,7 @@ default = ["time"]
 
 [dependencies]
 embassy-futures = { version = "0.1.0", path = "../embassy-futures", optional = true }
-embassy-sync = { version = "0.3.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../embassy-sync" }
 embassy-time = { version = "0.1.5", path = "../embassy-time", optional = true }
 embedded-hal-02 = { package = "embedded-hal", version = "0.2.6", features = [
     "unproven",

embassy-embedded-hal/src/lib.rs

@@ -1,5 +1,6 @@
 #![cfg_attr(not(feature = "std"), no_std)]
-#![cfg_attr(feature = "nightly", feature(async_fn_in_trait, try_blocks))]
+#![cfg_attr(feature = "nightly", feature(async_fn_in_trait, impl_trait_projections, try_blocks))]
+#![cfg_attr(feature = "nightly", allow(stable_features, unknown_lints, async_fn_in_trait))]
 #![warn(missing_docs)]
 
 //! Utilities to use `embedded-hal` traits with Embassy.

embassy-executor/CHANGELOG.md

@@ -5,6 +5,20 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## 0.3.3 - 2023-11-15
+
+- Add `main` macro reexport for Xtensa arch.
+- Remove use of `atomic-polyfill`. The executor now has multiple implementations of its internal data structures for cases where the target supports atomics or doesn't.
+
+## 0.3.2 - 2023-11-06
+
+- Use `atomic-polyfill` for `riscv32`
+- Removed unused dependencies (static_cell, futures-util)
+
+## 0.3.1 - 2023-11-01
+
+- Fix spurious "Found waker not created by the Embassy executor" error in recent nightlies.
+
 ## 0.3.0 - 2023-08-25
 
 - Replaced Pender. Implementations now must define an extern function called `__pender`.

embassy-executor/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "embassy-executor"
-version = "0.3.0"
+version = "0.3.3"
 edition = "2021"
 license = "MIT OR Apache-2.0"
 description = "async/await executor designed for embedded usage"
@@ -34,7 +34,7 @@ _arch = [] # some arch was picked
 arch-std = ["_arch", "critical-section/std"]
 arch-cortex-m = ["_arch", "dep:cortex-m"]
 arch-xtensa = ["_arch"]
-arch-riscv32 = ["_arch"]
+arch-riscv32 = ["_arch", "dep:portable-atomic"]
 arch-wasm = ["_arch", "dep:wasm-bindgen", "dep:js-sys"]
 
 # Enable the thread-mode executor (using WFE/SEV in Cortex-M, WFI in other embedded archs)
@@ -57,12 +57,13 @@ defmt = { version = "0.3", optional = true }
 log = { version = "0.4.14", optional = true }
 rtos-trace = { version = "0.1.2", optional = true }
 
-futures-util = { version = "0.3.17", default-features = false }
 embassy-macros = { version = "0.2.1", path = "../embassy-macros" }
 embassy-time = { version = "0.1.5", path = "../embassy-time", optional = true}
-atomic-polyfill = "1.0.1"
 critical-section = "1.1"
-static_cell = "1.1"
+
+# needed for riscv
+# remove when https://github.com/rust-lang/rust/pull/114499 is merged
+portable-atomic = { version = "1.5", optional = true }
 
 # arch-cortex-m dependencies
 cortex-m = { version = "0.7.6", optional = true }

embassy-executor/src/arch/cortex_m.rs

@@ -115,12 +115,12 @@ mod thread {
 pub use interrupt::*;
 #[cfg(feature = "executor-interrupt")]
 mod interrupt {
-    use core::cell::UnsafeCell;
+    use core::cell::{Cell, UnsafeCell};
     use core::mem::MaybeUninit;
 
-    use atomic_polyfill::{AtomicBool, Ordering};
     use cortex_m::interrupt::InterruptNumber;
     use cortex_m::peripheral::NVIC;
+    use critical_section::Mutex;
 
     use crate::raw;
 
@@ -146,7 +146,7 @@ mod interrupt {
     /// It is somewhat more complex to use, it's recommended to use the thread-mode
     /// [`Executor`] instead, if it works for your use case.
     pub struct InterruptExecutor {
-        started: AtomicBool,
+        started: Mutex<Cell<bool>>,
         executor: UnsafeCell<MaybeUninit<raw::Executor>>,
     }
 
@@ -158,7 +158,7 @@ mod interrupt {
         #[inline]
         pub const fn new() -> Self {
             Self {
-                started: AtomicBool::new(false),
+                started: Mutex::new(Cell::new(false)),
                 executor: UnsafeCell::new(MaybeUninit::uninit()),
             }
         }
@@ -167,7 +167,8 @@ mod interrupt {
         ///
         /// # Safety
         ///
-        /// You MUST call this from the interrupt handler, and from nowhere else.
+        /// - You MUST call this from the interrupt handler, and from nowhere else.
+        /// - You must not call this before calling `start()`.
         pub unsafe fn on_interrupt(&'static self) {
             let executor = unsafe { (&*self.executor.get()).assume_init_ref() };
             executor.poll();
@@ -196,11 +197,7 @@ mod interrupt {
         /// do it after.
         ///
         pub fn start(&'static self, irq: impl InterruptNumber) -> crate::SendSpawner {
-            if self
-                .started
-                .compare_exchange(false, true, Ordering::Acquire, Ordering::Relaxed)
-                .is_err()
-            {
+            if critical_section::with(|cs| self.started.borrow(cs).replace(true)) {
                 panic!("InterruptExecutor::start() called multiple times on the same executor.");
             }
 
@@ -222,10 +219,10 @@ mod interrupt {
         /// This returns a [`SendSpawner`] you can use to spawn tasks on this
         /// executor.
         ///
-        /// This MUST only be called on an executor that has already been spawned.
+        /// This MUST only be called on an executor that has already been started.
         /// The function will panic otherwise.
         pub fn spawner(&'static self) -> crate::SendSpawner {
-            if !self.started.load(Ordering::Acquire) {
+            if !critical_section::with(|cs| self.started.borrow(cs).get()) {
                 panic!("InterruptExecutor::spawner() called on uninitialized executor.");
             }
             let executor = unsafe { (&*self.executor.get()).assume_init_ref() };

embassy-executor/src/arch/riscv32.rs

@@ -6,10 +6,10 @@ pub use thread::*;
 #[cfg(feature = "executor-thread")]
 mod thread {
     use core::marker::PhantomData;
-    use core::sync::atomic::{AtomicBool, Ordering};
 
     #[cfg(feature = "nightly")]
     pub use embassy_macros::main_riscv as main;
+    use portable_atomic::{AtomicBool, Ordering};
 
     use crate::{raw, Spawner};
 

embassy-executor/src/arch/xtensa.rs

@@ -8,6 +8,9 @@ mod thread {
     use core::marker::PhantomData;
     use core::sync::atomic::{AtomicBool, Ordering};
 
+    #[cfg(feature = "nightly")]
+    pub use embassy_macros::main_riscv as main;
+
     use crate::{raw, Spawner};
 
     /// global atomic used to keep track of whether there is work to do since sev() is not available on Xtensa

embassy-executor/src/lib.rs

@@ -33,6 +33,7 @@ check_at_most_one!("arch-cortex-m", "arch-riscv32", "arch-xtensa", "arch-std", "
 mod arch;
 
 #[cfg(feature = "_arch")]
+#[allow(unused_imports)] // don't warn if the module is empty.
 pub use arch::*;
 
 pub mod raw;
@@ -46,7 +47,6 @@ pub use spawner::*;
 pub mod _export {
     #[cfg(feature = "rtos-trace")]
     pub use rtos_trace::trace;
-    pub use static_cell::StaticCell;
 
     /// Expands the given block of code when `embassy-executor` is compiled with
     /// the `rtos-trace-interrupt` feature.

embassy-executor/src/raw/mod.rs

@@ -7,7 +7,15 @@
 //! Using this module requires respecting subtle safety contracts. If you can, prefer using the safe
 //! [executor wrappers](crate::Executor) and the [`embassy_executor::task`](embassy_macros::task) macro, which are fully safe.
 
+#[cfg_attr(target_has_atomic = "ptr", path = "run_queue_atomics.rs")]
+#[cfg_attr(not(target_has_atomic = "ptr"), path = "run_queue_critical_section.rs")]
 mod run_queue;
+
+#[cfg_attr(all(cortex_m, target_has_atomic = "8"), path = "state_atomics_arm.rs")]
+#[cfg_attr(all(not(cortex_m), target_has_atomic = "8"), path = "state_atomics.rs")]
+#[cfg_attr(not(target_has_atomic = "8"), path = "state_critical_section.rs")]
+mod state;
+
 #[cfg(feature = "integrated-timers")]
 mod timer_queue;
 pub(crate) mod util;
@@ -21,7 +29,6 @@ use core::pin::Pin;
 use core::ptr::NonNull;
 use core::task::{Context, Poll};
 
-use atomic_polyfill::{AtomicU32, Ordering};
 #[cfg(feature = "integrated-timers")]
 use embassy_time::driver::{self, AlarmHandle};
 #[cfg(feature = "integrated-timers")]
@@ -30,21 +37,14 @@ use embassy_time::Instant;
 use rtos_trace::trace;
 
 use self::run_queue::{RunQueue, RunQueueItem};
+use self::state::State;
 use self::util::{SyncUnsafeCell, UninitCell};
 pub use self::waker::task_from_waker;
 use super::SpawnToken;
 
-/// Task is spawned (has a future)
-pub(crate) const STATE_SPAWNED: u32 = 1 << 0;
-/// Task is in the executor run queue
-pub(crate) const STATE_RUN_QUEUED: u32 = 1 << 1;
-/// Task is in the executor timer queue
-#[cfg(feature = "integrated-timers")]
-pub(crate) const STATE_TIMER_QUEUED: u32 = 1 << 2;
-
 /// Raw task header for use in task pointers.
 pub(crate) struct TaskHeader {
-    pub(crate) state: AtomicU32,
+    pub(crate) state: State,
     pub(crate) run_queue_item: RunQueueItem,
     pub(crate) executor: SyncUnsafeCell<Option<&'static SyncExecutor>>,
     poll_fn: SyncUnsafeCell<Option<unsafe fn(TaskRef)>>,
@@ -116,7 +116,7 @@ impl<F: Future + 'static> TaskStorage<F> {
     pub const fn new() -> Self {
         Self {
             raw: TaskHeader {
-                state: AtomicU32::new(0),
+                state: State::new(),
                 run_queue_item: RunQueueItem::new(),
                 executor: SyncUnsafeCell::new(None),
                 // Note: this is lazily initialized so that a static `TaskStorage` will go in `.bss`
@@ -161,7 +161,7 @@ impl<F: Future + 'static> TaskStorage<F> {
         match future.poll(&mut cx) {
             Poll::Ready(_) => {
                 this.future.drop_in_place();
-                this.raw.state.fetch_and(!STATE_SPAWNED, Ordering::AcqRel);
+                this.raw.state.despawn();
 
                 #[cfg(feature = "integrated-timers")]
                 this.raw.expires_at.set(Instant::MAX);
@@ -193,11 +193,7 @@ impl<F: Future + 'static> AvailableTask<F> {
     ///
     /// This function returns `None` if a task has already been spawned and has not finished running.
     pub fn claim(task: &'static TaskStorage<F>) -> Option<Self> {
-        task.raw
-            .state
-            .compare_exchange(0, STATE_SPAWNED | STATE_RUN_QUEUED, Ordering::AcqRel, Ordering::Acquire)
-            .ok()
-            .map(|_| Self { task })
+        task.raw.state.spawn().then(|| Self { task })
     }
 
     fn initialize_impl<S>(self, future: impl FnOnce() -> F) -> SpawnToken<S> {
@@ -394,8 +390,7 @@ impl SyncExecutor {
                 #[cfg(feature = "integrated-timers")]
                 task.expires_at.set(Instant::MAX);
 
-                let state = task.state.fetch_and(!STATE_RUN_QUEUED, Ordering::AcqRel);
-                if state & STATE_SPAWNED == 0 {
+                if !task.state.run_dequeue() {
                     // If task is not running, ignore it. This can happen in the following scenario:
                     //   - Task gets dequeued, poll starts
                     //   - While task is being polled, it gets woken. It gets placed in the queue.
@@ -546,18 +541,7 @@ impl Executor {
 /// You can obtain a `TaskRef` from a `Waker` using [`task_from_waker`].
 pub fn wake_task(task: TaskRef) {
     let header = task.header();
-
-    let res = header.state.fetch_update(Ordering::SeqCst, Ordering::SeqCst, |state| {
-        // If already scheduled, or if not started,
-        if (state & STATE_RUN_QUEUED != 0) || (state & STATE_SPAWNED == 0) {
-            None
-        } else {
-            // Mark it as scheduled
-            Some(state | STATE_RUN_QUEUED)
-        }
-    });
-
-    if res.is_ok() {
+    if header.state.run_enqueue() {
         // We have just marked the task as scheduled, so enqueue it.
         unsafe {
             let executor = header.executor.get().unwrap_unchecked();
@@ -571,18 +555,7 @@ pub fn wake_task(task: TaskRef) {
 /// You can obtain a `TaskRef` from a `Waker` using [`task_from_waker`].
 pub fn wake_task_no_pend(task: TaskRef) {
     let header = task.header();
-
-    let res = header.state.fetch_update(Ordering::SeqCst, Ordering::SeqCst, |state| {
-        // If already scheduled, or if not started,
-        if (state & STATE_RUN_QUEUED != 0) || (state & STATE_SPAWNED == 0) {
-            None
-        } else {
-            // Mark it as scheduled
-            Some(state | STATE_RUN_QUEUED)
-        }
-    });
-
-    if res.is_ok() {
+    if header.state.run_enqueue() {
         // We have just marked the task as scheduled, so enqueue it.
         unsafe {
             let executor = header.executor.get().unwrap_unchecked();

embassy-executor/src/raw/run_queue_atomics.rs

@@ -1,7 +1,6 @@
 use core::ptr;
 use core::ptr::NonNull;
-
-use atomic_polyfill::{AtomicPtr, Ordering};
+use core::sync::atomic::{AtomicPtr, Ordering};
 
 use super::{TaskHeader, TaskRef};
 use crate::raw::util::SyncUnsafeCell;

embassy-executor/src/raw/run_queue_critical_section.rs

@@ -0,0 +1,75 @@
+use core::cell::Cell;
+
+use critical_section::{CriticalSection, Mutex};
+
+use super::TaskRef;
+
+pub(crate) struct RunQueueItem {
+    next: Mutex<Cell<Option<TaskRef>>>,
+}
+
+impl RunQueueItem {
+    pub const fn new() -> Self {
+        Self {
+            next: Mutex::new(Cell::new(None)),
+        }
+    }
+}
+
+/// Atomic task queue using a very, very simple lock-free linked-list queue:
+///
+/// To enqueue a task, task.next is set to the old head, and head is atomically set to task.
+///
+/// Dequeuing is done in batches: the queue is emptied by atomically replacing head with
+/// null. Then the batch is iterated following the next pointers until null is reached.
+///
+/// Note that batches will be iterated in the reverse order as they were enqueued. This is OK
+/// for our purposes: it can't create fairness problems since the next batch won't run until the
+/// current batch is completely processed, so even if a task enqueues itself instantly (for example
+/// by waking its own waker) can't prevent other tasks from running.
+pub(crate) struct RunQueue {
+    head: Mutex<Cell<Option<TaskRef>>>,
+}
+
+impl RunQueue {
+    pub const fn new() -> Self {
+        Self {
+            head: Mutex::new(Cell::new(None)),
+        }
+    }
+
+    /// Enqueues an item. Returns true if the queue was empty.
+    ///
+    /// # Safety
+    ///
+    /// `item` must NOT be already enqueued in any queue.
+    #[inline(always)]
+    pub(crate) unsafe fn enqueue(&self, task: TaskRef) -> bool {
+        critical_section::with(|cs| {
+            let prev = self.head.borrow(cs).replace(Some(task));
+            task.header().run_queue_item.next.borrow(cs).set(prev);
+
+            prev.is_none()
+        })
+    }
+
+    /// Empty the queue, then call `on_task` for each task that was in the queue.
+    /// NOTE: It is OK for `on_task` to enqueue more tasks. In this case they're left in the queue
+    /// and will be processed by the *next* call to `dequeue_all`, *not* the current one.
+    pub(crate) fn dequeue_all(&self, on_task: impl Fn(TaskRef)) {
+        // Atomically empty the queue.
+        let mut next = critical_section::with(|cs| self.head.borrow(cs).take());
+
+        // Iterate the linked list of tasks that were previously in the queue.
+        while let Some(task) = next {
+            // If the task re-enqueues itself, the `next` pointer will get overwritten.
+            // Therefore, first read the next pointer, and only then process the task.
+
+            // safety: we know if the task is enqueued, no one else will touch the `next` pointer.
+            let cs = unsafe { CriticalSection::new() };
+            next = task.header().run_queue_item.next.borrow(cs).get();
+
+            on_task(task);
+        }
+    }
+}

embassy-executor/src/raw/state_atomics.rs

@@ -0,0 +1,73 @@
+use core::sync::atomic::{AtomicU32, Ordering};
+
+/// Task is spawned (has a future)
+pub(crate) const STATE_SPAWNED: u32 = 1 << 0;
+/// Task is in the executor run queue
+pub(crate) const STATE_RUN_QUEUED: u32 = 1 << 1;
+/// Task is in the executor timer queue
+#[cfg(feature = "integrated-timers")]
+pub(crate) const STATE_TIMER_QUEUED: u32 = 1 << 2;
+
+pub(crate) struct State {
+    state: AtomicU32,
+}
+
+impl State {
+    pub const fn new() -> State {
+        Self {
+            state: AtomicU32::new(0),
+        }
+    }
+
+    /// If task is idle, mark it as spawned + run_queued and return true.
+    #[inline(always)]
+    pub fn spawn(&self) -> bool {
+        self.state
+            .compare_exchange(0, STATE_SPAWNED | STATE_RUN_QUEUED, Ordering::AcqRel, Ordering::Acquire)
+            .is_ok()
+    }
+
+    /// Unmark the task as spawned.
+    #[inline(always)]
+    pub fn despawn(&self) {
+        self.state.fetch_and(!STATE_SPAWNED, Ordering::AcqRel);
+    }
+
+    /// Mark the task as run-queued if it's spawned and isn't already run-queued. Return true on success.
+    #[inline(always)]
+    pub fn run_enqueue(&self) -> bool {
+        self.state
+            .fetch_update(Ordering::SeqCst, Ordering::SeqCst, |state| {
+                // If already scheduled, or if not started,
+                if (state & STATE_RUN_QUEUED != 0) || (state & STATE_SPAWNED == 0) {
+                    None
+                } else {
+                    // Mark it as scheduled
+                    Some(state | STATE_RUN_QUEUED)
+                }
+            })
+            .is_ok()
+    }
+
+    /// Unmark the task as run-queued. Return whether the task is spawned.
+    #[inline(always)]
+    pub fn run_dequeue(&self) -> bool {
+        let state = self.state.fetch_and(!STATE_RUN_QUEUED, Ordering::AcqRel);
+        state & STATE_SPAWNED != 0
+    }
+
+    /// Mark the task as timer-queued. Return whether it was newly queued (i.e. not queued before)
+    #[cfg(feature = "integrated-timers")]
+    #[inline(always)]
+    pub fn timer_enqueue(&self) -> bool {
+        let old_state = self.state.fetch_or(STATE_TIMER_QUEUED, Ordering::AcqRel);
+        old_state & STATE_TIMER_QUEUED == 0
+    }
+
+    /// Unmark the task as timer-queued.
+    #[cfg(feature = "integrated-timers")]
+    #[inline(always)]
+    pub fn timer_dequeue(&self) {
+        self.state.fetch_and(!STATE_TIMER_QUEUED, Ordering::AcqRel);
+    }
+}

embassy-executor/src/raw/state_atomics_arm.rs

@@ -0,0 +1,103 @@
+use core::arch::asm;
+use core::sync::atomic::{compiler_fence, AtomicBool, AtomicU32, Ordering};
+
+// Must be kept in sync with the layout of `State`!
+pub(crate) const STATE_SPAWNED: u32 = 1 << 0;
+pub(crate) const STATE_RUN_QUEUED: u32 = 1 << 8;
+
+#[repr(C, align(4))]
+pub(crate) struct State {
+    /// Task is spawned (has a future)
+    spawned: AtomicBool,
+    /// Task is in the executor run queue
+    run_queued: AtomicBool,
+    /// Task is in the executor timer queue
+    timer_queued: AtomicBool,
+    pad: AtomicBool,
+}
+
+impl State {
+    pub const fn new() -> State {
+        Self {
+            spawned: AtomicBool::new(false),
+            run_queued: AtomicBool::new(false),
+            timer_queued: AtomicBool::new(false),
+            pad: AtomicBool::new(false),
+        }
+    }
+
+    fn as_u32(&self) -> &AtomicU32 {
+        unsafe { &*(self as *const _ as *const AtomicU32) }
+    }
+
+    /// If task is idle, mark it as spawned + run_queued and return true.
+    #[inline(always)]
+    pub fn spawn(&self) -> bool {
+        compiler_fence(Ordering::Release);
+        let r = self
+            .as_u32()
+            .compare_exchange(
+                0,
+                STATE_SPAWNED | STATE_RUN_QUEUED,
+                Ordering::Relaxed,
+                Ordering::Relaxed,
+            )
+            .is_ok();
+        compiler_fence(Ordering::Acquire);
+        r
+    }
+
+    /// Unmark the task as spawned.
+    #[inline(always)]
+    pub fn despawn(&self) {
+        compiler_fence(Ordering::Release);
+        self.spawned.store(false, Ordering::Relaxed);
+    }
+
+    /// Mark the task as run-queued if it's spawned and isn't already run-queued. Return true on success.
+    #[inline(always)]
+    pub fn run_enqueue(&self) -> bool {
+        unsafe {
+            loop {
+                let state: u32;
+                asm!("ldrex {}, [{}]", out(reg) state, in(reg) self, options(nostack));
+
+                if (state & STATE_RUN_QUEUED != 0) || (state & STATE_SPAWNED == 0) {
+                    asm!("clrex", options(nomem, nostack));
+                    return false;
+                }
+
+                let outcome: usize;
+                let new_state = state | STATE_RUN_QUEUED;
+                asm!("strex {}, {}, [{}]", out(reg) outcome, in(reg) new_state, in(reg) self, options(nostack));
+                if outcome == 0 {
+                    return true;
+                }
+            }
+        }
+    }
+
+    /// Unmark the task as run-queued. Return whether the task is spawned.
+    #[inline(always)]
+    pub fn run_dequeue(&self) -> bool {
+        compiler_fence(Ordering::Release);
+
+        let r = self.spawned.load(Ordering::Relaxed);
+        self.run_queued.store(false, Ordering::Relaxed);
+        r
+    }
+
+    /// Mark the task as timer-queued. Return whether it was newly queued (i.e. not queued before)
+    #[cfg(feature = "integrated-timers")]
+    #[inline(always)]
+    pub fn timer_enqueue(&self) -> bool {
+        !self.timer_queued.swap(true, Ordering::Relaxed)
+    }
+
+    /// Unmark the task as timer-queued.
+    #[cfg(feature = "integrated-timers")]
+    #[inline(always)]
+    pub fn timer_dequeue(&self) {
+        self.timer_queued.store(false, Ordering::Relaxed);
+    }
+}

embassy-executor/src/raw/state_critical_section.rs

@@ -0,0 +1,93 @@
+use core::cell::Cell;
+
+use critical_section::Mutex;
+
+/// Task is spawned (has a future)
+pub(crate) const STATE_SPAWNED: u32 = 1 << 0;
+/// Task is in the executor run queue
+pub(crate) const STATE_RUN_QUEUED: u32 = 1 << 1;
+/// Task is in the executor timer queue
+#[cfg(feature = "integrated-timers")]
+pub(crate) const STATE_TIMER_QUEUED: u32 = 1 << 2;
+
+pub(crate) struct State {
+    state: Mutex<Cell<u32>>,
+}
+
+impl State {
+    pub const fn new() -> State {
+        Self {
+            state: Mutex::new(Cell::new(0)),
+        }
+    }
+
+    fn update<R>(&self, f: impl FnOnce(&mut u32) -> R) -> R {
+        critical_section::with(|cs| {
+            let s = self.state.borrow(cs);
+            let mut val = s.get();
+            let r = f(&mut val);
+            s.set(val);
+            r
+        })
+    }
+
+    /// If task is idle, mark it as spawned + run_queued and return true.
+    #[inline(always)]
+    pub fn spawn(&self) -> bool {
+        self.update(|s| {
+            if *s == 0 {
+                *s = STATE_SPAWNED | STATE_RUN_QUEUED;
+                true
+            } else {
+                false
+            }
+        })
+    }
+
+    /// Unmark the task as spawned.
+    #[inline(always)]
+    pub fn despawn(&self) {
+        self.update(|s| *s &= !STATE_SPAWNED);
+    }
+
+    /// Mark the task as run-queued if it's spawned and isn't already run-queued. Return true on success.
+    #[inline(always)]
+    pub fn run_enqueue(&self) -> bool {
+        self.update(|s| {
+            if (*s & STATE_RUN_QUEUED != 0) || (*s & STATE_SPAWNED == 0) {
+                false
+            } else {
+                *s |= STATE_RUN_QUEUED;
+                true
+            }
+        })
+    }
+
+    /// Unmark the task as run-queued. Return whether the task is spawned.
+    #[inline(always)]
+    pub fn run_dequeue(&self) -> bool {
+        self.update(|s| {
+            let ok = *s & STATE_SPAWNED != 0;
+            *s &= !STATE_RUN_QUEUED;
+            ok
+        })
+    }
+
+    /// Mark the task as timer-queued. Return whether it was newly queued (i.e. not queued before)
+    #[cfg(feature = "integrated-timers")]
+    #[inline(always)]
+    pub fn timer_enqueue(&self) -> bool {
+        self.update(|s| {
+            let ok = *s & STATE_TIMER_QUEUED == 0;
+            *s |= STATE_TIMER_QUEUED;
+            ok
+        })
+    }
+
+    /// Unmark the task as timer-queued.
+    #[cfg(feature = "integrated-timers")]
+    #[inline(always)]
+    pub fn timer_dequeue(&self) {
+        self.update(|s| *s &= !STATE_TIMER_QUEUED);
+    }
+}

embassy-executor/src/raw/timer_queue.rs

@@ -1,9 +1,8 @@
 use core::cmp::min;
 
-use atomic_polyfill::Ordering;
 use embassy_time::Instant;
 
-use super::{TaskRef, STATE_TIMER_QUEUED};
+use super::TaskRef;
 use crate::raw::util::SyncUnsafeCell;
 
 pub(crate) struct TimerQueueItem {
@@ -32,10 +31,7 @@ impl TimerQueue {
     pub(crate) unsafe fn update(&self, p: TaskRef) {
         let task = p.header();
         if task.expires_at.get() != Instant::MAX {
-            let old_state = task.state.fetch_or(STATE_TIMER_QUEUED, Ordering::AcqRel);
-            let is_new = old_state & STATE_TIMER_QUEUED == 0;
-
-            if is_new {
+            if task.state.timer_enqueue() {
                 task.timer_queue_item.next.set(self.head.get());
                 self.head.set(Some(p));
             }
@@ -75,7 +71,7 @@ impl TimerQueue {
             } else {
                 // Remove it
                 prev.set(task.timer_queue_item.next.get());
-                task.state.fetch_and(!STATE_TIMER_QUEUED, Ordering::AcqRel);
+                task.state.timer_dequeue();
             }
         }
     }

embassy-executor/src/raw/waker.rs

@@ -3,7 +3,7 @@ use core::task::{RawWaker, RawWakerVTable, Waker};
 
 use super::{wake_task, TaskHeader, TaskRef};
 
-const VTABLE: RawWakerVTable = RawWakerVTable::new(clone, wake, wake, drop);
+static VTABLE: RawWakerVTable = RawWakerVTable::new(clone, wake, wake, drop);
 
 unsafe fn clone(p: *const ()) -> RawWaker {
     RawWaker::new(p, &VTABLE)

embassy-futures/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "embassy-futures"
-version = "0.1.0"
+version = "0.1.1"
 edition = "2021"
 description = "no-std, no-alloc utilities for working with futures"
 repository = "https://github.com/embassy-rs/embassy"

embassy-lora/Cargo.toml

@@ -21,7 +21,7 @@ defmt = { version = "0.3", optional = true }
 log = { version = "0.4.14", optional = true }
 
 embassy-time = { version = "0.1.5", path = "../embassy-time", optional = true }
-embassy-sync = { version = "0.3.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../embassy-sync" }
 embassy-stm32 = { version = "0.1.0", path = "../embassy-stm32", default-features = false, optional = true }
 embedded-hal-async = { version = "=1.0.0-rc.1" }
 embedded-hal = { version = "0.2", features = ["unproven"] }

embassy-lora/src/lib.rs

@@ -1,5 +1,6 @@
 #![no_std]
-#![feature(async_fn_in_trait)]
+#![feature(async_fn_in_trait, impl_trait_projections)]
+#![allow(stable_features, unknown_lints, async_fn_in_trait)]
 //! embassy-lora holds LoRa-specific functionality.
 
 pub(crate) mod fmt;

embassy-macros/src/macros/main.rs

@@ -53,8 +53,7 @@ pub fn wasm() -> TokenStream {
     quote! {
         #[wasm_bindgen::prelude::wasm_bindgen(start)]
         pub fn main() -> Result<(), wasm_bindgen::JsValue> {
-            static EXECUTOR: ::embassy_executor::_export::StaticCell<::embassy_executor::Executor> = ::embassy_executor::_export::StaticCell::new();
-            let executor = EXECUTOR.init(::embassy_executor::Executor::new());
+            let executor = ::std::boxed::Box::leak(::std::boxed::Box::new(::embassy_executor::Executor::new()));
 
             executor.start(|spawner| {
                 spawner.spawn(__embassy_main(spawner)).unwrap();

embassy-net-adin1110/Cargo.toml

@@ -10,7 +10,7 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-heapless = "0.7.16"
+heapless = "0.8"
 defmt = { version = "0.3", optional = true }
 log = { version = "0.4", default-features = false, optional = true }
 embedded-hal-1 = { package = "embedded-hal", version = "=1.0.0-rc.1" }
@@ -22,9 +22,7 @@ embassy-futures = { version = "0.1.0", path = "../embassy-futures" }
 bitfield = "0.14.0"
 
 [dev-dependencies]
-# reenable when https://github.com/dbrgn/embedded-hal-mock/pull/86 is merged.
-#embedded-hal-mock = { git = "https://github.com/dbrgn/embedded-hal-mock", branch = "1-alpha", features = ["embedded-hal-async", "eh1"] }] }
-embedded-hal-mock = { git = "https://github.com/newAM/embedded-hal-mock", branch = "eh1-rc.1", features = ["embedded-hal-async", "eh1"] }
+embedded-hal-mock = { version = "=0.10.0-rc.1", features = ["embedded-hal-async", "eh1"] }
 crc = "3.0.1"
 env_logger = "0.10"
 critical-section = { version = "1.1.2", features = ["std"] }

embassy-net-adin1110/src/lib.rs

@@ -1,5 +1,6 @@
 #![deny(clippy::pedantic)]
 #![feature(async_fn_in_trait)]
+#![allow(stable_features, unknown_lints, async_fn_in_trait)]
 #![cfg_attr(not(any(test, feature = "std")), no_std)]
 #![allow(clippy::module_name_repetitions)]
 #![allow(clippy::missing_errors_doc)]

embassy-net-driver-channel/Cargo.toml

@@ -24,6 +24,6 @@ features = ["defmt"]
 defmt = { version = "0.3", optional = true }
 log = { version = "0.4.14", optional = true }
 
-embassy-sync = { version = "0.3.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../embassy-sync" }
 embassy-futures = { version = "0.1.0", path = "../embassy-futures" }
 embassy-net-driver = { version = "0.2.0", path = "../embassy-net-driver" }

embassy-net-esp-hosted/Cargo.toml

@@ -8,16 +8,16 @@ defmt = { version = "0.3", optional = true }
 log = { version = "0.4.14", optional = true }
 
 embassy-time = { version = "0.1.5", path = "../embassy-time" }
-embassy-sync = { version = "0.3.0", path = "../embassy-sync"}
+embassy-sync = { version = "0.4.0", path = "../embassy-sync"}
 embassy-futures = { version = "0.1.0", path = "../embassy-futures"}
 embassy-net-driver-channel = { version = "0.2.0", path = "../embassy-net-driver-channel"}
 
 embedded-hal = { version = "1.0.0-rc.1" }
 embedded-hal-async = { version = "=1.0.0-rc.1" }
 
-noproto = { git="https://github.com/embassy-rs/noproto", default-features = false, features = ["derive"] }
+noproto = { git="https://github.com/embassy-rs/noproto", rev = "f5e6d1f325b6ad4e344f60452b09576e24671f62", default-features = false, features = ["derive"] }
 #noproto = { version = "0.1", path = "/home/dirbaio/noproto", default-features = false, features = ["derive"] }
-heapless = "0.7.16"
+heapless = "0.8"
 
 [package.metadata.embassy_docs]
 src_base = "https://github.com/embassy-rs/embassy/blob/embassy-net-esp-hosted-v$VERSION/embassy-net-esp-hosted/src/"

embassy-net-esp-hosted/src/control.rs

@@ -97,8 +97,8 @@ impl<'a> Control<'a> {
 
     pub async fn connect(&mut self, ssid: &str, password: &str) -> Result<(), Error> {
         let req = proto::CtrlMsgReqConnectAp {
-            ssid: String::from(ssid),
-            pwd: String::from(password),
+            ssid: unwrap!(String::try_from(ssid)),
+            pwd: unwrap!(String::try_from(password)),
             bssid: String::new(),
             listen_interval: 3,
             is_wpa3_supported: false,

embassy-net-ppp/Cargo.toml

@@ -19,7 +19,7 @@ embedded-io-async = { version = "0.6.0" }
 embassy-net-driver-channel = { version = "0.2.0", path = "../embassy-net-driver-channel" }
 embassy-futures = { version = "0.1.0", path = "../embassy-futures" }
 ppproto = { version = "0.1.2"}
-embassy-sync = { version = "0.3.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../embassy-sync" }
 
 [package.metadata.embassy_docs]
 src_base = "https://github.com/embassy-rs/embassy/blob/embassy-net-ppp-v$VERSION/embassy-net-ppp/src/"

embassy-net-wiznet/src/lib.rs

@@ -1,5 +1,6 @@
 #![no_std]
 #![feature(async_fn_in_trait)]
+#![allow(stable_features, unknown_lints, async_fn_in_trait)]
 #![doc = include_str!("../README.md")]
 
 pub mod chip;

embassy-net/CHANGELOG.md

@@ -5,6 +5,17 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## Unreleased
+
+- Avoid never resolving `TcpIo::read` when the output buffer is empty.
+- Update to `smoltcp` git.
+- Forward constants from `smoltcp` in DNS query results so changing DNS result size in `smoltcp` properly propagates.
+
+## 0.2.1 - 2023-10-31
+
+- Re-add impl_trait_projections
+- Fix: Reset DHCP socket when the link up is detected 
+
 ## 0.2.0 - 2023-10-18
 
 - Re-export `smoltcp::wire::IpEndpoint`

embassy-net/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "embassy-net"
-version = "0.2.0"
+version = "0.2.1"
 edition = "2021"
 license = "MIT OR Apache-2.0"
 description = "Async TCP/IP network stack for embedded systems"
@@ -25,7 +25,7 @@ features = ["nightly", "defmt", "tcp", "udp", "dns", "dhcpv4", "proto-ipv6", "me
 default = []
 std = []
 
-defmt = ["dep:defmt", "smoltcp/defmt", "embassy-net-driver/defmt"]
+defmt = ["dep:defmt", "smoltcp/defmt", "embassy-net-driver/defmt", "heapless/defmt-03"]
 
 nightly = ["dep:embedded-io-async", "dep:embedded-nal-async"]
 
@@ -46,21 +46,21 @@ igmp = ["smoltcp/proto-igmp"]
 defmt = { version = "0.3", optional = true }
 log = { version = "0.4.14", optional = true }
 
-smoltcp = { version = "0.10.0", default-features = false, features = [
+smoltcp = { git = "https://github.com/smoltcp-rs/smoltcp.git", rev = "b57e2f9e70e82a13f31d5ea17e55232c11cc2b2d", default-features = false, features = [
   "socket",
   "async",
 ] }
 
 embassy-net-driver = { version = "0.2.0", path = "../embassy-net-driver" }
 embassy-time = { version = "0.1.5", path = "../embassy-time" }
-embassy-sync = { version = "0.3.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../embassy-sync" }
 embedded-io-async = { version = "0.6.0", optional = true }
 
 managed = { version = "0.8.0", default-features = false, features = [ "map" ] }
-heapless = { version = "0.7.5", default-features = false }
+heapless = { version = "0.8", default-features = false }
 as-slice = "0.2.1"
 generic-array = { version = "0.14.4", default-features = false }
 stable_deref_trait = { version = "1.2.0", default-features = false }
 futures = { version = "0.3.17", default-features = false, features = [ "async-await" ] }
 atomic-pool = "1.0"
-embedded-nal-async = { version = "0.6.0", optional = true }
+embedded-nal-async = { version = "0.7", optional = true }

embassy-net/README.md

@@ -4,7 +4,7 @@
 
 It builds on [`smoltcp`](https://github.com/smoltcp-rs/smoltcp). It provides a higher-level and more opinionated
 API. It glues together the components provided by `smoltcp`, handling the low-level details with defaults and
-memory management designed to work well for embedded systems, aiiming for a more "Just Works" experience.
+memory management designed to work well for embedded systems, aiming for a more "Just Works" experience.
 
 ## Features
 

embassy-net/src/dns.rs

@@ -63,7 +63,11 @@ where
     }
 
     /// Make a query for a given name and return the corresponding IP addresses.
-    pub async fn query(&self, name: &str, qtype: DnsQueryType) -> Result<Vec<IpAddress, 1>, Error> {
+    pub async fn query(
+        &self,
+        name: &str,
+        qtype: DnsQueryType,
+    ) -> Result<Vec<IpAddress, { smoltcp::config::DNS_MAX_RESULT_COUNT }>, Error> {
         self.stack.dns_query(name, qtype).await
     }
 }
@@ -101,7 +105,8 @@ where
     async fn get_host_by_address(
         &self,
         _addr: embedded_nal_async::IpAddr,
-    ) -> Result<heapless::String<256>, Self::Error> {
+        _result: &mut [u8],
+    ) -> Result<usize, Self::Error> {
         todo!()
     }
 }

embassy-net/src/lib.rs

@@ -1,5 +1,6 @@
 #![cfg_attr(not(feature = "std"), no_std)]
-#![cfg_attr(feature = "nightly", feature(async_fn_in_trait))]
+#![cfg_attr(feature = "nightly", feature(async_fn_in_trait, impl_trait_projections))]
+#![cfg_attr(feature = "nightly", allow(stable_features, unknown_lints, async_fn_in_trait))]
 #![warn(missing_docs)]
 #![doc = include_str!("../README.md")]
 
@@ -493,7 +494,11 @@ impl<D: Driver> Stack<D> {
 
     /// Make a query for a given name and return the corresponding IP addresses.
     #[cfg(feature = "dns")]
-    pub async fn dns_query(&self, name: &str, qtype: dns::DnsQueryType) -> Result<Vec<IpAddress, 1>, dns::Error> {
+    pub async fn dns_query(
+        &self,
+        name: &str,
+        qtype: dns::DnsQueryType,
+    ) -> Result<Vec<IpAddress, { smoltcp::config::DNS_MAX_RESULT_COUNT }>, dns::Error> {
         // For A and AAAA queries we try detect whether `name` is just an IP address
         match qtype {
             #[cfg(feature = "proto-ipv4")]

embassy-net/src/tcp.rs

@@ -390,6 +390,13 @@ impl<'d> TcpIo<'d> {
             // CAUTION: smoltcp semantics around EOF are different to what you'd expect
             // from posix-like IO, so we have to tweak things here.
             self.with_mut(|s, _| match s.recv_slice(buf) {
+                // Reading into empty buffer
+                Ok(0) if buf.is_empty() => {
+                    // embedded_io_async::Read's contract is to not block if buf is empty. While
+                    // this function is not a direct implementor of the trait method, we still don't
+                    // want our future to never resolve.
+                    Poll::Ready(Ok(0))
+                }
                 // No data ready
                 Ok(0) => {
                     s.register_recv_waker(cx.waker());
@@ -611,10 +618,7 @@ pub mod client {
         async fn connect<'a>(
             &'a self,
             remote: embedded_nal_async::SocketAddr,
-        ) -> Result<Self::Connection<'a>, Self::Error>
-        where
-            Self: 'a,
-        {
+        ) -> Result<Self::Connection<'a>, Self::Error> {
             let addr: crate::IpAddress = match remote.ip() {
                 #[cfg(feature = "proto-ipv4")]
                 IpAddr::V4(addr) => crate::IpAddress::Ipv4(crate::Ipv4Address::from_bytes(&addr.octets())),

embassy-nrf/Cargo.toml

@@ -95,7 +95,7 @@ _nrf52832_anomaly_109 = []
 
 [dependencies]
 embassy-time = { version = "0.1.5", path = "../embassy-time", optional = true }
-embassy-sync = { version = "0.3.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../embassy-sync" }
 embassy-hal-internal = {version = "0.1.0", path = "../embassy-hal-internal", features = ["cortex-m", "prio-bits-3"] }
 embassy-embedded-hal = {version = "0.1.0", path = "../embassy-embedded-hal" }
 embassy-usb-driver = {version = "0.1.0", path = "../embassy-usb-driver", optional=true }
@@ -110,7 +110,6 @@ defmt = { version = "0.3", optional = true }
 log = { version = "0.4.14", optional = true }
 cortex-m-rt = ">=0.6.15,<0.8"
 cortex-m = "0.7.6"
-futures = { version = "0.3.17", default-features = false }
 critical-section = "1.1"
 rand_core = "0.6.3"
 fixed = "1.10.0"

embassy-nrf/src/buffered_uarte.rs

@@ -12,7 +12,7 @@ use core::cmp::min;
 use core::future::poll_fn;
 use core::marker::PhantomData;
 use core::slice;
-use core::sync::atomic::{compiler_fence, AtomicU8, AtomicUsize, Ordering};
+use core::sync::atomic::{compiler_fence, AtomicBool, AtomicU8, AtomicUsize, Ordering};
 use core::task::Poll;
 
 use embassy_hal_internal::atomic_ring_buffer::RingBuffer;
@@ -41,7 +41,9 @@ mod sealed {
 
         pub rx_waker: AtomicWaker,
         pub rx_buf: RingBuffer,
-        pub rx_bufs: AtomicU8,
+        pub rx_started: AtomicBool,
+        pub rx_started_count: AtomicU8,
+        pub rx_ended_count: AtomicU8,
         pub rx_ppi_ch: AtomicU8,
     }
 }
@@ -65,7 +67,9 @@ impl State {
 
             rx_waker: AtomicWaker::new(),
             rx_buf: RingBuffer::new(),
-            rx_bufs: AtomicU8::new(0),
+            rx_started: AtomicBool::new(false),
+            rx_started_count: AtomicU8::new(0),
+            rx_ended_count: AtomicU8::new(0),
             rx_ppi_ch: AtomicU8::new(0),
         }
     }
@@ -104,28 +108,20 @@ impl<U: UarteInstance> interrupt::typelevel::Handler<U::Interrupt> for Interrupt
             s.rx_waker.wake();
         }
 
-        // If not RXing, start.
-        if s.rx_bufs.load(Ordering::Relaxed) == 0 {
-            let (ptr, len) = rx.push_buf();
-            if len >= half_len {
-                //trace!("  irq_rx: starting {:?}", half_len);
-                s.rx_bufs.store(1, Ordering::Relaxed);
+        if r.events_endrx.read().bits() != 0 {
+            //trace!("  irq_rx: endrx");
+            r.events_endrx.reset();
 
-                // Set up the DMA read
-                r.rxd.ptr.write(|w| unsafe { w.ptr().bits(ptr as u32) });
-                r.rxd.maxcnt.write(|w| unsafe { w.maxcnt().bits(half_len as _) });
-
-                // Start UARTE Receive transaction
-                r.tasks_startrx.write(|w| unsafe { w.bits(1) });
-                rx.push_done(half_len);
-                r.intenset.write(|w| w.rxstarted().set());
-            }
+            let val = s.rx_ended_count.load(Ordering::Relaxed);
+            s.rx_ended_count.store(val.wrapping_add(1), Ordering::Relaxed);
         }
 
-        if r.events_rxstarted.read().bits() != 0 {
+        if r.events_rxstarted.read().bits() != 0 || !s.rx_started.load(Ordering::Relaxed) {
             //trace!("  irq_rx: rxstarted");
             let (ptr, len) = rx.push_buf();
             if len >= half_len {
+                r.events_rxstarted.reset();
+
                 //trace!("  irq_rx: starting second {:?}", half_len);
 
                 // Set up the DMA read
@@ -134,11 +130,50 @@ impl<U: UarteInstance> interrupt::typelevel::Handler<U::Interrupt> for Interrupt
 
                 let chn = s.rx_ppi_ch.load(Ordering::Relaxed);
 
+                // Enable endrx -> startrx PPI channel.
+                // From this point on, if endrx happens, startrx is automatically fired.
                 ppi::regs().chenset.write(|w| unsafe { w.bits(1 << chn) });
 
+                // It is possible that endrx happened BEFORE enabling the PPI. In this case
+                // the PPI channel doesn't trigger, and we'd hang. We have to detect this
+                // and manually start.
+
+                // check again in case endrx has happened between the last check and now.
+                if r.events_endrx.read().bits() != 0 {
+                    //trace!("  irq_rx: endrx");
+                    r.events_endrx.reset();
+
+                    let val = s.rx_ended_count.load(Ordering::Relaxed);
+                    s.rx_ended_count.store(val.wrapping_add(1), Ordering::Relaxed);
+                }
+
+                let rx_ended = s.rx_ended_count.load(Ordering::Relaxed);
+                let rx_started = s.rx_started_count.load(Ordering::Relaxed);
+
+                // If we started the same amount of transfers as ended, the last rxend has
+                // already occured.
+                let rxend_happened = rx_started == rx_ended;
+
+                // Check if the PPI channel is still enabled. The PPI channel disables itself
+                // when it fires, so if it's still enabled it hasn't fired.
+                let ppi_ch_enabled = ppi::regs().chen.read().bits() & (1 << chn) != 0;
+
+                // if rxend happened, and the ppi channel hasn't fired yet, the rxend got missed.
+                // this condition also naturally matches if `!started`, needed to kickstart the DMA.
+                if rxend_happened && ppi_ch_enabled {
+                    //trace!("manually starting.");
+
+                    // disable the ppi ch, it's of no use anymore.
+                    ppi::regs().chenclr.write(|w| unsafe { w.bits(1 << chn) });
+
+                    // manually start
+                    r.tasks_startrx.write(|w| unsafe { w.bits(1) });
+                }
+
                 rx.push_done(half_len);
 
-                r.events_rxstarted.reset();
+                s.rx_started_count.store(rx_started.wrapping_add(1), Ordering::Relaxed);
+                s.rx_started.store(true, Ordering::Relaxed);
             } else {
                 //trace!("  irq_rx: rxstarted no buf");
                 r.intenclr.write(|w| w.rxstarted().clear());
@@ -282,6 +317,8 @@ impl<'d, U: UarteInstance, T: TimerInstance> BufferedUarte<'d, U, T> {
 
         let r = U::regs();
 
+        let hwfc = cts.is_some();
+
         rxd.conf().write(|w| w.input().connect().drive().h0h1());
         r.psel.rxd.write(|w| unsafe { w.bits(rxd.psel_bits()) });
 
@@ -303,7 +340,8 @@ impl<'d, U: UarteInstance, T: TimerInstance> BufferedUarte<'d, U, T> {
         // Initialize state
         let s = U::buffered_state();
         s.tx_count.store(0, Ordering::Relaxed);
-        s.rx_bufs.store(0, Ordering::Relaxed);
+        s.rx_started_count.store(0, Ordering::Relaxed);
+        s.rx_ended_count.store(0, Ordering::Relaxed);
         let len = tx_buffer.len();
         unsafe { s.tx_buf.init(tx_buffer.as_mut_ptr(), len) };
         let len = rx_buffer.len();
@@ -311,7 +349,7 @@ impl<'d, U: UarteInstance, T: TimerInstance> BufferedUarte<'d, U, T> {
 
         // Configure
         r.config.write(|w| {
-            w.hwfc().bit(false);
+            w.hwfc().bit(hwfc);
             w.parity().variant(config.parity);
             w
         });
@@ -333,6 +371,7 @@ impl<'d, U: UarteInstance, T: TimerInstance> BufferedUarte<'d, U, T> {
             w.endtx().set();
             w.rxstarted().set();
             w.error().set();
+            w.endrx().set();
             w
         });
 

embassy-nrf/src/lib.rs

@@ -1,5 +1,6 @@
 #![no_std]
-#![cfg_attr(feature = "nightly", feature(async_fn_in_trait))]
+#![cfg_attr(feature = "nightly", feature(async_fn_in_trait, impl_trait_projections))]
+#![cfg_attr(feature = "nightly", allow(stable_features, unknown_lints, async_fn_in_trait))]
 #![doc = include_str!("../README.md")]
 #![warn(missing_docs)]
 

embassy-nrf/src/pdm.rs

@@ -2,6 +2,7 @@
 
 #![macro_use]
 
+use core::future::poll_fn;
 use core::marker::PhantomData;
 use core::sync::atomic::{compiler_fence, Ordering};
 use core::task::Poll;
@@ -9,7 +10,6 @@ use core::task::Poll;
 use embassy_hal_internal::drop::OnDrop;
 use embassy_hal_internal::{into_ref, PeripheralRef};
 use fixed::types::I7F1;
-use futures::future::poll_fn;
 
 use crate::chip::EASY_DMA_SIZE;
 use crate::gpio::sealed::Pin;

embassy-rp/Cargo.toml

@@ -59,7 +59,7 @@ nightly = ["embedded-hal-1", "embedded-hal-async", "embedded-storage-async", "em
 unstable-traits = ["embedded-hal-1", "embedded-hal-nb"]
 
 [dependencies]
-embassy-sync = { version = "0.3.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../embassy-sync" }
 embassy-time = { version = "0.1.5", path = "../embassy-time", features = [ "tick-hz-1_000_000" ] }
 embassy-futures = { version = "0.1.0", path = "../embassy-futures" }
 embassy-hal-internal = {version = "0.1.0", path = "../embassy-hal-internal", features = ["cortex-m", "prio-bits-2"] }
@@ -94,5 +94,5 @@ pio = {version= "0.2.1" }
 rp2040-boot2 = "0.3"
 
 [dev-dependencies]
-embassy-executor = { version = "0.3.0", path = "../embassy-executor", features = ["nightly", "arch-std", "executor-thread"] }
-static_cell = "1.1"
+embassy-executor = { version = "0.3.3", path = "../embassy-executor", features = ["nightly", "arch-std", "executor-thread"] }
+static_cell = { version = "2" }

embassy-rp/src/lib.rs

@@ -1,5 +1,6 @@
 #![no_std]
-#![cfg_attr(feature = "nightly", feature(async_fn_in_trait))]
+#![cfg_attr(feature = "nightly", feature(async_fn_in_trait, impl_trait_projections))]
+#![cfg_attr(feature = "nightly", allow(stable_features, unknown_lints, async_fn_in_trait))]
 
 // This mod MUST go first, so that the others see its macros.
 pub(crate) mod fmt;

embassy-stm32-wpan/Cargo.toml

@@ -12,7 +12,7 @@ features = ["stm32wb55rg"]
 
 [dependencies]
 embassy-stm32 = { version = "0.1.0", path = "../embassy-stm32" }
-embassy-sync = { version = "0.3.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../embassy-sync" }
 embassy-time = { version = "0.1.5", path = "../embassy-time", optional = true }
 embassy-futures = { version = "0.1.0", path = "../embassy-futures" }
 embassy-hal-internal = { version = "0.1.0", path = "../embassy-hal-internal" }
@@ -21,7 +21,7 @@ embassy-net-driver = { version = "0.2.0", path = "../embassy-net-driver", option
 
 defmt = { version = "0.3", optional = true }
 cortex-m = "0.7.6"
-heapless = "0.7.16"
+heapless = "0.8"
 aligned = "0.4.1"
 
 bit_field = "0.10.2"

embassy-stm32-wpan/src/lib.rs

@@ -1,5 +1,9 @@
 #![no_std]
 #![cfg_attr(any(feature = "ble", feature = "mac"), feature(async_fn_in_trait))]
+#![cfg_attr(
+    any(feature = "ble", feature = "mac"),
+    allow(stable_features, unknown_lints, async_fn_in_trait)
+)]
 #![cfg_attr(feature = "mac", feature(type_alias_impl_trait, concat_bytes))]
 
 // This must go FIRST so that all the other modules see its macros.

embassy-stm32-wpan/src/mac/driver.rs

@@ -1,4 +1,3 @@
-#![allow(incomplete_features)]
 #![deny(unused_must_use)]
 
 use core::task::Context;

embassy-stm32/Cargo.toml

@@ -18,7 +18,7 @@ flavors = [
     { regex_feature = "stm32f7.*", target = "thumbv7em-none-eabi" },
     { regex_feature = "stm32c0.*", target = "thumbv6m-none-eabi" },
     { regex_feature = "stm32g0.*", target = "thumbv6m-none-eabi" },
-    { regex_feature = "stm32g4.*", target = "thumbv7em-none-eabi" },
+    { regex_feature = "stm32g4.*", target = "thumbv7em-none-eabi", features = ["low-power"] },
     { regex_feature = "stm32h5.*", target = "thumbv8m.main-none-eabihf" },
     { regex_feature = "stm32h7.*", target = "thumbv7em-none-eabi" },
     { regex_feature = "stm32l0.*", target = "thumbv6m-none-eabi", features = ["low-power"] },
@@ -32,14 +32,14 @@ flavors = [
 ]
 
 [dependencies]
-embassy-sync = { version = "0.3.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../embassy-sync" }
 embassy-time = { version = "0.1.5", path = "../embassy-time", optional = true }
 embassy-futures = { version = "0.1.0", path = "../embassy-futures" }
 embassy-hal-internal = {version = "0.1.0", path = "../embassy-hal-internal", features = ["cortex-m", "prio-bits-4"] }
 embassy-embedded-hal = {version = "0.1.0", path = "../embassy-embedded-hal" }
 embassy-net-driver = { version = "0.2.0", path = "../embassy-net-driver" }
 embassy-usb-driver = {version = "0.1.0", path = "../embassy-usb-driver", optional = true }
-embassy-executor = { version = "0.3.0", path = "../embassy-executor", optional = true }
+embassy-executor = { version = "0.3.3", path = "../embassy-executor", optional = true }
 
 embedded-hal-02 = { package = "embedded-hal", version = "0.2.6", features = ["unproven"] }
 embedded-hal-1 = { package = "embedded-hal", version = "=1.0.0-rc.1", optional = true}
@@ -58,7 +58,7 @@ rand_core = "0.6.3"
 sdio-host = "0.5.0"
 embedded-sdmmc = { git = "https://github.com/embassy-rs/embedded-sdmmc-rs", rev = "a4f293d3a6f72158385f79c98634cb8a14d0d2fc", optional = true }
 critical-section = "1.1"
-stm32-metapac = { git = "https://github.com/embassy-rs/stm32-data-generated", tag = "stm32-data-bcc9b6bf9fa195e91625849efc4ba473d9ace4e9" }
+stm32-metapac = { git = "https://github.com/embassy-rs/stm32-data-generated", tag = "stm32-data-fbb8f77326dd066aa6c0d66b3b46e76a569dda8b" }
 vcell = "0.1.3"
 bxcan = "0.7.0"
 nb = "1.0.0"
@@ -76,7 +76,7 @@ critical-section = { version = "1.1", features = ["std"] }
 [build-dependencies]
 proc-macro2 = "1.0.36"
 quote = "1.0.15"
-stm32-metapac = { git = "https://github.com/embassy-rs/stm32-data-generated", tag = "stm32-data-bcc9b6bf9fa195e91625849efc4ba473d9ace4e9", default-features = false, features = ["metadata"]}
+stm32-metapac = { git = "https://github.com/embassy-rs/stm32-data-generated", tag = "stm32-data-fbb8f77326dd066aa6c0d66b3b46e76a569dda8b", default-features = false, features = ["metadata"]}
 
 
 [features]
@@ -90,6 +90,7 @@ defmt = ["dep:defmt", "bxcan/unstable-defmt", "embassy-sync/defmt", "embassy-emb
 
 exti = []
 low-power = [ "dep:embassy-executor", "embassy-executor/arch-cortex-m" ]
+low-power-debug-with-sleep = []
 embassy-executor = []
 
 ## Automatically generate `memory.x` file using [`stm32-metapac`](https://docs.rs/stm32-metapac/)

embassy-stm32/build.rs

@@ -6,7 +6,7 @@ use std::{env, fs};
 use proc_macro2::{Ident, TokenStream};
 use quote::{format_ident, quote};
 use stm32_metapac::metadata::ir::{BlockItemInner, Enum, FieldSet};
-use stm32_metapac::metadata::{MemoryRegionKind, PeripheralRccRegister, METADATA};
+use stm32_metapac::metadata::{MemoryRegionKind, PeripheralRccRegister, StopMode, METADATA};
 
 fn main() {
     let target = env::var("TARGET").unwrap();
@@ -556,6 +556,31 @@ fn main() {
                 },
             };
 
+            /*
+                A refcount leak can result if the same field is shared by peripherals with different stop modes
+
+                This condition should be checked in stm32-data
+            */
+            let stop_refcount = match rcc.stop_mode {
+                StopMode::Standby => None,
+                StopMode::Stop2 => Some(quote! { REFCOUNT_STOP2 }),
+                StopMode::Stop1 => Some(quote! { REFCOUNT_STOP1 }),
+            };
+
+            let (incr_stop_refcount, decr_stop_refcount) = match stop_refcount {
+                Some(stop_refcount) => (
+                    quote! {
+                        #[cfg(feature = "low-power")]
+                        unsafe { crate::rcc::#stop_refcount += 1 };
+                    },
+                    quote! {
+                        #[cfg(feature = "low-power")]
+                        unsafe { crate::rcc::#stop_refcount -= 1 };
+                    },
+                ),
+                None => (TokenStream::new(), TokenStream::new()),
+            };
+
             g.extend(quote! {
                 impl crate::rcc::sealed::RccPeripheral for peripherals::#pname {
                     fn frequency() -> crate::time::Hertz {
@@ -563,8 +588,7 @@ fn main() {
                     }
                     fn enable_and_reset_with_cs(_cs: critical_section::CriticalSection) {
                         #before_enable
-                        #[cfg(feature = "low-power")]
-                        crate::rcc::clock_refcount_add(_cs);
+                        #incr_stop_refcount
                         crate::pac::RCC.#en_reg().modify(|w| w.#set_en_field(true));
                         #after_enable
                         #rst
@@ -572,8 +596,7 @@ fn main() {
                     fn disable_with_cs(_cs: critical_section::CriticalSection) {
                         #before_disable
                         crate::pac::RCC.#en_reg().modify(|w| w.#set_en_field(false));
-                        #[cfg(feature = "low-power")]
-                        crate::rcc::clock_refcount_sub(_cs);
+                        #decr_stop_refcount
                     }
                 }
 
@@ -804,7 +827,7 @@ fn main() {
         (("fmc", "NCE"), quote!(crate::fmc::NCEPin)),
         (("fmc", "NOE"), quote!(crate::fmc::NOEPin)),
         (("fmc", "NWE"), quote!(crate::fmc::NWEPin)),
-        (("fmc", "Clk"), quote!(crate::fmc::ClkPin)),
+        (("fmc", "CLK"), quote!(crate::fmc::ClkPin)),
         (("fmc", "BA0"), quote!(crate::fmc::BA0Pin)),
         (("fmc", "BA1"), quote!(crate::fmc::BA1Pin)),
         (("timer", "CH1"), quote!(crate::timer::Channel1Pin)),
@@ -920,17 +943,23 @@ fn main() {
                 }
 
                 if regs.kind == "opamp" {
-                    if !pin.signal.starts_with("VP") {
-                        continue;
+                    if pin.signal.starts_with("VP") {
+                        // Impl NonInvertingPin for the VP* signals (VP0, VP1, VP2, etc)
+                        let peri = format_ident!("{}", p.name);
+                        let pin_name = format_ident!("{}", pin.pin);
+                        let ch: u8 = pin.signal.strip_prefix("VP").unwrap().parse().unwrap();
+
+                        g.extend(quote! {
+                            impl_opamp_vp_pin!( #peri, #pin_name, #ch);
+                        })
+                    } else if pin.signal == "VOUT" {
+                        // Impl OutputPin for the VOUT pin
+                        let peri = format_ident!("{}", p.name);
+                        let pin_name = format_ident!("{}", pin.pin);
+                        g.extend(quote! {
+                            impl_opamp_vout_pin!( #peri, #pin_name );
+                        })
                     }
-
-                    let peri = format_ident!("{}", p.name);
-                    let pin_name = format_ident!("{}", pin.pin);
-                    let ch: u8 = pin.signal.strip_prefix("VP").unwrap().parse().unwrap();
-
-                    g.extend(quote! {
-                        impl_opamp_pin!( #peri, #pin_name, #ch);
-                    })
                 }
 
                 // DAC is special

embassy-stm32/src/dma/gpdma.rs

@@ -299,19 +299,15 @@ impl<'a, C: Channel> Transfer<'a, C> {
 
     pub fn request_stop(&mut self) {
         let ch = self.channel.regs().ch(self.channel.num());
-
-        // Disable the channel. Keep the IEs enabled so the irqs still fire.
-        ch.cr().write(|w| {
-            w.set_tcie(true);
-            w.set_useie(true);
-            w.set_dteie(true);
-            w.set_suspie(true);
+        ch.cr().modify(|w| {
+            w.set_susp(true);
         })
     }
 
     pub fn is_running(&mut self) -> bool {
         let ch = self.channel.regs().ch(self.channel.num());
-        !ch.sr().read().tcf()
+        let sr = ch.sr().read();
+        !sr.tcf() && !sr.suspf()
     }
 
     /// Gets the total remaining transfers for the channel

embassy-stm32/src/eth/v2/descriptors.rs

@@ -119,13 +119,11 @@ impl<'a> TDesRing<'a> {
         // "Preceding reads and writes cannot be moved past subsequent writes."
         fence(Ordering::Release);
 
-        self.index = self.index + 1;
-        if self.index == self.descriptors.len() {
-            self.index = 0;
-        }
-
         // signal DMA it can try again.
-        ETH.ethernet_dma().dmactx_dtpr().write(|w| w.0 = 0)
+        // See issue #2129
+        ETH.ethernet_dma().dmactx_dtpr().write(|w| w.0 = &td as *const _ as u32);
+
+        self.index = (self.index + 1) % self.descriptors.len();
     }
 }
 
@@ -237,21 +235,19 @@ impl<'a> RDesRing<'a> {
 
     /// Pop the packet previously returned by `available`.
     pub(crate) fn pop_packet(&mut self) {
-        let descriptor = &mut self.descriptors[self.index];
-        assert!(descriptor.available());
+        let rd = &mut self.descriptors[self.index];
+        assert!(rd.available());
 
-        self.descriptors[self.index].set_ready(self.buffers[self.index].0.as_mut_ptr());
+        rd.set_ready(self.buffers[self.index].0.as_mut_ptr());
 
         // "Preceding reads and writes cannot be moved past subsequent writes."
         fence(Ordering::Release);
 
         // signal DMA it can try again.
-        ETH.ethernet_dma().dmacrx_dtpr().write(|w| w.0 = 0);
+        // See issue #2129
+        ETH.ethernet_dma().dmacrx_dtpr().write(|w| w.0 = &rd as *const _ as u32);
 
         // Increment index.
-        self.index += 1;
-        if self.index == self.descriptors.len() {
-            self.index = 0
-        }
+        self.index = (self.index + 1) % self.descriptors.len();
     }
 }

embassy-stm32/src/exti.rs

@@ -47,6 +47,9 @@ pub unsafe fn on_irq() {
     #[cfg(any(exti_c0, exti_g0, exti_l5, exti_u5, exti_h5, exti_h50))]
     let bits = EXTI.rpr(0).read().0 | EXTI.fpr(0).read().0;
 
+    // We don't handle or change any EXTI lines above 16.
+    let bits = bits & 0x0000FFFF;
+
     // Mask all the channels that fired.
     cpu_regs().imr(0).modify(|w| w.0 &= !bits);
 

embassy-stm32/src/flash/f4.rs

@@ -465,7 +465,7 @@ pub(crate) fn assert_not_corrupted_read(end_address: u32) {
         feature = "stm32f439vg",
         feature = "stm32f439zg",
     ))]
-    if second_bank_read && unsafe { pac::DBGMCU.idcode().read().rev_id() < REVISION_3 && !pa12_is_output_pull_low() } {
+    if second_bank_read && pac::DBGMCU.idcode().read().rev_id() < REVISION_3 && !pa12_is_output_pull_low() {
         panic!("Read corruption for stm32f42xxG and stm32f43xxG in dual bank mode when PA12 is in use for chips below revision 3, see errata 2.2.11");
     }
 }

embassy-stm32/src/fmc.rs

@@ -12,6 +12,37 @@ pub struct Fmc<'d, T: Instance> {
 
 unsafe impl<'d, T> Send for Fmc<'d, T> where T: Instance {}
 
+impl<'d, T> Fmc<'d, T>
+where
+    T: Instance,
+{
+    /// Create a raw FMC instance.
+    ///
+    /// **Note:** This is currently used to provide access to some basic FMC functions
+    /// for manual configuration for memory types that stm32-fmc does not support.
+    pub fn new_raw(_instance: impl Peripheral<P = T> + 'd) -> Self {
+        Self { peri: PhantomData }
+    }
+
+    /// Enable the FMC peripheral and reset it.
+    pub fn enable(&mut self) {
+        T::enable_and_reset();
+    }
+
+    /// Enable the memory controller on applicable chips.
+    pub fn memory_controller_enable(&mut self) {
+        // fmc v1 and v2 does not have the fmcen bit
+        // fsmc v1, v2 and v3 does not have the fmcen bit
+        // This is a "not" because it is expected that all future versions have this bit
+        #[cfg(not(any(fmc_v1x3, fmc_v2x1, fsmc_v1x0, fsmc_v1x3, fsmc_v2x3, fsmc_v3x1)))]
+        T::REGS.bcr1().modify(|r| r.set_fmcen(true));
+    }
+
+    pub fn source_clock_hz(&self) -> u32 {
+        <T as crate::rcc::sealed::RccPeripheral>::frequency().0
+    }
+}
+
 unsafe impl<'d, T> stm32_fmc::FmcPeripheral for Fmc<'d, T>
 where
     T: Instance,

embassy-stm32/src/lib.rs

@@ -1,5 +1,6 @@
 #![cfg_attr(not(test), no_std)]
-#![cfg_attr(feature = "nightly", feature(async_fn_in_trait))]
+#![cfg_attr(feature = "nightly", feature(async_fn_in_trait, impl_trait_projections))]
+#![cfg_attr(feature = "nightly", allow(stable_features, unknown_lints, async_fn_in_trait))]
 
 //! ## Feature flags
 #![doc = document_features::document_features!(feature_label = r#"<span class="stab portability"><code>{feature}</code></span>"#)]
@@ -226,8 +227,9 @@ pub fn init(config: Config) -> Peripherals {
             time_driver::init(cs);
 
             #[cfg(feature = "low-power")]
-            while !crate::rcc::low_power_ready() {
-                crate::rcc::clock_refcount_sub(cs);
+            {
+                crate::rcc::REFCOUNT_STOP2 = 0;
+                crate::rcc::REFCOUNT_STOP1 = 0;
             }
         }
 

embassy-stm32/src/low_power.rs

@@ -1,3 +1,50 @@
+/// The STM32 line of microcontrollers support various deep-sleep modes which exploit clock-gating
+/// to reduce power consumption. `embassy-stm32` provides a low-power executor, [`Executor`] which
+/// can use knowledge of which peripherals are currently blocked upon to transparently and safely
+/// enter such low-power modes (currently, only `STOP2`) when idle.
+///
+/// The executor determines which peripherals are active by their RCC state; consequently,
+/// low-power states can only be entered if all peripherals have been `drop`'d. There are a few
+/// exceptions to this rule:
+///
+///  * `GPIO`
+///  * `RCC`
+///
+/// Since entering and leaving low-power modes typically incurs a significant latency, the
+/// low-power executor will only attempt to enter when the next timer event is at least
+/// [`time_driver::MIN_STOP_PAUSE`] in the future.
+///
+/// Currently there is no macro analogous to `embassy_executor::main` for this executor;
+/// consequently one must define their entrypoint manually. Moveover, you must relinquish control
+/// of the `RTC` peripheral to the executor. This will typically look like
+///
+/// ```rust,no_run
+/// use embassy_executor::Spawner;
+/// use embassy_stm32::low_power::Executor;
+/// use embassy_stm32::rtc::{Rtc, RtcConfig};
+/// use static_cell::make_static;
+///
+/// #[cortex_m_rt::entry]
+/// fn main() -> ! {
+///     Executor::take().run(|spawner| {
+///         unwrap!(spawner.spawn(async_main(spawner)));
+///     });
+/// }
+///
+/// #[embassy_executor::task]
+/// async fn async_main(spawner: Spawner) {
+///     // initialize the platform...
+///     let mut config = embassy_stm32::Config::default();
+///     let p = embassy_stm32::init(config);
+///
+///     // give the RTC to the executor...
+///     let mut rtc = Rtc::new(p.RTC, RtcConfig::default());
+///     let rtc = make_static!(rtc);
+///     embassy_stm32::low_power::stop_with_rtc(rtc);
+///
+///     // your application here...
+/// }
+/// ```
 use core::arch::asm;
 use core::marker::PhantomData;
 use core::sync::atomic::{compiler_fence, Ordering};
@@ -6,7 +53,6 @@ use cortex_m::peripheral::SCB;
 use embassy_executor::*;
 
 use crate::interrupt;
-use crate::rcc::low_power_ready;
 use crate::time_driver::{get_driver, RtcDriver};
 
 const THREAD_PENDER: usize = usize::MAX;
@@ -33,6 +79,21 @@ pub fn stop_with_rtc(rtc: &'static Rtc) {
     unsafe { EXECUTOR.as_mut().unwrap() }.stop_with_rtc(rtc)
 }
 
+pub fn stop_ready(stop_mode: StopMode) -> bool {
+    match unsafe { EXECUTOR.as_mut().unwrap() }.stop_mode() {
+        Some(StopMode::Stop2) => true,
+        Some(StopMode::Stop1) => stop_mode == StopMode::Stop1,
+        None => false,
+    }
+}
+
+#[non_exhaustive]
+#[derive(PartialEq)]
+pub enum StopMode {
+    Stop1,
+    Stop2,
+}
+
 /// Thread mode executor, using WFE/SEV.
 ///
 /// This is the simplest and most common kind of executor. It runs on
@@ -53,7 +114,7 @@ pub struct Executor {
 impl Executor {
     /// Create a new Executor.
     pub fn take() -> &'static mut Self {
-        unsafe {
+        critical_section::with(|_| unsafe {
             assert!(EXECUTOR.is_none());
 
             EXECUTOR = Some(Self {
@@ -64,7 +125,7 @@ impl Executor {
             });
 
             EXECUTOR.as_mut().unwrap()
-        }
+        })
     }
 
     unsafe fn on_wakeup_irq(&mut self) {
@@ -80,17 +141,39 @@ impl Executor {
         trace!("low power: stop with rtc configured");
     }
 
+    fn stop_mode(&self) -> Option<StopMode> {
+        if unsafe { crate::rcc::REFCOUNT_STOP2 == 0 } && unsafe { crate::rcc::REFCOUNT_STOP1 == 0 } {
+            Some(StopMode::Stop2)
+        } else if unsafe { crate::rcc::REFCOUNT_STOP1 == 0 } {
+            Some(StopMode::Stop1)
+        } else {
+            None
+        }
+    }
+
+    fn configure_stop(&mut self, _stop_mode: StopMode) {
+        // TODO: configure chip-specific settings for stop
+    }
+
     fn configure_pwr(&mut self) {
         self.scb.clear_sleepdeep();
 
         compiler_fence(Ordering::SeqCst);
 
-        if !low_power_ready() {
+        let stop_mode = self.stop_mode();
+        if stop_mode.is_none() {
             trace!("low power: not ready to stop");
         } else if self.time_driver.pause_time().is_err() {
             trace!("low power: failed to pause time");
         } else {
-            trace!("low power: stop");
+            let stop_mode = stop_mode.unwrap();
+            match stop_mode {
+                StopMode::Stop1 => trace!("low power: stop 1"),
+                StopMode::Stop2 => trace!("low power: stop 2"),
+            }
+            self.configure_stop(stop_mode);
+
+            #[cfg(not(feature = "low-power-debug-with-sleep"))]
             self.scb.set_sleepdeep();
         }
     }

embassy-stm32/src/opamp.rs

@@ -13,21 +13,50 @@ pub enum OpAmpGain {
     Mul16,
 }
 
-pub struct OpAmpOutput<'d, 'p, T: Instance, P: NonInvertingPin<T>> {
-    _inner: &'d OpAmp<'d, T>,
-    _input: &'p mut P,
+#[derive(Clone, Copy)]
+pub enum OpAmpSpeed {
+    Normal,
+    HighSpeed,
 }
 
+#[cfg(opamp_g4)]
+impl From<OpAmpSpeed> for crate::pac::opamp::vals::OpampCsrOpahsm {
+    fn from(v: OpAmpSpeed) -> Self {
+        match v {
+            OpAmpSpeed::Normal => crate::pac::opamp::vals::OpampCsrOpahsm::NORMAL,
+            OpAmpSpeed::HighSpeed => crate::pac::opamp::vals::OpampCsrOpahsm::HIGHSPEED,
+        }
+    }
+}
+
+/// OpAmp external outputs, wired to a GPIO pad.
+///
+/// The GPIO output pad is held by this struct to ensure it cannot be used elsewhere.
+///
+/// This struct can also be used as an ADC input.
+pub struct OpAmpOutput<'d, 'p, T: Instance, P: OutputPin<T>> {
+    _inner: &'d OpAmp<'d, T>,
+    _output: &'p mut P,
+}
+
+/// OpAmp internal outputs, wired directly to ADC inputs.
+///
+/// This struct can be used as an ADC input.
+pub struct OpAmpInternalOutput<'d, T: Instance> {
+    _inner: &'d OpAmp<'d, T>,
+}
+
+/// OpAmp driver.
 pub struct OpAmp<'d, T: Instance> {
     _inner: PeripheralRef<'d, T>,
 }
 
 impl<'d, T: Instance> OpAmp<'d, T> {
-    pub fn new(opamp: impl Peripheral<P = T> + 'd) -> Self {
-        Self::new_inner(opamp)
-    }
-
-    fn new_inner(opamp: impl Peripheral<P = T> + 'd) -> Self {
+    /// Create a new driver instance.
+    ///
+    /// Enables the OpAmp and configures the speed, but
+    /// does not set any other configuration.
+    pub fn new(opamp: impl Peripheral<P = T> + 'd, #[cfg(opamp_g4)] speed: OpAmpSpeed) -> Self {
         into_ref!(opamp);
 
         #[cfg(opamp_f3)]
@@ -38,15 +67,34 @@ impl<'d, T: Instance> OpAmp<'d, T> {
         #[cfg(opamp_g4)]
         T::regs().opamp_csr().modify(|w| {
             w.set_opaen(true);
+            w.set_opahsm(speed.into());
         });
 
         Self { _inner: opamp }
     }
 
-    pub fn buffer_for<'a, 'b, P>(&'a mut self, pin: &'b mut P, gain: OpAmpGain) -> OpAmpOutput<'a, 'b, T, P>
+    /// Configure the OpAmp as a buffer for the provided input pin,
+    /// outputting to the provided output pin.
+    ///
+    /// The input pin is configured for analogue mode but not consumed,
+    /// so it may subsequently be used for ADC or comparator inputs.
+    ///
+    /// The output pin is held within the returned [`OpAmpOutput`] struct,
+    /// preventing it being used elsewhere. The `OpAmpOutput` can then be
+    /// directly used as an ADC input.
+    pub fn buffer_ext<'a, 'b, IP, OP>(
+        &'a mut self,
+        in_pin: &IP,
+        out_pin: &'b mut OP,
+        gain: OpAmpGain,
+    ) -> OpAmpOutput<'a, 'b, T, OP>
     where
-        P: NonInvertingPin<T>,
+        IP: NonInvertingPin<T> + crate::gpio::sealed::Pin,
+        OP: OutputPin<T> + crate::gpio::sealed::Pin,
     {
+        in_pin.set_as_analog();
+        out_pin.set_as_analog();
+
         let (vm_sel, pga_gain) = match gain {
             OpAmpGain::Mul1 => (0b11, 0b00),
             OpAmpGain::Mul2 => (0b10, 0b00),
@@ -57,25 +105,76 @@ impl<'d, T: Instance> OpAmp<'d, T> {
 
         #[cfg(opamp_f3)]
         T::regs().opampcsr().modify(|w| {
-            w.set_vp_sel(pin.channel());
+            w.set_vp_sel(in_pin.channel());
             w.set_vm_sel(vm_sel);
             w.set_pga_gain(pga_gain);
+            w.set_opampen(true);
         });
 
         #[cfg(opamp_g4)]
         T::regs().opamp_csr().modify(|w| {
             use crate::pac::opamp::vals::*;
 
-            w.set_vp_sel(OpampCsrVpSel::from_bits(pin.channel()));
+            w.set_vp_sel(OpampCsrVpSel::from_bits(in_pin.channel()));
             w.set_vm_sel(OpampCsrVmSel::from_bits(vm_sel));
             w.set_pga_gain(OpampCsrPgaGain::from_bits(pga_gain));
+            w.set_opaintoen(OpampCsrOpaintoen::OUTPUTPIN);
+            w.set_opaen(true);
         });
 
         OpAmpOutput {
             _inner: self,
-            _input: pin,
+            _output: out_pin,
         }
     }
+
+    /// Configure the OpAmp as a buffer for the provided input pin,
+    /// with the output only used internally.
+    ///
+    /// The input pin is configured for analogue mode but not consumed,
+    /// so it may be subsequently used for ADC or comparator inputs.
+    ///
+    /// The returned `OpAmpInternalOutput` struct may be used as an ADC input.
+    #[cfg(opamp_g4)]
+    pub fn buffer_int<'a, P>(&'a mut self, pin: &P, gain: OpAmpGain) -> OpAmpInternalOutput<'a, T>
+    where
+        P: NonInvertingPin<T> + crate::gpio::sealed::Pin,
+    {
+        pin.set_as_analog();
+
+        let (vm_sel, pga_gain) = match gain {
+            OpAmpGain::Mul1 => (0b11, 0b00),
+            OpAmpGain::Mul2 => (0b10, 0b00),
+            OpAmpGain::Mul4 => (0b10, 0b01),
+            OpAmpGain::Mul8 => (0b10, 0b10),
+            OpAmpGain::Mul16 => (0b10, 0b11),
+        };
+
+        T::regs().opamp_csr().modify(|w| {
+            use crate::pac::opamp::vals::*;
+            w.set_vp_sel(OpampCsrVpSel::from_bits(pin.channel()));
+            w.set_vm_sel(OpampCsrVmSel::from_bits(vm_sel));
+            w.set_pga_gain(OpampCsrPgaGain::from_bits(pga_gain));
+            w.set_opaintoen(OpampCsrOpaintoen::ADCCHANNEL);
+            w.set_opaen(true);
+        });
+
+        OpAmpInternalOutput { _inner: self }
+    }
+}
+
+impl<'d, T: Instance> Drop for OpAmp<'d, T> {
+    fn drop(&mut self) {
+        #[cfg(opamp_f3)]
+        T::regs().opampcsr().modify(|w| {
+            w.set_opampen(false);
+        });
+
+        #[cfg(opamp_g4)]
+        T::regs().opamp_csr().modify(|w| {
+            w.set_opaen(false);
+        });
+    }
 }
 
 pub trait Instance: sealed::Instance + 'static {}
@@ -92,18 +191,19 @@ pub(crate) mod sealed {
     pub trait InvertingPin<T: Instance> {
         fn channel(&self) -> u8;
     }
+
+    pub trait OutputPin<T: Instance> {}
 }
 
 pub trait NonInvertingPin<T: Instance>: sealed::NonInvertingPin<T> {}
-
 pub trait InvertingPin<T: Instance>: sealed::InvertingPin<T> {}
+pub trait OutputPin<T: Instance>: sealed::OutputPin<T> {}
 
-#[cfg(opamp_f3)]
-macro_rules! impl_opamp_output {
+macro_rules! impl_opamp_external_output {
     ($inst:ident, $adc:ident, $ch:expr) => {
         foreach_adc!(
             ($adc, $common_inst:ident, $adc_clock:ident) => {
-                impl<'d, 'p, P: NonInvertingPin<crate::peripherals::$inst>> crate::adc::sealed::AdcPin<crate::peripherals::$adc>
+                impl<'d, 'p, P: OutputPin<crate::peripherals::$inst>> crate::adc::sealed::AdcPin<crate::peripherals::$adc>
                     for OpAmpOutput<'d, 'p, crate::peripherals::$inst, P>
                 {
                     fn channel(&self) -> u8 {
@@ -111,7 +211,7 @@ macro_rules! impl_opamp_output {
                     }
                 }
 
-                impl<'d, 'p, P: NonInvertingPin<crate::peripherals::$inst>> crate::adc::AdcPin<crate::peripherals::$adc>
+                impl<'d, 'p, P: OutputPin<crate::peripherals::$inst>> crate::adc::AdcPin<crate::peripherals::$adc>
                     for OpAmpOutput<'d, 'p, crate::peripherals::$inst, P>
                 {
                 }
@@ -120,19 +220,79 @@ macro_rules! impl_opamp_output {
     };
 }
 
-#[cfg(opamp_f3)]
 foreach_peripheral!(
     (opamp, OPAMP1) => {
-        impl_opamp_output!(OPAMP1, ADC1, 3);
+        impl_opamp_external_output!(OPAMP1, ADC1, 3);
     };
     (opamp, OPAMP2) => {
-        impl_opamp_output!(OPAMP2, ADC2, 3);
+        impl_opamp_external_output!(OPAMP2, ADC2, 3);
     };
     (opamp, OPAMP3) => {
-        impl_opamp_output!(OPAMP3, ADC3, 1);
+        impl_opamp_external_output!(OPAMP3, ADC3, 1);
     };
+    // OPAMP4 only in STM32G4 Cat 3 devices
     (opamp, OPAMP4) => {
-        impl_opamp_output!(OPAMP4, ADC4, 3);
+        impl_opamp_external_output!(OPAMP4, ADC4, 3);
+    };
+    // OPAMP5 only in STM32G4 Cat 3 devices
+    (opamp, OPAMP5) => {
+        impl_opamp_external_output!(OPAMP5, ADC5, 1);
+    };
+    // OPAMP6 only in STM32G4 Cat 3/4 devices
+    (opamp, OPAMP6) => {
+        impl_opamp_external_output!(OPAMP6, ADC1, 14);
+    };
+);
+
+#[cfg(opamp_g4)]
+macro_rules! impl_opamp_internal_output {
+    ($inst:ident, $adc:ident, $ch:expr) => {
+        foreach_adc!(
+            ($adc, $common_inst:ident, $adc_clock:ident) => {
+                impl<'d> crate::adc::sealed::AdcPin<crate::peripherals::$adc>
+                    for OpAmpInternalOutput<'d, crate::peripherals::$inst>
+                {
+                    fn channel(&self) -> u8 {
+                        $ch
+                    }
+                }
+
+                impl<'d> crate::adc::AdcPin<crate::peripherals::$adc>
+                    for OpAmpInternalOutput<'d, crate::peripherals::$inst>
+                {
+                }
+            };
+        );
+    };
+}
+
+#[cfg(opamp_g4)]
+foreach_peripheral!(
+    (opamp, OPAMP1) => {
+        impl_opamp_internal_output!(OPAMP1, ADC1, 13);
+    };
+    (opamp, OPAMP2) => {
+        impl_opamp_internal_output!(OPAMP2, ADC2, 16);
+    };
+    (opamp, OPAMP3) => {
+        impl_opamp_internal_output!(OPAMP3, ADC2, 18);
+        // Only in Cat 3/4 devices
+        impl_opamp_internal_output!(OPAMP3, ADC3, 13);
+    };
+    // OPAMP4 only in Cat 3 devices
+    (opamp, OPAMP4) => {
+        impl_opamp_internal_output!(OPAMP4, ADC5, 5);
+    };
+    // OPAMP5 only in Cat 3 devices
+    (opamp, OPAMP5) => {
+        impl_opamp_internal_output!(OPAMP5, ADC5, 3);
+    };
+    // OPAMP6 only in Cat 3/4 devices
+    (opamp, OPAMP6) => {
+        // Only in Cat 3 devices
+        impl_opamp_internal_output!(OPAMP6, ADC4, 17);
+        // Only in Cat 4 devices
+        impl_opamp_internal_output!(OPAMP6, ADC3, 17);
     };
 );
 
@@ -145,13 +305,12 @@ foreach_peripheral! {
         }
 
         impl Instance for crate::peripherals::$inst {
-
         }
     };
 }
 
 #[allow(unused_macros)]
-macro_rules! impl_opamp_pin {
+macro_rules! impl_opamp_vp_pin {
     ($inst:ident, $pin:ident, $ch:expr) => {
         impl crate::opamp::NonInvertingPin<peripherals::$inst> for crate::peripherals::$pin {}
         impl crate::opamp::sealed::NonInvertingPin<peripherals::$inst> for crate::peripherals::$pin {
@@ -161,3 +320,11 @@ macro_rules! impl_opamp_pin {
         }
     };
 }
+
+#[allow(unused_macros)]
+macro_rules! impl_opamp_vout_pin {
+    ($inst:ident, $pin:ident) => {
+        impl crate::opamp::OutputPin<peripherals::$inst> for crate::peripherals::$pin {}
+        impl crate::opamp::sealed::OutputPin<peripherals::$inst> for crate::peripherals::$pin {}
+    };
+}

embassy-stm32/src/rcc/f.rs

@@ -1,7 +1,11 @@
+use stm32_metapac::flash::vals::Latency;
+
 pub use crate::pac::rcc::vals::{
-    Hpre as AHBPrescaler, Pllm as PllPreDiv, Plln as PllMul, Pllp, Pllq, Pllr, Pllsrc as PllSource,
-    Ppre as APBPrescaler, Sw as Sysclk,
+    Hpre as AHBPrescaler, Pllm as PllPreDiv, Plln as PllMul, Pllp as PllPDiv, Pllq as PllQDiv, Pllr as PllRDiv,
+    Pllsrc as PllSource, Ppre as APBPrescaler, Sw as Sysclk,
 };
+#[cfg(any(stm32f4, stm32f7))]
+use crate::pac::PWR;
 use crate::pac::{FLASH, RCC};
 use crate::rcc::{set_freqs, Clocks};
 use crate::time::Hertz;
@@ -48,11 +52,27 @@ pub struct Pll {
     pub mul: PllMul,
 
     /// PLL P division factor. If None, PLL P output is disabled.
-    pub divp: Option<Pllp>,
+    pub divp: Option<PllPDiv>,
     /// PLL Q division factor. If None, PLL Q output is disabled.
-    pub divq: Option<Pllq>,
+    pub divq: Option<PllQDiv>,
     /// PLL R division factor. If None, PLL R output is disabled.
-    pub divr: Option<Pllr>,
+    pub divr: Option<PllRDiv>,
+}
+
+/// Voltage range of the power supply used.
+///
+/// Used to calculate flash waitstates. See
+/// RM0033 - Table 3. Number of wait states according to Cortex®-M3 clock frequency
+#[cfg(stm32f2)]
+pub enum VoltageScale {
+    /// 2.7 to 3.6 V
+    Range0,
+    /// 2.4 to 2.7 V
+    Range1,
+    /// 2.1 to 2.4 V
+    Range2,
+    /// 1.8 to 2.1 V
+    Range3,
 }
 
 /// Configuration of the core clocks
@@ -65,7 +85,7 @@ pub struct Config {
     pub pll_src: PllSource,
 
     pub pll: Option<Pll>,
-    #[cfg(any(all(stm32f4, not(stm32f410)), stm32f7))]
+    #[cfg(any(stm32f2, all(stm32f4, not(stm32f410)), stm32f7))]
     pub plli2s: Option<Pll>,
     #[cfg(any(stm32f446, stm32f427, stm32f437, stm32f4x9, stm32f7))]
     pub pllsai: Option<Pll>,
@@ -75,6 +95,9 @@ pub struct Config {
     pub apb2_pre: APBPrescaler,
 
     pub ls: super::LsConfig,
+
+    #[cfg(stm32f2)]
+    pub voltage: VoltageScale,
 }
 
 impl Default for Config {
@@ -85,7 +108,7 @@ impl Default for Config {
             sys: Sysclk::HSI,
             pll_src: PllSource::HSI,
             pll: None,
-            #[cfg(any(all(stm32f4, not(stm32f410)), stm32f7))]
+            #[cfg(any(stm32f2, all(stm32f4, not(stm32f410)), stm32f7))]
             plli2s: None,
             #[cfg(any(stm32f446, stm32f427, stm32f437, stm32f4x9, stm32f7))]
             pllsai: None,
@@ -95,17 +118,24 @@ impl Default for Config {
             apb2_pre: APBPrescaler::DIV1,
 
             ls: Default::default(),
+
+            #[cfg(stm32f2)]
+            voltage: VoltageScale::Range3,
         }
     }
 }
 
 pub(crate) unsafe fn init(config: Config) {
+    // set VOS to SCALE1, if use PLL
+    // TODO: check real clock speed before set VOS
+    #[cfg(any(stm32f4, stm32f7))]
+    if config.pll.is_some() {
+        PWR.cr1().modify(|w| w.set_vos(crate::pac::pwr::vals::Vos::SCALE1));
+    }
+
     // always enable overdrive for now. Make it configurable in the future.
-    #[cfg(not(any(
-        stm32f401, stm32f410, stm32f411, stm32f412, stm32f413, stm32f423, stm32f405, stm32f407, stm32f415, stm32f417
-    )))]
+    #[cfg(any(stm32f446, stm32f4x9, stm32f427, stm32f437, stm32f7))]
     {
-        use crate::pac::PWR;
         PWR.cr1().modify(|w| w.set_oden(true));
         while !PWR.csr1().read().odrdy() {}
 
@@ -152,9 +182,9 @@ pub(crate) unsafe fn init(config: Config) {
         source: config.pll_src,
     };
     let pll = init_pll(PllInstance::Pll, config.pll, &pll_input);
-    #[cfg(any(all(stm32f4, not(any(stm32f410, stm32f429))), stm32f7))]
+    #[cfg(any(stm32f2, all(stm32f4, not(stm32f410)), stm32f7))]
     let _plli2s = init_pll(PllInstance::Plli2s, config.plli2s, &pll_input);
-    #[cfg(all(any(stm32f446, stm32f427, stm32f437, stm32f4x9, stm32f7), not(stm32f429)))]
+    #[cfg(any(stm32f446, stm32f427, stm32f437, stm32f4x9, stm32f7))]
     let _pllsai = init_pll(PllInstance::Pllsai, config.pllsai, &pll_input);
 
     // Configure sysclk
@@ -176,7 +206,48 @@ pub(crate) unsafe fn init(config: Config) {
 
     let rtc = config.ls.init();
 
-    flash_setup(hclk);
+    #[cfg(stm32f2)]
+    let latency = match (config.voltage, hclk.0) {
+        (VoltageScale::Range3, ..=16_000_000) => Latency::WS0,
+        (VoltageScale::Range3, ..=32_000_000) => Latency::WS1,
+        (VoltageScale::Range3, ..=48_000_000) => Latency::WS2,
+        (VoltageScale::Range3, ..=64_000_000) => Latency::WS3,
+        (VoltageScale::Range3, ..=80_000_000) => Latency::WS4,
+        (VoltageScale::Range3, ..=96_000_000) => Latency::WS5,
+        (VoltageScale::Range3, ..=112_000_000) => Latency::WS6,
+        (VoltageScale::Range3, ..=120_000_000) => Latency::WS7,
+        (VoltageScale::Range2, ..=18_000_000) => Latency::WS0,
+        (VoltageScale::Range2, ..=36_000_000) => Latency::WS1,
+        (VoltageScale::Range2, ..=54_000_000) => Latency::WS2,
+        (VoltageScale::Range2, ..=72_000_000) => Latency::WS3,
+        (VoltageScale::Range2, ..=90_000_000) => Latency::WS4,
+        (VoltageScale::Range2, ..=108_000_000) => Latency::WS5,
+        (VoltageScale::Range2, ..=120_000_000) => Latency::WS6,
+        (VoltageScale::Range1, ..=24_000_000) => Latency::WS0,
+        (VoltageScale::Range1, ..=48_000_000) => Latency::WS1,
+        (VoltageScale::Range1, ..=72_000_000) => Latency::WS2,
+        (VoltageScale::Range1, ..=96_000_000) => Latency::WS3,
+        (VoltageScale::Range1, ..=120_000_000) => Latency::WS4,
+        (VoltageScale::Range0, ..=30_000_000) => Latency::WS0,
+        (VoltageScale::Range0, ..=60_000_000) => Latency::WS1,
+        (VoltageScale::Range0, ..=90_000_000) => Latency::WS2,
+        (VoltageScale::Range0, ..=120_000_000) => Latency::WS3,
+        _ => unreachable!(),
+    };
+
+    #[cfg(any(stm32f4, stm32f7))]
+    let latency = {
+        // Be conservative with voltage ranges
+        const FLASH_LATENCY_STEP: u32 = 30_000_000;
+
+        let latency = (hclk.0 - 1) / FLASH_LATENCY_STEP;
+        debug!("flash: latency={}", latency);
+
+        Latency::from_bits(latency as u8)
+    };
+
+    FLASH.acr().write(|w| w.set_latency(latency));
+    while FLASH.acr().read().latency() != latency {}
 
     RCC.cfgr().modify(|w| {
         w.set_sw(config.sys);
@@ -197,25 +268,15 @@ pub(crate) unsafe fn init(config: Config) {
         pclk2_tim,
         rtc,
         pll1_q: pll.q,
-        #[cfg(all(rcc_f4, not(any(stm32f410, stm32f429))))]
+        #[cfg(all(rcc_f4, not(stm32f410)))]
         plli2s1_q: _plli2s.q,
-        #[cfg(all(rcc_f4, not(any(stm32f410, stm32f429))))]
+        #[cfg(all(rcc_f4, not(stm32f410)))]
         plli2s1_r: _plli2s.r,
 
-        #[cfg(stm32f429)]
-        plli2s1_q: None,
-        #[cfg(stm32f429)]
-        plli2s1_r: None,
-
-        #[cfg(any(stm32f427, stm32f437, stm32f439, stm32f446, stm32f469, stm32f479))]
+        #[cfg(any(stm32f427, stm32f429, stm32f437, stm32f439, stm32f446, stm32f469, stm32f479))]
         pllsai1_q: _pllsai.q,
-        #[cfg(any(stm32f427, stm32f437, stm32f439, stm32f446, stm32f469, stm32f479))]
+        #[cfg(any(stm32f427, stm32f429, stm32f437, stm32f439, stm32f446, stm32f469, stm32f479))]
         pllsai1_r: _pllsai.r,
-
-        #[cfg(stm32f429)]
-        pllsai1_q: None,
-        #[cfg(stm32f429)]
-        pllsai1_r: None,
     });
 }
 
@@ -233,11 +294,10 @@ struct PllOutput {
     r: Option<Hertz>,
 }
 
-#[allow(dead_code)]
 #[derive(PartialEq, Eq, Clone, Copy)]
 enum PllInstance {
     Pll,
-    #[cfg(any(all(stm32f4, not(stm32f410)), stm32f7))]
+    #[cfg(any(stm32f2, all(stm32f4, not(stm32f410)), stm32f7))]
     Plli2s,
     #[cfg(any(stm32f446, stm32f427, stm32f437, stm32f4x9, stm32f7))]
     Pllsai,
@@ -249,7 +309,7 @@ fn pll_enable(instance: PllInstance, enabled: bool) {
             RCC.cr().modify(|w| w.set_pllon(enabled));
             while RCC.cr().read().pllrdy() != enabled {}
         }
-        #[cfg(any(all(stm32f4, not(stm32f410)), stm32f7))]
+        #[cfg(any(stm32f2, all(stm32f4, not(stm32f410)), stm32f7))]
         PllInstance::Plli2s => {
             RCC.cr().modify(|w| w.set_plli2son(enabled));
             while RCC.cr().read().plli2srdy() != enabled {}
@@ -280,6 +340,18 @@ fn init_pll(instance: PllInstance, config: Option<Pll>, input: &PllInput) -> Pll
     let vco_freq = in_freq * pll.mul;
     assert!(max::PLL_VCO.contains(&vco_freq));
 
+    // stm32f2 plls are like swiss cheese
+    #[cfg(stm32f2)]
+    match instance {
+        PllInstance::Pll => {
+            assert!(pll.divr.is_none());
+        }
+        PllInstance::Plli2s => {
+            assert!(pll.divp.is_none());
+            assert!(pll.divq.is_none());
+        }
+    }
+
     let p = pll.divp.map(|div| vco_freq / div);
     let q = pll.divq.map(|div| vco_freq / div);
     let r = pll.divr.map(|div| vco_freq / div);
@@ -293,6 +365,7 @@ fn init_pll(instance: PllInstance, config: Option<Pll>, input: &PllInput) -> Pll
             if let Some(divq) = pll.divq {
                 $w.set_pllq(divq);
             }
+            #[cfg(any(stm32f4, stm32f7))]
             if let Some(divr) = pll.divr {
                 $w.set_pllr(divr);
             }
@@ -309,6 +382,12 @@ fn init_pll(instance: PllInstance, config: Option<Pll>, input: &PllInput) -> Pll
         PllInstance::Plli2s => RCC.plli2scfgr().write(|w| {
             write_fields!(w);
         }),
+        #[cfg(stm32f2)]
+        PllInstance::Plli2s => RCC.plli2scfgr().write(|w| {
+            if let Some(divr) = pll.divr {
+                w.set_pllr(divr);
+            }
+        }),
         #[cfg(any(stm32f446, stm32f427, stm32f437, stm32f4x9, stm32f7))]
         PllInstance::Pllsai => RCC.pllsaicfgr().write(|w| {
             write_fields!(w);
@@ -321,22 +400,6 @@ fn init_pll(instance: PllInstance, config: Option<Pll>, input: &PllInput) -> Pll
     PllOutput { p, q, r }
 }
 
-fn flash_setup(clk: Hertz) {
-    use crate::pac::flash::vals::Latency;
-
-    // Be conservative with voltage ranges
-    const FLASH_LATENCY_STEP: u32 = 30_000_000;
-
-    let latency = (clk.0 - 1) / FLASH_LATENCY_STEP;
-    debug!("flash: latency={}", latency);
-
-    let latency = Latency::from_bits(latency as u8);
-    FLASH.acr().write(|w| {
-        w.set_latency(latency);
-    });
-    while FLASH.acr().read().latency() != latency {}
-}
-
 #[cfg(stm32f7)]
 mod max {
     use core::ops::RangeInclusive;
@@ -385,3 +448,22 @@ mod max {
     pub(crate) const PLL_IN: RangeInclusive<Hertz> = Hertz(1_000_000)..=Hertz(2_100_000);
     pub(crate) const PLL_VCO: RangeInclusive<Hertz> = Hertz(100_000_000)..=Hertz(432_000_000);
 }
+
+#[cfg(stm32f2)]
+mod max {
+    use core::ops::RangeInclusive;
+
+    use crate::time::Hertz;
+
+    pub(crate) const HSE_OSC: RangeInclusive<Hertz> = Hertz(4_000_000)..=Hertz(26_000_000);
+    pub(crate) const HSE_BYP: RangeInclusive<Hertz> = Hertz(1_000_000)..=Hertz(26_000_000);
+
+    pub(crate) const SYSCLK: RangeInclusive<Hertz> = Hertz(0)..=Hertz(120_000_000);
+
+    pub(crate) const HCLK: RangeInclusive<Hertz> = Hertz(0)..=Hertz(SYSCLK.end().0);
+    pub(crate) const PCLK1: RangeInclusive<Hertz> = Hertz(0)..=Hertz(SYSCLK.end().0 / 4);
+    pub(crate) const PCLK2: RangeInclusive<Hertz> = Hertz(0)..=Hertz(SYSCLK.end().0 / 2);
+
+    pub(crate) const PLL_IN: RangeInclusive<Hertz> = Hertz(0_950_000)..=Hertz(2_100_000);
+    pub(crate) const PLL_VCO: RangeInclusive<Hertz> = Hertz(192_000_000)..=Hertz(432_000_000);
+}

embassy-stm32/src/rcc/f2.rs

@@ -1,320 +0,0 @@
-use crate::pac::flash::vals::Latency;
-use crate::pac::rcc::vals::Sw;
-pub use crate::pac::rcc::vals::{
-    Hpre as AHBPrescaler, Pllm as PLLPreDiv, Plln as PLLMul, Pllp as PLLPDiv, Pllq as PLLQDiv, Pllsrc as PLLSrc,
-    Ppre as APBPrescaler,
-};
-use crate::pac::{FLASH, RCC};
-use crate::rcc::{set_freqs, Clocks};
-use crate::time::Hertz;
-
-/// HSI speed
-pub const HSI_FREQ: Hertz = Hertz(16_000_000);
-
-#[derive(Clone, Copy)]
-pub struct HSEConfig {
-    pub frequency: Hertz,
-    pub source: HSESrc,
-}
-
-/// System clock mux source
-#[derive(Clone, Copy)]
-pub enum ClockSrc {
-    HSE,
-    HSI,
-    PLL,
-}
-
-/// HSE clock source
-#[derive(Clone, Copy)]
-pub enum HSESrc {
-    /// Crystal/ceramic resonator
-    Crystal,
-    /// External clock source, HSE bypassed
-    Bypass,
-}
-
-#[derive(Clone, Copy)]
-pub struct PLLConfig {
-    pub pre_div: PLLPreDiv,
-    pub mul: PLLMul,
-    pub p_div: PLLPDiv,
-    pub q_div: PLLQDiv,
-}
-
-impl Default for PLLConfig {
-    fn default() -> Self {
-        PLLConfig {
-            pre_div: PLLPreDiv::DIV16,
-            mul: PLLMul::MUL192,
-            p_div: PLLPDiv::DIV2,
-            q_div: PLLQDiv::DIV4,
-        }
-    }
-}
-
-impl PLLConfig {
-    pub fn clocks(&self, src_freq: Hertz) -> PLLClocks {
-        let in_freq = src_freq / self.pre_div;
-        let vco_freq = src_freq / self.pre_div * self.mul;
-        let main_freq = vco_freq / self.p_div;
-        let pll48_freq = vco_freq / self.q_div;
-        PLLClocks {
-            in_freq,
-            vco_freq,
-            main_freq,
-            pll48_freq,
-        }
-    }
-}
-#[derive(Clone, Copy, PartialEq)]
-pub struct PLLClocks {
-    pub in_freq: Hertz,
-    pub vco_freq: Hertz,
-    pub main_freq: Hertz,
-    pub pll48_freq: Hertz,
-}
-
-/// Voltage range of the power supply used.
-///
-/// Used to calculate flash waitstates. See
-/// RM0033 - Table 3. Number of wait states according to Cortex®-M3 clock frequency
-pub enum VoltageScale {
-    /// 2.7 to 3.6 V
-    Range0,
-    /// 2.4 to 2.7 V
-    Range1,
-    /// 2.1 to 2.4 V
-    Range2,
-    /// 1.8 to 2.1 V
-    Range3,
-}
-
-impl VoltageScale {
-    const fn wait_states(&self, ahb_freq: Hertz) -> Option<Latency> {
-        let ahb_freq = ahb_freq.0;
-        // Reference: RM0033 - Table 3. Number of wait states according to Cortex®-M3 clock
-        // frequency
-        match self {
-            VoltageScale::Range3 => {
-                if ahb_freq <= 16_000_000 {
-                    Some(Latency::WS0)
-                } else if ahb_freq <= 32_000_000 {
-                    Some(Latency::WS1)
-                } else if ahb_freq <= 48_000_000 {
-                    Some(Latency::WS2)
-                } else if ahb_freq <= 64_000_000 {
-                    Some(Latency::WS3)
-                } else if ahb_freq <= 80_000_000 {
-                    Some(Latency::WS4)
-                } else if ahb_freq <= 96_000_000 {
-                    Some(Latency::WS5)
-                } else if ahb_freq <= 112_000_000 {
-                    Some(Latency::WS6)
-                } else if ahb_freq <= 120_000_000 {
-                    Some(Latency::WS7)
-                } else {
-                    None
-                }
-            }
-            VoltageScale::Range2 => {
-                if ahb_freq <= 18_000_000 {
-                    Some(Latency::WS0)
-                } else if ahb_freq <= 36_000_000 {
-                    Some(Latency::WS1)
-                } else if ahb_freq <= 54_000_000 {
-                    Some(Latency::WS2)
-                } else if ahb_freq <= 72_000_000 {
-                    Some(Latency::WS3)
-                } else if ahb_freq <= 90_000_000 {
-                    Some(Latency::WS4)
-                } else if ahb_freq <= 108_000_000 {
-                    Some(Latency::WS5)
-                } else if ahb_freq <= 120_000_000 {
-                    Some(Latency::WS6)
-                } else {
-                    None
-                }
-            }
-            VoltageScale::Range1 => {
-                if ahb_freq <= 24_000_000 {
-                    Some(Latency::WS0)
-                } else if ahb_freq <= 48_000_000 {
-                    Some(Latency::WS1)
-                } else if ahb_freq <= 72_000_000 {
-                    Some(Latency::WS2)
-                } else if ahb_freq <= 96_000_000 {
-                    Some(Latency::WS3)
-                } else if ahb_freq <= 120_000_000 {
-                    Some(Latency::WS4)
-                } else {
-                    None
-                }
-            }
-            VoltageScale::Range0 => {
-                if ahb_freq <= 30_000_000 {
-                    Some(Latency::WS0)
-                } else if ahb_freq <= 60_000_000 {
-                    Some(Latency::WS1)
-                } else if ahb_freq <= 90_000_000 {
-                    Some(Latency::WS2)
-                } else if ahb_freq <= 120_000_000 {
-                    Some(Latency::WS3)
-                } else {
-                    None
-                }
-            }
-        }
-    }
-}
-
-/// Clocks configuration
-pub struct Config {
-    pub hse: Option<HSEConfig>,
-    pub hsi: bool,
-    pub pll_mux: PLLSrc,
-    pub pll: PLLConfig,
-    pub mux: ClockSrc,
-    pub voltage: VoltageScale,
-    pub ahb_pre: AHBPrescaler,
-    pub apb1_pre: APBPrescaler,
-    pub apb2_pre: APBPrescaler,
-    pub ls: super::LsConfig,
-}
-
-impl Default for Config {
-    #[inline]
-    fn default() -> Config {
-        Config {
-            hse: None,
-            hsi: true,
-            pll_mux: PLLSrc::HSI,
-            pll: PLLConfig::default(),
-            voltage: VoltageScale::Range3,
-            mux: ClockSrc::HSI,
-            ahb_pre: AHBPrescaler::DIV1,
-            apb1_pre: APBPrescaler::DIV1,
-            apb2_pre: APBPrescaler::DIV1,
-            ls: Default::default(),
-        }
-    }
-}
-
-pub(crate) unsafe fn init(config: Config) {
-    // Make sure HSI is enabled
-    RCC.cr().write(|w| w.set_hsion(true));
-    while !RCC.cr().read().hsirdy() {}
-
-    if let Some(hse_config) = config.hse {
-        RCC.cr().modify(|w| {
-            w.set_hsebyp(match hse_config.source {
-                HSESrc::Bypass => true,
-                HSESrc::Crystal => false,
-            });
-            w.set_hseon(true)
-        });
-        while !RCC.cr().read().hserdy() {}
-    }
-
-    let pll_src_freq = match config.pll_mux {
-        PLLSrc::HSE => {
-            let hse_config = config
-                .hse
-                .unwrap_or_else(|| panic!("HSE must be configured to be used as PLL input"));
-            hse_config.frequency
-        }
-        PLLSrc::HSI => HSI_FREQ,
-    };
-
-    // Reference: STM32F215xx/217xx datasheet Table 33. Main PLL characteristics
-    let pll_clocks = config.pll.clocks(pll_src_freq);
-    assert!(Hertz(950_000) <= pll_clocks.in_freq && pll_clocks.in_freq <= Hertz(2_100_000));
-    assert!(Hertz(192_000_000) <= pll_clocks.vco_freq && pll_clocks.vco_freq <= Hertz(432_000_000));
-    assert!(Hertz(24_000_000) <= pll_clocks.main_freq && pll_clocks.main_freq <= Hertz(120_000_000));
-    // USB actually requires == 48 MHz, but other PLL48 peripherals are fine with <= 48MHz
-    assert!(pll_clocks.pll48_freq <= Hertz(48_000_000));
-
-    RCC.pllcfgr().write(|w| {
-        w.set_pllsrc(config.pll_mux);
-        w.set_pllm(config.pll.pre_div);
-        w.set_plln(config.pll.mul);
-        w.set_pllp(config.pll.p_div);
-        w.set_pllq(config.pll.q_div);
-    });
-
-    let (sys_clk, sw) = match config.mux {
-        ClockSrc::HSI => {
-            assert!(config.hsi, "HSI must be enabled to be used as system clock");
-            (HSI_FREQ, Sw::HSI)
-        }
-        ClockSrc::HSE => {
-            let hse_config = config
-                .hse
-                .unwrap_or_else(|| panic!("HSE must be configured to be used as PLL input"));
-            (hse_config.frequency, Sw::HSE)
-        }
-        ClockSrc::PLL => {
-            RCC.cr().modify(|w| w.set_pllon(true));
-            while !RCC.cr().read().pllrdy() {}
-            (pll_clocks.main_freq, Sw::PLL1_P)
-        }
-    };
-    // RM0033 Figure 9. Clock tree suggests max SYSCLK/HCLK is 168 MHz, but datasheet specifies PLL
-    // max output to be 120 MHz, so there's no way to get higher frequencies
-    assert!(sys_clk <= Hertz(120_000_000));
-
-    let ahb_freq = sys_clk / config.ahb_pre;
-    // Reference: STM32F215xx/217xx datasheet Table 13. General operating conditions
-    assert!(ahb_freq <= Hertz(120_000_000));
-
-    let (apb1_freq, apb1_tim_freq) = match config.apb1_pre {
-        APBPrescaler::DIV1 => (ahb_freq, ahb_freq),
-        pre => {
-            let freq = ahb_freq / pre;
-            (freq, Hertz(freq.0 * 2))
-        }
-    };
-    // Reference: STM32F215xx/217xx datasheet Table 13. General operating conditions
-    assert!(apb1_freq <= Hertz(30_000_000));
-
-    let (apb2_freq, apb2_tim_freq) = match config.apb2_pre {
-        APBPrescaler::DIV1 => (ahb_freq, ahb_freq),
-        pre => {
-            let freq = ahb_freq / pre;
-            (freq, Hertz(freq.0 * 2))
-        }
-    };
-    // Reference: STM32F215xx/217xx datasheet Table 13. General operating conditions
-    assert!(apb2_freq <= Hertz(60_000_000));
-
-    let flash_ws = unwrap!(config.voltage.wait_states(ahb_freq));
-    FLASH.acr().modify(|w| w.set_latency(flash_ws));
-
-    RCC.cfgr().modify(|w| {
-        w.set_sw(sw.into());
-        w.set_hpre(config.ahb_pre);
-        w.set_ppre1(config.apb1_pre);
-        w.set_ppre2(config.apb2_pre);
-    });
-    while RCC.cfgr().read().sws().to_bits() != sw.to_bits() {}
-
-    // Turn off HSI to save power if we don't need it
-    if !config.hsi {
-        RCC.cr().modify(|w| w.set_hsion(false));
-    }
-
-    let rtc = config.ls.init();
-
-    set_freqs(Clocks {
-        sys: sys_clk,
-        hclk1: ahb_freq,
-        hclk2: ahb_freq,
-        hclk3: ahb_freq,
-        pclk1: apb1_freq,
-        pclk1_tim: apb1_tim_freq,
-        pclk2: apb2_freq,
-        pclk2_tim: apb2_tim_freq,
-        pll1_q: Some(pll_clocks.pll48_freq),
-        rtc,
-    });
-}

embassy-stm32/src/rcc/g0.rs

@@ -28,7 +28,7 @@ pub enum ClockSrc {
 #[derive(Clone, Copy)]
 pub struct PllConfig {
     /// The source from which the PLL receives a clock signal
-    pub source: PllSrc,
+    pub source: PllSource,
     /// The initial divisor of that clock signal
     pub m: Pllm,
     /// The PLL VCO multiplier, which must be in the range `8..=86`.
@@ -48,7 +48,7 @@ impl Default for PllConfig {
     fn default() -> PllConfig {
         // HSI / 1 * 8 / 2 = 64 MHz
         PllConfig {
-            source: PllSrc::HSI,
+            source: PllSource::HSI,
             m: Pllm::DIV1,
             n: Plln::MUL8,
             r: Pllr::DIV2,
@@ -59,7 +59,7 @@ impl Default for PllConfig {
 }
 
 #[derive(Clone, Copy, Eq, PartialEq)]
-pub enum PllSrc {
+pub enum PllSource {
     HSI,
     HSE(Hertz),
 }
@@ -89,8 +89,8 @@ impl Default for Config {
 impl PllConfig {
     pub(crate) fn init(self) -> Hertz {
         let (src, input_freq) = match self.source {
-            PllSrc::HSI => (vals::Pllsrc::HSI, HSI_FREQ),
-            PllSrc::HSE(freq) => (vals::Pllsrc::HSE, freq),
+            PllSource::HSI => (vals::Pllsrc::HSI, HSI_FREQ),
+            PllSource::HSE(freq) => (vals::Pllsrc::HSE, freq),
         };
 
         let m_freq = input_freq / self.m;
@@ -121,11 +121,11 @@ impl PllConfig {
         // > 3. Change the desired parameter.
         // Enable whichever clock source we're using, and wait for it to become ready
         match self.source {
-            PllSrc::HSI => {
+            PllSource::HSI => {
                 RCC.cr().write(|w| w.set_hsion(true));
                 while !RCC.cr().read().hsirdy() {}
             }
-            PllSrc::HSE(_) => {
+            PllSource::HSE(_) => {
                 RCC.cr().write(|w| w.set_hseon(true));
                 while !RCC.cr().read().hserdy() {}
             }

embassy-stm32/src/rcc/g4.rs

@@ -7,7 +7,6 @@ pub use crate::pac::rcc::vals::{
     Pllr as PllR, Ppre as APBPrescaler,
 };
 use crate::pac::{PWR, RCC};
-use crate::rcc::sealed::RccPeripheral;
 use crate::rcc::{set_freqs, Clocks};
 use crate::time::Hertz;
 
@@ -24,16 +23,16 @@ pub enum ClockSrc {
 
 /// PLL clock input source
 #[derive(Clone, Copy, Debug)]
-pub enum PllSrc {
+pub enum PllSource {
     HSI,
     HSE(Hertz),
 }
 
-impl Into<Pllsrc> for PllSrc {
+impl Into<Pllsrc> for PllSource {
     fn into(self) -> Pllsrc {
         match self {
-            PllSrc::HSE(..) => Pllsrc::HSE,
-            PllSrc::HSI => Pllsrc::HSI,
+            PllSource::HSE(..) => Pllsrc::HSE,
+            PllSource::HSI => Pllsrc::HSI,
         }
     }
 }
@@ -45,7 +44,7 @@ impl Into<Pllsrc> for PllSrc {
 /// frequency ranges for each of these settings.
 pub struct Pll {
     /// PLL Source clock selection.
-    pub source: PllSrc,
+    pub source: PllSource,
 
     /// PLL pre-divider
     pub prediv_m: PllM,
@@ -67,23 +66,13 @@ pub struct Pll {
 pub enum Clock48MhzSrc {
     /// Use the High Speed Internal Oscillator. For USB usage, the CRS must be used to calibrate the
     /// oscillator to comply with the USB specification for oscillator tolerance.
-    Hsi48(Option<CrsConfig>),
+    Hsi48(super::Hsi48Config),
     /// Use the PLLQ output. The PLL must be configured to output a 48MHz clock. For USB usage the
     /// PLL needs to be using the HSE source to comply with the USB specification for oscillator
     /// tolerance.
     PllQ,
 }
 
-/// Sets the sync source for the Clock Recovery System (CRS).
-pub enum CrsSyncSource {
-    /// Use an external GPIO to sync the CRS.
-    Gpio,
-    /// Use the Low Speed External oscillator to sync the CRS.
-    Lse,
-    /// Use the USB SOF to sync the CRS.
-    Usb,
-}
-
 /// Clocks configutation
 pub struct Config {
     pub mux: ClockSrc,
@@ -102,12 +91,6 @@ pub struct Config {
     pub ls: super::LsConfig,
 }
 
-/// Configuration for the Clock Recovery System (CRS) used to trim the HSI48 oscillator.
-pub struct CrsConfig {
-    /// Sync source for the CRS.
-    pub sync_src: CrsSyncSource,
-}
-
 impl Default for Config {
     #[inline]
     fn default() -> Config {
@@ -118,7 +101,7 @@ impl Default for Config {
             apb2_pre: APBPrescaler::DIV1,
             low_power_run: false,
             pll: None,
-            clock_48mhz_src: Some(Clock48MhzSrc::Hsi48(None)),
+            clock_48mhz_src: Some(Clock48MhzSrc::Hsi48(Default::default())),
             adc12_clock_source: Adcsel::DISABLE,
             adc345_clock_source: Adcsel::DISABLE,
             ls: Default::default(),
@@ -135,13 +118,13 @@ pub struct PllFreq {
 pub(crate) unsafe fn init(config: Config) {
     let pll_freq = config.pll.map(|pll_config| {
         let src_freq = match pll_config.source {
-            PllSrc::HSI => {
+            PllSource::HSI => {
                 RCC.cr().write(|w| w.set_hsion(true));
                 while !RCC.cr().read().hsirdy() {}
 
                 HSI_FREQ
             }
-            PllSrc::HSE(freq) => {
+            PllSource::HSE(freq) => {
                 RCC.cr().write(|w| w.set_hseon(true));
                 while !RCC.cr().read().hserdy() {}
                 freq
@@ -288,33 +271,8 @@ pub(crate) unsafe fn init(config: Config) {
 
                 crate::pac::rcc::vals::Clk48sel::PLL1_Q
             }
-            Clock48MhzSrc::Hsi48(crs_config) => {
-                // Enable HSI48
-                RCC.crrcr().modify(|w| w.set_hsi48on(true));
-                // Wait for HSI48 to turn on
-                while RCC.crrcr().read().hsi48rdy() == false {}
-
-                // Enable and setup CRS if needed
-                if let Some(crs_config) = crs_config {
-                    crate::peripherals::CRS::enable_and_reset();
-
-                    let sync_src = match crs_config.sync_src {
-                        CrsSyncSource::Gpio => crate::pac::crs::vals::Syncsrc::GPIO,
-                        CrsSyncSource::Lse => crate::pac::crs::vals::Syncsrc::LSE,
-                        CrsSyncSource::Usb => crate::pac::crs::vals::Syncsrc::USB,
-                    };
-
-                    crate::pac::CRS.cfgr().modify(|w| {
-                        w.set_syncsrc(sync_src);
-                    });
-
-                    // These are the correct settings for standard USB operation. If other settings
-                    // are needed there will need to be additional config options for the CRS.
-                    crate::pac::CRS.cr().modify(|w| {
-                        w.set_autotrimen(true);
-                        w.set_cen(true);
-                    });
-                }
+            Clock48MhzSrc::Hsi48(config) => {
+                super::init_hsi48(config);
                 crate::pac::rcc::vals::Clk48sel::HSI48
             }
         };

embassy-stm32/src/rcc/h.rs

@@ -21,9 +21,6 @@ pub const HSI_FREQ: Hertz = Hertz(64_000_000);
 /// CSI speed
 pub const CSI_FREQ: Hertz = Hertz(4_000_000);
 
-/// HSI48 speed
-pub const HSI48_FREQ: Hertz = Hertz(48_000_000);
-
 const VCO_RANGE: RangeInclusive<Hertz> = Hertz(150_000_000)..=Hertz(420_000_000);
 #[cfg(any(stm32h5, pwr_h7rm0455))]
 const VCO_WIDE_RANGE: RangeInclusive<Hertz> = Hertz(128_000_000)..=Hertz(560_000_000);
@@ -126,7 +123,7 @@ pub struct Config {
     pub hsi: Option<HSIPrescaler>,
     pub hse: Option<Hse>,
     pub csi: bool,
-    pub hsi48: bool,
+    pub hsi48: Option<super::Hsi48Config>,
     pub sys: Sysclk,
 
     pub pll1: Option<Pll>,
@@ -155,7 +152,7 @@ impl Default for Config {
             hsi: Some(HSIPrescaler::DIV1),
             hse: None,
             csi: false,
-            hsi48: false,
+            hsi48: Some(Default::default()),
             sys: Sysclk::HSI,
             pll1: None,
             pll2: None,
@@ -301,14 +298,7 @@ pub(crate) unsafe fn init(config: Config) {
     };
 
     // Configure HSI48.
-    RCC.cr().modify(|w| w.set_hsi48on(config.hsi48));
-    let _hsi48 = match config.hsi48 {
-        false => None,
-        true => {
-            while !RCC.cr().read().hsi48rdy() {}
-            Some(CSI_FREQ)
-        }
-    };
+    let _hsi48 = config.hsi48.map(super::init_hsi48);
 
     // Configure CSI.
     RCC.cr().modify(|w| w.set_csion(config.csi));

embassy-stm32/src/rcc/hsi48.rs

@@ -0,0 +1,62 @@
+#![allow(unused)]
+
+use crate::pac::crs::vals::Syncsrc;
+use crate::pac::{CRS, RCC};
+use crate::rcc::sealed::RccPeripheral;
+use crate::time::Hertz;
+
+/// HSI48 speed
+pub const HSI48_FREQ: Hertz = Hertz(48_000_000);
+
+/// Configuration for the HSI48 clock
+#[derive(Clone, Copy, Debug)]
+pub struct Hsi48Config {
+    /// Enable CRS Sync from USB Start Of Frame (SOF) events.
+    /// Required if HSI48 is going to be used as USB clock.
+    ///
+    /// Other use cases of CRS are not supported yet.
+    pub sync_from_usb: bool,
+}
+
+impl Default for Hsi48Config {
+    fn default() -> Self {
+        Self { sync_from_usb: false }
+    }
+}
+
+pub(crate) fn init_hsi48(config: Hsi48Config) -> Hertz {
+    // Enable VREFINT reference for HSI48 oscillator
+    #[cfg(stm32l0)]
+    crate::pac::SYSCFG.cfgr3().modify(|w| {
+        w.set_enref_hsi48(true);
+        w.set_en_vrefint(true);
+    });
+
+    // Enable HSI48
+    #[cfg(not(any(stm32u5, stm32g0, stm32h5, stm32h7, stm32u5, stm32wba, stm32f0)))]
+    let r = RCC.crrcr();
+    #[cfg(any(stm32u5, stm32g0, stm32h5, stm32h7, stm32u5, stm32wba))]
+    let r = RCC.cr();
+    #[cfg(any(stm32f0))]
+    let r = RCC.cr2();
+
+    r.modify(|w| w.set_hsi48on(true));
+    while r.read().hsi48rdy() == false {}
+
+    if config.sync_from_usb {
+        crate::peripherals::CRS::enable_and_reset();
+
+        CRS.cfgr().modify(|w| {
+            w.set_syncsrc(Syncsrc::USB);
+        });
+
+        // These are the correct settings for standard USB operation. If other settings
+        // are needed there will need to be additional config options for the CRS.
+        crate::pac::CRS.cr().modify(|w| {
+            w.set_autotrimen(true);
+            w.set_cen(true);
+        });
+    }
+
+    HSI48_FREQ
+}

embassy-stm32/src/rcc/l.rs

@@ -1,12 +1,13 @@
+#[cfg(any(stm32l0, stm32l1))]
+pub use crate::pac::pwr::vals::Vos as VoltageScale;
 use crate::pac::rcc::regs::Cfgr;
-#[cfg(any(stm32l4, stm32l5, stm32wb))]
+#[cfg(any(stm32l4, stm32l5, stm32wb, stm32wl))]
+pub use crate::pac::rcc::vals::Adcsel as AdcClockSource;
+#[cfg(any(rcc_l0_v2, stm32l4, stm32l5, stm32wb))]
 pub use crate::pac::rcc::vals::Clk48sel as Clk48Src;
 #[cfg(any(stm32wb, stm32wl))]
 pub use crate::pac::rcc::vals::Hsepre as HsePrescaler;
-pub use crate::pac::rcc::vals::{
-    Hpre as AHBPrescaler, Msirange as MSIRange, Pllm as PllPreDiv, Plln as PllMul, Pllp as PllPDiv, Pllq as PllQDiv,
-    Pllr as PllRDiv, Pllsrc as PLLSource, Ppre as APBPrescaler, Sw as ClockSrc,
-};
+pub use crate::pac::rcc::vals::{Hpre as AHBPrescaler, Msirange as MSIRange, Ppre as APBPrescaler, Sw as ClockSrc};
 use crate::pac::{FLASH, RCC};
 use crate::rcc::{set_freqs, Clocks};
 use crate::time::Hertz;
@@ -33,33 +34,14 @@ pub struct Hse {
     pub prescaler: HsePrescaler,
 }
 
-#[derive(Clone, Copy)]
-pub struct Pll {
-    /// PLL source
-    pub source: PLLSource,
-
-    /// PLL pre-divider (DIVM).
-    pub prediv: PllPreDiv,
-
-    /// PLL multiplication factor.
-    pub mul: PllMul,
-
-    /// PLL P division factor. If None, PLL P output is disabled.
-    pub divp: Option<PllPDiv>,
-    /// PLL Q division factor. If None, PLL Q output is disabled.
-    pub divq: Option<PllQDiv>,
-    /// PLL R division factor. If None, PLL R output is disabled.
-    pub divr: Option<PllRDiv>,
-}
-
-/// Clocks configutation
+/// Clocks configuration
 pub struct Config {
     // base clock sources
     pub msi: Option<MSIRange>,
     pub hsi: bool,
     pub hse: Option<Hse>,
-    #[cfg(any(all(stm32l4, not(any(stm32l47x, stm32l48x))), stm32l5, stm32wb))]
-    pub hsi48: bool,
+    #[cfg(crs)]
+    pub hsi48: Option<super::Hsi48Config>,
 
     // pll
     pub pll: Option<Pll>,
@@ -79,11 +61,17 @@ pub struct Config {
     pub shared_ahb_pre: AHBPrescaler,
 
     // muxes
-    #[cfg(any(stm32l4, stm32l5, stm32wb))]
+    #[cfg(any(rcc_l0_v2, stm32l4, stm32l5, stm32wb))]
     pub clk48_src: Clk48Src,
 
     // low speed LSI/LSE/RTC
     pub ls: super::LsConfig,
+
+    #[cfg(any(stm32l4, stm32l5, stm32wb, stm32wl))]
+    pub adc_clock_source: AdcClockSource,
+
+    #[cfg(any(stm32l0, stm32l1))]
+    pub voltage_scale: VoltageScale,
 }
 
 impl Default for Config {
@@ -106,11 +94,15 @@ impl Default for Config {
             pllsai1: None,
             #[cfg(any(stm32l47x, stm32l48x, stm32l49x, stm32l4ax, rcc_l4plus, stm32l5))]
             pllsai2: None,
-            #[cfg(any(all(stm32l4, not(any(stm32l47x, stm32l48x))), stm32l5, stm32wb))]
-            hsi48: true,
-            #[cfg(any(stm32l4, stm32l5, stm32wb))]
+            #[cfg(crs)]
+            hsi48: Some(Default::default()),
+            #[cfg(any(rcc_l0_v2, stm32l4, stm32l5, stm32wb))]
             clk48_src: Clk48Src::HSI48,
             ls: Default::default(),
+            #[cfg(any(stm32l4, stm32l5, stm32wb, stm32wl))]
+            adc_clock_source: AdcClockSource::SYS,
+            #[cfg(any(stm32l0, stm32l1))]
+            voltage_scale: VoltageScale::RANGE1,
         }
     }
 }
@@ -123,7 +115,8 @@ pub const WPAN_DEFAULT: Config = Config {
         prescaler: HsePrescaler::DIV1,
     }),
     mux: ClockSrc::PLL1_R,
-    hsi48: true,
+    #[cfg(crs)]
+    hsi48: Some(super::Hsi48Config { sync_from_usb: false }),
     msi: None,
     hsi: false,
     clk48_src: Clk48Src::PLL1_Q,
@@ -131,7 +124,7 @@ pub const WPAN_DEFAULT: Config = Config {
     ls: super::LsConfig::default_lse(),
 
     pll: Some(Pll {
-        source: PLLSource::HSE,
+        source: PllSource::HSE,
         prediv: PllPreDiv::DIV2,
         mul: PllMul::MUL12,
         divp: Some(PllPDiv::DIV3), // 32 / 2 * 12 / 3 = 64Mhz
@@ -145,22 +138,29 @@ pub const WPAN_DEFAULT: Config = Config {
     shared_ahb_pre: AHBPrescaler::DIV1,
     apb1_pre: APBPrescaler::DIV1,
     apb2_pre: APBPrescaler::DIV1,
+    adc_clock_source: AdcClockSource::SYS,
 };
 
+fn msi_enable(range: MSIRange) {
+    #[cfg(any(stm32l4, stm32l5, stm32wb, stm32wl))]
+    RCC.cr().modify(|w| {
+        #[cfg(not(stm32wb))]
+        w.set_msirgsel(crate::pac::rcc::vals::Msirgsel::CR);
+        w.set_msirange(range);
+        w.set_msipllen(false);
+    });
+    #[cfg(any(stm32l0, stm32l1))]
+    RCC.icscr().modify(|w| w.set_msirange(range));
+
+    RCC.cr().modify(|w| w.set_msion(true));
+    while !RCC.cr().read().msirdy() {}
+}
+
 pub(crate) unsafe fn init(config: Config) {
     // Switch to MSI to prevent problems with PLL configuration.
     if !RCC.cr().read().msion() {
         // Turn on MSI and configure it to 4MHz.
-        RCC.cr().modify(|w| {
-            #[cfg(not(stm32wb))]
-            w.set_msirgsel(crate::pac::rcc::vals::Msirgsel::CR);
-            w.set_msirange(MSIRange::RANGE4M);
-            w.set_msipllen(false);
-            w.set_msion(true)
-        });
-
-        // Wait until MSI is running
-        while !RCC.cr().read().msirdy() {}
+        msi_enable(MSIRange::RANGE4M)
     }
     if RCC.cfgr().read().sws() != ClockSrc::MSI {
         // Set MSI as a clock source, reset prescalers.
@@ -169,6 +169,14 @@ pub(crate) unsafe fn init(config: Config) {
         while RCC.cfgr().read().sws() != ClockSrc::MSI {}
     }
 
+    // Set voltage scale
+    #[cfg(any(stm32l0, stm32l1))]
+    {
+        while crate::pac::PWR.csr().read().vosf() {}
+        crate::pac::PWR.cr().write(|w| w.set_vos(config.voltage_scale));
+        while crate::pac::PWR.csr().read().vosf() {}
+    }
+
     #[cfg(stm32l5)]
     crate::pac::PWR.cr1().modify(|w| {
         w.set_vos(crate::pac::pwr::vals::Vos::RANGE0);
@@ -177,24 +185,16 @@ pub(crate) unsafe fn init(config: Config) {
     let rtc = config.ls.init();
 
     let msi = config.msi.map(|range| {
-        // Enable MSI
-        RCC.cr().modify(|w| {
-            #[cfg(not(stm32wb))]
-            w.set_msirgsel(crate::pac::rcc::vals::Msirgsel::CR);
-            w.set_msirange(range);
-            w.set_msion(true);
-
-            // If LSE is enabled, enable calibration of MSI
-            w.set_msipllen(config.ls.lse.is_some());
-        });
-        while !RCC.cr().read().msirdy() {}
-
-        // Enable as clock source for USB, RNG if running at 48 MHz
-        if range == MSIRange::RANGE48M {}
-
+        msi_enable(range);
         msirange_to_hertz(range)
     });
 
+    // If LSE is enabled and the right freq, enable calibration of MSI
+    #[cfg(any(stm32l4, stm32l5, stm32wb, stm32wl))]
+    if config.ls.lse.map(|x| x.frequency) == Some(Hertz(32_768)) {
+        RCC.cr().modify(|w| w.set_msipllen(true));
+    }
+
     let hsi = config.hsi.then(|| {
         RCC.cr().modify(|w| w.set_hsion(true));
         while !RCC.cr().read().hsirdy() {}
@@ -215,15 +215,13 @@ pub(crate) unsafe fn init(config: Config) {
         hse.freq
     });
 
-    #[cfg(any(all(stm32l4, not(any(stm32l47x, stm32l48x))), stm32l5, stm32wb))]
-    let hsi48 = config.hsi48.then(|| {
-        RCC.crrcr().modify(|w| w.set_hsi48on(true));
-        while !RCC.crrcr().read().hsi48rdy() {}
-
-        Hertz(48_000_000)
+    #[cfg(crs)]
+    let _hsi48 = config.hsi48.map(|config| {
+        //
+        super::init_hsi48(config)
     });
-    #[cfg(any(stm32l47x, stm32l48x))]
-    let hsi48 = None;
+    #[cfg(not(crs))]
+    let _hsi48: Option<Hertz> = None;
 
     let _plls = [
         &config.pll,
@@ -254,7 +252,12 @@ pub(crate) unsafe fn init(config: Config) {
         }),
     };
 
-    let pll_input = PllInput { hse, hsi, msi };
+    let pll_input = PllInput {
+        hse,
+        hsi,
+        #[cfg(any(stm32l4, stm32l5, stm32wb, stm32wl))]
+        msi,
+    };
     let pll = init_pll(PllInstance::Pll, config.pll, &pll_input);
     #[cfg(any(stm32l4, stm32l5, stm32wb))]
     let pllsai1 = init_pll(PllInstance::Pllsai1, config.pllsai1, &pll_input);
@@ -268,13 +271,16 @@ pub(crate) unsafe fn init(config: Config) {
         ClockSrc::PLL1_R => pll.r.unwrap(),
     };
 
-    #[cfg(stm32l4)]
+    #[cfg(any(rcc_l0_v2, stm32l4, stm32l5, stm32wb))]
     RCC.ccipr().modify(|w| w.set_clk48sel(config.clk48_src));
-    #[cfg(stm32l5)]
-    RCC.ccipr1().modify(|w| w.set_clk48sel(config.clk48_src));
+    #[cfg(any(rcc_l0_v2))]
+    let _clk48 = match config.clk48_src {
+        Clk48Src::HSI48 => _hsi48,
+        Clk48Src::PLL1_VCO_DIV_2 => pll.clk48,
+    };
     #[cfg(any(stm32l4, stm32l5, stm32wb))]
     let _clk48 = match config.clk48_src {
-        Clk48Src::HSI48 => hsi48,
+        Clk48Src::HSI48 => _hsi48,
         Clk48Src::MSI => msi,
         Clk48Src::PLLSAI1_Q => pllsai1.q,
         Clk48Src::PLL1_Q => pll.q,
@@ -288,16 +294,23 @@ pub(crate) unsafe fn init(config: Config) {
     let hclk1 = sys_clk / config.ahb_pre;
     let (pclk1, pclk1_tim) = super::util::calc_pclk(hclk1, config.apb1_pre);
     let (pclk2, pclk2_tim) = super::util::calc_pclk(hclk1, config.apb2_pre);
-    #[cfg(not(any(stm32wl5x, stm32wb)))]
+    #[cfg(any(stm32l4, stm32l5, stm32wlex))]
     let hclk2 = hclk1;
     #[cfg(any(stm32wl5x, stm32wb))]
     let hclk2 = sys_clk / config.core2_ahb_pre;
-    #[cfg(not(any(stm32wl, stm32wb)))]
+    #[cfg(any(stm32l4, stm32l5, stm32wlex))]
     let hclk3 = hclk1;
-    #[cfg(any(stm32wl, stm32wb))]
+    #[cfg(any(stm32wl5x, stm32wb))]
     let hclk3 = sys_clk / config.shared_ahb_pre;
 
     // Set flash wait states
+    #[cfg(any(stm32l0, stm32l1))]
+    let latency = match (config.voltage_scale, sys_clk.0) {
+        (VoltageScale::RANGE1, ..=16_000_000) => false,
+        (VoltageScale::RANGE2, ..=8_000_000) => false,
+        (VoltageScale::RANGE3, ..=4_200_000) => false,
+        _ => true,
+    };
     #[cfg(stm32l4)]
     let latency = match hclk1.0 {
         0..=16_000_000 => 0,
@@ -333,6 +346,10 @@ pub(crate) unsafe fn init(config: Config) {
         _ => 4,
     };
 
+    #[cfg(stm32l1)]
+    FLASH.acr().write(|w| w.set_acc64(true));
+    #[cfg(not(stm32l5))]
+    FLASH.acr().modify(|w| w.set_prften(true));
     FLASH.acr().modify(|w| w.set_latency(latency));
     while FLASH.acr().read().latency() != latency {}
 
@@ -344,6 +361,9 @@ pub(crate) unsafe fn init(config: Config) {
     });
     while RCC.cfgr().read().sws() != config.mux {}
 
+    #[cfg(any(stm32l4, stm32l5, stm32wb, stm32wl))]
+    RCC.ccipr().modify(|w| w.set_adcsel(config.adc_clock_source));
+
     #[cfg(any(stm32wl, stm32wb))]
     {
         RCC.extcfgr().modify(|w| {
@@ -359,7 +379,9 @@ pub(crate) unsafe fn init(config: Config) {
     set_freqs(Clocks {
         sys: sys_clk,
         hclk1,
+        #[cfg(any(stm32l4, stm32l5, stm32wb, stm32wl))]
         hclk2,
+        #[cfg(any(stm32l4, stm32l5, stm32wb, stm32wl))]
         hclk3,
         pclk1,
         pclk2,
@@ -387,6 +409,12 @@ pub(crate) unsafe fn init(config: Config) {
     });
 }
 
+#[cfg(any(stm32l0, stm32l1))]
+fn msirange_to_hertz(range: MSIRange) -> Hertz {
+    Hertz(32_768 * (1 << (range as u8 + 1)))
+}
+
+#[cfg(any(stm32l4, stm32l5, stm32wb, stm32wl))]
 fn msirange_to_hertz(range: MSIRange) -> Hertz {
     match range {
         MSIRange::RANGE100K => Hertz(100_000),
@@ -405,20 +433,6 @@ fn msirange_to_hertz(range: MSIRange) -> Hertz {
     }
 }
 
-struct PllInput {
-    hsi: Option<Hertz>,
-    hse: Option<Hertz>,
-    msi: Option<Hertz>,
-}
-
-#[allow(unused)]
-#[derive(Default)]
-struct PllOutput {
-    p: Option<Hertz>,
-    q: Option<Hertz>,
-    r: Option<Hertz>,
-}
-
 #[derive(PartialEq, Eq, Clone, Copy)]
 enum PllInstance {
     Pll,
@@ -447,77 +461,182 @@ fn pll_enable(instance: PllInstance, enabled: bool) {
     }
 }
 
-fn init_pll(instance: PllInstance, config: Option<Pll>, input: &PllInput) -> PllOutput {
-    // Disable PLL
-    pll_enable(instance, false);
+pub use pll::*;
 
-    let Some(pll) = config else { return PllOutput::default() };
+#[cfg(any(stm32l0, stm32l1))]
+mod pll {
+    use super::{pll_enable, PllInstance};
+    pub use crate::pac::rcc::vals::{Plldiv as PllDiv, Pllmul as PllMul, Pllsrc as PllSource};
+    use crate::pac::RCC;
+    use crate::time::Hertz;
 
-    let pll_src = match pll.source {
-        PLLSource::DISABLE => panic!("must not select PLL source as DISABLE"),
-        PLLSource::HSE => input.hse,
-        PLLSource::HSI => input.hsi,
-        PLLSource::MSI => input.msi,
-    };
+    #[derive(Clone, Copy)]
+    pub struct Pll {
+        /// PLL source
+        pub source: PllSource,
 
-    let pll_src = pll_src.unwrap();
+        /// PLL multiplication factor.
+        pub mul: PllMul,
 
-    let vco_freq = pll_src / pll.prediv * pll.mul;
-
-    let p = pll.divp.map(|div| vco_freq / div);
-    let q = pll.divq.map(|div| vco_freq / div);
-    let r = pll.divr.map(|div| vco_freq / div);
-
-    #[cfg(stm32l5)]
-    if instance == PllInstance::Pllsai2 {
-        assert!(q.is_none(), "PLLSAI2_Q is not available on L5");
-        assert!(r.is_none(), "PLLSAI2_R is not available on L5");
+        /// PLL main output division factor.
+        pub div: PllDiv,
     }
 
-    macro_rules! write_fields {
-        ($w:ident) => {
-            $w.set_plln(pll.mul);
-            if let Some(divp) = pll.divp {
-                $w.set_pllp(divp);
-                $w.set_pllpen(true);
-            }
-            if let Some(divq) = pll.divq {
-                $w.set_pllq(divq);
-                $w.set_pllqen(true);
-            }
-            if let Some(divr) = pll.divr {
-                $w.set_pllr(divr);
-                $w.set_pllren(true);
-            }
+    pub(super) struct PllInput {
+        pub hsi: Option<Hertz>,
+        pub hse: Option<Hertz>,
+    }
+
+    #[allow(unused)]
+    #[derive(Default)]
+    pub(super) struct PllOutput {
+        pub r: Option<Hertz>,
+        pub clk48: Option<Hertz>,
+    }
+
+    pub(super) fn init_pll(instance: PllInstance, config: Option<Pll>, input: &PllInput) -> PllOutput {
+        // Disable PLL
+        pll_enable(instance, false);
+
+        let Some(pll) = config else { return PllOutput::default() };
+
+        let pll_src = match pll.source {
+            PllSource::HSE => unwrap!(input.hse),
+            PllSource::HSI => unwrap!(input.hsi),
         };
+
+        let vco_freq = pll_src * pll.mul;
+
+        let r = vco_freq / pll.div;
+        let clk48 = (vco_freq == Hertz(96_000_000)).then_some(Hertz(48_000_000));
+
+        assert!(r <= Hertz(32_000_000));
+
+        RCC.cfgr().write(move |w| {
+            w.set_pllmul(pll.mul);
+            w.set_plldiv(pll.div);
+            w.set_pllsrc(pll.source);
+        });
+
+        // Enable PLL
+        pll_enable(instance, true);
+
+        PllOutput { r: Some(r), clk48 }
+    }
+}
+
+#[cfg(any(stm32l4, stm32l5, stm32wb, stm32wl))]
+mod pll {
+    use super::{pll_enable, PllInstance};
+    pub use crate::pac::rcc::vals::{
+        Pllm as PllPreDiv, Plln as PllMul, Pllp as PllPDiv, Pllq as PllQDiv, Pllr as PllRDiv, Pllsrc as PllSource,
+    };
+    use crate::pac::RCC;
+    use crate::time::Hertz;
+
+    #[derive(Clone, Copy)]
+    pub struct Pll {
+        /// PLL source
+        pub source: PllSource,
+
+        /// PLL pre-divider (DIVM).
+        pub prediv: PllPreDiv,
+
+        /// PLL multiplication factor.
+        pub mul: PllMul,
+
+        /// PLL P division factor. If None, PLL P output is disabled.
+        pub divp: Option<PllPDiv>,
+        /// PLL Q division factor. If None, PLL Q output is disabled.
+        pub divq: Option<PllQDiv>,
+        /// PLL R division factor. If None, PLL R output is disabled.
+        pub divr: Option<PllRDiv>,
+    }
+
+    pub(super) struct PllInput {
+        pub hsi: Option<Hertz>,
+        pub hse: Option<Hertz>,
+        pub msi: Option<Hertz>,
+    }
+
+    #[allow(unused)]
+    #[derive(Default)]
+    pub(super) struct PllOutput {
+        pub p: Option<Hertz>,
+        pub q: Option<Hertz>,
+        pub r: Option<Hertz>,
+    }
+
+    pub(super) fn init_pll(instance: PllInstance, config: Option<Pll>, input: &PllInput) -> PllOutput {
+        // Disable PLL
+        pll_enable(instance, false);
+
+        let Some(pll) = config else { return PllOutput::default() };
+
+        let pll_src = match pll.source {
+            PllSource::DISABLE => panic!("must not select PLL source as DISABLE"),
+            PllSource::HSE => unwrap!(input.hse),
+            PllSource::HSI => unwrap!(input.hsi),
+            PllSource::MSI => unwrap!(input.msi),
+        };
+
+        let vco_freq = pll_src / pll.prediv * pll.mul;
+
+        let p = pll.divp.map(|div| vco_freq / div);
+        let q = pll.divq.map(|div| vco_freq / div);
+        let r = pll.divr.map(|div| vco_freq / div);
+
+        #[cfg(stm32l5)]
+        if instance == PllInstance::Pllsai2 {
+            assert!(q.is_none(), "PLLSAI2_Q is not available on L5");
+            assert!(r.is_none(), "PLLSAI2_R is not available on L5");
+        }
+
+        macro_rules! write_fields {
+            ($w:ident) => {
+                $w.set_plln(pll.mul);
+                if let Some(divp) = pll.divp {
+                    $w.set_pllp(divp);
+                    $w.set_pllpen(true);
+                }
+                if let Some(divq) = pll.divq {
+                    $w.set_pllq(divq);
+                    $w.set_pllqen(true);
+                }
+                if let Some(divr) = pll.divr {
+                    $w.set_pllr(divr);
+                    $w.set_pllren(true);
+                }
+            };
+        }
+
+        match instance {
+            PllInstance::Pll => RCC.pllcfgr().write(|w| {
+                w.set_pllm(pll.prediv);
+                w.set_pllsrc(pll.source);
+                write_fields!(w);
+            }),
+            #[cfg(any(stm32l4, stm32l5, stm32wb))]
+            PllInstance::Pllsai1 => RCC.pllsai1cfgr().write(|w| {
+                #[cfg(any(rcc_l4plus, stm32l5))]
+                w.set_pllm(pll.prediv);
+                #[cfg(stm32l5)]
+                w.set_pllsrc(pll.source);
+                write_fields!(w);
+            }),
+            #[cfg(any(stm32l47x, stm32l48x, stm32l49x, stm32l4ax, rcc_l4plus, stm32l5))]
+            PllInstance::Pllsai2 => RCC.pllsai2cfgr().write(|w| {
+                #[cfg(any(rcc_l4plus, stm32l5))]
+                w.set_pllm(pll.prediv);
+                #[cfg(stm32l5)]
+                w.set_pllsrc(pll.source);
+                write_fields!(w);
+            }),
+        }
+
+        // Enable PLL
+        pll_enable(instance, true);
+
+        PllOutput { p, q, r }
     }
-
-    match instance {
-        PllInstance::Pll => RCC.pllcfgr().write(|w| {
-            w.set_pllm(pll.prediv);
-            w.set_pllsrc(pll.source);
-            write_fields!(w);
-        }),
-        #[cfg(any(stm32l4, stm32l5, stm32wb))]
-        PllInstance::Pllsai1 => RCC.pllsai1cfgr().write(|w| {
-            #[cfg(any(rcc_l4plus, stm32l5))]
-            w.set_pllm(pll.prediv);
-            #[cfg(stm32l5)]
-            w.set_pllsrc(pll.source);
-            write_fields!(w);
-        }),
-        #[cfg(any(stm32l47x, stm32l48x, stm32l49x, stm32l4ax, rcc_l4plus, stm32l5))]
-        PllInstance::Pllsai2 => RCC.pllsai2cfgr().write(|w| {
-            #[cfg(any(rcc_l4plus, stm32l5))]
-            w.set_pllm(pll.prediv);
-            #[cfg(stm32l5)]
-            w.set_pllsrc(pll.source);
-            write_fields!(w);
-        }),
-    }
-
-    // Enable PLL
-    pll_enable(instance, true);
-
-    PllOutput { p, q, r }
 }

embassy-stm32/src/rcc/l0l1.rs

@@ -1,205 +0,0 @@
-pub use crate::pac::pwr::vals::Vos as VoltageScale;
-pub use crate::pac::rcc::vals::{
-    Hpre as AHBPrescaler, Msirange as MSIRange, Plldiv as PLLDiv, Pllmul as PLLMul, Ppre as APBPrescaler,
-};
-use crate::pac::rcc::vals::{Pllsrc, Sw};
-#[cfg(crs)]
-use crate::pac::{crs, CRS, SYSCFG};
-use crate::pac::{FLASH, PWR, RCC};
-use crate::rcc::{set_freqs, Clocks};
-use crate::time::Hertz;
-
-/// HSI speed
-pub const HSI_FREQ: Hertz = Hertz(16_000_000);
-
-/// System clock mux source
-#[derive(Clone, Copy)]
-pub enum ClockSrc {
-    MSI(MSIRange),
-    PLL(PLLSource, PLLMul, PLLDiv),
-    HSE(Hertz),
-    HSI,
-}
-
-/// PLL clock input source
-#[derive(Clone, Copy)]
-pub enum PLLSource {
-    HSI,
-    HSE(Hertz),
-}
-
-impl From<PLLSource> for Pllsrc {
-    fn from(val: PLLSource) -> Pllsrc {
-        match val {
-            PLLSource::HSI => Pllsrc::HSI,
-            PLLSource::HSE(_) => Pllsrc::HSE,
-        }
-    }
-}
-
-/// Clocks configutation
-pub struct Config {
-    pub mux: ClockSrc,
-    pub ahb_pre: AHBPrescaler,
-    pub apb1_pre: APBPrescaler,
-    pub apb2_pre: APBPrescaler,
-    #[cfg(crs)]
-    pub enable_hsi48: bool,
-    pub ls: super::LsConfig,
-    pub voltage_scale: VoltageScale,
-}
-
-impl Default for Config {
-    #[inline]
-    fn default() -> Config {
-        Config {
-            mux: ClockSrc::MSI(MSIRange::RANGE5),
-            ahb_pre: AHBPrescaler::DIV1,
-            apb1_pre: APBPrescaler::DIV1,
-            apb2_pre: APBPrescaler::DIV1,
-            #[cfg(crs)]
-            enable_hsi48: false,
-            voltage_scale: VoltageScale::RANGE1,
-            ls: Default::default(),
-        }
-    }
-}
-
-pub(crate) unsafe fn init(config: Config) {
-    // Set voltage scale
-    while PWR.csr().read().vosf() {}
-    PWR.cr().write(|w| w.set_vos(config.voltage_scale));
-    while PWR.csr().read().vosf() {}
-
-    let (sys_clk, sw) = match config.mux {
-        ClockSrc::MSI(range) => {
-            // Set MSI range
-            RCC.icscr().write(|w| w.set_msirange(range));
-
-            // Enable MSI
-            RCC.cr().write(|w| w.set_msion(true));
-            while !RCC.cr().read().msirdy() {}
-
-            let freq = 32_768 * (1 << (range as u8 + 1));
-            (Hertz(freq), Sw::MSI)
-        }
-        ClockSrc::HSI => {
-            // Enable HSI
-            RCC.cr().write(|w| w.set_hsion(true));
-            while !RCC.cr().read().hsirdy() {}
-
-            (HSI_FREQ, Sw::HSI)
-        }
-        ClockSrc::HSE(freq) => {
-            // Enable HSE
-            RCC.cr().write(|w| w.set_hseon(true));
-            while !RCC.cr().read().hserdy() {}
-
-            (freq, Sw::HSE)
-        }
-        ClockSrc::PLL(src, mul, div) => {
-            let freq = match src {
-                PLLSource::HSE(freq) => {
-                    // Enable HSE
-                    RCC.cr().write(|w| w.set_hseon(true));
-                    while !RCC.cr().read().hserdy() {}
-                    freq
-                }
-                PLLSource::HSI => {
-                    // Enable HSI
-                    RCC.cr().write(|w| w.set_hsion(true));
-                    while !RCC.cr().read().hsirdy() {}
-                    HSI_FREQ
-                }
-            };
-
-            // Disable PLL
-            RCC.cr().modify(|w| w.set_pllon(false));
-            while RCC.cr().read().pllrdy() {}
-
-            let freq = freq * mul / div;
-
-            assert!(freq <= Hertz(32_000_000));
-
-            RCC.cfgr().write(move |w| {
-                w.set_pllmul(mul);
-                w.set_plldiv(div);
-                w.set_pllsrc(src.into());
-            });
-
-            // Enable PLL
-            RCC.cr().modify(|w| w.set_pllon(true));
-            while !RCC.cr().read().pllrdy() {}
-
-            (freq, Sw::PLL1_P)
-        }
-    };
-
-    let rtc = config.ls.init();
-
-    let wait_states = match (config.voltage_scale, sys_clk.0) {
-        (VoltageScale::RANGE1, ..=16_000_000) => 0,
-        (VoltageScale::RANGE2, ..=8_000_000) => 0,
-        (VoltageScale::RANGE3, ..=4_200_000) => 0,
-        _ => 1,
-    };
-
-    #[cfg(stm32l1)]
-    FLASH.acr().write(|w| w.set_acc64(true));
-    FLASH.acr().modify(|w| w.set_prften(true));
-    FLASH.acr().modify(|w| w.set_latency(wait_states != 0));
-
-    RCC.cfgr().modify(|w| {
-        w.set_sw(sw);
-        w.set_hpre(config.ahb_pre);
-        w.set_ppre1(config.apb1_pre);
-        w.set_ppre2(config.apb2_pre);
-    });
-
-    let hclk1 = sys_clk / config.ahb_pre;
-    let (pclk1, pclk1_tim) = super::util::calc_pclk(hclk1, config.apb1_pre);
-    let (pclk2, pclk2_tim) = super::util::calc_pclk(hclk1, config.apb2_pre);
-
-    #[cfg(crs)]
-    if config.enable_hsi48 {
-        // Reset CRS peripheral
-        RCC.apb1rstr().modify(|w| w.set_crsrst(true));
-        RCC.apb1rstr().modify(|w| w.set_crsrst(false));
-
-        // Enable CRS peripheral
-        RCC.apb1enr().modify(|w| w.set_crsen(true));
-
-        // Initialize CRS
-        CRS.cfgr().write(|w|
-
-        // Select LSE as synchronization source
-        w.set_syncsrc(crs::vals::Syncsrc::LSE));
-        CRS.cr().modify(|w| {
-            w.set_autotrimen(true);
-            w.set_cen(true);
-        });
-
-        // Enable VREFINT reference for HSI48 oscillator
-        SYSCFG.cfgr3().modify(|w| {
-            w.set_enref_hsi48(true);
-            w.set_en_vrefint(true);
-        });
-
-        // Select HSI48 as USB clock
-        RCC.ccipr().modify(|w| w.set_hsi48msel(true));
-
-        // Enable dedicated USB clock
-        RCC.crrcr().modify(|w| w.set_hsi48on(true));
-        while !RCC.crrcr().read().hsi48rdy() {}
-    }
-
-    set_freqs(Clocks {
-        sys: sys_clk,
-        hclk1,
-        pclk1,
-        pclk2,
-        pclk1_tim,
-        pclk2_tim,
-        rtc,
-    });
-}

embassy-stm32/src/rcc/mod.rs

@@ -9,22 +9,23 @@ mod mco;
 pub use bd::*;
 pub use mco::*;
 
+#[cfg(crs)]
+mod hsi48;
+#[cfg(crs)]
+pub use hsi48::*;
+
 #[cfg_attr(rcc_f0, path = "f0.rs")]
-#[cfg_attr(any(rcc_f1, rcc_f100, rcc_f1cl), path = "f1.rs")]
-#[cfg_attr(rcc_f2, path = "f2.rs")]
-#[cfg_attr(any(rcc_f3, rcc_f3_v2), path = "f3.rs")]
-#[cfg_attr(any(rcc_f4, rcc_f410, rcc_f7), path = "f4f7.rs")]
+#[cfg_attr(any(stm32f1), path = "f1.rs")]
+#[cfg_attr(any(stm32f3), path = "f3.rs")]
+#[cfg_attr(any(stm32f2, stm32f4, stm32f7), path = "f.rs")]
 #[cfg_attr(rcc_c0, path = "c0.rs")]
 #[cfg_attr(rcc_g0, path = "g0.rs")]
 #[cfg_attr(rcc_g4, path = "g4.rs")]
-#[cfg_attr(any(rcc_h5, rcc_h50, rcc_h7, rcc_h7rm0433, rcc_h7ab), path = "h.rs")]
-#[cfg_attr(any(rcc_l0, rcc_l0_v2, rcc_l1), path = "l0l1.rs")]
-#[cfg_attr(any(rcc_l4, rcc_l4plus, rcc_l5, rcc_wl5, rcc_wle, rcc_wb), path = "l4l5.rs")]
+#[cfg_attr(any(stm32h5, stm32h7), path = "h.rs")]
+#[cfg_attr(any(stm32l0, stm32l1, stm32l4, stm32l5, stm32wb, stm32wl), path = "l.rs")]
 #[cfg_attr(rcc_u5, path = "u5.rs")]
 #[cfg_attr(rcc_wba, path = "wba.rs")]
 mod _version;
-#[cfg(feature = "low-power")]
-use core::sync::atomic::{AtomicU32, Ordering};
 
 pub use _version::*;
 
@@ -183,27 +184,16 @@ pub struct Clocks {
 }
 
 #[cfg(feature = "low-power")]
-static CLOCK_REFCOUNT: AtomicU32 = AtomicU32::new(0);
+/// Must be written within a critical section
+///
+/// May be read without a critical section
+pub(crate) static mut REFCOUNT_STOP1: u32 = 0;
 
 #[cfg(feature = "low-power")]
-pub fn low_power_ready() -> bool {
-    // trace!("clock refcount: {}", CLOCK_REFCOUNT.load(Ordering::SeqCst));
-    CLOCK_REFCOUNT.load(Ordering::SeqCst) == 0
-}
-
-#[cfg(feature = "low-power")]
-pub(crate) fn clock_refcount_add(_cs: critical_section::CriticalSection) {
-    // We don't check for overflow because constructing more than u32 peripherals is unlikely
-    let n = CLOCK_REFCOUNT.load(Ordering::Relaxed);
-    CLOCK_REFCOUNT.store(n + 1, Ordering::Relaxed);
-}
-
-#[cfg(feature = "low-power")]
-pub(crate) fn clock_refcount_sub(_cs: critical_section::CriticalSection) {
-    let n = CLOCK_REFCOUNT.load(Ordering::Relaxed);
-    assert!(n != 0);
-    CLOCK_REFCOUNT.store(n - 1, Ordering::Relaxed);
-}
+/// Must be written within a critical section
+///
+/// May be read without a critical section
+pub(crate) static mut REFCOUNT_STOP2: u32 = 0;
 
 /// Frozen clock frequencies
 ///

embassy-stm32/src/rcc/u5.rs

@@ -35,7 +35,7 @@ impl Default for ClockSrc {
 #[derive(Clone, Copy)]
 pub struct PllConfig {
     /// The clock source for the PLL.
-    pub source: PllSrc,
+    pub source: PllSource,
     /// The PLL prescaler.
     ///
     /// The clock speed of the `source` divided by `m` must be between 4 and 16 MHz.
@@ -57,7 +57,7 @@ impl PllConfig {
     /// A configuration for HSI / 1 * 10 / 1 = 160 MHz
     pub const fn hsi_160mhz() -> Self {
         PllConfig {
-            source: PllSrc::HSI,
+            source: PllSource::HSI,
             m: Pllm::DIV1,
             n: Plln::MUL10,
             r: Plldiv::DIV1,
@@ -67,7 +67,7 @@ impl PllConfig {
     /// A configuration for MSIS @ 48 MHz / 3 * 10 / 1 = 160 MHz
     pub const fn msis_160mhz() -> Self {
         PllConfig {
-            source: PllSrc::MSIS(Msirange::RANGE_48MHZ),
+            source: PllSource::MSIS(Msirange::RANGE_48MHZ),
             m: Pllm::DIV3,
             n: Plln::MUL10,
             r: Plldiv::DIV1,
@@ -76,7 +76,7 @@ impl PllConfig {
 }
 
 #[derive(Clone, Copy)]
-pub enum PllSrc {
+pub enum PllSource {
     /// Use an internal medium speed oscillator as the PLL source.
     MSIS(Msirange),
     /// Use the external high speed clock as the system PLL source.
@@ -88,12 +88,12 @@ pub enum PllSrc {
     HSI,
 }
 
-impl Into<Pllsrc> for PllSrc {
+impl Into<Pllsrc> for PllSource {
     fn into(self) -> Pllsrc {
         match self {
-            PllSrc::MSIS(..) => Pllsrc::MSIS,
-            PllSrc::HSE(..) => Pllsrc::HSE,
-            PllSrc::HSI => Pllsrc::HSI,
+            PllSource::MSIS(..) => Pllsrc::MSIS,
+            PllSource::HSE(..) => Pllsrc::HSE,
+            PllSource::HSI => Pllsrc::HSI,
         }
     }
 }
@@ -115,7 +115,7 @@ pub struct Config {
     pub apb1_pre: APBPrescaler,
     pub apb2_pre: APBPrescaler,
     pub apb3_pre: APBPrescaler,
-    pub hsi48: bool,
+    pub hsi48: Option<super::Hsi48Config>,
     /// The voltage range influences the maximum clock frequencies for different parts of the
     /// device. In particular, system clocks exceeding 110 MHz require `RANGE1`, and system clocks
     /// exceeding 55 MHz require at least `RANGE2`.
@@ -189,7 +189,7 @@ impl Default for Config {
             apb1_pre: APBPrescaler::DIV1,
             apb2_pre: APBPrescaler::DIV1,
             apb3_pre: APBPrescaler::DIV1,
-            hsi48: true,
+            hsi48: Some(Default::default()),
             voltage_range: VoltageScale::RANGE3,
             ls: Default::default(),
         }
@@ -216,9 +216,9 @@ pub(crate) unsafe fn init(config: Config) {
         ClockSrc::PLL1_R(pll) => {
             // Configure the PLL source
             let source_clk = match pll.source {
-                PllSrc::MSIS(range) => config.init_msis(range),
-                PllSrc::HSE(hertz) => config.init_hse(hertz),
-                PllSrc::HSI => config.init_hsi(),
+                PllSource::MSIS(range) => config.init_msis(range),
+                PllSource::HSE(hertz) => config.init_hse(hertz),
+                PllSource::HSI => config.init_hsi(),
             };
 
             // Calculate the reference clock, which is the source divided by m
@@ -322,10 +322,7 @@ pub(crate) unsafe fn init(config: Config) {
         }
     };
 
-    if config.hsi48 {
-        RCC.cr().modify(|w| w.set_hsi48on(true));
-        while !RCC.cr().read().hsi48rdy() {}
-    }
+    let _hsi48 = config.hsi48.map(super::init_hsi48);
 
     // The clock source is ready
     // Calculate and set the flash wait states

embassy-stm32/src/rcc/wba.rs

@@ -17,16 +17,16 @@ pub enum ClockSrc {
 }
 
 #[derive(Clone, Copy, Debug)]
-pub enum PllSrc {
+pub enum PllSource {
     HSE(Hertz),
     HSI,
 }
 
-impl Into<Pllsrc> for PllSrc {
+impl Into<Pllsrc> for PllSource {
     fn into(self) -> Pllsrc {
         match self {
-            PllSrc::HSE(..) => Pllsrc::HSE,
-            PllSrc::HSI => Pllsrc::HSI,
+            PllSource::HSE(..) => Pllsrc::HSE,
+            PllSource::HSI => Pllsrc::HSI,
         }
     }
 }

embassy-stm32/src/rtc/datetime.rs

@@ -4,8 +4,64 @@ use core::convert::From;
 #[cfg(feature = "chrono")]
 use chrono::{self, Datelike, NaiveDate, Timelike, Weekday};
 
-use super::byte_to_bcd2;
-use crate::pac::rtc::Rtc;
+#[cfg(any(feature = "defmt", feature = "time"))]
+use crate::peripherals::RTC;
+#[cfg(any(feature = "defmt", feature = "time"))]
+use crate::rtc::sealed::Instance;
+
+/// Represents an instant in time that can be substracted to compute a duration
+pub struct RtcInstant {
+    /// 0..59
+    pub second: u8,
+    /// 0..256
+    pub subsecond: u16,
+}
+
+impl RtcInstant {
+    #[cfg(not(rtc_v2f2))]
+    pub(super) const fn from(second: u8, subsecond: u16) -> Result<Self, Error> {
+        if second > 59 {
+            Err(Error::InvalidSecond)
+        } else {
+            Ok(Self { second, subsecond })
+        }
+    }
+}
+
+#[cfg(feature = "defmt")]
+impl defmt::Format for RtcInstant {
+    fn format(&self, fmt: defmt::Formatter) {
+        defmt::write!(
+            fmt,
+            "{}:{}",
+            self.second,
+            RTC::regs().prer().read().prediv_s() - self.subsecond,
+        )
+    }
+}
+
+#[cfg(feature = "time")]
+impl core::ops::Sub for RtcInstant {
+    type Output = embassy_time::Duration;
+
+    fn sub(self, rhs: Self) -> Self::Output {
+        use embassy_time::{Duration, TICK_HZ};
+
+        let second = if self.second < rhs.second {
+            self.second + 60
+        } else {
+            self.second
+        };
+
+        let psc = RTC::regs().prer().read().prediv_s() as u32;
+
+        let self_ticks = second as u32 * (psc + 1) + (psc - self.subsecond as u32);
+        let other_ticks = rhs.second as u32 * (psc + 1) + (psc - rhs.subsecond as u32);
+        let rtc_ticks = self_ticks - other_ticks;
+
+        Duration::from_ticks(((rtc_ticks * TICK_HZ as u32) / (psc + 1)) as u64)
+    }
+}
 
 /// Errors regarding the [`DateTime`] struct.
 #[derive(Clone, Debug, PartialEq, Eq)]
@@ -32,19 +88,85 @@ pub enum Error {
 /// Structure containing date and time information
 pub struct DateTime {
     /// 0..4095
-    pub year: u16,
+    year: u16,
     /// 1..12, 1 is January
-    pub month: u8,
+    month: u8,
     /// 1..28,29,30,31 depending on month
-    pub day: u8,
+    day: u8,
     ///
-    pub day_of_week: DayOfWeek,
+    day_of_week: DayOfWeek,
     /// 0..23
-    pub hour: u8,
+    hour: u8,
     /// 0..59
-    pub minute: u8,
+    minute: u8,
     /// 0..59
-    pub second: u8,
+    second: u8,
+}
+
+impl DateTime {
+    pub const fn year(&self) -> u16 {
+        self.year
+    }
+
+    pub const fn month(&self) -> u8 {
+        self.month
+    }
+
+    pub const fn day(&self) -> u8 {
+        self.day
+    }
+
+    pub const fn day_of_week(&self) -> DayOfWeek {
+        self.day_of_week
+    }
+
+    pub const fn hour(&self) -> u8 {
+        self.hour
+    }
+
+    pub const fn minute(&self) -> u8 {
+        self.minute
+    }
+
+    pub const fn second(&self) -> u8 {
+        self.second
+    }
+
+    pub fn from(
+        year: u16,
+        month: u8,
+        day: u8,
+        day_of_week: u8,
+        hour: u8,
+        minute: u8,
+        second: u8,
+    ) -> Result<Self, Error> {
+        let day_of_week = day_of_week_from_u8(day_of_week)?;
+
+        if year > 4095 {
+            Err(Error::InvalidYear)
+        } else if month < 1 || month > 12 {
+            Err(Error::InvalidMonth)
+        } else if day < 1 || day > 31 {
+            Err(Error::InvalidDay)
+        } else if hour > 23 {
+            Err(Error::InvalidHour)
+        } else if minute > 59 {
+            Err(Error::InvalidMinute)
+        } else if second > 59 {
+            Err(Error::InvalidSecond)
+        } else {
+            Ok(Self {
+                year,
+                month,
+                day,
+                day_of_week,
+                hour,
+                minute,
+                second,
+            })
+        }
+    }
 }
 
 #[cfg(feature = "chrono")]
@@ -77,13 +199,13 @@ impl From<DateTime> for chrono::NaiveDateTime {
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Ord, PartialOrd, Hash)]
 #[allow(missing_docs)]
 pub enum DayOfWeek {
-    Monday = 0,
-    Tuesday = 1,
-    Wednesday = 2,
-    Thursday = 3,
-    Friday = 4,
-    Saturday = 5,
-    Sunday = 6,
+    Monday = 1,
+    Tuesday = 2,
+    Wednesday = 3,
+    Thursday = 4,
+    Friday = 5,
+    Saturday = 6,
+    Sunday = 7,
 }
 
 #[cfg(feature = "chrono")]
@@ -108,92 +230,19 @@ impl From<DayOfWeek> for chrono::Weekday {
     }
 }
 
-fn day_of_week_from_u8(v: u8) -> Result<DayOfWeek, Error> {
+pub(super) const fn day_of_week_from_u8(v: u8) -> Result<DayOfWeek, Error> {
     Ok(match v {
-        0 => DayOfWeek::Monday,
-        1 => DayOfWeek::Tuesday,
-        2 => DayOfWeek::Wednesday,
-        3 => DayOfWeek::Thursday,
-        4 => DayOfWeek::Friday,
-        5 => DayOfWeek::Saturday,
-        6 => DayOfWeek::Sunday,
+        1 => DayOfWeek::Monday,
+        2 => DayOfWeek::Tuesday,
+        3 => DayOfWeek::Wednesday,
+        4 => DayOfWeek::Thursday,
+        5 => DayOfWeek::Friday,
+        6 => DayOfWeek::Saturday,
+        7 => DayOfWeek::Sunday,
         x => return Err(Error::InvalidDayOfWeek(x)),
     })
 }
 
-pub(super) fn day_of_week_to_u8(dotw: DayOfWeek) -> u8 {
+pub(super) const fn day_of_week_to_u8(dotw: DayOfWeek) -> u8 {
     dotw as u8
 }
-
-pub(super) fn validate_datetime(dt: &DateTime) -> Result<(), Error> {
-    if dt.year > 4095 {
-        Err(Error::InvalidYear)
-    } else if dt.month < 1 || dt.month > 12 {
-        Err(Error::InvalidMonth)
-    } else if dt.day < 1 || dt.day > 31 {
-        Err(Error::InvalidDay)
-    } else if dt.hour > 23 {
-        Err(Error::InvalidHour)
-    } else if dt.minute > 59 {
-        Err(Error::InvalidMinute)
-    } else if dt.second > 59 {
-        Err(Error::InvalidSecond)
-    } else {
-        Ok(())
-    }
-}
-
-pub(super) fn write_date_time(rtc: &Rtc, t: DateTime) {
-    let (ht, hu) = byte_to_bcd2(t.hour as u8);
-    let (mnt, mnu) = byte_to_bcd2(t.minute as u8);
-    let (st, su) = byte_to_bcd2(t.second as u8);
-
-    let (dt, du) = byte_to_bcd2(t.day as u8);
-    let (mt, mu) = byte_to_bcd2(t.month as u8);
-    let yr = t.year as u16;
-    let yr_offset = (yr - 1970_u16) as u8;
-    let (yt, yu) = byte_to_bcd2(yr_offset);
-
-    use crate::pac::rtc::vals::Ampm;
-
-    rtc.tr().write(|w| {
-        w.set_ht(ht);
-        w.set_hu(hu);
-        w.set_mnt(mnt);
-        w.set_mnu(mnu);
-        w.set_st(st);
-        w.set_su(su);
-        w.set_pm(Ampm::AM);
-    });
-
-    rtc.dr().write(|w| {
-        w.set_dt(dt);
-        w.set_du(du);
-        w.set_mt(mt > 0);
-        w.set_mu(mu);
-        w.set_yt(yt);
-        w.set_yu(yu);
-        w.set_wdu(day_of_week_to_u8(t.day_of_week));
-    });
-}
-
-pub(super) fn datetime(
-    year: u16,
-    month: u8,
-    day: u8,
-    day_of_week: u8,
-    hour: u8,
-    minute: u8,
-    second: u8,
-) -> Result<DateTime, Error> {
-    let day_of_week = day_of_week_from_u8(day_of_week)?;
-    Ok(DateTime {
-        year,
-        month,
-        day,
-        day_of_week,
-        hour,
-        minute,
-        second,
-    })
-}

embassy-stm32/src/rtc/mod.rs

@@ -9,7 +9,11 @@ use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
 #[cfg(feature = "low-power")]
 use embassy_sync::blocking_mutex::Mutex;
 
+use self::datetime::day_of_week_to_u8;
+#[cfg(not(rtc_v2f2))]
+use self::datetime::RtcInstant;
 pub use self::datetime::{DateTime, DayOfWeek, Error as DateTimeError};
+use crate::pac::rtc::regs::{Dr, Tr};
 use crate::time::Hertz;
 
 /// refer to AN4759 to compare features of RTC2 and RTC3
@@ -29,113 +33,133 @@ use embassy_hal_internal::Peripheral;
 use crate::peripherals::RTC;
 use crate::rtc::sealed::Instance;
 
+#[allow(dead_code)]
+#[repr(u8)]
+#[derive(Clone, Copy, Debug)]
+pub(crate) enum WakeupPrescaler {
+    Div2 = 2,
+    Div4 = 4,
+    Div8 = 8,
+    Div16 = 16,
+}
+
+#[cfg(any(stm32wb, stm32f4, stm32l0, stm32g4))]
+impl From<WakeupPrescaler> for crate::pac::rtc::vals::Wucksel {
+    fn from(val: WakeupPrescaler) -> Self {
+        use crate::pac::rtc::vals::Wucksel;
+
+        match val {
+            WakeupPrescaler::Div2 => Wucksel::DIV2,
+            WakeupPrescaler::Div4 => Wucksel::DIV4,
+            WakeupPrescaler::Div8 => Wucksel::DIV8,
+            WakeupPrescaler::Div16 => Wucksel::DIV16,
+        }
+    }
+}
+
+#[cfg(any(stm32wb, stm32f4, stm32l0, stm32g4))]
+impl From<crate::pac::rtc::vals::Wucksel> for WakeupPrescaler {
+    fn from(val: crate::pac::rtc::vals::Wucksel) -> Self {
+        use crate::pac::rtc::vals::Wucksel;
+
+        match val {
+            Wucksel::DIV2 => WakeupPrescaler::Div2,
+            Wucksel::DIV4 => WakeupPrescaler::Div4,
+            Wucksel::DIV8 => WakeupPrescaler::Div8,
+            Wucksel::DIV16 => WakeupPrescaler::Div16,
+            _ => unreachable!(),
+        }
+    }
+}
+
+#[cfg(feature = "low-power")]
+impl WakeupPrescaler {
+    pub fn compute_min(val: u32) -> Self {
+        *[
+            WakeupPrescaler::Div2,
+            WakeupPrescaler::Div4,
+            WakeupPrescaler::Div8,
+            WakeupPrescaler::Div16,
+        ]
+        .iter()
+        .skip_while(|psc| **psc as u32 <= val)
+        .next()
+        .unwrap_or(&WakeupPrescaler::Div16)
+    }
+}
+
 /// Errors that can occur on methods on [RtcClock]
+#[non_exhaustive]
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub enum RtcError {
     /// An invalid DateTime was given or stored on the hardware.
     InvalidDateTime(DateTimeError),
 
+    /// The current time could not be read
+    ReadFailure,
+
     /// The RTC clock is not running
     NotRunning,
 }
 
-#[cfg(feature = "low-power")]
-/// Represents an instant in time that can be substracted to compute a duration
-struct RtcInstant {
-    second: u8,
-    subsecond: u16,
-}
-
-#[cfg(all(feature = "low-power", feature = "defmt"))]
-impl defmt::Format for RtcInstant {
-    fn format(&self, fmt: defmt::Formatter) {
-        defmt::write!(
-            fmt,
-            "{}:{}",
-            self.second,
-            RTC::regs().prer().read().prediv_s() - self.subsecond,
-        )
-    }
-}
-
-#[cfg(feature = "low-power")]
-impl core::ops::Sub for RtcInstant {
-    type Output = embassy_time::Duration;
-
-    fn sub(self, rhs: Self) -> Self::Output {
-        use embassy_time::{Duration, TICK_HZ};
-
-        let second = if self.second < rhs.second {
-            self.second + 60
-        } else {
-            self.second
-        };
-
-        let psc = RTC::regs().prer().read().prediv_s() as u32;
-
-        let self_ticks = second as u32 * (psc + 1) + (psc - self.subsecond as u32);
-        let other_ticks = rhs.second as u32 * (psc + 1) + (psc - rhs.subsecond as u32);
-        let rtc_ticks = self_ticks - other_ticks;
-
-        Duration::from_ticks(((rtc_ticks * TICK_HZ as u32) / (psc + 1)) as u64)
-    }
-}
-
 pub struct RtcTimeProvider {
     _private: (),
 }
 
 impl RtcTimeProvider {
+    #[cfg(not(rtc_v2f2))]
+    pub(crate) fn instant(&self) -> Result<RtcInstant, RtcError> {
+        self.read(|_, tr, ss| {
+            let second = bcd2_to_byte((tr.st(), tr.su()));
+
+            RtcInstant::from(second, ss).map_err(RtcError::InvalidDateTime)
+        })
+    }
+
     /// Return the current datetime.
     ///
     /// # Errors
     ///
     /// Will return an `RtcError::InvalidDateTime` if the stored value in the system is not a valid [`DayOfWeek`].
     pub fn now(&self) -> Result<DateTime, RtcError> {
-        // For RM0433 we use BYPSHAD=1 to work around errata ES0392 2.19.1
-        #[cfg(rcc_h7rm0433)]
-        loop {
-            let r = RTC::regs();
-            let ss = r.ssr().read().ss();
-            let dr = r.dr().read();
-            let tr = r.tr().read();
-
-            // If an RTCCLK edge occurs during read we may see inconsistent values
-            // so read ssr again and see if it has changed. (see RM0433 Rev 7 46.3.9)
-            let ss_after = r.ssr().read().ss();
-            if ss == ss_after {
-                let second = bcd2_to_byte((tr.st(), tr.su()));
-                let minute = bcd2_to_byte((tr.mnt(), tr.mnu()));
-                let hour = bcd2_to_byte((tr.ht(), tr.hu()));
-
-                let weekday = dr.wdu();
-                let day = bcd2_to_byte((dr.dt(), dr.du()));
-                let month = bcd2_to_byte((dr.mt() as u8, dr.mu()));
-                let year = bcd2_to_byte((dr.yt(), dr.yu())) as u16 + 1970_u16;
-
-                return self::datetime::datetime(year, month, day, weekday, hour, minute, second)
-                    .map_err(RtcError::InvalidDateTime);
-            }
-        }
-
-        #[cfg(not(rcc_h7rm0433))]
-        {
-            let r = RTC::regs();
-            let tr = r.tr().read();
+        self.read(|dr, tr, _| {
             let second = bcd2_to_byte((tr.st(), tr.su()));
             let minute = bcd2_to_byte((tr.mnt(), tr.mnu()));
             let hour = bcd2_to_byte((tr.ht(), tr.hu()));
-            // Reading either RTC_SSR or RTC_TR locks the values in the higher-order
-            // calendar shadow registers until RTC_DR is read.
-            let dr = r.dr().read();
 
             let weekday = dr.wdu();
             let day = bcd2_to_byte((dr.dt(), dr.du()));
             let month = bcd2_to_byte((dr.mt() as u8, dr.mu()));
             let year = bcd2_to_byte((dr.yt(), dr.yu())) as u16 + 1970_u16;
 
-            self::datetime::datetime(year, month, day, weekday, hour, minute, second).map_err(RtcError::InvalidDateTime)
+            DateTime::from(year, month, day, weekday, hour, minute, second).map_err(RtcError::InvalidDateTime)
+        })
+    }
+
+    fn read<R>(&self, mut f: impl FnMut(Dr, Tr, u16) -> Result<R, RtcError>) -> Result<R, RtcError> {
+        let r = RTC::regs();
+
+        #[cfg(not(rtc_v2f2))]
+        let read_ss = || r.ssr().read().ss();
+        #[cfg(rtc_v2f2)]
+        let read_ss = || 0;
+
+        let mut ss = read_ss();
+        for _ in 0..5 {
+            let tr = r.tr().read();
+            let dr = r.dr().read();
+            let ss_after = read_ss();
+
+            // If an RTCCLK edge occurs during read we may see inconsistent values
+            // so read ssr again and see if it has changed. (see RM0433 Rev 7 46.3.9)
+            if ss == ss_after {
+                return f(dr, tr, ss.try_into().unwrap());
+            } else {
+                ss = ss_after
+            }
         }
+
+        return Err(RtcError::ReadFailure);
     }
 }
 
@@ -184,11 +208,7 @@ impl Default for RtcCalibrationCyclePeriod {
 impl Rtc {
     pub fn new(_rtc: impl Peripheral<P = RTC>, rtc_config: RtcConfig) -> Self {
         #[cfg(not(any(stm32l0, stm32f3, stm32l1, stm32f0, stm32f2)))]
-        critical_section::with(|cs| {
-            <RTC as crate::rcc::sealed::RccPeripheral>::enable_and_reset_with_cs(cs);
-            #[cfg(feature = "low-power")]
-            crate::rcc::clock_refcount_sub(cs);
-        });
+        <RTC as crate::rcc::sealed::RccPeripheral>::enable_and_reset();
 
         let mut this = Self {
             #[cfg(feature = "low-power")]
@@ -203,6 +223,14 @@ impl Rtc {
 
         this.configure(async_psc, sync_psc);
 
+        // Wait for the clock to update after initialization
+        #[cfg(not(rtc_v2f2))]
+        {
+            let now = this.instant().unwrap();
+
+            while this.instant().unwrap().subsecond == now.subsecond {}
+        }
+
         this
     }
 
@@ -222,24 +250,47 @@ impl Rtc {
     ///
     /// Will return `RtcError::InvalidDateTime` if the datetime is not a valid range.
     pub fn set_datetime(&mut self, t: DateTime) -> Result<(), RtcError> {
-        self::datetime::validate_datetime(&t).map_err(RtcError::InvalidDateTime)?;
-        self.write(true, |rtc| self::datetime::write_date_time(rtc, t));
+        self.write(true, |rtc| {
+            let (ht, hu) = byte_to_bcd2(t.hour() as u8);
+            let (mnt, mnu) = byte_to_bcd2(t.minute() as u8);
+            let (st, su) = byte_to_bcd2(t.second() as u8);
+
+            let (dt, du) = byte_to_bcd2(t.day() as u8);
+            let (mt, mu) = byte_to_bcd2(t.month() as u8);
+            let yr = t.year() as u16;
+            let yr_offset = (yr - 1970_u16) as u8;
+            let (yt, yu) = byte_to_bcd2(yr_offset);
+
+            use crate::pac::rtc::vals::Ampm;
+
+            rtc.tr().write(|w| {
+                w.set_ht(ht);
+                w.set_hu(hu);
+                w.set_mnt(mnt);
+                w.set_mnu(mnu);
+                w.set_st(st);
+                w.set_su(su);
+                w.set_pm(Ampm::AM);
+            });
+
+            rtc.dr().write(|w| {
+                w.set_dt(dt);
+                w.set_du(du);
+                w.set_mt(mt > 0);
+                w.set_mu(mu);
+                w.set_yt(yt);
+                w.set_yu(yu);
+                w.set_wdu(day_of_week_to_u8(t.day_of_week()));
+            });
+        });
 
         Ok(())
     }
 
-    #[cfg(feature = "low-power")]
+    #[cfg(not(rtc_v2f2))]
     /// Return the current instant.
-    fn instant(&self) -> RtcInstant {
-        let r = RTC::regs();
-        let tr = r.tr().read();
-        let subsecond = r.ssr().read().ss();
-        let second = bcd2_to_byte((tr.st(), tr.su()));
-
-        // Unlock the registers
-        r.dr().read();
-
-        RtcInstant { second, subsecond }
+    fn instant(&self) -> Result<RtcInstant, RtcError> {
+        self.time_provider().instant()
     }
 
     /// Return the current datetime.
@@ -281,6 +332,114 @@ impl Rtc {
     pub fn write_backup_register(&self, register: usize, value: u32) {
         RTC::write_backup_register(&RTC::regs(), register, value)
     }
+
+    #[cfg(feature = "low-power")]
+    /// start the wakeup alarm and wtih a duration that is as close to but less than
+    /// the requested duration, and record the instant the wakeup alarm was started
+    pub(crate) fn start_wakeup_alarm(
+        &self,
+        requested_duration: embassy_time::Duration,
+        cs: critical_section::CriticalSection,
+    ) {
+        use embassy_time::{Duration, TICK_HZ};
+
+        #[cfg(any(rtc_v3, rtc_v3u5))]
+        use crate::pac::rtc::vals::Calrf;
+
+        // Panic if the rcc mod knows we're not using low-power rtc
+        #[cfg(any(rcc_wb, rcc_f4, rcc_f410))]
+        unsafe { crate::rcc::get_freqs() }.rtc.unwrap();
+
+        let requested_duration = requested_duration.as_ticks().clamp(0, u32::MAX as u64);
+        let rtc_hz = Self::frequency().0 as u64;
+        let rtc_ticks = requested_duration * rtc_hz / TICK_HZ;
+        let prescaler = WakeupPrescaler::compute_min((rtc_ticks / u16::MAX as u64) as u32);
+
+        // adjust the rtc ticks to the prescaler and subtract one rtc tick
+        let rtc_ticks = rtc_ticks / prescaler as u64;
+        let rtc_ticks = rtc_ticks.clamp(0, (u16::MAX - 1) as u64).saturating_sub(1) as u16;
+
+        self.write(false, |regs| {
+            regs.cr().modify(|w| w.set_wute(false));
+
+            #[cfg(any(
+                rtc_v2f0, rtc_v2f2, rtc_v2f3, rtc_v2f4, rtc_v2f7, rtc_v2h7, rtc_v2l0, rtc_v2l1, rtc_v2l4, rtc_v2wb
+            ))]
+            {
+                regs.isr().modify(|w| w.set_wutf(false));
+                while !regs.isr().read().wutwf() {}
+            }
+
+            #[cfg(any(rtc_v3, rtc_v3u5))]
+            {
+                regs.scr().write(|w| w.set_cwutf(Calrf::CLEAR));
+                while !regs.icsr().read().wutwf() {}
+            }
+
+            regs.cr().modify(|w| w.set_wucksel(prescaler.into()));
+            regs.wutr().write(|w| w.set_wut(rtc_ticks));
+            regs.cr().modify(|w| w.set_wute(true));
+            regs.cr().modify(|w| w.set_wutie(true));
+        });
+
+        let instant = self.instant().unwrap();
+        trace!(
+            "rtc: start wakeup alarm for {} ms (psc: {}, ticks: {}) at {}",
+            Duration::from_ticks(rtc_ticks as u64 * TICK_HZ * prescaler as u64 / rtc_hz).as_millis(),
+            prescaler as u32,
+            rtc_ticks,
+            instant,
+        );
+
+        assert!(self.stop_time.borrow(cs).replace(Some(instant)).is_none())
+    }
+
+    #[cfg(feature = "low-power")]
+    /// stop the wakeup alarm and return the time elapsed since `start_wakeup_alarm`
+    /// was called, otherwise none
+    pub(crate) fn stop_wakeup_alarm(&self, cs: critical_section::CriticalSection) -> Option<embassy_time::Duration> {
+        use crate::interrupt::typelevel::Interrupt;
+        #[cfg(any(rtc_v3, rtc_v3u5))]
+        use crate::pac::rtc::vals::Calrf;
+
+        let instant = self.instant().unwrap();
+        if RTC::regs().cr().read().wute() {
+            trace!("rtc: stop wakeup alarm at {}", instant);
+
+            self.write(false, |regs| {
+                regs.cr().modify(|w| w.set_wutie(false));
+                regs.cr().modify(|w| w.set_wute(false));
+
+                #[cfg(any(
+                    rtc_v2f0, rtc_v2f2, rtc_v2f3, rtc_v2f4, rtc_v2f7, rtc_v2h7, rtc_v2l0, rtc_v2l1, rtc_v2l4, rtc_v2wb
+                ))]
+                regs.isr().modify(|w| w.set_wutf(false));
+
+                #[cfg(any(rtc_v3, rtc_v3u5))]
+                regs.scr().write(|w| w.set_cwutf(Calrf::CLEAR));
+
+                crate::pac::EXTI
+                    .pr(0)
+                    .modify(|w| w.set_line(RTC::EXTI_WAKEUP_LINE, true));
+
+                <RTC as crate::rtc::sealed::Instance>::WakeupInterrupt::unpend();
+            });
+        }
+
+        self.stop_time.borrow(cs).take().map(|stop_time| instant - stop_time)
+    }
+
+    #[cfg(feature = "low-power")]
+    pub(crate) fn enable_wakeup_line(&self) {
+        use crate::interrupt::typelevel::Interrupt;
+        use crate::pac::EXTI;
+
+        <RTC as crate::rtc::sealed::Instance>::WakeupInterrupt::unpend();
+        unsafe { <RTC as crate::rtc::sealed::Instance>::WakeupInterrupt::enable() };
+
+        EXTI.rtsr(0).modify(|w| w.set_line(RTC::EXTI_WAKEUP_LINE, true));
+        EXTI.imr(0).modify(|w| w.set_line(RTC::EXTI_WAKEUP_LINE, true));
+    }
 }
 
 pub(crate) fn byte_to_bcd2(byte: u8) -> (u8, u8) {

embassy-stm32/src/rtc/v2.rs

@@ -6,159 +6,20 @@ use crate::peripherals::RTC;
 use crate::rtc::sealed::Instance;
 
 #[allow(dead_code)]
-#[repr(u8)]
-#[derive(Clone, Copy, Debug)]
-pub(crate) enum WakeupPrescaler {
-    Div2 = 2,
-    Div4 = 4,
-    Div8 = 8,
-    Div16 = 16,
-}
-
-#[cfg(any(stm32wb, stm32f4, stm32l0))]
-impl From<WakeupPrescaler> for crate::pac::rtc::vals::Wucksel {
-    fn from(val: WakeupPrescaler) -> Self {
-        use crate::pac::rtc::vals::Wucksel;
-
-        match val {
-            WakeupPrescaler::Div2 => Wucksel::DIV2,
-            WakeupPrescaler::Div4 => Wucksel::DIV4,
-            WakeupPrescaler::Div8 => Wucksel::DIV8,
-            WakeupPrescaler::Div16 => Wucksel::DIV16,
-        }
-    }
-}
-
-#[cfg(any(stm32wb, stm32f4, stm32l0))]
-impl From<crate::pac::rtc::vals::Wucksel> for WakeupPrescaler {
-    fn from(val: crate::pac::rtc::vals::Wucksel) -> Self {
-        use crate::pac::rtc::vals::Wucksel;
-
-        match val {
-            Wucksel::DIV2 => WakeupPrescaler::Div2,
-            Wucksel::DIV4 => WakeupPrescaler::Div4,
-            Wucksel::DIV8 => WakeupPrescaler::Div8,
-            Wucksel::DIV16 => WakeupPrescaler::Div16,
-            _ => unreachable!(),
-        }
-    }
-}
-
-#[allow(dead_code)]
-impl WakeupPrescaler {
-    pub fn compute_min(val: u32) -> Self {
-        *[
-            WakeupPrescaler::Div2,
-            WakeupPrescaler::Div4,
-            WakeupPrescaler::Div8,
-            WakeupPrescaler::Div16,
-        ]
-        .iter()
-        .skip_while(|psc| **psc as u32 <= val)
-        .next()
-        .unwrap_or(&WakeupPrescaler::Div16)
-    }
-}
-
 impl super::Rtc {
-    #[cfg(feature = "low-power")]
-    /// start the wakeup alarm and wtih a duration that is as close to but less than
-    /// the requested duration, and record the instant the wakeup alarm was started
-    pub(crate) fn start_wakeup_alarm(
-        &self,
-        requested_duration: embassy_time::Duration,
-        cs: critical_section::CriticalSection,
-    ) {
-        use embassy_time::{Duration, TICK_HZ};
-
-        // Panic if the rcc mod knows we're not using low-power rtc
-        #[cfg(any(rcc_wb, rcc_f4, rcc_f410))]
-        unsafe { crate::rcc::get_freqs() }.rtc.unwrap();
-
-        let requested_duration = requested_duration.as_ticks().clamp(0, u32::MAX as u64);
-        let rtc_hz = Self::frequency().0 as u64;
-        let rtc_ticks = requested_duration * rtc_hz / TICK_HZ;
-        let prescaler = WakeupPrescaler::compute_min((rtc_ticks / u16::MAX as u64) as u32);
-
-        // adjust the rtc ticks to the prescaler and subtract one rtc tick
-        let rtc_ticks = rtc_ticks / prescaler as u64;
-        let rtc_ticks = rtc_ticks.clamp(0, (u16::MAX - 1) as u64).saturating_sub(1) as u16;
-
-        self.write(false, |regs| {
-            regs.cr().modify(|w| w.set_wute(false));
-            regs.isr().modify(|w| w.set_wutf(false));
-            while !regs.isr().read().wutwf() {}
-
-            regs.cr().modify(|w| w.set_wucksel(prescaler.into()));
-            regs.wutr().write(|w| w.set_wut(rtc_ticks));
-            regs.cr().modify(|w| w.set_wute(true));
-            regs.cr().modify(|w| w.set_wutie(true));
-        });
-
-        trace!(
-            "rtc: start wakeup alarm for {} ms (psc: {}, ticks: {}) at {}",
-            Duration::from_ticks(rtc_ticks as u64 * TICK_HZ * prescaler as u64 / rtc_hz).as_millis(),
-            prescaler as u32,
-            rtc_ticks,
-            self.instant(),
-        );
-
-        assert!(self.stop_time.borrow(cs).replace(Some(self.instant())).is_none())
-    }
-
-    #[cfg(feature = "low-power")]
-    /// stop the wakeup alarm and return the time elapsed since `start_wakeup_alarm`
-    /// was called, otherwise none
-    pub(crate) fn stop_wakeup_alarm(&self, cs: critical_section::CriticalSection) -> Option<embassy_time::Duration> {
-        use crate::interrupt::typelevel::Interrupt;
-
-        if RTC::regs().cr().read().wute() {
-            trace!("rtc: stop wakeup alarm at {}", self.instant());
-
-            self.write(false, |regs| {
-                regs.cr().modify(|w| w.set_wutie(false));
-                regs.cr().modify(|w| w.set_wute(false));
-                regs.isr().modify(|w| w.set_wutf(false));
-
-                crate::pac::EXTI
-                    .pr(0)
-                    .modify(|w| w.set_line(RTC::EXTI_WAKEUP_LINE, true));
-
-                <RTC as crate::rtc::sealed::Instance>::WakeupInterrupt::unpend();
-            });
-        }
-
-        self.stop_time
-            .borrow(cs)
-            .take()
-            .map(|stop_time| self.instant() - stop_time)
-    }
-
-    #[cfg(feature = "low-power")]
-    pub(crate) fn enable_wakeup_line(&self) {
-        use crate::interrupt::typelevel::Interrupt;
-        use crate::pac::EXTI;
-
-        <RTC as crate::rtc::sealed::Instance>::WakeupInterrupt::unpend();
-        unsafe { <RTC as crate::rtc::sealed::Instance>::WakeupInterrupt::enable() };
-
-        EXTI.rtsr(0).modify(|w| w.set_line(RTC::EXTI_WAKEUP_LINE, true));
-        EXTI.imr(0).modify(|w| w.set_line(RTC::EXTI_WAKEUP_LINE, true));
-    }
-
     /// Applies the RTC config
     /// It this changes the RTC clock source the time will be reset
     pub(super) fn configure(&mut self, async_psc: u8, sync_psc: u16) {
         self.write(true, |rtc| {
             rtc.cr().modify(|w| {
+                #[cfg(not(rtc_v2f2))]
+                w.set_bypshad(true);
                 #[cfg(rtc_v2f2)]
                 w.set_fmt(false);
                 #[cfg(not(rtc_v2f2))]
                 w.set_fmt(stm32_metapac::rtc::vals::Fmt::TWENTY_FOUR_HOUR);
                 w.set_osel(Osel::DISABLED);
                 w.set_pol(Pol::HIGH);
-                #[cfg(rcc_h7rm0433)]
-                w.set_bypshad(true);
             });
 
             rtc.prer().modify(|w| {

embassy-stm32/src/rtc/v3.rs

@@ -11,6 +11,7 @@ impl super::Rtc {
     pub(super) fn configure(&mut self, async_psc: u8, sync_psc: u16) {
         self.write(true, |rtc| {
             rtc.cr().modify(|w| {
+                w.set_bypshad(true);
                 w.set_fmt(Fmt::TWENTYFOURHOUR);
                 w.set_osel(Osel::DISABLED);
                 w.set_pol(Pol::HIGH);
@@ -94,7 +95,7 @@ impl super::Rtc {
         })
     }
 
-    pub(super) fn write<F, R>(&mut self, init_mode: bool, f: F) -> R
+    pub(super) fn write<F, R>(&self, init_mode: bool, f: F) -> R
     where
         F: FnOnce(&crate::pac::rtc::Rtc) -> R,
     {
@@ -128,6 +129,12 @@ impl super::Rtc {
 impl sealed::Instance for crate::peripherals::RTC {
     const BACKUP_REGISTER_COUNT: usize = 32;
 
+    #[cfg(all(feature = "low-power", stm32g4))]
+    const EXTI_WAKEUP_LINE: usize = 20;
+
+    #[cfg(all(feature = "low-power", stm32g4))]
+    type WakeupInterrupt = crate::interrupt::typelevel::RTC_WKUP;
+
     fn read_backup_register(_rtc: &Rtc, register: usize) -> Option<u32> {
         #[allow(clippy::if_same_then_else)]
         if register < Self::BACKUP_REGISTER_COUNT {

embassy-stm32/src/time_driver.rs

@@ -345,6 +345,10 @@ impl RtcDriver {
         });
     }
 
+    #[cfg(feature = "low-power")]
+    /// The minimum pause time beyond which the executor will enter a low-power state.
+    pub(crate) const MIN_STOP_PAUSE: embassy_time::Duration = embassy_time::Duration::from_millis(250);
+
     #[cfg(feature = "low-power")]
     /// Pause the timer if ready; return err if not
     pub(crate) fn pause_time(&self) -> Result<(), ()> {
@@ -357,7 +361,7 @@ impl RtcDriver {
             self.stop_wakeup_alarm(cs);
 
             let time_until_next_alarm = self.time_until_next_alarm(cs);
-            if time_until_next_alarm < embassy_time::Duration::from_millis(250) {
+            if time_until_next_alarm < Self::MIN_STOP_PAUSE {
                 Err(())
             } else {
                 self.rtc

embassy-stm32/src/usart/buffered.rs

@@ -116,28 +116,28 @@ pub struct BufferedUartRx<'d, T: BasicInstance> {
 
 impl<'d, T: BasicInstance> SetConfig for BufferedUart<'d, T> {
     type Config = Config;
-    type ConfigError = ();
+    type ConfigError = ConfigError;
 
-    fn set_config(&mut self, config: &Self::Config) -> Result<(), ()> {
-        self.set_config(config).map_err(|_| ())
+    fn set_config(&mut self, config: &Self::Config) -> Result<(), Self::ConfigError> {
+        self.set_config(config)
     }
 }
 
 impl<'d, T: BasicInstance> SetConfig for BufferedUartRx<'d, T> {
     type Config = Config;
-    type ConfigError = ();
+    type ConfigError = ConfigError;
 
-    fn set_config(&mut self, config: &Self::Config) -> Result<(), ()> {
-        self.set_config(config).map_err(|_| ())
+    fn set_config(&mut self, config: &Self::Config) -> Result<(), Self::ConfigError> {
+        self.set_config(config)
     }
 }
 
 impl<'d, T: BasicInstance> SetConfig for BufferedUartTx<'d, T> {
     type Config = Config;
-    type ConfigError = ();
+    type ConfigError = ConfigError;
 
-    fn set_config(&mut self, config: &Self::Config) -> Result<(), ()> {
-        self.set_config(config).map_err(|_| ())
+    fn set_config(&mut self, config: &Self::Config) -> Result<(), Self::ConfigError> {
+        self.set_config(config)
     }
 }
 
@@ -233,9 +233,6 @@ impl<'d, T: BasicInstance> BufferedUart<'d, T> {
         configure(r, &config, T::frequency(), T::KIND, true, true)?;
 
         r.cr1().modify(|w| {
-            #[cfg(lpuart_v2)]
-            w.set_fifoen(true);
-
             w.set_rxneie(true);
             w.set_idleie(true);
         });
@@ -254,7 +251,14 @@ impl<'d, T: BasicInstance> BufferedUart<'d, T> {
     }
 
     pub fn set_config(&mut self, config: &Config) -> Result<(), ConfigError> {
-        reconfigure::<T>(config)
+        reconfigure::<T>(config)?;
+
+        T::regs().cr1().modify(|w| {
+            w.set_rxneie(true);
+            w.set_idleie(true);
+        });
+
+        Ok(())
     }
 }
 
@@ -334,7 +338,14 @@ impl<'d, T: BasicInstance> BufferedUartRx<'d, T> {
     }
 
     pub fn set_config(&mut self, config: &Config) -> Result<(), ConfigError> {
-        reconfigure::<T>(config)
+        reconfigure::<T>(config)?;
+
+        T::regs().cr1().modify(|w| {
+            w.set_rxneie(true);
+            w.set_idleie(true);
+        });
+
+        Ok(())
     }
 }
 
@@ -408,7 +419,14 @@ impl<'d, T: BasicInstance> BufferedUartTx<'d, T> {
     }
 
     pub fn set_config(&mut self, config: &Config) -> Result<(), ConfigError> {
-        reconfigure::<T>(config)
+        reconfigure::<T>(config)?;
+
+        T::regs().cr1().modify(|w| {
+            w.set_rxneie(true);
+            w.set_idleie(true);
+        });
+
+        Ok(())
     }
 }
 

embassy-stm32/src/usart/mod.rs

@@ -108,6 +108,7 @@ pub enum StopBits {
 pub enum ConfigError {
     BaudrateTooLow,
     BaudrateTooHigh,
+    RxOrTxNotEnabled,
 }
 
 #[non_exhaustive]
@@ -181,11 +182,11 @@ pub struct Uart<'d, T: BasicInstance, TxDma = NoDma, RxDma = NoDma> {
 
 impl<'d, T: BasicInstance, TxDma, RxDma> SetConfig for Uart<'d, T, TxDma, RxDma> {
     type Config = Config;
-    type ConfigError = ();
+    type ConfigError = ConfigError;
 
-    fn set_config(&mut self, config: &Self::Config) -> Result<(), ()> {
-        self.tx.set_config(config).map_err(|_| ())?;
-        self.rx.set_config(config).map_err(|_| ())
+    fn set_config(&mut self, config: &Self::Config) -> Result<(), Self::ConfigError> {
+        self.tx.set_config(config)?;
+        self.rx.set_config(config)
     }
 }
 
@@ -196,10 +197,10 @@ pub struct UartTx<'d, T: BasicInstance, TxDma = NoDma> {
 
 impl<'d, T: BasicInstance, TxDma> SetConfig for UartTx<'d, T, TxDma> {
     type Config = Config;
-    type ConfigError = ();
+    type ConfigError = ConfigError;
 
-    fn set_config(&mut self, config: &Self::Config) -> Result<(), ()> {
-        self.set_config(config).map_err(|_| ())
+    fn set_config(&mut self, config: &Self::Config) -> Result<(), Self::ConfigError> {
+        self.set_config(config)
     }
 }
 
@@ -213,10 +214,10 @@ pub struct UartRx<'d, T: BasicInstance, RxDma = NoDma> {
 
 impl<'d, T: BasicInstance, RxDma> SetConfig for UartRx<'d, T, RxDma> {
     type Config = Config;
-    type ConfigError = ();
+    type ConfigError = ConfigError;
 
-    fn set_config(&mut self, config: &Self::Config) -> Result<(), ()> {
-        self.set_config(config).map_err(|_| ())
+    fn set_config(&mut self, config: &Self::Config) -> Result<(), Self::ConfigError> {
+        self.set_config(config)
     }
 }
 
@@ -866,7 +867,7 @@ fn configure(
     enable_tx: bool,
 ) -> Result<(), ConfigError> {
     if !enable_rx && !enable_tx {
-        panic!("USART: At least one of RX or TX should be enabled");
+        return Err(ConfigError::RxOrTxNotEnabled);
     }
 
     #[cfg(not(usart_v4))]
@@ -909,6 +910,11 @@ fn configure(
         brr + rounding
     }
 
+    // UART must be disabled during configuration.
+    r.cr1().modify(|w| {
+        w.set_ue(false);
+    });
+
     #[cfg(not(usart_v1))]
     let mut over8 = false;
     let mut found_brr = None;
@@ -968,6 +974,12 @@ fn configure(
         #[cfg(any(usart_v3, usart_v4))]
         w.set_swap(config.swap_rx_tx);
     });
+
+    #[cfg(not(usart_v1))]
+    r.cr3().modify(|w| {
+        w.set_onebit(config.assume_noise_free);
+    });
+
     r.cr1().write(|w| {
         // enable uart
         w.set_ue(true);
@@ -976,6 +988,7 @@ fn configure(
         // enable receiver
         w.set_re(enable_rx);
         // configure word size
+        // if using odd or even parity it must be configured to 9bits
         w.set_m0(if config.parity != Parity::ParityNone {
             vals::M0::BIT9
         } else {
@@ -994,11 +1007,6 @@ fn configure(
         w.set_fifoen(true);
     });
 
-    #[cfg(not(usart_v1))]
-    r.cr3().modify(|w| {
-        w.set_onebit(config.assume_noise_free);
-    });
-
     Ok(())
 }
 

embassy-stm32/src/usart/ringbuffered.rs

@@ -18,10 +18,10 @@ pub struct RingBufferedUartRx<'d, T: BasicInstance, RxDma: super::RxDma<T>> {
 
 impl<'d, T: BasicInstance, RxDma: super::RxDma<T>> SetConfig for RingBufferedUartRx<'d, T, RxDma> {
     type Config = Config;
-    type ConfigError = ();
+    type ConfigError = ConfigError;
 
-    fn set_config(&mut self, config: &Self::Config) -> Result<(), ()> {
-        self.set_config(config).map_err(|_| ())
+    fn set_config(&mut self, config: &Self::Config) -> Result<(), Self::ConfigError> {
+        self.set_config(config)
     }
 }
 

embassy-stm32/src/usb_otg/usb.rs

@@ -40,6 +40,7 @@ impl<T: Instance> interrupt::typelevel::Handler<T::Interrupt> for InterruptHandl
         // Handle RX
         while r.gintsts().read().rxflvl() {
             let status = r.grxstsp().read();
+            trace!("=== status {:08x}", status.0);
             let ep_num = status.epnum() as usize;
             let len = status.bcnt() as usize;
 
@@ -51,6 +52,15 @@ impl<T: Instance> interrupt::typelevel::Handler<T::Interrupt> for InterruptHandl
                     assert!(len == 8, "invalid SETUP packet length={}", len);
                     assert!(ep_num == 0, "invalid SETUP packet endpoint={}", ep_num);
 
+                    // flushing TX if something stuck in control endpoint
+                    if r.dieptsiz(ep_num).read().pktcnt() != 0 {
+                        r.grstctl().modify(|w| {
+                            w.set_txfnum(ep_num as _);
+                            w.set_txfflsh(true);
+                        });
+                        while r.grstctl().read().txfflsh() {}
+                    }
+
                     if state.ep0_setup_ready.load(Ordering::Relaxed) == false {
                         // SAFETY: exclusive access ensured by atomic bool
                         let data = unsafe { &mut *state.ep0_setup_data.get() };
@@ -96,6 +106,11 @@ impl<T: Instance> interrupt::typelevel::Handler<T::Interrupt> for InterruptHandl
                 }
                 vals::Pktstsd::SETUP_DATA_DONE => {
                     trace!("SETUP_DATA_DONE ep={}", ep_num);
+
+                    if quirk_setup_late_cnak(r) {
+                        // Clear NAK to indicate we are ready to receive more data
+                        r.doepctl(ep_num).modify(|w| w.set_cnak(true));
+                    }
                 }
                 x => trace!("unknown PKTSTS: {}", x.to_bits()),
             }
@@ -911,11 +926,9 @@ impl<'d, T: Instance> embassy_usb_driver::Bus for Bus<'d, T> {
                 trace!("enumdne");
 
                 let speed = r.dsts().read().enumspd();
-                trace!("  speed={}", speed.to_bits());
-
-                r.gusbcfg().modify(|w| {
-                    w.set_trdt(calculate_trdt(speed, T::frequency()));
-                });
+                let trdt = calculate_trdt(speed, T::frequency());
+                trace!("  speed={} trdt={}", speed.to_bits(), trdt);
+                r.gusbcfg().modify(|w| w.set_trdt(trdt));
 
                 r.gintsts().write(|w| w.set_enumdne(true)); // clear
                 Self::restore_irqs();
@@ -1304,20 +1317,22 @@ impl<'d, T: Instance> embassy_usb_driver::ControlPipe for ControlPipe<'d, T> {
 
             state.ep_out_wakers[0].register(cx.waker());
 
+            let r = T::regs();
+
             if state.ep0_setup_ready.load(Ordering::Relaxed) {
                 let data = unsafe { *state.ep0_setup_data.get() };
                 state.ep0_setup_ready.store(false, Ordering::Release);
 
                 // EP0 should not be controlled by `Bus` so this RMW does not need a critical section
                 // Receive 1 SETUP packet
-                T::regs().doeptsiz(self.ep_out.info.addr.index()).modify(|w| {
+                r.doeptsiz(self.ep_out.info.addr.index()).modify(|w| {
                     w.set_rxdpid_stupcnt(1);
                 });
 
                 // Clear NAK to indicate we are ready to receive more data
-                T::regs().doepctl(self.ep_out.info.addr.index()).modify(|w| {
-                    w.set_cnak(true);
-                });
+                if !quirk_setup_late_cnak(r) {
+                    r.doepctl(self.ep_out.info.addr.index()).modify(|w| w.set_cnak(true));
+                }
 
                 trace!("SETUP received: {:?}", data);
                 Poll::Ready(data)
@@ -1453,3 +1468,7 @@ fn calculate_trdt(speed: vals::Dspd, ahb_freq: Hertz) -> u8 {
         _ => unimplemented!(),
     }
 }
+
+fn quirk_setup_late_cnak(r: crate::pac::otg::Otg) -> bool {
+    r.cid().read().0 & 0xf000 == 0x1000
+}

embassy-sync/CHANGELOG.md

@@ -5,9 +5,14 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## 0.4.0 - 2023-10-31
+
+- Re-add impl_trait_projections
+- switch to `embedded-io 0.6`
+
 ## 0.3.0 - 2023-09-14
 
-- switch to embedded-io 0.5
+- switch to `embedded-io 0.5`
 - add api for polling channels with context
 - standardise fn names on channels
 - add zero-copy channel

embassy-sync/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "embassy-sync"
-version = "0.3.0"
+version = "0.4.0"
 edition = "2021"
 description = "no-std, no-alloc synchronization primitives with async support"
 repository = "https://github.com/embassy-rs/embassy"
@@ -33,7 +33,7 @@ log = { version = "0.4.14", optional = true }
 
 futures-util = { version = "0.3.17", default-features = false }
 critical-section = "1.1"
-heapless = "0.7.5"
+heapless = "0.8"
 cfg-if = "1.0.0"
 embedded-io-async = { version = "0.6.0", optional = true }
 
@@ -45,4 +45,4 @@ futures-util = { version = "0.3.17", features = [ "channel" ] }
 
 # Enable critical-section implementation for std, for tests
 critical-section = { version = "1.1", features = ["std"] }
-static_cell = "1.1"
+static_cell = { version = "2" }

embassy-sync/src/lib.rs

@@ -1,5 +1,6 @@
 #![cfg_attr(not(any(feature = "std", feature = "wasm")), no_std)]
-#![cfg_attr(feature = "nightly", feature(async_fn_in_trait))]
+#![cfg_attr(feature = "nightly", feature(async_fn_in_trait, impl_trait_projections))]
+#![cfg_attr(feature = "nightly", allow(stable_features, unknown_lints, async_fn_in_trait))]
 #![allow(clippy::new_without_default)]
 #![doc = include_str!("../README.md")]
 #![warn(missing_docs)]

embassy-time/CHANGELOG.md

@@ -5,6 +5,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## 0.1.6 - ???
+
+- Added tick rates in multiples of 10 kHz
+
 ## 0.1.5 - 2023-10-16
 
 - Added `links` key to Cargo.toml, to prevent multiple copies of this crate in the same binary.

embassy-time/Cargo.toml

@@ -59,6 +59,9 @@ generic-queue-32 = ["generic-queue"]
 generic-queue-64 = ["generic-queue"]
 generic-queue-128 = ["generic-queue"]
 
+# Create a `MockDriver` that can be manually advanced for testing purposes.
+mock-driver = ["tick-hz-1_000_000"]
+
 # Set the `embassy_time` tick rate.
 #
 # At most 1 `tick-*` feature can be enabled. If none is enabled, a default of 1MHz is used.
@@ -126,6 +129,25 @@ tick-hz-65_536_000 = []
 tick-hz-131_072_000 = []
 tick-hz-262_144_000 = []
 tick-hz-524_288_000 = []
+tick-hz-20_000 = []
+tick-hz-40_000 = []
+tick-hz-80_000 = []
+tick-hz-160_000 = []
+tick-hz-320_000 = []
+tick-hz-640_000 = []
+tick-hz-1_280_000 = []
+tick-hz-2_560_000 = []
+tick-hz-5_120_000 = []
+tick-hz-10_240_000 = []
+tick-hz-20_480_000 = []
+tick-hz-40_960_000 = []
+tick-hz-81_920_000 = []
+tick-hz-163_840_000 = []
+tick-hz-327_680_000 = []
+tick-hz-655_360_000 = []
+tick-hz-1_310_720_000 = []
+tick-hz-2_621_440_000 = []
+tick-hz-5_242_880_000 = []
 tick-hz-2_000_000 = []
 tick-hz-3_000_000 = []
 tick-hz-4_000_000 = []
@@ -226,7 +248,7 @@ embedded-hal-async = { version = "=1.0.0-rc.1", optional = true}
 futures-util = { version = "0.3.17", default-features = false }
 critical-section = "1.1"
 cfg-if = "1.0.0"
-heapless = "0.7"
+heapless = "0.8"
 
 # WASM dependencies
 wasm-bindgen = { version = "0.2.81", optional = true }
@@ -236,4 +258,4 @@ wasm-timer = { version = "0.2.5", optional = true }
 [dev-dependencies]
 serial_test = "0.9"
 critical-section = { version = "1.1", features = ["std"] }
-embassy-executor = { version = "0.3.0", path = "../embassy-executor", features = ["nightly"] }
+embassy-executor = { version = "0.3.3", path = "../embassy-executor", features = ["nightly"] }

embassy-time/gen_tick.py

@@ -13,6 +13,8 @@ for i in range(1, 25):
     ticks.append(2**i)
 for i in range(1, 20):
     ticks.append(2**i * 1000)
+for i in range(1, 20):
+    ticks.append(2**i * 10000)
 for i in range(1, 10):
     ticks.append(2**i * 1000000)
     ticks.append(2**i * 9 // 8 * 1000000)

embassy-time/src/driver_mock.rs

@@ -0,0 +1,68 @@
+use core::cell::Cell;
+
+use critical_section::Mutex as CsMutex;
+
+use crate::driver::{AlarmHandle, Driver};
+use crate::{Duration, Instant};
+
+/// A mock driver that can be manually advanced.
+/// This is useful for testing code that works with [`Instant`] and [`Duration`].
+///
+/// This driver cannot currently be used to test runtime functionality, such as
+/// timers, delays, etc.
+///
+/// # Example
+///
+/// ```ignore
+/// fn has_a_second_passed(reference: Instant) -> bool {
+///     Instant::now().duration_since(reference) >= Duration::from_secs(1)
+/// }
+///
+/// fn test_second_passed() {
+///     let driver = embassy_time::MockDriver::get();
+///     let reference = Instant::now();
+///     assert_eq!(false, has_a_second_passed(reference));
+///     driver.advance(Duration::from_secs(1));
+///     assert_eq!(true, has_a_second_passed(reference));
+/// }
+/// ```
+pub struct MockDriver {
+    now: CsMutex<Cell<Instant>>,
+}
+
+crate::time_driver_impl!(static DRIVER: MockDriver = MockDriver {
+    now: CsMutex::new(Cell::new(Instant::from_ticks(0))),
+});
+
+impl MockDriver {
+    /// Gets a reference to the global mock driver.
+    pub fn get() -> &'static MockDriver {
+        &DRIVER
+    }
+
+    /// Advances the time by the specified [`Duration`].
+    pub fn advance(&self, duration: Duration) {
+        critical_section::with(|cs| {
+            let now = self.now.borrow(cs).get().as_ticks();
+            self.now.borrow(cs).set(Instant::from_ticks(now + duration.as_ticks()));
+        });
+    }
+}
+
+impl Driver for MockDriver {
+    fn now(&self) -> u64 {
+        critical_section::with(|cs| self.now.borrow(cs).get().as_ticks() as u64)
+    }
+
+    unsafe fn allocate_alarm(&self) -> Option<AlarmHandle> {
+        unimplemented!("MockDriver does not support runtime features that require an executor");
+    }
+
+    fn set_alarm_callback(&self, _alarm: AlarmHandle, _callback: fn(*mut ()), _ctx: *mut ()) {
+        unimplemented!("MockDriver does not support runtime features that require an executor");
+    }
+
+    fn set_alarm(&self, _alarm: AlarmHandle, _timestamp: u64) -> bool {
+        unimplemented!("MockDriver does not support runtime features that require an executor");
+    }
+}

embassy-time/src/lib.rs

@@ -1,5 +1,6 @@
 #![cfg_attr(not(any(feature = "std", feature = "wasm", test)), no_std)]
 #![cfg_attr(feature = "nightly", feature(async_fn_in_trait))]
+#![cfg_attr(feature = "nightly", allow(stable_features, unknown_lints, async_fn_in_trait))]
 #![doc = include_str!("../README.md")]
 #![allow(clippy::new_without_default)]
 #![warn(missing_docs)]
@@ -15,6 +16,12 @@ pub mod queue;
 mod tick;
 mod timer;
 
+#[cfg(feature = "mock-driver")]
+mod driver_mock;
+
+#[cfg(feature = "mock-driver")]
+pub use driver_mock::MockDriver;
+
 #[cfg(feature = "std")]
 mod driver_std;
 #[cfg(feature = "wasm")]

embassy-time/src/tick.rs

@@ -106,6 +106,44 @@ pub const TICK_HZ: u64 = 131_072_000;
 pub const TICK_HZ: u64 = 262_144_000;
 #[cfg(feature = "tick-hz-524_288_000")]
 pub const TICK_HZ: u64 = 524_288_000;
+#[cfg(feature = "tick-hz-20_000")]
+pub const TICK_HZ: u64 = 20_000;
+#[cfg(feature = "tick-hz-40_000")]
+pub const TICK_HZ: u64 = 40_000;
+#[cfg(feature = "tick-hz-80_000")]
+pub const TICK_HZ: u64 = 80_000;
+#[cfg(feature = "tick-hz-160_000")]
+pub const TICK_HZ: u64 = 160_000;
+#[cfg(feature = "tick-hz-320_000")]
+pub const TICK_HZ: u64 = 320_000;
+#[cfg(feature = "tick-hz-640_000")]
+pub const TICK_HZ: u64 = 640_000;
+#[cfg(feature = "tick-hz-1_280_000")]
+pub const TICK_HZ: u64 = 1_280_000;
+#[cfg(feature = "tick-hz-2_560_000")]
+pub const TICK_HZ: u64 = 2_560_000;
+#[cfg(feature = "tick-hz-5_120_000")]
+pub const TICK_HZ: u64 = 5_120_000;
+#[cfg(feature = "tick-hz-10_240_000")]
+pub const TICK_HZ: u64 = 10_240_000;
+#[cfg(feature = "tick-hz-20_480_000")]
+pub const TICK_HZ: u64 = 20_480_000;
+#[cfg(feature = "tick-hz-40_960_000")]
+pub const TICK_HZ: u64 = 40_960_000;
+#[cfg(feature = "tick-hz-81_920_000")]
+pub const TICK_HZ: u64 = 81_920_000;
+#[cfg(feature = "tick-hz-163_840_000")]
+pub const TICK_HZ: u64 = 163_840_000;
+#[cfg(feature = "tick-hz-327_680_000")]
+pub const TICK_HZ: u64 = 327_680_000;
+#[cfg(feature = "tick-hz-655_360_000")]
+pub const TICK_HZ: u64 = 655_360_000;
+#[cfg(feature = "tick-hz-1_310_720_000")]
+pub const TICK_HZ: u64 = 1_310_720_000;
+#[cfg(feature = "tick-hz-2_621_440_000")]
+pub const TICK_HZ: u64 = 2_621_440_000;
+#[cfg(feature = "tick-hz-5_242_880_000")]
+pub const TICK_HZ: u64 = 5_242_880_000;
 #[cfg(feature = "tick-hz-2_000_000")]
 pub const TICK_HZ: u64 = 2_000_000;
 #[cfg(feature = "tick-hz-3_000_000")]
@@ -334,6 +372,25 @@ pub const TICK_HZ: u64 = 980_000_000;
     feature = "tick-hz-131_072_000",
     feature = "tick-hz-262_144_000",
     feature = "tick-hz-524_288_000",
+    feature = "tick-hz-20_000",
+    feature = "tick-hz-40_000",
+    feature = "tick-hz-80_000",
+    feature = "tick-hz-160_000",
+    feature = "tick-hz-320_000",
+    feature = "tick-hz-640_000",
+    feature = "tick-hz-1_280_000",
+    feature = "tick-hz-2_560_000",
+    feature = "tick-hz-5_120_000",
+    feature = "tick-hz-10_240_000",
+    feature = "tick-hz-20_480_000",
+    feature = "tick-hz-40_960_000",
+    feature = "tick-hz-81_920_000",
+    feature = "tick-hz-163_840_000",
+    feature = "tick-hz-327_680_000",
+    feature = "tick-hz-655_360_000",
+    feature = "tick-hz-1_310_720_000",
+    feature = "tick-hz-2_621_440_000",
+    feature = "tick-hz-5_242_880_000",
     feature = "tick-hz-2_000_000",
     feature = "tick-hz-3_000_000",
     feature = "tick-hz-4_000_000",

embassy-usb-driver/src/lib.rs

@@ -1,5 +1,6 @@
 #![no_std]
 #![feature(async_fn_in_trait)]
+#![allow(stable_features, unknown_lints, async_fn_in_trait)]
 #![doc = include_str!("../README.md")]
 #![warn(missing_docs)]
 

embassy-usb-logger/Cargo.toml

@@ -10,9 +10,9 @@ target = "thumbv7em-none-eabi"
 
 [dependencies]
 embassy-usb = { version = "0.1.0", path = "../embassy-usb" }
-embassy-sync = { version = "0.3.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../embassy-sync" }
 embassy-futures = { version = "0.1.0", path = "../embassy-futures" }
 futures = { version = "0.3", default-features = false }
-static_cell = "1"
+static_cell = { version = "2" }
 usbd-hid = "0.6.0"
 log = "0.4"

embassy-usb-logger/src/lib.rs

@@ -19,6 +19,7 @@ pub struct LoggerState<'d> {
     device_descriptor: [u8; 32],
     config_descriptor: [u8; 128],
     bos_descriptor: [u8; 16],
+    msos_descriptor: [u8; 256],
     control_buf: [u8; 64],
 }
 
@@ -30,6 +31,7 @@ impl<'d> LoggerState<'d> {
             device_descriptor: [0; 32],
             config_descriptor: [0; 128],
             bos_descriptor: [0; 16],
+            msos_descriptor: [0; 256],
             control_buf: [0; 64],
         }
     }
@@ -73,6 +75,7 @@ impl<const N: usize> UsbLogger<N> {
             &mut state.device_descriptor,
             &mut state.config_descriptor,
             &mut state.bos_descriptor,
+            &mut state.msos_descriptor,
             &mut state.control_buf,
         );
 

embassy-usb/Cargo.toml

@@ -13,7 +13,6 @@ target = "thumbv7em-none-eabi"
 [features]
 defmt = ["dep:defmt", "embassy-usb-driver/defmt"]
 usbd-hid = ["dep:usbd-hid", "dep:ssmarshal"]
-msos-descriptor = []
 default = ["usbd-hid"]
 
 # BEGIN AUTOGENERATED CONFIG FEATURES
@@ -41,12 +40,12 @@ max-handler-count-8 = []
 [dependencies]
 embassy-futures = { version = "0.1.0", path = "../embassy-futures" }
 embassy-usb-driver = { version = "0.1.0", path = "../embassy-usb-driver" }
-embassy-sync = { version = "0.3.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.4.0", path = "../embassy-sync" }
 embassy-net-driver-channel = { version = "0.2.0", path = "../embassy-net-driver-channel" }
 
 defmt = { version = "0.3", optional = true }
 log = { version = "0.4.14", optional = true }
-heapless = "0.7.10"
+heapless = "0.8"
 
 # for HID
 usbd-hid = { version = "0.6.0", optional = true }

embassy-usb/src/builder.rs

@@ -3,7 +3,6 @@ use heapless::Vec;
 use crate::config::MAX_HANDLER_COUNT;
 use crate::descriptor::{BosWriter, DescriptorWriter};
 use crate::driver::{Driver, Endpoint, EndpointType};
-#[cfg(feature = "msos-descriptor")]
 use crate::msos::{DeviceLevelDescriptor, FunctionLevelDescriptor, MsOsDescriptorWriter};
 use crate::types::{InterfaceNumber, StringIndex};
 use crate::{Handler, Interface, UsbDevice, MAX_INTERFACE_COUNT, STRING_INDEX_CUSTOM_START};
@@ -133,7 +132,6 @@ pub struct Builder<'d, D: Driver<'d>> {
     config_descriptor: DescriptorWriter<'d>,
     bos_descriptor: BosWriter<'d>,
 
-    #[cfg(feature = "msos-descriptor")]
     msos_descriptor: MsOsDescriptorWriter<'d>,
 }
 
@@ -149,7 +147,7 @@ impl<'d, D: Driver<'d>> Builder<'d, D> {
         device_descriptor_buf: &'d mut [u8],
         config_descriptor_buf: &'d mut [u8],
         bos_descriptor_buf: &'d mut [u8],
-        #[cfg(feature = "msos-descriptor")] msos_descriptor_buf: &'d mut [u8],
+        msos_descriptor_buf: &'d mut [u8],
         control_buf: &'d mut [u8],
     ) -> Self {
         // Magic values specified in USB-IF ECN on IADs.
@@ -189,14 +187,12 @@ impl<'d, D: Driver<'d>> Builder<'d, D> {
             config_descriptor,
             bos_descriptor,
 
-            #[cfg(feature = "msos-descriptor")]
             msos_descriptor: MsOsDescriptorWriter::new(msos_descriptor_buf),
         }
     }
 
     /// Creates the [`UsbDevice`] instance with the configuration in this builder.
     pub fn build(mut self) -> UsbDevice<'d, D> {
-        #[cfg(feature = "msos-descriptor")]
         let msos_descriptor = self.msos_descriptor.build(&mut self.bos_descriptor);
 
         self.config_descriptor.end_configuration();
@@ -206,7 +202,6 @@ impl<'d, D: Driver<'d>> Builder<'d, D> {
         info!("USB: device_descriptor used: {}", self.device_descriptor.position());
         info!("USB: config_descriptor used: {}", self.config_descriptor.position());
         info!("USB: bos_descriptor used: {}", self.bos_descriptor.writer.position());
-        #[cfg(feature = "msos-descriptor")]
         info!("USB: msos_descriptor used: {}", msos_descriptor.len());
         info!("USB: control_buf size: {}", self.control_buf.len());
 
@@ -217,10 +212,9 @@ impl<'d, D: Driver<'d>> Builder<'d, D> {
             self.device_descriptor.into_buf(),
             self.config_descriptor.into_buf(),
             self.bos_descriptor.writer.into_buf(),
+            msos_descriptor,
             self.interfaces,
             self.control_buf,
-            #[cfg(feature = "msos-descriptor")]
-            msos_descriptor,
         )
     }
 
@@ -251,7 +245,6 @@ impl<'d, D: Driver<'d>> Builder<'d, D> {
             builder: self,
             iface_count_index,
 
-            #[cfg(feature = "msos-descriptor")]
             first_interface,
         }
     }
@@ -275,7 +268,6 @@ impl<'d, D: Driver<'d>> Builder<'d, D> {
         StringIndex::new(index)
     }
 
-    #[cfg(feature = "msos-descriptor")]
     /// Add an MS OS 2.0 Descriptor Set.
     ///
     /// Panics if called more than once.
@@ -283,13 +275,11 @@ impl<'d, D: Driver<'d>> Builder<'d, D> {
         self.msos_descriptor.header(windows_version, vendor_code);
     }
 
-    #[cfg(feature = "msos-descriptor")]
     /// Add an MS OS 2.0 Device Level Feature Descriptor.
     pub fn msos_feature<T: DeviceLevelDescriptor>(&mut self, desc: T) {
         self.msos_descriptor.device_feature(desc);
     }
 
-    #[cfg(feature = "msos-descriptor")]
     /// Gets the underlying [`MsOsDescriptorWriter`] to allow adding subsets and features for classes that
     /// do not add their own.
     pub fn msos_writer(&mut self) -> &mut MsOsDescriptorWriter<'d> {
@@ -306,13 +296,11 @@ pub struct FunctionBuilder<'a, 'd, D: Driver<'d>> {
     builder: &'a mut Builder<'d, D>,
     iface_count_index: Option<usize>,
 
-    #[cfg(feature = "msos-descriptor")]
     first_interface: InterfaceNumber,
 }
 
 impl<'a, 'd, D: Driver<'d>> Drop for FunctionBuilder<'a, 'd, D> {
     fn drop(&mut self) {
-        #[cfg(feature = "msos-descriptor")]
         self.builder.msos_descriptor.end_function();
     }
 }
@@ -344,7 +332,6 @@ impl<'a, 'd, D: Driver<'d>> FunctionBuilder<'a, 'd, D> {
         }
     }
 
-    #[cfg(feature = "msos-descriptor")]
     /// Add an MS OS 2.0 Function Level Feature Descriptor.
     pub fn msos_feature<T: FunctionLevelDescriptor>(&mut self, desc: T) {
         if !self.builder.msos_descriptor.is_in_config_subset() {
@@ -355,7 +342,6 @@ impl<'a, 'd, D: Driver<'d>> FunctionBuilder<'a, 'd, D> {
             self.builder.msos_descriptor.function(self.first_interface);
         }
 
-        #[cfg(feature = "msos-descriptor")]
         self.builder.msos_descriptor.function_feature(desc);
     }
 }

embassy-usb/src/lib.rs

@@ -175,10 +175,7 @@ pub struct UsbBufferReport {
     /// Number of bos descriptor bytes used
     pub bos_descriptor_used: usize,
     /// Number of msos descriptor bytes used
-    ///
-    /// Will be `None` if the "msos-descriptor" feature is not active.
-    /// Otherwise will return Some(bytes).
-    pub msos_descriptor_used: Option<usize>,
+    pub msos_descriptor_used: usize,
     /// Size of the control buffer
     pub control_buffer_size: usize,
 }
@@ -197,6 +194,7 @@ struct Inner<'d, D: Driver<'d>> {
     device_descriptor: &'d [u8],
     config_descriptor: &'d [u8],
     bos_descriptor: &'d [u8],
+    msos_descriptor: crate::msos::MsOsDescriptorSet<'d>,
 
     device_state: UsbDeviceState,
     suspended: bool,
@@ -212,9 +210,6 @@ struct Inner<'d, D: Driver<'d>> {
 
     interfaces: Vec<Interface, MAX_INTERFACE_COUNT>,
     handlers: Vec<&'d mut dyn Handler, MAX_HANDLER_COUNT>,
-
-    #[cfg(feature = "msos-descriptor")]
-    msos_descriptor: crate::msos::MsOsDescriptorSet<'d>,
 }
 
 impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
@@ -225,9 +220,9 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
         device_descriptor: &'d [u8],
         config_descriptor: &'d [u8],
         bos_descriptor: &'d [u8],
+        msos_descriptor: crate::msos::MsOsDescriptorSet<'d>,
         interfaces: Vec<Interface, MAX_INTERFACE_COUNT>,
         control_buf: &'d mut [u8],
-        #[cfg(feature = "msos-descriptor")] msos_descriptor: crate::msos::MsOsDescriptorSet<'d>,
     ) -> UsbDevice<'d, D> {
         // Start the USB bus.
         // This prevent further allocation by consuming the driver.
@@ -242,6 +237,7 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
                 device_descriptor,
                 config_descriptor,
                 bos_descriptor,
+                msos_descriptor,
 
                 device_state: UsbDeviceState::Unpowered,
                 suspended: false,
@@ -251,8 +247,6 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
                 set_address_pending: false,
                 interfaces,
                 handlers,
-                #[cfg(feature = "msos-descriptor")]
-                msos_descriptor,
             },
         }
     }
@@ -261,16 +255,11 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
     ///
     /// Useful for tuning buffer sizes for actual usage
     pub fn buffer_usage(&self) -> UsbBufferReport {
-        #[cfg(not(feature = "msos-descriptor"))]
-        let mdu = None;
-        #[cfg(feature = "msos-descriptor")]
-        let mdu = Some(self.inner.msos_descriptor.len());
-
         UsbBufferReport {
             device_descriptor_used: self.inner.device_descriptor.len(),
             config_descriptor_used: self.inner.config_descriptor.len(),
             bos_descriptor_used: self.inner.bos_descriptor.len(),
-            msos_descriptor_used: mdu,
+            msos_descriptor_used: self.inner.msos_descriptor.len(),
             control_buffer_size: self.control_buf.len(),
         }
     }
@@ -406,6 +395,16 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
         let max_packet_size = self.control.max_packet_size();
         let mut total = 0;
 
+        if req_length > self.control_buf.len() {
+            warn!(
+                "got CONTROL OUT with length {} higher than the control_buf len {}, rejecting.",
+                req_length,
+                self.control_buf.len()
+            );
+            self.control.reject().await;
+            return;
+        }
+
         let chunks = self.control_buf[..req_length].chunks_mut(max_packet_size);
         for (first, last, chunk) in first_last(chunks) {
             let size = match self.control.data_out(chunk, first, last).await {
@@ -674,7 +673,7 @@ impl<'d, D: Driver<'d>> Inner<'d, D> {
                 }
                 _ => InResponse::Rejected,
             },
-            #[cfg(feature = "msos-descriptor")]
+
             (RequestType::Vendor, Recipient::Device) => {
                 if !self.msos_descriptor.is_empty()
                     && req.request == self.msos_descriptor.vendor_code()

embassy-usb/src/msos.rs

@@ -1,5 +1,3 @@
-#![cfg(feature = "msos-descriptor")]
-
 //! Microsoft OS Descriptors
 //!
 //! <https://docs.microsoft.com/en-us/windows-hardware/drivers/usbcon/microsoft-os-2-0-descriptors-specification>

examples/boot/application/nrf/Cargo.toml

@@ -5,8 +5,8 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.3.0", path = "../../../../embassy-sync" }
-embassy-executor = { version = "0.3.0", path = "../../../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "nightly", "integrated-timers", "arch-cortex-m", "executor-thread"] }
+embassy-sync = { version = "0.4.0", path = "../../../../embassy-sync" }
+embassy-executor = { version = "0.3.3", path = "../../../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "nightly", "integrated-timers", "arch-cortex-m", "executor-thread"] }
 embassy-time = { version = "0.1.5", path = "../../../../embassy-time", features = ["nightly"] }
 embassy-nrf = { version = "0.1.0", path = "../../../../embassy-nrf", features = ["time-driver-rtc1", "gpiote", "nightly"] }
 embassy-boot = { version = "0.1.0", path = "../../../../embassy-boot/boot", features = ["nightly"] }

examples/boot/application/rp/Cargo.toml

@@ -5,8 +5,8 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.3.0", path = "../../../../embassy-sync" }
-embassy-executor = { version = "0.3.0", path = "../../../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "nightly", "integrated-timers", "arch-cortex-m", "executor-thread"] }
+embassy-sync = { version = "0.4.0", path = "../../../../embassy-sync" }
+embassy-executor = { version = "0.3.3", path = "../../../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "nightly", "integrated-timers", "arch-cortex-m", "executor-thread"] }
 embassy-time = { version = "0.1.5", path = "../../../../embassy-time", features = ["nightly"] }
 embassy-rp = { version = "0.1.0", path = "../../../../embassy-rp", features = ["time-driver", "unstable-traits", "nightly"] }
 embassy-boot-rp = { version = "0.1.0", path = "../../../../embassy-boot/rp", features = ["nightly"] }