Extract embassy support into esp-hal-embassy package (#1595)

* Extract embassy support into `esp-hal-embassy` package

* Update relevant packages/examples/tests to get CI green again

* Add back `defmt` support

* Re-export `Executor` and `InterruptExecutor` rather than making `executor` module public

* Document the `esp-hal-embassy` package

* Update `CHANGELOG.md`

* Hack together a "fix" for the `SYSTIMER` time driver

* Make `clippy` shut up

Cargo.toml

@@ -6,6 +6,7 @@ exclude  = [
     "esp-backtrace",
     "esp-build",
     "esp-hal",
+    "esp-hal-embassy",
     "esp-hal-procmacros",
     "esp-hal-smartled",
     "esp-ieee802154",

esp-hal-embassy/Cargo.toml

@@ -0,0 +1,48 @@
+[package]
+name         = "esp-hal-embassy"
+version      = "0.1.0"
+edition      = "2021"
+rust-version = "1.76.0"
+description  = "Embassy support for esp-hal"
+repository   = "https://github.com/esp-rs/esp-hal"
+license      = "MIT OR Apache-2.0"
+
+[package.metadata.docs.rs]
+default-target = "riscv32imac-unknown-none-elf"
+features       = ["esp32c6", "time-timg0"]
+
+[dependencies]
+critical-section    = "1.1.2"
+defmt               = { version = "0.3.8", optional = true }
+document-features   = "0.2.8"
+embassy-executor    = "0.5.0"
+embassy-time-driver = "0.1.0"
+esp-hal             = { version = "0.17.0", path = "../esp-hal" }
+portable-atomic     = "1.6.0"
+
+[build-dependencies]
+cfg-if       = "1.0.0"
+esp-build    = { version = "0.1.0", path = "../esp-build" }
+esp-metadata = { version = "0.1.0", path = "../esp-metadata" }
+
+[features]
+esp32   = ["esp-hal/esp32"]
+esp32c2 = ["esp-hal/esp32c2"]
+esp32c3 = ["esp-hal/esp32c3"]
+esp32c6 = ["esp-hal/esp32c6"]
+esp32h2 = ["esp-hal/esp32h2"]
+esp32s2 = ["esp-hal/esp32s2"]
+esp32s3 = ["esp-hal/esp32s3"]
+
+## Implement `defmt::Format` on certain types.
+defmt = ["dep:defmt", "embassy-executor/defmt", "esp-hal/defmt"]
+## Use the executor-integrated `embassy-time` timer queue.
+integrated-timers = ["embassy-executor/integrated-timers"]
+
+#! ### Time Driver Feature Flags
+## SYSTIMER (16MHz)
+time-systimer-16mhz = ["embassy-time-driver/tick-hz-16_000_000"]
+## SYSTIMER (80MHz)
+time-systimer-80mhz = ["embassy-time-driver/tick-hz-80_000_000"]
+## TIMG0 (1MHz)
+time-timg0 = ["embassy-time-driver/tick-hz-1_000_000"]

esp-hal-embassy/README.md

@@ -0,0 +1,35 @@
+# esp-hal-embassy
+
+[![Crates.io](https://img.shields.io/crates/v/esp-hal-embassy?labelColor=1C2C2E&color=C96329&logo=Rust&style=flat-square)](https://crates.io/crates/esp-hal-embassy)
+[![docs.rs](https://img.shields.io/docsrs/esp-hal-embassy?labelColor=1C2C2E&color=C96329&logo=rust&style=flat-square)](https://docs.rs/esp-hal-embassy)
+![MSRV](https://img.shields.io/badge/MSRV-1.76-blue?labelColor=1C2C2E&style=flat-square)
+![Crates.io](https://img.shields.io/crates/l/esp-hal-embassy?labelColor=1C2C2E&style=flat-square)
+[![Matrix](https://img.shields.io/matrix/esp-rs:matrix.org?label=join%20matrix&labelColor=1C2C2E&color=BEC5C9&logo=matrix&style=flat-square)](https://matrix.to/#/#esp-rs:matrix.org)
+
+[Embassy] support for `esp-hal`.
+
+[embassy]: https://github.com/embassy-rs/embassy
+
+## [Documentation]
+
+[documentation]: https://docs.rs/esp-hal-embassy/
+
+## Minimum Supported Rust Version (MSRV)
+
+This crate is guaranteed to compile on stable Rust 1.76 and up. It _might_
+compile with older versions but that may change in any new patch release.
+
+## License
+
+Licensed under either of:
+
+- Apache License, Version 2.0 ([LICENSE-APACHE](../LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
+- MIT license ([LICENSE-MIT](../LICENSE-MIT) or http://opensource.org/licenses/MIT)
+
+at your option.
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in
+the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without
+any additional terms or conditions.

esp-hal-embassy/build.rs

@@ -0,0 +1,53 @@
+use std::{error::Error, str::FromStr};
+
+use esp_build::assert_unique_used_features;
+use esp_metadata::{Chip, Config};
+
+fn main() -> Result<(), Box<dyn Error>> {
+    // NOTE: update when adding new device support!
+    // Ensure that exactly one chip has been specified:
+    assert_unique_used_features!(
+        "esp32", "esp32c2", "esp32c3", "esp32c6", "esp32h2", "esp32s2", "esp32s3"
+    );
+
+    // If the `embassy` feature is enabled, ensure that a time driver implementation
+    // is available:
+    cfg_if::cfg_if! {
+        if #[cfg(feature = "esp32")] {
+            assert_unique_used_features!("time-timg0");
+        } else if #[cfg(feature = "esp32s2")] {
+            assert_unique_used_features!("time-systimer-80mhz", "time-timg0");
+        } else {
+            assert_unique_used_features!("time-systimer-16mhz", "time-timg0");
+        }
+    }
+
+    // NOTE: update when adding new device support!
+    // Determine the name of the configured device:
+    let device_name = if cfg!(feature = "esp32") {
+        "esp32"
+    } else if cfg!(feature = "esp32c2") {
+        "esp32c2"
+    } else if cfg!(feature = "esp32c3") {
+        "esp32c3"
+    } else if cfg!(feature = "esp32c6") {
+        "esp32c6"
+    } else if cfg!(feature = "esp32h2") {
+        "esp32h2"
+    } else if cfg!(feature = "esp32s2") {
+        "esp32s2"
+    } else if cfg!(feature = "esp32s3") {
+        "esp32s3"
+    } else {
+        unreachable!() // We've confirmed exactly one known device was selected
+    };
+
+    // Load the configuration file for the configured device:
+    let chip = Chip::from_str(device_name)?;
+    let config = Config::for_chip(&chip);
+
+    // Define all necessary configuration symbols for the configured device:
+    config.define_symbols();
+
+    Ok(())
+}

esp-hal/src/embassy/executor/interrupt.rs → esp-hal-embassy/src/executor/interrupt.rs

@@ -1,14 +1,14 @@
 //! Interrupt-mode executor.
+
 use core::{cell::UnsafeCell, mem::MaybeUninit};
 
 use embassy_executor::{raw, SendSpawner};
-use portable_atomic::{AtomicUsize, Ordering};
-
-use crate::{
+use esp_hal::{
     get_core,
     interrupt::{self, InterruptHandler},
     system::SoftwareInterrupt,
 };
+use portable_atomic::{AtomicUsize, Ordering};
 
 static mut EXECUTORS: [CallbackContext; 4] = [
     CallbackContext::new(),
@@ -43,7 +43,7 @@ impl CallbackContext {
     }
 
     fn get(&self) -> *mut raw::Executor {
-        unsafe { (*self.raw_executor.get()) as *mut raw::Executor }
+        unsafe { *self.raw_executor.get() }
     }
 
     fn set(&self, executor: *mut raw::Executor) {
@@ -58,7 +58,7 @@ fn handle_interrupt<const NUM: u8>() {
     swi.reset();
 
     unsafe {
-        let executor = EXECUTORS[NUM as usize].get().as_mut().unwrap();
+        let executor = unwrap!(EXECUTORS[NUM as usize].get().as_mut());
         executor.poll();
     }
 }
@@ -151,7 +151,7 @@ impl<const SWI: u8> InterruptExecutor<SWI> {
         if self.core.load(Ordering::Acquire) == usize::MAX {
             panic!("InterruptExecutor::spawner() called on uninitialized executor.");
         }
-        let executor = unsafe { (&*self.executor.get()).assume_init_ref() };
+        let executor = unsafe { (*self.executor.get()).assume_init_ref() };
         executor.spawner().make_send()
     }
 }

esp-hal/src/embassy/executor/mod.rs → esp-hal-embassy/src/executor/mod.rs

@@ -1,12 +1,11 @@
+pub use self::{interrupt::*, thread::*};
+
 mod interrupt;
 mod thread;
 
-pub use interrupt::*;
-pub use thread::*;
-
 #[export_name = "__pender"]
 fn __pender(context: *mut ()) {
-    use crate::system::SoftwareInterrupt;
+    use esp_hal::system::SoftwareInterrupt;
 
     let context = (context as usize).to_le_bytes();
 

esp-hal/src/embassy/executor/thread.rs → esp-hal-embassy/src/executor/thread.rs

@@ -1,14 +1,14 @@
 //! Multicore-aware thread-mode embassy executor.
+
 use core::marker::PhantomData;
 
 use embassy_executor::{raw, Spawner};
-use portable_atomic::{AtomicBool, Ordering};
+use esp_hal::get_core;
 #[cfg(multi_core)]
-use procmacros::handler;
-
-use crate::get_core;
+use esp_hal::macros::handler;
 #[cfg(multi_core)]
-use crate::peripherals::SYSTEM;
+use esp_hal::peripherals::SYSTEM;
+use portable_atomic::{AtomicBool, Ordering};
 
 pub(crate) const THREAD_MODE_CONTEXT: u8 = 16;
 
@@ -39,7 +39,7 @@ pub(crate) fn pend_thread_mode(core: usize) {
     // If we are pending a task on the current core, we're done. Otherwise, we
     // need to make sure the other core wakes up.
     #[cfg(multi_core)]
-    if core != crate::get_core() as usize {
+    if core != get_core() as usize {
         // We need to clear the interrupt from software. We don't actually
         // need it to trigger and run the interrupt handler, we just need to
         // kick waiti to return.
@@ -78,7 +78,7 @@ impl Executor {
     pub fn new() -> Self {
         #[cfg(multi_core)]
         unsafe {
-            crate::system::SoftwareInterrupt::<3>::steal()
+            esp_hal::system::SoftwareInterrupt::<3>::steal()
                 .set_interrupt_handler(software3_interrupt)
         }
 
@@ -179,3 +179,9 @@ impl Executor {
         // here
     }
 }
+
+impl Default for Executor {
+    fn default() -> Self {
+        Self::new()
+    }
+}