Add basic Embassy support

Cargo.toml

@@ -17,6 +17,9 @@ default-target = "x86_64-unknown-linux-gnu"
 [dependencies]
 cortex-m = { version = "0.7.7", features = ["critical-section-single-core"] }
 cortex-m-rt = "0.7.3"
+critical-section = { version = "1.1.3", optional = true }
+embassy-time-driver = { version = "0.1.0", optional = true }
+embassy-sync = { version = "0.6.0", optional = true }
 embedded-dma = "0.2.0"
 embedded-hal = "1.0.0"
 embedded-hal-02 = { package = "embedded-hal", version = "0.2.7", features = [
@@ -31,6 +34,12 @@ void = { version = "1.0.2", default-features = false, optional = true }
 cortex-m = { version = "0.7.7", features = ["critical-section-single-core"] }
 cortex-m-rtic = "1.1.4"
 cortex-m-semihosting = "0.5.0"
+embassy-executor = { version = "0.6", features = [
+  "arch-cortex-m",
+  "executor-thread",
+  "integrated-timers",
+] }
+embassy-time = { version = "0.3.2" }
 panic-halt = "0.2.0"
 panic-itm = "0.4.2"
 panic-semihosting = "0.6.0"
@@ -56,6 +65,15 @@ gd32f190 = ["gd32f1/gd32f190", "device-selected"]
 gd32f190x4 = ["gd32f190"]
 gd32f190x6 = ["gd32f190"]
 gd32f190x8 = ["gd32f190"]
+embassy = [
+  "rt",
+  "dep:critical-section",
+  "dep:embassy-sync",
+  "dep:embassy-time-driver",
+]
+time-driver-tim1 = ["embassy"]
+time-driver-tim2 = ["embassy"]
+time-driver-tim14 = ["embassy"]
 
 [profile.dev]
 incremental = false
@@ -109,3 +127,7 @@ required-features = ["rt"]
 #[[example]]
 #name = "can-rtic"
 #required-features = ["has-can", "rt"]
+
+[[example]]
+name = "embassy"
+required-features = ["time-driver-tim1"]

examples/embassy.rs

@@ -0,0 +1,46 @@
+#![deny(unsafe_code)]
+#![no_std]
+#![no_main]
+
+use panic_halt as _;
+
+use embassy_executor::{self, Spawner};
+use embassy_time::Timer;
+use embedded_hal::digital::OutputPin;
+use gd32f1x0_hal::{embassy, pac, prelude::*, time::MilliSeconds, watchdog::FreeWatchdog};
+
+#[embassy_executor::task]
+async fn blink_task(mut led: impl OutputPin + 'static) {
+    loop {
+        Timer::after_millis(1_000).await;
+        led.set_high().unwrap();
+        Timer::after_millis(1_000).await;
+        led.set_low().unwrap();
+    }
+}
+
+#[embassy_executor::main]
+async fn main(spawner: Spawner) {
+    let p = pac::Peripherals::take().unwrap();
+    let mut rcu = p.rcu.constrain();
+    let mut flash = p.fmc.constrain();
+    let clocks = rcu.cfgr.freeze(&mut flash.ws);
+
+    embassy::init(p.timer1, &clocks, &mut rcu.apb1);
+
+    let mut gpioc = p.gpioc.split(&mut rcu.ahb);
+    let led = gpioc
+        .pc13
+        .into_push_pull_output(&mut gpioc.config)
+        .downgrade();
+
+    // This task will run in parallel with the loop below time-sharing MCU resources
+    spawner.must_spawn(blink_task(led));
+
+    let mut watchdog = FreeWatchdog::new(p.fwdgt);
+    watchdog.start(MilliSeconds(100));
+    loop {
+        Timer::after_micros(500).await;
+        watchdog.feed();
+    }
+}

src/embassy/mod.rs

@@ -0,0 +1,9 @@
+use time_driver::{Bus, EmbassyTimeDriver, Timer};
+
+use crate::rcu::Clocks;
+
+mod time_driver;
+
+pub fn init(timer: Timer, clocks: &Clocks, apb: &mut Bus) {
+    EmbassyTimeDriver::init(timer, clocks, apb)
+}