embassy-rp: Add multicore support

examples/rp/Cargo.toml

@@ -18,7 +18,8 @@ embassy-usb-logger = { version = "0.1.0", path = "../../embassy-usb-logger" }
 defmt = "0.3"
 defmt-rtt = "0.4"
 
-cortex-m = { version = "0.7.6", features = ["critical-section-single-core"] }
+#cortex-m = { version = "0.7.6", features = ["critical-section-single-core"] }
+cortex-m = { version = "0.7.6" }
 cortex-m-rt = "0.7.0"
 panic-probe = { version = "0.3", features = ["print-defmt"] }
 futures = { version = "0.3.17", default-features = false, features = ["async-await", "cfg-target-has-atomic", "unstable"] }

examples/rp/src/bin/multicore.rs

@@ -0,0 +1,62 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use defmt::*;
+use embassy_executor::Executor;
+use embassy_executor::_export::StaticCell;
+use embassy_rp::gpio::{Level, Output};
+use embassy_rp::peripherals::PIN_25;
+use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
+use embassy_sync::channel::Channel;
+use embassy_time::{Duration, Timer};
+use embassy_rp::multicore::{Multicore, Stack};
+use {defmt_rtt as _, panic_probe as _};
+
+static mut CORE1_STACK: Stack<4096> = Stack::new();
+static EXECUTOR0: StaticCell<Executor> = StaticCell::new();
+static EXECUTOR1: StaticCell<Executor> = StaticCell::new();
+static CHANNEL: Channel<CriticalSectionRawMutex, LedState, 1> = Channel::new();
+
+enum LedState {
+    On,
+    Off,
+}
+
+#[cortex_m_rt::entry]
+fn main() -> ! {
+    let p = embassy_rp::init(Default::default());
+    let led = Output::new(p.PIN_25, Level::Low);
+
+    let mut mc = Multicore::new();
+    let (_, core1) = mc.cores();
+    let _ = core1.spawn(unsafe { &mut CORE1_STACK.mem }, move || {
+        let executor1 = EXECUTOR1.init(Executor::new());
+        executor1.run(|spawner| unwrap!(spawner.spawn(core1_task(led))));
+    });
+
+    let executor0 = EXECUTOR0.init(Executor::new());
+    executor0.run(|spawner| unwrap!(spawner.spawn(core0_task())));
+}
+
+#[embassy_executor::task]
+async fn core0_task() {
+    info!("Hello from core 0");
+    loop {
+        CHANNEL.send(LedState::On).await;
+        Timer::after(Duration::from_millis(100)).await;
+        CHANNEL.send(LedState::Off).await;
+        Timer::after(Duration::from_millis(400)).await;
+    }
+}
+
+#[embassy_executor::task]
+async fn core1_task(mut led: Output<'static, PIN_25>) {
+    info!("Hello from core 1");
+    loop {
+        match CHANNEL.recv().await {
+            LedState::On => led.set_high(),
+            LedState::Off => led.set_low(),
+        }
+    }
+}