Merge #1105

1105: embassy-rp: Add multicore support r=Dirbaio a=kalkyl

This PR adds multicore support + critical-section impl using hardware spinlocks.
Based on the rp2040-hal implementation.

Co-authored-by: kalkyl <[email protected]>
Co-authored-by: Henrik Alsér <[email protected]>

2 files changed, 63 insertions, 2 deletions

diff --git a/examples/rp/Cargo.toml b/examples/rp/Cargo.toml
index b07c471af..dfbc26426 100644
--- a/examples/rp/Cargo.toml
+++ b/examples/rp/Cargo.toml
@@ -9,7 +9,7 @@ license = "MIT OR Apache-2.0"
 embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime"] }
-embassy-rp = { version = "0.1.0", path = "../../embassy-rp", features = ["defmt", "unstable-traits", "nightly", "unstable-pac", "time-driver", "pio"] }
+embassy-rp = { version = "0.1.0", path = "../../embassy-rp", features = ["defmt", "unstable-traits", "nightly", "unstable-pac", "time-driver", "pio", "critical-section-impl"] }
 embassy-usb = { version = "0.1.0", path = "../../embassy-usb", features = ["defmt"] }
 embassy-net = { version = "0.1.0", path = "../../embassy-net", features = ["defmt", "nightly", "tcp", "dhcpv4", "medium-ethernet", "pool-16"] }
 embassy-futures = { version = "0.1.0", path = "../../embassy-futures" }
@@ -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"] }
diff --git a/examples/rp/src/bin/multicore.rs b/examples/rp/src/bin/multicore.rs
new file mode 100644
index 000000000..376b2b61e
--- /dev/null
+++ b/examples/rp/src/bin/multicore.rs
@@ -0,0 +1,60 @@
+#![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::multicore::{spawn_core1, Stack};
+use embassy_rp::peripherals::PIN_25;
+use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
+use embassy_sync::channel::Channel;
+use embassy_time::{Duration, Timer};
+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);
+
+    spawn_core1(p.CORE1, unsafe { &mut CORE1_STACK }, 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(),
+        }
+    }
+}