Merge #1423

1423: rp: fix gpio InputFuture and inefficiencies r=pennae a=pennae

InputFuture could not wait for edges without breaking due to a broken From impl, but even if the impl had been correct it would not have worked correctly because raw edge interrupts are sticky and must be cleared from software. also replace critical sections with atomic accesses, and do nvic setup only once.

Co-authored-by: pennae <github@quasiparticle.net>

tests/rp/src/bin/gpio_multicore.rs

@@ -0,0 +1,63 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use defmt::{info, unwrap};
+use embassy_executor::Executor;
+use embassy_executor::_export::StaticCell;
+use embassy_rp::gpio::{Input, Level, Output, Pull};
+use embassy_rp::multicore::{spawn_core1, Stack};
+use embassy_rp::peripherals::{PIN_0, PIN_1};
+use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
+use embassy_sync::channel::Channel;
+use {defmt_rtt as _, panic_probe as _};
+
+static mut CORE1_STACK: Stack<1024> = Stack::new();
+static EXECUTOR0: StaticCell<Executor> = StaticCell::new();
+static EXECUTOR1: StaticCell<Executor> = StaticCell::new();
+static CHANNEL0: Channel<CriticalSectionRawMutex, (), 1> = Channel::new();
+static CHANNEL1: Channel<CriticalSectionRawMutex, (), 1> = Channel::new();
+
+#[cortex_m_rt::entry]
+fn main() -> ! {
+    let p = embassy_rp::init(Default::default());
+    spawn_core1(p.CORE1, unsafe { &mut CORE1_STACK }, move || {
+        let executor1 = EXECUTOR1.init(Executor::new());
+        executor1.run(|spawner| unwrap!(spawner.spawn(core1_task(p.PIN_1))));
+    });
+    let executor0 = EXECUTOR0.init(Executor::new());
+    executor0.run(|spawner| unwrap!(spawner.spawn(core0_task(p.PIN_0))));
+}
+
+#[embassy_executor::task]
+async fn core0_task(p: PIN_0) {
+    info!("CORE0 is running");
+
+    let mut pin = Output::new(p, Level::Low);
+
+    CHANNEL0.send(()).await;
+    CHANNEL1.recv().await;
+
+    pin.set_high();
+
+    CHANNEL1.recv().await;
+
+    info!("Test OK");
+    cortex_m::asm::bkpt();
+}
+
+#[embassy_executor::task]
+async fn core1_task(p: PIN_1) {
+    info!("CORE1 is running");
+
+    CHANNEL0.recv().await;
+
+    let mut pin = Input::new(p, Pull::Down);
+    let wait = pin.wait_for_rising_edge();
+
+    CHANNEL1.send(()).await;
+
+    wait.await;
+
+    CHANNEL1.send(()).await;
+}