Merge #913

913: (embassy-rp): Add DMA implementation r=Dirbaio a=MathiasKoch

This PR adds everything necessary to do peripheral to memory DMA & memory to memory DMA operations.

It also adds async UART read & write, powered by DMA

Co-authored-by: Mathias <[email protected]>

3 files changed, 105 insertions, 0 deletions

diff --git a/tests/rp/src/bin/dma_copy_async.rs b/tests/rp/src/bin/dma_copy_async.rs
new file mode 100644
index 000000000..c53f644bd
--- /dev/null
+++ b/tests/rp/src/bin/dma_copy_async.rs
@@ -0,0 +1,41 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use defmt::{assert_eq, *};
+use embassy_executor::Spawner;
+use embassy_rp::dma::copy;
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let p = embassy_rp::init(Default::default());
+    info!("Hello World!");
+
+    // Check `u8` copy
+    {
+        let data: [u8; 2] = [0xC0, 0xDE];
+        let mut buf = [0; 2];
+        unsafe { copy(p.DMA_CH0, &data, &mut buf).await };
+        assert_eq!(buf, data);
+    }
+
+    // Check `u16` copy
+    {
+        let data: [u16; 2] = [0xC0BE, 0xDEAD];
+        let mut buf = [0; 2];
+        unsafe { copy(p.DMA_CH1, &data, &mut buf).await };
+        assert_eq!(buf, data);
+    }
+
+    // Check `u32` copy
+    {
+        let data: [u32; 2] = [0xC0BEDEAD, 0xDEADAAFF];
+        let mut buf = [0; 2];
+        unsafe { copy(p.DMA_CH2, &data, &mut buf).await };
+        assert_eq!(buf, data);
+    }
+
+    info!("Test OK");
+    cortex_m::asm::bkpt();
+}
diff --git a/tests/rp/src/bin/uart.rs b/tests/rp/src/bin/uart.rs
new file mode 100644
index 000000000..92f61464e
--- /dev/null
+++ b/tests/rp/src/bin/uart.rs
@@ -0,0 +1,32 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use defmt::{assert_eq, *};
+use embassy_executor::Spawner;
+use embassy_rp::uart::{Config, Uart};
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let p = embassy_rp::init(Default::default());
+    info!("Hello World!");
+
+    let (tx, rx, uart) = (p.PIN_0, p.PIN_1, p.UART0);
+
+    let config = Config::default();
+    let mut uart = Uart::new_blocking(uart, tx, rx, config);
+
+    // We can't send too many bytes, they have to fit in the FIFO.
+    // This is because we aren't sending+receiving at the same time.
+
+    let data = [0xC0, 0xDE];
+    uart.blocking_write(&data).unwrap();
+
+    let mut buf = [0; 2];
+    uart.blocking_read(&mut buf).unwrap();
+    assert_eq!(buf, data);
+
+    info!("Test OK");
+    cortex_m::asm::bkpt();
+}
diff --git a/tests/rp/src/bin/uart_dma.rs b/tests/rp/src/bin/uart_dma.rs
new file mode 100644
index 000000000..963c22707
--- /dev/null
+++ b/tests/rp/src/bin/uart_dma.rs
@@ -0,0 +1,32 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use defmt::{assert_eq, *};
+use embassy_executor::Spawner;
+use embassy_rp::uart::{Config, Uart};
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let p = embassy_rp::init(Default::default());
+    info!("Hello World!");
+
+    let (tx, rx, uart) = (p.PIN_0, p.PIN_1, p.UART0);
+
+    let config = Config::default();
+    let mut uart = Uart::new(uart, tx, rx, p.DMA_CH0, p.DMA_CH1, config);
+
+    // We can't send too many bytes, they have to fit in the FIFO.
+    // This is because we aren't sending+receiving at the same time.
+
+    let data = [0xC0, 0xDE];
+    uart.write(&data).await.unwrap();
+
+    let mut buf = [0; 2];
+    uart.read(&mut buf).await.unwrap();
+    assert_eq!(buf, data);
+
+    info!("Test OK");
+    cortex_m::asm::bkpt();
+}