Get DMA on H7 working, add usart_dma example for H7.

embassy-stm32/src/dma/bdma.rs

@@ -139,7 +139,7 @@ unsafe fn on_irq() {
 /// safety: must be called only once
 pub(crate) unsafe fn init() {
     pac::interrupts! {
-        (DMA, $irq:ident) => {
+        (BDMA, $irq:ident) => {
             crate::interrupt::$irq::steal().enable();
         };
     }
@@ -209,52 +209,11 @@ pac::bdma_channels! {
     };
 }
 
-// HACK: on stm32h7 "DMA" interrupts are for DMA, not BDMA, so this
-// would cause duplicate interrupt definitions. Do it manually insted
-#[cfg(not(rcc_h7))]
 pac::interrupts! {
-    (DMA, $irq:ident) => {
+    (BDMA, $irq:ident) => {
         #[crate::interrupt]
         unsafe fn $irq () {
             on_irq()
         }
     };
 }
-
-#[cfg(rcc_h7)]
-mod _if_h7 {
-    use super::*;
-
-    #[crate::interrupt]
-    unsafe fn BDMA_CHANNEL0() {
-        on_irq()
-    }
-    #[crate::interrupt]
-    unsafe fn BDMA_CHANNEL1() {
-        on_irq()
-    }
-    #[crate::interrupt]
-    unsafe fn BDMA_CHANNEL2() {
-        on_irq()
-    }
-    #[crate::interrupt]
-    unsafe fn BDMA_CHANNEL3() {
-        on_irq()
-    }
-    #[crate::interrupt]
-    unsafe fn BDMA_CHANNEL4() {
-        on_irq()
-    }
-    #[crate::interrupt]
-    unsafe fn BDMA_CHANNEL5() {
-        on_irq()
-    }
-    #[crate::interrupt]
-    unsafe fn BDMA_CHANNEL6() {
-        on_irq()
-    }
-    #[crate::interrupt]
-    unsafe fn BDMA_CHANNEL7() {
-        on_irq()
-    }
-}

embassy-stm32/src/dma/dma.rs

@@ -3,7 +3,7 @@ use core::task::Poll;
 use atomic_polyfill::{AtomicU8, Ordering};
 use core::future::Future;
 use embassy::interrupt::{Interrupt, InterruptExt};
-use embassy::util::AtomicWaker;
+use embassy::util::{AtomicWaker, OnDrop};
 use futures::future::poll_fn;
 
 use crate::interrupt;
@@ -38,6 +38,7 @@ static STATE: State = State::new();
 
 //async unsafe fn do_transfer(ch: &mut impl Channel, ch_func: u8, src: *const u8, dst: &mut [u8]) {
 
+#[allow(unused)]
 pub(crate) async unsafe fn do_transfer(
     dma: pac::dma::Dma,
     channel_number: u8,
@@ -59,6 +60,15 @@ pub(crate) async unsafe fn do_transfer(
 
     let ch = dma.st(channel_number as _);
 
+    let on_drop = OnDrop::new(|| unsafe {
+        ch.cr().modify(|w| {
+            w.set_tcie(false);
+            w.set_teie(false);
+            w.set_en(false);
+        });
+        while ch.cr().read().en() {}
+    });
+
     #[cfg(dmamux)]
     super::dmamux::configure_dmamux(dmamux_regs, dmamux_ch_num, request);
 
@@ -74,6 +84,7 @@ pub(crate) async unsafe fn do_transfer(
             w.set_pinc(vals::Inc::FIXED);
             w.set_teie(true);
             w.set_tcie(true);
+            w.set_trbuff(true);
             w.set_en(true);
 
             #[cfg(dma_v2)]