stm32: add stm32u5 GPDMA, SPIv4 support, add HIL tests.

2 files changed, 318 insertions, 4 deletions

diff --git a/embassy-stm32/src/dma/gpdma.rs b/embassy-stm32/src/dma/gpdma.rs
new file mode 100644
index 000000000..0cb986b32
--- /dev/null
+++ b/embassy-stm32/src/dma/gpdma.rs
@@ -0,0 +1,293 @@
+use core::sync::atomic::{fence, Ordering};
+use core::task::Waker;
+
+use embassy::interrupt::{Interrupt, InterruptExt};
+use embassy::waitqueue::AtomicWaker;
+
+use crate::_generated::GPDMA_CHANNEL_COUNT;
+use crate::interrupt;
+use crate::pac;
+use crate::pac::gpdma::{vals, Gpdma};
+
+use super::{Request, TransferOptions, Word, WordSize};
+
+impl From<WordSize> for vals::ChTr1Dw {
+    fn from(raw: WordSize) -> Self {
+        match raw {
+            WordSize::OneByte => Self::BYTE,
+            WordSize::TwoBytes => Self::HALFWORD,
+            WordSize::FourBytes => Self::WORD,
+        }
+    }
+}
+
+struct ChannelState {
+    waker: AtomicWaker,
+}
+
+impl ChannelState {
+    const fn new() -> Self {
+        Self {
+            waker: AtomicWaker::new(),
+        }
+    }
+}
+
+struct State {
+    channels: [ChannelState; GPDMA_CHANNEL_COUNT],
+}
+
+impl State {
+    const fn new() -> Self {
+        const CH: ChannelState = ChannelState::new();
+        Self {
+            channels: [CH; GPDMA_CHANNEL_COUNT],
+        }
+    }
+}
+
+static STATE: State = State::new();
+
+/// safety: must be called only once
+pub(crate) unsafe fn init() {
+    foreach_interrupt! {
+        ($peri:ident, gpdma, $block:ident, $signal_name:ident, $irq:ident) => {
+            interrupt::$irq::steal().enable();
+        };
+    }
+    crate::_generated::init_gpdma();
+}
+
+foreach_dma_channel! {
+    ($channel_peri:ident, $dma_peri:ident, gpdma, $channel_num:expr, $index:expr, $dmamux:tt) => {
+        impl crate::dma::sealed::Channel for crate::peripherals::$channel_peri {
+            unsafe fn start_write<W: Word>(&mut self, request: Request, buf: *const [W], reg_addr: *mut W, options: TransferOptions) {
+                let (ptr, len) = super::slice_ptr_parts(buf);
+                low_level_api::start_transfer(
+                    pac::$dma_peri,
+                    $channel_num,
+                    request,
+                    low_level_api::Dir::MemoryToPeripheral,
+                    reg_addr as *const u32,
+                    ptr as *mut u32,
+                    len,
+                    true,
+                    W::bits(),
+                    options,
+                )
+            }
+
+            unsafe fn start_write_repeated<W: Word>(&mut self, request: Request, repeated: W, count: usize, reg_addr: *mut W, options: TransferOptions) {
+                let buf = [repeated];
+                low_level_api::start_transfer(
+                    pac::$dma_peri,
+                    $channel_num,
+                    request,
+                    low_level_api::Dir::MemoryToPeripheral,
+                    reg_addr as *const u32,
+                    buf.as_ptr() as *mut u32,
+                    count,
+                    false,
+                    W::bits(),
+                    options,
+                )
+            }
+
+            unsafe fn start_read<W: Word>(&mut self, request: Request, reg_addr: *const W, buf: *mut [W], options: TransferOptions) {
+                let (ptr, len) = super::slice_ptr_parts_mut(buf);
+                low_level_api::start_transfer(
+                    pac::$dma_peri,
+                    $channel_num,
+                    request,
+                    low_level_api::Dir::PeripheralToMemory,
+                    reg_addr as *const u32,
+                    ptr as *mut u32,
+                    len,
+                    true,
+                    W::bits(),
+                    options,
+                );
+            }
+
+            unsafe fn start_double_buffered_read<W: Word>(
+                &mut self,
+                _request: Request,
+                _reg_addr: *const W,
+                _buffer0: *mut W,
+                _buffer1: *mut W,
+                _buffer_len: usize,
+                _options: TransferOptions,
+            ) {
+                panic!("Unsafe double buffered mode is unavailable on GPBDMA");
+            }
+
+            unsafe fn set_buffer0<W: Word>(&mut self, _buffer: *mut W) {
+                panic!("Unsafe double buffered mode is unavailable on GPBDMA");
+            }
+
+            unsafe fn set_buffer1<W: Word>(&mut self, _buffer: *mut W) {
+                panic!("Unsafe double buffered mode is unavailable on GPBDMA");
+            }
+
+            unsafe fn is_buffer0_accessible(&mut self) -> bool {
+                panic!("Unsafe double buffered mode is unavailable on GPBDMA");
+            }
+
+            fn request_stop(&mut self) {
+                unsafe {low_level_api::request_stop(pac::$dma_peri, $channel_num);}
+            }
+
+            fn is_running(&self) -> bool {
+                unsafe {low_level_api::is_running(pac::$dma_peri, $channel_num)}
+            }
+
+            fn remaining_transfers(&mut self) -> u16 {
+                unsafe {low_level_api::get_remaining_transfers(pac::$dma_peri, $channel_num)}
+            }
+
+            fn set_waker(&mut self, waker: &Waker) {
+                unsafe {low_level_api::set_waker($index, waker )}
+            }
+
+            fn on_irq() {
+                unsafe {
+                    low_level_api::on_irq_inner(pac::$dma_peri, $channel_num, $index);
+                }
+            }
+        }
+        impl crate::dma::Channel for crate::peripherals::$channel_peri { }
+    };
+}
+
+mod low_level_api {
+    use super::*;
+
+    #[derive(Debug, Copy, Clone, PartialEq, Eq)]
+    #[cfg_attr(feature = "defmt", derive(defmt::Format))]
+    pub enum Dir {
+        MemoryToPeripheral,
+        PeripheralToMemory,
+    }
+
+    pub unsafe fn start_transfer(
+        dma: Gpdma,
+        channel_number: u8,
+        request: Request,
+        dir: Dir,
+        peri_addr: *const u32,
+        mem_addr: *mut u32,
+        mem_len: usize,
+        incr_mem: bool,
+        data_size: WordSize,
+        _options: TransferOptions,
+    ) {
+        // "Preceding reads and writes cannot be moved past subsequent writes."
+        fence(Ordering::SeqCst);
+
+        let ch = dma.ch(channel_number as _);
+        ch.llr().write(|_| {}); // no linked list
+        ch.tr1().write(|w| {
+            w.set_sdw(data_size.into());
+            w.set_ddw(data_size.into());
+            w.set_sinc(dir == Dir::MemoryToPeripheral && incr_mem);
+            w.set_dinc(dir == Dir::PeripheralToMemory && incr_mem);
+        });
+        ch.tr2().write(|w| {
+            w.set_dreq(match dir {
+                Dir::MemoryToPeripheral => vals::ChTr2Dreq::DESTINATIONPERIPHERAL,
+                Dir::PeripheralToMemory => vals::ChTr2Dreq::SOURCEPERIPHERAL,
+            });
+            w.set_reqsel(request);
+        });
+        ch.br1().write(|w| {
+            // BNDT is specified as bytes, not as number of transfers.
+            w.set_bndt((mem_len * data_size.bytes()) as u16)
+        });
+
+        match dir {
+            Dir::MemoryToPeripheral => {
+                ch.sar().write_value(mem_addr as _);
+                ch.dar().write_value(peri_addr as _);
+            }
+            Dir::PeripheralToMemory => {
+                ch.sar().write_value(peri_addr as _);
+                ch.dar().write_value(mem_addr as _);
+            }
+        }
+
+        ch.cr().write(|w| {
+            // Enable interrupts
+            w.set_tcie(true);
+            w.set_useie(true);
+            w.set_dteie(true);
+            w.set_suspie(true);
+
+            // Start it
+            w.set_en(true);
+        });
+    }
+
+    /// Stops the DMA channel.
+    pub unsafe fn request_stop(dma: Gpdma, channel_number: u8) {
+        // get a handle on the channel itself
+        let ch = dma.ch(channel_number as _);
+
+        // Disable the channel. Keep the IEs enabled so the irqs still fire.
+        ch.cr().write(|w| {
+            w.set_tcie(true);
+            w.set_useie(true);
+            w.set_dteie(true);
+            w.set_suspie(true);
+        });
+
+        // "Subsequent reads and writes cannot be moved ahead of preceding reads."
+        fence(Ordering::SeqCst);
+    }
+
+    /// Gets the running status of the channel
+    pub unsafe fn is_running(dma: Gpdma, ch: u8) -> bool {
+        let ch = dma.ch(ch as _);
+        !ch.sr().read().idlef()
+    }
+
+    /// Gets the total remaining transfers for the channel
+    /// Note: this will be zero for transfers that completed without cancellation.
+    pub unsafe fn get_remaining_transfers(dma: Gpdma, ch: u8) -> u16 {
+        // get a handle on the channel itself
+        let ch = dma.ch(ch as _);
+        // read the remaining transfer count. If this is zero, the transfer completed fully.
+        ch.br1().read().bndt()
+    }
+
+    /// Sets the waker for the specified DMA channel
+    pub unsafe fn set_waker(state_number: usize, waker: &Waker) {
+        STATE.channels[state_number].waker.register(waker);
+    }
+
+    /// Safety: Must be called with a matching set of parameters for a valid dma channel
+    pub unsafe fn on_irq_inner(dma: Gpdma, channel_num: u8, state_index: u8) {
+        let channel_num = channel_num as usize;
+        let state_index = state_index as usize;
+
+        let ch = dma.ch(channel_num);
+        let sr = ch.sr().read();
+
+        if sr.dtef() {
+            panic!(
+                "DMA: data transfer error on DMA@{:08x} channel {}",
+                dma.0 as u32, channel_num
+            );
+        }
+        if sr.usef() {
+            panic!(
+                "DMA: user settings error on DMA@{:08x} channel {}",
+                dma.0 as u32, channel_num
+            );
+        }
+
+        if sr.suspf() || sr.tcf() {
+            ch.cr().write(|w| w.set_reset(true));
+            STATE.channels[state_index].waker.wake();
+        }
+    }
+}
diff --git a/embassy-stm32/src/dma/mod.rs b/embassy-stm32/src/dma/mod.rs
index f96ccbf6e..c19f7b3c7 100644
--- a/embassy-stm32/src/dma/mod.rs
+++ b/embassy-stm32/src/dma/mod.rs
@@ -4,6 +4,8 @@ pub(crate) mod bdma;
 pub(crate) mod dma;
 #[cfg(dmamux)]
 mod dmamux;
+#[cfg(gpdma)]
+mod gpdma;
 
 #[cfg(dmamux)]
 pub use dmamux::*;
@@ -24,9 +26,9 @@ pub mod low_level {
 
 pub(crate) use transfers::*;
 
-#[cfg(any(bdma_v2, dma_v2, dmamux))]
+#[cfg(any(bdma_v2, dma_v2, dmamux, gpdma))]
 pub type Request = u8;
-#[cfg(not(any(bdma_v2, dma_v2, dmamux)))]
+#[cfg(not(any(bdma_v2, dma_v2, dmamux, gpdma)))]
 pub type Request = ();
 
 pub(crate) mod sealed {
@@ -118,11 +120,24 @@ pub(crate) mod sealed {
     }
 }
 
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum WordSize {
     OneByte,
     TwoBytes,
     FourBytes,
 }
+
+impl WordSize {
+    pub fn bytes(&self) -> usize {
+        match self {
+            Self::OneByte => 1,
+            Self::TwoBytes => 2,
+            Self::FourBytes => 4,
+        }
+    }
+}
+
 pub trait Word: sealed::Word {
     fn bits() -> WordSize;
 }
@@ -148,7 +163,8 @@ impl Word for u32 {
     }
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum Burst {
     /// Single transfer
     Single,
@@ -160,7 +176,8 @@ pub enum Burst {
     Incr16,
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub enum FlowControl {
     /// Flow control by DMA
     Dma,
@@ -168,6 +185,8 @@ pub enum FlowControl {
     Peripheral,
 }
 
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct TransferOptions {
     /// Peripheral burst transfer configuration
     pub pburst: Burst,
@@ -299,6 +318,8 @@ pub(crate) unsafe fn init() {
     dma::init();
     #[cfg(dmamux)]
     dmamux::init();
+    #[cfg(gpdma)]
+    gpdma::init();
 }
 
 // TODO: replace transmutes with core::ptr::metadata once it's stable