Make SPIv3 work with DMA.

Add both DMA and non-DMA example to H7.

embassy-stm32/src/dma/dma.rs

@@ -88,7 +88,11 @@ pub(crate) unsafe fn do_transfer(
             w.set_dir(dir);
             w.set_msize(vals::Size::BITS8);
             w.set_psize(vals::Size::BITS8);
+            if incr_mem {
                 w.set_minc(vals::Inc::INCREMENTED);
+            } else {
+                w.set_minc(vals::Inc::FIXED);
+            }
             w.set_pinc(vals::Inc::FIXED);
             w.set_teie(true);
             w.set_tcie(true);

embassy-stm32/src/spi/mod.rs

@@ -1,7 +1,7 @@
 #![macro_use]
 
-#[cfg_attr(spi_v1, path = "v1.rs")]
+//#[cfg_attr(spi_v1, path = "v1.rs")]
-#[cfg_attr(spi_v2, path = "v2.rs")]
+//#[cfg_attr(spi_v2, path = "v2.rs")]
 #[cfg_attr(spi_v3, path = "v3.rs")]
 mod _version;
 use crate::{dma, peripherals, rcc::RccPeripheral};

embassy-stm32/src/spi/v3.rs

@@ -18,7 +18,7 @@ use embassy_extras::unborrow;
 use embassy_traits::spi as traits;
 pub use embedded_hal::spi::{Mode, Phase, Polarity, MODE_0, MODE_1, MODE_2, MODE_3};
 
-use futures::future::join;
+use futures::future::join3;
 
 impl WordSize {
     fn dsize(&self) -> u8 {
@@ -110,7 +110,6 @@ impl<'d, T: Instance, Tx, Rx> Spi<'d, T, Tx, Rx> {
                 w.set_crcen(false);
                 w.set_mbr(spi::vals::Mbr(br));
                 w.set_dsize(WordSize::EightBit.dsize());
-                //w.set_fthlv(WordSize::EightBit.frxth());
             });
             T::regs().cr2().modify(|w| {
                 w.set_tsize(0);
@@ -182,16 +181,40 @@ impl<'d, T: Instance, Tx, Rx> Spi<'d, T, Tx, Rx> {
     where
         Tx: TxDmaChannel<T>,
     {
+        Self::set_word_size(WordSize::EightBit);
+        unsafe {
+            T::regs().cr1().modify(|w| {
+                w.set_spe(false);
+            });
+        }
+
         let request = self.txdma.request();
         let dst = T::regs().txdr().ptr() as *mut u8;
         let f = self.txdma.write(request, write, dst);
+
         unsafe {
             T::regs().cfg1().modify(|reg| {
                 reg.set_txdmaen(true);
             });
+            T::regs().cr1().modify(|w| {
+                w.set_spe(true);
+            });
+            T::regs().cr1().modify(|w| {
+                w.set_cstart(true);
+            });
         }
 
         f.await;
+        unsafe {
+            T::regs().cfg1().modify(|reg| {
+                reg.set_rxdmaen(false);
+                reg.set_txdmaen(false);
+            });
+            T::regs().cr1().modify(|w| {
+                w.set_spe(false);
+            });
+        }
+
         Ok(())
     }
 
@@ -201,6 +224,16 @@ impl<'d, T: Instance, Tx, Rx> Spi<'d, T, Tx, Rx> {
         Tx: TxDmaChannel<T>,
         Rx: RxDmaChannel<T>,
     {
+        Self::set_word_size(WordSize::EightBit);
+        unsafe {
+            T::regs().cr1().modify(|w| {
+                w.set_spe(false);
+            });
+            T::regs().cfg1().modify(|reg| {
+                reg.set_rxdmaen(true);
+            });
+        }
+
         let clock_byte_count = read.len();
 
         let rx_request = self.rxdma.request();
@@ -217,11 +250,25 @@ impl<'d, T: Instance, Tx, Rx> Spi<'d, T, Tx, Rx> {
         unsafe {
             T::regs().cfg1().modify(|reg| {
                 reg.set_txdmaen(true);
-                reg.set_rxdmaen(true);
+            });
+            T::regs().cr1().modify(|w| {
+                w.set_spe(true);
+            });
+            T::regs().cr1().modify(|w| {
+                w.set_cstart(true);
             });
         }
 
-        let r = join(tx_f, rx_f).await;
+        join3(tx_f, rx_f, Self::wait_for_idle()).await;
+        unsafe {
+            T::regs().cfg1().modify(|reg| {
+                reg.set_rxdmaen(false);
+                reg.set_txdmaen(false);
+            });
+            T::regs().cr1().modify(|w| {
+                w.set_spe(false);
+            });
+        }
         Ok(())
     }
 
@@ -231,11 +278,21 @@ impl<'d, T: Instance, Tx, Rx> Spi<'d, T, Tx, Rx> {
         Tx: TxDmaChannel<T>,
         Rx: RxDmaChannel<T>,
     {
-        let clock_byte_count = read.len();
+        Self::set_word_size(WordSize::EightBit);
+        unsafe {
+            T::regs().cr1().modify(|w| {
+                w.set_spe(false);
+            });
+            T::regs().cfg1().modify(|reg| {
+                reg.set_rxdmaen(true);
+            });
+        }
 
         let rx_request = self.rxdma.request();
         let rx_src = T::regs().rxdr().ptr() as *mut u8;
-        let rx_f = self.rxdma.read(rx_request, rx_src, read);
+        let rx_f = self
+            .rxdma
+            .read(rx_request, rx_src, &mut read[0..write.len()]);
 
         let tx_request = self.txdma.request();
         let tx_dst = T::regs().txdr().ptr() as *mut u8;
@@ -244,13 +301,38 @@ impl<'d, T: Instance, Tx, Rx> Spi<'d, T, Tx, Rx> {
         unsafe {
             T::regs().cfg1().modify(|reg| {
                 reg.set_txdmaen(true);
-                reg.set_rxdmaen(true);
+            });
+            T::regs().cr1().modify(|w| {
+                w.set_spe(true);
+            });
+            T::regs().cr1().modify(|w| {
+                w.set_cstart(true);
             });
         }
 
-        let r = join(tx_f, rx_f).await;
+        join3(tx_f, rx_f, Self::wait_for_idle()).await;
+        unsafe {
+            T::regs().cfg1().modify(|reg| {
+                reg.set_rxdmaen(false);
+                reg.set_txdmaen(false);
+            });
+            T::regs().cr1().modify(|w| {
+                w.set_spe(false);
+            });
+        }
         Ok(())
     }
+
+    async fn wait_for_idle() {
+        unsafe {
+            while !T::regs().sr().read().txc() {
+                // spin
+            }
+            while T::regs().sr().read().rxplvl().0 > 0 {
+                // spin
+            }
+        }
+    }
 }
 
 impl<'d, T: Instance, Tx, Rx> Drop for Spi<'d, T, Tx, Rx> {

examples/stm32h7/src/bin/spi.rs

@@ -0,0 +1,112 @@
+#![no_std]
+#![no_main]
+#![feature(trait_alias)]
+#![feature(min_type_alias_impl_trait)]
+#![feature(impl_trait_in_bindings)]
+#![feature(type_alias_impl_trait)]
+#![allow(incomplete_features)]
+
+#[path = "../example_common.rs"]
+mod example_common;
+
+use core::fmt::Write;
+use embassy::executor::Executor;
+use embassy::time::Clock;
+use embassy::util::Forever;
+use embassy_stm32::dma::NoDma;
+use example_common::*;
+use embedded_hal::blocking::spi::Transfer;
+
+use hal::prelude::*;
+use stm32h7xx_hal as hal;
+
+use cortex_m_rt::entry;
+use stm32h7::stm32h743 as pac;
+use heapless::String;
+use embassy_stm32::spi::{Spi, Config};
+use embassy_stm32::time::Hertz;
+
+#[embassy::task]
+async fn main_task() {
+    let p = embassy_stm32::init(Default::default());
+
+    let mut spi = Spi::new(
+        p.SPI3,
+        p.PB3,
+        p.PB5,
+        p.PB4,
+        NoDma,
+        NoDma,
+        Hertz(1_000_000),
+        Config::default(),
+    );
+
+    for n in 0u32.. {
+        let mut write: String<128> = String::new();
+        core::write!(&mut write, "Hello DMA World {}!\r\n", n).unwrap();
+        unsafe {
+            let result = spi.transfer(write.as_bytes_mut());
+            if let Err(_) = result {
+                defmt::panic!("crap");
+            }
+        }
+        info!("read via spi: {}", write.as_bytes());
+    }
+}
+
+struct ZeroClock;
+
+impl Clock for ZeroClock {
+    fn now(&self) -> u64 {
+        0
+    }
+}
+
+static EXECUTOR: Forever<Executor> = Forever::new();
+
+#[entry]
+fn main() -> ! {
+    info!("Hello World!");
+
+    let pp = pac::Peripherals::take().unwrap();
+
+    let pwrcfg = pp.PWR.constrain().freeze();
+
+    let rcc = pp.RCC.constrain();
+
+    rcc.sys_ck(96.mhz())
+        .pclk1(48.mhz())
+        .pclk2(48.mhz())
+        .pclk3(48.mhz())
+        .pclk4(48.mhz())
+        .pll1_q_ck(48.mhz())
+        .freeze(pwrcfg, &pp.SYSCFG);
+
+    let pp = unsafe { pac::Peripherals::steal() };
+
+    pp.DBGMCU.cr.modify(|_, w| {
+        w.dbgsleep_d1().set_bit();
+        w.dbgstby_d1().set_bit();
+        w.dbgstop_d1().set_bit();
+        w.d1dbgcken().set_bit();
+        w
+    });
+
+    pp.RCC.ahb4enr.modify(|_, w| {
+        w.gpioaen().set_bit();
+        w.gpioben().set_bit();
+        w.gpiocen().set_bit();
+        w.gpioden().set_bit();
+        w.gpioeen().set_bit();
+        w.gpiofen().set_bit();
+        w
+    });
+
+    unsafe { embassy::time::set_clock(&ZeroClock) };
+
+    let executor = EXECUTOR.put(Executor::new());
+
+    executor.run(|spawner| {
+        unwrap!(spawner.spawn(main_task()));
+    })
+}

examples/stm32h7/src/bin/spi_dma.rs

@@ -0,0 +1,109 @@
+#![no_std]
+#![no_main]
+#![feature(trait_alias)]
+#![feature(min_type_alias_impl_trait)]
+#![feature(impl_trait_in_bindings)]
+#![feature(type_alias_impl_trait)]
+#![allow(incomplete_features)]
+
+#[path = "../example_common.rs"]
+mod example_common;
+use core::fmt::Write;
+use embassy::executor::Executor;
+use embassy::time::Clock;
+use embassy::util::Forever;
+use example_common::*;
+use embassy_traits::spi::FullDuplex;
+
+use hal::prelude::*;
+use stm32h7xx_hal as hal;
+
+use cortex_m_rt::entry;
+use stm32h7::stm32h743 as pac;
+use heapless::String;
+use embassy_stm32::spi::{Spi, Config};
+use embassy_stm32::time::Hertz;
+use core::str::from_utf8;
+
+#[embassy::task]
+async fn main_task() {
+    let p = embassy_stm32::init(Default::default());
+
+    let mut spi = Spi::new(
+        p.SPI3,
+        p.PB3,
+        p.PB5,
+        p.PB4,
+        p.DMA1_CH3,
+        p.DMA1_CH4,
+        Hertz(1_000_000),
+        Config::default(),
+    );
+
+    for n in 0u32.. {
+        let mut write: String<128> = String::new();
+        let mut read = [0;128];
+        core::write!(&mut write, "Hello DMA World {}!\r\n", n).unwrap();
+        // read_write will slice the &mut read down to &write's actual length.
+        spi.read_write(&mut read, write.as_bytes()).await.ok();
+        info!("read via spi+dma: {}", from_utf8(&read).unwrap());
+    }
+
+}
+
+struct ZeroClock;
+
+impl Clock for ZeroClock {
+    fn now(&self) -> u64 {
+        0
+    }
+}
+
+static EXECUTOR: Forever<Executor> = Forever::new();
+
+#[entry]
+fn main() -> ! {
+    info!("Hello World!");
+
+    let pp = pac::Peripherals::take().unwrap();
+
+    let pwrcfg = pp.PWR.constrain().freeze();
+
+    let rcc = pp.RCC.constrain();
+
+    rcc.sys_ck(96.mhz())
+        .pclk1(48.mhz())
+        .pclk2(48.mhz())
+        .pclk3(48.mhz())
+        .pclk4(48.mhz())
+        .pll1_q_ck(48.mhz())
+        .freeze(pwrcfg, &pp.SYSCFG);
+
+    let pp = unsafe { pac::Peripherals::steal() };
+
+    pp.DBGMCU.cr.modify(|_, w| {
+        w.dbgsleep_d1().set_bit();
+        w.dbgstby_d1().set_bit();
+        w.dbgstop_d1().set_bit();
+        w.d1dbgcken().set_bit();
+        w
+    });
+
+    pp.RCC.ahb4enr.modify(|_, w| {
+        w.gpioaen().set_bit();
+        w.gpioben().set_bit();
+        w.gpiocen().set_bit();
+        w.gpioden().set_bit();
+        w.gpioeen().set_bit();
+        w.gpiofen().set_bit();
+        w
+    });
+
+    unsafe { embassy::time::set_clock(&ZeroClock) };
+
+    let executor = EXECUTOR.put(Executor::new());
+
+    executor.run(|spawner| {
+        unwrap!(spawner.spawn(main_task()));
+    })
+}