Async F4 flash driver

embassy-stm32/src/flash/f4.rs

@@ -1,11 +1,14 @@
 use core::convert::TryInto;
 use core::ptr::write_volatile;
+use core::task::Poll;
 
 use atomic_polyfill::{fence, Ordering};
+use embassy::waitqueue::AtomicWaker;
+use futures::future::poll_fn;
 
 use super::{ERASE_SIZE, FLASH_BASE, FLASH_SIZE};
 use crate::flash::Error;
-use crate::pac;
+use crate::{interrupt, pac};
 
 const SECOND_BANK_SECTOR_START: u32 = 12;
 
@@ -110,14 +113,14 @@ pub(crate) unsafe fn blocking_erase(from: u32, to: u32) -> Result<(), Error> {
 
     while addr < to {
         let sector = get_sector(addr, dual_bank);
-        erase_sector(sector.index)?;
+        blocking_erase_sector(sector.index)?;
         addr += sector.size;
     }
 
     Ok(())
 }
 
-unsafe fn erase_sector(sector: u8) -> Result<(), Error> {
+unsafe fn blocking_erase_sector(sector: u8) -> Result<(), Error> {
     let bank = sector / SECOND_BANK_SECTOR_START as u8;
     let snb = (bank << 4) + (sector % SECOND_BANK_SECTOR_START as u8);
 
@@ -145,7 +148,6 @@ pub(crate) unsafe fn clear_all_err() {
         w.set_pgperr(true);
         w.set_pgaerr(true);
         w.set_wrperr(true);
-        w.set_eop(true);
     });
 }
 
@@ -174,3 +176,126 @@ pub(crate) unsafe fn blocking_wait_ready() -> Result<(), Error> {
         }
     }
 }
+
+pub(crate) async unsafe fn write(offset: u32, buf: &[u8]) -> Result<(), Error> {
+    pac::FLASH.cr().write(|w| {
+        w.set_pg(true);
+        w.set_psize(pac::flash::vals::Psize::PSIZE32);
+        w.set_eopie(true);
+        w.set_errie(true);
+    });
+
+    let ret = {
+        let mut ret: Result<(), Error> = Ok(());
+        let mut offset = offset;
+        for chunk in buf.chunks(super::WRITE_SIZE) {
+            for val in chunk.chunks(4) {
+                write_volatile(offset as *mut u32, u32::from_le_bytes(val[0..4].try_into().unwrap()));
+                offset += val.len() as u32;
+
+                // prevents parallelism errors
+                fence(Ordering::SeqCst);
+            }
+
+            ret = wait_ready().await;
+
+            if ret.is_err() {
+                break;
+            }
+        }
+        ret
+    };
+
+    pac::FLASH.cr().write(|w| {
+        w.set_pg(false);
+        w.set_eopie(false);
+        w.set_errie(false);
+});
+
+    ret
+}
+
+pub(crate) async unsafe fn erase(from: u32, to: u32) -> Result<(), Error> {
+    let mut addr = from;
+    let dual_bank = is_dual_bank();
+
+    while addr < to {
+        let sector = get_sector(addr, dual_bank);
+        erase_sector(sector.index).await?;
+        addr += sector.size;
+    }
+
+    Ok(())
+}
+
+async unsafe fn erase_sector(sector: u8) -> Result<(), Error> {
+    let bank = sector / SECOND_BANK_SECTOR_START as u8;
+    let snb = (bank << 4) + (sector % SECOND_BANK_SECTOR_START as u8);
+
+    trace!("Erasing sector: {}", sector);
+
+    pac::FLASH.cr().modify(|w| {
+        w.set_ser(true);
+        w.set_snb(snb);
+        w.set_eopie(true);
+        w.set_errie(true);
+    });
+
+    pac::FLASH.cr().modify(|w| {
+        w.set_strt(true);
+    });
+
+    let ret: Result<(), Error> = wait_ready().await;
+
+    pac::FLASH.cr().modify(|w| {
+        w.set_eopie(false);
+        w.set_errie(false);
+    });
+
+    clear_all_err();
+
+    ret
+}
+
+static WAKER: AtomicWaker = AtomicWaker::new();
+
+pub(crate) async unsafe fn wait_ready() -> Result<(), Error> {
+    poll_fn(|cx| {
+        WAKER.register(cx.waker());
+
+        let sr = pac::FLASH.sr().read();
+
+        if !sr.bsy() {
+            Poll::Ready(if sr.pgserr() {
+                Err(Error::Seq)
+            } else if sr.pgperr() {
+                Err(Error::Parallelism)
+            } else if sr.pgaerr() {
+                Err(Error::Unaligned)
+            } else if sr.wrperr() {
+                Err(Error::Protected)
+            } else {
+                Ok(())
+            })
+        } else {
+            return Poll::Pending;
+        }
+    })
+    .await
+}
+
+pub(crate) unsafe fn init() {
+    use embassy_cortex_m::interrupt::{Interrupt, InterruptExt};
+    crate::interrupt::FLASH::steal().enable();
+}
+
+#[interrupt]
+unsafe fn FLASH() {
+    // Clear IRQ flags
+    pac::FLASH.sr().write(|w| {
+        w.set_operr(true);
+        w.set_eop(true);
+    });
+
+    WAKER.wake();
+}

embassy-stm32/src/flash/mod.rs

@@ -23,6 +23,9 @@ pub struct Flash<'d> {
 impl<'d> Flash<'d> {
     pub fn new(p: impl Unborrow<Target = FLASH>) -> Self {
         unborrow!(p);
+
+        unsafe { family::init(); }
+
         Self {
             _inner: p,
             _phantom: PhantomData,
@@ -143,45 +146,67 @@ impl<'d> NorFlash for Flash<'d> {
     }
 }
 
-/*
-cfg_if::cfg_if! {
-    if #[cfg(feature = "nightly")]
-    {
-        use embedded_storage_async::nor_flash::{AsyncNorFlash, AsyncReadNorFlash};
+#[cfg(all(feature = "nightly", flash_f4))]
+mod asynch {
     use core::future::Future;
 
-        impl<'d> AsyncNorFlash for Flash<'d> {
-            const WRITE_SIZE: usize = <Self as NorFlash>::WRITE_SIZE;
-            const ERASE_SIZE: usize = <Self as NorFlash>::ERASE_SIZE;
+    use embedded_storage::nor_flash::{NorFlash, ReadNorFlash};
+    use embedded_storage_async::nor_flash::{AsyncNorFlash, AsyncReadNorFlash};
 
-            type WriteFuture<'a> = impl Future<Output = Result<(), Self::Error>> + 'a where Self: 'a;
-            fn write<'a>(&'a mut self, offset: u32, data: &'a [u8]) -> Self::WriteFuture<'a> {
-                async move {
-                    todo!()
-                }
-            }
-
-            type EraseFuture<'a> = impl Future<Output = Result<(), Self::Error>> + 'a where Self: 'a;
-            fn erase<'a>(&'a mut self, from: u32, to: u32) -> Self::EraseFuture<'a> {
-                async move {
-                    todo!()
-                }
-            }
-        }
+    use super::{family, Error, Flash, ERASE_SIZE, FLASH_BASE, FLASH_END, FLASH_SIZE, WRITE_SIZE};
 
     impl<'d> AsyncReadNorFlash for Flash<'d> {
         const READ_SIZE: usize = <Self as ReadNorFlash>::READ_SIZE;
         type ReadFuture<'a> = impl Future<Output = Result<(), Self::Error>> + 'a where Self: 'a;
-            fn read<'a>(&'a mut self, address: u32, data: &'a mut [u8]) -> Self::ReadFuture<'a> {
-                async move {
-                    todo!()
-                }
+
+        fn read<'a>(&'a mut self, offset: u32, bytes: &'a mut [u8]) -> Self::ReadFuture<'a> {
+            async move { self.blocking_read(offset, bytes) }
         }
 
         fn capacity(&self) -> usize {
             FLASH_SIZE
         }
     }
+
+    impl<'d> AsyncNorFlash for Flash<'d> {
+        const WRITE_SIZE: usize = <Self as NorFlash>::WRITE_SIZE;
+        const ERASE_SIZE: usize = <Self as NorFlash>::ERASE_SIZE;
+
+        type WriteFuture<'a> = impl Future<Output = Result<(), Self::Error>> + 'a where Self: 'a;
+
+        fn write<'a>(&'a mut self, offset: u32, data: &'a [u8]) -> Self::WriteFuture<'a> {
+            async move {
+                let addr = FLASH_BASE as u32 + offset;
+                if addr as usize + data.len() > FLASH_END {
+                    return Err(Error::Size);
+                }
+                if addr as usize % WRITE_SIZE != 0 || data.len() as usize % WRITE_SIZE != 0 {
+                    return Err(Error::Unaligned);
+                }
+                trace!("Writing {} bytes at 0x{:x}", data.len(), addr);
+        
+                self.clear_all_err();
+        
+                unsafe { family::write(addr, data).await }
+            }
+        }
+
+        type EraseFuture<'a> = impl Future<Output = Result<(), Self::Error>> + 'a where Self: 'a;
+
+        fn erase<'a>(&'a mut self, from: u32, to: u32) -> Self::EraseFuture<'a> {
+            async move {
+                let from = FLASH_BASE as u32 + from;
+                let to = FLASH_BASE as u32 + to;
+                if to < from || to as usize > FLASH_END {
+                    return Err(Error::Size);
+                }
+                if (from as usize % ERASE_SIZE) != 0 || (to as usize % ERASE_SIZE) != 0 {
+                    return Err(Error::Unaligned);
+                }
+
+                self.clear_all_err();
+                unsafe { family::erase(from, to).await }
+            }
+        }
     }
 }
-*/

examples/stm32f4/Cargo.toml

@@ -20,6 +20,7 @@ futures = { version = "0.3.17", default-features = false, features = ["async-awa
 heapless = { version = "0.7.5", default-features = false }
 nb = "1.0.0"
 embedded-storage = "0.3.0"
+embedded-storage-async = "0.3.0"
 
 usb-device = "0.2"
 usbd-serial = "0.1.1"

examples/stm32f4/src/bin/flash_async.rs

@@ -0,0 +1,83 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use defmt::{info, unwrap};
+use embassy::executor::Spawner;
+use embassy::time::{Duration, Timer};
+use embassy_stm32::flash::Flash;
+use embassy_stm32::Peripherals;
+use embassy_stm32::gpio::{AnyPin, Level, Speed, Output, Pin};
+use embedded_storage_async::nor_flash::{AsyncReadNorFlash, AsyncNorFlash};
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy::task]
+async fn blinky(p: AnyPin) {
+    let mut led = Output::new(p, Level::High, Speed::Low);
+
+    loop {
+        info!("high");
+        led.set_high();
+        Timer::after(Duration::from_millis(300)).await;
+
+        info!("low");
+        led.set_low();
+        Timer::after(Duration::from_millis(300)).await;
+    }
+}
+
+#[embassy::main]
+async fn main(spawner: Spawner, p: Peripherals) {
+    info!("Hello Flash!");
+
+    let mut f = Flash::unlock(p.FLASH);
+
+    spawner.spawn(blinky(p.PB7.degrade())).unwrap();
+
+    // Sector 5
+    // test_flash(&mut f, 128 * 1024, 128 * 1024).await;
+
+    // Sectors 11..=16, across banks (128K, 16K, 16K, 16K, 16K, 64K)
+    // test_flash(&mut f, (1024 - 128) * 1024, 256 * 1024).await;
+
+    // Sectors 23, last in bank 2
+    test_flash(&mut f, (2048 - 128) * 1024, 128 * 1024).await;
+}
+
+async fn test_flash<'a>(f: &mut Flash<'a>, offset: u32, size: u32) {
+    info!("Testing offset: {=u32:#X}, size: {=u32:#X}", offset, size);
+
+    info!("Reading...");
+    let mut buf = [0u8; 32];
+    unwrap!(f.read(offset, &mut buf).await);
+    info!("Read: {=[u8]:x}", buf);
+
+    info!("Erasing...");
+    unwrap!(f.erase(offset, offset + size).await);
+
+    info!("Reading...");
+    let mut buf = [0u8; 32];
+    unwrap!(f.read(offset, &mut buf).await);
+    info!("Read after erase: {=[u8]:x}", buf);
+
+    info!("Writing...");
+    unwrap!(f.write(
+        offset,
+        &[
+            1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
+            30, 31, 32
+        ]
+    ).await);
+
+    info!("Reading...");
+    let mut buf = [0u8; 32];
+    unwrap!(f.read(offset, &mut buf).await);
+    info!("Read: {=[u8]:x}", buf);
+    assert_eq!(
+        &buf[..],
+        &[
+            1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
+            30, 31, 32
+        ]
+    );
+}