diff --git a/embassy-nrf/src/buffered_uarte.rs b/embassy-nrf/src/buffered_uarte.rs index 112f084c..79f9a1f7 100644 --- a/embassy-nrf/src/buffered_uarte.rs +++ b/embassy-nrf/src/buffered_uarte.rs @@ -1,10 +1,5 @@ //! Async buffered UART driver. //! -//! WARNING!!! The functionality provided here is intended to be used only -//! in situations where hardware flow control are available i.e. CTS and RTS. -//! This is a problem that should be addressed at a later stage and can be -//! fully explained at . -//! //! Note that discarding a future from a read or write operation may lead to losing //! data. For example, when using `futures_util::future::select` and completion occurs //! on the "other" future, you should capture the incomplete future and continue to use @@ -13,82 +8,120 @@ //! //! Please also see [crate::uarte] to understand when [BufferedUarte] should be used. -use core::cell::RefCell; use core::cmp::min; use core::future::poll_fn; -use core::sync::atomic::{compiler_fence, Ordering}; +use core::slice; +use core::sync::atomic::{compiler_fence, AtomicU8, AtomicUsize, Ordering}; use core::task::Poll; -use embassy_cortex_m::peripheral::{PeripheralMutex, PeripheralState, StateStorage}; -use embassy_hal_common::ring_buffer::RingBuffer; +use embassy_cortex_m::interrupt::Interrupt; +use embassy_hal_common::atomic_ring_buffer::RingBuffer; use embassy_hal_common::{into_ref, PeripheralRef}; -use embassy_sync::waitqueue::WakerRegistration; +use embassy_sync::waitqueue::AtomicWaker; // Re-export SVD variants to allow user to directly set values pub use pac::uarte0::{baudrate::BAUDRATE_A as Baudrate, config::PARITY_A as Parity}; -use crate::gpio::{self, Pin as GpioPin}; +use crate::gpio::sealed::Pin; +use crate::gpio::{self, AnyPin, Pin as GpioPin, PselBits}; use crate::interrupt::InterruptExt; -use crate::ppi::{AnyConfigurableChannel, ConfigurableChannel, Event, Ppi, Task}; -use crate::timer::{Frequency, Instance as TimerInstance, Timer}; +use crate::ppi::{ + self, AnyConfigurableChannel, AnyGroup, Channel, ConfigurableChannel, Event, Group, Ppi, PpiGroup, Task, +}; +use crate::timer::{Instance as TimerInstance, Timer}; use crate::uarte::{apply_workaround_for_enable_anomaly, Config, Instance as UarteInstance}; use crate::{pac, Peripheral}; -#[derive(Copy, Clone, Debug, PartialEq)] -enum RxState { - Idle, - Receiving, -} +mod sealed { + use super::*; -#[derive(Copy, Clone, Debug, PartialEq)] -enum TxState { - Idle, - Transmitting(usize), -} + pub struct State { + pub tx_waker: AtomicWaker, + pub tx_buf: RingBuffer, + pub tx_count: AtomicUsize, -/// A type for storing the state of the UARTE peripheral that can be stored in a static. -pub struct State<'d, U: UarteInstance, T: TimerInstance>(StateStorage>); -impl<'d, U: UarteInstance, T: TimerInstance> State<'d, U, T> { - /// Create an instance for storing UARTE peripheral state. - pub fn new() -> Self { - Self(StateStorage::new()) + pub rx_waker: AtomicWaker, + pub rx_buf: RingBuffer, + pub rx_bufs: AtomicU8, + pub rx_ppi_ch: AtomicU8, } } -struct StateInner<'d, U: UarteInstance, T: TimerInstance> { - _peri: PeripheralRef<'d, U>, - timer: Timer<'d, T>, - _ppi_ch1: Ppi<'d, AnyConfigurableChannel, 1, 2>, - _ppi_ch2: Ppi<'d, AnyConfigurableChannel, 1, 1>, +pub(crate) use sealed::State; - rx: RingBuffer<'d>, - rx_state: RxState, - rx_waker: WakerRegistration, +impl State { + pub(crate) const fn new() -> Self { + Self { + tx_waker: AtomicWaker::new(), + tx_buf: RingBuffer::new(), + tx_count: AtomicUsize::new(0), - tx: RingBuffer<'d>, - tx_state: TxState, - tx_waker: WakerRegistration, + rx_waker: AtomicWaker::new(), + rx_buf: RingBuffer::new(), + rx_bufs: AtomicU8::new(0), + rx_ppi_ch: AtomicU8::new(0), + } + } } /// Buffered UARTE driver. pub struct BufferedUarte<'d, U: UarteInstance, T: TimerInstance> { - inner: RefCell>>, + _peri: PeripheralRef<'d, U>, + timer: Timer<'d, T>, + _ppi_ch1: Ppi<'d, AnyConfigurableChannel, 1, 1>, + _ppi_ch2: Ppi<'d, AnyConfigurableChannel, 1, 2>, + _ppi_group: PpiGroup<'d, AnyGroup>, } impl<'d, U: UarteInstance, T: TimerInstance> Unpin for BufferedUarte<'d, U, T> {} impl<'d, U: UarteInstance, T: TimerInstance> BufferedUarte<'d, U, T> { - /// Create a new instance of a BufferedUarte. + /// Create a new BufferedUarte without hardware flow control. /// - /// See the [module documentation](crate::buffered_uarte) for more details about the intended use. + /// # Panics /// - /// The BufferedUarte uses the provided state to store the buffers and peripheral state. The timer and ppi channels are used to 'emulate' idle line detection so that read operations - /// can return early if there is no data to receive. + /// Panics if `rx_buffer.len()` is odd. pub fn new( - state: &'d mut State<'d, U, T>, - peri: impl Peripheral

+ 'd, + uarte: impl Peripheral

+ 'd, timer: impl Peripheral

+ 'd, - ppi_ch1: impl Peripheral

+ 'd, - ppi_ch2: impl Peripheral

+ 'd, + ppi_ch1: impl Peripheral

+ 'd, + ppi_ch2: impl Peripheral

+ 'd, + ppi_group: impl Peripheral

+ 'd, + irq: impl Peripheral

+ 'd, + rxd: impl Peripheral

+ 'd, + txd: impl Peripheral

+ 'd, + config: Config, + rx_buffer: &'d mut [u8], + tx_buffer: &'d mut [u8], + ) -> Self { + into_ref!(rxd, txd, ppi_ch1, ppi_ch2, ppi_group); + Self::new_inner( + uarte, + timer, + ppi_ch1.map_into(), + ppi_ch2.map_into(), + ppi_group.map_into(), + irq, + rxd.map_into(), + txd.map_into(), + None, + None, + config, + rx_buffer, + tx_buffer, + ) + } + + /// Create a new BufferedUarte with hardware flow control (RTS/CTS) + /// + /// # Panics + /// + /// Panics if `rx_buffer.len()` is odd. + pub fn new_with_rtscts( + uarte: impl Peripheral

+ 'd, + timer: impl Peripheral

+ 'd, + ppi_ch1: impl Peripheral

+ 'd, + ppi_ch2: impl Peripheral

+ 'd, + ppi_group: impl Peripheral

+ 'd, irq: impl Peripheral

+ 'd, rxd: impl Peripheral

+ 'd, txd: impl Peripheral

+ 'd, @@ -98,12 +131,45 @@ impl<'d, U: UarteInstance, T: TimerInstance> BufferedUarte<'d, U, T> { rx_buffer: &'d mut [u8], tx_buffer: &'d mut [u8], ) -> Self { - into_ref!(peri, ppi_ch1, ppi_ch2, irq, rxd, txd, cts, rts); + into_ref!(rxd, txd, cts, rts, ppi_ch1, ppi_ch2, ppi_group); + Self::new_inner( + uarte, + timer, + ppi_ch1.map_into(), + ppi_ch2.map_into(), + ppi_group.map_into(), + irq, + rxd.map_into(), + txd.map_into(), + Some(cts.map_into()), + Some(rts.map_into()), + config, + rx_buffer, + tx_buffer, + ) + } + + fn new_inner( + peri: impl Peripheral

+ 'd, + timer: impl Peripheral

+ 'd, + ppi_ch1: PeripheralRef<'d, AnyConfigurableChannel>, + ppi_ch2: PeripheralRef<'d, AnyConfigurableChannel>, + ppi_group: PeripheralRef<'d, AnyGroup>, + irq: impl Peripheral

+ 'd, + rxd: PeripheralRef<'d, AnyPin>, + txd: PeripheralRef<'d, AnyPin>, + cts: Option>, + rts: Option>, + config: Config, + rx_buffer: &'d mut [u8], + tx_buffer: &'d mut [u8], + ) -> Self { + into_ref!(peri, timer, irq); + + assert!(rx_buffer.len() % 2 == 0); let r = U::regs(); - let mut timer = Timer::new(timer); - rxd.conf().write(|w| w.input().connect().drive().h0h1()); r.psel.rxd.write(|w| unsafe { w.bits(rxd.psel_bits()) }); @@ -111,92 +177,200 @@ impl<'d, U: UarteInstance, T: TimerInstance> BufferedUarte<'d, U, T> { txd.conf().write(|w| w.dir().output().drive().h0h1()); r.psel.txd.write(|w| unsafe { w.bits(txd.psel_bits()) }); - cts.conf().write(|w| w.input().connect().drive().h0h1()); + if let Some(pin) = &cts { + pin.conf().write(|w| w.input().connect().drive().h0h1()); + } r.psel.cts.write(|w| unsafe { w.bits(cts.psel_bits()) }); - rts.set_high(); - rts.conf().write(|w| w.dir().output().drive().h0h1()); + if let Some(pin) = &rts { + pin.set_high(); + pin.conf().write(|w| w.dir().output().drive().h0h1()); + } r.psel.rts.write(|w| unsafe { w.bits(rts.psel_bits()) }); - r.baudrate.write(|w| w.baudrate().variant(config.baudrate)); - r.config.write(|w| w.parity().variant(config.parity)); + // Initialize state + let s = U::buffered_state(); + s.tx_count.store(0, Ordering::Relaxed); + s.rx_bufs.store(0, Ordering::Relaxed); + let len = tx_buffer.len(); + unsafe { s.tx_buf.init(tx_buffer.as_mut_ptr(), len) }; + let len = rx_buffer.len(); + unsafe { s.rx_buf.init(rx_buffer.as_mut_ptr(), len) }; // Configure r.config.write(|w| { - w.hwfc().bit(true); + w.hwfc().bit(false); w.parity().variant(config.parity); w }); r.baudrate.write(|w| w.baudrate().variant(config.baudrate)); - // Enable interrupts - r.intenset.write(|w| w.endrx().set().endtx().set()); + // clear errors + let errors = r.errorsrc.read().bits(); + r.errorsrc.write(|w| unsafe { w.bits(errors) }); - // Disable the irq, let the Registration enable it when everything is set up. - irq.disable(); - irq.pend(); + r.events_rxstarted.reset(); + r.events_txstarted.reset(); + r.events_error.reset(); + r.events_endrx.reset(); + r.events_endtx.reset(); + + // Enable interrupts + r.intenclr.write(|w| unsafe { w.bits(!0) }); + r.intenset.write(|w| { + w.endtx().set(); + w.rxstarted().set(); + w.error().set(); + w + }); // Enable UARTE instance apply_workaround_for_enable_anomaly(&r); r.enable.write(|w| w.enable().enabled()); - // BAUDRATE register values are `baudrate * 2^32 / 16000000` - // source: https://devzone.nordicsemi.com/f/nordic-q-a/391/uart-baudrate-register-values - // - // We want to stop RX if line is idle for 2 bytes worth of time - // That is 20 bits (each byte is 1 start bit + 8 data bits + 1 stop bit) - // This gives us the amount of 16M ticks for 20 bits. - let timeout = 0x8000_0000 / (config.baudrate as u32 / 40); + // Configure byte counter. + let mut timer = Timer::new_counter(timer); + timer.cc(1).write(rx_buffer.len() as u32 * 2); + timer.cc(1).short_compare_clear(); + timer.clear(); + timer.start(); - timer.set_frequency(Frequency::F16MHz); - timer.cc(0).write(timeout); - timer.cc(0).short_compare_clear(); - timer.cc(0).short_compare_stop(); - - let mut ppi_ch1 = Ppi::new_one_to_two( - ppi_ch1.map_into(), - Event::from_reg(&r.events_rxdrdy), - timer.task_clear(), - timer.task_start(), - ); + let mut ppi_ch1 = Ppi::new_one_to_one(ppi_ch1, Event::from_reg(&r.events_rxdrdy), timer.task_count()); ppi_ch1.enable(); - let mut ppi_ch2 = Ppi::new_one_to_one( - ppi_ch2.map_into(), - timer.cc(0).event_compare(), - Task::from_reg(&r.tasks_stoprx), + s.rx_ppi_ch.store(ppi_ch2.number() as u8, Ordering::Relaxed); + let mut ppi_group = PpiGroup::new(ppi_group); + let mut ppi_ch2 = Ppi::new_one_to_two( + ppi_ch2, + Event::from_reg(&r.events_endrx), + Task::from_reg(&r.tasks_startrx), + ppi_group.task_disable_all(), ); - ppi_ch2.enable(); + ppi_ch2.disable(); + ppi_group.add_channel(&ppi_ch2); + + irq.disable(); + irq.set_handler(Self::on_interrupt); + irq.pend(); + irq.enable(); Self { - inner: RefCell::new(PeripheralMutex::new(irq, &mut state.0, move || StateInner { - _peri: peri, - timer, - _ppi_ch1: ppi_ch1, - _ppi_ch2: ppi_ch2, - - rx: RingBuffer::new(rx_buffer), - rx_state: RxState::Idle, - rx_waker: WakerRegistration::new(), - - tx: RingBuffer::new(tx_buffer), - tx_state: TxState::Idle, - tx_waker: WakerRegistration::new(), - })), + _peri: peri, + timer, + _ppi_ch1: ppi_ch1, + _ppi_ch2: ppi_ch2, + _ppi_group: ppi_group, } } + fn pend_irq() { + unsafe { ::steal() }.pend() + } + + fn on_interrupt(_: *mut ()) { + //trace!("irq: start"); + let r = U::regs(); + let s = U::buffered_state(); + + let buf_len = s.rx_buf.len(); + let half_len = buf_len / 2; + let mut tx = unsafe { s.tx_buf.reader() }; + let mut rx = unsafe { s.rx_buf.writer() }; + + if r.events_error.read().bits() != 0 { + r.events_error.reset(); + let errs = r.errorsrc.read(); + r.errorsrc.write(|w| unsafe { w.bits(errs.bits()) }); + + if errs.overrun().bit() { + panic!("BufferedUarte overrun"); + } + } + + // Received some bytes, wake task. + if r.inten.read().rxdrdy().bit_is_set() && r.events_rxdrdy.read().events_rxdrdy().bit_is_set() { + r.intenclr.write(|w| w.rxdrdy().clear()); + r.events_rxdrdy.reset(); + s.rx_waker.wake(); + } + + // If not RXing, start. + if s.rx_bufs.load(Ordering::Relaxed) == 0 { + let (ptr, len) = rx.push_buf(); + if len >= half_len { + //trace!(" irq_rx: starting {:?}", half_len); + s.rx_bufs.store(1, Ordering::Relaxed); + + // Set up the DMA read + r.rxd.ptr.write(|w| unsafe { w.ptr().bits(ptr as u32) }); + r.rxd.maxcnt.write(|w| unsafe { w.maxcnt().bits(half_len as _) }); + + // Start UARTE Receive transaction + r.tasks_startrx.write(|w| unsafe { w.bits(1) }); + rx.push_done(half_len); + r.intenset.write(|w| w.rxstarted().set()); + } + } + + if r.events_rxstarted.read().bits() != 0 { + //trace!(" irq_rx: rxstarted"); + let (ptr, len) = rx.push_buf(); + if len >= half_len { + //trace!(" irq_rx: starting second {:?}", half_len); + + // Set up the DMA read + r.rxd.ptr.write(|w| unsafe { w.ptr().bits(ptr as u32) }); + r.rxd.maxcnt.write(|w| unsafe { w.maxcnt().bits(half_len as _) }); + + let chn = s.rx_ppi_ch.load(Ordering::Relaxed); + + ppi::regs().chenset.write(|w| unsafe { w.bits(1 << chn) }); + + rx.push_done(half_len); + + r.events_rxstarted.reset(); + } else { + //trace!(" irq_rx: rxstarted no buf"); + r.intenclr.write(|w| w.rxstarted().clear()); + } + } + + // ============================= + + // TX end + if r.events_endtx.read().bits() != 0 { + r.events_endtx.reset(); + + let n = s.tx_count.load(Ordering::Relaxed); + //trace!(" irq_tx: endtx {:?}", n); + tx.pop_done(n); + s.tx_waker.wake(); + s.tx_count.store(0, Ordering::Relaxed); + } + + // If not TXing, start. + if s.tx_count.load(Ordering::Relaxed) == 0 { + let (ptr, len) = tx.pop_buf(); + if len != 0 { + //trace!(" irq_tx: starting {:?}", len); + s.tx_count.store(len, Ordering::Relaxed); + + // Set up the DMA write + r.txd.ptr.write(|w| unsafe { w.ptr().bits(ptr as u32) }); + r.txd.maxcnt.write(|w| unsafe { w.maxcnt().bits(len as _) }); + + // Start UARTE Transmit transaction + r.tasks_starttx.write(|w| unsafe { w.bits(1) }); + } + } + + //trace!("irq: end"); + } + /// Adjust the baud rate to the provided value. pub fn set_baudrate(&mut self, baudrate: Baudrate) { - self.inner.borrow_mut().with(|state| { - let r = U::regs(); - - let timeout = 0x8000_0000 / (baudrate as u32 / 40); - state.timer.cc(0).write(timeout); - state.timer.clear(); - - r.baudrate.write(|w| w.baudrate().variant(baudrate)); - }); + let r = U::regs(); + r.baudrate.write(|w| w.baudrate().variant(baudrate)); } /// Split the UART in reader and writer parts. @@ -206,120 +380,117 @@ impl<'d, U: UarteInstance, T: TimerInstance> BufferedUarte<'d, U, T> { (BufferedUarteRx { inner: self }, BufferedUarteTx { inner: self }) } - async fn inner_read<'a>(&'a self, buf: &'a mut [u8]) -> Result { - poll_fn(move |cx| { - let mut do_pend = false; - let mut inner = self.inner.borrow_mut(); - let res = inner.with(|state| { - compiler_fence(Ordering::SeqCst); - trace!("poll_read"); - - // We have data ready in buffer? Return it. - let data = state.rx.pop_buf(); - if !data.is_empty() { - trace!(" got {:?} {:?}", data.as_ptr() as u32, data.len()); - let len = data.len().min(buf.len()); - buf[..len].copy_from_slice(&data[..len]); - state.rx.pop(len); - do_pend = true; - return Poll::Ready(Ok(len)); - } - - trace!(" empty"); - state.rx_waker.register(cx.waker()); - Poll::Pending - }); - if do_pend { - inner.pend(); - } - - res - }) - .await + async fn inner_read(&self, buf: &mut [u8]) -> Result { + let data = self.inner_fill_buf().await?; + let n = data.len().min(buf.len()); + buf[..n].copy_from_slice(&data[..n]); + self.inner_consume(n); + Ok(n) } async fn inner_write<'a>(&'a self, buf: &'a [u8]) -> Result { poll_fn(move |cx| { - let mut inner = self.inner.borrow_mut(); - let res = inner.with(|state| { - trace!("poll_write: {:?}", buf.len()); + //trace!("poll_write: {:?}", buf.len()); + let s = U::buffered_state(); + let mut tx = unsafe { s.tx_buf.writer() }; - let tx_buf = state.tx.push_buf(); - if tx_buf.is_empty() { - trace!("poll_write: pending"); - state.tx_waker.register(cx.waker()); - return Poll::Pending; - } + let tx_buf = tx.push_slice(); + if tx_buf.is_empty() { + //trace!("poll_write: pending"); + s.tx_waker.register(cx.waker()); + return Poll::Pending; + } - let n = min(tx_buf.len(), buf.len()); - tx_buf[..n].copy_from_slice(&buf[..n]); - state.tx.push(n); + let n = min(tx_buf.len(), buf.len()); + tx_buf[..n].copy_from_slice(&buf[..n]); + tx.push_done(n); - trace!("poll_write: queued {:?}", n); + //trace!("poll_write: queued {:?}", n); - compiler_fence(Ordering::SeqCst); + compiler_fence(Ordering::SeqCst); + Self::pend_irq(); - Poll::Ready(Ok(n)) - }); - - inner.pend(); - - res + Poll::Ready(Ok(n)) }) .await } async fn inner_flush<'a>(&'a self) -> Result<(), core::convert::Infallible> { poll_fn(move |cx| { - self.inner.borrow_mut().with(|state| { - trace!("poll_flush"); + //trace!("poll_flush"); + let s = U::buffered_state(); + if !s.tx_buf.is_empty() { + //trace!("poll_flush: pending"); + s.tx_waker.register(cx.waker()); + return Poll::Pending; + } - if !state.tx.is_empty() { - trace!("poll_flush: pending"); - state.tx_waker.register(cx.waker()); - return Poll::Pending; - } - - Poll::Ready(Ok(())) - }) + Poll::Ready(Ok(())) }) .await } async fn inner_fill_buf<'a>(&'a self) -> Result<&'a [u8], core::convert::Infallible> { poll_fn(move |cx| { - self.inner.borrow_mut().with(|state| { - compiler_fence(Ordering::SeqCst); - trace!("fill_buf"); + compiler_fence(Ordering::SeqCst); + //trace!("poll_read"); - // We have data ready in buffer? Return it. - let buf = state.rx.pop_buf(); - if !buf.is_empty() { - trace!(" got {:?} {:?}", buf.as_ptr() as u32, buf.len()); - let buf: &[u8] = buf; - // Safety: buffer lives as long as uart - let buf: &[u8] = unsafe { core::mem::transmute(buf) }; - return Poll::Ready(Ok(buf)); - } + let r = U::regs(); + let s = U::buffered_state(); - trace!(" empty"); - state.rx_waker.register(cx.waker()); - Poll::>::Pending - }) + // Read the RXDRDY counter. + T::regs().tasks_capture[0].write(|w| unsafe { w.bits(1) }); + let mut end = T::regs().cc[0].read().bits() as usize; + //trace!(" rxdrdy count = {:?}", end); + + // We've set a compare channel that resets the counter to 0 when it reaches `len*2`. + // However, it's unclear if that's instant, or there's a small window where you can + // still read `len()*2`. + // This could happen if in one clock cycle the counter is updated, and in the next the + // clear takes effect. The docs are very sparse, they just say "Task delays: After TIMER + // is started, the CLEAR, COUNT, and STOP tasks are guaranteed to take effect within one + // clock cycle of the PCLK16M." :shrug: + // So, we wrap the counter ourselves, just in case. + if end > s.rx_buf.len() * 2 { + end = 0 + } + + // This logic mirrors `atomic_ring_buffer::Reader::pop_buf()` + let mut start = s.rx_buf.start.load(Ordering::Relaxed); + let len = s.rx_buf.len(); + if start == end { + //trace!(" empty"); + s.rx_waker.register(cx.waker()); + r.intenset.write(|w| w.rxdrdy().set_bit()); + return Poll::Pending; + } + + if start >= len { + start -= len + } + if end >= len { + end -= len + } + + let n = if end > start { end - start } else { len - start }; + assert!(n != 0); + //trace!(" uarte ringbuf: pop_buf {:?}..{:?}", start, start + n); + + let buf = s.rx_buf.buf.load(Ordering::Relaxed); + Poll::Ready(Ok(unsafe { slice::from_raw_parts(buf.add(start), n) })) }) .await } fn inner_consume(&self, amt: usize) { - let mut inner = self.inner.borrow_mut(); - let signal = inner.with(|state| { - let full = state.rx.is_full(); - state.rx.pop(amt); - full - }); - if signal { - inner.pend(); + if amt == 0 { + return; } + + let s = U::buffered_state(); + let mut rx = unsafe { s.rx_buf.reader() }; + rx.pop_done(amt); + U::regs().intenset.write(|w| w.rxstarted().set()); } } @@ -397,7 +568,7 @@ impl<'u, 'd: 'u, U: UarteInstance, T: TimerInstance> embedded_io::asynch::Write } } -impl<'a, U: UarteInstance, T: TimerInstance> Drop for StateInner<'a, U, T> { +impl<'a, U: UarteInstance, T: TimerInstance> Drop for BufferedUarte<'a, U, T> { fn drop(&mut self) { let r = U::regs(); @@ -418,108 +589,11 @@ impl<'a, U: UarteInstance, T: TimerInstance> Drop for StateInner<'a, U, T> { gpio::deconfigure_pin(r.psel.txd.read().bits()); gpio::deconfigure_pin(r.psel.rts.read().bits()); gpio::deconfigure_pin(r.psel.cts.read().bits()); - } -} - -impl<'a, U: UarteInstance, T: TimerInstance> PeripheralState for StateInner<'a, U, T> { - type Interrupt = U::Interrupt; - fn on_interrupt(&mut self) { - trace!("irq: start"); - let r = U::regs(); - - loop { - match self.rx_state { - RxState::Idle => { - trace!(" irq_rx: in state idle"); - - let buf = self.rx.push_buf(); - if !buf.is_empty() { - trace!(" irq_rx: starting {:?}", buf.len()); - self.rx_state = RxState::Receiving; - - // Set up the DMA read - r.rxd.ptr.write(|w| - // The PTR field is a full 32 bits wide and accepts the full range - // of values. - unsafe { w.ptr().bits(buf.as_ptr() as u32) }); - r.rxd.maxcnt.write(|w| - // We're giving it the length of the buffer, so no danger of - // accessing invalid memory. We have verified that the length of the - // buffer fits in an `u8`, so the cast to `u8` is also fine. - // - // The MAXCNT field is at least 8 bits wide and accepts the full - // range of values. - unsafe { w.maxcnt().bits(buf.len() as _) }); - trace!(" irq_rx: buf {:?} {:?}", buf.as_ptr() as u32, buf.len()); - - // Start UARTE Receive transaction - r.tasks_startrx.write(|w| unsafe { w.bits(1) }); - } - break; - } - RxState::Receiving => { - trace!(" irq_rx: in state receiving"); - if r.events_endrx.read().bits() != 0 { - self.timer.stop(); - - let n: usize = r.rxd.amount.read().amount().bits() as usize; - trace!(" irq_rx: endrx {:?}", n); - self.rx.push(n); - - r.events_endrx.reset(); - - self.rx_waker.wake(); - self.rx_state = RxState::Idle; - } else { - break; - } - } - } - } - - loop { - match self.tx_state { - TxState::Idle => { - trace!(" irq_tx: in state Idle"); - let buf = self.tx.pop_buf(); - if !buf.is_empty() { - trace!(" irq_tx: starting {:?}", buf.len()); - self.tx_state = TxState::Transmitting(buf.len()); - - // Set up the DMA write - r.txd.ptr.write(|w| - // The PTR field is a full 32 bits wide and accepts the full range - // of values. - unsafe { w.ptr().bits(buf.as_ptr() as u32) }); - r.txd.maxcnt.write(|w| - // We're giving it the length of the buffer, so no danger of - // accessing invalid memory. We have verified that the length of the - // buffer fits in an `u8`, so the cast to `u8` is also fine. - // - // The MAXCNT field is 8 bits wide and accepts the full range of - // values. - unsafe { w.maxcnt().bits(buf.len() as _) }); - - // Start UARTE Transmit transaction - r.tasks_starttx.write(|w| unsafe { w.bits(1) }); - } - break; - } - TxState::Transmitting(n) => { - trace!(" irq_tx: in state Transmitting"); - if r.events_endtx.read().bits() != 0 { - r.events_endtx.reset(); - - trace!(" irq_tx: endtx {:?}", n); - self.tx.pop(n); - self.tx_waker.wake(); - self.tx_state = TxState::Idle; - } else { - break; - } - } - } - } - trace!("irq: end"); + + let s = U::buffered_state(); + unsafe { + s.rx_buf.deinit(); + s.tx_buf.deinit(); + } } } diff --git a/embassy-nrf/src/uarte.rs b/embassy-nrf/src/uarte.rs index 48457744..00afbd05 100644 --- a/embassy-nrf/src/uarte.rs +++ b/embassy-nrf/src/uarte.rs @@ -883,6 +883,7 @@ pub(crate) mod sealed { pub trait Instance { fn regs() -> &'static pac::uarte0::RegisterBlock; fn state() -> &'static State; + fn buffered_state() -> &'static crate::buffered_uarte::State; } } @@ -902,6 +903,10 @@ macro_rules! impl_uarte { static STATE: crate::uarte::sealed::State = crate::uarte::sealed::State::new(); &STATE } + fn buffered_state() -> &'static crate::buffered_uarte::State { + static STATE: crate::buffered_uarte::State = crate::buffered_uarte::State::new(); + &STATE + } } impl crate::uarte::Instance for peripherals::$type { type Interrupt = crate::interrupt::$irq; diff --git a/examples/nrf52840/src/bin/buffered_uart.rs b/examples/nrf52840/src/bin/buffered_uart.rs index ea566f4b..584e6b2b 100644 --- a/examples/nrf52840/src/bin/buffered_uart.rs +++ b/examples/nrf52840/src/bin/buffered_uart.rs @@ -4,10 +4,9 @@ use defmt::*; use embassy_executor::Spawner; -use embassy_nrf::buffered_uarte::{BufferedUarte, State}; +use embassy_nrf::buffered_uarte::BufferedUarte; use embassy_nrf::{interrupt, uarte}; use embedded_io::asynch::{BufRead, Write}; -use futures::pin_mut; use {defmt_rtt as _, panic_probe as _}; #[embassy_executor::main] @@ -21,24 +20,19 @@ async fn main(_spawner: Spawner) { let mut rx_buffer = [0u8; 4096]; let irq = interrupt::take!(UARTE0_UART0); - let mut state = State::new(); - // Please note - important to have hardware flow control (https://github.com/embassy-rs/embassy/issues/536) - let u = BufferedUarte::new( - &mut state, + let mut u = BufferedUarte::new( p.UARTE0, p.TIMER0, p.PPI_CH0, p.PPI_CH1, + p.PPI_GROUP0, irq, p.P0_08, p.P0_06, - p.P0_07, - p.P0_05, config, &mut rx_buffer, &mut tx_buffer, ); - pin_mut!(u); info!("uarte initialized!");