Support overflow detection for more than one ring-period
This commit is contained in:
parent
4ea6662e55
commit
fc268df6f5
@ -4,6 +4,7 @@ use core::pin::Pin;
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use core::sync::atomic::{fence, Ordering};
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use core::task::{Context, Poll, Waker};
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use atomic_polyfill::AtomicUsize;
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use embassy_cortex_m::interrupt::Priority;
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use embassy_hal_common::{into_ref, Peripheral, PeripheralRef};
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use embassy_sync::waitqueue::AtomicWaker;
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@ -129,13 +130,16 @@ impl From<FifoThreshold> for vals::Fth {
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struct State {
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ch_wakers: [AtomicWaker; DMA_CHANNEL_COUNT],
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complete_count: [AtomicUsize; DMA_CHANNEL_COUNT],
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}
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impl State {
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const fn new() -> Self {
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const ZERO: AtomicUsize = AtomicUsize::new(0);
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const AW: AtomicWaker = AtomicWaker::new();
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Self {
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ch_wakers: [AW; DMA_CHANNEL_COUNT],
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complete_count: [ZERO; DMA_CHANNEL_COUNT],
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}
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}
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}
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@ -184,13 +188,43 @@ pub(crate) unsafe fn on_irq_inner(dma: pac::dma::Dma, channel_num: usize, index:
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panic!("DMA: error on DMA@{:08x} channel {}", dma.0 as u32, channel_num);
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}
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if isr.tcif(channel_num % 4) && cr.read().tcie() {
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/* acknowledge transfer complete interrupt */
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dma.ifcr(channel_num / 4).write(|w| w.set_tcif(channel_num % 4, true));
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let mut wake = false;
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if isr.htif(channel_num % 4) && cr.read().htie() {
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// Acknowledge half transfer complete interrupt
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dma.ifcr(channel_num / 4).write(|w| w.set_htif(channel_num % 4, true));
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wake = true;
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}
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wake |= process_tcif(dma, channel_num, index);
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if wake {
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STATE.ch_wakers[index].wake();
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}
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}
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unsafe fn process_tcif(dma: pac::dma::Dma, channel_num: usize, index: usize) -> bool {
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let isr_reg = dma.isr(channel_num / 4);
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let cr_reg = dma.st(channel_num).cr();
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// First, figure out if tcif is set without a cs.
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if isr_reg.read().tcif(channel_num % 4) && cr_reg.read().tcie() {
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// Make tcif test again within a cs to avoid race when incrementing complete_count.
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critical_section::with(|_| {
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if isr_reg.read().tcif(channel_num % 4) && cr_reg.read().tcie() {
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// Acknowledge transfer complete interrupt
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dma.ifcr(channel_num / 4).write(|w| w.set_tcif(channel_num % 4, true));
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STATE.complete_count[index].fetch_add(1, Ordering::Release);
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true
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} else {
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false
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}
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})
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} else {
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false
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}
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}
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#[cfg(any(dma_v2, dmamux))]
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pub type Request = u8;
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#[cfg(not(any(dma_v2, dmamux)))]
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@ -530,6 +564,7 @@ impl<'a, C: Channel, W: Word> DoubleBuffered<'a, C, W> {
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unsafe {
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dma.ifcr(isrn).write(|w| {
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w.set_htif(isrbit, true);
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w.set_tcif(isrbit, true);
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w.set_teif(isrbit, true);
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})
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@ -593,32 +628,28 @@ impl<'a, C: Channel, W: Word> Drop for DoubleBuffered<'a, C, W> {
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// ==============================
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impl<C: Channel> DmaCtrl for C {
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fn tcif(&self) -> bool {
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let channel_number = self.num();
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let dma = self.regs();
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let isrn = channel_number / 4;
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let isrbit = channel_number % 4;
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unsafe { dma.isr(isrn).read() }.tcif(isrbit)
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}
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fn clear_tcif(&mut self) {
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let channel_number = self.num();
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let dma = self.regs();
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let isrn = channel_number / 4;
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let isrbit = channel_number % 4;
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unsafe {
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dma.ifcr(isrn).write(|w| {
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w.set_tcif(isrbit, true);
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})
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}
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}
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fn ndtr(&self) -> usize {
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let ch = self.regs().st(self.num());
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unsafe { ch.ndtr().read() }.ndt() as usize
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}
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fn get_complete_count(&self) -> usize {
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let dma = self.regs();
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let channel_num = self.num();
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let index = self.index();
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// Manually process tcif in case transfer was completed and we are in a higher priority task.
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unsafe { process_tcif(dma, channel_num, index) };
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STATE.complete_count[index].load(Ordering::Acquire)
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}
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fn reset_complete_count(&mut self) -> usize {
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let dma = self.regs();
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let channel_num = self.num();
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let index = self.index();
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// Manually process tcif in case transfer was completed and we are in a higher priority task.
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unsafe { process_tcif(dma, channel_num, index) };
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STATE.complete_count[index].swap(0, Ordering::AcqRel)
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}
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}
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pub struct RingBuffer<'a, C: Channel, W: Word> {
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@ -657,7 +688,8 @@ impl<'a, C: Channel, W: Word> RingBuffer<'a, C, W> {
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w.set_minc(vals::Inc::INCREMENTED);
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w.set_pinc(vals::Inc::FIXED);
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w.set_teie(true);
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w.set_tcie(false);
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w.set_htie(true);
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w.set_tcie(true);
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w.set_circ(vals::Circ::ENABLED);
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#[cfg(dma_v1)]
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w.set_trbuff(true);
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@ -703,7 +735,7 @@ impl<'a, C: Channel, W: Word> RingBuffer<'a, C, W> {
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}
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pub fn clear(&mut self) {
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self.ringbuf.clear();
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self.ringbuf.clear(&mut *self.channel);
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}
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/// Read bytes from the ring buffer
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@ -712,6 +744,22 @@ impl<'a, C: Channel, W: Word> RingBuffer<'a, C, W> {
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self.ringbuf.read(&mut *self.channel, buf)
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}
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pub fn is_empty(&self) -> bool {
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self.ringbuf.is_empty()
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}
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pub fn len(&self) -> usize {
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self.ringbuf.len()
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}
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pub fn capacity(&self) -> usize {
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self.ringbuf.dma_buf.len()
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}
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pub fn set_waker(&mut self, waker: &Waker) {
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STATE.ch_wakers[self.channel.index()].register(waker);
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}
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fn clear_irqs(&mut self) {
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let channel_number = self.channel.num();
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let dma = self.channel.regs();
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@ -720,6 +768,7 @@ impl<'a, C: Channel, W: Word> RingBuffer<'a, C, W> {
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unsafe {
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dma.ifcr(isrn).write(|w| {
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w.set_htif(isrbit, true);
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w.set_tcif(isrbit, true);
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w.set_teif(isrbit, true);
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})
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@ -733,6 +782,7 @@ impl<'a, C: Channel, W: Word> RingBuffer<'a, C, W> {
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unsafe {
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ch.cr().write(|w| {
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w.set_teie(true);
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w.set_htie(true);
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w.set_tcie(true);
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})
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}
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@ -743,15 +793,10 @@ impl<'a, C: Channel, W: Word> RingBuffer<'a, C, W> {
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unsafe { ch.cr().read() }.en()
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}
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/// Gets the total remaining transfers for the channel
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/// Note: this will be zero for transfers that completed without cancellation.
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pub fn get_remaining_transfers(&self) -> usize {
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/// Synchronize the position of the ring buffer to the actual DMA controller position
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pub fn reload_position(&mut self) {
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let ch = self.channel.regs().st(self.channel.num());
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unsafe { ch.ndtr().read() }.ndt() as usize
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}
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pub fn set_ndtr(&mut self, ndtr: usize) {
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self.ringbuf.ndtr = ndtr;
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self.ringbuf.ndtr = unsafe { ch.ndtr().read() }.ndt() as usize;
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}
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}
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@ -10,14 +10,6 @@ use super::word::Word;
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/// to the current register value. `ndtr` describes the current position of the DMA
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/// write.
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///
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/// # Safety
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///
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/// The ring buffer controls the TCIF (transfer completed interrupt flag) to
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/// detect buffer overruns, hence this interrupt must be disabled.
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/// The buffer can detect overruns up to one period, that is, for a X byte buffer,
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/// overruns can be detected if they happen from byte X+1 up to 2X. After this
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/// point, overrunds may or may not be detected.
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///
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/// # Buffer layout
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///
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/// ```text
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@ -39,7 +31,6 @@ pub struct DmaRingBuffer<'a, W: Word> {
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pub(crate) dma_buf: &'a mut [W],
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first: usize,
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pub ndtr: usize,
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expect_next_read_to_wrap: bool,
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}
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#[derive(Debug, PartialEq)]
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@ -50,13 +41,13 @@ pub trait DmaCtrl {
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/// buffer until the dma writer wraps.
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fn ndtr(&self) -> usize;
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/// Read the transfer completed interrupt flag
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/// This flag is set by the dma controller when NDTR is reloaded,
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/// Get the transfer completed counter.
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/// This counter is incremented by the dma controller when NDTR is reloaded,
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/// i.e. when the writing wraps.
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fn tcif(&self) -> bool;
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fn get_complete_count(&self) -> usize;
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/// Clear the transfer completed interrupt flag
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fn clear_tcif(&mut self);
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/// Reset the transfer completed counter to 0 and return the value just prior to the reset.
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fn reset_complete_count(&mut self) -> usize;
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}
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impl<'a, W: Word> DmaRingBuffer<'a, W> {
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@ -66,15 +57,14 @@ impl<'a, W: Word> DmaRingBuffer<'a, W> {
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dma_buf,
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first: 0,
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ndtr,
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expect_next_read_to_wrap: false,
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}
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}
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/// Reset the ring buffer to its initial state
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pub fn clear(&mut self) {
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pub fn clear(&mut self, dma: &mut impl DmaCtrl) {
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self.first = 0;
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self.ndtr = self.dma_buf.len();
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self.expect_next_read_to_wrap = false;
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dma.reset_complete_count();
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}
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/// The buffer end position
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@ -83,14 +73,12 @@ impl<'a, W: Word> DmaRingBuffer<'a, W> {
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}
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/// Returns whether the buffer is empty
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#[allow(dead_code)]
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pub fn is_empty(&self) -> bool {
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self.first == self.end()
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}
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/// The current number of bytes in the buffer
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/// This may change at any time if dma is currently active
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#[allow(dead_code)]
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pub fn len(&self) -> usize {
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// Read out a stable end (the dma periheral can change it at anytime)
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let end = self.end();
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@ -112,27 +100,19 @@ impl<'a, W: Word> DmaRingBuffer<'a, W> {
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if self.first == end {
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// The buffer is currently empty
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if dma.tcif() {
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// The dma controller has written such that the ring buffer now wraps
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// This is the special case where exactly n*dma_buf.len(), n = 1,2,..., bytes was written,
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// but where additional bytes are now written causing the ring buffer to wrap.
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// This is only an error if the writing has passed the current unread region.
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if dma.get_complete_count() > 0 {
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// The DMA has written such that the ring buffer wraps at least once
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self.ndtr = dma.ndtr();
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if self.end() > self.first {
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dma.clear_tcif();
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if self.end() > self.first || dma.get_complete_count() > 1 {
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return Err(OverrunError);
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}
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}
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self.expect_next_read_to_wrap = false;
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Ok(0)
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} else if self.first < end {
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// The available, unread portion in the ring buffer DOES NOT wrap
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if self.expect_next_read_to_wrap {
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// The read was expected to wrap but it did not
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dma.clear_tcif();
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if dma.get_complete_count() > 1 {
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return Err(OverrunError);
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}
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@ -141,35 +121,39 @@ impl<'a, W: Word> DmaRingBuffer<'a, W> {
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compiler_fence(Ordering::SeqCst);
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if dma.tcif() {
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// The dma controller has written such that the ring buffer now wraps
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match dma.get_complete_count() {
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0 => {
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// The DMA writer has not wrapped before nor after the copy
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}
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1 => {
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// The DMA writer has written such that the ring buffer now wraps
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self.ndtr = dma.ndtr();
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if self.end() > self.first {
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if self.end() > self.first || dma.get_complete_count() > 1 {
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// The bytes that we have copied out have overflowed
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// as the writer has now both wrapped and is currently writing
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// within the region that we have just copied out
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// Clear transfer completed interrupt flag
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dma.clear_tcif();
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return Err(OverrunError);
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}
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}
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_ => {
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return Err(OverrunError);
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}
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}
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self.first = (self.first + len) % self.dma_buf.len();
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self.expect_next_read_to_wrap = false;
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Ok(len)
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} else {
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// The available, unread portion in the ring buffer DOES wrap
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// The dma controller has wrapped since we last read and is currently
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// The DMA writer has wrapped since we last read and is currently
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// writing (or the next byte added will be) in the beginning of the ring buffer.
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// If the unread portion wraps then the writer must also have wrapped,
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// or it has wrapped and we already cleared the TCIF flag
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assert!(dma.tcif() || self.expect_next_read_to_wrap);
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let complete_count = dma.get_complete_count();
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if complete_count > 1 {
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return Err(OverrunError);
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}
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// Clear transfer completed interrupt flag
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dma.clear_tcif();
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// If the unread portion wraps then the writer must also have wrapped
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assert!(complete_count == 1);
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if self.first + buf.len() < self.dma_buf.len() {
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// The provided read buffer is not large enough to include all bytes from the tail of the dma buffer.
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@ -182,13 +166,12 @@ impl<'a, W: Word> DmaRingBuffer<'a, W> {
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// We have now copied out the data from dma_buf
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// Make sure that the just read part was not overwritten during the copy
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self.ndtr = dma.ndtr();
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if self.end() > self.first || dma.tcif() {
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if self.end() > self.first || dma.get_complete_count() > 1 {
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// The writer has entered the data that we have just read since we read out `end` in the beginning and until now.
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return Err(OverrunError);
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}
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self.first = (self.first + len) % self.dma_buf.len();
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self.expect_next_read_to_wrap = true;
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Ok(len)
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} else {
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// The provided read buffer is large enough to include all bytes from the tail of the dma buffer,
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@ -201,14 +184,14 @@ impl<'a, W: Word> DmaRingBuffer<'a, W> {
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compiler_fence(Ordering::SeqCst);
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// We have now copied out the data from dma_buf
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// Make sure that the just read part was not overwritten during the copy
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// Reset complete counter and make sure that the just read part was not overwritten during the copy
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self.ndtr = dma.ndtr();
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if self.end() > self.first || dma.tcif() {
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let complete_count = dma.reset_complete_count();
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if self.end() > self.first || complete_count > 1 {
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return Err(OverrunError);
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}
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self.first = head;
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self.expect_next_read_to_wrap = false;
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Ok(tail + head)
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}
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}
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@ -243,14 +226,14 @@ mod tests {
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struct TestCtrl {
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next_ndtr: RefCell<Option<usize>>,
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tcif: bool,
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complete_count: usize,
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}
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impl TestCtrl {
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pub const fn new() -> Self {
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Self {
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next_ndtr: RefCell::new(None),
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tcif: false,
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complete_count: 0,
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}
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}
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@ -264,12 +247,14 @@ mod tests {
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self.next_ndtr.borrow_mut().unwrap()
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}
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fn tcif(&self) -> bool {
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self.tcif
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fn get_complete_count(&self) -> usize {
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self.complete_count
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}
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fn clear_tcif(&mut self) {
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self.tcif = false;
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fn reset_complete_count(&mut self) -> usize {
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let old = self.complete_count;
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self.complete_count = 0;
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old
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}
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}
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@ -320,7 +305,7 @@ mod tests {
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ringbuf.ndtr = 10;
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// The dma controller has written 4 + 6 bytes and has reloaded NDTR
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ctrl.tcif = true;
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ctrl.complete_count = 1;
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ctrl.set_next_ndtr(10);
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assert!(!ringbuf.is_empty());
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@ -346,14 +331,14 @@ mod tests {
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ringbuf.ndtr = 6;
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// The dma controller has written 6 + 2 bytes and has reloaded NDTR
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ctrl.tcif = true;
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ctrl.complete_count = 1;
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ctrl.set_next_ndtr(14);
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||||
|
||||
let mut buf = [0; 2];
|
||||
assert_eq!(2, ringbuf.read(&mut ctrl, &mut buf).unwrap());
|
||||
assert_eq!([2, 3], buf);
|
||||
|
||||
assert_eq!(true, ctrl.tcif); // The interrupt flag IS NOT cleared
|
||||
assert_eq!(1, ctrl.complete_count); // The interrupt flag IS NOT cleared
|
||||
}
|
||||
|
||||
#[test]
|
||||
@ -365,14 +350,14 @@ mod tests {
|
||||
ringbuf.ndtr = 10;
|
||||
|
||||
// The dma controller has written 6 + 2 bytes and has reloaded NDTR
|
||||
ctrl.tcif = true;
|
||||
ctrl.complete_count = 1;
|
||||
ctrl.set_next_ndtr(14);
|
||||
|
||||
let mut buf = [0; 10];
|
||||
assert_eq!(10, ringbuf.read(&mut ctrl, &mut buf).unwrap());
|
||||
assert_eq!([12, 13, 14, 15, 0, 1, 2, 3, 4, 5], buf);
|
||||
|
||||
assert_eq!(false, ctrl.tcif); // The interrupt flag IS cleared
|
||||
assert_eq!(0, ctrl.complete_count); // The interrupt flag IS cleared
|
||||
}
|
||||
|
||||
#[test]
|
||||
@ -387,12 +372,12 @@ mod tests {
|
||||
assert!(ringbuf.is_empty()); // The ring buffer thinks that it is empty
|
||||
|
||||
// The dma controller has written exactly 16 bytes
|
||||
ctrl.tcif = true;
|
||||
ctrl.complete_count = 1;
|
||||
|
||||
let mut buf = [0; 2];
|
||||
assert_eq!(Err(OverrunError), ringbuf.read(&mut ctrl, &mut buf));
|
||||
|
||||
assert_eq!(false, ctrl.tcif); // The interrupt flag IS cleared
|
||||
assert_eq!(1, ctrl.complete_count); // The complete counter is not reset
|
||||
}
|
||||
|
||||
#[test]
|
||||
@ -404,13 +389,13 @@ mod tests {
|
||||
ringbuf.ndtr = 6;
|
||||
|
||||
// The dma controller has written 6 + 3 bytes and has reloaded NDTR
|
||||
ctrl.tcif = true;
|
||||
ctrl.complete_count = 1;
|
||||
ctrl.set_next_ndtr(13);
|
||||
|
||||
let mut buf = [0; 2];
|
||||
assert_eq!(Err(OverrunError), ringbuf.read(&mut ctrl, &mut buf));
|
||||
|
||||
assert_eq!(false, ctrl.tcif); // The interrupt flag IS cleared
|
||||
assert_eq!(1, ctrl.complete_count); // The complete counter is not reset
|
||||
}
|
||||
|
||||
#[test]
|
||||
@ -422,12 +407,12 @@ mod tests {
|
||||
ringbuf.ndtr = 10;
|
||||
|
||||
// The dma controller has written 6 + 13 bytes and has reloaded NDTR
|
||||
ctrl.tcif = true;
|
||||
ctrl.complete_count = 1;
|
||||
ctrl.set_next_ndtr(3);
|
||||
|
||||
let mut buf = [0; 2];
|
||||
assert_eq!(Err(OverrunError), ringbuf.read(&mut ctrl, &mut buf));
|
||||
|
||||
assert_eq!(false, ctrl.tcif); // The interrupt flag IS cleared
|
||||
assert_eq!(1, ctrl.complete_count); // The complete counter is not reset
|
||||
}
|
||||
}
|
||||
|
@ -4,8 +4,9 @@ use core::task::Poll;
|
||||
|
||||
use embassy_hal_common::drop::OnDrop;
|
||||
use embassy_hal_common::PeripheralRef;
|
||||
use futures::future::{select, Either};
|
||||
|
||||
use super::{rdr, sr, BasicInstance, Error, UartRx};
|
||||
use super::{clear_interrupt_flags, rdr, sr, BasicInstance, Error, UartRx};
|
||||
use crate::dma::ringbuffer::OverrunError;
|
||||
use crate::dma::RingBuffer;
|
||||
|
||||
@ -98,7 +99,8 @@ impl<'d, T: BasicInstance, RxDma: super::RxDma<T>> RingBufferedUartRx<'d, T, RxD
|
||||
}
|
||||
|
||||
/// Read bytes that are readily available in the ring buffer.
|
||||
/// If no bytes are currently available in the buffer the call waits until data are received.
|
||||
/// If no bytes are currently available in the buffer the call waits until the some
|
||||
/// bytes are available (at least one byte and at most half the buffer size)
|
||||
///
|
||||
/// Background receive is started if `start()` has not been previously called.
|
||||
///
|
||||
@ -107,10 +109,9 @@ impl<'d, T: BasicInstance, RxDma: super::RxDma<T>> RingBufferedUartRx<'d, T, RxD
|
||||
pub async fn read(&mut self, buf: &mut [u8]) -> Result<usize, Error> {
|
||||
let r = T::regs();
|
||||
|
||||
// Start background receive if it was not already started
|
||||
// SAFETY: read only
|
||||
let is_started = unsafe { r.cr3().read().dmar() };
|
||||
|
||||
// Start background receive if it was not already started
|
||||
if !is_started {
|
||||
self.start()?;
|
||||
}
|
||||
@ -132,8 +133,7 @@ impl<'d, T: BasicInstance, RxDma: super::RxDma<T>> RingBufferedUartRx<'d, T, RxD
|
||||
}
|
||||
}
|
||||
|
||||
let ndtr = self.ring_buf.get_remaining_transfers();
|
||||
self.ring_buf.set_ndtr(ndtr);
|
||||
self.ring_buf.reload_position();
|
||||
match self.ring_buf.read(buf) {
|
||||
Ok(len) if len == 0 => {}
|
||||
Ok(len) => {
|
||||
@ -148,28 +148,32 @@ impl<'d, T: BasicInstance, RxDma: super::RxDma<T>> RingBufferedUartRx<'d, T, RxD
|
||||
}
|
||||
}
|
||||
|
||||
// Wait for any data since `ndtr`
|
||||
self.wait_for_data(ndtr).await?;
|
||||
loop {
|
||||
self.wait_for_data_or_idle().await?;
|
||||
|
||||
self.ring_buf.reload_position();
|
||||
if !self.ring_buf.is_empty() {
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
// ndtr is now different than the value provided to `wait_for_data()`
|
||||
// Re-sample ndtr now when it has changed.
|
||||
self.ring_buf.set_ndtr(self.ring_buf.get_remaining_transfers());
|
||||
let len = self.ring_buf.read(buf).map_err(|_err| Error::Overrun)?;
|
||||
assert!(len > 0);
|
||||
|
||||
Ok(len)
|
||||
}
|
||||
|
||||
/// Wait for uart data
|
||||
async fn wait_for_data(&mut self, old_ndtr: usize) -> Result<(), Error> {
|
||||
/// Wait for uart idle or dma half-full or full
|
||||
async fn wait_for_data_or_idle(&mut self) -> Result<(), Error> {
|
||||
let r = T::regs();
|
||||
|
||||
// make sure USART state is restored to neutral state when this future is dropped
|
||||
let _drop = OnDrop::new(move || {
|
||||
// make sure USART state is restored to neutral state
|
||||
let _on_drop = OnDrop::new(move || {
|
||||
// SAFETY: only clears Rx related flags
|
||||
unsafe {
|
||||
r.cr1().modify(|w| {
|
||||
// disable RXNE interrupt
|
||||
w.set_rxneie(false);
|
||||
// disable idle line interrupt
|
||||
w.set_idleie(false);
|
||||
});
|
||||
}
|
||||
});
|
||||
@ -177,79 +181,68 @@ impl<'d, T: BasicInstance, RxDma: super::RxDma<T>> RingBufferedUartRx<'d, T, RxD
|
||||
// SAFETY: only sets Rx related flags
|
||||
unsafe {
|
||||
r.cr1().modify(|w| {
|
||||
// enable RXNE interrupt
|
||||
w.set_rxneie(true);
|
||||
// enable idle line interrupt
|
||||
w.set_idleie(true);
|
||||
});
|
||||
}
|
||||
|
||||
// future which completes when RX "not empty" is detected,
|
||||
// i.e. when there is data in uart rx register
|
||||
let rxne = poll_fn(|cx| {
|
||||
let s = T::state();
|
||||
compiler_fence(Ordering::SeqCst);
|
||||
|
||||
// Register waker to be awaken when RXNE interrupt is received
|
||||
// Future which completes when there is dma is half full or full
|
||||
let dma = poll_fn(|cx| {
|
||||
self.ring_buf.set_waker(cx.waker());
|
||||
|
||||
compiler_fence(Ordering::SeqCst);
|
||||
|
||||
self.ring_buf.reload_position();
|
||||
if !self.ring_buf.is_empty() {
|
||||
// Some data is now available
|
||||
Poll::Ready(())
|
||||
} else {
|
||||
Poll::Pending
|
||||
}
|
||||
});
|
||||
|
||||
// Future which completes when idle line is detected
|
||||
let uart = poll_fn(|cx| {
|
||||
let s = T::state();
|
||||
s.rx_waker.register(cx.waker());
|
||||
|
||||
compiler_fence(Ordering::SeqCst);
|
||||
|
||||
// SAFETY: read only and we only use Rx related flags
|
||||
let s = unsafe { sr(r).read() };
|
||||
let has_errors = s.pe() || s.fe() || s.ne() || s.ore();
|
||||
let sr = unsafe { sr(r).read() };
|
||||
|
||||
let has_errors = sr.pe() || sr.fe() || sr.ne() || sr.ore();
|
||||
if has_errors {
|
||||
if s.pe() {
|
||||
if sr.pe() {
|
||||
return Poll::Ready(Err(Error::Parity));
|
||||
} else if s.fe() {
|
||||
} else if sr.fe() {
|
||||
return Poll::Ready(Err(Error::Framing));
|
||||
} else if s.ne() {
|
||||
} else if sr.ne() {
|
||||
return Poll::Ready(Err(Error::Noise));
|
||||
} else {
|
||||
return Poll::Ready(Err(Error::Overrun));
|
||||
}
|
||||
}
|
||||
|
||||
// Re-sample ndtr and determine if it has changed since we started
|
||||
// waiting for data.
|
||||
let new_ndtr = self.ring_buf.get_remaining_transfers();
|
||||
if new_ndtr != old_ndtr {
|
||||
// Some data was received as NDTR has changed
|
||||
Poll::Ready(Ok(()))
|
||||
} else {
|
||||
// It may be that the DMA controller is currently busy consuming the
|
||||
// RX data register. We therefore wait register to become empty.
|
||||
while unsafe { sr(r).read().rxne() } {}
|
||||
|
||||
compiler_fence(Ordering::SeqCst);
|
||||
|
||||
// Re-get again: This time we know that the DMA controller has consumed
|
||||
// the current read register if it was busy doing so
|
||||
let new_ndtr = self.ring_buf.get_remaining_transfers();
|
||||
if new_ndtr != old_ndtr {
|
||||
// Some data was received as NDTR has changed
|
||||
if sr.idle() {
|
||||
// Idle line is detected
|
||||
Poll::Ready(Ok(()))
|
||||
} else {
|
||||
Poll::Pending
|
||||
}
|
||||
}
|
||||
});
|
||||
|
||||
compiler_fence(Ordering::SeqCst);
|
||||
|
||||
let new_ndtr = self.ring_buf.get_remaining_transfers();
|
||||
if new_ndtr != old_ndtr {
|
||||
// Fast path - NDTR has already changed, no reason to poll
|
||||
Ok(())
|
||||
} else {
|
||||
// NDTR has not changed since we first read from the ring buffer
|
||||
// Wait for RXNE interrupt...
|
||||
match rxne.await {
|
||||
Ok(()) => Ok(()),
|
||||
Err(e) => {
|
||||
match select(dma, uart).await {
|
||||
Either::Left(((), _)) => Ok(()),
|
||||
Either::Right((Ok(()), _)) => Ok(()),
|
||||
Either::Right((Err(e), _)) => {
|
||||
self.teardown_uart();
|
||||
Err(e)
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<T: BasicInstance, RxDma: super::RxDma<T>> Drop for RingBufferedUartRx<'_, T, RxDma> {
|
||||
|
@ -56,6 +56,7 @@ mod board {
|
||||
}
|
||||
|
||||
const ONE_BYTE_DURATION_US: u32 = 9_000_000 / 115200;
|
||||
const DMA_BUF_SIZE: usize = 64;
|
||||
|
||||
#[embassy_executor::main]
|
||||
async fn main(spawner: Spawner) {
|
||||
@ -114,7 +115,7 @@ async fn main(spawner: Spawner) {
|
||||
|
||||
let usart = Uart::new(usart, rx, tx, irq, tx_dma, rx_dma, config);
|
||||
let (tx, rx) = usart.split();
|
||||
static mut DMA_BUF: [u8; 64] = [0; 64];
|
||||
static mut DMA_BUF: [u8; DMA_BUF_SIZE] = [0; DMA_BUF_SIZE];
|
||||
let dma_buf = unsafe { DMA_BUF.as_mut() };
|
||||
let rx = rx.into_ring_buffered(dma_buf);
|
||||
|
||||
@ -159,7 +160,14 @@ async fn receive_task(mut rx: RingBufferedUartRx<'static, board::Uart, board::Rx
|
||||
loop {
|
||||
let mut buf = [0; 100];
|
||||
let max_len = 1 + (rng.next_u32() as usize % (buf.len() - 1));
|
||||
let received = rx.read(&mut buf[..max_len]).await.unwrap();
|
||||
let received = match rx.read(&mut buf[..max_len]).await {
|
||||
Ok(r) => r,
|
||||
Err(e) => {
|
||||
error!("Test fail! read error: {:?}", e);
|
||||
cortex_m::asm::bkpt();
|
||||
return;
|
||||
}
|
||||
};
|
||||
|
||||
if expected.is_none() {
|
||||
info!("Test started");
|
||||
@ -176,8 +184,11 @@ async fn receive_task(mut rx: RingBufferedUartRx<'static, board::Uart, board::Rx
|
||||
}
|
||||
|
||||
if received < max_len {
|
||||
let byte_count = rng.next_u32() % 64;
|
||||
Timer::after(Duration::from_micros((byte_count * ONE_BYTE_DURATION_US) as _)).await;
|
||||
let byte_count = rng.next_u32() % (DMA_BUF_SIZE as u32);
|
||||
let random_delay_us = (byte_count * ONE_BYTE_DURATION_US) as u64;
|
||||
if random_delay_us > 200 {
|
||||
Timer::after(Duration::from_micros(random_delay_us - 200)).await;
|
||||
}
|
||||
}
|
||||
|
||||
i += 1;
|
||||
|
@ -1,18 +1,19 @@
|
||||
use std::path::Path;
|
||||
use std::time::Duration;
|
||||
use std::{env, io, thread};
|
||||
use std::{env, io, process, thread};
|
||||
|
||||
use rand::random;
|
||||
use serial::SerialPort;
|
||||
|
||||
pub fn main() {
|
||||
if let Some(port_name) = env::args().nth(1) {
|
||||
let sleep = env::args().position(|x| x == "--sleep").is_some();
|
||||
let idles = env::args().position(|x| x == "--idles").is_some();
|
||||
|
||||
println!("Saturating port {:?} with 115200 8N1", port_name);
|
||||
println!("Sleep: {}", sleep);
|
||||
println!("Idles: {}", idles);
|
||||
println!("Process ID: {}", process::id());
|
||||
let mut port = serial::open(&port_name).unwrap();
|
||||
if saturate(&mut port, sleep).is_err() {
|
||||
if saturate(&mut port, idles).is_err() {
|
||||
eprintln!("Unable to saturate port");
|
||||
}
|
||||
} else {
|
||||
@ -23,7 +24,7 @@ pub fn main() {
|
||||
}
|
||||
}
|
||||
|
||||
fn saturate<T: SerialPort>(port: &mut T, sleep: bool) -> io::Result<()> {
|
||||
fn saturate<T: SerialPort>(port: &mut T, idles: bool) -> io::Result<()> {
|
||||
port.reconfigure(&|settings| {
|
||||
settings.set_baud_rate(serial::Baud115200)?;
|
||||
settings.set_char_size(serial::Bits8);
|
||||
@ -39,7 +40,7 @@ fn saturate<T: SerialPort>(port: &mut T, sleep: bool) -> io::Result<()> {
|
||||
|
||||
port.write_all(&buf)?;
|
||||
|
||||
if sleep {
|
||||
if idles {
|
||||
let micros = (random::<usize>() % 1000) as u64;
|
||||
println!("Sleeping {}us", micros);
|
||||
port.flush().unwrap();
|
||||
|
Loading…
Reference in New Issue
Block a user