From e2e024a66fb0489a4f881e7dcad0e04a6122f750 Mon Sep 17 00:00:00 2001
From: Stephen D <webmaster@scd31.com>
Date: Fri, 2 Jun 2023 21:01:39 -0300
Subject: [PATCH] DMA wip. not working
---
src/main.rs | 222 +++++++++++++++++++++++++++++++++++++++-------------
1 file changed, 167 insertions(+), 55 deletions(-)
diff --git a/src/main.rs b/src/main.rs
index e6a2cc9..4087f6a 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -11,21 +11,34 @@ mod packet;
#[rtic::app(device = stm32f4xx_hal::pac, peripherals = true)]
mod app {
- use hal::block;
- use hal::gpio;
- use hal::pac::{SPI1, TIM5, USART1};
- use hal::prelude::*;
- use hal::serial::{Config, Event, Serial};
- use hal::spi::{Mode, Phase, Polarity, Spi};
- use hal::timer::Delay;
- use rf4463::config::RADIO_CONFIG_500_2;
- use rf4463::Rf4463;
+ use hal::{
+ block,
+ dma::{
+ config::DmaConfig,
+ traits::{Stream, StreamISR},
+ PeripheralToMemory, Stream2, StreamsTuple, Transfer,
+ },
+ gpio,
+ pac::{DMA2, SPI1, TIM5, USART1},
+ prelude::*,
+ serial::{self, Config, Rx, Serial, Tx},
+ spi::{Mode, Phase, Polarity, Spi},
+ timer::Delay,
+ };
+ use rf4463::{config::RADIO_CONFIG_500_2, Rf4463};
use ringbuffer::{ConstGenericRingBuffer, RingBuffer, RingBufferRead, RingBufferWrite};
+ use rtic::Mutex;
use crate::packet::Packet;
// in # packets
const BUFFER_LEN: usize = 50;
+ // # bytes
+ // if we make this too big, the interrupt may take too long to process them all
+ // and we could drop packets!
+ // ideally we would use the rf4463 interrupt (higher priority)
+ // to keep the transceiver fed
+ const DMA_BUFFER_LEN: usize = 128;
const MODE: Mode = Mode {
polarity: Polarity::IdleLow,
@@ -39,6 +52,14 @@ mod app {
Delay<TIM5, 1000000>,
>;
+ type RxTransfer = Transfer<
+ Stream2<DMA2>,
+ 4,
+ Rx<USART1>,
+ PeripheralToMemory,
+ &'static mut [u8; DMA_BUFFER_LEN],
+ >;
+
#[derive(Debug)]
enum SlaveCmd {
BufferStatus,
@@ -67,13 +88,24 @@ mod app {
struct Shared {
radio_temp: f32,
tx_buf: ConstGenericRingBuffer<Packet, BUFFER_LEN>,
+
+ // Can use lock free for any resources that are only shared between tasks of the same priority
+ #[lock_free]
+ state: SlaveState,
+
+ #[lock_free]
+ tx: Tx<USART1>,
+
+ #[lock_free]
+ rx_transfer: RxTransfer,
+
+ #[lock_free]
+ rx_buffer: Option<&'static mut [u8; DMA_BUFFER_LEN]>,
}
#[local]
struct Local {
radio: Radio,
- usart: Serial<USART1>,
- state: SlaveState,
}
#[init]
@@ -110,26 +142,53 @@ mod app {
let tx = gpioa.pa9;
let rx = gpioa.pa10;
- let mut usart = Serial::new(
+ let usart = Serial::new(
ctx.device.USART1,
(tx, rx),
- Config::default().baudrate(921_600.bps()),
+ Config::default()
+ .baudrate(921_600.bps())
+ .dma(serial::config::DmaConfig::Rx),
&clocks,
)
.unwrap();
- usart.listen(Event::Rxne);
+ let (tx, mut rx) = usart.split();
+
+ rx.listen_idle();
+
+ let dma2 = StreamsTuple::new(ctx.device.DMA2);
+
+ let rx_buffer1 =
+ cortex_m::singleton!(: [u8; DMA_BUFFER_LEN] = [0; DMA_BUFFER_LEN]).unwrap();
+ let rx_buffer2 =
+ cortex_m::singleton!(: [u8; DMA_BUFFER_LEN] = [0; DMA_BUFFER_LEN]).unwrap();
+
+ // todo figure out double buffering
+ let mut rx_transfer = Transfer::init_peripheral_to_memory(
+ dma2.2,
+ rx,
+ rx_buffer1,
+ None,
+ DmaConfig::default()
+ .memory_increment(true)
+ .fifo_enable(true)
+ .fifo_error_interrupt(true)
+ .transfer_complete_interrupt(true),
+ );
+
+ rx_transfer.start(|_rx| {});
(
Shared {
radio_temp: 0.0,
tx_buf: ConstGenericRingBuffer::new(),
- },
- Local {
- radio,
- usart,
+ tx,
state: SlaveState::Idle,
+
+ rx_transfer,
+ rx_buffer: Some(rx_buffer2),
},
+ Local { radio },
init::Monotonics(),
)
}
@@ -144,7 +203,7 @@ mod app {
i += 1;
- // get temp every 500 packets, or whenever when idle TODO
+ // get temp every 500 packets, or whenever when idle
if i >= 500 {
i = 0;
@@ -155,52 +214,105 @@ mod app {
}
}
- #[task(binds = USART1, priority=1, local = [state, usart], shared = [tx_buf, radio_temp])]
+ #[task(binds = USART1, priority=1, shared = [state, tx_buf, tx,radio_temp, rx_transfer, rx_buffer])]
fn usart1(mut ctx: usart1::Context) {
- let state = ctx.local.state;
- let usart = ctx.local.usart;
- let mut buf = ctx.shared.tx_buf;
-
- let x = block!(usart.read()).unwrap();
-
- match state {
- SlaveState::Idle => {
- if let Some(cmd) = SlaveCmd::from_u8(x) {
- match cmd {
- SlaveCmd::BufferStatus => {
- if buf.lock(|b| b.is_full()) {
- block!(usart.write(0x01)).unwrap(); // not enough space for a new packet
- } else {
- block!(usart.write(0x02)).unwrap(); // safe to send a packet
- }
- }
+ let transfer = &mut ctx.shared.rx_transfer;
+
+ if transfer.is_idle() {
+ let byte_count =
+ DMA_BUFFER_LEN - usize::from(Stream2::<DMA2>::get_number_of_transfers());
+ let new_buf = ctx.shared.rx_buffer.take().unwrap();
+ let (buffer, _) = transfer.next_transfer(new_buf).unwrap();
+ let bytes = &buffer[..byte_count];
+
+ handle_bytes(
+ ctx.shared.state,
+ ctx.shared.tx_buf,
+ ctx.shared.tx,
+ ctx.shared.radio_temp,
+ bytes,
+ );
+
+ *ctx.shared.rx_buffer = Some(buffer);
+ }
+ }
+
+ // Must be same priority as USART1
+ #[task(binds = DMA2_STREAM2, priority=1, shared = [state, tx_buf, tx, radio_temp, rx_transfer, rx_buffer])]
+ fn dma2_stream2(mut ctx: dma2_stream2::Context) {
+ let transfer = &mut ctx.shared.rx_transfer;
+
+ if Stream2::<DMA2>::get_fifo_error_flag() {
+ transfer.clear_fifo_error_interrupt();
+ }
+ if Stream2::<DMA2>::get_transfer_complete_flag() {
+ transfer.clear_transfer_complete_interrupt();
+
+ let new_buf = ctx.shared.rx_buffer.take().unwrap();
+ let (buffer, _) = transfer.next_transfer(new_buf).unwrap();
+
+ handle_bytes(
+ ctx.shared.state,
+ ctx.shared.tx_buf,
+ ctx.shared.tx,
+ ctx.shared.radio_temp,
+ buffer,
+ );
+
+ *ctx.shared.rx_buffer = Some(buffer);
+ }
+ }
- SlaveCmd::SendPacket => {
- if buf.lock(|b| b.len() >= b.capacity() - 1) {
- block!(usart.write(0x01)).unwrap(); // not enough space for a new packet
- } else {
- block!(usart.write(0x02)).unwrap(); // safe to send a packet
+ fn handle_bytes<
+ B: Mutex<T = ConstGenericRingBuffer<Packet, BUFFER_LEN>>,
+ RT: Mutex<T = f32>,
+ >(
+ state: &mut SlaveState,
+ mut buf: B,
+ tx: &mut Tx<USART1>,
+ mut radio_temp: RT,
+ bytes: &[u8],
+ ) {
+ for &x in bytes {
+ match state {
+ SlaveState::Idle => {
+ if let Some(cmd) = SlaveCmd::from_u8(x) {
+ match cmd {
+ SlaveCmd::BufferStatus => {
+ if buf.lock(|b| b.is_full()) {
+ block!(tx.write(0x01)).unwrap(); // not enough space for a new packet
+ } else {
+ block!(tx.write(0x02)).unwrap(); // safe to send a packet
+ }
}
- *state = SlaveState::RecvPacket(Packet::default());
- }
+ SlaveCmd::SendPacket => {
+ if buf.lock(|b| b.len() >= b.capacity() - 1) {
+ block!(tx.write(0x01)).unwrap(); // not enough space for a new packet
+ } else {
+ block!(tx.write(0x02)).unwrap(); // safe to send a packet
+ }
- SlaveCmd::GetTemp => {
- let temp = ctx.shared.radio_temp.lock(|x| *x);
- usart.bwrite_all(&temp.to_le_bytes()).unwrap();
+ *state = SlaveState::RecvPacket(Packet::default());
+ }
+
+ SlaveCmd::GetTemp => {
+ let temp = radio_temp.lock(|x| *x);
+ tx.bwrite_all(&temp.to_le_bytes()).unwrap();
+ }
}
}
}
- }
- SlaveState::RecvPacket(pkt) => {
- pkt.push(x);
- if pkt.is_complete() {
- buf.lock(|b| b.enqueue(pkt.clone()));
+ SlaveState::RecvPacket(pkt) => {
+ pkt.push(x);
+ if pkt.is_complete() {
+ buf.lock(|b| b.enqueue(pkt.clone()));
- *state = SlaveState::Idle;
+ *state = SlaveState::Idle;
+ }
}
- }
- };
+ };
+ }
}
}
--
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