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stm32/dma: refactor.

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This commit is contained in:
Dario Nieuwenhuis
2023-04-17 00:04:54 +02:00
parent 46227bec1e
commit 173c65b543
14 changed files with 1025 additions and 1092 deletions
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580
embassy-stm32/src/dma/dma.rs
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@ -1,15 +1,44 @@
use core::future::Future;
use core::pin::Pin;
use core::sync::atomic::{fence, Ordering};
use core::task::Waker;
use core::task::{Context, Poll};
use embassy_cortex_m::interrupt::Priority;
use embassy_hal_common::{into_ref, Peripheral, PeripheralRef};
use embassy_sync::waitqueue::AtomicWaker;
use pac::dma::regs;
use super::{Burst, FifoThreshold, FlowControl, Request, TransferOptions, Word, WordSize};
use super::{Dir, Word, WordSize};
use crate::_generated::DMA_CHANNEL_COUNT;
use crate::interrupt::{Interrupt, InterruptExt};
use crate::pac::dma::{regs, vals};
use crate::pac::dma::vals;
use crate::{interrupt, pac};
#[derive(Debug, Copy, Clone, PartialEq, Eq)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
#[non_exhaustive]
pub struct TransferOptions {
/// Peripheral burst transfer configuration
pub pburst: Burst,
/// Memory burst transfer configuration
pub mburst: Burst,
/// Flow control configuration
pub flow_ctrl: FlowControl,
/// FIFO threshold for DMA FIFO mode. If none, direct mode is used.
pub fifo_threshold: Option<FifoThreshold>,
}
impl Default for TransferOptions {
fn default() -> Self {
Self {
pburst: Burst::Single,
mburst: Burst::Single,
flow_ctrl: FlowControl::Dma,
fifo_threshold: None,
}
}
}
impl From<WordSize> for vals::Size {
fn from(raw: WordSize) -> Self {
match raw {
@ -20,6 +49,28 @@ impl From<WordSize> for vals::Size {
}
}
impl From<Dir> for vals::Dir {
fn from(raw: Dir) -> Self {
match raw {
Dir::MemoryToPeripheral => Self::MEMORYTOPERIPHERAL,
Dir::PeripheralToMemory => Self::PERIPHERALTOMEMORY,
}
}
}
#[derive(Debug, Copy, Clone, PartialEq, Eq)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
pub enum Burst {
/// Single transfer
Single,
/// Incremental burst of 4 beats
Incr4,
/// Incremental burst of 8 beats
Incr8,
/// Incremental burst of 16 beats
Incr16,
}
impl From<Burst> for vals::Burst {
fn from(burst: Burst) -> Self {
match burst {
@ -31,6 +82,15 @@ impl From<Burst> for vals::Burst {
}
}
#[derive(Debug, Copy, Clone, PartialEq, Eq)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
pub enum FlowControl {
/// Flow control by DMA
Dma,
/// Flow control by peripheral
Peripheral,
}
impl From<FlowControl> for vals::Pfctrl {
fn from(flow: FlowControl) -> Self {
match flow {
@ -40,6 +100,19 @@ impl From<FlowControl> for vals::Pfctrl {
}
}
#[derive(Debug, Copy, Clone, PartialEq, Eq)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
pub enum FifoThreshold {
/// 1/4 full FIFO
Quarter,
/// 1/2 full FIFO
Half,
/// 3/4 full FIFO
ThreeQuarters,
/// Full FIFO
Full,
}
impl From<FifoThreshold> for vals::Fth {
fn from(value: FifoThreshold) -> Self {
match value {
@ -51,27 +124,15 @@ impl From<FifoThreshold> for vals::Fth {
}
}
struct ChannelState {
waker: AtomicWaker,
}
impl ChannelState {
const fn new() -> Self {
Self {
waker: AtomicWaker::new(),
}
}
}
struct State {
channels: [ChannelState; DMA_CHANNEL_COUNT],
ch_wakers: [AtomicWaker; DMA_CHANNEL_COUNT],
}
impl State {
const fn new() -> Self {
const CH: ChannelState = ChannelState::new();
const AW: AtomicWaker = AtomicWaker::new();
Self {
channels: [CH; DMA_CHANNEL_COUNT],
ch_wakers: [AW; DMA_CHANNEL_COUNT],
}
}
}
@ -92,158 +153,183 @@ pub(crate) unsafe fn init(irq_priority: Priority) {
foreach_dma_channel! {
($channel_peri:ident, $dma_peri:ident, dma, $channel_num:expr, $index:expr, $dmamux:tt) => {
impl crate::dma::sealed::Channel for crate::peripherals::$channel_peri {
unsafe fn start_write<W: Word>(&mut self, request: Request, buf: *const [W], reg_addr: *mut W, options: TransferOptions) {
let (ptr, len) = super::slice_ptr_parts(buf);
low_level_api::start_transfer(
pac::$dma_peri,
$channel_num,
request,
vals::Dir::MEMORYTOPERIPHERAL,
reg_addr as *const u32,
ptr as *mut u32,
len,
true,
vals::Size::from(W::bits()),
options,
#[cfg(dmamux)]
<Self as super::dmamux::sealed::MuxChannel>::DMAMUX_REGS,
#[cfg(dmamux)]
<Self as super::dmamux::sealed::MuxChannel>::DMAMUX_CH_NUM,
)
impl sealed::Channel for crate::peripherals::$channel_peri {
fn regs(&self) -> pac::dma::Dma {
pac::$dma_peri
}
unsafe fn start_write_repeated<W: Word>(&mut self, request: Request, repeated: *const W, count: usize, reg_addr: *mut W, options: TransferOptions) {
low_level_api::start_transfer(
pac::$dma_peri,
$channel_num,
request,
vals::Dir::MEMORYTOPERIPHERAL,
reg_addr as *const u32,
repeated as *mut u32,
count,
false,
vals::Size::from(W::bits()),
options,
#[cfg(dmamux)]
<Self as super::dmamux::sealed::MuxChannel>::DMAMUX_REGS,
#[cfg(dmamux)]
<Self as super::dmamux::sealed::MuxChannel>::DMAMUX_CH_NUM,
)
fn num(&self) -> usize {
$channel_num
}
unsafe fn start_read<W: Word>(&mut self, request: Request, reg_addr: *const W, buf: *mut [W], options: TransferOptions) {
let (ptr, len) = super::slice_ptr_parts_mut(buf);
low_level_api::start_transfer(
pac::$dma_peri,
$channel_num,
request,
vals::Dir::PERIPHERALTOMEMORY,
reg_addr as *const u32,
ptr as *mut u32,
len,
true,
vals::Size::from(W::bits()),
options,
#[cfg(dmamux)]
<Self as super::dmamux::sealed::MuxChannel>::DMAMUX_REGS,
#[cfg(dmamux)]
<Self as super::dmamux::sealed::MuxChannel>::DMAMUX_CH_NUM,
);
fn index(&self) -> usize {
$index
}
unsafe fn start_double_buffered_read<W: Word>(
&mut self,
request: Request,
reg_addr: *const W,
buffer0: *mut W,
buffer1: *mut W,
buffer_len: usize,
options: TransferOptions,
) {
low_level_api::start_dbm_transfer(
pac::$dma_peri,
$channel_num,
request,
vals::Dir::PERIPHERALTOMEMORY,
reg_addr as *const u32,
buffer0 as *mut u32,
buffer1 as *mut u32,
buffer_len,
true,
vals::Size::from(W::bits()),
options,
#[cfg(dmamux)]
<Self as super::dmamux::sealed::MuxChannel>::DMAMUX_REGS,
#[cfg(dmamux)]
<Self as super::dmamux::sealed::MuxChannel>::DMAMUX_CH_NUM,
);
}
unsafe fn set_buffer0<W: Word>(&mut self, buffer: *mut W) {
low_level_api::set_dbm_buffer0(pac::$dma_peri, $channel_num, buffer as *mut u32);
}
unsafe fn set_buffer1<W: Word>(&mut self, buffer: *mut W) {
low_level_api::set_dbm_buffer1(pac::$dma_peri, $channel_num, buffer as *mut u32);
}
unsafe fn is_buffer0_accessible(&mut self) -> bool {
low_level_api::is_buffer0_accessible(pac::$dma_peri, $channel_num)
}
fn request_stop(&mut self) {
unsafe {low_level_api::request_stop(pac::$dma_peri, $channel_num);}
}
fn is_running(&self) -> bool {
unsafe {low_level_api::is_running(pac::$dma_peri, $channel_num)}
}
fn remaining_transfers(&mut self) -> u16 {
unsafe {low_level_api::get_remaining_transfers(pac::$dma_peri, $channel_num)}
}
fn set_waker(&mut self, waker: &Waker) {
unsafe {low_level_api::set_waker($index, waker )}
}
fn on_irq() {
unsafe {
low_level_api::on_irq_inner(pac::$dma_peri, $channel_num, $index);
}
unsafe { on_irq_inner(pac::$dma_peri, $channel_num, $index) }
}
}
impl crate::dma::Channel for crate::peripherals::$channel_peri { }
impl Channel for crate::peripherals::$channel_peri {}
};
}
mod low_level_api {
/// Safety: Must be called with a matching set of parameters for a valid dma channel
pub(crate) unsafe fn on_irq_inner(dma: pac::dma::Dma, channel_num: usize, index: usize) {
let cr = dma.st(channel_num).cr();
let isr = dma.isr(channel_num / 4).read();
if isr.teif(channel_num % 4) {
panic!("DMA: error on DMA@{:08x} channel {}", dma.0 as u32, channel_num);
}
if isr.tcif(channel_num % 4) && cr.read().tcie() {
/* acknowledge transfer complete interrupt */
dma.ifcr(channel_num / 4).write(|w| w.set_tcif(channel_num % 4, true));
STATE.ch_wakers[index].wake();
}
}
#[cfg(any(dma_v2, dmamux))]
pub type Request = u8;
#[cfg(not(any(dma_v2, dmamux)))]
pub type Request = ();
#[cfg(dmamux)]
pub trait Channel: sealed::Channel + Peripheral<P = Self> + 'static + super::dmamux::MuxChannel {}
#[cfg(not(dmamux))]
pub trait Channel: sealed::Channel + Peripheral<P = Self> + 'static {}
pub(crate) mod sealed {
use super::*;
pub unsafe fn start_transfer(
dma: pac::dma::Dma,
channel_number: u8,
pub trait Channel {
fn regs(&self) -> pac::dma::Dma;
fn num(&self) -> usize;
fn index(&self) -> usize;
fn on_irq();
}
}
#[must_use = "futures do nothing unless you `.await` or poll them"]
pub struct Transfer<'a, C: Channel> {
channel: PeripheralRef<'a, C>,
}
impl<'a, C: Channel> Transfer<'a, C> {
pub unsafe fn new_read<W: Word>(
channel: impl Peripheral<P = C> + 'a,
request: Request,
dir: vals::Dir,
peri_addr: *mut W,
buf: &'a mut [W],
options: TransferOptions,
) -> Self {
Self::new_read_raw(channel, request, peri_addr, buf, options)
}
pub unsafe fn new_read_raw<W: Word>(
channel: impl Peripheral<P = C> + 'a,
request: Request,
peri_addr: *mut W,
buf: *mut [W],
options: TransferOptions,
) -> Self {
into_ref!(channel);
let (ptr, len) = super::slice_ptr_parts_mut(buf);
assert!(len > 0 && len <= 0xFFFF);
Self::new_inner(
channel,
request,
Dir::PeripheralToMemory,
peri_addr as *const u32,
ptr as *mut u32,
len,
true,
W::bits(),
options,
)
}
pub unsafe fn new_write<W: Word>(
channel: impl Peripheral<P = C> + 'a,
request: Request,
buf: &'a [W],
peri_addr: *mut W,
options: TransferOptions,
) -> Self {
Self::new_write_raw(channel, request, buf, peri_addr, options)
}
pub unsafe fn new_write_raw<W: Word>(
channel: impl Peripheral<P = C> + 'a,
request: Request,
buf: *const [W],
peri_addr: *mut W,
options: TransferOptions,
) -> Self {
into_ref!(channel);
let (ptr, len) = super::slice_ptr_parts(buf);
assert!(len > 0 && len <= 0xFFFF);
Self::new_inner(
channel,
request,
Dir::MemoryToPeripheral,
peri_addr as *const u32,
ptr as *mut u32,
len,
true,
W::bits(),
options,
)
}
pub unsafe fn new_write_repeated<W: Word>(
channel: impl Peripheral<P = C> + 'a,
request: Request,
repeated: &'a W,
count: usize,
peri_addr: *mut W,
options: TransferOptions,
) -> Self {
into_ref!(channel);
Self::new_inner(
channel,
request,
Dir::MemoryToPeripheral,
peri_addr as *const u32,
repeated as *const W as *mut u32,
count,
false,
W::bits(),
options,
)
}
unsafe fn new_inner(
channel: PeripheralRef<'a, C>,
_request: Request,
dir: Dir,
peri_addr: *const u32,
mem_addr: *mut u32,
mem_len: usize,
incr_mem: bool,
data_size: vals::Size,
data_size: WordSize,
options: TransferOptions,
#[cfg(dmamux)] dmamux_regs: pac::dmamux::Dmamux,
#[cfg(dmamux)] dmamux_ch_num: u8,
) {
#[cfg(dmamux)]
super::super::dmamux::configure_dmamux(dmamux_regs, dmamux_ch_num, request);
) -> Self {
let ch = channel.regs().st(channel.num());
// "Preceding reads and writes cannot be moved past subsequent writes."
fence(Ordering::SeqCst);
reset_status(dma, channel_number);
let mut this = Self { channel };
this.clear_irqs();
#[cfg(dmamux)]
super::dmamux::configure_dmamux(&mut *this.channel, _request);
let ch = dma.st(channel_number as _);
ch.par().write_value(peri_addr as u32);
ch.m0ar().write_value(mem_addr as u32);
ch.ndtr().write_value(regs::Ndtr(mem_len as _));
@ -258,15 +344,14 @@ mod low_level_api {
}
});
ch.cr().write(|w| {
w.set_dir(dir);
w.set_msize(data_size);
w.set_psize(data_size);
w.set_dir(dir.into());
w.set_msize(data_size.into());
w.set_psize(data_size.into());
w.set_pl(vals::Pl::VERYHIGH);
if incr_mem {
w.set_minc(vals::Inc::INCREMENTED);
} else {
w.set_minc(vals::Inc::FIXED);
}
w.set_minc(match incr_mem {
true => vals::Inc::INCREMENTED,
false => vals::Inc::FIXED,
});
w.set_pinc(vals::Inc::FIXED);
w.set_teie(true);
w.set_tcie(true);
@ -274,7 +359,7 @@ mod low_level_api {
w.set_trbuff(true);
#[cfg(dma_v2)]
w.set_chsel(request);
w.set_chsel(_request);
w.set_pburst(options.pburst.into());
w.set_mburst(options.mburst.into());
@ -282,159 +367,76 @@ mod low_level_api {
w.set_en(true);
});
this
}
pub unsafe fn start_dbm_transfer(
dma: pac::dma::Dma,
channel_number: u8,
request: Request,
dir: vals::Dir,
peri_addr: *const u32,
mem0_addr: *mut u32,
mem1_addr: *mut u32,
mem_len: usize,
incr_mem: bool,
data_size: vals::Size,
options: TransferOptions,
#[cfg(dmamux)] dmamux_regs: pac::dmamux::Dmamux,
#[cfg(dmamux)] dmamux_ch_num: u8,
) {
#[cfg(dmamux)]
super::super::dmamux::configure_dmamux(dmamux_regs, dmamux_ch_num, request);
fn clear_irqs(&mut self) {
let isrn = self.channel.num() / 4;
let isrbit = self.channel.num() % 4;
trace!(
"Starting DBM transfer with 0: 0x{:x}, 1: 0x{:x}, len: 0x{:x}",
mem0_addr as u32,
mem1_addr as u32,
mem_len
);
// "Preceding reads and writes cannot be moved past subsequent writes."
fence(Ordering::SeqCst);
reset_status(dma, channel_number);
let ch = dma.st(channel_number as _);
ch.par().write_value(peri_addr as u32);
ch.m0ar().write_value(mem0_addr as u32);
// configures the second buffer for DBM
ch.m1ar().write_value(mem1_addr as u32);
ch.ndtr().write_value(regs::Ndtr(mem_len as _));
ch.cr().write(|w| {
w.set_dir(dir);
w.set_msize(data_size);
w.set_psize(data_size);
w.set_pl(vals::Pl::VERYHIGH);
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);
#[cfg(dma_v1)]
w.set_trbuff(true);
#[cfg(dma_v2)]
w.set_chsel(request);
// enable double buffered mode
w.set_dbm(vals::Dbm::ENABLED);
w.set_pburst(options.pburst.into());
w.set_mburst(options.mburst.into());
w.set_pfctrl(options.flow_ctrl.into());
w.set_en(true);
});
unsafe {
self.channel.regs().ifcr(isrn).write(|w| {
w.set_tcif(isrbit, true);
w.set_teif(isrbit, true);
})
}
}
pub unsafe fn set_dbm_buffer0(dma: pac::dma::Dma, channel_number: u8, mem_addr: *mut u32) {
// get a handle on the channel itself
let ch = dma.st(channel_number as _);
// change M0AR to the new address
ch.m0ar().write_value(mem_addr as _);
}
pub unsafe fn set_dbm_buffer1(dma: pac::dma::Dma, channel_number: u8, mem_addr: *mut u32) {
// get a handle on the channel itself
let ch = dma.st(channel_number as _);
// change M1AR to the new address
ch.m1ar().write_value(mem_addr as _);
}
pub unsafe fn is_buffer0_accessible(dma: pac::dma::Dma, channel_number: u8) -> bool {
// get a handle on the channel itself
let ch = dma.st(channel_number as _);
// check the current target register value
ch.cr().read().ct() == vals::Ct::MEMORY1
}
/// Stops the DMA channel.
pub unsafe fn request_stop(dma: pac::dma::Dma, channel_number: u8) {
// get a handle on the channel itself
let ch = dma.st(channel_number as _);
pub fn request_stop(&mut self) {
let ch = self.channel.regs().st(self.channel.num());
// Disable the channel. Keep the IEs enabled so the irqs still fire.
ch.cr().write(|w| {
w.set_teie(true);
w.set_tcie(true);
});
// "Subsequent reads and writes cannot be moved ahead of preceding reads."
fence(Ordering::SeqCst);
unsafe {
ch.cr().write(|w| {
w.set_teie(true);
w.set_tcie(true);
})
}
}
/// Gets the running status of the channel
pub unsafe fn is_running(dma: pac::dma::Dma, ch: u8) -> bool {
// get a handle on the channel itself
let ch = dma.st(ch as _);
// Get whether it's enabled (running)
ch.cr().read().en()
pub fn is_running(&mut self) -> bool {
let ch = self.channel.regs().st(self.channel.num());
unsafe { ch.cr().read() }.en()
}
/// Gets the total remaining transfers for the channel
/// Note: this will be zero for transfers that completed without cancellation.
pub unsafe fn get_remaining_transfers(dma: pac::dma::Dma, ch: u8) -> u16 {
// get a handle on the channel itself
let ch = dma.st(ch as _);
// read the remaining transfer count. If this is zero, the transfer completed fully.
ch.ndtr().read().ndt()
pub fn get_remaining_transfers(&self) -> u16 {
let ch = self.channel.regs().st(self.channel.num());
unsafe { ch.ndtr().read() }.ndt()
}
/// Sets the waker for the specified DMA channel
pub unsafe fn set_waker(state_number: usize, waker: &Waker) {
STATE.channels[state_number].waker.register(waker);
pub fn blocking_wait(mut self) {
while self.is_running() {}
// "Subsequent reads and writes cannot be moved ahead of preceding reads."
fence(Ordering::SeqCst);
core::mem::forget(self);
}
}
pub unsafe fn reset_status(dma: pac::dma::Dma, channel_number: u8) {
let isrn = channel_number as usize / 4;
let isrbit = channel_number as usize % 4;
impl<'a, C: Channel> Drop for Transfer<'a, C> {
fn drop(&mut self) {
self.request_stop();
while self.is_running() {}
dma.ifcr(isrn).write(|w| {
w.set_tcif(isrbit, true);
w.set_teif(isrbit, true);
});
// "Subsequent reads and writes cannot be moved ahead of preceding reads."
fence(Ordering::SeqCst);
}
}
/// Safety: Must be called with a matching set of parameters for a valid dma channel
pub unsafe fn on_irq_inner(dma: pac::dma::Dma, channel_num: u8, state_index: u8) {
let channel_num = channel_num as usize;
let state_index = state_index as usize;
impl<'a, C: Channel> Unpin for Transfer<'a, C> {}
impl<'a, C: Channel> Future for Transfer<'a, C> {
type Output = ();
fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
STATE.ch_wakers[self.channel.index()].register(cx.waker());
let cr = dma.st(channel_num).cr();
let isr = dma.isr(channel_num / 4).read();
if isr.teif(channel_num % 4) {
panic!("DMA: error on DMA@{:08x} channel {}", dma.0 as u32, channel_num);
}
if isr.tcif(channel_num % 4) && cr.read().tcie() {
/* acknowledge transfer complete interrupt */
dma.ifcr(channel_num / 4).write(|w| w.set_tcif(channel_num % 4, true));
STATE.channels[state_index].waker.wake();
if self.is_running() {
Poll::Pending
} else {
Poll::Ready(())
}
}
}