nrf: add WDT driver

This commit is contained in:
Dario Nieuwenhuis 2021-08-07 14:26:28 +02:00
parent e1abba69b7
commit 2540a960e5
10 changed files with 221 additions and 0 deletions

View File

@ -8,6 +8,9 @@ embassy_hal_common::peripherals! {
RTC0,
RTC1,
// WDT
WDT,
// RNG
RNG,

View File

@ -8,6 +8,9 @@ embassy_hal_common::peripherals! {
RTC0,
RTC1,
// WDT
WDT,
// RNG
RNG,

View File

@ -8,6 +8,9 @@ embassy_hal_common::peripherals! {
RTC0,
RTC1,
// WDT
WDT,
// RNG
RNG,

View File

@ -8,6 +8,9 @@ embassy_hal_common::peripherals! {
RTC0,
RTC1,
// WDT
WDT,
// RNG
RNG,

View File

@ -9,6 +9,9 @@ embassy_hal_common::peripherals! {
RTC1,
RTC2,
// WDT
WDT,
// RNG
RNG,

View File

@ -9,6 +9,9 @@ embassy_hal_common::peripherals! {
RTC1,
RTC2,
// WDT
WDT,
// RNG
RNG,

View File

@ -9,6 +9,9 @@ embassy_hal_common::peripherals! {
RTC1,
RTC2,
// WDT
WDT,
// RNG
RNG,

View File

@ -40,6 +40,7 @@ pub mod spim;
pub mod timer;
pub mod twim;
pub mod uarte;
pub mod wdt;
// This mod MUST go last, so that it sees all the `impl_foo!` macros
#[cfg(feature = "nrf52805")]

153
embassy-nrf/src/wdt.rs Normal file
View File

@ -0,0 +1,153 @@
//! HAL interface to the WDT peripheral.
//!
//! This HAL implements a basic watchdog timer with 1..=8 handles.
//! Once the watchdog has been started, it cannot be stopped.
use crate::pac::WDT;
use crate::peripherals;
const MIN_TICKS: u32 = 15;
#[non_exhaustive]
pub struct Config {
/// Number of 32768 Hz ticks in each watchdog period.
///
/// Note: there is a minimum of 15 ticks (458 microseconds). If a lower
/// number is provided, 15 ticks will be used as the configured value.
pub timeout_ticks: u32,
/// Should the watchdog continue to count during sleep modes?
pub run_during_sleep: bool,
/// Should the watchdog continue to count when the CPU is halted for debug?
pub run_during_debug_halt: bool,
}
impl Default for Config {
fn default() -> Self {
Self {
timeout_ticks: 32768, // 1 second
run_during_debug_halt: true,
run_during_sleep: true,
}
}
}
/// An interface to the Watchdog.
pub struct Watchdog {
_private: (),
}
impl Watchdog {
/// Try to create a new watchdog instance from the peripheral.
///
/// This function will return an error if the watchdog is already active
/// with a `config` different to the requested one, or a different number of
/// enabled handles.
///
/// `N` must be between 1 and 8, inclusive.
#[inline]
pub fn try_new<const N: usize>(
wdt: peripherals::WDT,
config: Config,
) -> Result<(Self, [WatchdogHandle; N]), peripherals::WDT> {
assert!(N >= 1 && N <= 8);
let r = unsafe { &*WDT::ptr() };
let crv = config.timeout_ticks.max(MIN_TICKS);
let rren = (1u32 << N) - 1;
if r.runstatus.read().runstatus().bit() {
let curr_config = r.config.read();
if curr_config.halt().bit() != config.run_during_debug_halt
|| curr_config.sleep().bit() != config.run_during_sleep
|| r.crv.read().bits() != crv
|| r.rren.read().bits() != rren
{
return Err(wdt);
}
} else {
r.config.write(|w| {
w.sleep().bit(config.run_during_sleep);
w.halt().bit(config.run_during_debug_halt);
w
});
r.intenset.write(|w| w.timeout().set_bit());
r.crv.write(|w| unsafe { w.bits(crv) });
r.rren.write(|w| unsafe { w.bits(rren) });
r.tasks_start.write(|w| unsafe { w.bits(1) });
}
let this = Self { _private: () };
const DUMMY_HANDLE: WatchdogHandle = WatchdogHandle { index: 0 };
let mut handles = [DUMMY_HANDLE; N];
for i in 0..N {
handles[i] = WatchdogHandle { index: i as u8 };
handles[i].pet();
}
Ok((this, handles))
}
/// Enable the watchdog interrupt.
///
/// NOTE: Although the interrupt will occur, there is no way to prevent
/// the reset from occurring. From the time the event was fired, the
/// system will reset two LFCLK ticks later (61 microseconds) if the
/// interrupt has been enabled.
#[inline(always)]
pub fn enable_interrupt(&mut self) {
let r = unsafe { &*WDT::ptr() };
r.intenset.write(|w| w.timeout().set_bit());
}
/// Disable the watchdog interrupt.
///
/// NOTE: This has no effect on the reset caused by the Watchdog.
#[inline(always)]
pub fn disable_interrupt(&mut self) {
let r = unsafe { &*WDT::ptr() };
r.intenclr.write(|w| w.timeout().set_bit());
}
/// Is the watchdog still awaiting pets from any handle?
///
/// This reports whether sufficient pets have been received from all
/// handles to prevent a reset this time period.
#[inline(always)]
pub fn awaiting_pets(&self) -> bool {
let r = unsafe { &*WDT::ptr() };
let enabled = r.rren.read().bits();
let status = r.reqstatus.read().bits();
(status & enabled) == 0
}
}
pub struct WatchdogHandle {
index: u8,
}
impl WatchdogHandle {
/// Pet the watchdog.
///
/// This function pets the given watchdog handle.
///
/// NOTE: All active handles must be pet within the time interval to
/// prevent a reset from occurring.
#[inline]
pub fn pet(&mut self) {
let r = unsafe { &*WDT::ptr() };
r.rr[self.index as usize].write(|w| w.rr().reload());
}
/// Has this handle been pet within the current window?
pub fn is_pet(&self) -> bool {
let r = unsafe { &*WDT::ptr() };
let rd = r.reqstatus.read().bits();
let idx = self.index as usize;
((rd >> idx) & 0x1) == 0
}
}

View File

@ -0,0 +1,46 @@
#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]
#![allow(incomplete_features)]
#[path = "../example_common.rs"]
mod example_common;
use defmt::*;
use embassy::executor::Spawner;
use embassy_nrf::gpio::{Input, Pull};
use embassy_nrf::gpiote::PortInput;
use embassy_nrf::wdt::{Config, Watchdog};
use embassy_nrf::Peripherals;
use embassy_traits::gpio::{WaitForHigh, WaitForLow};
#[embassy::main]
async fn main(_spawner: Spawner, p: Peripherals) {
info!("Hello World!");
let mut config = Config::default();
config.timeout_ticks = 32768 * 3; // 3 seconds
// This is needed for `probe-run` to be able to catch the panic message
// in the WDT interrupt. The core resets 2 ticks after firing the interrupt.
config.run_during_debug_halt = false;
let (_wdt, [mut handle]) = match Watchdog::try_new::<1>(p.WDT, config) {
Ok(x) => x,
Err(_) => {
info!("Watchdog already active with wrong config, waiting for it to timeout...");
loop {}
}
};
let mut button = PortInput::new(Input::new(p.P0_11, Pull::Up));
info!("Watchdog started, press button 1 to pet it or I'll reset in 3 seconds!");
loop {
button.wait_for_high().await;
button.wait_for_low().await;
info!("Button pressed, petting watchdog!");
handle.pet();
}
}