Add TimerWakeupSource for the esp32-c6 deepsleep. (#1201)

CHANGELOG.md

@@ -26,6 +26,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - A way to push into I2S DMA buffer via a closure (#1189)
 - Added basic `LP-I2C` driver for C6 (#1185)
 - Ensuring that the random number generator is TRNG. (#1200)
+- ESP32-C6: Add timer wakeup source for deepsleep (#1201)
 
 ### Fixed
 

esp-hal/src/reset.rs

@@ -73,8 +73,12 @@ bitflags::bitflags! {
         const ExtEvent1Trig   = 1 << 1;
         /// GPIO wakeup (light sleep only)
         const GpioTrigEn      = 1 << 2;
+        #[cfg(not(any(esp32c6, esp32h2)))]
         /// Timer wakeup
         const TimerTrigEn     = 1 << 3;
+        #[cfg(any(esp32c6, esp32h2))]
+        /// Timer wakeup
+        const TimerTrigEn     = 1 << 4;
         #[cfg(pm_support_wifi_wakeup)]
         /// MAC wakeup (light sleep only)
         const WifiTrigEn      = 1 << 5;

esp-hal/src/rtc_cntl/sleep/esp32c6.rs

@@ -1,6 +1,7 @@
 use core::ops::Not;
 
 use crate::{
+    clock::Clock,
     efuse::Efuse,
     gpio::{Pins, RtcFunction},
     peripherals::Peripherals,
@@ -15,12 +16,44 @@ use crate::{
             RtcCalSel,
             SavedClockConfig,
         },
-        sleep::{Ext1WakeupSource, WakeSource, WakeTriggers, WakeupLevel},
+        sleep::{Ext1WakeupSource, TimerWakeupSource, WakeSource, WakeTriggers, WakeupLevel},
         RtcClock,
     },
     Rtc,
 };
 
+impl WakeSource for TimerWakeupSource {
+    fn apply(&self, rtc: &Rtc, triggers: &mut WakeTriggers, _sleep_config: &mut RtcSleepConfig) {
+        triggers.set_timer(true);
+
+        let lp_timer = unsafe { &*esp32c6::LP_TIMER::ptr() };
+        let clock_freq = RtcClock::get_slow_freq();
+        // TODO: maybe add sleep time adjustlemnt like idf
+        // TODO: maybe add check to prevent overflow?
+        let clock_hz = clock_freq.frequency().to_Hz() as u64;
+        let ticks = self.duration.as_micros() as u64 * clock_hz / 1_000_000u64;
+        // "alarm" time in slow rtc ticks
+        let now = rtc.get_time_raw();
+        let time_in_ticks = now + ticks;
+        unsafe {
+            lp_timer.tar0_high().write(|w| {
+                w.main_timer_tar_high0()
+                    .bits(((time_in_ticks >> 32) & 0xffff) as u16)
+            });
+            lp_timer.tar0_low().write(|w| {
+                w.main_timer_tar_low0()
+                    .bits((time_in_ticks & 0xffffffff) as u32)
+            });
+            lp_timer
+                .int_clr()
+                .write(|w| w.soc_wakeup_int_clr().set_bit());
+            lp_timer
+                .tar0_high()
+                .modify(|_, w| w.main_timer_tar_en0().set_bit());
+        }
+    }
+}
+
 impl Ext1WakeupSource<'_, '_> {
     /// Returns the currently configured wakeup pins.
     fn wakeup_pins() -> u8 {

esp-hal/src/rtc_cntl/sleep/mod.rs

@@ -21,7 +21,7 @@
 //!    * `BT (Bluetooth) wake` - light sleep only
 
 use core::cell::RefCell;
-#[cfg(any(esp32, esp32c3, esp32s3))]
+#[cfg(any(esp32, esp32c3, esp32s3, esp32c6))]
 use core::time::Duration;
 
 #[cfg(any(esp32, esp32s3))]
@@ -46,12 +46,12 @@ pub enum WakeupLevel {
 }
 
 #[derive(Debug, Default, Clone, Copy)]
-#[cfg(any(esp32, esp32c3, esp32s3))]
+#[cfg(any(esp32, esp32c3, esp32s3, esp32c6))]
 pub struct TimerWakeupSource {
     duration: Duration,
 }
 
-#[cfg(any(esp32, esp32c3, esp32s3))]
+#[cfg(any(esp32, esp32c3, esp32s3, esp32c6))]
 impl TimerWakeupSource {
     pub fn new(duration: Duration) -> Self {
         Self { duration }

examples/src/bin/sleep_timer.rs

@@ -1,6 +1,6 @@
 //! Demonstrates deep sleep with timer wakeup
 
-//% CHIPS: esp32 esp32c3 esp32s3
+//% CHIPS: esp32 esp32c3 esp32c6 esp32s3
 
 #![no_std]
 #![no_main]

examples/src/bin/sleep_timer_lpio.rs

@@ -1,10 +1,12 @@
-//! Demonstrates deep sleep with gpio2 (low) and gpio3 (high) as wakeup sources.
+//! Demonstrates deep sleep with timer, using gpio2 (low) and gpio3 (high) as wakeup sources.
 
 //% CHIPS: esp32c6
 
 #![no_std]
 #![no_main]
 
+use core::time::Duration;
+
 use esp_backtrace as _;
 use esp_hal::{
     clock::ClockControl,
@@ -15,7 +17,7 @@ use esp_hal::{
     rtc_cntl::{
         get_reset_reason,
         get_wakeup_cause,
-        sleep::{Ext1WakeupSource, WakeupLevel},
+        sleep::{Ext1WakeupSource, TimerWakeupSource, WakeupLevel},
         SocResetReason,
     },
     Cpu,
@@ -44,6 +46,8 @@ fn main() -> ! {
     println!("wake reason: {:?}", wake_reason);
 
     let mut delay = Delay::new(&clocks);
+    let timer = TimerWakeupSource::new(Duration::from_secs(10));
+
     let wakeup_pins: &mut [(&mut dyn RTCPinWithResistors, WakeupLevel)] = &mut [
         (&mut pin2, WakeupLevel::Low),
         (&mut pin3, WakeupLevel::High),
@@ -52,5 +56,5 @@ fn main() -> ! {
     let rtcio = Ext1WakeupSource::new(wakeup_pins);
     println!("sleeping!");
     delay.delay_ms(100u32);
-    rtc.sleep_deep(&[&rtcio], &mut delay);
+    rtc.sleep_deep(&[&timer, &rtcio], &mut delay);
 }