Add SYSTIMER ETM

CHANGELOG.md

@@ -21,6 +21,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Implement `embeded_hal_async::delay::DelayUs` trait for `SYSTIMER` alarms (#812)
 - ETM driver, GPIO ETM (#819)
 - (G)DMA AES support (#821)
+- SYSTIMER ETM functionality (#828)
 
 ### Changed
 

esp-hal-common/src/systimer.rs

@@ -65,6 +65,10 @@ impl<'d> SystemTimer<'d> {
 
     pub fn new(p: impl Peripheral<P = SYSTIMER> + 'd) -> Self {
         crate::into_ref!(p);
+
+        #[cfg(soc_etm)]
+        etm::enable_etm();
+
         Self {
             _inner: p,
             alarm0: Alarm::new(),
@@ -365,3 +369,60 @@ mod asynch {
         WAKERS[2].wake();
     }
 }
+
+#[cfg(soc_etm)]
+pub mod etm {
+    //! # Event Task Matrix Function
+    //!
+    //! ## Overview
+    //!
+    //!    The system timer supports the Event Task Matrix (ETM) function, which
+    //! allows the system timer’s    ETM events to trigger any
+    //!    peripherals’ ETM tasks.
+    //!
+    //!    The system timer can generate the following ETM events:
+    //!    - SYSTIMER_EVT_CNT_CMPx: Indicates the alarm pulses generated by
+    //!      COMPx
+    //!
+    //! ## Example
+    //! ```no_run
+    //! let syst = SystemTimer::new(peripherals.SYSTIMER);
+    //! let mut alarm0 = syst.alarm0.into_periodic();
+    //! alarm0.set_period(1u32.secs());
+    //!
+    //! let timer_event = SysTimerEtmEvent::new(&mut alarm0);
+    //! ```
+
+    use super::*;
+
+    /// An ETM controlled SYSTIMER event
+    pub struct SysTimerEtmEvent<'a, M, const N: u8> {
+        alarm: &'a mut Alarm<M, N>,
+    }
+
+    impl<'a, M, const N: u8> SysTimerEtmEvent<'a, M, N> {
+        /// Creates an ETM event from the given [Alarm]
+        pub fn new(alarm: &'a mut Alarm<M, N>) -> Self {
+            Self { alarm }
+        }
+
+        /// Execute closure f with mutable access to the wrapped [Alarm].
+        pub fn with<R>(&self, f: impl FnOnce(&&'a mut Alarm<M, N>) -> R) -> R {
+            let alarm = &self.alarm;
+            f(alarm)
+        }
+    }
+
+    impl<'a, M, const N: u8> crate::etm::private::Sealed for SysTimerEtmEvent<'a, M, N> {}
+
+    impl<'a, M, const N: u8> crate::etm::EtmEvent for SysTimerEtmEvent<'a, M, N> {
+        fn id(&self) -> u8 {
+            50 + N
+        }
+    }
+
+    pub(super) fn enable_etm() {
+        let syst = unsafe { crate::peripherals::SYSTIMER::steal() };
+        syst.conf.modify(|_, w| w.etm_en().set_bit());
+    }
+}

esp32c6-hal/examples/etm_blinky_systimer.rs

@@ -0,0 +1,45 @@
+//! Control LED on GPIO 1 by the systimer via ETM
+
+#![no_std]
+#![no_main]
+
+use esp32c6_hal::{
+    clock::ClockControl,
+    etm::Etm,
+    gpio::{etm::GpioEtmChannels, IO},
+    peripherals::Peripherals,
+    prelude::*,
+    systimer::{etm::SysTimerEtmEvent, SystemTimer},
+};
+use esp_backtrace as _;
+
+#[entry]
+fn main() -> ! {
+    esp_println::logger::init_logger_from_env();
+    let peripherals = Peripherals::take();
+    let system = peripherals.PCR.split();
+    let _clocks = ClockControl::boot_defaults(system.clock_control).freeze();
+
+    let syst = SystemTimer::new(peripherals.SYSTIMER);
+    let mut alarm0 = syst.alarm0.into_periodic();
+    alarm0.set_period(1u32.secs());
+
+    let io = IO::new(peripherals.GPIO, peripherals.IO_MUX);
+    let mut led = io.pins.gpio1.into_push_pull_output();
+
+    // setup ETM
+    let gpio_ext = GpioEtmChannels::new(peripherals.GPIO_SD);
+    let led_task = gpio_ext.channel0_task.toggle(&mut led);
+
+    let timer_event = SysTimerEtmEvent::new(&mut alarm0);
+
+    let etm = Etm::new(peripherals.SOC_ETM);
+    let channel0 = etm.channel0;
+
+    // make sure the configured channel doesn't get dropped - dropping it will
+    // disable the channel
+    let _configured_channel = channel0.setup(&timer_event, &led_task);
+
+    // the LED is controlled by the timer without involving the CPU
+    loop {}
+}

esp32h2-hal/examples/etm_blinky_systimer.rs

@@ -0,0 +1,45 @@
+//! Control LED on GPIO 1 by the systimer via ETM
+
+#![no_std]
+#![no_main]
+
+use esp32h2_hal::{
+    clock::ClockControl,
+    etm::Etm,
+    gpio::{etm::GpioEtmChannels, IO},
+    peripherals::Peripherals,
+    prelude::*,
+    systimer::{etm::SysTimerEtmEvent, SystemTimer},
+};
+use esp_backtrace as _;
+
+#[entry]
+fn main() -> ! {
+    esp_println::logger::init_logger_from_env();
+    let peripherals = Peripherals::take();
+    let system = peripherals.PCR.split();
+    let _clocks = ClockControl::boot_defaults(system.clock_control).freeze();
+
+    let syst = SystemTimer::new(peripherals.SYSTIMER);
+    let mut alarm0 = syst.alarm0.into_periodic();
+    alarm0.set_period(1u32.secs());
+
+    let io = IO::new(peripherals.GPIO, peripherals.IO_MUX);
+    let mut led = io.pins.gpio1.into_push_pull_output();
+
+    // setup ETM
+    let gpio_ext = GpioEtmChannels::new(peripherals.GPIO_SD);
+    let led_task = gpio_ext.channel0_task.toggle(&mut led);
+
+    let timer_event = SysTimerEtmEvent::new(&mut alarm0);
+
+    let etm = Etm::new(peripherals.SOC_ETM);
+    let channel0 = etm.channel0;
+
+    // make sure the configured channel doesn't get dropped - dropping it will
+    // disable the channel
+    let _configured_channel = channel0.setup(&timer_event, &led_task);
+
+    // the LED is controlled by the timer without involving the CPU
+    loop {}
+}