From 3e31b93c195b45accc0096814cec8bc783417aee Mon Sep 17 00:00:00 2001
From: Alexandre Levy <a13xlevy@pm.me>
Date: Wed, 13 Mar 2024 22:00:33 +0000
Subject: [PATCH 01/16] Implement ETM for general purpose timers

---
 esp-hal/src/embassy/time_driver_timg.rs |  10 +-
 esp-hal/src/soc/esp32c6/mod.rs          |   4 +-
 esp-hal/src/timer.rs                    | 140 ++++++++++++++++++------
 examples/src/bin/timer_interrupt.rs     |  19 +++-
 4 files changed, 133 insertions(+), 40 deletions(-)

diff --git a/esp-hal/src/embassy/time_driver_timg.rs b/esp-hal/src/embassy/time_driver_timg.rs
index e0df9fe8a9f..06e3b95ddb2 100644
--- a/esp-hal/src/embassy/time_driver_timg.rs
+++ b/esp-hal/src/embassy/time_driver_timg.rs
@@ -16,7 +16,7 @@ pub const ALARM_COUNT: usize = 1;
 #[cfg(any(esp32, esp32s2, esp32s3))]
 pub const ALARM_COUNT: usize = 2;
 
-pub type TimerType = TimerGroup<'static, TIMG0>;
+pub type TimerType = TimerGroup<'static, TIMG0, 0>;
 
 pub struct EmbassyTimer {
     pub(crate) alarms: Mutex<[AlarmState; ALARM_COUNT]>,
@@ -30,7 +30,7 @@ embassy_time_driver::time_driver_impl!(static DRIVER: EmbassyTimer = EmbassyTime
 
 impl EmbassyTimer {
     pub(crate) fn now() -> u64 {
-        unsafe { Timer0::<TIMG0>::steal() }.now()
+        unsafe { Timer0::<TIMG0, 0>::steal() }.now()
     }
 
     fn trigger_alarm(&self, n: usize, cs: CriticalSection) {
@@ -77,7 +77,7 @@ impl EmbassyTimer {
 
         #[interrupt]
         fn TG0_T0_LEVEL() {
-            let timer = unsafe { Timer0::<TIMG0>::steal() };
+            let timer = unsafe { Timer0::<TIMG0, 0>::steal() };
             DRIVER.on_interrupt(0, timer);
         }
 
@@ -100,12 +100,12 @@ impl EmbassyTimer {
             // critical section.
             #[cfg(any(esp32, esp32s2, esp32s3))]
             if _alarm.id() == 1 {
-                let mut tg = unsafe { Timer1::<TIMG0>::steal() };
+                let mut tg = unsafe { Timer1::<TIMG0, 0>::steal() };
                 Self::arm(&mut tg, timestamp);
                 return;
             }
 
-            let mut tg = unsafe { Timer0::<TIMG0>::steal() };
+            let mut tg = unsafe { Timer0::<TIMG0, 0>::steal() };
             Self::arm(&mut tg, timestamp);
         });
 
diff --git a/esp-hal/src/soc/esp32c6/mod.rs b/esp-hal/src/soc/esp32c6/mod.rs
index 5e839472323..24bf3917611 100644
--- a/esp-hal/src/soc/esp32c6/mod.rs
+++ b/esp-hal/src/soc/esp32c6/mod.rs
@@ -49,6 +49,6 @@ unsafe fn post_init() {
     rtc.swd.disable();
     rtc.rwdt.disable();
 
-    Wdt::<TIMG0>::set_wdt_enabled(false);
-    Wdt::<TIMG1>::set_wdt_enabled(false);
+    Wdt::<TIMG0, 0>::set_wdt_enabled(false);
+    Wdt::<TIMG1, 1>::set_wdt_enabled(false);
 }
diff --git a/esp-hal/src/timer.rs b/esp-hal/src/timer.rs
index e4e293674c0..2918fc46c12 100644
--- a/esp-hal/src/timer.rs
+++ b/esp-hal/src/timer.rs
@@ -68,24 +68,24 @@ pub enum Error {
 
 // A timergroup consisting of up to 2 timers (chip dependent) and a watchdog
 // timer
-pub struct TimerGroup<'d, T>
+pub struct TimerGroup<'d, T, const G: u8>
 where
-    T: TimerGroupInstance,
+    T: TimerGroupInstance<G>,
 {
     _timer_group: PeripheralRef<'d, T>,
-    pub timer0: Timer<Timer0<T>>,
+    pub timer0: Timer<Timer0<T, G>>,
     #[cfg(not(any(esp32c2, esp32c3, esp32c6, esp32h2)))]
     pub timer1: Timer<Timer1<T>>,
-    pub wdt: Wdt<T>,
+    pub wdt: Wdt<T, G>,
 }
 
-pub trait TimerGroupInstance {
+pub trait TimerGroupInstance<const G: u8> {
     fn register_block() -> *const RegisterBlock;
     fn configure_src_clk();
     fn configure_wdt_src_clk();
 }
 
-impl TimerGroupInstance for TIMG0 {
+impl TimerGroupInstance<0> for TIMG0 {
     #[inline(always)]
     fn register_block() -> *const RegisterBlock {
         crate::peripherals::TIMG0::PTR
@@ -135,7 +135,7 @@ impl TimerGroupInstance for TIMG0 {
 }
 
 #[cfg(timg1)]
-impl TimerGroupInstance for TIMG1 {
+impl TimerGroupInstance<1> for TIMG1 {
     #[inline(always)]
     fn register_block() -> *const RegisterBlock {
         crate::peripherals::TIMG1::PTR
@@ -177,9 +177,9 @@ impl TimerGroupInstance for TIMG1 {
     }
 }
 
-impl<'d, T> TimerGroup<'d, T>
+impl<'d, T, const G: u8> TimerGroup<'d, T, G>
 where
-    T: TimerGroupInstance,
+    T: TimerGroupInstance<G>,
 {
     pub fn new(timer_group: impl Peripheral<P = T> + 'd, clocks: &Clocks) -> Self {
         crate::into_ref!(timer_group);
@@ -296,13 +296,13 @@ pub trait Instance {
     fn enable_peripheral(&self);
 }
 
-pub struct Timer0<TG> {
+pub struct Timer0<TG, const G: u8> {
     phantom: PhantomData<TG>,
 }
 
-impl<TG> Timer0<TG>
+impl<TG, const G: u8> Timer0<TG, G>
 where
-    TG: TimerGroupInstance,
+    TG: TimerGroupInstance<G>,
 {
     #[allow(unused)]
     pub(crate) unsafe fn steal() -> Self {
@@ -313,9 +313,9 @@ where
 }
 
 /// Timer peripheral instance
-impl<TG> Instance for Timer0<TG>
+impl<TG, const G: u8> Instance for Timer0<TG, G>
 where
-    TG: TimerGroupInstance,
+    TG: TimerGroupInstance<G>,
 {
     fn reset_counter(&mut self) {
         let reg_block = unsafe { &*TG::register_block() };
@@ -465,14 +465,14 @@ where
 }
 
 #[cfg(not(any(esp32c2, esp32c3, esp32c6, esp32h2)))]
-pub struct Timer1<TG> {
-    phantom: PhantomData<TG>,
+pub struct Timer1<TG, const G: u8> {
+    phantom: PhantomData<TG, G>,
 }
 
 #[cfg(not(any(esp32c2, esp32c3, esp32c6, esp32h2)))]
-impl<TG> Timer1<TG>
+impl<TG, const G: u8> Timer1<TG, G>
 where
-    TG: TimerGroupInstance,
+    TG: TimerGroupInstance<G>,
 {
     #[allow(unused)]
     pub(crate) unsafe fn steal() -> Self {
@@ -484,9 +484,9 @@ where
 
 /// Timer peripheral instance
 #[cfg(not(any(esp32c2, esp32c3, esp32c6, esp32h2)))]
-impl<TG> Instance for Timer1<TG>
+impl<TG, const G: u8> Instance for Timer1<TG, G>
 where
-    TG: TimerGroupInstance,
+    TG: TimerGroupInstance<G>,
 {
     fn reset_counter(&mut self) {
         let reg_block = unsafe { &*TG::register_block() };
@@ -715,14 +715,14 @@ where
 impl<T> Periodic for Timer<T> where T: Instance {}
 
 /// Watchdog timer
-pub struct Wdt<TG> {
+pub struct Wdt<TG, const G: u8> {
     phantom: PhantomData<TG>,
 }
 
 /// Watchdog driver
-impl<TG> Wdt<TG>
+impl<TG, const G: u8> Wdt<TG, G>
 where
-    TG: TimerGroupInstance,
+    TG: TimerGroupInstance<G>,
 {
     /// Create a new watchdog timer instance
     pub fn new() -> Self {
@@ -835,27 +835,27 @@ where
     }
 }
 
-impl<TG> Default for Wdt<TG>
+impl<TG, const G: u8> Default for Wdt<TG, G>
 where
-    TG: TimerGroupInstance,
+    TG: TimerGroupInstance<G>,
 {
     fn default() -> Self {
         Self::new()
     }
 }
 
-impl<TG> WatchdogDisable for Wdt<TG>
+impl<TG, const G: u8> WatchdogDisable for Wdt<TG, G>
 where
-    TG: TimerGroupInstance,
+    TG: TimerGroupInstance<G>,
 {
     fn disable(&mut self) {
         self.disable();
     }
 }
 
-impl<TG> WatchdogEnable for Wdt<TG>
+impl<TG, const G: u8> WatchdogEnable for Wdt<TG, G>
 where
-    TG: TimerGroupInstance,
+    TG: TimerGroupInstance<G>,
 {
     type Time = MicrosDurationU64;
 
@@ -868,11 +868,89 @@ where
     }
 }
 
-impl<TG> Watchdog for Wdt<TG>
+impl<TG, const G: u8> Watchdog for Wdt<TG, G>
 where
-    TG: TimerGroupInstance,
+    TG: TimerGroupInstance<G>,
 {
     fn feed(&mut self) {
         self.feed();
     }
 }
+
+#[cfg(soc_etm)]
+pub mod etm {
+    use super::*;
+    use crate::{
+        etm::{EtmEvent, EtmTask},
+        private::Sealed,
+    };
+
+    pub struct TimerEtmEvent {
+        id: u8,
+    }
+
+    pub struct TimerEtmTask {
+        id: u8,
+    }
+
+    impl EtmEvent for TimerEtmEvent {
+        fn id(&self) -> u8 {
+            self.id
+        }
+    }
+
+    impl Sealed for TimerEtmEvent {}
+
+    impl EtmTask for TimerEtmTask {
+        fn id(&self) -> u8 {
+            self.id
+        }
+    }
+
+    impl Sealed for TimerEtmTask {}
+
+    pub trait TimerEtmEvents<TG, const G: u8> {
+        fn on_alarm(&self) -> TimerEtmEvent;
+    }
+
+    pub trait TimerEtmTasks<TG, const G: u8> {
+        fn cnt_start(&self) -> TimerEtmTask;
+        fn cnt_stop(&self) -> TimerEtmTask;
+        fn cnt_reload(&self) -> TimerEtmTask;
+        fn cnt_cap(&self) -> TimerEtmTask;
+        fn alarm_start(&self) -> TimerEtmTask;
+    }
+
+    impl<TG, const G: u8> TimerEtmEvents<TG, G> for Timer0<TG, G>
+    where
+        TG: TimerGroupInstance<G>,
+    {
+        fn on_alarm(&self) -> TimerEtmEvent {
+            TimerEtmEvent { id: 48 + G }
+        }
+    }
+
+    impl<TG, const G: u8> TimerEtmTasks<TG, G> for Timer0<TG, G>
+    where
+        TG: TimerGroupInstance<G>,
+    {
+        fn cnt_start(&self) -> TimerEtmTask {
+            TimerEtmTask { id: 88 + G }
+        }
+
+        fn alarm_start(&self) -> TimerEtmTask {
+            TimerEtmTask { id: 90 + G }
+        }
+
+        fn cnt_stop(&self) -> TimerEtmTask {
+            TimerEtmTask { id: 92 + G }
+        }
+
+        fn cnt_reload(&self) -> TimerEtmTask {
+            TimerEtmTask { id: 94 + G }
+        }
+        fn cnt_cap(&self) -> TimerEtmTask {
+            TimerEtmTask { id: 96 + G }
+        }
+    }
+}
diff --git a/examples/src/bin/timer_interrupt.rs b/examples/src/bin/timer_interrupt.rs
index 62e4194f94a..91cc3c68adf 100644
--- a/examples/src/bin/timer_interrupt.rs
+++ b/examples/src/bin/timer_interrupt.rs
@@ -13,13 +13,19 @@ use critical_section::Mutex;
 use esp_backtrace as _;
 use esp_hal::{
     clock::ClockControl,
+    etm::Etm,
     interrupt::{self, Priority},
     peripherals::{Interrupt, Peripherals, TIMG0},
     prelude::*,
-    timer::{Timer, Timer0, TimerGroup},
+    timer::{
+        etm::{TimerEtmEvents, TimerEtmTasks},
+        Timer,
+        Timer0,
+        TimerGroup,
+    },
 };
 
-static TIMER0: Mutex<RefCell<Option<Timer<Timer0<TIMG0>>>>> = Mutex::new(RefCell::new(None));
+static TIMER0: Mutex<RefCell<Option<Timer<Timer0<TIMG0, 0>>>>> = Mutex::new(RefCell::new(None));
 
 #[entry]
 fn main() -> ! {
@@ -30,6 +36,15 @@ fn main() -> ! {
     let timg0 = TimerGroup::new(peripherals.TIMG0, &clocks);
     let mut timer0 = timg0.timer0;
 
+    let ev = timer0.on_alarm();
+    let tsk = timer0.cnt_start();
+
+    let etm = Etm::new(peripherals.SOC_ETM);
+
+    let chan0 = etm.channel0;
+
+    chan0.setup(&ev, &tsk);
+
     interrupt::enable(Interrupt::TG0_T0_LEVEL, Priority::Priority1).unwrap();
     timer0.start(500u64.millis());
     timer0.listen();

From c39d26ad12239a3640469704cb5714b681fe7646 Mon Sep 17 00:00:00 2001
From: Alexandre Levy <a13xlevy@pm.me>
Date: Wed, 13 Mar 2024 22:14:25 +0000
Subject: [PATCH 02/16] Revert changes to timer_interrupt example

---
 examples/src/bin/timer_interrupt.rs | 19 ++-----------------
 1 file changed, 2 insertions(+), 17 deletions(-)

diff --git a/examples/src/bin/timer_interrupt.rs b/examples/src/bin/timer_interrupt.rs
index 91cc3c68adf..62e4194f94a 100644
--- a/examples/src/bin/timer_interrupt.rs
+++ b/examples/src/bin/timer_interrupt.rs
@@ -13,19 +13,13 @@ use critical_section::Mutex;
 use esp_backtrace as _;
 use esp_hal::{
     clock::ClockControl,
-    etm::Etm,
     interrupt::{self, Priority},
     peripherals::{Interrupt, Peripherals, TIMG0},
     prelude::*,
-    timer::{
-        etm::{TimerEtmEvents, TimerEtmTasks},
-        Timer,
-        Timer0,
-        TimerGroup,
-    },
+    timer::{Timer, Timer0, TimerGroup},
 };
 
-static TIMER0: Mutex<RefCell<Option<Timer<Timer0<TIMG0, 0>>>>> = Mutex::new(RefCell::new(None));
+static TIMER0: Mutex<RefCell<Option<Timer<Timer0<TIMG0>>>>> = Mutex::new(RefCell::new(None));
 
 #[entry]
 fn main() -> ! {
@@ -36,15 +30,6 @@ fn main() -> ! {
     let timg0 = TimerGroup::new(peripherals.TIMG0, &clocks);
     let mut timer0 = timg0.timer0;
 
-    let ev = timer0.on_alarm();
-    let tsk = timer0.cnt_start();
-
-    let etm = Etm::new(peripherals.SOC_ETM);
-
-    let chan0 = etm.channel0;
-
-    chan0.setup(&ev, &tsk);
-
     interrupt::enable(Interrupt::TG0_T0_LEVEL, Priority::Priority1).unwrap();
     timer0.start(500u64.millis());
     timer0.listen();

From c17f93c44c15d0861686ad7a3906aa64c74a04e4 Mon Sep 17 00:00:00 2001
From: Alexandre Levy <a13xlevy@pm.me>
Date: Wed, 13 Mar 2024 22:41:22 +0000
Subject: [PATCH 03/16] Add an example for ETM for general purpose timers

---
 examples/src/bin/etm_timer.rs | 72 +++++++++++++++++++++++++++++++++++
 1 file changed, 72 insertions(+)
 create mode 100644 examples/src/bin/etm_timer.rs

diff --git a/examples/src/bin/etm_timer.rs b/examples/src/bin/etm_timer.rs
new file mode 100644
index 00000000000..ecefcc6ed76
--- /dev/null
+++ b/examples/src/bin/etm_timer.rs
@@ -0,0 +1,72 @@
+//! This shows how to use the general purpose timers ETM tasks and events
+//! Notice you need to import the traits esp_hal::timer::etm::{TimerEtmEvents, TimerEtmTasks}
+//!
+//! CHIPS: esp32c6
+
+#![no_std]
+#![no_main]
+
+use core::cell::RefCell;
+
+use critical_section::{CriticalSection, Mutex};
+use esp_backtrace as _;
+use esp_hal::{
+    clock::ClockControl,
+    etm::Etm,
+    interrupt::{self, Priority},
+    peripherals::{Interrupt, Peripherals, TIMG0},
+    prelude::*,
+    timer::{
+        etm::{TimerEtmEvents, TimerEtmTasks},
+        Timer,
+        Timer0,
+        TimerGroup,
+    },
+};
+
+static TIMER0: Mutex<RefCell<Option<Timer<Timer0<TIMG0, 0>>>>> = Mutex::new(RefCell::new(None));
+
+#[entry]
+fn main() -> ! {
+    let peripherals = Peripherals::take();
+    let system = peripherals.SYSTEM.split();
+    let clocks = ClockControl::boot_defaults(system.clock_control).freeze();
+
+    let timg0 = TimerGroup::new(peripherals.TIMG0, &clocks);
+    let mut timer0 = timg0.timer0;
+
+    interrupt::enable(Interrupt::TG0_T0_LEVEL, Priority::Priority1).unwrap();
+
+    // Alarm at 100ms (80 clock cycles in 1 us)
+    timer0.load_alarm_value(100 * 1_000 * 80);
+    timer0.set_alarm_active(true);
+
+    let event = timer0.on_alarm();
+    let task = timer0.cnt_stop();
+
+    let etm = Etm::new(peripherals.SOC_ETM);
+
+    let channel0 = etm.channel0;
+
+    channel0.setup(&event, &task);
+
+    timer0.set_counter_active(true);
+
+    critical_section::with(|cs| {
+        TIMER0.borrow_ref_mut(cs).replace(timer0);
+    });
+
+    loop {}
+}
+
+#[interrupt]
+fn TG0_T0_LEVEL() {
+    critical_section::with(|cs| {
+        let mut timer0 = TIMER0.borrow_ref_mut(cs);
+        let timer0 = timer0.as_mut().unwrap();
+
+        timer0.clear_interrupt();
+
+        esp_println::println!("Counter: {}", timer0.now());
+    });
+}

From 218a321fb3acd847196a3f2c031d4a90331f331d Mon Sep 17 00:00:00 2001
From: Alexandre Levy <a13xlevy@pm.me>
Date: Wed, 13 Mar 2024 22:42:01 +0000
Subject: [PATCH 04/16] Add newly introduced generic const param for Timer0

---
 examples/src/bin/timer_interrupt.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/examples/src/bin/timer_interrupt.rs b/examples/src/bin/timer_interrupt.rs
index 62e4194f94a..9de28ff8d74 100644
--- a/examples/src/bin/timer_interrupt.rs
+++ b/examples/src/bin/timer_interrupt.rs
@@ -19,7 +19,7 @@ use esp_hal::{
     timer::{Timer, Timer0, TimerGroup},
 };
 
-static TIMER0: Mutex<RefCell<Option<Timer<Timer0<TIMG0>>>>> = Mutex::new(RefCell::new(None));
+static TIMER0: Mutex<RefCell<Option<Timer<Timer0<TIMG0, 0>>>>> = Mutex::new(RefCell::new(None));
 
 #[entry]
 fn main() -> ! {

From 0d055c07e4ac59fb9333febec021720a07a0972a Mon Sep 17 00:00:00 2001
From: Alex Levy <a13xlevy@pm.me>
Date: Thu, 14 Mar 2024 12:34:57 +0000
Subject: [PATCH 05/16] Use id function on TimerGroupInstance instead of const
 parameter

---
 esp-hal/src/embassy/time_driver_timg.rs |  8 +--
 esp-hal/src/soc/esp32c6/mod.rs          |  4 +-
 esp-hal/src/timer.rs                    | 93 +++++++++++++------------
 examples/src/bin/etm_timer.rs           |  2 +-
 examples/src/bin/timer_interrupt.rs     |  2 +-
 5 files changed, 58 insertions(+), 51 deletions(-)

diff --git a/esp-hal/src/embassy/time_driver_timg.rs b/esp-hal/src/embassy/time_driver_timg.rs
index 06e3b95ddb2..fc4d4d491ab 100644
--- a/esp-hal/src/embassy/time_driver_timg.rs
+++ b/esp-hal/src/embassy/time_driver_timg.rs
@@ -16,7 +16,7 @@ pub const ALARM_COUNT: usize = 1;
 #[cfg(any(esp32, esp32s2, esp32s3))]
 pub const ALARM_COUNT: usize = 2;
 
-pub type TimerType = TimerGroup<'static, TIMG0, 0>;
+pub type TimerType = TimerGroup<'static, TIMG0>;
 
 pub struct EmbassyTimer {
     pub(crate) alarms: Mutex<[AlarmState; ALARM_COUNT]>,
@@ -30,7 +30,7 @@ embassy_time_driver::time_driver_impl!(static DRIVER: EmbassyTimer = EmbassyTime
 
 impl EmbassyTimer {
     pub(crate) fn now() -> u64 {
-        unsafe { Timer0::<TIMG0, 0>::steal() }.now()
+        unsafe { Timer0::<TIMG0>::steal() }.now()
     }
 
     fn trigger_alarm(&self, n: usize, cs: CriticalSection) {
@@ -77,7 +77,7 @@ impl EmbassyTimer {
 
         #[interrupt]
         fn TG0_T0_LEVEL() {
-            let timer = unsafe { Timer0::<TIMG0, 0>::steal() };
+            let timer = unsafe { Timer0::<TIMG0>::steal() };
             DRIVER.on_interrupt(0, timer);
         }
 
@@ -105,7 +105,7 @@ impl EmbassyTimer {
                 return;
             }
 
-            let mut tg = unsafe { Timer0::<TIMG0, 0>::steal() };
+            let mut tg = unsafe { Timer0::<TIMG0>::steal() };
             Self::arm(&mut tg, timestamp);
         });
 
diff --git a/esp-hal/src/soc/esp32c6/mod.rs b/esp-hal/src/soc/esp32c6/mod.rs
index 8efdb21244a..96e22cf7c28 100644
--- a/esp-hal/src/soc/esp32c6/mod.rs
+++ b/esp-hal/src/soc/esp32c6/mod.rs
@@ -49,6 +49,6 @@ unsafe fn post_init() {
     rtc.swd.disable();
     rtc.rwdt.disable();
 
-    Wdt::<TIMG0, 0>::set_wdt_enabled(false);
-    Wdt::<TIMG1, 1>::set_wdt_enabled(false);
+    Wdt::<TIMG0>::set_wdt_enabled(false);
+    Wdt::<TIMG1>::set_wdt_enabled(false);
 }
diff --git a/esp-hal/src/timer.rs b/esp-hal/src/timer.rs
index 2918fc46c12..3547dd72376 100644
--- a/esp-hal/src/timer.rs
+++ b/esp-hal/src/timer.rs
@@ -68,24 +68,28 @@ pub enum Error {
 
 // A timergroup consisting of up to 2 timers (chip dependent) and a watchdog
 // timer
-pub struct TimerGroup<'d, T, const G: u8>
+pub struct TimerGroup<'d, T>
 where
-    T: TimerGroupInstance<G>,
+    T: TimerGroupInstance,
 {
     _timer_group: PeripheralRef<'d, T>,
-    pub timer0: Timer<Timer0<T, G>>,
+    pub timer0: Timer<Timer0<T>>,
     #[cfg(not(any(esp32c2, esp32c3, esp32c6, esp32h2)))]
     pub timer1: Timer<Timer1<T>>,
-    pub wdt: Wdt<T, G>,
+    pub wdt: Wdt<T>,
 }
 
-pub trait TimerGroupInstance<const G: u8> {
+pub trait TimerGroupInstance {
     fn register_block() -> *const RegisterBlock;
     fn configure_src_clk();
     fn configure_wdt_src_clk();
+    fn id() -> u8;
 }
 
-impl TimerGroupInstance<0> for TIMG0 {
+impl TimerGroupInstance for TIMG0 {
+    fn id() -> u8 {
+        0
+    }
     #[inline(always)]
     fn register_block() -> *const RegisterBlock {
         crate::peripherals::TIMG0::PTR
@@ -135,7 +139,10 @@ impl TimerGroupInstance<0> for TIMG0 {
 }
 
 #[cfg(timg1)]
-impl TimerGroupInstance<1> for TIMG1 {
+impl TimerGroupInstance for TIMG1 {
+    fn id() -> u8 {
+        1
+    }
     #[inline(always)]
     fn register_block() -> *const RegisterBlock {
         crate::peripherals::TIMG1::PTR
@@ -177,9 +184,9 @@ impl TimerGroupInstance<1> for TIMG1 {
     }
 }
 
-impl<'d, T, const G: u8> TimerGroup<'d, T, G>
+impl<'d, T> TimerGroup<'d, T>
 where
-    T: TimerGroupInstance<G>,
+    T: TimerGroupInstance,
 {
     pub fn new(timer_group: impl Peripheral<P = T> + 'd, clocks: &Clocks) -> Self {
         crate::into_ref!(timer_group);
@@ -296,13 +303,13 @@ pub trait Instance {
     fn enable_peripheral(&self);
 }
 
-pub struct Timer0<TG, const G: u8> {
+pub struct Timer0<TG> {
     phantom: PhantomData<TG>,
 }
 
-impl<TG, const G: u8> Timer0<TG, G>
+impl<TG> Timer0<TG>
 where
-    TG: TimerGroupInstance<G>,
+    TG: TimerGroupInstance,
 {
     #[allow(unused)]
     pub(crate) unsafe fn steal() -> Self {
@@ -313,9 +320,9 @@ where
 }
 
 /// Timer peripheral instance
-impl<TG, const G: u8> Instance for Timer0<TG, G>
+impl<TG> Instance for Timer0<TG>
 where
-    TG: TimerGroupInstance<G>,
+    TG: TimerGroupInstance,
 {
     fn reset_counter(&mut self) {
         let reg_block = unsafe { &*TG::register_block() };
@@ -465,14 +472,14 @@ where
 }
 
 #[cfg(not(any(esp32c2, esp32c3, esp32c6, esp32h2)))]
-pub struct Timer1<TG, const G: u8> {
-    phantom: PhantomData<TG, G>,
+pub struct Timer1<TG> {
+    phantom: PhantomData<TG>,
 }
 
 #[cfg(not(any(esp32c2, esp32c3, esp32c6, esp32h2)))]
-impl<TG, const G: u8> Timer1<TG, G>
+impl<TG> Timer1<TG>
 where
-    TG: TimerGroupInstance<G>,
+    TG: TimerGroupInstance,
 {
     #[allow(unused)]
     pub(crate) unsafe fn steal() -> Self {
@@ -484,9 +491,9 @@ where
 
 /// Timer peripheral instance
 #[cfg(not(any(esp32c2, esp32c3, esp32c6, esp32h2)))]
-impl<TG, const G: u8> Instance for Timer1<TG, G>
+impl<TG> Instance for Timer1<TG>
 where
-    TG: TimerGroupInstance<G>,
+    TG: TimerGroupInstance,
 {
     fn reset_counter(&mut self) {
         let reg_block = unsafe { &*TG::register_block() };
@@ -715,14 +722,14 @@ where
 impl<T> Periodic for Timer<T> where T: Instance {}
 
 /// Watchdog timer
-pub struct Wdt<TG, const G: u8> {
+pub struct Wdt<TG> {
     phantom: PhantomData<TG>,
 }
 
 /// Watchdog driver
-impl<TG, const G: u8> Wdt<TG, G>
+impl<TG> Wdt<TG>
 where
-    TG: TimerGroupInstance<G>,
+    TG: TimerGroupInstance,
 {
     /// Create a new watchdog timer instance
     pub fn new() -> Self {
@@ -835,27 +842,27 @@ where
     }
 }
 
-impl<TG, const G: u8> Default for Wdt<TG, G>
+impl<TG> Default for Wdt<TG>
 where
-    TG: TimerGroupInstance<G>,
+    TG: TimerGroupInstance,
 {
     fn default() -> Self {
         Self::new()
     }
 }
 
-impl<TG, const G: u8> WatchdogDisable for Wdt<TG, G>
+impl<TG> WatchdogDisable for Wdt<TG>
 where
-    TG: TimerGroupInstance<G>,
+    TG: TimerGroupInstance,
 {
     fn disable(&mut self) {
         self.disable();
     }
 }
 
-impl<TG, const G: u8> WatchdogEnable for Wdt<TG, G>
+impl<TG> WatchdogEnable for Wdt<TG>
 where
-    TG: TimerGroupInstance<G>,
+    TG: TimerGroupInstance,
 {
     type Time = MicrosDurationU64;
 
@@ -868,9 +875,9 @@ where
     }
 }
 
-impl<TG, const G: u8> Watchdog for Wdt<TG, G>
+impl<TG> Watchdog for Wdt<TG>
 where
-    TG: TimerGroupInstance<G>,
+    TG: TimerGroupInstance,
 {
     fn feed(&mut self) {
         self.feed();
@@ -909,11 +916,11 @@ pub mod etm {
 
     impl Sealed for TimerEtmTask {}
 
-    pub trait TimerEtmEvents<TG, const G: u8> {
+    pub trait TimerEtmEvents<TG> {
         fn on_alarm(&self) -> TimerEtmEvent;
     }
 
-    pub trait TimerEtmTasks<TG, const G: u8> {
+    pub trait TimerEtmTasks<TG> {
         fn cnt_start(&self) -> TimerEtmTask;
         fn cnt_stop(&self) -> TimerEtmTask;
         fn cnt_reload(&self) -> TimerEtmTask;
@@ -921,36 +928,36 @@ pub mod etm {
         fn alarm_start(&self) -> TimerEtmTask;
     }
 
-    impl<TG, const G: u8> TimerEtmEvents<TG, G> for Timer0<TG, G>
+    impl<TG> TimerEtmEvents<TG> for Timer0<TG>
     where
-        TG: TimerGroupInstance<G>,
+        TG: TimerGroupInstance,
     {
         fn on_alarm(&self) -> TimerEtmEvent {
-            TimerEtmEvent { id: 48 + G }
+            TimerEtmEvent { id: 48 + TG::id() }
         }
     }
 
-    impl<TG, const G: u8> TimerEtmTasks<TG, G> for Timer0<TG, G>
+    impl<TG> TimerEtmTasks<TG> for Timer0<TG>
     where
-        TG: TimerGroupInstance<G>,
+        TG: TimerGroupInstance,
     {
         fn cnt_start(&self) -> TimerEtmTask {
-            TimerEtmTask { id: 88 + G }
+            TimerEtmTask { id: 88 + TG::id() }
         }
 
         fn alarm_start(&self) -> TimerEtmTask {
-            TimerEtmTask { id: 90 + G }
+            TimerEtmTask { id: 90 + TG::id() }
         }
 
         fn cnt_stop(&self) -> TimerEtmTask {
-            TimerEtmTask { id: 92 + G }
+            TimerEtmTask { id: 92 + TG::id() }
         }
 
         fn cnt_reload(&self) -> TimerEtmTask {
-            TimerEtmTask { id: 94 + G }
+            TimerEtmTask { id: 94 + TG::id() }
         }
         fn cnt_cap(&self) -> TimerEtmTask {
-            TimerEtmTask { id: 96 + G }
+            TimerEtmTask { id: 96 + TG::id() }
         }
     }
 }
diff --git a/examples/src/bin/etm_timer.rs b/examples/src/bin/etm_timer.rs
index ecefcc6ed76..b260e8362f4 100644
--- a/examples/src/bin/etm_timer.rs
+++ b/examples/src/bin/etm_timer.rs
@@ -24,7 +24,7 @@ use esp_hal::{
     },
 };
 
-static TIMER0: Mutex<RefCell<Option<Timer<Timer0<TIMG0, 0>>>>> = Mutex::new(RefCell::new(None));
+static TIMER0: Mutex<RefCell<Option<Timer<Timer0<TIMG0>>>>> = Mutex::new(RefCell::new(None));
 
 #[entry]
 fn main() -> ! {
diff --git a/examples/src/bin/timer_interrupt.rs b/examples/src/bin/timer_interrupt.rs
index 9de28ff8d74..62e4194f94a 100644
--- a/examples/src/bin/timer_interrupt.rs
+++ b/examples/src/bin/timer_interrupt.rs
@@ -19,7 +19,7 @@ use esp_hal::{
     timer::{Timer, Timer0, TimerGroup},
 };
 
-static TIMER0: Mutex<RefCell<Option<Timer<Timer0<TIMG0, 0>>>>> = Mutex::new(RefCell::new(None));
+static TIMER0: Mutex<RefCell<Option<Timer<Timer0<TIMG0>>>>> = Mutex::new(RefCell::new(None));
 
 #[entry]
 fn main() -> ! {

From 799bf56bdf5728ca67da8515e62b6c0ae13289a2 Mon Sep 17 00:00:00 2001
From: Alex Levy <a13xlevy@pm.me>
Date: Thu, 14 Mar 2024 12:38:24 +0000
Subject: [PATCH 06/16] Revert const parameter on Timer1

---
 esp-hal/src/embassy/time_driver_timg.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/esp-hal/src/embassy/time_driver_timg.rs b/esp-hal/src/embassy/time_driver_timg.rs
index fc4d4d491ab..e0df9fe8a9f 100644
--- a/esp-hal/src/embassy/time_driver_timg.rs
+++ b/esp-hal/src/embassy/time_driver_timg.rs
@@ -100,7 +100,7 @@ impl EmbassyTimer {
             // critical section.
             #[cfg(any(esp32, esp32s2, esp32s3))]
             if _alarm.id() == 1 {
-                let mut tg = unsafe { Timer1::<TIMG0, 0>::steal() };
+                let mut tg = unsafe { Timer1::<TIMG0>::steal() };
                 Self::arm(&mut tg, timestamp);
                 return;
             }

From c1d79b50c29ab2a8f401c5d16d68a061fafae9c3 Mon Sep 17 00:00:00 2001
From: Alex Levy <a13xlevy@pm.me>
Date: Thu, 14 Mar 2024 12:44:21 +0000
Subject: [PATCH 07/16] Specify supported chips

---
 examples/src/bin/etm_timer.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/examples/src/bin/etm_timer.rs b/examples/src/bin/etm_timer.rs
index b260e8362f4..dc7e645bee1 100644
--- a/examples/src/bin/etm_timer.rs
+++ b/examples/src/bin/etm_timer.rs
@@ -1,7 +1,7 @@
 //! This shows how to use the general purpose timers ETM tasks and events
 //! Notice you need to import the traits esp_hal::timer::etm::{TimerEtmEvents, TimerEtmTasks}
 //!
-//! CHIPS: esp32c6
+//% CHIPS: esp32h2 esp32c6
 
 #![no_std]
 #![no_main]

From a72c4147a30c22117226a538c4bdc5cff20db6a8 Mon Sep 17 00:00:00 2001
From: Alex Levy <a13xlevy@pm.me>
Date: Thu, 14 Mar 2024 12:48:25 +0000
Subject: [PATCH 08/16] Update CHANGELOG.md

---
 esp-hal/CHANGELOG.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/esp-hal/CHANGELOG.md b/esp-hal/CHANGELOG.md
index 24f0b800884..5b1d372a264 100644
--- a/esp-hal/CHANGELOG.md
+++ b/esp-hal/CHANGELOG.md
@@ -9,6 +9,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- Support `ETM` for ESP32-C6 / ESP32-H2 general purpose timers (#1274)
+
 ### Fixed
 
 - Fixing `esp-wifi` + `TRNG` issue on `ESP32-S2` (#1272)

From 8ef64e6edce77517f79ab895c0d0470567960fac Mon Sep 17 00:00:00 2001
From: Alex Levy <a13xlevy@pm.me>
Date: Thu, 14 Mar 2024 12:51:37 +0000
Subject: [PATCH 09/16] Update CHANGELOG.md

---
 esp-hal/CHANGELOG.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/esp-hal/CHANGELOG.md b/esp-hal/CHANGELOG.md
index 5b1d372a264..66960fc7287 100644
--- a/esp-hal/CHANGELOG.md
+++ b/esp-hal/CHANGELOG.md
@@ -9,7 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
-- Support `ETM` for ESP32-C6 / ESP32-H2 general purpose timers (#1274)
+- ESP32-C6 / ESP32-H2: Implement `ETM` for general purpose timers (#1274)
 
 ### Fixed
 

From 27324503ee1c2cd8ad28f1caa9014740a64edf76 Mon Sep 17 00:00:00 2001
From: Alex Levy <a13xlevy@pm.me>
Date: Thu, 14 Mar 2024 13:19:14 +0000
Subject: [PATCH 10/16] Fix example

---
 examples/src/bin/etm_timer.rs | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/examples/src/bin/etm_timer.rs b/examples/src/bin/etm_timer.rs
index dc7e645bee1..59bd73b02e9 100644
--- a/examples/src/bin/etm_timer.rs
+++ b/examples/src/bin/etm_timer.rs
@@ -35,12 +35,7 @@ fn main() -> ! {
     let timg0 = TimerGroup::new(peripherals.TIMG0, &clocks);
     let mut timer0 = timg0.timer0;
 
-    interrupt::enable(Interrupt::TG0_T0_LEVEL, Priority::Priority1).unwrap();
-
-    // Alarm at 100ms (80 clock cycles in 1 us)
-    timer0.load_alarm_value(100 * 1_000 * 80);
-    timer0.set_alarm_active(true);
-
+    // Configure ETM to stop timer0 when alarm is triggered
     let event = timer0.on_alarm();
     let task = timer0.cnt_stop();
 
@@ -50,8 +45,19 @@ fn main() -> ! {
 
     channel0.setup(&event, &task);
 
+    timer0.set_counter_decrementing(false);
+    timer0.reset_counter();
     timer0.set_counter_active(true);
 
+    // Setup alarm at 100ms
+    // 80 / 2 (default divider) timer clock cycles == 1 us
+    timer0.load_alarm_value(100 * 1_000 * 40);
+
+    // Enable interrupt that will be triggered by the alarm
+    interrupt::enable(Interrupt::TG0_T0_LEVEL, Priority::Priority1).unwrap();
+
+    timer0.set_alarm_active(true);
+
     critical_section::with(|cs| {
         TIMER0.borrow_ref_mut(cs).replace(timer0);
     });
@@ -67,6 +73,7 @@ fn TG0_T0_LEVEL() {
 
         timer0.clear_interrupt();
 
+        // This should display close to 4_000_000
         esp_println::println!("Counter: {}", timer0.now());
     });
 }

From 4a3e0921ff332f62e4e6ce12799690fc7a2e1a2e Mon Sep 17 00:00:00 2001
From: Alexandre Levy <a13xlevy@pm.me>
Date: Fri, 15 Mar 2024 01:32:45 +0000
Subject: [PATCH 11/16] Assign configured ETM channel to a variable to prevent
 drop

---
 examples/src/bin/etm_timer.rs | 34 ++++++++++++++++++++++------------
 1 file changed, 22 insertions(+), 12 deletions(-)

diff --git a/examples/src/bin/etm_timer.rs b/examples/src/bin/etm_timer.rs
index 59bd73b02e9..cadacbb13e3 100644
--- a/examples/src/bin/etm_timer.rs
+++ b/examples/src/bin/etm_timer.rs
@@ -1,17 +1,18 @@
 //! This shows how to use the general purpose timers ETM tasks and events
 //! Notice you need to import the traits esp_hal::timer::etm::{TimerEtmEvents, TimerEtmTasks}
-//!
-//% CHIPS: esp32h2 esp32c6
+
+//% CHIPS: esp32c6 esp32h2
 
 #![no_std]
 #![no_main]
 
 use core::cell::RefCell;
 
-use critical_section::{CriticalSection, Mutex};
+use critical_section::Mutex;
 use esp_backtrace as _;
 use esp_hal::{
     clock::ClockControl,
+    delay::Delay,
     etm::Etm,
     interrupt::{self, Priority},
     peripherals::{Interrupt, Peripherals, TIMG0},
@@ -32,6 +33,8 @@ fn main() -> ! {
     let system = peripherals.SYSTEM.split();
     let clocks = ClockControl::boot_defaults(system.clock_control).freeze();
 
+    let mut delay = Delay::new(&clocks);
+
     let timg0 = TimerGroup::new(peripherals.TIMG0, &clocks);
     let mut timer0 = timg0.timer0;
 
@@ -43,26 +46,33 @@ fn main() -> ! {
 
     let channel0 = etm.channel0;
 
-    channel0.setup(&event, &task);
-
-    timer0.set_counter_decrementing(false);
-    timer0.reset_counter();
-    timer0.set_counter_active(true);
+    let _configured_channel = channel0.setup(&event, &task);
 
     // Setup alarm at 100ms
     // 80 / 2 (default divider) timer clock cycles == 1 us
     timer0.load_alarm_value(100 * 1_000 * 40);
+    timer0.set_alarm_active(true);
 
     // Enable interrupt that will be triggered by the alarm
     interrupt::enable(Interrupt::TG0_T0_LEVEL, Priority::Priority1).unwrap();
 
-    timer0.set_alarm_active(true);
+    timer0.listen();
+    timer0.set_counter_active(true);
 
     critical_section::with(|cs| {
         TIMER0.borrow_ref_mut(cs).replace(timer0);
     });
 
-    loop {}
+    loop {
+        delay.delay_ms(500u32);
+
+        critical_section::with(|cs| {
+            let mut timer0 = TIMER0.borrow_ref_mut(cs);
+            let timer0 = timer0.as_mut().unwrap();
+            // Counter value should be the same than in interrupt because we configured ETM to stop the timer on alarm
+            esp_println::println!("counter in main: {}", timer0.now());
+        });
+    }
 }
 
 #[interrupt]
@@ -73,7 +83,7 @@ fn TG0_T0_LEVEL() {
 
         timer0.clear_interrupt();
 
-        // This should display close to 4_000_000
-        esp_println::println!("Counter: {}", timer0.now());
+        // Counter value should be a very small number
+        esp_println::println!("counter in interrupt: {}", timer0.now());
     });
 }

From 228cebd543faa5108a447dcfb5ea956056fc06d4 Mon Sep 17 00:00:00 2001
From: Alexandre Levy <a13xlevy@pm.me>
Date: Fri, 15 Mar 2024 01:50:00 +0000
Subject: [PATCH 12/16] Fix comments

---
 examples/src/bin/etm_timer.rs | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/examples/src/bin/etm_timer.rs b/examples/src/bin/etm_timer.rs
index cadacbb13e3..b7e50e8bda9 100644
--- a/examples/src/bin/etm_timer.rs
+++ b/examples/src/bin/etm_timer.rs
@@ -69,7 +69,7 @@ fn main() -> ! {
         critical_section::with(|cs| {
             let mut timer0 = TIMER0.borrow_ref_mut(cs);
             let timer0 = timer0.as_mut().unwrap();
-            // Counter value should be the same than in interrupt because we configured ETM to stop the timer on alarm
+            // Counter value should be the same than in interrupt
             esp_println::println!("counter in main: {}", timer0.now());
         });
     }
@@ -83,7 +83,8 @@ fn TG0_T0_LEVEL() {
 
         timer0.clear_interrupt();
 
-        // Counter value should be a very small number
+        // Counter value should be a very small number as the alarm triggered a counter reload to 0
+        // and ETM stopped the counter quickly after
         esp_println::println!("counter in interrupt: {}", timer0.now());
     });
 }

From 73ca5d2e89d526aacb91a00f11f0d1efed8fd721 Mon Sep 17 00:00:00 2001
From: Alexandre Levy <a13xlevy@pm.me>
Date: Fri, 15 Mar 2024 02:03:54 +0000
Subject: [PATCH 13/16] Move declaration of delay after critical section

---
 examples/src/bin/etm_timer.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/examples/src/bin/etm_timer.rs b/examples/src/bin/etm_timer.rs
index b7e50e8bda9..7708f823a82 100644
--- a/examples/src/bin/etm_timer.rs
+++ b/examples/src/bin/etm_timer.rs
@@ -33,8 +33,6 @@ fn main() -> ! {
     let system = peripherals.SYSTEM.split();
     let clocks = ClockControl::boot_defaults(system.clock_control).freeze();
 
-    let mut delay = Delay::new(&clocks);
-
     let timg0 = TimerGroup::new(peripherals.TIMG0, &clocks);
     let mut timer0 = timg0.timer0;
 
@@ -63,6 +61,8 @@ fn main() -> ! {
         TIMER0.borrow_ref_mut(cs).replace(timer0);
     });
 
+    let mut delay = Delay::new(&clocks);
+
     loop {
         delay.delay_ms(500u32);
 

From 20ea0d193e2c6b4977bbab0405a5d39082085b3a Mon Sep 17 00:00:00 2001
From: Alexandre Levy <a13xlevy@pm.me>
Date: Fri, 15 Mar 2024 10:05:18 +0000
Subject: [PATCH 14/16] Use delay_millis instead of delay_ms

---
 examples/src/bin/etm_timer.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/examples/src/bin/etm_timer.rs b/examples/src/bin/etm_timer.rs
index 7708f823a82..96296fb5cb1 100644
--- a/examples/src/bin/etm_timer.rs
+++ b/examples/src/bin/etm_timer.rs
@@ -64,7 +64,7 @@ fn main() -> ! {
     let mut delay = Delay::new(&clocks);
 
     loop {
-        delay.delay_ms(500u32);
+        delay.delay_millis(500u32);
 
         critical_section::with(|cs| {
             let mut timer0 = TIMER0.borrow_ref_mut(cs);

From eb2d58c17fd86c150aafb4cf6b087933eb678ec1 Mon Sep 17 00:00:00 2001
From: Alexandre Levy <a13xlevy@pm.me>
Date: Fri, 15 Mar 2024 10:13:43 +0000
Subject: [PATCH 15/16] Remove mut from delay

---
 examples/src/bin/etm_timer.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/examples/src/bin/etm_timer.rs b/examples/src/bin/etm_timer.rs
index 96296fb5cb1..391e08942c3 100644
--- a/examples/src/bin/etm_timer.rs
+++ b/examples/src/bin/etm_timer.rs
@@ -61,7 +61,7 @@ fn main() -> ! {
         TIMER0.borrow_ref_mut(cs).replace(timer0);
     });
 
-    let mut delay = Delay::new(&clocks);
+    let delay = Delay::new(&clocks);
 
     loop {
         delay.delay_millis(500u32);

From b6d730268cde4ce98347420dd4f9f17ebf1e2d5e Mon Sep 17 00:00:00 2001
From: Alexandre Levy <a13xlevy@pm.me>
Date: Fri, 15 Mar 2024 10:24:15 +0000
Subject: [PATCH 16/16] Add documentation

---
 esp-hal/src/timer.rs | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/esp-hal/src/timer.rs b/esp-hal/src/timer.rs
index f3721f45938..ad97998c5c9 100644
--- a/esp-hal/src/timer.rs
+++ b/esp-hal/src/timer.rs
@@ -918,10 +918,12 @@ pub mod etm {
 
     impl Sealed for TimerEtmTask {}
 
+    /// General purpose timer ETM events
     pub trait TimerEtmEvents<TG> {
         fn on_alarm(&self) -> TimerEtmEvent;
     }
 
+    /// General purpose timer ETM tasks
     pub trait TimerEtmTasks<TG> {
         fn cnt_start(&self) -> TimerEtmTask;
         fn cnt_stop(&self) -> TimerEtmTask;
@@ -934,6 +936,7 @@ pub mod etm {
     where
         TG: TimerGroupInstance,
     {
+        /// ETM event triggered on alarm
         fn on_alarm(&self) -> TimerEtmEvent {
             TimerEtmEvent { id: 48 + TG::id() }
         }
@@ -943,21 +946,28 @@ pub mod etm {
     where
         TG: TimerGroupInstance,
     {
+        /// ETM task to start the counter
         fn cnt_start(&self) -> TimerEtmTask {
             TimerEtmTask { id: 88 + TG::id() }
         }
 
+        /// ETM task to start the alarm
         fn alarm_start(&self) -> TimerEtmTask {
             TimerEtmTask { id: 90 + TG::id() }
         }
 
+        /// ETM task to stop the counter
         fn cnt_stop(&self) -> TimerEtmTask {
             TimerEtmTask { id: 92 + TG::id() }
         }
 
+        /// ETM task to reload the counter
         fn cnt_reload(&self) -> TimerEtmTask {
             TimerEtmTask { id: 94 + TG::id() }
         }
+
+        /// ETM task to load the counter with the value stored when the last
+        /// `now()` was called
         fn cnt_cap(&self) -> TimerEtmTask {
             TimerEtmTask { id: 96 + TG::id() }
         }