From 660fc4f7602c0be689e2c6cb4b20e55a26127636 Mon Sep 17 00:00:00 2001
From: Ulf Lilleengen <ulf@digili.no>
Date: Wed, 26 Nov 2025 14:35:18 +0100
Subject: feat: support nrf54 GRTC as time-driver

* Refactor GRTC peripheral splitting it into multiple channels
* Reserve channel 1 for time-driver if enabled
* Implement time-driver using GRTC (RTC peripheral is now removed).
* Add timer example to nrf54l15
---
 examples/nrf54l15/Cargo.toml       |  2 +-
 examples/nrf54l15/src/bin/rtc.rs   | 56 --------------------------------------
 examples/nrf54l15/src/bin/timer.rs | 30 ++++++++++++++++++++
 3 files changed, 31 insertions(+), 57 deletions(-)
 delete mode 100644 examples/nrf54l15/src/bin/rtc.rs
 create mode 100644 examples/nrf54l15/src/bin/timer.rs

(limited to 'examples')

diff --git a/examples/nrf54l15/Cargo.toml b/examples/nrf54l15/Cargo.toml
index 4ef77279f..f34df0f26 100644
--- a/examples/nrf54l15/Cargo.toml
+++ b/examples/nrf54l15/Cargo.toml
@@ -10,7 +10,7 @@ embassy-futures = { version = "0.1.2", path = "../../embassy-futures" }
 embassy-executor = { version = "0.9.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "executor-interrupt", "defmt"] }
 embassy-time = { version = "0.5.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime"] }
 embassy-sync = { version = "0.7.2", path = "../../embassy-sync", features = ["defmt"] }
-embassy-nrf = { version = "0.8.0", path = "../../embassy-nrf", features = ["defmt", "nrf54l15-app-s", "time-driver-rtc1", "gpiote", "unstable-pac", "time"] }
+embassy-nrf = { version = "0.8.0", path = "../../embassy-nrf", features = ["defmt", "nrf54l15-app-s", "time-driver-grtc", "gpiote", "unstable-pac", "time"] }
 embedded-io = { version = "0.6.0", features = ["defmt-03"]  }
 embedded-io-async = { version = "0.6.1", features = ["defmt-03"] }
 
diff --git a/examples/nrf54l15/src/bin/rtc.rs b/examples/nrf54l15/src/bin/rtc.rs
deleted file mode 100644
index a45aaca52..000000000
--- a/examples/nrf54l15/src/bin/rtc.rs
+++ /dev/null
@@ -1,56 +0,0 @@
-#![no_std]
-#![no_main]
-
-use core::cell::RefCell;
-
-use embassy_executor::Spawner;
-use embassy_nrf::gpio::{Level, Output, OutputDrive};
-use embassy_nrf::interrupt;
-use embassy_nrf::rtc::Rtc;
-use embassy_sync::blocking_mutex::Mutex;
-use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
-use portable_atomic::AtomicU64;
-use {defmt_rtt as _, panic_probe as _};
-
-// 64 bit counter which will never overflow.
-static TICK_COUNTER: AtomicU64 = AtomicU64::new(0);
-static RTC: Mutex<CriticalSectionRawMutex, RefCell<Option<Rtc<'static>>>> = Mutex::new(RefCell::new(None));
-
-#[embassy_executor::main]
-async fn main(_spawner: Spawner) {
-    defmt::println!("nRF54L15 RTC example");
-    let p = embassy_nrf::init(Default::default());
-    let mut led = Output::new(p.P2_09, Level::High, OutputDrive::Standard);
-    // Counter resolution is 125 ms.
-    let mut rtc = Rtc::new(p.RTC10, (1 << 12) - 1).unwrap();
-    rtc.enable_interrupt(embassy_nrf::rtc::Interrupt::Tick, true);
-    rtc.enable_event(embassy_nrf::rtc::Interrupt::Tick);
-    rtc.enable();
-    RTC.lock(|r| {
-        let mut rtc_borrow = r.borrow_mut();
-        *rtc_borrow = Some(rtc);
-    });
-
-    let mut last_counter_val = 0;
-    loop {
-        let current = TICK_COUNTER.load(core::sync::atomic::Ordering::Relaxed);
-        if current != last_counter_val {
-            led.toggle();
-            last_counter_val = current;
-        }
-    }
-}
-
-#[interrupt]
-fn RTC10() {
-    // For 64-bit, we do not need to worry about overflowing, at least not for realistic program
-    // lifetimes.
-    TICK_COUNTER.fetch_add(1, core::sync::atomic::Ordering::Relaxed);
-    RTC.lock(|r| {
-        let mut rtc_borrow = r.borrow_mut();
-        rtc_borrow
-            .as_mut()
-            .unwrap()
-            .reset_event(embassy_nrf::rtc::Interrupt::Tick);
-    });
-}
diff --git a/examples/nrf54l15/src/bin/timer.rs b/examples/nrf54l15/src/bin/timer.rs
new file mode 100644
index 000000000..68acc91c1
--- /dev/null
+++ b/examples/nrf54l15/src/bin/timer.rs
@@ -0,0 +1,30 @@
+#![no_std]
+#![no_main]
+
+use defmt::{info, unwrap};
+use embassy_executor::Spawner;
+use embassy_time::Timer;
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::task]
+async fn run1() {
+    loop {
+        info!("BIG INFREQUENT TICK");
+        Timer::after_secs(10).await;
+    }
+}
+
+#[embassy_executor::task]
+async fn run2() {
+    loop {
+        info!("tick");
+        Timer::after_secs(1).await;
+    }
+}
+
+#[embassy_executor::main]
+async fn main(spawner: Spawner) {
+    let _p = embassy_nrf::init(Default::default());
+    spawner.spawn(unwrap!(run1()));
+    spawner.spawn(unwrap!(run2()));
+}
-- 
cgit