drivers: grtc timer added support for system off for nrf54h20

Added option to use system channel for setup wakeup from soft off.
In Lilium there is insuficcient grtc channels and no spare channel
that can be used as wake up source. Added function to disable all
grtc channels, except the one used for wake up to be able to enter
soft off stated on local domain (disable uncexpected grtc wake ups).

Signed-off-by: Łukasz Stępnicki <[email protected]>

Author: lstnl

drivers/timer/Kconfig.nrf_grtc

@@ -56,4 +56,11 @@ config NRF_GRTC_TIMER_AUTO_KEEP_ALIVE
 	  This feature prevents the SYSCOUNTER from sleeping when any core is in
 	  active state.
 
+config NRF_GRTC_TIMER_USE_SYSTEM_CHANNEL_TO_WAKEUP_FROM_SYSTEMOFF
+	bool
+	depends on POWEROFF
+	default y if SOC_NRF54H20
+	help
+	  Use system channel to schedule wake up time.
+
 endif # NRF_GRTC_TIMER

drivers/timer/nrf_grtc_timer.c

@@ -365,17 +365,40 @@ uint64_t z_nrf_grtc_timer_startup_value_get(void)
 }
 
 #if defined(CONFIG_POWEROFF)
-#if defined(CONFIG_NRF_GRTC_START_SYSCOUNTER)
+static int32_t wakeup_channel = -1;
+
+int32_t z_nrf_grtc_timer_wakeup_channel_get(void)
+{
+	return wakeup_channel;
+}
+
+void z_nrf_grtc_timer_disable_owned_cc_channels(int32_t reserved_channel)
+{
+	uint32_t chan;
+
+	k_spinlock_key_t key = k_spin_lock(&lock);
+
+	for (uint32_t grtc_chan_mask = NRFX_GRTC_CONFIG_ALLOWED_CC_CHANNELS_MASK;
+	     grtc_chan_mask > 0; grtc_chan_mask &= ~BIT(chan)) {
+		/* Clear all GRTC channels except the reserved_channel. */
+		chan = u32_count_trailing_zeros(grtc_chan_mask);
+		if (chan != reserved_channel) {
+			nrfx_grtc_syscounter_cc_disable(chan);
+		}
+	}
+	k_spin_unlock(&lock, key);
+}
+
 int z_nrf_grtc_wakeup_prepare(uint64_t wake_time_us)
 {
-	nrfx_err_t err_code;
 	static uint8_t systemoff_channel;
 	uint64_t now = counter();
-	nrfx_grtc_sleep_config_t sleep_cfg;
+	int ret;
 	/* Minimum time that ensures valid execution of system-off procedure. */
 	uint32_t minimum_latency_us;
-	uint32_t chan;
-	int ret;
+
+#if CONFIG_NRF_GRTC_START_SYSCOUNTER
+	nrfx_grtc_sleep_config_t sleep_cfg;
 
 	nrfx_grtc_sleep_configuration_get(&sleep_cfg);
 	minimum_latency_us = (sleep_cfg.waketime + sleep_cfg.timeout) *
@@ -384,34 +407,34 @@ int z_nrf_grtc_wakeup_prepare(uint64_t wake_time_us)
 	sleep_cfg.auto_mode = false;
 	nrfx_grtc_sleep_configure(&sleep_cfg);
 
+#else
+	minimum_latency_us = CONFIG_NRF_GRTC_SYSCOUNTER_SLEEP_MINIMUM_LATENCY;
+#endif
 	if (minimum_latency_us > wake_time_us) {
 		return -EINVAL;
 	}
 
 	k_spinlock_key_t key = k_spin_lock(&lock);
 
-	err_code = nrfx_grtc_channel_alloc(&systemoff_channel);
+#if CONFIG_NRF_GRTC_TIMER_USE_SYSTEM_CHANNEL_TO_WAKEUP_FROM_SYSTEMOFF
+	systemoff_channel = system_clock_channel_data.channel;
+#else
+	nrfx_err_t err_code = nrfx_grtc_channel_alloc(&systemoff_channel);
 	if (err_code != NRFX_SUCCESS) {
 		k_spin_unlock(&lock, key);
 		return -ENOMEM;
 	}
-	(void)nrfx_grtc_syscounter_cc_int_disable(systemoff_channel);
-	ret = compare_set(systemoff_channel,
-			  now + wake_time_us * sys_clock_hw_cycles_per_sec() / USEC_PER_SEC, NULL,
-			  NULL);
+#endif
+	(void) nrfx_grtc_syscounter_cc_int_disable(systemoff_channel);
+	int64_t delay = now + wake_time_us * sys_clock_hw_cycles_per_sec() / USEC_PER_SEC;
+
+	ret = compare_set(systemoff_channel, delay, NULL, NULL);
 	if (ret < 0) {
 		k_spin_unlock(&lock, key);
 		return ret;
 	}
 
-	for (uint32_t grtc_chan_mask = NRFX_GRTC_CONFIG_ALLOWED_CC_CHANNELS_MASK;
-	     grtc_chan_mask > 0; grtc_chan_mask &= ~BIT(chan)) {
-		/* Clear all GRTC channels except the systemoff_channel. */
-		chan = u32_count_trailing_zeros(grtc_chan_mask);
-		if (chan != systemoff_channel) {
-			nrfx_grtc_syscounter_cc_disable(chan);
-		}
-	}
+	z_nrf_grtc_timer_disable_owned_cc_channels(systemoff_channel);
 
 	/* Make sure that wake_time_us was not triggered yet. */
 	if (nrfx_grtc_syscounter_compare_event_check(systemoff_channel)) {
@@ -420,98 +443,21 @@ int z_nrf_grtc_wakeup_prepare(uint64_t wake_time_us)
 	}
 
 	/* This mechanism ensures that stored CC value is latched. */
+#if CONFIG_NRF_GRTC_START_SYSCOUNTER
 	uint32_t wait_time =
 		nrfy_grtc_timeout_get(NRF_GRTC) * CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC / 32768 +
 		MAX_CC_LATCH_WAIT_TIME_US;
-	k_busy_wait(wait_time);
-	k_spin_unlock(&lock, key);
-	return 0;
-}
 #else
-int z_nrf_grtc_wakeup_prepare(uint64_t wake_time_us)
-{
-	//nrfx_err_t err_code;
-	//static uint8_t systemoff_channel;
-	//uint64_t now = counter();
-	//nrfx_grtc_sleep_config_t sleep_cfg;
-	/* Minimum time that ensures valid execution of system-off procedure. */
-	//uint32_t minimum_latency_us;
-	uint32_t chan;
-	//int ret;
-
-	// nrfx_grtc_sleep_configuration_get(&sleep_cfg);
-	// minimum_latency_us =
-	// 	(sleep_cfg.waketime + sleep_cfg.timeout) * USEC_PER_SEC / LFCLK_FREQUENCY_HZ +
-	// 	CONFIG_NRF_GRTC_SYSCOUNTER_SLEEP_MINIMUM_LATENCY;
-	// sleep_cfg.auto_mode = false;
-	// nrfx_grtc_sleep_configure(&sleep_cfg);
-
-	// if (minimum_latency_us > wake_time_us) {
-	// 	return -EINVAL;
-	// }
-
-	//k_spinlock_key_t key = k_spin_lock(&lock);
-
-	// err_code = nrfx_grtc_channel_alloc(&systemoff_channel);
-	// if (err_code != NRFX_SUCCESS) {
-	// 	k_spin_unlock(&lock, key);
-	// 	return -ENOMEM;
-	// }
-	//(void)nrfx_grtc_syscounter_cc_int_disable(systemoff_channel);
-	// ret = compare_set(systemoff_channel,
-	// 		  now + wake_time_us * sys_clock_hw_cycles_per_sec() / USEC_PER_SEC, NULL,
-	// 		  NULL);
-	// if (ret < 0) {
-	// 	k_spin_unlock(&lock, key);
-	// 	return ret;
-	// }
-	// for (uint32_t grtc_chan_mask = NRFX_GRTC_CONFIG_ALLOWED_CC_CHANNELS_MASK;
-	for (uint32_t grtc_chan_mask = NRFX_GRTC_CONFIG_ALLOWED_CC_CHANNELS_MASK;
-	     grtc_chan_mask > 0; grtc_chan_mask &= ~BIT(chan)) {
-		/* Clear all GRTC channels except the systemoff_channel. */
-		chan = u32_count_trailing_zeros(grtc_chan_mask);
-		// if (chan != systemoff_channel) {
-		nrfx_grtc_syscounter_cc_disable(chan);
-		//}
-	}
-#if 0
-#if defined(CONFIG_SOC_NRF54H20_CPUAPP)
-	for (uint32_t grtc_chan_mask = 0x70;
-	     grtc_chan_mask > 0; grtc_chan_mask &= ~BIT(chan)) {
-		/* Clear all GRTC channels except the systemoff_channel. */
-		chan = u32_count_trailing_zeros(grtc_chan_mask);
-		// if (chan != systemoff_channel) {
-			nrfx_grtc_syscounter_cc_disable(chan);
-		// }
-	}
-#endif
-#if defined(CONFIG_SOC_NRF54H20_CPURAD)
-	//for (uint32_t grtc_chan_mask = NRFX_GRTC_CONFIG_ALLOWED_CC_CHANNELS_MASK;
-	for (uint32_t grtc_chan_mask = 0xFF80;
-	     grtc_chan_mask > 0; grtc_chan_mask &= ~BIT(chan)) {
-		/* Clear all GRTC channels except the systemoff_channel. */
-		chan = u32_count_trailing_zeros(grtc_chan_mask);
-		//if (chan != systemoff_channel) {
-			nrfx_grtc_syscounter_cc_disable(chan);
-		//}
-	}
+	uint32_t wait_time = MAX_CC_LATCH_WAIT_TIME_US;
 #endif
-#endif
-	// /* Make sure that wake_time_us was not triggered yet. */
-	// if (nrfx_grtc_syscounter_compare_event_check(systemoff_channel)) {
-	// 	k_spin_unlock(&lock, key);
-	// 	return -EINVAL;
-	// }
-
-	// /* This mechanism ensures that stored CC value is latched. */
-	//uint32_t wait_time =
-	//	nrfy_grtc_timeout_get(NRF_GRTC) * CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC / 32768 +
-	//	MAX_CC_LATCH_WAIT_TIME_US;
-	k_busy_wait(1000);
-	// k_spin_unlock(&lock, key);
+	/* Wait until the CC value is latched. */
+	k_busy_wait(wait_time);
+	k_spin_unlock(&lock, key);
+
+	wakeup_channel = systemoff_channel;
+
 	return 0;
 }
-#endif /* CONFIG_NRF_GRTC_START_SYSCOUNTER */
 #endif /* CONFIG_POWEROFF */
 
 uint32_t sys_clock_cycle_get_32(void)

include/zephyr/drivers/timer/nrf_grtc_timer.h

@@ -175,6 +175,24 @@ int z_nrf_grtc_timer_capture_prepare(int32_t chan);
  */
 int z_nrf_grtc_timer_capture_read(int32_t chan, uint64_t *captured_time);
 
+/** @brief Get the channel used for wakeup from system-off.
+ *
+ * @return Channel ID or -1 if no channel is reserved for that purpose.
+ */
+int32_t z_nrf_grtc_timer_wakeup_channel_get(void);
+
+/** @brief Disable all owned compare channels except the one specified.
+ *
+ * This function is used when preparing the system to enter system-off mode.
+ * It disables all compare channels owned by the driver except the one
+ * specified by @p reserved_channel. The reserved channel is typically used
+ * for wake-up from system-off.
+ * @param reserved_channel Channel ID to remain enabled.
+ *
+ * @note Set @p reserved_channel to -1 to disable all owned channels.
+ */
+void z_nrf_grtc_timer_disable_owned_cc_channels(int32_t reserved_channel);
+
 /** @brief Prepare GRTC as a source of wake up event and set the wake up time.
  *
  * @note Calling this function should be immediately followed by low-power mode enter

soc/nordic/nrf54h/power.c

@@ -8,6 +8,7 @@
 #include <zephyr/toolchain.h>
 #include <zephyr/pm/policy.h>
 #include <zephyr/arch/common/pm_s2ram.h>
+#include <zephyr/drivers/timer/nrf_grtc_timer.h>
 #include <hal/nrf_resetinfo.h>
 #include <hal/nrf_memconf.h>
 #include <zephyr/cache.h>
@@ -82,6 +83,10 @@ void nrf_poweroff(void)
 #endif
 	common_suspend();
 
+	/* Disable all owned compare channels except the one used for wakeup from system-off. */
+	z_nrf_grtc_timer_disable_owned_cc_channels(z_nrf_grtc_timer_wakeup_channel_get());
+
+	/* Indicate that we are ready for system off. */
 	nrf_lrcconf_task_trigger(NRF_LRCCONF010, NRF_LRCCONF_TASK_SYSTEMOFFREADY);
 
 	__set_BASEPRI(0);