From 368f3eb88d7c40b185a2974d5bd871d2c1d7df87 Mon Sep 17 00:00:00 2001
From: Piotr Pryga <piotr.pryga@nordicsemi.no>
Date: Thu, 28 Nov 2024 22:28:19 +0100
Subject: [PATCH] mpsl: clock_ctrl: Add integration layer for nRF54H20

Add integration layer for MPSL external clock driver and nrf2 clock
control for nRF5420. This is mandatory for the nRF54H20.

Note: The nrf2 clock control requires the MPSL initialization
to be done later. The nrf2 clock control depends on nRFS that
is initialized at POST_KENREL init level. Its init priority is
CONFIG_NRFS_BACKEND_IPC_SERVICE_INIT_PRIO that is lower than former
MPSL init level. To make sure the mpsl lfclk request and response
is handled corrently we must make the MPSL is initialized after it.

Signed-off-by: Piotr Pryga <piotr.pryga@nordicsemi.no>
---
 subsys/mpsl/clock_ctrl/mpsl_clock_ctrl.c | 103 +++++++++++++++++++++++
 1 file changed, 103 insertions(+)

diff --git a/subsys/mpsl/clock_ctrl/mpsl_clock_ctrl.c b/subsys/mpsl/clock_ctrl/mpsl_clock_ctrl.c
index 3107e10755e3..f0eaf4b6d992 100644
--- a/subsys/mpsl/clock_ctrl/mpsl_clock_ctrl.c
+++ b/subsys/mpsl/clock_ctrl/mpsl_clock_ctrl.c
@@ -31,7 +31,11 @@ static struct clock_onoff_state m_lfclk_state;
 
 static int32_t m_lfclk_release(void);
 
+#if defined(CONFIG_CLOCK_CONTROL_NRF2_NRFS_CLOCK_TIMEOUT_MS)
+#define MPSL_LFCLK_REQUEST_WAIT_TIMEOUT_MS CONFIG_CLOCK_CONTROL_NRF2_NRFS_CLOCK_TIMEOUT_MS
+#else
 #define MPSL_LFCLK_REQUEST_WAIT_TIMEOUT_MS 1000
+#endif /* CONFIG_CLOCK_CONTROL_NRF2_NRFS_CLOCK_TIMEOUT_MS */
 
 /** @brief LFCLK request callback.
  *
@@ -197,6 +201,105 @@ static bool m_hfclk_is_running(void)
 	return false;
 }
 
+#elif defined(CONFIG_CLOCK_CONTROL_NRF2)
+
+/* Temporary macro because there is no system level configuration of LFCLK source and its accuracy
+ * for nRF54H SoC series. What more, there is no API to retrieve the information about accuracy of
+ * available LFCLK.
+ */
+#define MPSL_LFCLK_ACCURACY_PPM 500
+
+static const struct nrf_clock_spec m_lfclk_specs = {
+	.frequency = 32768,
+	.accuracy = MPSL_LFCLK_ACCURACY_PPM,
+	/* This affects selected LFCLK source. It doesn't switch to higher accuracy but selects more
+	 * precise but current hungry lfclk source.
+	 */
+	.precision = NRF_CLOCK_CONTROL_PRECISION_DEFAULT,
+};
+
+static void m_lfclk_calibration_start(void)
+{
+	/* This function is not supported when CONFIG_CLOCK_CONTROL_NRF2 is set.
+	 * As of now MPSL does not use this API in this configuration.
+	 */
+	__ASSERT_NO_MSG(false);
+}
+
+static bool m_lfclk_calibration_is_enabled(void)
+{
+	/* This function should not be called from MPSL if CONFIG_CLOCK_CONTROL_NRF2 is set */
+	__ASSERT_NO_MSG(false);
+	return false;
+}
+
+static int32_t m_lfclk_request(void)
+{
+	const struct device *lfclk_dev = DEVICE_DT_GET(DT_NODELABEL(lfclk));
+	int err;
+
+	sys_notify_init_callback(&m_lfclk_state.cli.notify, lfclk_request_cb);
+	k_sem_init(&m_lfclk_state.sem, 0, 1);
+
+	err = nrf_clock_control_request(lfclk_dev, &m_lfclk_specs, &m_lfclk_state.cli);
+	if (err < 0) {
+		return err;
+	}
+
+	atomic_inc(&m_lfclk_state.m_clk_refcnt);
+
+	return 0;
+}
+
+static int32_t m_lfclk_release(void)
+{
+	const struct device *lfclk_dev = DEVICE_DT_GET(DT_NODELABEL(lfclk));
+	int err;
+
+	err = nrf_clock_control_cancel_or_release(lfclk_dev, &m_lfclk_specs, &m_lfclk_state.cli);
+	if (err < 0) {
+		return err;
+	}
+
+	atomic_dec(&m_lfclk_state.m_clk_refcnt);
+
+	return 0;
+}
+
+static void m_hfclk_request(void)
+{
+	if (atomic_inc(&m_hfclk_refcnt) > (atomic_val_t)0) {
+		return;
+	}
+
+	nrf_clock_control_hfxo_request();
+}
+
+static void m_hfclk_release(void)
+{
+	if (atomic_get(&m_hfclk_refcnt) < (atomic_val_t)1) {
+		return;
+	}
+
+	if (atomic_dec(&m_hfclk_refcnt) > (atomic_val_t)1) {
+		return;
+	}
+
+	nrf_clock_control_hfxo_release();
+}
+
+static bool m_hfclk_is_running(void)
+{
+	/* As of now assume the HFCLK is running after the request was put.
+	 * This puts the responsibility to the user to check if the time
+	 * since last request is larger than the HFXO rampup time.
+	 */
+	if (atomic_get(&m_hfclk_refcnt) < (atomic_val_t)1) {
+		return false;
+	}
+
+	return true;
+}
 #else
 #error "Unsupported clock control"
 #endif /* CONFIG_CLOCK_CONTROL_NRF */