[nrf fromlist] drivers: clock_control: nrf54h-fll16m: use values from BICR

The real, applicable and trusted values are the ones flashed into BICR.
So, drop DT properties that replicate BICR and use runtime reads to BICR
instead.

Upstream PR #: 81122

Signed-off-by: Gerard Marull-Paretas <[email protected]>
(cherry picked from commit a41e7e407448e731cdb3861864d89b1632b57b3d)

Author: gmarull

drivers/clock_control/clock_control_nrf2_fll16m.c

@@ -8,7 +8,9 @@
 #include "clock_control_nrf2_common.h"
 #include <zephyr/devicetree.h>
 #include <zephyr/drivers/clock_control/nrf_clock_control.h>
+
 #include <soc_lrcconf.h>
+#include <hal/nrf_bicr.h>
 
 #include <zephyr/logging/log.h>
 LOG_MODULE_DECLARE(clock_control_nrf2, CONFIG_CLOCK_CONTROL_LOG_LEVEL);
@@ -23,26 +25,17 @@ BUILD_ASSERT(DT_NUM_INST_STATUS_OKAY(DT_DRV_COMPAT) == 1,
 #define FLL16M_MODE_BYPASS      2
 #define FLL16M_MODE_DEFAULT     FLL16M_MODE_OPEN_LOOP
 
-#define FLL16M_LFXO_NODE DT_INST_PHANDLE_BY_NAME(0, clocks, lfxo)
 #define FLL16M_HFXO_NODE DT_INST_PHANDLE_BY_NAME(0, clocks, hfxo)
 
-#define FLL16M_HAS_LFXO DT_NODE_HAS_STATUS_OKAY(FLL16M_LFXO_NODE)
-
-#define FLL16M_LFXO_ACCURACY DT_PROP(FLL16M_LFXO_NODE, accuracy_ppm)
 #define FLL16M_HFXO_ACCURACY DT_PROP(FLL16M_HFXO_NODE, accuracy_ppm)
 #define FLL16M_OPEN_LOOP_ACCURACY DT_INST_PROP(0, open_loop_accuracy_ppm)
 #define FLL16M_CLOSED_LOOP_BASE_ACCURACY DT_INST_PROP(0, closed_loop_base_accuracy_ppm)
 #define FLL16M_MAX_ACCURACY FLL16M_HFXO_ACCURACY
 
-/* Closed-loop mode uses LFXO as source if present, HFXO otherwise */
-#if FLL16M_HAS_LFXO
-#define FLL16M_CLOSED_LOOP_ACCURACY (FLL16M_CLOSED_LOOP_BASE_ACCURACY + FLL16M_LFXO_ACCURACY)
-#else
-#define FLL16M_CLOSED_LOOP_ACCURACY (FLL16M_CLOSED_LOOP_BASE_ACCURACY + FLL16M_HFXO_ACCURACY)
-#endif
+#define BICR (NRF_BICR_Type *)DT_REG_ADDR(DT_NODELABEL(bicr))
 
 /* Clock options sorted from lowest to highest accuracy */
-static const struct clock_options {
+static struct clock_options {
 	uint16_t accuracy;
 	uint8_t mode;
 } clock_options[] = {
@@ -51,7 +44,6 @@ static const struct clock_options {
 		.mode = FLL16M_MODE_OPEN_LOOP,
 	},
 	{
-		.accuracy = FLL16M_CLOSED_LOOP_ACCURACY,
 		.mode = FLL16M_MODE_CLOSED_LOOP,
 	},
 	{
@@ -233,6 +225,27 @@ static int api_get_rate_fll16m(const struct device *dev,
 static int fll16m_init(const struct device *dev)
 {
 	struct fll16m_dev_data *dev_data = dev->data;
+	nrf_bicr_lfosc_mode_t lfosc_mode;
+
+	clock_options[1].accuracy = FLL16M_CLOSED_LOOP_BASE_ACCURACY;
+
+	/* Closed-loop mode uses LFXO as source if present, HFXO otherwise */
+	lfosc_mode = nrf_bicr_lfosc_mode_get(BICR);
+
+	if (lfosc_mode != NRF_BICR_LFOSC_MODE_UNCONFIGURED &&
+	    lfosc_mode != NRF_BICR_LFOSC_MODE_DISABLED) {
+		int ret;
+		uint16_t accuracy;
+
+		ret = lfosc_get_accuracy(&accuracy);
+		if (ret < 0) {
+			return ret;
+		}
+
+		clock_options[1].accuracy += accuracy;
+	} else {
+		clock_options[1].accuracy += FLL16M_HFXO_ACCURACY;
+	}
 
 	return clock_config_init(&dev_data->clk_cfg,
 				 ARRAY_SIZE(dev_data->clk_cfg.onoff),