drivers: timer: nrf_grtc: Add support for clock outputs

Add support for GRTC clock output pins.

Signed-off-by: Adam Kondraciuk <[email protected]>

Author: adamkondraciuk

drivers/timer/nrf_grtc_timer.c

@@ -10,12 +10,15 @@
 #if defined(CONFIG_CLOCK_CONTROL_NRF)
 #include <zephyr/drivers/clock_control/nrf_clock_control.h>
 #endif
+#include <zephyr/drivers/pinctrl.h>
 #include <zephyr/drivers/timer/system_timer.h>
 #include <zephyr/drivers/timer/nrf_grtc_timer.h>
 #include <nrfx_grtc.h>
 #include <zephyr/sys/math_extras.h>
 
 #define GRTC_NODE DT_NODELABEL(grtc)
+#define HFCLK_NODE DT_PHANDLE_BY_NAME(GRTC_NODE, clocks, hfclock)
+#define LFCLK_NODE DT_PHANDLE_BY_NAME(GRTC_NODE, clocks, lfclock)
 
 /* Ensure that GRTC properties in devicetree are defined correctly. */
 #if !DT_NODE_HAS_PROP(GRTC_NODE, owned_channels)
@@ -49,7 +52,7 @@
 
 #define MAX_CYCLES (MAX_TICKS * CYC_PER_TICK)
 
-#define LFCLK_FREQUENCY_HZ 32768
+#define LFCLK_FREQUENCY_HZ DT_PROP(LFCLK_NODE, clock_frequency)
 
 #if defined(CONFIG_TEST)
 const int32_t z_sys_timer_irq_for_test = DT_IRQN(GRTC_NODE);
@@ -518,7 +521,35 @@ static int sys_clock_driver_init(void)
 #if defined(CONFIG_NRF_GRTC_ALWAYS_ON)
 	nrfx_grtc_active_request_set(true);
 #endif
+
+#if DT_PROP(GRTC_NODE, clkout_32k)
+	nrfy_grtc_clkout_set(NRF_GRTC, NRF_GRTC_CLKOUT_32K, true);
+#endif
+
+#if DT_NODE_HAS_PROP(GRTC_NODE, clkout_fast_frequency_hz)
+#if !DT_NODE_HAS_PROP(HFCLK_NODE, clock_frequency)
+#error "hfclock reference required when fast clock output is enabled."
+#endif
+
+#if DT_PROP(GRTC_NODE, clkout_fast_frequency_hz) > (DT_PROP(HFCLK_NODE, clock_frequency) / 2)
+#error "Invalid frequency value for fast clock output."
+#endif
+	uint32_t base_frequency = DT_PROP(HFCLK_NODE, clock_frequency);
+	uint32_t requested_frequency = DT_PROP(GRTC_NODE, clkout_fast_frequency_hz);
+	uint32_t grtc_div = base_frequency / (requested_frequency * 2);
+
+	nrfy_grtc_clkout_divider_set(NRF_GRTC, (uint8_t)grtc_div);
+	nrfy_grtc_clkout_set(NRF_GRTC, NRF_GRTC_CLKOUT_FAST, true);
+#endif
+
+#if DT_PROP(GRTC_NODE, clkout_32k) || DT_NODE_HAS_PROP(GRTC_NODE, clkout_fast_frequency_hz)
+	PINCTRL_DT_DEFINE(GRTC_NODE);
+	const struct pinctrl_dev_config *pcfg = PINCTRL_DT_DEV_CONFIG_GET(GRTC_NODE);
+
+	return pinctrl_apply_state(pcfg, PINCTRL_STATE_DEFAULT);
+#else
 	return 0;
+#endif
 }
 
 void sys_clock_set_timeout(int32_t ticks, bool idle)