drivers: timer: Enable STM32WB0_RADIO_TIMER Kconfig parameter

Use radio timer as the system timer when Bluetooth is used.

Modify CMakeLists.txt to compile radio timer driver when
STM32WB0_RADIO_TIMER is enabled.

Remove the common parts from hci_stm32wb0.c that are present
in the radio timer driver.

Set and retrieve the appropriate value for SYS_CLOCK_TICKS_PER_SEC and
SYS_CLOCK_HW_CYCLES_PER_SEC respectively.

Define radio_timer node and its properties.

Enable radio_timer node in nucleo_wb0x boards.

Signed-off-by: Ali Hozhabri <[email protected]>

Author: HoZHel

boards/st/nucleo_wb05kz/nucleo_wb05kz.dts

@@ -133,6 +133,10 @@
 	status = "okay";
 };
 
+&radio_timer {
+	status = "okay";
+};
+
 &usart1 {
 	pinctrl-0 = <&usart1_tx_pa1 &usart1_rx_pb0>;
 	pinctrl-names = "default";

boards/st/nucleo_wb07cc/nucleo_wb07cc.dts

@@ -132,6 +132,10 @@
 	status = "okay";
 };
 
+&radio_timer {
+	status = "okay";
+};
+
 &usart1 {
 	pinctrl-0 = <&usart1_tx_pa9 &usart1_rx_pa8>;
 	pinctrl-names = "default";

boards/st/nucleo_wb09ke/nucleo_wb09ke.dts

@@ -133,6 +133,10 @@
 	status = "okay";
 };
 
+&radio_timer {
+	status = "okay";
+};
+
 &usart1 {
 	pinctrl-0 = <&usart1_tx_pa1 &usart1_rx_pb0>;
 	pinctrl-names = "default";

drivers/bluetooth/hci/hci_stm32wb0.c

@@ -30,16 +30,8 @@ LOG_MODULE_REGISTER(bt_driver);
 
 #define DT_DRV_COMPAT st_hci_stm32wb0
 
-/* Max HS startup time expressed in system time (1953 us / 2.4414 us) */
-#define MAX_HS_STARTUP_TIME 320
-#define BLE_WKUP_PRIO       0
-#define BLE_WKUP_FLAGS      0
 #define BLE_TX_RX_PRIO      0
 #define BLE_TX_RX_FLAGS     0
-#define CPU_WKUP_PRIO       1
-#define CPU_WKUP_FLAGS      0
-#define BLE_ERROR_PRIO      3
-#define BLE_ERROR_FLAGS     0
 #define BLE_RXTX_SEQ_PRIO   3
 #define BLE_RXTX_SEQ_FLAGS  0
 #define PKA_PRIO	    2
@@ -58,7 +50,7 @@ LOG_MODULE_REGISTER(bt_driver);
 
 static uint32_t __noinit dyn_alloc_a[BLE_DYN_ALLOC_SIZE >> 2];
 static uint8_t buffer_out_mem[MAX_EVENT_SIZE];
-static struct k_work_delayable hal_radio_timer_work, ble_stack_work;
+static struct k_work_delayable ble_stack_work;
 
 static struct net_buf *get_rx(uint8_t *msg);
 static PKA_HandleTypeDef hpka;
@@ -77,6 +69,14 @@ int BLEPLAT_NvmGet(void)
 	return 0;
 }
 
+uint8_t BLEPLAT_SetRadioTimerValue(uint32_t Time, uint8_t EventType, uint8_t CalReq)
+{
+	uint8_t retval;
+
+	retval = HAL_RADIO_TIMER_SetRadioTimerValue(Time, EventType, CalReq);
+	return retval;
+}
+
 static void blestack_process(struct k_work *work)
 {
 	BLE_STACK_Tick();
@@ -85,11 +85,6 @@ static void blestack_process(struct k_work *work)
 	}
 }
 
-static void vtimer_process(struct k_work *work)
-{
-	HAL_RADIO_TIMER_Tick();
-}
-
 /* "If, since the last power-on or reset, the Host has ever issued a legacy
  * advertising command and then issues an extended advertising command, or
  * has ever issued an extended advertising command and then issues a legacy
@@ -210,28 +205,13 @@ void send_event(uint8_t *buffer_out, uint16_t buffer_out_length, int8_t overflow
 
 void HAL_RADIO_TIMER_TxRxWakeUpCallback(void)
 {
-	k_work_schedule(&hal_radio_timer_work, K_NO_WAIT);
-	k_work_schedule(&ble_stack_work, K_NO_WAIT);
-}
-
-void HAL_RADIO_TIMER_CpuWakeUpCallback(void)
-{
-	k_work_schedule(&hal_radio_timer_work, K_NO_WAIT);
 	k_work_schedule(&ble_stack_work, K_NO_WAIT);
 }
 
 void HAL_RADIO_TxRxCallback(uint32_t flags)
 {
 	BLE_STACK_RadioHandler(flags);
 	k_work_schedule(&ble_stack_work, K_NO_WAIT);
-	k_work_schedule(&hal_radio_timer_work, K_NO_WAIT);
-}
-
-ISR_DIRECT_DECLARE(RADIO_TIMER_TXRX_WKUP_IRQHandler)
-{
-	HAL_RADIO_TIMER_TXRX_WKUP_IRQHandler();
-	ISR_DIRECT_PM(); /* PM done after servicing interrupt for best latency */
-	return 1;
 }
 
 ISR_DIRECT_DECLARE(RADIO_TXRX_IRQHandler)
@@ -248,56 +228,24 @@ ISR_DIRECT_DECLARE(RADIO_TXRX_SEQ_IRQHandler)
 	return 1;
 }
 
-ISR_DIRECT_DECLARE(RADIO_TIMER_CPU_WKUP_IRQHandler)
-{
-	HAL_RADIO_TIMER_TimeoutCallback();
-	HAL_RADIO_TIMER_CpuWakeUpCallback();
-	ISR_DIRECT_PM(); /* PM done after servicing interrupt for best latency */
-	return 1;
-}
-
-ISR_DIRECT_DECLARE(RADIO_TIMER_ERROR_IRQHandler)
-{
-	volatile uint32_t debug_cmd;
-
-	BLUE->DEBUGCMDREG |= 1;
-	/* If the device is configured with CLK_SYS = 64MHz
-	 * and BLE clock = 16MHz, a register read is necessary
-	 * to ensure interrupt register is properly cleared
-	 * due to AHB down converter latency
-	 */
-	debug_cmd = BLUE->DEBUGCMDREG;
-	LOG_ERR("Timer error");
-	ISR_DIRECT_PM(); /* PM done after servicing interrupt for best latency */
-	return 1;
-}
-
 /* Function called from PKA_IRQHandler() context. */
 void PKAMGR_IRQCallback(void)
 {
 	k_work_schedule(&ble_stack_work, K_NO_WAIT);
 }
 
-static int _PKA_IRQHandler(void *args)
+static void _PKA_IRQHandler(void *args)
 {
 	ARG_UNUSED(args);
 
 	HAL_PKA_IRQHandler(&hpka);
-	ISR_DIRECT_PM(); /* PM done after servicing interrupt for best latency */
-	return 1;
 }
 
 static void ble_isr_installer(void)
 {
-	IRQ_DIRECT_CONNECT(RADIO_TIMER_TXRX_WKUP_IRQn, BLE_WKUP_PRIO,
-			   RADIO_TIMER_TXRX_WKUP_IRQHandler, BLE_WKUP_FLAGS);
 	IRQ_DIRECT_CONNECT(RADIO_TXRX_IRQn, BLE_TX_RX_PRIO, RADIO_TXRX_IRQHandler, BLE_TX_RX_FLAGS);
-	IRQ_DIRECT_CONNECT(RADIO_TIMER_CPU_WKUP_IRQn, CPU_WKUP_PRIO,
-			   RADIO_TIMER_CPU_WKUP_IRQHandler, CPU_WKUP_FLAGS);
 	IRQ_DIRECT_CONNECT(RADIO_TXRX_SEQ_IRQn, BLE_RXTX_SEQ_PRIO, RADIO_TXRX_SEQ_IRQHandler,
 			   BLE_RXTX_SEQ_FLAGS);
-	IRQ_DIRECT_CONNECT(RADIO_TIMER_ERROR_IRQn, BLE_ERROR_PRIO, RADIO_TIMER_ERROR_IRQHandler,
-			   BLE_ERROR_FLAGS);
 	IRQ_CONNECT(PKA_IRQn, PKA_PRIO, _PKA_IRQHandler, NULL, PKA_FLAGS);
 }
 
@@ -449,7 +397,6 @@ static int bt_hci_stm32wb0_send(const struct device *dev, struct net_buf *buf)
 static int bt_hci_stm32wb0_open(const struct device *dev, bt_hci_recv_t recv)
 {
 	struct hci_data *data = dev->data;
-	RADIO_TIMER_InitTypeDef VTIMER_InitStruct = {MAX_HS_STARTUP_TIME, 0, 0};
 	RADIO_HandleTypeDef hradio = {0};
 	BLE_STACK_InitTypeDef BLE_STACK_InitParams = {
 		.BLEStartRamAddress = (uint8_t *)dyn_alloc_a,
@@ -486,8 +433,6 @@ static int bt_hci_stm32wb0_open(const struct device *dev, bt_hci_recv_t recv)
 	ble_isr_installer();
 	hradio.Instance = RADIO;
 	HAL_RADIO_Init(&hradio);
-	HAL_RADIO_TIMER_Init(&VTIMER_InitStruct);
-
 	HW_AES_Init();
 	hpka.Instance = PKA;
 	HAL_PKA_Init(&hpka);
@@ -504,7 +449,6 @@ static int bt_hci_stm32wb0_open(const struct device *dev, bt_hci_recv_t recv)
 	aci_adv_nwk_init();
 
 	data->recv = recv;
-	k_work_init_delayable(&hal_radio_timer_work, vtimer_process);
 	k_work_init_delayable(&ble_stack_work, blestack_process);
 	k_work_schedule(&ble_stack_work, K_NO_WAIT);
 

drivers/timer/CMakeLists.txt

@@ -40,6 +40,7 @@ zephyr_library_sources_ifdef(CONFIG_REALTEK_RTS5912_RTMR realtek_rts5912_rtmr.c)
 zephyr_library_sources_ifdef(CONFIG_SAM0_RTC_TIMER sam0_rtc_timer.c)
 zephyr_library_sources_ifdef(CONFIG_SILABS_SLEEPTIMER_TIMER silabs_sleeptimer_timer.c)
 zephyr_library_sources_ifdef(CONFIG_STM32_LPTIM_TIMER stm32_lptim_timer.c)
+zephyr_library_sources_ifdef(CONFIG_STM32WB0_RADIO_TIMER stm32wb0_radio_timer.c)
 zephyr_library_sources_ifdef(CONFIG_TI_DM_TIMER ti_dmtimer.c)
 zephyr_library_sources_ifdef(CONFIG_XLNX_PSTTC_TIMER xlnx_psttc_timer.c)
 zephyr_library_sources_ifdef(CONFIG_XTENSA_TIMER xtensa_sys_timer.c)

drivers/timer/Kconfig

@@ -98,6 +98,7 @@ source "drivers/timer/Kconfig.sam0_rtc"
 source "drivers/timer/Kconfig.silabs"
 source "drivers/timer/Kconfig.smartbond"
 source "drivers/timer/Kconfig.stm32_lptim"
+source "drivers/timer/Kconfig.stm32wb0_radio_timer"
 source "drivers/timer/Kconfig.ti_dm_timer"
 source "drivers/timer/Kconfig.xlnx_psttc"
 source "drivers/timer/Kconfig.xtensa"

drivers/timer/Kconfig.stm32wb0_radio_timer

@@ -0,0 +1,13 @@
+# STM32WB0x radio timer configuration options
+
+# Copyright (c) 2025 STMicroelectronics
+# SPDX-License-Identifier: Apache-2.0
+
+config STM32WB0_RADIO_TIMER
+	bool "STM32 Radio Timer for WB0x"
+	default y if BT
+	depends on SOC_SERIES_STM32WB0X
+	select USE_STM32_HAL_RADIO_TIMER
+	select HAS_STM32LIB
+	select TICKLESS_CAPABLE
+	select SYSTEM_TIMER_HAS_DISABLE_SUPPORT

drivers/timer/stm32wb0_radio_timer.c

@@ -18,7 +18,7 @@
 LOG_MODULE_REGISTER(radio_timer_driver);
 
 /* Max HS startup time expressed in system time (1953 us / 2.4414 us) */
-#define MAX_HS_STARTUP_TIME	320
+#define MAX_HS_STARTUP_TIME	DT_PROP(DT_NODELABEL(radio_timer), max_hs_startup_time)
 #define BLE_WKUP_PRIO		0
 #define CPU_WKUP_PRIO		1
 #define RADIO_TIMER_ERROR_PRIO	3

dts/arm/st/wb0/stm32wb0.dtsi

@@ -297,6 +297,13 @@
 		compatible = "st,hci-stm32wb0";
 		status = "disabled";
 	};
+
+	radio_timer: radio_timer {
+		compatible = "st,stm32wb0-radio-timer";
+		compensated-timer-freq = <409600>;
+		max-hs-startup-time = <320>;
+		status = "disabled";
+	};
 };
 
 &nvic {

dts/bindings/timer/st,stm32wb0-radio-timer.yaml

@@ -0,0 +1,27 @@
+# Copyright (c) 2025, STMicroelectronics
+# SPDX-License-Identifier: Apache-2.0
+
+description: STM32WB0 Bluetooth LE Radio Timer
+
+compatible: "st,stm32wb0-radio-timer"
+
+properties:
+  compensated-timer-freq:
+    type: int
+    required: true
+    const: 409600
+    description: |
+      Timer frequency resulting from LSI or LSE frequency with interpolated value from HSE with
+      a periodic temperature compensation algorithm.
+      It is independent of hardware oscillator variations due to temperature.
+      The timer resolution is equivalent to 625/256 μs (approximately 2.4414 μs).
+      The value is expressed in hertz (Hz).
+
+  max-hs-startup-time:
+    type: int
+    required: true
+    description: |
+      High speed crystal startup time. This is used by hardware to anticipate wake-up event
+      so that high speed crystal is ready at the desired time. This parameter depends on the board
+      and the crystal used. It is expressed in the unit of 625/256 μs (approximately 2.4414 μs).
+      For example, if the property is set to 320, it means approximately 781 μs are needed.