Bluetooth: Controller: Add radio timer ISR usage support

Add radio timer ISR usage support.

Signed-off-by: Vinayak Kariappa Chettimada <[email protected]>

Author: cvinayak

subsys/bluetooth/controller/Kconfig.ll_sw_split

@@ -900,6 +900,13 @@ config BT_CTLR_RADIO_ENABLE_FAST
 	help
 	  Enable use of fast radio ramp-up mode.
 
+config BT_CTLR_RADIO_TIMER_ISR
+	# Hidden, enables use of timer ISR callback
+	bool
+	depends on SOC_COMPATIBLE_NRF52X || SOC_COMPATIBLE_NRF53X
+	help
+	  Enables use of timer ISR callback.
+
 config BT_CTLR_TIFS_HW
 	bool "H/w Accelerated tIFS Trx switching"
 	depends on !BT_CTLR_RADIO_ENABLE_FAST && BT_CTLR_TIFS_HW_SUPPORT

subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/radio/radio.c

@@ -1153,6 +1153,56 @@ uint32_t radio_bc_has_match(void)
 	return (NRF_RADIO->EVENTS_BCMATCH != 0);
 }
 
+#if defined(CONFIG_BT_CTLR_RADIO_TIMER_ISR)
+static radio_isr_cb_t isr_radio_tmr_cb;
+static void           *isr_radio_tmr_cb_param;
+
+void isr_radio_tmr(void)
+{
+	irq_disable(TIMER0_IRQn);
+	nrf_timer_int_disable(EVENT_TIMER, TIMER_INTENSET_COMPARE2_Msk);
+	nrf_timer_event_clear(EVENT_TIMER, HAL_EVENT_TIMER_DEFERRED_TX_EVENT);
+
+	isr_radio_tmr_cb(isr_radio_tmr_cb_param);
+}
+
+uint32_t radio_tmr_isr_set(uint32_t start_us, radio_isr_cb_t cb, void *param)
+{
+	irq_disable(TIMER0_IRQn);
+
+	isr_radio_tmr_cb_param = param;
+	isr_radio_tmr_cb = cb;
+
+	/* start_us could be the current count in the timer */
+	uint32_t now_us = start_us;
+
+	/* Setup timer compare while determining the latency in doing so */
+	do {
+		/* Set start to be, now plus the determined latency */
+		start_us = (now_us << 1) - start_us;
+
+		/* Setup compare event with min. 1 us offset */
+		nrf_timer_event_clear(EVENT_TIMER, HAL_EVENT_TIMER_DEFERRED_TX_EVENT);
+		nrf_timer_cc_set(EVENT_TIMER, HAL_EVENT_TIMER_DEFERRED_TRX_CC_OFFSET,
+				 start_us + 1U);
+
+		/* Capture the current time */
+		nrf_timer_task_trigger(EVENT_TIMER, HAL_EVENT_TIMER_SAMPLE_TASK);
+
+		now_us = EVENT_TIMER->CC[HAL_EVENT_TIMER_SAMPLE_CC_OFFSET];
+	} while ((now_us > start_us) &&
+		 (EVENT_TIMER->EVENTS_COMPARE[HAL_EVENT_TIMER_DEFERRED_TRX_CC_OFFSET] == 0U));
+
+	nrf_timer_int_enable(EVENT_TIMER, TIMER_INTENSET_COMPARE2_Msk);
+
+	NVIC_ClearPendingIRQ(TIMER0_IRQn);
+
+	irq_enable(TIMER0_IRQn);
+
+	return start_us + 1U;
+}
+#endif /* CONFIG_BT_CTLR_RADIO_TIMER_ISR */
+
 void radio_tmr_status_reset(void)
 {
 #if defined(CONFIG_BT_CTLR_NRF_GRTC)

subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/radio/radio.h

@@ -130,6 +130,9 @@ void radio_bc_configure(uint32_t n);
 void radio_bc_status_reset(void);
 uint32_t radio_bc_has_match(void);
 
+void isr_radio_tmr(void);
+uint32_t radio_tmr_isr_set(uint32_t start_us, radio_isr_cb_t cb, void *param);
+
 void radio_tmr_status_reset(void);
 void radio_tmr_tx_status_reset(void);
 void radio_tmr_rx_status_reset(void);

subsys/bluetooth/controller/ll_sw/nordic/lll/lll.c

@@ -115,6 +115,33 @@ ISR_DIRECT_DECLARE(radio_nrf5_isr)
 #endif /* !CONFIG_DYNAMIC_DIRECT_INTERRUPTS */
 }
 
+#if defined(CONFIG_BT_CTLR_RADIO_TIMER_ISR)
+#if defined(CONFIG_BT_CTLR_DYNAMIC_INTERRUPTS) && \
+	defined(CONFIG_DYNAMIC_DIRECT_INTERRUPTS)
+static void timer_nrf5_isr(const void *arg)
+#else /* !CONFIG_BT_CTLR_DYNAMIC_INTERRUPTS */
+ISR_DIRECT_DECLARE(timer_nrf5_isr)
+#endif /* !CONFIG_BT_CTLR_DYNAMIC_INTERRUPTS */
+{
+	DEBUG_RADIO_ISR(1);
+
+	lll_prof_enter_radio();
+
+	isr_radio_tmr();
+
+	ISR_DIRECT_PM();
+
+	lll_prof_exit_radio();
+
+	DEBUG_RADIO_ISR(0);
+
+#if !defined(CONFIG_BT_CTLR_DYNAMIC_INTERRUPTS) || \
+	!defined(CONFIG_DYNAMIC_DIRECT_INTERRUPTS)
+	return 1;
+#endif /* !CONFIG_DYNAMIC_DIRECT_INTERRUPTS */
+}
+#endif /* CONFIG_BT_CTLR_RADIO_TIMER_ISR */
+
 static void rtc0_nrf5_isr(const void *arg)
 {
 	DEBUG_TICKER_ISR(1);
@@ -221,9 +248,19 @@ int lll_init(void)
 				       IRQ_CONNECT_FLAGS, no_reschedule);
 	irq_connect_dynamic(HAL_RADIO_IRQn, CONFIG_BT_CTLR_LLL_PRIO,
 			    radio_nrf5_isr, NULL, IRQ_CONNECT_FLAGS);
+#if defined(CONFIG_BT_CTLR_RADIO_TIMER_ISR)
+	ARM_IRQ_DIRECT_DYNAMIC_CONNECT(TIMER0_IRQn, CONFIG_BT_CTLR_LLL_PRIO,
+				       IRQ_CONNECT_FLAGS, no_reschedule);
+	irq_connect_dynamic(TIMER0_IRQn, CONFIG_BT_CTLR_LLL_PRIO,
+			    timer_nrf5_isr, NULL, IRQ_CONNECT_FLAGS);
+#endif /* CONFIG_BT_CTLR_RADIO_TIMER_ISR */
 #else /* !CONFIG_DYNAMIC_DIRECT_INTERRUPTS */
 	IRQ_DIRECT_CONNECT(HAL_RADIO_IRQn, CONFIG_BT_CTLR_LLL_PRIO,
 			   radio_nrf5_isr, IRQ_CONNECT_FLAGS);
+#if defined(CONFIG_BT_CTLR_RADIO_TIMER_ISR)
+	IRQ_DIRECT_CONNECT(TIMER0_IRQn, CONFIG_BT_CTLR_LLL_PRIO,
+			   timer_nrf5_isr, IRQ_CONNECT_FLAGS);
+#endif /* CONFIG_BT_CTLR_RADIO_TIMER_ISR */
 #endif /* !CONFIG_DYNAMIC_DIRECT_INTERRUPTS */
 	irq_connect_dynamic(HAL_RTC_IRQn, CONFIG_BT_CTLR_ULL_HIGH_PRIO,
 			    rtc0_nrf5_isr, NULL, 0U);
@@ -238,6 +275,10 @@ int lll_init(void)
 #else /* !CONFIG_BT_CTLR_DYNAMIC_INTERRUPTS */
 	IRQ_DIRECT_CONNECT(HAL_RADIO_IRQn, CONFIG_BT_CTLR_LLL_PRIO,
 			   radio_nrf5_isr, IRQ_CONNECT_FLAGS);
+#if defined(CONFIG_BT_CTLR_RADIO_TIMER_ISR)
+	IRQ_DIRECT_CONNECT(TIMER0_IRQn, CONFIG_BT_CTLR_LLL_PRIO,
+			   timer_nrf5_isr, IRQ_CONNECT_FLAGS);
+#endif /* CONFIG_BT_CTLR_RADIO_TIMER_ISR */
 	IRQ_CONNECT(HAL_RTC_IRQn, CONFIG_BT_CTLR_ULL_HIGH_PRIO,
 		    rtc0_nrf5_isr, NULL, 0);
 #if defined(CONFIG_BT_CTLR_ZLI)
@@ -298,6 +339,10 @@ int lll_deinit(void)
 #if defined(CONFIG_DYNAMIC_DIRECT_INTERRUPTS)
 	irq_disconnect_dynamic(HAL_RADIO_IRQn, CONFIG_BT_CTLR_LLL_PRIO,
 			       radio_nrf5_isr, NULL, IRQ_CONNECT_FLAGS);
+#if defined(CONFIG_BT_CTLR_RADIO_TIMER_ISR)
+	irq_disconnect_dynamic(TIMER0_IRQn, CONFIG_BT_CTLR_LLL_PRIO,
+			       timer_nrf5_isr, NULL, IRQ_CONNECT_FLAGS);
+#endif /* CONFIG_BT_CTLR_RADIO_TIMER_ISR */
 #endif /* CONFIG_DYNAMIC_DIRECT_INTERRUPTS */
 	irq_disconnect_dynamic(HAL_RTC_IRQn, CONFIG_BT_CTLR_ULL_HIGH_PRIO,
 			       rtc0_nrf5_isr, NULL, 0U);