Bluetooth: controller: radio: Add back2back TX switch after PHYEND event

Transmission of Constant Tone Extension is done after END event
triggered by radio. To correctly switch from TX to TX (back 2 back
TX) after transmission of CTE PHYEND event must be used instead of
END event.

The commit provides required function that allows LLL to correctly
setup radio to do back to back switch of TX when CTE transmission
is enabled.

The radio_switch_complete_and_phy_end_b2b_tx cannot be implemented
in radio.c source file. It will fail build of unit tests targeted
for NRFBSIM simulator board. There is no RADIO_SHORTS_PHYEND_DISABLE_Msk
macro defined in bsim_hw_models module.

Signed-off-by: Piotr Pryga <[email protected]>

Author: ppryga-nordic

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

@@ -21,6 +21,8 @@
 
 #include "ll_sw/pdu.h"
 
+#include "radio_internal.h"
+
 #if defined(CONFIG_BT_CTLR_GPIO_PA_PIN)
 #if ((CONFIG_BT_CTLR_GPIO_PA_PIN) > 31)
 #define NRF_GPIO_PA     NRF_P1
@@ -490,19 +492,10 @@ void *radio_pkt_decrypt_get(void)
 
 #if !defined(CONFIG_BT_CTLR_TIFS_HW)
 
-#define SW_SWITCH_PREV_RX             0
-#define SW_SWITCH_NEXT_RX             0
-#define SW_SWITCH_PREV_TX             1
-#define SW_SWITCH_NEXT_TX             1
-#define SW_SWITCH_PREV_PHY_1M         0
-#define SW_SWITCH_PREV_FLAGS_DONTCARE 0
-#define SW_SWITCH_NEXT_FLAGS_DONTCARE 0
-
 static uint8_t sw_tifs_toggle;
 
-static inline void sw_switch(uint8_t dir_curr, uint8_t dir_next,
-			     uint8_t phy_curr, uint8_t flags_curr,
-			     uint8_t phy_next, uint8_t flags_next)
+void sw_switch(uint8_t dir_curr, uint8_t dir_next, uint8_t phy_curr, uint8_t flags_curr,
+	       uint8_t phy_next, uint8_t flags_next)
 {
 	uint8_t ppi = HAL_SW_SWITCH_RADIO_ENABLE_PPI(sw_tifs_toggle);
 	uint8_t cc = SW_SWITCH_TIMER_EVTS_COMP(sw_tifs_toggle);
@@ -511,8 +504,8 @@ static inline void sw_switch(uint8_t dir_curr, uint8_t dir_next,
 	hal_radio_sw_switch_setup(cc, ppi, sw_tifs_toggle);
 
 	/* NOTE: As constants are passed to dir_curr and dir_next, the
-	 *       compiler should optimize out the redundant code path as
-	 *       this is an inline function.
+	 *       compiler should optimize out the redundant code path
+	 *       during the optimization.
 	 */
 	if (dir_next) {
 		/* TX */
@@ -649,9 +642,8 @@ void radio_switch_complete_and_rx(uint8_t phy_rx)
 	 *	 across nRF5x radios, sw_switch assumes the 1M chain delay for
 	 *       calculations.
 	 */
-	sw_switch(SW_SWITCH_PREV_TX, SW_SWITCH_NEXT_RX,
-		  SW_SWITCH_PREV_PHY_1M, SW_SWITCH_PREV_FLAGS_DONTCARE,
-		  phy_rx, SW_SWITCH_NEXT_FLAGS_DONTCARE);
+	sw_switch(SW_SWITCH_TX, SW_SWITCH_RX, SW_SWITCH_PHY_1M, SW_SWITCH_FLAGS_DONTCARE, phy_rx,
+		  SW_SWITCH_FLAGS_DONTCARE);
 #endif /* !CONFIG_BT_CTLR_TIFS_HW */
 }
 
@@ -666,8 +658,7 @@ void radio_switch_complete_and_tx(uint8_t phy_rx, uint8_t flags_rx,
 	NRF_RADIO->SHORTS = RADIO_SHORTS_READY_START_Msk |
 			    RADIO_SHORTS_END_DISABLE_Msk;
 
-	sw_switch(SW_SWITCH_PREV_RX, SW_SWITCH_NEXT_TX,
-		  phy_rx, flags_rx, phy_tx, flags_tx);
+	sw_switch(SW_SWITCH_RX, SW_SWITCH_TX, phy_rx, flags_rx, phy_tx, flags_tx);
 #endif /* !CONFIG_BT_CTLR_TIFS_HW */
 }
 
@@ -682,8 +673,7 @@ void radio_switch_complete_and_b2b_tx(uint8_t phy_curr, uint8_t flags_curr,
 	NRF_RADIO->SHORTS = RADIO_SHORTS_READY_START_Msk |
 			    RADIO_SHORTS_END_DISABLE_Msk;
 
-	sw_switch(SW_SWITCH_PREV_TX, SW_SWITCH_NEXT_TX,
-		  phy_curr, flags_curr, phy_next, flags_next);
+	sw_switch(SW_SWITCH_TX, SW_SWITCH_TX, phy_curr, flags_curr, phy_next, flags_next);
 #endif /* !CONFIG_BT_CTLR_TIFS_HW */
 }
 

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

@@ -13,6 +13,7 @@
 
 #include "radio_nrf5.h"
 #include "radio_df.h"
+#include "radio_internal.h"
 
 /* @brief Minimum antennas number required if antenna switching is enabled */
 #define DF_ANT_NUM_MIN 2
@@ -359,6 +360,18 @@ void radio_switch_complete_and_phy_end_disable(void)
 #endif /* !CONFIG_BT_CTLR_TIFS_HW */
 }
 
+void radio_switch_complete_and_phy_end_b2b_tx(uint8_t phy_curr, uint8_t flags_curr,
+					      uint8_t phy_next, uint8_t flags_next)
+{
+#if defined(CONFIG_BT_CTLR_TIFS_HW)
+	NRF_RADIO->SHORTS = RADIO_SHORTS_READY_START_Msk | RADIO_SHORTS_PHYEND_DISABLE_Msk |
+			    RADIO_SHORTS_DISABLED_TXEN_Msk;
+#else /* !CONFIG_BT_CTLR_TIFS_HW */
+	NRF_RADIO->SHORTS = RADIO_SHORTS_READY_START_Msk | RADIO_SHORTS_PHYEND_DISABLE_Msk;
+	sw_switch(SW_SWITCH_TX, SW_SWITCH_TX, phy_curr, flags_curr, phy_next, flags_next);
+#endif /* !CONFIG_BT_CTLR_TIFS_HW */
+}
+
 void radio_df_iq_data_packet_set(uint8_t *buffer, size_t len)
 {
 	nrf_radio_dfe_buffer_set(NRF_RADIO, (uint32_t *)buffer, len);

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

@@ -50,6 +50,10 @@ void radio_df_reset(void);
 /* Completes switching and enables shortcut between PHYEND and DISABLE events */
 void radio_switch_complete_and_phy_end_disable(void);
 
+/* Completes switching and enables shortcut between PHYEND and TXEN events */
+void radio_switch_complete_and_phy_end_b2b_tx(uint8_t phy_curr, uint8_t flags_curr,
+					      uint8_t phy_next, uint8_t flags_next);
+
 /* Enables CTE inline configuration to automatically setup sampling and
  * switching according to CTEInfo in received PDU.
  */

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

@@ -0,0 +1,13 @@
+/*
+ * Copyright (c) 2021 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define SW_SWITCH_RX 0
+#define SW_SWITCH_TX 1
+#define SW_SWITCH_PHY_1M 0
+#define SW_SWITCH_FLAGS_DONTCARE 0
+
+void sw_switch(uint8_t dir_curr, uint8_t dir_next, uint8_t phy_curr, uint8_t flags_curr,
+	       uint8_t phy_next, uint8_t flags_next);