nimble/ll: Refactor transitions

New Bluetooth features require fast RX-to-RX and TX-to-TX transitions
and use a different TIFS than 150us.

Co-authored-by: Andrzej Kaczmarek <[email protected]>

nimble/controller/include/controller/ble_phy.h

@@ -62,10 +62,11 @@ struct os_mbuf;
 #define BLE_PHY_STATE_TX            (2)
 
 /* BLE PHY transitions */
-#define BLE_PHY_TRANSITION_NONE     (0)
-#define BLE_PHY_TRANSITION_RX_TX    (1)
-#define BLE_PHY_TRANSITION_TX_RX    (2)
-#define BLE_PHY_TRANSITION_TX_TX    (3)
+#define BLE_PHY_TRANSITION_NONE                (0)
+#define BLE_PHY_TRANSITION_TO_TX               (1)
+#define BLE_PHY_TRANSITION_TO_RX               (2)
+#define BLE_PHY_TRANSITION_TO_TX_ISO_SUBEVENT  (3)
+#define BLE_PHY_TRANSITION_TO_RX_ISO_SUBEVENT  (4)
 
 /* PHY error codes */
 #define BLE_PHY_ERR_RADIO_STATE     (1)
@@ -88,14 +89,8 @@ int ble_phy_init(void);
 int ble_phy_setchan(uint8_t chan, uint32_t access_addr, uint32_t crcinit);
 uint8_t ble_phy_chan_get(void);
 
-#if MYNEWT_VAL(BLE_PHY_VARIABLE_TIFS)
-/* Set T_ifs time for next transition */
-void ble_phy_tifs_set(uint16_t tifs);
-#endif
-
-/* Set T_ifs for tx-tx transitions. Anchor is 0 for start of previous PDU,
- * non-zero for end of PDU */
-void ble_phy_tifs_txtx_set(uint16_t usecs, uint8_t anchor);
+/* Set direction of the next transition */
+void ble_phy_transition_set(uint8_t trans, uint16_t usecs);
 
 /* Set transmit start time */
 int ble_phy_tx_set_start_time(uint32_t cputime, uint8_t rem_usecs);
@@ -110,7 +105,7 @@ typedef uint8_t (*ble_phy_tx_pducb_t)(uint8_t *dptr, void *pducb_arg,
                                       uint8_t *hdr_byte);
 
 /* Place the PHY into transmit mode */
-int ble_phy_tx(ble_phy_tx_pducb_t pducb, void *pducb_arg, uint8_t end_trans);
+int ble_phy_tx(ble_phy_tx_pducb_t pducb, void *pducb_arg);
 
 /* Copies the received PHY buffer into the allocated pdu */
 void ble_phy_rxpdu_copy(uint8_t *dptr, struct os_mbuf *rxpdu);

nimble/controller/src/ble_ll_adv.c

@@ -1121,7 +1121,6 @@ static int
 ble_ll_adv_tx_start_cb(struct ble_ll_sched_item *sch)
 {
     int rc;
-    uint8_t end_trans;
     uint32_t txstart;
     struct ble_ll_adv_sm *advsm;
 
@@ -1183,18 +1182,18 @@ ble_ll_adv_tx_start_cb(struct ble_ll_sched_item *sch)
     if ((advsm->props & BLE_HCI_LE_SET_EXT_ADV_PROP_LEGACY) &&
             ((advsm->props & BLE_HCI_LE_SET_EXT_ADV_PROP_CONNECTABLE) ||
              (advsm->props & BLE_HCI_LE_SET_EXT_ADV_PROP_SCANNABLE))) {
-        end_trans = BLE_PHY_TRANSITION_TX_RX;
+        ble_phy_transition_set(BLE_PHY_TRANSITION_TO_RX, BLE_LL_IFS);
         ble_phy_set_txend_cb(NULL, NULL);
     } else {
-        end_trans = BLE_PHY_TRANSITION_NONE;
+        ble_phy_transition_set(BLE_PHY_TRANSITION_NONE, 0);
         ble_phy_set_txend_cb(ble_ll_adv_tx_done, advsm);
     }
 
     /* Transmit advertisement */
 #if MYNEWT_VAL(BLE_LL_CFG_FEAT_LL_EXT_ADV)
-    rc = ble_phy_tx(ble_ll_adv_pdu_make, advsm, end_trans);
+    rc = ble_phy_tx(ble_ll_adv_pdu_make, advsm);
 #else
-    rc = ble_phy_tx(ble_ll_adv_legacy_pdu_make, advsm, end_trans);
+    rc = ble_phy_tx(ble_ll_adv_legacy_pdu_make, advsm);
 #endif
     if (rc) {
         goto adv_tx_done;
@@ -1268,7 +1267,6 @@ static int
 ble_ll_adv_secondary_tx_start_cb(struct ble_ll_sched_item *sch)
 {
     int rc;
-    uint8_t end_trans;
     uint32_t txstart;
     struct ble_ll_adv_sm *advsm;
     ble_phy_tx_pducb_t pducb;
@@ -1319,22 +1317,22 @@ ble_ll_adv_secondary_tx_start_cb(struct ble_ll_sched_item *sch)
 
     /* Set phy mode based on type of advertisement */
     if (advsm->props & BLE_HCI_LE_SET_EXT_ADV_PROP_CONNECTABLE) {
-        end_trans = BLE_PHY_TRANSITION_TX_RX;
+        ble_phy_transition_set(BLE_PHY_TRANSITION_TO_RX, BLE_LL_IFS);
         ble_phy_set_txend_cb(NULL, NULL);
         pducb = ble_ll_adv_aux_pdu_make;
     } else if ((advsm->props & BLE_HCI_LE_SET_EXT_ADV_PROP_SCANNABLE) &&
                advsm->aux_first_pdu) {
-        end_trans = BLE_PHY_TRANSITION_TX_RX;
+        ble_phy_transition_set(BLE_PHY_TRANSITION_TO_RX, BLE_LL_IFS);
         ble_phy_set_txend_cb(NULL, NULL);
         pducb = ble_ll_adv_aux_scannable_pdu_make;
     } else {
-        end_trans = BLE_PHY_TRANSITION_NONE;
+        ble_phy_transition_set(BLE_PHY_TRANSITION_NONE, 0);
         ble_phy_set_txend_cb(ble_ll_adv_tx_done, advsm);
         pducb = ble_ll_adv_aux_pdu_make;
     }
 
     /* Transmit advertisement */
-    rc = ble_phy_tx(pducb, advsm, end_trans);
+    rc = ble_phy_tx(pducb, advsm);
     if (rc) {
         goto adv_aux_dropped;
     }
@@ -2322,8 +2320,9 @@ ble_ll_adv_sync_tx_start_cb(struct ble_ll_sched_item *sch)
 #endif
 
     /* Transmit advertisement */
+    ble_phy_transition_set(BLE_PHY_TRANSITION_NONE, 0);
     ble_phy_set_txend_cb(ble_ll_adv_sync_tx_end, advsm);
-    rc = ble_phy_tx(ble_ll_adv_sync_pdu_make, advsm, BLE_PHY_TRANSITION_NONE);
+    rc = ble_phy_tx(ble_ll_adv_sync_pdu_make, advsm);
     if (rc) {
         goto adv_tx_done;
     }
@@ -4547,6 +4546,8 @@ ble_ll_adv_rx_req(uint8_t pdu_type, struct os_mbuf *rxpdu)
          */
         ble_phy_set_txend_cb(ble_ll_adv_tx_done, advsm);
 
+        ble_phy_transition_set(BLE_PHY_TRANSITION_NONE, 0);
+
 #if MYNEWT_VAL(BLE_LL_CFG_FEAT_LL_EXT_ADV)
         if (advsm->flags & BLE_LL_ADV_SM_FLAG_SCAN_REQ_NOTIF) {
             ble_ll_hci_ev_send_scan_req_recv(advsm->adv_instance, peer,
@@ -4560,12 +4561,10 @@ ble_ll_adv_rx_req(uint8_t pdu_type, struct os_mbuf *rxpdu)
          */
 
         advsm->rx_ble_hdr = ble_hdr;
-        rc = ble_phy_tx(ble_ll_adv_scan_rsp_pdu_make, advsm,
-                        BLE_PHY_TRANSITION_NONE);
+        rc = ble_phy_tx(ble_ll_adv_scan_rsp_pdu_make, advsm);
         advsm->rx_ble_hdr = NULL;
 #else
-        rc = ble_phy_tx(ble_ll_adv_scan_rsp_legacy_pdu_make, advsm,
-                        BLE_PHY_TRANSITION_NONE);
+        rc = ble_phy_tx(ble_ll_adv_scan_rsp_legacy_pdu_make, advsm);
 #endif
 
         if (!rc) {
@@ -4599,9 +4598,9 @@ ble_ll_adv_rx_req(uint8_t pdu_type, struct os_mbuf *rxpdu)
         rsp_data.peer = rxbuf + BLE_LL_PDU_HDR_LEN;
         rsp_data.rxadd = rxbuf[0] & BLE_ADV_PDU_HDR_TXADD_MASK;
 
+        ble_phy_transition_set(BLE_PHY_TRANSITION_NONE, 0);
         ble_phy_set_txend_cb(ble_ll_adv_tx_done, advsm);
-        rc = ble_phy_tx(ble_ll_adv_aux_conn_rsp_pdu_make, &rsp_data,
-                        BLE_PHY_TRANSITION_NONE);
+        rc = ble_phy_tx(ble_ll_adv_aux_conn_rsp_pdu_make, &rsp_data);
         if (!rc) {
             ble_ll_adv_flags_set(advsm, BLE_LL_ADV_SM_FLAG_CONN_RSP_TXD);
             STATS_INC(ble_ll_stats, aux_conn_rsp_tx);
@@ -4892,6 +4891,8 @@ ble_ll_adv_rx_isr_start(uint8_t pdu_type)
      */
     if (rc < 0) {
         ble_ll_adv_tx_done(advsm);
+    } else if (rc > 0){
+        ble_phy_transition_set(BLE_PHY_TRANSITION_TO_TX, BLE_LL_IFS);
     }
 
     return rc;

nimble/controller/src/ble_ll_conn.c

@@ -1347,7 +1347,7 @@ ble_ll_conn_tx_pdu(struct ble_ll_conn_sm *connsm)
         txend_func = ble_ll_conn_wait_txend;
     } else {
         /* Wait for a response here */
-        end_transition = BLE_PHY_TRANSITION_TX_RX;
+        end_transition = BLE_PHY_TRANSITION_TO_RX;
         txend_func = NULL;
     }
 
@@ -1435,9 +1435,9 @@ ble_ll_conn_tx_pdu(struct ble_ll_conn_sm *connsm)
     }
 #endif
 
-    /* Set transmit end callback */
+    ble_phy_transition_set(end_transition, BLE_LL_IFS);
     ble_phy_set_txend_cb(txend_func, connsm);
-    rc = ble_phy_tx(ble_ll_tx_mbuf_pducb, m, end_transition);
+    rc = ble_phy_tx(ble_ll_tx_mbuf_pducb, m);
     if (!rc) {
         /* Log transmit on connection state */
         cur_txlen = ble_hdr->txinfo.pyld_len;
@@ -3269,9 +3269,11 @@ ble_ll_conn_send_connect_req(struct os_mbuf *rxpdu,
     ble_ll_conn_prepare_connect_ind(connsm, ble_ll_scan_get_pdu_data(), addrd,
                                     rxhdr->rxinfo.channel);
 
+    ble_phy_transition_set(ext ? BLE_PHY_TRANSITION_TO_RX :
+                                 BLE_PHY_TRANSITION_NONE,
+                           BLE_LL_IFS);
     ble_phy_set_txend_cb(NULL, NULL);
-    rc = ble_phy_tx(ble_ll_conn_tx_connect_ind_pducb, connsm,
-                    ext ? BLE_PHY_TRANSITION_TX_RX : BLE_PHY_TRANSITION_NONE);
+    rc = ble_phy_tx(ble_ll_conn_tx_connect_ind_pducb, connsm);
     if (rc) {
         ble_ll_conn_send_connect_req_cancel();
         return -1;

nimble/controller/src/ble_ll_dtm.c

@@ -244,7 +244,8 @@ ble_ll_dtm_tx_sched_cb(struct ble_ll_sched_item *sch)
         goto resched;
     }
 
-    rc = ble_phy_tx(ble_ll_tx_mbuf_pducb, ctx->om, BLE_PHY_TRANSITION_NONE);
+    ble_phy_transition_set(BLE_PHY_TRANSITION_NONE, 0);
+    rc = ble_phy_tx(ble_ll_tx_mbuf_pducb, ctx->om);
     if (rc) {
         goto resched;
     }

nimble/controller/src/ble_ll_iso_big.c

@@ -688,7 +688,8 @@ ble_ll_iso_big_control_tx(struct ble_ll_iso_big *big)
     ble_phy_set_txend_cb(ble_ll_iso_big_control_txend_cb, big);
     ble_phy_setchan(chan_idx, big->ctrl_aa, big->crc_init << 8);
 
-    rc = ble_phy_tx(ble_ll_iso_big_control_pdu_cb, big, BLE_PHY_TRANSITION_NONE);
+    ble_phy_transition_set(BLE_PHY_TRANSITION_NONE, 0);
+    rc = ble_phy_tx(ble_ll_iso_big_control_pdu_cb, big);
 
     return rc;
 }
@@ -773,9 +774,12 @@ ble_ll_iso_big_subevent_tx(struct ble_ll_iso_big *big)
 
     to_tx = (big->tx.subevents_rem > 1) || big->cstf;
 
-    rc = ble_phy_tx(ble_ll_iso_big_subevent_pdu_cb, big,
-                    to_tx ? BLE_PHY_TRANSITION_TX_TX
-                          : BLE_PHY_TRANSITION_NONE);
+    ble_phy_transition_set(to_tx ? BLE_PHY_TRANSITION_TO_TX_ISO_SUBEVENT :
+                                   BLE_PHY_TRANSITION_NONE,
+                           big->interleaved ? big->bis_spacing :
+                                              big->sub_interval);
+
+    rc = ble_phy_tx(ble_ll_iso_big_subevent_pdu_cb, big);
     return rc;
 }
 
@@ -874,12 +878,6 @@ ble_ll_iso_big_event_sched_cb(struct ble_ll_sched_item *sch)
     big->tx.bis = STAILQ_FIRST(&big->bis_q);
     big->tx.bis->tx.subevent_num = 1;
 
-    if (big->interleaved) {
-        ble_phy_tifs_txtx_set(big->bis_spacing, 0);
-    } else {
-        ble_phy_tifs_txtx_set(big->sub_interval, 0);
-    }
-
     rc = ble_phy_tx_set_start_time(sch->start_time + g_ble_ll_sched_offset_ticks,
                                    sch->remainder);
     if (rc) {

nimble/controller/src/ble_ll_scan.c

@@ -1563,7 +1563,8 @@ ble_ll_scan_send_scan_req(uint8_t pdu_type, uint8_t *rxbuf,
     ble_ll_scan_req_pdu_prepare(scansm, addrd->adva, addrd->adva_type,
                                 rpa_index);
 
-    rc = ble_phy_tx(ble_ll_scan_req_tx_pdu_cb, scansm, BLE_PHY_TRANSITION_TX_RX);
+    ble_phy_transition_set(BLE_PHY_TRANSITION_TO_RX, BLE_LL_IFS);
+    rc = ble_phy_tx(ble_ll_scan_req_tx_pdu_cb, scansm);
     if (rc) {
         return false;
     }

nimble/controller/src/ble_ll_scan_aux.c

@@ -1226,8 +1226,8 @@ ble_ll_scan_aux_send_scan_req(struct ble_ll_scan_aux_data *aux,
      *      interrupted if scheduler kicks in.
      */
 
-    rc = ble_phy_tx(ble_ll_scan_aux_scan_req_tx_pdu_cb, aux,
-                    BLE_PHY_TRANSITION_TX_RX);
+    ble_phy_transition_set(BLE_PHY_TRANSITION_TO_RX, BLE_LL_IFS);
+    rc = ble_phy_tx(ble_ll_scan_aux_scan_req_tx_pdu_cb, aux);
     if (rc) {
         return false;
     }

nimble/drivers/dialog_cmac/src/ble_phy.c

@@ -580,7 +580,7 @@ ble_phy_irq_field_tx_exc_bs_start_4this(void)
 {
     CMAC->CM_EXC_STAT_REG = CMAC_CM_EXC_STAT_REG_EXC_BS_START_4THIS_Msk;
 
-    if (g_ble_phy_data.end_transition == BLE_PHY_TRANSITION_TX_RX) {
+    if (g_ble_phy_data.end_transition == BLE_PHY_TRANSITION_TO_RX) {
         /*
          * Setup 2nd frame that will start after current one.
          * -2us offset to adjust for allowed active clock accuracy.
@@ -642,7 +642,7 @@ ble_phy_irq_frame_tx_exc_bs_stop(void)
     /* Clear latched timestamp so we do not have error on next frame */
     (void)CMAC->CM_TS1_REG;
 
-    if (g_ble_phy_data.end_transition == BLE_PHY_TRANSITION_TX_RX) {
+    if (g_ble_phy_data.end_transition == BLE_PHY_TRANSITION_TO_RX) {
 #if MYNEWT_VAL(BLE_LL_PHY)
         ble_phy_mode_apply(g_ble_phy_data.phy_mode_rx);
 #endif
@@ -665,7 +665,7 @@ ble_phy_irq_frame_tx_exc_phy_to_idle_4this(void)
 {
     CMAC->CM_EXC_STAT_REG = CMAC_CM_EXC_STAT_REG_EXC_PHY_TO_IDLE_4THIS_Msk;
 
-    if (g_ble_phy_data.end_transition == BLE_PHY_TRANSITION_TX_RX) {
+    if (g_ble_phy_data.end_transition == BLE_PHY_TRANSITION_TO_RX) {
         ble_phy_rx_setup_xcvr();
 
         g_ble_phy_data.phy_state = BLE_PHY_STATE_RX;
@@ -1403,7 +1403,7 @@ ble_phy_rx_set_start_time(uint32_t cputime, uint8_t rem_usecs)
 }
 
 int
-ble_phy_tx(ble_phy_tx_pducb_t pducb, void *pducb_arg, uint8_t end_trans)
+ble_phy_tx(ble_phy_tx_pducb_t pducb, void *pducb_arg)
 {
     uint8_t *txbuf = g_ble_phy_tx_buf;
     int rc;
@@ -1412,8 +1412,6 @@ ble_phy_tx(ble_phy_tx_pducb_t pducb, void *pducb_arg, uint8_t end_trans)
 
     assert(CMAC->CM_FRAME_1_REG & CMAC_CM_FRAME_1_REG_FRAME_TX_Msk);
 
-    g_ble_phy_data.end_transition = end_trans;
-
     /*
      * Program required fields now so in worst case TX can continue while we
      * are still preparing header and payload.
@@ -1829,3 +1827,9 @@ ble_phy_dtm_carrier(uint8_t rf_channel)
 }
 #endif
 #endif
+
+void
+ble_phy_transition_set(uint8_t trans, uint16_t usecs)
+{
+    g_ble_phy_data.end_transition = trans;
+}

nimble/drivers/native/src/ble_phy.c

@@ -241,7 +241,7 @@ ble_phy_isr(void)
         ble_xcvr_clear_irq(BLE_XCVR_IRQ_F_TX_END);
 
         transition = g_ble_phy_data.phy_transition;
-        if (transition == BLE_PHY_TRANSITION_TX_RX) {
+        if (transition == BLE_PHY_TRANSITION_TO_RX) {
             /* Disable the phy */
             /* XXX: count no bufs? */
             ble_phy_disable();
@@ -422,7 +422,7 @@ ble_phy_rx_set_start_time(uint32_t cputime, uint8_t rem_usecs)
 
 
 int
-ble_phy_tx(ble_phy_tx_pducb_t pducb, void *pducb_arg, uint8_t end_trans)
+ble_phy_tx(ble_phy_tx_pducb_t pducb, void *pducb_arg)
 {
     uint8_t hdr_byte;
     int rc;
@@ -440,9 +440,6 @@ ble_phy_tx(ble_phy_tx_pducb_t pducb, void *pducb_arg, uint8_t end_trans)
     } else {
     }
 
-    /* Set the PHY transition */
-    g_ble_phy_data.phy_transition = end_trans;
-
     /* Set phy state to transmitting and count packet statistics */
     g_ble_phy_data.phy_state = BLE_PHY_STATE_TX;
     ++g_ble_phy_stats.tx_good;
@@ -662,6 +659,7 @@ ble_phy_rfclk_disable(void)
 }
 
 void
-ble_phy_tifs_txtx_set(uint16_t usecs, uint8_t anchor)
+ble_phy_transition_set(uint8_t trans, uint16_t usecs)
 {
+    g_ble_phy_data.phy_transition = trans;
 }