Bluetooth: Controller: Add advertiser clock accuracy value

Add implementation to set correct Advertiser's clock
accuracy value in the auxiliary pointer field in the common
extended payload format.

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

Author: cvinayak

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

@@ -403,8 +403,8 @@ static void pdu_b2b_aux_ptr_update(struct pdu_adv *pdu, uint8_t phy, uint8_t fla
 				   uint8_t chan_idx, uint32_t offset_us, uint32_t cte_len_us)
 {
 	struct pdu_adv_com_ext_adv *com_hdr;
+	struct pdu_adv_aux_ptr *aux_ptr;
 	struct pdu_adv_ext_hdr *hdr;
-	struct pdu_adv_aux_ptr *aux;
 	uint8_t *dptr;
 
 	com_hdr = &pdu->adv_ext_ind;
@@ -426,7 +426,7 @@ static void pdu_b2b_aux_ptr_update(struct pdu_adv *pdu, uint8_t phy, uint8_t fla
 	LL_ASSERT(!hdr->adi);
 
 	/* Update AuxPtr */
-	aux = (void *)dptr;
+	aux_ptr = (void *)dptr;
 	offset_us += PDU_AC_US(pdu->len, phy, flags);
 	/* Add CTE length to PDUs that have CTE attached.
 	 * Periodic advertising chain may include PDUs without CTE.
@@ -436,15 +436,16 @@ static void pdu_b2b_aux_ptr_update(struct pdu_adv *pdu, uint8_t phy, uint8_t fla
 	}
 	offset_us = offset_us / OFFS_UNIT_30_US;
 	if ((offset_us >> 13) != 0) {
-		aux->offs = offset_us / (OFFS_UNIT_300_US / OFFS_UNIT_30_US);
-		aux->offs_units = 1U;
+		aux_ptr->offs = offset_us / (OFFS_UNIT_300_US / OFFS_UNIT_30_US);
+		aux_ptr->offs_units = 1U;
 	} else {
-		aux->offs = offset_us;
-		aux->offs_units = 0U;
+		aux_ptr->offs = offset_us;
+		aux_ptr->offs_units = 0U;
 	}
-	aux->chan_idx = chan_idx;
-	aux->ca = 0;
-	aux->phy = find_lsb_set(phy) - 1;
+	aux_ptr->chan_idx = chan_idx;
+	aux_ptr->ca = (lll_clock_ppm_local_get() <= SCA_50_PPM) ?
+		      SCA_VALUE_50_PPM : SCA_VALUE_500_PPM;
+	aux_ptr->phy = find_lsb_set(phy) - 1;
 }
 
 static void switch_radio_complete_and_b2b_tx(const struct lll_adv_sync *lll, uint8_t phy_s)

subsys/bluetooth/controller/ll_sw/pdu.h

@@ -108,6 +108,12 @@
 /* Value specified in BT Spec. Vol 6, Part B, section 2.3.4.6 */
 #define OFFS_ADJUST_US          245760
 
+/* Advertiser's Sleep Clock Accuracy Value */
+#define SCA_500_PPM       500 /* 51 ppm to 500 ppm */
+#define SCA_50_PPM        50  /* 0 ppm to 50 ppm */
+#define SCA_VALUE_500_PPM 0   /* 51 ppm to 500 ppm */
+#define SCA_VALUE_50_PPM  1   /* 0 ppm to 50 ppm */
+
 /* Sleep Clock Accuracy, calculate drift in microseconds */
 #define SCA_DRIFT_50_PPM_US(t)  (((t) * 50UL) / 1000000UL)
 #define SCA_DRIFT_500_PPM_US(t) (((t) * 500UL) / 1000000UL)

subsys/bluetooth/controller/ll_sw/ull_adv_aux.c

@@ -22,6 +22,7 @@
 #include "pdu.h"
 
 #include "lll.h"
+#include "lll_clock.h"
 #include "lll/lll_vendor.h"
 #include "lll/lll_adv_types.h"
 #include "lll_adv.h"
@@ -907,7 +908,9 @@ void ull_adv_aux_ptr_fill(uint8_t **dptr, uint8_t phy_s)
 
 	/* FIXME: implementation defined */
 	aux_ptr->chan_idx = 0U;
-	aux_ptr->ca = 0U;
+
+	aux_ptr->ca = (lll_clock_ppm_local_get() <= SCA_50_PPM) ?
+		      SCA_VALUE_50_PPM : SCA_VALUE_500_PPM;
 
 	/* NOTE: Aux Offset will be set in advertiser LLL event
 	 */