LC15: Fix missing fill frame and GSM 05.08 mandatory frame

Change-Id: I40e9bf9438c0b400e4d29eb39ffae37207e34db6

include/osmo-bts/msg_utils.h

@@ -32,6 +32,17 @@ enum {
 	OML_MSG_TYPE_OSMO,
 };
 
+static const uint8_t gsm_speech_zero[GSM_FR_BYTES] = {
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00
+};
+
+static const uint8_t amr_sid_first_zero[9] = {
+		0x00, 0x00, 0x00, 0x44, 0x00, 0x00, 0x00, 0x00, 0x00
+};
+
 void lchan_set_marker(bool t, struct gsm_lchan *lchan);
 bool dtx_dl_amr_enabled(const struct gsm_lchan *lchan);
 void dtx_dispatch(struct gsm_lchan *lchan, enum dtx_dl_amr_fsm_events e);

src/common/msg_utils.c

@@ -379,7 +379,7 @@ static inline bool dtx_sched_optional(struct gsm_lchan *lchan, uint32_t fn)
 	static const uint8_t f[] = { 52, 53, 54, 55, 56, 57, 58, 59 },
 				h0[] = { 0, 2, 4, 6, 52, 54, 56, 58 },
 				h1[] = { 14, 16, 18, 20, 66, 68, 70, 72 };
-	if (lchan->tch_mode == GSM48_CMODE_SPEECH_V1) {
+	if ((lchan->tch_mode == GSM48_CMODE_SPEECH_V1) || (lchan->tch_mode == GSM48_CMODE_SPEECH_AMR)){
 		if (lchan->type == GSM_LCHAN_TCH_F)
 			return fn_chk(f, fn, ARRAY_SIZE(f));
 		else
@@ -465,6 +465,7 @@ void dtx_int_signal(struct gsm_lchan *lchan)
  */
 uint8_t repeat_last_sid(struct gsm_lchan *lchan, uint8_t *dst, uint32_t fn)
 {
+	uint8_t pl_len;
 	/* FIXME: add EFR support */
 	if (lchan->tch_mode == GSM48_CMODE_SPEECH_EFR)
 		return 0;
@@ -472,11 +473,54 @@ uint8_t repeat_last_sid(struct gsm_lchan *lchan, uint8_t *dst, uint32_t fn)
 	if (lchan->tch_mode != GSM48_CMODE_SPEECH_AMR) {
 		if (dtx_sched_optional(lchan, fn))
 			return 0;
-	} else
+		else {
+			if (lchan->ts->trx->bts->dtxd) {
+				/* Need to send zeroed TCH frame on mandatory Fn defined in GSM 05.08, section 8.3 */
+				switch (lchan->type) {
+				case GSM_LCHAN_TCH_F:
+					pl_len = GSM_FR_BYTES;
+					break;
+				case GSM_LCHAN_TCH_H:
+					pl_len = GSM_HR_BYTES;
+					break;
+				default:
+					return 0;
+				}
+				memcpy(dst, gsm_speech_zero, pl_len);
+
+				LOGP(DL1C, LOGL_DEBUG, "%s Have to send %s %s zero speech frame, Fn=%d, Fn mod 104=%d, dump=%s\n",
+									gsm_lchan_name(lchan),
+									get_value_string(gsm_chan_t_names, lchan->type),
+									get_value_string(gsm48_chan_mode_names, lchan->tch_mode),
+									fn,
+									fn%104,
+									osmo_hexdump(dst, pl_len));
+				return pl_len + 1;
+			}
+		}
+	} else {
+		if (!dtx_sched_optional(lchan, fn) && (lchan->rsl_cmode == RSL_CMOD_SPD_SPEECH)) {
+			if (!(lchan->tch.dtx.len)) {
+				pl_len = 9;
+				/* Send zero SID FIRST frame */
+				memcpy(dst, amr_sid_first_zero, pl_len);
+				LOGP(DL1C, LOGL_DEBUG, "%s Have to send %s %s zero speech frame, Fn=%d, Fn mod 104=%d, dump=%s\n",
+						gsm_lchan_name(lchan),
+						get_value_string(gsm_chan_t_names, lchan->type),
+						get_value_string(gsm48_chan_mode_names, lchan->tch_mode),
+						fn,
+						fn%104,
+						osmo_hexdump(dst, pl_len));
+				return pl_len + 1; /* plus one to take into account of payload type */
+			}
+		}
+
 		if (dtx_amr_sid_optional(lchan, fn))
 			return 0;
+	}
 
 	if (lchan->tch.dtx.len) {
+
 		if (dtx_dl_amr_enabled(lchan)) {
 			if ((lchan->type == GSM_LCHAN_TCH_H &&
 			     lchan->tch.dtx.dl_amr_fsm->state == ST_SID_F2) ||
@@ -502,11 +546,17 @@ uint8_t repeat_last_sid(struct gsm_lchan *lchan, uint8_t *dst, uint32_t fn)
 		}
 		memcpy(dst, lchan->tch.dtx.cache, lchan->tch.dtx.len);
 		lchan->tch.dtx.fn = fn;
+		LOGP(DL1C, LOGL_DEBUG, "%s Have to send %s SID buffer "
+			     "%s\n",
+				 gsm_lchan_name(lchan),
+			     get_value_string(gsm48_chan_mode_names, lchan->tch_mode),
+				 osmo_hexdump(lchan->tch.dtx.cache, lchan->tch.dtx.len));
 		return lchan->tch.dtx.len + 1;
 	}
 
-	LOGP(DL1C, LOGL_DEBUG, "Have to send %s frame on TCH but SID buffer "
+	LOGP(DL1C, LOGL_DEBUG, "%s Have to send %s frame on TCH but SID buffer "
 	     "is empty - sent nothing\n",
+		 gsm_lchan_name(lchan),
 	     get_value_string(gsm48_chan_mode_names, lchan->tch_mode));
 
 	return 0;

src/osmo-bts-litecell15/l1_if.c

@@ -332,6 +332,49 @@ empty_req_from_l1sap(GsmL1_Prim_t *l1p, struct lc15l1_hdl *fl1,
 	return empty_req;
 }
 
+/* fill frame PH-DATA.req from l1sap primitive */
+static GsmL1_PhDataReq_t *
+fill_req_from_l1sap(GsmL1_Prim_t *l1p, struct lc15l1_hdl *fl1,
+		uint8_t tn, uint32_t fn, uint8_t sapi, uint8_t sub_ch,
+		uint8_t block_nr)
+{
+	GsmL1_PhDataReq_t *data_req = &l1p->u.phDataReq;
+	GsmL1_MsgUnitParam_t *msu_param;
+	uint8_t *l1_payload;
+
+	msu_param = &data_req->msgUnitParam;
+	l1_payload = &msu_param->u8Buffer[0];
+	l1p->id = GsmL1_PrimId_PhDataReq;
+
+	memset(l1_payload, 0x2B, GSM_MACBLOCK_LEN);
+	/* address field */
+	l1_payload[0] = 0x03;
+	/* control field */
+	l1_payload[1] = 0x03;
+	/* length field */
+	l1_payload[2] = 0x01;
+
+	/* copy fields from PH-RTS.ind */
+	data_req->hLayer1	= (HANDLE)fl1->hLayer1;
+	data_req->u8Tn 		= tn;
+	data_req->u32Fn		= fn;
+	data_req->sapi		= sapi;
+	data_req->subCh		= sub_ch;
+	data_req->u8BlockNbr	= block_nr;
+	data_req->msgUnitParam.u8Size = GSM_MACBLOCK_LEN;
+
+
+	LOGP(DL1C, LOGL_DEBUG, "Send fill frame on in none DTX mode Tn=%d, Fn=%d, SAPI=%d, SubCh=%d, BlockNr=%d dump=%s\n",
+			tn,
+			fn,
+			sapi,
+			sub_ch,
+			block_nr,
+			osmo_hexdump(data_req->msgUnitParam.u8Buffer, data_req->msgUnitParam.u8Size));
+
+	return data_req;
+}
+
 static int ph_data_req(struct gsm_bts_trx *trx, struct msgb *msg,
 		       struct osmo_phsap_prim *l1sap, bool use_cache)
 {
@@ -462,10 +505,19 @@ static int ph_data_req(struct gsm_bts_trx *trx, struct msgb *msg,
 		     osmo_hexdump(l1p->u.phDataReq.msgUnitParam.u8Buffer,
 					  l1p->u.phDataReq.msgUnitParam.u8Size));
 	} else {
-		/* empty frame */
-		GsmL1_Prim_t *l1p = msgb_l1prim(l1msg);
 
-		empty_req_from_l1sap(l1p, fl1, u8Tn, u32Fn, sapi, subCh, u8BlockNbr);
+		GsmL1_Prim_t *l1p = msgb_l1prim(l1msg);
+		if (lchan->rsl_cmode == RSL_CMOD_SPD_SIGN)
+			/* fill frame */
+			fill_req_from_l1sap(l1p, fl1, u8Tn, u32Fn, sapi, subCh, u8BlockNbr);
+		else {
+			if (lchan->ts->trx->bts->dtxd)
+				/* empty frame */
+				empty_req_from_l1sap(l1p, fl1, u8Tn, u32Fn, sapi, subCh, u8BlockNbr);
+			else
+				/* fill frame */
+				fill_req_from_l1sap(l1p, fl1, u8Tn, u32Fn, sapi, subCh, u8BlockNbr);
+		}
 	}
 
 	/* send message to DSP's queue */