edge: Get EGPRS multislot class

The EGPRS MS class ist contained in the MS_RA_capability information.
Its presence indicates, that the MS is able (and willing) to use
EGPRS.

This commit implements basic support for retrieving, storing, and
showing it in the VTY. The information is stored in the MS object.

Sponsored-by: On-Waves ehf

src/bts.cpp

@@ -990,6 +990,7 @@ void gprs_rlcmac_pdch::rcv_resource_request(Packet_Resource_Request_t *request,
 		struct gprs_rlcmac_dl_tbf *dl_tbf = NULL;
 		uint32_t tlli = request->ID.u.TLLI;
 		uint8_t ms_class = 0;
+		uint8_t egprs_ms_class = 0;
 		uint8_t ta = 0;
 		struct pcu_l1_meas meas;
 
@@ -1039,10 +1040,19 @@ void gprs_rlcmac_pdch::rcv_resource_request(Packet_Resource_Request_t *request,
 			ta = sba->ta;
 			bts()->sba()->free_sba(sba);
 		}
-		if (request->Exist_MS_Radio_Access_capability)
-			ms_class = Decoding::get_ms_class_by_capability(&request->MS_Radio_Access_capability);
+		if (request->Exist_MS_Radio_Access_capability) {
+			ms_class = Decoding::get_ms_class_by_capability(
+				&request->MS_Radio_Access_capability);
+			egprs_ms_class =
+				Decoding::get_egprs_ms_class_by_capability(
+					&request->MS_Radio_Access_capability);
+		}
 		if (!ms_class)
 			LOGP(DRLCMAC, LOGL_NOTICE, "MS does not give us a class.\n");
+		if (egprs_ms_class)
+			LOGP(DRLCMAC, LOGL_NOTICE,
+				"MS supports EGPRS multislot class %d.\n",
+				egprs_ms_class);
 		ul_tbf = tbf_alloc_ul(bts_data(), trx_no(), ms_class, tlli, ta, ms);
 		if (!ul_tbf)
 			return;
@@ -1053,6 +1063,10 @@ void gprs_rlcmac_pdch::rcv_resource_request(Packet_Resource_Request_t *request,
 		/* schedule uplink assignment */
 		ul_tbf->ul_ass_state = GPRS_RLCMAC_UL_ASS_SEND_ASS;
 
+		/* get capabilities */
+		if (ul_tbf->ms())
+			ul_tbf->ms()->set_egprs_ms_class(egprs_ms_class);
+
 		/* get measurements */
 		if (ul_tbf->ms()) {
 			get_meas(&meas, request);

src/decoding.cpp

@@ -83,6 +83,21 @@ uint8_t Decoding::get_ms_class_by_capability(MS_Radio_Access_capability_t *cap)
 	return 0;
 }
 
+uint8_t Decoding::get_egprs_ms_class_by_capability(MS_Radio_Access_capability_t *cap)
+{
+	int i;
+
+	for (i = 0; i < cap->Count_MS_RA_capability_value; i++) {
+		if (!cap->MS_RA_capability_value[i].u.Content.Exist_Multislot_capability)
+			continue;
+		if (!cap->MS_RA_capability_value[i].u.Content.Multislot_capability.Exist_EGPRS_multislot_class)
+			continue;
+		return cap->MS_RA_capability_value[i].u.Content.Multislot_capability.EGPRS_multislot_class;
+	}
+
+	return 0;
+}
+
 /**
  * show_rbb needs to be an array with 65 elements
  * The index of the array is the bit position in the rbb

src/decoding.h

@@ -28,6 +28,7 @@ public:
 	static int tlli_from_ul_data(const uint8_t *data, uint8_t len,
 					uint32_t *tlli);
 	static uint8_t get_ms_class_by_capability(MS_Radio_Access_capability_t *cap);
+	static uint8_t get_egprs_ms_class_by_capability(MS_Radio_Access_capability_t *cap);
 
 	static void extract_rbb(const uint8_t *rbb, char *extracted_rbb);
 };

src/gprs_ms.cpp

@@ -96,6 +96,7 @@ GprsMs::GprsMs(BTS *bts, uint32_t tlli) :
 	m_new_dl_tlli(0),
 	m_ta(0),
 	m_ms_class(0),
+	m_egprs_ms_class(0),
 	m_current_cs_ul(1),
 	m_current_cs_dl(1),
 	m_is_idle(true),
@@ -447,6 +448,18 @@ void GprsMs::set_ms_class(uint8_t ms_class_)
 	m_ms_class = ms_class_;
 }
 
+void GprsMs::set_egprs_ms_class(uint8_t ms_class_)
+{
+	if (ms_class_ == m_egprs_ms_class)
+		return;
+
+	LOGP(DRLCMAC, LOGL_INFO,
+		"Modifying MS object, TLLI = 0x%08x, EGPRS MS class %d -> %d\n",
+		tlli(), m_egprs_ms_class, ms_class_);
+
+	m_egprs_ms_class = ms_class_;
+}
+
 void GprsMs::update_error_rate(gprs_rlcmac_tbf *tbf, int error_rate)
 {
 	struct gprs_rlcmac_bts *bts_data;

src/gprs_ms.h

@@ -81,7 +81,9 @@ public:
 	uint8_t ta() const;
 	void set_ta(uint8_t ta);
 	uint8_t ms_class() const;
+	uint8_t egprs_ms_class() const;
 	void set_ms_class(uint8_t ms_class);
+	void set_egprs_ms_class(uint8_t ms_class);
 
 	uint8_t current_cs_ul() const;
 	uint8_t current_cs_dl() const;
@@ -148,6 +150,7 @@ private:
 	char m_imsi[16];
 	uint8_t m_ta;
 	uint8_t m_ms_class;
+	uint8_t m_egprs_ms_class;
 	/* current coding scheme */
 	uint8_t m_current_cs_ul;
 	uint8_t m_current_cs_dl;
@@ -212,6 +215,11 @@ inline uint8_t GprsMs::ms_class() const
 	return m_ms_class;
 }
 
+inline uint8_t GprsMs::egprs_ms_class() const
+{
+	return m_egprs_ms_class;
+}
+
 inline uint8_t GprsMs::current_cs_ul() const
 {
 	return m_current_cs_ul;

src/pcu_vty_functions.cpp

@@ -70,6 +70,7 @@ static int show_ms(struct vty *vty, GprsMs *ms)
 	vty_out(vty, "  Coding scheme downlink: CS-%d%s", ms->current_cs_dl(),
 		VTY_NEWLINE);
 	vty_out(vty, "  MS class:               %d%s", ms->ms_class(), VTY_NEWLINE);
+	vty_out(vty, "  EGPRS MS class:         %d%s", ms->egprs_ms_class(), VTY_NEWLINE);
 	vty_out(vty, "  LLC queue length:       %d%s", ms->llc_queue()->size(),
 		VTY_NEWLINE);
 	vty_out(vty, "  LLC queue octets:       %d%s", ms->llc_queue()->octets(),