From a3f0a85eb2dfb3cd37da84cb96a5b6a27fbf5951 Mon Sep 17 00:00:00 2001
From: Pau Espin Pedrol <pespin@sysmocom.de>
Date: Mon, 2 Dec 2019 19:16:26 +0100
Subject: [PATCH] pcu: TC_mo_ping_pong: Check DL block is sent and ACK it

Function f_rx_rlcmac_dl_block_exp_data() still misses proper
verification of data. Apparently the received message has 2 blocks,
first with expected 10 bytes, but next one contains 18 bytes with 4
actual bytes and other bits are padding.

Last DL ACK/NACK sent is not yet working correctly. osmo-pcu seems to be
unable to match it against sent DL block (I think due to non-matching
FN), and instead drops it and schedules after timeout an IMM ASS to try
to send DL block again.

Change-Id: Icf66dd5c07690368722c586632c38fb7e770053c
---
 library/RLCMAC_CSN1_Types.ttcn |  4 ++--
 library/RLCMAC_Types.ttcn      | 25 ++++++++++++++++++++++++-
 pcu/PCU_Tests_RAW.ttcn         | 32 +++++++++++++++++++++++++++++---
 3 files changed, 55 insertions(+), 6 deletions(-)

diff --git a/library/RLCMAC_CSN1_Types.ttcn b/library/RLCMAC_CSN1_Types.ttcn
index 29ec07b9b..a2f9a92dc 100644
--- a/library/RLCMAC_CSN1_Types.ttcn
+++ b/library/RLCMAC_CSN1_Types.ttcn
@@ -643,11 +643,11 @@ module RLCMAC_CSN1_Types {
 		}
 	}
 
-	private const ILevel iNone := {
+	const ILevel iNone := {
 		presence := '0'B,
 		i_level := omit
 	}
-	private const ChannelQualityReport c_ChQualRep_default := {
+	const ChannelQualityReport c_ChQualRep_default := {
 		c_value := 0,
 		rxqual := 0,
 		sign_var := 0,
diff --git a/library/RLCMAC_Types.ttcn b/library/RLCMAC_Types.ttcn
index b0dac35be..8e6942e61 100644
--- a/library/RLCMAC_Types.ttcn
+++ b/library/RLCMAC_Types.ttcn
@@ -256,7 +256,30 @@ module RLCMAC_Types {
 		}
 	}
 
-	/* Template fro uplink Data block */
+	/* Send Template for Downlink ACK/NACK */
+	template RlcmacUlBlock ts_RLCMAC_DL_ACK_NACK(template uint5_t tfi, AckNackDescription andesc, boolean retry := false) := {
+		ctrl := {
+			mac_hdr := {
+				payload_type := MAC_PT_RLCMAC_NO_OPT,
+				spare := '00000'B,
+				retry := retry
+			},
+			payload := {
+				msg_type := PACKET_DL_ACK_NACK,
+				u := {
+					dl_ack_nack := {
+						dl_tfi := tfi,
+						ack_nack_desc := andesc,
+						chreq_desc_presence := '0'B,
+						chreq_desc := omit,
+						ch_qual_rep := c_ChQualRep_default
+					}
+				}
+			}
+		}
+	}
+
+	/* Template for uplink Data block */
 	template RlcmacUlBlock t_RLCMAC_UL_DATA(template uint5_t tfi, template uint4_t cv, template uint7_t bsn,
 						template LlcBlocks blocks := {}, template boolean stall := false) := {
 		data := {
diff --git a/pcu/PCU_Tests_RAW.ttcn b/pcu/PCU_Tests_RAW.ttcn
index 4a6f54aa0..410dc31c9 100644
--- a/pcu/PCU_Tests_RAW.ttcn
+++ b/pcu/PCU_Tests_RAW.ttcn
@@ -46,6 +46,8 @@ import from PCU_Tests all;
 
 modulepar {
 	charstring mp_pcu_sock_path := PCU_SOCK_DEFAULT;
+
+	float X2002 := 0.2; /* Timer -2002, IMM ASSIGN confirm delay */
 }
 
 type component RAW_NS_CT {
@@ -753,6 +755,19 @@ runs on RAW_PCU_Test_CT {
 	}
 }
 
+private function f_rx_rlcmac_dl_block_exp_data(out RlcmacDlBlock dl_block, octetstring data)
+runs on RAW_PCU_Test_CT {
+	var template RlcmacDlBlock dl_template := tr_RLCMAC_DATA_RRBP;
+	dl_template.data.blocks := ?;
+	/* TODO: match data correctly: { valueof(t_RLCMAC_LLCBLOCK(data)) }; */
+
+	f_rx_rlcmac_dl_block(dl_block);
+	if (not match(dl_block, dl_template)) {
+		setverdict(fail, "Failed to match Packet data: ", dl_block, " vs ", dl_template);
+		mtc.stop;
+	}
+}
+
 testcase TC_pcuif_suspend() runs on RAW_PCU_Test_CT {
 	var octetstring ra_id := enc_RoutingAreaIdentification(mp_gb_cfg.cell_id.ra_id);
 	var GprsTlli tlli := 'FFFFFFFF'O;
@@ -1320,9 +1335,15 @@ testcase TC_mo_ping_pong() runs on RAW_PCU_Test_CT {
 	var PacketDlAssign dl_tbf_ass;
 	var RlcmacDlBlock dl_block;
 	var PCUIF_Message pcu_msg;
-	var octetstring data;
+	var octetstring data := f_rnd_octstring(10);
 	var boolean ok;
 	var OCT4 tlli := '00000001'O;
+	var AckNackDescription ack_nack_desc;
+
+	ack_nack_desc.final_ack := '0'B;
+	ack_nack_desc.starting_seq_nr := 0;
+	ack_nack_desc.receive_block_bitmap := '0000000000000000000000000000000000000000000000000000000000000000'B;
+
 
 	/* Initialize NS/BSSGP side */
 	f_init_bssgp();
@@ -1354,7 +1375,7 @@ testcase TC_mo_ping_pong() runs on RAW_PCU_Test_CT {
 	BSSGP[0].receive(tr_BSSGP_UL_UD(tlli, mp_gb_cfg.cell_id));
 
 	/* Now SGSN sends some DL data, PCU will page on CCCH (PCH) */
-	BSSGP[0].send(ts_BSSGP_DL_UD(tlli, f_rnd_octstring(10)));
+	BSSGP[0].send(ts_BSSGP_DL_UD(tlli, data));
 	f_pcuif_rx_pch_imm_tbf_ass(rr_imm_ass);
 
 	ok := f_imm_ass_verify_dl_tbf_ass(rr_imm_ass, dl_tbf_ass);
@@ -1363,7 +1384,12 @@ testcase TC_mo_ping_pong() runs on RAW_PCU_Test_CT {
 		mtc.stop;
 	}
 
-	/* TODO: ACK the assignment and the DL block somehow? */
+	/* Wait timer X2002 and DL block is available after CCCH IMM ASS: */
+	f_sleep(X2002);
+	f_rx_rlcmac_dl_block_exp_data(dl_block, data);
+
+	/* ACK the DL block */
+	f_tx_rlcmac_ul_block(ts_RLCMAC_DL_ACK_NACK(dl_block.data.mac_hdr.hdr_ext.tfi, ack_nack_desc));
 }
 
 control {