BTS_Tests: add new testcase TC_pcu_data_req_imm_ass_agch

In PCUIF v.11 we support getting confirmations for IMMEDIATE ASSIGNMENT
messages that are sent through the AGCH.

Related: OS#5927
Change-Id: Iec00d8144dfb2cd8bcee9093c96a3cc98aea6458
diff --git a/bts/BTS_Tests.ttcn b/bts/BTS_Tests.ttcn
index 317ed70..1b43797 100644
--- a/bts/BTS_Tests.ttcn
+++ b/bts/BTS_Tests.ttcn
@@ -5866,6 +5866,30 @@
 	}
 }
 
+/* Send IMM.ASS from PCU for AGCH; check it appears on Um side */
+testcase TC_pcu_data_req_imm_ass_agch() runs on test_CT {
+	var octetstring req_ref := f_rnd_octstring(3);
+	var octetstring tlli := f_rnd_octstring(4);
+	var octetstring imm_ass := '2d063f300fc364'O & req_ref & '0000dc'O & tlli & '00232b2b2b2b'O;
+	f_init_with_pcuif();
+	f_init_l1ctl();
+	f_l1_tune(L1CTL);
+
+	f_PCUIF_tx_mac_block_agch(PCU, g_pcu_conn_id, imm_ass);
+
+	timer T := 0.5;
+	T.start;
+	alt {
+	[] L1CTL.receive(tr_L1CTL_DATA_IND(t_RslChanNr_PCH_AGCH(0), ?, imm_ass)) {
+		setverdict(pass);
+		}
+	[] L1CTL.receive { repeat; }
+	[] T.timeout {
+		Misc_Helpers.f_shutdown(__BFILE__, __LINE__, fail, "Timeout waiting for PCU-originated AGCH block on Um");
+		}
+	}
+}
+
 /* Send RACH from Um side, expect it to show up on PCU socket */
 testcase TC_pcu_rach_content() runs on test_CT {
 	f_init_with_pcuif();
@@ -9076,6 +9100,7 @@
 		execute( TC_pcu_data_req_agch() );
 		execute( TC_pcu_data_req_pch() );
 		execute( TC_pcu_data_req_imm_ass_pch() );
+		execute( TC_pcu_data_req_imm_ass_agch() );
 		execute( TC_pcu_rach_content() );
 		execute( TC_pcu_ext_rach_content() );
 		execute( TC_pcu_data_ind_lqual_cb() );