Modify EGPRS DL TBF flow to support SPB

Modify the EGPRS DL TBF flow to support Split block during
Retx. This patch will also Upgrade the test suite with test cases
to validate the EGPRS Downlink SPB for Retransmission

Scenarios like MCS6->MCS3, MCS4->MCS1, MCS5->MCS2, MCS9->MCS3
MCS7->MCS2, MCS8->MCS3 have been simulated and Integration tested
in NuRAN 1.0 hardware thoroughly.

Change-Id: I242afdd8ae7622dec8593b26382ad66bad5b9516

1 files changed, 235 insertions, 0 deletions

diff --git a/tests/tbf/TbfTest.cpp b/tests/tbf/TbfTest.cpp
index 90253b05..5e45506d 100644
--- a/tests/tbf/TbfTest.cpp
+++ b/tests/tbf/TbfTest.cpp
@@ -1814,6 +1814,203 @@ static void tbf_cleanup(gprs_rlcmac_dl_tbf *dl_tbf)
 
 }
 
+static void egprs_spb_to_normal_validation(BTS *the_bts,
+		int mcs, int demanded_mcs)
+{
+	uint32_t fn = 0;
+	gprs_rlcmac_dl_tbf *dl_tbf;
+	uint8_t block_nr = 0;
+	int index1 = 0;
+	uint8_t bn;
+	uint16_t bsn1, bsn2, bsn3;
+	struct msgb *msg;
+	struct gprs_rlc_dl_header_egprs_3 *egprs3;
+	struct gprs_rlc_dl_header_egprs_2 *egprs2;
+
+	printf("Testing retx for MCS %d to reseg_mcs %d\n", mcs, demanded_mcs);
+
+	dl_tbf = tbf_init(the_bts, mcs);
+
+	/*
+	 * Table 10.4.8a.3.1 of 44.060.
+	 * (MCS7, MCS9) to (MCS2, MCS3) is not handled since it is same as
+	 * (MCS5, MCS6) to (MCS2, MCS3) transition
+	 */
+	if (!(mcs == 6 && demanded_mcs == 3))
+		return;
+
+	fn = fn_add_blocks(fn, 1);
+	/* Send first RLC data block BSN 0 */
+	msg = dl_tbf->create_dl_acked_block(fn, dl_tbf->control_ts);
+	OSMO_ASSERT(dl_tbf->m_window.m_v_b.is_unacked(0));
+	OSMO_ASSERT(dl_tbf->m_rlc.block(0)->cs_current_trans.to_num()
+			== mcs);
+
+	egprs2 = (struct gprs_rlc_dl_header_egprs_2 *) msg->data;
+	bsn1 = (egprs2->bsn1_hi << 9) || (egprs2->bsn1_mid << 1)
+			|| (egprs2->bsn1_lo);
+	dl_tbf->m_window.m_v_b.mark_nacked(0);
+	OSMO_ASSERT(dl_tbf->m_window.m_v_b.is_nacked(0));
+	OSMO_ASSERT(bsn1 == 0);
+
+	dl_tbf->ms()->set_current_cs_dl
+		(static_cast < GprsCodingScheme::Scheme >
+			(GprsCodingScheme::CS4 + demanded_mcs));
+
+	fn = fn_add_blocks(fn, 1);
+
+	/* Send first segment with demanded_mcs */
+	msg = dl_tbf->create_dl_acked_block(fn, dl_tbf->control_ts);
+	OSMO_ASSERT(dl_tbf->m_window.m_v_b.is_nacked(0));
+	OSMO_ASSERT(dl_tbf->m_rlc.block(0)->cs_current_trans.to_num()
+			== demanded_mcs);
+	OSMO_ASSERT(dl_tbf->m_rlc.block(0)->spb_status.block_status_dl
+			== EGPRS_RESEG_FIRST_SEG_SENT);
+
+	egprs3 = (struct gprs_rlc_dl_header_egprs_3 *) msg->data;
+	OSMO_ASSERT(egprs3->spb == 2);
+
+	/* Table 10.4.8a.3.1 of 44.060 */
+	OSMO_ASSERT(egprs3->cps == 3);
+
+	/* Send second segment with demanded_mcs */
+	msg = dl_tbf->create_dl_acked_block(fn, dl_tbf->control_ts);
+	OSMO_ASSERT(dl_tbf->m_window.m_v_b.is_unacked(0));
+	OSMO_ASSERT(dl_tbf->m_rlc.block(0)->cs_current_trans.to_num()
+			== demanded_mcs);
+	OSMO_ASSERT(dl_tbf->m_rlc.block(0)->spb_status.block_status_dl
+			== EGPRS_RESEG_SECOND_SEG_SENT);
+
+	egprs3 = (struct gprs_rlc_dl_header_egprs_3 *) msg->data;
+	/* Table 10.4.8a.3.1 of 44.060 */
+	OSMO_ASSERT(egprs3->spb == 3);
+	bsn2 = (egprs3->bsn1_hi << 9) || (egprs3->bsn1_mid << 1) ||
+			(egprs3->bsn1_lo);
+	OSMO_ASSERT(bsn2 == bsn1);
+
+	/* Table 10.4.8a.3.1 of 44.060 */
+	OSMO_ASSERT(egprs3->cps == 3);
+
+	/* Handle (MCS3, MCS3) -> MCS6 case */
+	dl_tbf->ms()->set_current_cs_dl
+		(static_cast < GprsCodingScheme::Scheme >
+			(GprsCodingScheme::CS4 + mcs));
+
+	dl_tbf->m_window.m_v_b.mark_nacked(0);
+	OSMO_ASSERT(dl_tbf->m_window.m_v_b.is_nacked(0));
+	msg = dl_tbf->create_dl_acked_block(fn, dl_tbf->control_ts);
+	egprs2 = (struct gprs_rlc_dl_header_egprs_2 *) msg->data;
+
+	/* Table 10.4.8a.3.1 of 44.060 */
+	OSMO_ASSERT(egprs2->cps == 0);
+	bsn3 = (egprs2->bsn1_hi << 9) || (egprs2->bsn1_mid << 1) ||
+			(egprs2->bsn1_lo);
+	OSMO_ASSERT(bsn3 == bsn2);
+
+	tbf_cleanup(dl_tbf);
+}
+static void establish_and_use_egprs_dl_tbf_for_spb(BTS *the_bts,
+		int mcs, int demanded_mcs)
+{
+	uint32_t fn = 0;
+	gprs_rlcmac_dl_tbf *dl_tbf;
+	uint8_t block_nr = 0;
+	int index1 = 0;
+	uint8_t bn;
+	struct msgb *msg;
+	struct gprs_rlc_dl_header_egprs_3 *egprs3;
+
+	printf("Testing retx for MCS %d to reseg_mcs %d\n", mcs, demanded_mcs);
+
+	dl_tbf = tbf_init(the_bts, mcs);
+
+	/*
+	 * Table 10.4.8a.3.1 of 44.060.
+	 * (MCS7, MCS9) to (MCS2, MCS3) is not handled since it is same as
+	 * (MCS5, MCS6) to (MCS2, MCS3) transition
+	 */
+	/* TODO: Need to support of MCS8 -> MCS6 ->MCS3 transistion
+	 * Refer commit be881c028fc4da00c4046ecd9296727975c206a3
+	 * dated 2016-02-07 23:45:40 (UTC)
+	 */
+	if (!(((mcs == 5) && (demanded_mcs == 2)) ||
+		((mcs == 6) && (demanded_mcs == 3)) ||
+		((mcs == 4) && (demanded_mcs == 1))))
+		return;
+
+	fn = fn_add_blocks(fn, 1);
+	/* Send first RLC data block BSN 0 */
+	msg = dl_tbf->create_dl_acked_block(fn, dl_tbf->control_ts);
+	OSMO_ASSERT(dl_tbf->m_window.m_v_b.is_unacked(0));
+	OSMO_ASSERT(dl_tbf->m_rlc.block(0)->cs_current_trans.to_num()
+			== mcs);
+
+	dl_tbf->m_window.m_v_b.mark_nacked(0);
+	OSMO_ASSERT(dl_tbf->m_window.m_v_b.is_nacked(0));
+
+	dl_tbf->ms()->set_current_cs_dl
+		(static_cast < GprsCodingScheme::Scheme >
+			(GprsCodingScheme::CS4 + demanded_mcs));
+
+	fn = fn_add_blocks(fn, 1);
+
+	/* Send first segment with demanded_mcs */
+	msg = dl_tbf->create_dl_acked_block(fn, dl_tbf->control_ts);
+	OSMO_ASSERT(dl_tbf->m_window.m_v_b.is_nacked(0));
+	OSMO_ASSERT(dl_tbf->m_rlc.block(0)->cs_current_trans.to_num()
+			== demanded_mcs);
+	OSMO_ASSERT(dl_tbf->m_rlc.block(0)->spb_status.block_status_dl
+			== EGPRS_RESEG_FIRST_SEG_SENT);
+
+	egprs3 = (struct gprs_rlc_dl_header_egprs_3 *) msg->data;
+	OSMO_ASSERT(egprs3->spb == 2);
+
+	/* Table 10.4.8a.3.1 of 44.060 */
+	switch (demanded_mcs) {
+	case 3:
+		OSMO_ASSERT(egprs3->cps == 3);
+		break;
+	case 2:
+		OSMO_ASSERT(egprs3->cps == 9);
+		break;
+	case 1:
+		OSMO_ASSERT(egprs3->cps == 11);
+		break;
+	default:
+		OSMO_ASSERT(false);
+		break;
+	}
+
+	/* Send second segment with demanded_mcs */
+	msg = dl_tbf->create_dl_acked_block(fn, dl_tbf->control_ts);
+	OSMO_ASSERT(dl_tbf->m_window.m_v_b.is_unacked(0));
+	OSMO_ASSERT(dl_tbf->m_rlc.block(0)->cs_current_trans.to_num()
+			== demanded_mcs);
+	OSMO_ASSERT(dl_tbf->m_rlc.block(0)->spb_status.block_status_dl
+			== EGPRS_RESEG_SECOND_SEG_SENT);
+
+	egprs3 = (struct gprs_rlc_dl_header_egprs_3 *) msg->data;
+	/* Table 10.4.8a.3.1 of 44.060 */
+	OSMO_ASSERT(egprs3->spb == 3);
+
+	/* Table 10.4.8a.3.1 of 44.060 */
+	switch (demanded_mcs) {
+	case 3:
+		OSMO_ASSERT(egprs3->cps == 3);
+		break;
+	case 2:
+		OSMO_ASSERT(egprs3->cps == 9);
+		break;
+	case 1:
+		OSMO_ASSERT(egprs3->cps == 11);
+		break;
+	default:
+		OSMO_ASSERT(false);
+		break;
+	}
+	tbf_cleanup(dl_tbf);
+}
+
 static void establish_and_use_egprs_dl_tbf_for_retx(BTS *the_bts,
 		int mcs, int demanded_mcs)
 {
@@ -1972,6 +2169,9 @@ static void test_tbf_egprs_retx_dl(void)
 	setup_bts(&the_bts, ts_no);
 	bts->dl_tbf_idle_msec = 200;
 	bts->egprs_enabled = 1;
+	/* ARQ II */
+	bts->dl_arq_type = EGPRS_ARQ2;
+
 
 	/* First parameter is current MCS, second one is demanded_mcs */
 	establish_and_use_egprs_dl_tbf_for_retx(&the_bts, 6, 6);
@@ -1985,6 +2185,38 @@ static void test_tbf_egprs_retx_dl(void)
 	printf("=== end %s ===\n", __func__);
 }
 
+static void test_tbf_egprs_spb_dl(void)
+{
+	BTS the_bts;
+	gprs_rlcmac_bts *bts;
+	uint8_t ts_no = 4;
+	int i, j;
+
+	printf("=== start %s ===\n", __func__);
+
+	bts = the_bts.bts_data();
+	bts->cs_downgrade_threshold = 0;
+	setup_bts(&the_bts, ts_no);
+	bts->dl_tbf_idle_msec = 200;
+	bts->egprs_enabled = 1;
+
+	/* ARQ I resegmentation support */
+	bts->dl_arq_type = EGPRS_ARQ1;
+
+	/*
+	 * First parameter is current MCS, second one is demanded_mcs
+	 * currently only MCS5->MCS2, MCS6->3, MCS4->MCS1 is tested in UT
+	 * rest scenarios has been integration tested
+	 */
+	establish_and_use_egprs_dl_tbf_for_spb(&the_bts, 6, 3);
+	establish_and_use_egprs_dl_tbf_for_spb(&the_bts, 5, 2);
+	establish_and_use_egprs_dl_tbf_for_spb(&the_bts, 4, 1);
+	/* check MCS6->(MCS3+MCS3)->MCS6 case */
+	egprs_spb_to_normal_validation(&the_bts, 6, 3);
+
+	printf("=== end %s ===\n", __func__);
+}
+
 static void test_tbf_egprs_dl()
 {
 	BTS the_bts;
@@ -1999,6 +2231,8 @@ static void test_tbf_egprs_dl()
 	setup_bts(&the_bts, ts_no);
 	bts->dl_tbf_idle_msec = 200;
 	bts->egprs_enabled = 1;
+	/* ARQ II */
+	bts->dl_arq_type = EGPRS_ARQ2;
 
 	for (i = 1; i <= 9; i++)
 		establish_and_use_egprs_dl_tbf(&the_bts, i);
@@ -2071,6 +2305,7 @@ int main(int argc, char **argv)
 	test_tbf_egprs_two_phase_spb();
 	test_tbf_egprs_dl();
 	test_tbf_egprs_retx_dl();
+	test_tbf_egprs_spb_dl();
 
 	if (getenv("TALLOC_REPORT_FULL"))
 		talloc_report_full(tall_pcu_ctx, stderr);