[L] Change in osmo-trx[master]: proxy: detect TSC of bursts relayed from TRXDv0/v1

20 Sep 2026

fixeria has submitted this change. ( https://gerrit.osmocom.org/c/osmo-trx/+/43629?usp=email )
(
2 is the latest approved patch-set.
No files were changed between the latest approved patch-set and the submitted one.
 )Change subject: proxy: detect TSC of bursts relayed from TRXDv0/v1
......................................................................
proxy: detect TSC of bursts relayed from TRXDv0/v1
A BURST.req sourced from TRXDv0/v1 carries no MTS field at all, so
the proxy has no way to know the true modulation/TSC of a burst it
forwards onward as a TRXDv1/TRXDv2 BURST.ind (whose MTS field is
mandatory).
Add burst_synch: detect the training/synch. sequence of a burst
by comparing known positions within it against the GMSK and 8-PSK
Normal Burst TSC sets (3GPP TS 45.002 tables 5.2.3a-d, 5.2.3f-g),
Access Burst (table 5.2.7-3) and Synchronization Burst (table 5.2.5-3)
sequences, mirroring fake_trx.py's TrainingSeqGMSK.pick().
burst_fwd.c calls this whenever the source BURST.req did not already
carry real TSC info, filling in mod/tsc_set/tsc (and
OSMO_TRXD_F_ACCESS_BURST for a detected Access Burst) before the
burst is relayed onward.
Change-Id: I686451bb80a0ebd7f522f58c910f2d0410305b7d
Related: OS#6672
---
M proxy/Makefile.am
A proxy/include/osmocom/proxy/burst_synch.h
M proxy/src/Makefile.am
M proxy/src/burst_fwd.c
A proxy/src/burst_synch.c
5 files changed, 356 insertions(+), 0 deletions(-)
Approvals:
  laforge: Looks good to me, but someone else must approve
  pespin: Looks good to me, approved
  Jenkins Builder: Verified

diff --git a/proxy/Makefile.am b/proxy/Makefile.am
index 909c698..d0eb6cf 100644
--- a/proxy/Makefile.am
+++ b/proxy/Makefile.am
@@ -3,6 +3,7 @@
    $(NULL)
noinst_HEADERS = \
+	include/osmocom/proxy/burst_synch.h \
    include/osmocom/proxy/clck_gen.h \
    include/osmocom/proxy/logging.h \
    include/osmocom/proxy/path_sim.h \
diff --git a/proxy/include/osmocom/proxy/burst_synch.h b/proxy/include/osmocom/proxy/burst_synch.h
new file mode 100644
index 0000000..4af221a
--- /dev/null
+++ b/proxy/include/osmocom/proxy/burst_synch.h
@@ -0,0 +1,7 @@
+#pragma once
+
+struct osmo_trxd_burst_ind;
+struct osmo_trxd_burst_req;
+
+void burst_synch_detect(struct osmo_trxd_burst_ind *bi,
+			const struct osmo_trxd_burst_req *br);
diff --git a/proxy/src/Makefile.am b/proxy/src/Makefile.am
index 4c3678e..ddd27b5 100644
--- a/proxy/src/Makefile.am
+++ b/proxy/src/Makefile.am
@@ -21,6 +21,7 @@
    clck_gen.c \
    ctrl_cmd.c \
    burst_fwd.c \
+	burst_synch.c \
    path_sim.c \
    logging.c \
    $(NULL)
diff --git a/proxy/src/burst_fwd.c b/proxy/src/burst_fwd.c
index de057b6..cc64743 100644
--- a/proxy/src/burst_fwd.c
+++ b/proxy/src/burst_fwd.c
@@ -33,6 +33,7 @@
 #include <osmocom/proxy/proxy.h>
 #include <osmocom/proxy/trx.h>
 #include <osmocom/proxy/path_sim.h>
+#include <osmocom/proxy/burst_synch.h>
 #include <osmocom/proxy/logging.h>
#define OSMO_TRXD_F_COMMON_MASK	( \
@@ -57,6 +58,12 @@
    	.trx_num = br->trx_num,
    };
+	/* TRXDv0/v1 BURST.req PDUs carry no MTS field at all, so the true
+	 * modulation/TSC of the burst is unknown here: detect it instead of
+	 * asserting a fixed, possibly wrong TSC downstream. */
+	if (~br->flags & OSMO_TRXD_F_TS_INFO)
+		burst_synch_detect(&bi, br);
+
    osmo_ubit2sbit(bi.burst, br->burst, br->burst_len);
    path_sim_apply(&bi, &dst->chans[dst_chan],
    	       br, &src->chans[src_chan],
diff --git a/proxy/src/burst_synch.c b/proxy/src/burst_synch.c
new file mode 100644
index 0000000..5ff67e0
--- /dev/null
+++ b/proxy/src/burst_synch.c
@@ -0,0 +1,340 @@
+/*! \file src/burst_synch.c
+ * osmo-trx-proxy: detect the training/synch. sequence of a burst. */
+
+/*
+ * (C) 2026 by sysmocom - s.f.m.c. GmbH info@sysmocom.de
+ * Author: Vadim Yanitskiy vyanitskiy@sysmocom.de
+ *
+ * All Rights Reserved
+ *
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see http://www.gnu.org/licenses/.
+ */
+
+#include <stdint.h>
+#include <string.h>
+
+#include <osmocom/core/bits.h>
+#include <osmocom/gsm/gsm0502.h>
+#include <osmocom/trx/trxd.h>
+
+#include <osmocom/proxy/burst_synch.h>
+
+/* A BURST.req sourced from TRXDv0/v1 carries no MTS field at all, so the
+ * proxy has no way to know the true modulation/TSC of a burst it forwards
+ * onward as a TRXDv1/TRXDv2 BURST.ind (whose MTS field is mandatory).
+ * Rather than asserting a fixed, possibly wrong TSC, detect it by
+ * comparing known positions within the burst against the following
+ * training/synch. sequences defined in 3GPP TS 45.002:
+ *
+ *   - Access Burst (RACH), table 5.2.7-3: TS0, TS1, TS2, TS4.
+ *     Table 5.2.7-4 (EC operation variants) is not covered, as EC
+ *     operation is not implemented by Osmocom.
+ *   - Synchronization Burst (SCH), table 5.2.5-3: TS0..TS3.
+ *   - Normal Burst (GMSK), tables 5.2.3a-d: all four TSC sets, TSC 0..7 each.
+ *   - Normal Burst (8-PSK), tables 5.2.3f-g: both TSC sets, TSC 0..7 each.
+ */
+
+#define AB_SEQ_NUM		4
+
+/* 3GPP TS 45.002, section 5.2.5, gives the Sync. Burst layout as
+ * tail(3) + encrypted(39) + train_seq(64) + encrypted(39) + tail(3). */
+#define SB_OFFSET		(GSM_NBITS_SB_GMSK_TAIL + GSM_NBITS_SB_GMSK_PAYLOAD / 2)
+#define SB_SEQ_NUM		4
+
+/* 3GPP TS 45.002, section 5.2.3, gives the Normal Burst (GMSK) layout as
+ * tail(3) + encrypted(58) + train_seq(26) + encrypted(58) + tail(3). */
+#define NB_OFFSET		(GSM_NBITS_NB_GMSK_TAIL + GSM_NBITS_NB_GMSK_PAYLOAD / 2)
+#define NB_TSC_SET_NUM		4
+#define NB_TSC_NUM		8
+
+/* 3GPP TS 45.002, section 5.2.3.3, gives the Normal Burst (8-PSK) layout as
+ * tail(9) + encrypted(174) + train_seq(78) + encrypted(174) + tail(9). */
+#define NB8_OFFSET		(GSM_NBITS_NB_8PSK_TAIL + GSM_NBITS_NB_8PSK_PAYLOAD / 2)
+#define NB8_TSC_SET_NUM		2
+#define NB8_TSC_NUM		8
+
+/* 3GPP TS 45.002, table 5.2.7-3: Access Burst synch. sequence bits.
+ * Indexed by TSC (0, 1, 2, 4 -- 3, 5, 6, 7 are EC-only, see table 5.2.7-4). */
+static const ubit_t ab_seq[AB_SEQ_NUM][GSM_NBITS_AB_GMSK_SYNCH_SEQ] = {
+	{ /* TSC 0 */
+		0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1,
+		1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0,
+	},
+	{ /* TSC 1 */
+		0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0,
+		0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1,
+	},
+	{ /* TSC 2 */
+		1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1,
+		0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1,
+	},
+	{ /* TSC 4 */
+		1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0,
+		0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0,
+	},
+};
+static const uint8_t ab_seq_tsc[AB_SEQ_NUM] = { 0, 1, 2, 4 };
+
+/* 3GPP TS 45.002, table 5.2.5-3: Synchronization Burst extended training
+ * sequence bits. Indexed by TSC (0..3). */
+static const ubit_t sb_seq[SB_SEQ_NUM][GSM_NBITS_SB_GMSK_ETRAIN_SEQ] = {
+	{ /* TSC 0 */
+		1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0,
+		0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1,
+		0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 1,
+		1, 0, 1, 1,
+	},
+	{ /* TSC 1 */
+		1, 1, 1, 0, 1, 1, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0,
+		1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0,
+		0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 0, 1,
+		0, 1, 0, 1,
+	},
+	{ /* TSC 2 */
+		1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1,
+		0, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0,
+		0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 0,
+		1, 1, 1, 0,
+	},
+	{ /* TSC 3 */
+		1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1,
+		0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1,
+		0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 0, 1,
+		1, 0, 0, 0,
+	},
+};
+
+/* 3GPP TS 45.002, tables 5.2.3a-d: Normal Burst training sequence bits.
+ * Indexed by [TSC set 0..3][TSC 0..7]. */
+static const ubit_t nb_seq[NB_TSC_SET_NUM][NB_TSC_NUM][GSM_NBITS_NB_GMSK_TRAIN_SEQ] = {
+	{ /* TSC set 1 */
+		{ 0, 0, 1, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1, 1, 1 }, /* TSC 0 */
+		{ 0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 1 }, /* TSC 1 */
+		{ 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0 }, /* TSC 2 */
+		{ 0, 1, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 0 }, /* TSC 3 */
+		{ 0, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 1, 1 }, /* TSC 4 */
+		{ 0, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 0 }, /* TSC 5 */
+		{ 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1 }, /* TSC 6 */
+		{ 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0 }, /* TSC 7 */
+	},
+	{ /* TSC set 2 */
+		{ 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1 }, /* TSC 0 */
+		{ 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 0, 0, 0, 1 }, /* TSC 1 */
+		{ 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0 }, /* TSC 2 */
+		{ 0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0 }, /* TSC 3 */
+		{ 0, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0 }, /* TSC 4 */
+		{ 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1 }, /* TSC 5 */
+		{ 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1 }, /* TSC 6 */
+		{ 0, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 1, 0, 0, 1 }, /* TSC 7 */
+	},
+	{ /* TSC set 3 */
+		{ 1, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0 }, /* TSC 0 */
+		{ 0, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0 }, /* TSC 1 */
+		{ 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0 }, /* TSC 2 */
+		{ 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0 }, /* TSC 3 */
+		{ 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0 }, /* TSC 4 */
+		{ 1, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0 }, /* TSC 5 */
+		{ 1, 0, 1, 1, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0 }, /* TSC 6 */
+		{ 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0 }, /* TSC 7 */
+	},
+	{ /* TSC set 4 */
+		{ 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0 }, /* TSC 0 */
+		{ 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 0 }, /* TSC 1 */
+		{ 1, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0 }, /* TSC 2 */
+		{ 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0 }, /* TSC 3 */
+		{ 1, 1, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0 }, /* TSC 4 */
+		{ 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 1, 0 }, /* TSC 5 */
+		{ 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, 0 }, /* TSC 6 */
+		{ 0, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0 }, /* TSC 7 */
+	},
+};
+
+/* 3GPP TS 45.002, tables 5.2.3f-g: Normal Burst (8-PSK) training sequence
+ * bits. Indexed by [TSC set 0..1][TSC 0..7]. */
+static const ubit_t nb8_seq[NB8_TSC_SET_NUM][NB8_TSC_NUM][GSM_NBITS_NB_8PSK_TRAIN_SEQ] = {
+	{ /* TSC set 1 */
+		{ /* TSC 0 */
+			1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1,
+			1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+			1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1,
+			1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1,
+		},
+		{ /* TSC 1 */
+			1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1,
+			1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0,
+			0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1,
+			0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1,
+		},
+		{ /* TSC 2 */
+			1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0,
+			1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1,
+			1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1,
+			1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1,
+		},
+		{ /* TSC 3 */
+			1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0,
+			1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0,
+			0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1,
+			1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1,
+		},
+		{ /* TSC 4 */
+			1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0,
+			1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0,
+			0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1,
+			0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1,
+		},
+		{ /* TSC 5 */
+			1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0,
+			1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1,
+			1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1,
+			0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1,
+		},
+		{ /* TSC 6 */
+			0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0,
+			1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1,
+			1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1,
+			1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1,
+		},
+		{ /* TSC 7 */
+			0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0,
+			1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1,
+			1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1,
+			0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1,
+		},
+	},
+	{ /* TSC set 2 */
+		{ /* TSC 0 */
+			1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1,
+			1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0,
+			0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1,
+			0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1,
+		},
+		{ /* TSC 1 */
+			1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0,
+			1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0,
+			0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1,
+			1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+		},
+		{ /* TSC 2 */
+			0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0,
+			1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0,
+			0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1,
+			1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1,
+		},
+		{ /* TSC 3 */
+			1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0,
+			1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0,
+			0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1,
+			1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1,
+		},
+		{ /* TSC 4 */
+			1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0,
+			1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1,
+			1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1,
+			1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1,
+		},
+		{ /* TSC 5 */
+			1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0,
+			1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1,
+			1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+			0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1,
+		},
+		{ /* TSC 6 */
+			0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0,
+			1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1,
+			1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1,
+			0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1,
+		},
+		{ /* TSC 7 */
+			0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0,
+			1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0,
+			0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1,
+			1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1,
+		},
+	},
+};
+
+static void burst_synch_detect_gmsk(struct osmo_trxd_burst_ind *bi,
+				    const struct osmo_trxd_burst_req *br)
+{
+	/* Normal Bursts are by far the most common: check them first */
+	for (unsigned int j = 0; j < NB_TSC_SET_NUM; j++) {
+		for (unsigned int k = 0; k < NB_TSC_NUM; k++) {
+			if (memcmp(&br->burst[NB_OFFSET], nb_seq[j][k],
+				   GSM_NBITS_NB_GMSK_TRAIN_SEQ) != 0)
+				continue;
+			bi->flags |= OSMO_TRXD_F_TS_INFO;
+			bi->tsc_set = j;
+			bi->tsc = k;
+			return;
+		}
+	}
+
+	for (unsigned int i = 0; i < AB_SEQ_NUM; i++) {
+		if (memcmp(&br->burst[GSM_NBITS_AB_GMSK_ETAIL], ab_seq[i],
+			   GSM_NBITS_AB_GMSK_SYNCH_SEQ) != 0)
+			continue;
+		bi->flags |= OSMO_TRXD_F_TS_INFO | OSMO_TRXD_F_ACCESS_BURST;
+		bi->tsc_set = 0;
+		bi->tsc = ab_seq_tsc[i];
+		return;
+	}
+
+	/* SCH only ever occurs on TS0 */
+	if (br->tn == 0) {
+		for (unsigned int i = 0; i < SB_SEQ_NUM; i++) {
+			if (memcmp(&br->burst[SB_OFFSET], sb_seq[i],
+				   GSM_NBITS_SB_GMSK_ETRAIN_SEQ) != 0)
+				continue;
+			bi->flags |= OSMO_TRXD_F_TS_INFO;
+			bi->tsc_set = 0;
+			bi->tsc = i;
+			return;
+		}
+	}
+}
+
+static void burst_synch_detect_8psk(struct osmo_trxd_burst_ind *bi,
+				    const struct osmo_trxd_burst_req *br)
+{
+	for (unsigned int j = 0; j < NB8_TSC_SET_NUM; j++) {
+		for (unsigned int k = 0; k < NB8_TSC_NUM; k++) {
+			if (memcmp(&br->burst[NB8_OFFSET], nb8_seq[j][k],
+				   GSM_NBITS_NB_8PSK_TRAIN_SEQ) != 0)
+				continue;
+			bi->flags |= OSMO_TRXD_F_TS_INFO;
+			bi->tsc_set = j;
+			bi->tsc = k;
+			return;
+		}
+	}
+}
+
+/*! Detect the training/synch. sequence used by the hard-bits of br and
+ * fill in bi->{mod,tsc_set,tsc} fields accordingly. */
+void burst_synch_detect(struct osmo_trxd_burst_ind *bi,
+			const struct osmo_trxd_burst_req *br)
+{
+	/* NOPE.req has no burst to correlate */
+	if (br->flags & OSMO_TRXD_F_NOPE_REQ)
+		return;
+
+	/* libosmo-trx's trxd_burst_req_parse_v01() sets br->mod for us */
+	if (br->mod == OSMO_TRXD_MOD_T_GMSK)
+		burst_synch_detect_gmsk(bi, br);
+	else if (br->mod == OSMO_TRXD_MOD_T_8PSK)
+		burst_synch_detect_8psk(bi, br);
+}
-- 
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Gerrit-MessageType: merged
Gerrit-Project: osmo-trx
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Gerrit-Change-Id: I686451bb80a0ebd7f522f58c910f2d0410305b7d
Gerrit-Change-Number: 43629
Gerrit-PatchSet: 5
Gerrit-Owner: fixeria vyanitskiy@sysmocom.de
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Gerrit-Reviewer: fixeria vyanitskiy@sysmocom.de
Gerrit-Reviewer: laforge laforge@osmocom.org
Gerrit-Reviewer: pespin pespin@sysmocom.de



    

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[L] Change in osmo-trx[master]: proxy: detect TSC of bursts relayed from TRXDv0/v1