vty: disallow combination of early-IA and frequency hopping

Related: osmo-bts Id9a930e5c67122812b229dc27ea2bfe246b67611
Related: SYS#6655
Change-Id: I8d375e5155be7b53034d5c0be5566d2f33af5db0
---
M src/osmo-bsc/bts_trx_vty.c
M src/osmo-bsc/bts_vty.c
A tests/early_ia.vty
3 files changed, 67 insertions(+), 3 deletions(-)

diff --git a/src/osmo-bsc/bts_trx_vty.c b/src/osmo-bsc/bts_trx_vty.c
index 385336b..9a58089 100644
--- a/src/osmo-bsc/bts_trx_vty.c
+++ b/src/osmo-bsc/bts_trx_vty.c
@@ -349,6 +349,13 @@
 		return CMD_WARNING;
 	}
 
+	if (enabled && bts->imm_ass_time != IMM_ASS_TIME_POST_CHAN_ACK) {
+		vty_out(vty,
+			"%% ERROR: 'hopping enabled 1' works only with 'immediate-assignment post-chan-ack'%s",
+			VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
 	ts->hopping.enabled = enabled;
 
 	return CMD_SUCCESS;
diff --git a/src/osmo-bsc/bts_vty.c b/src/osmo-bsc/bts_vty.c
index 54eb5cf..8b97dce 100644
--- a/src/osmo-bsc/bts_vty.c
+++ b/src/osmo-bsc/bts_vty.c
@@ -3242,13 +3242,35 @@
 	   CMD_ATTR_IMMEDIATE)
 {
 	struct gsm_bts *bts = vty->index;
+	enum imm_ass_time imm_ass_time;
 
 	if (!strcmp(argv[0], "pre-ts-ack"))
-		bts->imm_ass_time = IMM_ASS_TIME_PRE_TS_ACK;
+		imm_ass_time = IMM_ASS_TIME_PRE_TS_ACK;
 	else if (!strcmp(argv[0], "pre-chan-ack"))
-		bts->imm_ass_time = IMM_ASS_TIME_PRE_CHAN_ACK;
+		imm_ass_time = IMM_ASS_TIME_PRE_CHAN_ACK;
 	else
-		bts->imm_ass_time = IMM_ASS_TIME_POST_CHAN_ACK;
+		imm_ass_time = IMM_ASS_TIME_POST_CHAN_ACK;
+
+	if (imm_ass_time != IMM_ASS_TIME_POST_CHAN_ACK) {
+		struct gsm_bts_trx *trx;
+
+		/* Early-IA does not work with frequency hopping, because the IMM ASS does not convey an ARFCN when
+		 * frequency hopping is in use. Make sure the user knows that. */
+		llist_for_each_entry(trx, &bts->trx_list, list) {
+			int ts_nr;
+			for (ts_nr = 0; ts_nr < TRX_NR_TS; ts_nr++) {
+				struct gsm_bts_trx_ts *ts = &trx->ts[ts_nr];
+				if (ts->hopping.enabled) {
+					vty_out(vty, "%% ERROR: 'hopping enabled 1' works only with"
+						" 'immediate-assignment post-chan-ack', see timeslot %s%s",
+						ts->fi->id, VTY_NEWLINE);
+					return CMD_WARNING;
+				}
+			}
+		}
+	}
+
+	bts->imm_ass_time = imm_ass_time;
 	return CMD_SUCCESS;
 }
 
diff --git a/tests/early_ia.vty b/tests/early_ia.vty
new file mode 100644
index 0000000..4ba6b3a
--- /dev/null
+++ b/tests/early_ia.vty
@@ -0,0 +1,24 @@
+OsmoBSC> enable
+OsmoBSC# configure terminal
+OsmoBSC(config)# network
+OsmoBSC(config-net)# bts 0
+
+OsmoBSC(config-net-bts)# ### Check that first setting early-IA and then enabling frequency hopping throws an error
+OsmoBSC(config-net-bts)# immediate-assignment pre-chan-ack
+OsmoBSC(config-net-bts)# trx 0
+OsmoBSC(config-net-bts-trx)# timeslot 2
+OsmoBSC(config-net-bts-trx-ts)# hopping enabled 1
+% ERROR: 'hopping enabled 1' works only with 'immediate-assignment post-chan-ack'
+OsmoBSC(config-net-bts-trx-ts)# hopping enabled 0
+OsmoBSC(config-net-bts-trx-ts)# exit
+OsmoBSC(config-net-bts-trx)# exit
+OsmoBSC(config-net-bts)# immediate-assignment post-chan-ack
+
+OsmoBSC(config-net-bts)# ### Check that first enabling frequency hopping and then setting early-IA throws an error
+OsmoBSC(config-net-bts)# trx 0
+OsmoBSC(config-net-bts-trx)# timeslot 2
+OsmoBSC(config-net-bts-trx-ts)# hopping enabled 1
+OsmoBSC(config-net-bts-trx-ts)# exit
+OsmoBSC(config-net-bts-trx)# exit
+OsmoBSC(config-net-bts)# immediate-assignment pre-chan-ack
+% ERROR: 'hopping enabled 1' works only with 'immediate-assignment post-chan-ack', see timeslot 0-0-2-NONE

