From 041411cb706249f0aafcda250e4a744b00f0de30 Mon Sep 17 00:00:00 2001 From: Vadim Yanitskiy Date: Thu, 31 Mar 2022 16:51:52 +0300 Subject: fix gsm_bts_get_cbch(): CBCH can be allocated on Cn According to 3GPP TS 45.002, table 3, unlike the CCCH+SDCCH/4+CBCH combination, which can only be allocated on C0/TS0, the SDCCH/8+CBCH can be allocated on C0..n/TS0..3. In other words, having CBCH on e.g. TRX1/C1 is perfectly legal. This is why in gsm_bts_get_cbch() we should check all transceivers, not just the C0. Change-Id: Ie79ccff4f8f0f1134757ec0c35e18b58081cc158 Related: SYS#5905 --- src/osmo-bsc/bts.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/src/osmo-bsc/bts.c b/src/osmo-bsc/bts.c index d09aa4827..843d7111b 100644 --- a/src/osmo-bsc/bts.c +++ b/src/osmo-bsc/bts.c @@ -562,22 +562,23 @@ void gsm_bts_cell_id_list(struct gsm0808_cell_id_list2 *cell_id_list, const stru /* return the gsm_lchan for the CBCH (if it exists at all) */ struct gsm_lchan *gsm_bts_get_cbch(struct gsm_bts *bts) { - struct gsm_lchan *lchan = NULL; struct gsm_bts_trx *trx = bts->c0; + /* According to 3GPP TS 45.002, table 3, CBCH can be allocated + * either on C0/TS0 (CCCH+SDCCH4) or on C0..n/TS0..3 (SDCCH/8). */ if (trx->ts[0].pchan_from_config == GSM_PCHAN_CCCH_SDCCH4_CBCH) - lchan = &trx->ts[0].lchan[2]; - else { - int i; - for (i = 0; i < 8; i++) { - if (trx->ts[i].pchan_from_config == GSM_PCHAN_SDCCH8_SACCH8C_CBCH) { - lchan = &trx->ts[i].lchan[2]; - break; - } + return &trx->ts[0].lchan[2]; /* C0/TS0 */ + + llist_for_each_entry(trx, &bts->trx_list, list) { /* C0..n */ + unsigned int tn; + for (tn = 0; tn < 4; tn++) { /* TS0..3 */ + struct gsm_bts_trx_ts *ts = &trx->ts[tn]; + if (ts->pchan_from_config == GSM_PCHAN_SDCCH8_SACCH8C_CBCH) + return &ts->lchan[2]; } } - return lchan; + return NULL; } int gsm_set_bts_type(struct gsm_bts *bts, enum gsm_bts_type type) -- cgit v1.2.3