From a32431972dc9ca38ad1cc192082cdc49c7eb2809 Mon Sep 17 00:00:00 2001 From: Neels Hofmeyr Date: Sat, 5 Jun 2021 23:52:49 +0200 Subject: hodec2: implement upgrade TCH/H -> TCH/F (without AFS bias) Pass flag into find_alternative_lchan() indicating that a TCH/H channel has low ratings (rxqual or rxlev, doesn't matter). Heed this flag in the last round, the requirement A check, and allow candidates that have equal rxlev, if they result in an upgrade from TCH/H to TCH/F. This allows intra-cell upgrades to TCH/F. An important point is that this patch allows upgrade to TCH/F *without* the AFS bias setting. See also I315f24123ae016887ab91666870ce252e096f90f. Related: SYS#5198 SYS#5365 Change-Id: Id40d1cf8b58410c7d4eb87407fe8b8106e352438 --- src/osmo-bsc/handover_decision_2.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) (limited to 'src/osmo-bsc/handover_decision_2.c') diff --git a/src/osmo-bsc/handover_decision_2.c b/src/osmo-bsc/handover_decision_2.c index a866293a0..9d4f1e996 100644 --- a/src/osmo-bsc/handover_decision_2.c +++ b/src/osmo-bsc/handover_decision_2.c @@ -1251,7 +1251,7 @@ static void collect_candidates_for_lchan(struct gsm_lchan *lchan, * If minimum RXLEV, minimum RXQUAL or maximum TA are exceeded, the caller should pass * include_weaker_rxlev=true so that handover is performed despite congestion. */ -static int find_alternative_lchan(struct gsm_lchan *lchan, bool include_weaker_rxlev) +static int find_alternative_lchan(struct gsm_lchan *lchan, bool include_weaker_rxlev, bool request_upgrade_to_tch_f) { struct gsm_bts *bts = lchan->ts->trx->bts; int ahs = (gsm48_chan_mode_to_non_vamos(lchan->current_ch_mode_rate.chan_mode) == GSM48_CMODE_SPEECH_AMR @@ -1372,7 +1372,11 @@ static int find_alternative_lchan(struct gsm_lchan *lchan, bool include_weaker_r && clist[i].target.bts) afs_bias = ho_get_hodec2_afs_bias_rxlev(clist[i].target.bts->ho); better += afs_bias; - if (better > best_better_db) { + if (better > best_better_db + || (better >= best_better_db /* Upgrade from TCH/H to TCH/F: allow for equal rxlev */ + && request_upgrade_to_tch_f + && is_upgrade_to_tchf(&clist[i], REQUIREMENT_A_MASK))) { + best_cand = &clist[i]; best_better_db = better; best_applied_afs_bias = afs_bias? true : false; @@ -1494,7 +1498,7 @@ static void on_measurement_report(struct gsm_meas_rep *mr) global_ho_reason = HO_REASON_BAD_QUALITY; LOGPHOLCHAN(lchan, LOGL_INFO, "Trying handover/assignment due to bad quality\n"); } - find_alternative_lchan(lchan, true); + find_alternative_lchan(lchan, true, true); return; } @@ -1503,7 +1507,7 @@ static void on_measurement_report(struct gsm_meas_rep *mr) global_ho_reason = HO_REASON_LOW_RXLEVEL; LOGPHOLCHAN(lchan, LOGL_NOTICE, "RX level is TOO LOW: %d < %d\n", rxlev2dbm(av_rxlev), ho_get_hodec2_min_rxlev(bts->ho)); - find_alternative_lchan(lchan, true); + find_alternative_lchan(lchan, true, true); return; } @@ -1521,7 +1525,7 @@ static void on_measurement_report(struct gsm_meas_rep *mr) gsm_bts_cell_id(&bts_id, bts); penalty_timers_add(lchan->conn, &lchan->conn->hodec2.penalty_timers, &bts_id, ho_get_hodec2_penalty_max_dist(bts->ho)); - find_alternative_lchan(lchan, true); + find_alternative_lchan(lchan, true, false); return; } @@ -1532,7 +1536,7 @@ static void on_measurement_report(struct gsm_meas_rep *mr) /* try handover to a better cell */ if (av_rxlev >= 0 && (mr->nr % pwr_interval) == 0) { global_ho_reason = HO_REASON_BETTER_CELL; - find_alternative_lchan(lchan, false); + find_alternative_lchan(lchan, false, false); } } -- cgit v1.2.3