laforge has submitted this change. ( https://gerrit.osmocom.org/c/osmo-bsc/+/42289?usp=email )
Change subject: nokia_site: Change the LAPD N200 counter for RSL ......................................................................
nokia_site: Change the LAPD N200 counter for RSL
This commit raises the LAPD RSL N200 (retransmission) counter for Nokia RSL links. The reason is that the readiness of the TRX is not signalled (OML) nor can be queried from the BTS in any way, and on larger macro setups the TRX reset takes ~15 seconds, thus the RSL bootstrap times out before the TRX becomes ready.
This issue presents itself with UltraSite types, does not affect InSite or MetroSite (the later two are "integrated TRX" units). More modern macro setups like the Flexi or Multiradio are likely affected.
Runtime tested with InSite and UltraSite (multi-TRX).
Change-Id: Ie4bb804ea636eba2182586db13a625c5933eff31 --- M src/osmo-bsc/bts_nokia_site.c 1 file changed, 4 insertions(+), 1 deletion(-)
Approvals: fixeria: Looks good to me, but someone else must approve laforge: Looks good to me, approved pespin: Looks good to me, but someone else must approve Jenkins Builder: Verified
diff --git a/src/osmo-bsc/bts_nokia_site.c b/src/osmo-bsc/bts_nokia_site.c index 3800d45..c5e31b7 100644 --- a/src/osmo-bsc/bts_nokia_site.c +++ b/src/osmo-bsc/bts_nokia_site.c @@ -117,10 +117,13 @@ #endif
if (start) { + /* Raise N200 for RSL to fix slow TRX reset */ + if (link->sapi == SAPI_RSL) + ts->lapd->profile.n200 = 20; ts->lapd->profile.t200_sec = 1; ts->lapd->profile.t200_usec = 0; lapd_sap_start(ts->lapd, link->tei, - link->sapi); + link->sapi); } else lapd_sap_stop(ts->lapd, link->tei, link->sapi);