diff options
| author | Harald Welte <laforge@gnumonks.org> | 2014-12-28 15:00:45 +0100 |
|---|---|---|
| committer | Harald Welte <laforge@gnumonks.org> | 2014-12-30 00:35:28 +0100 |
| commit | 30f1f376383df3ae8d85e96542bf14d174c25d89 (patch) | |
| tree | d2c7cf085cce2a44ad055b741b25ef8794f105a2 /openbsc/src/libbsc/system_information.c | |
| parent | 65be6de155407142ddab44faf8aee5f8d5ebf628 (diff) | |
Add basic support for CBCH / SMS-CB (Cell Brroadcast)
We can now configure the pyisical channel types for CBCH either in the
CCCH+SDCCH4 or in the SDCCH8 chanel combination.
Depending on whether a CBCH exists on the BTS, we also generate the SI4
with matching CBCH channel description to notify the phones of the
existance of the CBCH.
There is now a VTY command how a SMS-CB message can be sent to a given
BTS.
We do not yet have any logic at all for actual scheduling of multiple
CBCH RSL messages towards one or multiple BTSs yet, though.
Diffstat (limited to 'openbsc/src/libbsc/system_information.c')
| -rw-r--r-- | openbsc/src/libbsc/system_information.c | 37 |
1 files changed, 35 insertions, 2 deletions
diff --git a/openbsc/src/libbsc/system_information.c b/openbsc/src/libbsc/system_information.c index 97827f2d9..29b9b191d 100644 --- a/openbsc/src/libbsc/system_information.c +++ b/openbsc/src/libbsc/system_information.c @@ -555,11 +555,34 @@ static int generate_si3(uint8_t *output, struct gsm_bts *bts) return sizeof(*si3) + rc; } +/* return the gsm_lchan for the CBCH (if it exists at all) */ +static struct gsm_lchan *bts_get_cbch(struct gsm_bts *bts) +{ + struct gsm_lchan *lchan = NULL; + struct gsm_bts_trx *trx = bts->c0; + + if (trx->ts[0].pchan == 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 == GSM_PCHAN_SDCCH8_SACCH8C_CBCH) { + lchan = &trx->ts[i].lchan[2]; + break; + } + } + } + + return lchan; +} + static int generate_si4(uint8_t *output, struct gsm_bts *bts) { int rc; struct gsm48_system_information_type_4 *si4 = (struct gsm48_system_information_type_4 *) output; + struct gsm_lchan *cbch_lchan; + uint8_t *restoct = si4->data; /* length of all IEs present except SI4 rest octets and l2_plen */ int l2_plen = sizeof(*si4) - 1; @@ -577,15 +600,25 @@ static int generate_si4(uint8_t *output, struct gsm_bts *bts) si4->rach_control = bts->si_common.rach_control; /* Optional: CBCH Channel Description + CBCH Mobile Allocation */ + cbch_lchan = bts_get_cbch(bts); + if (cbch_lchan) { + struct gsm48_chan_desc cd; + gsm48_lchan2chan_desc(&cd, cbch_lchan); + tv_fixed_put(si4->data, GSM48_IE_CBCH_CHAN_DESC, 4, + (uint8_t *) &cd); + l2_plen += 4 + 1; + restoct += 4 + 1; + /* we don't use hopping and thus don't need a CBCH MA */ + } si4->header.l2_plen = (l2_plen << 2) | 1; /* SI4 Rest Octets (10.5.2.35), containing Optional Power offset, GPRS Indicator, Cell Identity, LSA ID, Selection Parameter */ - rc = rest_octets_si4(si4->data, &si_info); + rc = rest_octets_si4(restoct, &si_info); - return sizeof(*si4) + rc; + return l2_plen + 1 + rc; } static int generate_si5(uint8_t *output, struct gsm_bts *bts) |