/* * (C) 2013 by Andreas Eversberg * (C) 2015-2017 by Harald Welte * Contributions by sysmocom - s.f.m.c. GmbH * * All Rights Reserved * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with this program. If not, see . * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* 3GPP TS 45.009, table 3.2.1.3-{2,4}: AMR on Uplink TCH/H. * * +---+---+---+---+---+---+ * | a | b | c | d | e | f | Burst 'a' received first * +---+---+---+---+---+---+ * ^^^^^^^^^^^^^^^^^^^^^^^ FACCH frame (bursts 'a' .. 'f') * ^^^^^^^^^^^^^^^ Speech frame (bursts 'a' .. 'd') * * TDMA frame number of burst 'f' is always used as the table index. */ static const uint8_t sched_tchh_ul_amr_cmi_map[26] = { [10] = 1, /* TCH/H(0): a=0 / d=6 / f=10 */ [19] = 1, /* TCH/H(0): a=8 / d=15 / f=19 */ [2] = 1, /* TCH/H(0): a=17 / d=23 / f=2 */ [11] = 1, /* TCH/H(1): a=1 / d=7 / f=11 */ [20] = 1, /* TCH/H(1): a=9 / d=16 / f=20 */ [3] = 1, /* TCH/H(1): a=18 / d=24 / f=3 */ }; /* 3GPP TS 45.002, table 1 in clause 7: Mapping tables. * TDMA frame number of burst 'f' is always used as the table index. */ static const uint8_t sched_tchh_ul_facch_map[26] = { [10] = 1, /* FACCH/H(0): B0(0,2,4,6,8,10) */ [11] = 1, /* FACCH/H(1): B0(1,3,5,7,9,11) */ [19] = 1, /* FACCH/H(0): B1(8,10,13,15,17,19) */ [20] = 1, /* FACCH/H(1): B1(9,11,14,16,18,20) */ [2] = 1, /* FACCH/H(0): B2(17,19,21,23,0,2) */ [3] = 1, /* FACCH/H(1): B2(18,20,22,24,1,3) */ }; /*! \brief a single TCH/H burst was received by the PHY, process it */ int rx_tchh_fn(struct l1sched_ts *l1ts, const struct trx_ul_burst_ind *bi) { struct l1sched_chan_state *chan_state = &l1ts->chan_state[bi->chan]; struct gsm_lchan *lchan = chan_state->lchan; sbit_t *burst, **bursts_p = &chan_state->ul_bursts; uint8_t *mask = &chan_state->ul_mask; uint8_t rsl_cmode = chan_state->rsl_cmode; uint8_t tch_mode = chan_state->tch_mode; uint8_t tch_data[128]; /* just to be safe */ int rc = 0; /* initialize to make gcc happy */ int amr = 0; int n_errors = 0; int n_bits_total = 0; bool bfi_flag = false; enum sched_meas_avg_mode meas_avg_mode = SCHED_MEAS_AVG_M_S6N4; struct l1sched_meas_set meas_avg; unsigned int fn_begin; uint16_t ber10k = 0; uint8_t is_sub = 0; uint8_t ft; bool fn_is_cmi; /* If handover RACH detection is turned on, treat this burst as an Access Burst. * Handle NOPE.ind as usually to ensure proper Uplink measurement reporting. */ if (chan_state->ho_rach_detect == 1 && ~bi->flags & TRX_BI_F_NOPE_IND) return rx_rach_fn(l1ts, bi); LOGL1SB(DL1P, LOGL_DEBUG, l1ts, bi, "Received TCH/H, bid=%u\n", bi->bid); /* allocate burst memory, if not already */ if (!*bursts_p) { *bursts_p = talloc_zero_size(l1ts, 696); if (!*bursts_p) return -ENOMEM; } /* shift the buffer by 2 bursts leftwards */ if (bi->bid == 0) { memcpy(*bursts_p, *bursts_p + 232, 232); memcpy(*bursts_p + 232, *bursts_p + 464, 232); memset(*bursts_p + 464, 0, 232); *mask = *mask << 2; } /* update mask */ *mask |= (1 << bi->bid); /* store measurements */ trx_sched_meas_push(chan_state, bi); /* copy burst to end of buffer of 6 bursts */ burst = *bursts_p + bi->bid * 116 + 464; if (bi->burst_len > 0) { memcpy(burst, bi->burst + 3, 58); memcpy(burst + 58, bi->burst + 87, 58); } else memset(burst, 0, 116); /* wait until complete set of bursts */ if (bi->bid != 1) return 0; /* fill up the burst buffer so that we have 6 bursts in there */ if (OSMO_UNLIKELY((*mask & 0x3f) != 0x3f)) { LOGL1SB(DL1P, LOGL_DEBUG, l1ts, bi, "UL burst buffer is not filled up: mask=0x%02x != 0x3f\n", *mask); return 0; /* TODO: send BFI */ } /* skip decoding of the last 4 bursts of FACCH/H */ if (chan_state->ul_ongoing_facch) { chan_state->ul_ongoing_facch = 0; /* we have already sent the first BFI when a FACCH/H frame * was decoded (see below), now send the second one. */ trx_sched_meas_avg(chan_state, &meas_avg, meas_avg_mode); /* meas_avg.fn now contains TDMA frame number of the first burst */ fn_begin = meas_avg.fn; goto bfi; } /* decode * also shift buffer by 4 bursts for interleaving */ switch (tch_mode) { case GSM48_CMODE_SIGN: meas_avg_mode = SCHED_MEAS_AVG_M_S6N6; /* fall-through */ case GSM48_CMODE_SPEECH_V1: /* HR or signalling */ rc = gsm0503_tch_hr_decode(tch_data, *bursts_p, !sched_tchh_ul_facch_map[bi->fn % 26], &n_errors, &n_bits_total); if (rc == (GSM_HR_BYTES + 1)) { /* only for valid *speech* frames */ /* gsm0503_tch_hr_decode() prepends a ToC octet (see RFC5993), skip it */ bool is_sid = osmo_hr_check_sid(&tch_data[1], GSM_HR_BYTES); if (is_sid) /* Mark SID frames as such: F = 0, FT = 010 */ tch_data[0] = (0x02 << 4); lchan_set_marker(is_sid, lchan); /* DTXu */ } break; case GSM48_CMODE_SPEECH_AMR: /* AMR */ /* the first FN 0,8,17 or 1,9,18 defines that CMI is included * in frame, the first FN 4,13,21 or 5,14,22 defines that CMR * is included in frame. */ /* See comment in function rx_tchf_fn() */ switch (chan_state->amr_last_dtx) { case AHS_ONSET: case AHS_SID_FIRST_INH: case AHS_SID_UPDATE_INH: lchan_set_marker(false, lchan); break; } fn_is_cmi = sched_tchh_ul_amr_cmi_map[bi->fn % 26]; /* See comment in function rx_tchf_fn() */ amr = 2; rc = gsm0503_tch_ahs_decode_dtx(tch_data + amr, *bursts_p, !sched_tchh_ul_facch_map[bi->fn % 26], !fn_is_cmi, chan_state->codec, chan_state->codecs, &chan_state->ul_ft, &chan_state->ul_cmr, &n_errors, &n_bits_total, &chan_state->amr_last_dtx); /* Tag all frames that are not regular AMR voice frames as SUB-Frames */ if (chan_state->amr_last_dtx != AMR_OTHER) { LOGL1SB(DL1P, LOGL_DEBUG, l1ts, bi, "Received AMR SID frame: %s\n", gsm0503_amr_dtx_frame_name(chan_state->amr_last_dtx)); is_sub = 1; } /* See comment in function rx_tchf_fn() */ switch (chan_state->amr_last_dtx) { case AHS_SID_FIRST_P1: case AHS_SID_FIRST_P2: case AHS_SID_UPDATE: case AHS_SID_UPDATE_CN: lchan_set_marker(true, lchan); lchan->rtp_tx_marker = false; break; } switch (chan_state->amr_last_dtx) { case AHS_SID_FIRST_P1: case AHS_SID_FIRST_P2: case AHS_SID_UPDATE: case AHS_SID_UPDATE_CN: case AHS_SID_FIRST_INH: case AHS_SID_UPDATE_INH: meas_avg_mode = SCHED_MEAS_AVG_M_S6N2; break; case AHS_ONSET: meas_avg_mode = SCHED_MEAS_AVG_M_S4N2; break; } /* only good speech frames get rtp header */ if (rc != GSM_MACBLOCK_LEN && rc >= 4) { if (chan_state->amr_last_dtx == AMR_OTHER) { ft = chan_state->codec[chan_state->ul_ft]; } else { /* SID frames will always get Frame Type Index 8 (AMR_SID) */ ft = AMR_SID; } rc = osmo_amr_rtp_enc(tch_data, chan_state->codec[chan_state->ul_cmr], ft, AMR_GOOD); } break; default: LOGL1SB(DL1P, LOGL_ERROR, l1ts, bi, "TCH mode %u invalid, please fix!\n", tch_mode); return -EINVAL; } ber10k = compute_ber10k(n_bits_total, n_errors); /* average measurements of the last N (depends on mode) bursts */ trx_sched_meas_avg(chan_state, &meas_avg, meas_avg_mode); /* meas_avg.fn now contains TDMA frame number of the first burst */ fn_begin = meas_avg.fn; if (tch_mode == GSM48_CMODE_SPEECH_AMR) trx_loop_amr_input(chan_state, &meas_avg); /* Check if the frame is bad */ if (rc < 0) { LOGL1SB(DL1P, LOGL_NOTICE, l1ts, bi, "Received bad data (%u/%u)\n", bi->fn % l1ts->mf_period, l1ts->mf_period); bfi_flag = true; } else if (rc < 4) { LOGL1SB(DL1P, LOGL_NOTICE, l1ts, bi, "Received bad data (%u/%u) with invalid codec mode %d\n", bi->fn % l1ts->mf_period, l1ts->mf_period, rc); bfi_flag = true; } if (rc != GSM_MACBLOCK_LEN && lchan->ecu_state) osmo_ecu_frame_in(lchan->ecu_state, bfi_flag, tch_data, rc); if (bfi_flag) goto bfi; /* FACCH */ if (rc == GSM_MACBLOCK_LEN) { chan_state->ul_ongoing_facch = 1; /* In order to provide an even stream of measurement reports in *speech* * mode, here we intentionally invalidate RSSI for FACCH, so that this * report gets dropped in process_l1sap_meas_data(). The averaged results * will be sent with the first (see below) and second (see above) BFIs. */ _sched_compose_ph_data_ind(l1ts, fn_begin, bi->chan, tch_data + amr, GSM_MACBLOCK_LEN, tch_mode == GSM48_CMODE_SIGN ? meas_avg.rssi : 0, meas_avg.toa256, meas_avg.ci_cb, ber10k, PRES_INFO_UNKNOWN); ber10k = 0; bfi: /* A FACCH/H frame replaces two speech frames, so we need to send two BFIs. * One is sent here, another will be sent two bursts later (see above). */ if (rsl_cmode == RSL_CMOD_SPD_SPEECH) { /* indicate bad frame */ if (lchan->tch.dtx.ul_sid) { /* DTXu: pause in progress. Push empty payload to upper layers */ rc = 0; goto compose_l1sap; } /* If there is an ECU active on this channel, use its output */ if (lchan->ecu_state) { rc = osmo_ecu_frame_out(lchan->ecu_state, tch_data); if (rc >= 0) /* Otherwise we send a BFI */ goto compose_l1sap; } switch (tch_mode) { case GSM48_CMODE_SPEECH_V1: /* HR */ tch_data[0] = 0x70; /* F = 0, FT = 111 */ memset(tch_data + 1, 0, 14); rc = 15; break; case GSM48_CMODE_SPEECH_AMR: /* AMR */ rc = osmo_amr_rtp_enc(tch_data, chan_state->codec[chan_state->ul_cmr], chan_state->codec[chan_state->ul_ft], AMR_BAD); if (rc < 2) { LOGL1SB(DL1P, LOGL_ERROR, l1ts, bi, "Failed to encode AMR_BAD frame (rc=%d), " "not sending BFI\n", rc); return -EINVAL; } memset(tch_data + 2, 0, rc - 2); break; default: LOGL1SB(DL1P, LOGL_ERROR, l1ts, bi, "TCH mode %u invalid, please fix!\n", tch_mode); return -EINVAL; } } } if (rsl_cmode != RSL_CMOD_SPD_SPEECH) return 0; compose_l1sap: /* TCH or BFI */ return _sched_compose_tch_ind(l1ts, fn_begin, bi->chan, tch_data, rc, meas_avg.toa256, ber10k, meas_avg.rssi, meas_avg.ci_cb, is_sub); } /* common section for generation of TCH bursts (TCH/H and TCH/F). * FIXME: this function is over-complicated, refactor / get rid of it. */ extern void tx_tch_common(struct l1sched_ts *l1ts, const struct trx_dl_burst_req *br, struct msgb **_msg_tch, struct msgb **_msg_facch); /* obtain a to-be-transmitted TCH/H (Half Traffic Channel) burst */ int tx_tchh_fn(struct l1sched_ts *l1ts, struct trx_dl_burst_req *br) { struct msgb *msg_tch = NULL, *msg_facch = NULL; struct l1sched_chan_state *chan_state = &l1ts->chan_state[br->chan]; uint8_t tch_mode = chan_state->tch_mode; ubit_t *burst, **bursts_p = &chan_state->dl_bursts; /* send burst, if we already got a frame */ if (br->bid > 0) { if (!*bursts_p) return -ENODEV; goto send_burst; } /* get TCH and/or FACCH */ tx_tch_common(l1ts, br, &msg_tch, &msg_facch); /* BURST BYPASS */ /* allocate burst memory, if not already, * otherwise shift buffer by 2 bursts for interleaving */ if (!*bursts_p) { *bursts_p = talloc_zero_size(l1ts, 696); if (!*bursts_p) return -ENOMEM; } else { memcpy(*bursts_p, *bursts_p + 232, 232); if (chan_state->dl_ongoing_facch) { memcpy(*bursts_p + 232, *bursts_p + 464, 232); memset(*bursts_p + 464, 0, 232); } else { memset(*bursts_p + 232, 0, 232); } } /* no message at all, send a dummy L2 frame on FACCH */ if (!msg_tch && !msg_facch && !chan_state->dl_ongoing_facch) { static const uint8_t dummy[GSM_MACBLOCK_LEN] = { 0x03, 0x03, 0x01, /* TODO: use randomized padding */ 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, 0x2b, }; LOGL1SB(DL1P, LOGL_INFO, l1ts, br, "No TCH or FACCH prim for transmit.\n"); gsm0503_tch_hr_encode(*bursts_p, dummy, sizeof(dummy)); goto send_burst; } /* encode bursts (prioritize FACCH) */ if (msg_facch) { gsm0503_tch_hr_encode(*bursts_p, msg_facch->l2h, msgb_l2len(msg_facch)); chan_state->dl_ongoing_facch = 1; /* first of two TCH frames */ chan_state->dl_facch_bursts = 6; } else if (chan_state->dl_ongoing_facch) /* second of two TCH frames */ chan_state->dl_ongoing_facch = 0; /* we are done with FACCH */ else if (tch_mode == GSM48_CMODE_SPEECH_AMR) /* the first FN 4,13,21 or 5,14,22 defines that CMI is included * in frame, the first FN 0,8,17 or 1,9,18 defines that CMR is * included in frame. */ gsm0503_tch_ahs_encode(*bursts_p, msg_tch->l2h + 2, msgb_l2len(msg_tch) - 2, !dl_amr_fn_is_cmi(br->fn), chan_state->codec, chan_state->codecs, chan_state->dl_ft, chan_state->dl_cmr); else gsm0503_tch_hr_encode(*bursts_p, msg_tch->l2h, msgb_l2len(msg_tch)); /* free message */ if (msg_tch) msgb_free(msg_tch); if (msg_facch) msgb_free(msg_facch); send_burst: /* compose burst */ burst = *bursts_p + br->bid * 116; memcpy(br->burst + 3, burst, 58); memcpy(br->burst + 61, TRX_GMSK_NB_TSC(br), 26); memcpy(br->burst + 87, burst + 58, 58); br->burst_len = GSM_BURST_LEN; if (chan_state->dl_facch_bursts > 0) { chan_state->dl_facch_bursts--; br->flags |= TRX_BR_F_FACCH; } LOGL1SB(DL1P, LOGL_DEBUG, l1ts, br, "Transmitting burst=%u.\n", br->bid); return 0; }