/* * Copyright (C) 2013 by Holger Hans Peter Freyther * * 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 extern "C" { #include #include #include #include #include #include #include #include #include #include #include #include } #include #include #define RFN_MODULUS 42432 #define RFN_THRESHOLD RFN_MODULUS / 2 extern void *tall_pcu_ctx; extern "C" { /* e must make sure to initialize logging before the BTS static * constructors are executed below, as those call libosmocore APIs that * require logging already to be initialized. */ __attribute__((constructor (101))) static void early_init(void) { if (!tall_pcu_ctx) { tall_pcu_ctx = talloc_named_const(NULL, 1, "Osmo-PCU context"); osmo_init_logging2(tall_pcu_ctx, &gprs_log_info); } } } static BTS s_bts; static struct osmo_tdef T_defs_bts[] = { { .T=3142, .default_val=20, .unit=OSMO_TDEF_S, .desc="timer (s)", .val=0 }, { .T=3169, .default_val=5, .unit=OSMO_TDEF_S, .desc="Reuse of USF and TFI(s) after the MS uplink TBF assignment is invalid (s)", .val=0 }, { .T=3191, .default_val=5, .unit=OSMO_TDEF_S, .desc="Reuse of TFI(s) after sending (1) last RLC Data Block on TBF(s), or (2) PACKET TBF RELEASE for an MBMS radio bearer (s)", .val=0 }, { .T=3193, .default_val=100, .unit=OSMO_TDEF_MS, .desc="Reuse of TFI(s) after reception of final PACKET DOWNLINK ACK/NACK from MS for TBF (ms)", .val=0 }, { .T=3195, .default_val=5, .unit=OSMO_TDEF_S, .desc="Reuse of TFI(s) upon no response from the MS (radio failure or cell change) for TBF/MBMS radio bearer (s)", .val=0 }, { .T=0, .default_val=0, .unit=OSMO_TDEF_S, .desc=NULL, .val=0 } /* empty item at the end */ }; static struct osmo_tdef T_defs_pcu[] = { { .T=1, .default_val=30, .unit=OSMO_TDEF_S, .desc="BSSGP (un)blocking procedures timer (s)", .val=0 }, { .T=2, .default_val=30, .unit=OSMO_TDEF_S, .desc="BSSGP reset procedure timer (s)", .val=0 }, { .T=3190, .default_val=5, .unit=OSMO_TDEF_S, .desc="Return to packet idle mode after Packet DL Assignment on CCCH (s)", .val=0}, { .T=-2000, .default_val=2, .unit=OSMO_TDEF_MS, .desc="Tbf reject for PRR timer (ms)", .val=0 }, { .T=-2001, .default_val=2, .unit=OSMO_TDEF_S, .desc="PACCH assignment timer (s)", .val=0 }, { .T=-2002, .default_val=200, .unit=OSMO_TDEF_MS, .desc="Waiting after IMM.ASS confirm timer (ms)", .val=0 }, { .T=-2030, .default_val=60, .unit=OSMO_TDEF_S, .desc="Time to keep an idle MS object alive (s)", .val=0 }, /* slightly above T3314 (default 44s, 24.008, 11.2.2) */ { .T=-2031, .default_val=2000, .unit=OSMO_TDEF_MS, .desc="Time to keep an idle DL TBF alive (ms)", .val=0 }, { .T=0, .default_val=0, .unit=OSMO_TDEF_S, .desc=NULL, .val=0 } /* empty item at the end */ }; /** * For gcc-4.4 compat do not use extended initializer list but keep the * order from the enum here. Once we support GCC4.7 and up we can change * the code below. */ static const struct rate_ctr_desc bts_ctr_description[] = { { "tbf:dl:alloc", "TBF DL Allocated "}, { "tbf:dl:freed", "TBF DL Freed "}, { "tbf:dl:aborted", "TBF DL Aborted "}, { "tbf:ul:alloc", "TBF UL Allocated "}, { "tbf:ul:freed", "TBF UL Freed "}, { "tbf:ul:aborted", "TBF UL Aborted "}, { "tbf:reused", "TBF Reused "}, { "tbf:alloc:algo-a", "TBF Alloc Algo A "}, { "tbf:alloc:algo-b", "TBF Alloc Algo B "}, { "tbf:failed:egprs-only", "TBF Failed EGPRS-only"}, { "rlc:sent", "RLC Sent "}, { "rlc:resent", "RLC Resent "}, { "rlc:restarted", "RLC Restarted "}, { "rlc:stalled", "RLC Stalled "}, { "rlc:nacked", "RLC Nacked "}, { "rlc:final_block_resent", "RLC Final Blk resent "}, { "rlc:ass:timedout", "RLC Assign Timeout "}, { "rlc:ass:failed", "RLC Assign Failed "}, { "rlc:ack:timedout", "RLC Ack Timeout "}, { "rlc:ack:failed", "RLC Ack Failed "}, { "rlc:rel:timedout", "RLC Release Timeout "}, { "rlc:late-block", "RLC Late Block "}, { "rlc:sent-dummy", "RLC Sent Dummy "}, { "rlc:sent-control", "RLC Sent Control "}, { "rlc:dl_bytes", "RLC DL Bytes "}, { "rlc:dl_payload_bytes", "RLC DL Payload Bytes "}, { "rlc:ul_bytes", "RLC UL Bytes "}, { "rlc:ul_payload_bytes", "RLC UL Payload Bytes "}, { "decode:errors", "Decode Errors "}, { "sba:allocated", "SBA Allocated "}, { "sba:freed", "SBA Freed "}, { "sba:timedout", "SBA Timeout "}, { "llc:timeout", "Timedout Frames "}, { "llc:dropped", "Dropped Frames "}, { "llc:scheduled", "Scheduled Frames "}, { "llc:dl_bytes", "RLC encapsulated PDUs"}, { "llc:ul_bytes", "full PDUs received "}, { "rach:requests", "RACH requests "}, { "11bit_rach:requests", "11BIT_RACH requests "}, { "spb:uplink_first_segment", "First seg of UL SPB "}, { "spb:uplink_second_segment", "Second seg of UL SPB "}, { "spb:downlink_first_segment", "First seg of DL SPB "}, { "spb:downlink_second_segment","Second seg of DL SPB "}, { "immediate:assignment_UL", "Immediate Assign UL "}, { "immediate:assignment_rej", "Immediate Assign Rej "}, { "immediate:assignment_DL", "Immediate Assign DL "}, { "channel:request_description","Channel Request Desc "}, { "pkt:ul_assignment", "Packet UL Assignment "}, { "pkt:access_reject", "Packet Access Reject "}, { "pkt:dl_assignment", "Packet DL Assignment "}, { "ul:control", "UL control Block "}, { "ul:assignment_poll_timeout", "UL Assign Timeout "}, { "ul:assignment_failed", "UL Assign Failed "}, { "dl:assignment_timeout", "DL Assign Timeout "}, { "dl:assignment_failed", "DL Assign Failed "}, { "pkt:ul_ack_nack_timeout", "PUAN Poll Timeout "}, { "pkt:ul_ack_nack_failed", "PUAN poll Failed "}, { "pkt:dl_ack_nack_timeout", "PDAN poll Timeout "}, { "pkt:dl_ack_nack_failed", "PDAN poll Failed "}, { "gprs:downlink_cs1", "CS1 downlink "}, { "gprs:downlink_cs2", "CS2 downlink "}, { "gprs:downlink_cs3", "CS3 downlink "}, { "gprs:downlink_cs4", "CS4 downlink "}, { "egprs:downlink_mcs1", "MCS1 downlink "}, { "egprs:downlink_mcs2", "MCS2 downlink "}, { "egprs:downlink_mcs3", "MCS3 downlink "}, { "egprs:downlink_mcs4", "MCS4 downlink "}, { "egprs:downlink_mcs5", "MCS5 downlink "}, { "egprs:downlink_mcs6", "MCS6 downlink "}, { "egprs:downlink_mcs7", "MCS7 downlink "}, { "egprs:downlink_mcs8", "MCS8 downlink "}, { "egprs:downlink_mcs9", "MCS9 downlink "}, { "gprs:uplink_cs1", "CS1 Uplink "}, { "gprs:uplink_cs2", "CS2 Uplink "}, { "gprs:uplink_cs3", "CS3 Uplink "}, { "gprs:uplink_cs4", "CS4 Uplink "}, { "egprs:uplink_mcs1", "MCS1 Uplink "}, { "egprs:uplink_mcs2", "MCS2 Uplink "}, { "egprs:uplink_mcs3", "MCS3 Uplink "}, { "egprs:uplink_mcs4", "MCS4 Uplink "}, { "egprs:uplink_mcs5", "MCS5 Uplink "}, { "egprs:uplink_mcs6", "MCS6 Uplink "}, { "egprs:uplink_mcs7", "MCS7 Uplink "}, { "egprs:uplink_mcs8", "MCS8 Uplink "}, { "egprs:uplink_mcs9", "MCS9 Uplink "}, }; static const struct rate_ctr_group_desc bts_ctrg_desc = { "bts", "BTS Statistics", OSMO_STATS_CLASS_GLOBAL, ARRAY_SIZE(bts_ctr_description), bts_ctr_description, }; static const struct osmo_stat_item_desc bts_stat_item_description[] = { { "ms.present", "MS Present ", OSMO_STAT_ITEM_NO_UNIT, 4, 0}, }; static const struct osmo_stat_item_group_desc bts_statg_desc = { "bts", "BTS Statistics", OSMO_STATS_CLASS_GLOBAL, ARRAY_SIZE(bts_stat_item_description), bts_stat_item_description, }; static void bts_init(struct gprs_rlcmac_bts *bts, BTS* bts_obj) { memset(bts, 0, sizeof(*bts)); bts->fc_interval = 1; bts->initial_cs_dl = bts->initial_cs_ul = 1; bts->initial_mcs_dl = bts->initial_mcs_ul = 1; bts->cs_mask = 1 << 0; /* CS-1 always enabled by default */ bts->n3101 = 10; bts->n3103 = 4; bts->n3105 = 8; bts->alpha = 0; /* a = 0.0 */ bts->si13_is_set = false; bts->cs_adj_enabled = 1; bts->cs_adj_upper_limit = 33; /* Decrease CS if the error rate is above */ bts->cs_adj_lower_limit = 10; /* Increase CS if the error rate is below */ bts->vty.max_cs_ul = MAX_GPRS_CS; bts->vty.max_cs_dl = MAX_GPRS_CS; bts->vty.max_mcs_ul = MAX_EDGE_MCS; bts->vty.max_mcs_dl = MAX_EDGE_MCS; /* CS-1 to CS-4 */ bts->cs_lqual_ranges[0].low = -256; bts->cs_lqual_ranges[0].high = 6; bts->cs_lqual_ranges[1].low = 5; bts->cs_lqual_ranges[1].high = 8; bts->cs_lqual_ranges[2].low = 7; bts->cs_lqual_ranges[2].high = 13; bts->cs_lqual_ranges[3].low = 12; bts->cs_lqual_ranges[3].high = 256; /* MCS-1 to MCS-9 */ /* Default thresholds are referenced from literature */ /* Fig. 2.3, Chapter 2, Optimizing Wireless Communication Systems, Springer (2009) */ bts->mcs_lqual_ranges[0].low = -256; bts->mcs_lqual_ranges[0].high = 6; bts->mcs_lqual_ranges[1].low = 5; bts->mcs_lqual_ranges[1].high = 8; bts->mcs_lqual_ranges[2].low = 7; bts->mcs_lqual_ranges[2].high = 13; bts->mcs_lqual_ranges[3].low = 12; bts->mcs_lqual_ranges[3].high = 15; bts->mcs_lqual_ranges[4].low = 14; bts->mcs_lqual_ranges[4].high = 17; bts->mcs_lqual_ranges[5].low = 16; bts->mcs_lqual_ranges[5].high = 18; bts->mcs_lqual_ranges[6].low = 17; bts->mcs_lqual_ranges[6].high = 20; bts->mcs_lqual_ranges[7].low = 19; bts->mcs_lqual_ranges[7].high = 24; bts->mcs_lqual_ranges[8].low = 23; bts->mcs_lqual_ranges[8].high = 256; bts->cs_downgrade_threshold = 200; /* TODO: increase them when CRBB decoding is implemented */ bts->ws_base = 64; bts->ws_pdch = 0; bts->llc_codel_interval_msec = LLC_CODEL_USE_DEFAULT; bts->llc_idle_ack_csec = 10; /* * By default resegmentation is supported in DL * can also be configured through VTY */ bts->dl_arq_type = EGPRS_ARQ1; bts->app_info = NULL; bts->bts = bts_obj; bts->dl_tbf_preemptive_retransmission = true; bts->T_defs_bts = T_defs_bts; bts->T_defs_pcu = T_defs_pcu; osmo_tdefs_reset(bts->T_defs_bts); osmo_tdefs_reset(bts->T_defs_pcu); /* initialize back pointers */ for (size_t trx_no = 0; trx_no < ARRAY_SIZE(bts->trx); ++trx_no) { struct gprs_rlcmac_trx *trx = &bts->trx[trx_no]; trx->trx_no = trx_no; trx->bts = bts_obj; for (size_t ts_no = 0; ts_no < ARRAY_SIZE(trx->pdch); ++ts_no) { struct gprs_rlcmac_pdch *pdch = &trx->pdch[ts_no]; pdch->init_ptcch_msg(); pdch->ts_no = ts_no; pdch->trx = trx; } } } BTS* BTS::main_bts() { return &s_bts; } struct gprs_rlcmac_bts *BTS::bts_data() { return &m_bts; } struct gprs_rlcmac_bts *bts_main_data() { return BTS::main_bts()->bts_data(); } void bts_cleanup() { return BTS::main_bts()->cleanup(); } struct rate_ctr_group *bts_main_data_stats() { return BTS::main_bts()->rate_counters(); } BTS::BTS() : m_cur_fn(0) , m_cur_blk_fn(-1) , m_max_cs_dl(MAX_GPRS_CS) , m_max_cs_ul(MAX_GPRS_CS) , m_max_mcs_dl(MAX_EDGE_MCS) , m_max_mcs_ul(MAX_EDGE_MCS) , m_pollController(*this) , m_sba(*this) , m_ms_store(this) { bts_init(&m_bts, this); /* The static allocator might have already registered the counter group. If this happens and we still called explicitly (in tests/ for example) than just allocate the group with different index. This shall be removed once weget rid of BTS singleton */ if (rate_ctr_get_group_by_name_idx(bts_ctrg_desc.group_name_prefix, 0)) m_ratectrs = rate_ctr_group_alloc(tall_pcu_ctx, &bts_ctrg_desc, 1); else m_ratectrs = rate_ctr_group_alloc(tall_pcu_ctx, &bts_ctrg_desc, 0); OSMO_ASSERT(m_ratectrs); m_statg = osmo_stat_item_group_alloc(tall_pcu_ctx, &bts_statg_desc, 0); OSMO_ASSERT(m_statg); } void BTS::cleanup() { /* this can cause counter updates and must not be left to the * m_ms_store's destructor */ m_ms_store.cleanup(); if (m_ratectrs) { rate_ctr_group_free(m_ratectrs); m_ratectrs = NULL; } if (m_statg) { osmo_stat_item_group_free(m_statg); m_statg = NULL; } if (m_bts.app_info) { msgb_free(m_bts.app_info); m_bts.app_info = NULL; } } BTS::~BTS() { cleanup(); } void BTS::set_current_frame_number(int fn) { /* The UL frame numbers lag 3 behind the DL frames and the data * indication is only sent after all 4 frames of the block have been * received. Sometimes there is an idle frame between the end of one * and start of another frame (every 3 blocks). So the timeout should * definitely be there if we're more than 8 frames past poll_fn. Let's * stay on the safe side and say 13 or more. An additional delay can * happen due to the block processing time in the DSP, so the delay of * decoded blocks relative to the timing clock can be much larger. * Values up to 50 frames have been observed under load. */ const static int max_delay = 60; m_cur_fn = fn; m_pollController.expireTimedout(m_cur_fn, max_delay); } static inline int delta_fn(int fn, int to) { return (fn + GSM_MAX_FN * 3 / 2 - to) % GSM_MAX_FN - GSM_MAX_FN/2; } void BTS::set_current_block_frame_number(int fn, unsigned max_delay) { int delay = 0; const int late_block_delay_thresh = 13; const int fn_update_ok_min_delay = -500; const int fn_update_ok_max_delay = 0; /* frame numbers in the received blocks are assumed to be strongly * monotonic. */ if (m_cur_blk_fn >= 0) { int delta = delta_fn(fn, m_cur_blk_fn); if (delta <= 0) return; } /* Check block delay vs. the current frame number */ if (current_frame_number() != 0) delay = delta_fn(fn, current_frame_number()); if (delay <= -late_block_delay_thresh) { LOGP(DRLCMAC, LOGL_NOTICE, "Late RLC block, FN delta: %d FN: %d curFN: %d\n", delay, fn, current_frame_number()); do_rate_ctr_inc(CTR_RLC_LATE_BLOCK); } m_cur_blk_fn = fn; if (delay < fn_update_ok_min_delay || delay > fn_update_ok_max_delay || current_frame_number() == 0) m_cur_fn = fn; m_pollController.expireTimedout(fn, max_delay); } int BTS::add_paging(uint8_t chan_needed, const struct osmo_mobile_identity *mi) { uint8_t l, trx, ts, any_tbf = 0; struct gprs_rlcmac_tbf *tbf; LListHead *pos; uint8_t slot_mask[8]; int8_t first_ts; /* must be signed */ LListHead *tbfs_lists[] = { &m_ul_tbfs, &m_dl_tbfs, NULL }; if (log_check_level(DRLCMAC, LOGL_INFO)) { char str[64]; osmo_mobile_identity_to_str_buf(str, sizeof(str), mi); LOGP(DRLCMAC, LOGL_INFO, "Add RR paging: chan-needed=%d MI=%s\n", chan_needed, str); } /* collect slots to page * Mark slots for every TBF, but only mark one of it. * Mark only the first slot found. * Don't mark, if TBF uses a different slot that is already marked. */ memset(slot_mask, 0, sizeof(slot_mask)); for (l = 0; tbfs_lists[l]; l++) { llist_for_each(pos, tbfs_lists[l]) { tbf = pos->entry(); first_ts = -1; for (ts = 0; ts < 8; ts++) { if (tbf->pdch[ts]) { /* remember the first slot found */ if (first_ts < 0) first_ts = ts; /* break, if we already marked a slot */ if ((slot_mask[tbf->trx->trx_no] & (1 << ts))) break; } } /* mark first slot found, if none is marked already */ if (ts == 8 && first_ts >= 0) { LOGPTBF(tbf, LOGL_DEBUG, "uses " "TRX=%d TS=%d, so we mark\n", tbf->trx->trx_no, first_ts); slot_mask[tbf->trx->trx_no] |= (1 << first_ts); } else LOGPTBF(tbf, LOGL_DEBUG, "uses " "already marked TRX=%d TS=%d\n", tbf->trx->trx_no, ts); } } /* Now we have a list of marked slots. Every TBF uses at least one * of these slots. */ /* schedule paging to all marked slots */ for (trx = 0; trx < 8; trx++) { if (slot_mask[trx] == 0) continue; for (ts = 0; ts < 8; ts++) { if ((slot_mask[trx] & (1 << ts))) { /* schedule */ if (!m_bts.trx[trx].pdch[ts].add_paging(chan_needed, mi)) return -ENOMEM; LOGP(DRLCMAC, LOGL_INFO, "Paging on PACCH of TRX=%d TS=%d\n", trx, ts); any_tbf = 1; } } } if (!any_tbf) LOGP(DRLCMAC, LOGL_INFO, "No paging, because no TBF\n"); return 0; } void BTS::send_gsmtap_rach(enum pcu_gsmtap_category categ, uint8_t channel, const struct rach_ind_params *rip) { struct pcu_l1_meas meas; uint8_t ra_buf[2]; /* 3GPP TS 44.004 defines 11 bit RA as follows: xxxx xxxx .... .yyy * On the PCUIF, we get 16 bit machne dependent number (LE/BE) * Over GSMTAP we send the following: xxxx xxxx yyy. .... * This simplifies parsing in Wireshark using its CSN.1 codec. */ if (rip->is_11bit) { ra_buf[0] = (uint8_t) ((rip->ra >> 3) & 0xff); ra_buf[1] = (uint8_t) ((rip->ra << 5) & 0xff); } else { ra_buf[0] = (uint8_t) (rip->ra & 0xff); } send_gsmtap_meas(categ, true, rip->trx_nr, rip->ts_nr, channel, rfn_to_fn(rip->rfn), ra_buf, rip->is_11bit ? 2 : 1, &meas); } void BTS::send_gsmtap(enum pcu_gsmtap_category categ, bool uplink, uint8_t trx_no, uint8_t ts_no, uint8_t channel, uint32_t fn, const uint8_t *data, unsigned int len) { struct pcu_l1_meas meas; send_gsmtap_meas(categ, uplink, trx_no, ts_no, channel, fn, data, len, &meas); } void BTS::send_gsmtap_meas(enum pcu_gsmtap_category categ, bool uplink, uint8_t trx_no, uint8_t ts_no, uint8_t channel, uint32_t fn, const uint8_t *data, unsigned int len, struct pcu_l1_meas *meas) { uint16_t arfcn; /* check if category is activated at all */ if (!(m_bts.gsmtap_categ_mask & (1 << categ))) return; arfcn = m_bts.trx[trx_no].arfcn; if (uplink) arfcn |= GSMTAP_ARFCN_F_UPLINK; /* GSMTAP needs the SNR here, but we only have C/I (meas->link_qual). Those are not the same, but there is no known way to convert them, let's pass C/I instead of nothing */ gsmtap_send(m_bts.gsmtap, arfcn, ts_no, channel, 0, fn, meas->rssi, meas->link_qual, data, len); } static inline bool tbf_check(gprs_rlcmac_tbf *tbf, uint32_t fn, uint8_t trx_no, uint8_t ts) { if (tbf->state_is_not(GPRS_RLCMAC_RELEASING) && tbf->poll_scheduled() && tbf->poll_fn == fn && tbf->trx->trx_no == trx_no && tbf->poll_ts == ts) return true; return false; } gprs_rlcmac_dl_tbf *BTS::dl_tbf_by_poll_fn(uint32_t fn, uint8_t trx, uint8_t ts) { LListHead *pos; /* only one TBF can poll on specific TS/FN, because scheduler can only * schedule one downlink control block (with polling) at a FN per TS */ llist_for_each(pos, &m_dl_tbfs) { if (tbf_check(pos->entry(), fn, trx, ts)) return as_dl_tbf(pos->entry()); } return NULL; } gprs_rlcmac_ul_tbf *BTS::ul_tbf_by_poll_fn(uint32_t fn, uint8_t trx, uint8_t ts) { LListHead *pos; /* only one TBF can poll on specific TS/FN, because scheduler can only * schedule one downlink control block (with polling) at a FN per TS */ llist_for_each(pos, &m_ul_tbfs) { if (tbf_check(pos->entry(), fn, trx, ts)) return as_ul_tbf(pos->entry()); } return NULL; } /* lookup downlink TBF Entity (by TFI) */ gprs_rlcmac_dl_tbf *BTS::dl_tbf_by_tfi(uint8_t tfi, uint8_t trx, uint8_t ts) { if (trx >= 8 || ts >= 8) return NULL; return m_bts.trx[trx].pdch[ts].dl_tbf_by_tfi(tfi); } /* lookup uplink TBF Entity (by TFI) */ gprs_rlcmac_ul_tbf *BTS::ul_tbf_by_tfi(uint8_t tfi, uint8_t trx, uint8_t ts) { if (trx >= 8 || ts >= 8) return NULL; return m_bts.trx[trx].pdch[ts].ul_tbf_by_tfi(tfi); } static unsigned int trx_count_free_tfi(const struct gprs_rlcmac_trx *trx, enum gprs_rlcmac_tbf_direction dir, uint8_t *first_free_tfi) { const struct gprs_rlcmac_pdch *pdch; uint8_t ts; unsigned int i; unsigned int free_tfi_cnt = 0; bool has_pdch = false; uint32_t mask = NO_FREE_TFI; for (ts = 0; ts < ARRAY_SIZE(trx->pdch); ts++) { pdch = &trx->pdch[ts]; if (!pdch->is_enabled()) continue; has_pdch = true; mask &= ~pdch->assigned_tfi(dir); } if (!has_pdch || !mask) { *first_free_tfi = (uint8_t)-1; return 0; } /* Count free tfis and return */ for (i = 0; i < sizeof(mask) * 8 ; i++) { if (mask & 1) { if (free_tfi_cnt == 0) *first_free_tfi = i; free_tfi_cnt++; } mask >>= 1; } return free_tfi_cnt; } /* * Search for free TFI and return TFI, TRX. This method returns the first TFI * that is currently not used in any PDCH of a the TRX with least TFIs currently * assigned. Negative values indicate errors. */ int BTS::tfi_find_free(enum gprs_rlcmac_tbf_direction dir, uint8_t *_trx, int8_t use_trx) const { uint8_t trx_from, trx_to, trx; uint8_t best_trx_nr = 0xff; unsigned int best_cnt = 0; uint8_t best_first_tfi = 0; if (use_trx >= 0 && use_trx < 8) trx_from = trx_to = use_trx; else { trx_from = 0; trx_to = 7; } /* find a TFI that is unused on all PDCH */ for (trx = trx_from; trx <= trx_to; trx++) { uint8_t tmp_first_tfi; unsigned int tmp_cnt; tmp_cnt = trx_count_free_tfi(&m_bts.trx[trx], dir, &tmp_first_tfi); if (tmp_cnt > best_cnt) { best_cnt = tmp_cnt; best_first_tfi = tmp_first_tfi; best_trx_nr = trx; } } if (best_trx_nr == 0xff || best_cnt == 0) { LOGP(DRLCMAC, LOGL_NOTICE, "No TFI available (suggested TRX: %d).\n", use_trx); return -EBUSY; } OSMO_ASSERT(best_first_tfi < 32); LOGP(DRLCMAC, LOGL_DEBUG, "Found first unallocated TRX=%d TFI=%d\n", best_trx_nr, best_first_tfi); *_trx = best_trx_nr; return best_first_tfi; } int BTS::rcv_imm_ass_cnf(const uint8_t *data, uint32_t fn) { struct gprs_rlcmac_dl_tbf *dl_tbf = NULL; uint8_t plen; uint32_t tlli; GprsMs *ms; /* move to IA Rest Octets */ plen = data[0] >> 2; data += 1 + plen; if ((*data & 0xf0) != 0xd0) { LOGP(DRLCMAC, LOGL_ERROR, "Got IMM.ASS confirm, but rest " "octets do not start with bit sequence 'HH01' " "(Packet Downlink Assignment)\n"); return -EINVAL; } /* get TLLI from downlink assignment */ tlli = (uint32_t)((*data++) & 0xf) << 28; tlli |= (*data++) << 20; tlli |= (*data++) << 12; tlli |= (*data++) << 4; tlli |= (*data++) >> 4; ms = ms_by_tlli(tlli); if (ms) dl_tbf = ms->dl_tbf(); if (!dl_tbf) { LOGP(DRLCMAC, LOGL_ERROR, "Got IMM.ASS confirm, but TLLI=%08x " "does not exit\n", tlli); return -EINVAL; } LOGP(DRLCMAC, LOGL_DEBUG, "Got IMM.ASS confirm for TLLI=%08x\n", tlli); if (dl_tbf->m_wait_confirm) T_START(dl_tbf, T0, -2002, "assignment (AGCH)", true); return 0; } /* Determine the full frame number from a relative frame number */ uint32_t BTS::rfn_to_fn(int32_t rfn) { int32_t m_cur_rfn; int32_t fn; int32_t fn_rounded; /* double-check that relative FN is not negative and fits into int32_t */ OSMO_ASSERT(rfn < GSM_MAX_FN); OSMO_ASSERT(rfn >= 0); /* Note: If a BTS is sending in a rach request it will be fully aware * of the frame number. If the PCU is used in a BSC-co-located setup. * The BSC will forward the incoming RACH request. The RACH request * only contains the relative frame number (Fn % 42432) in its request * reference. This PCU implementation has to fit both scenarios, so * we need to assume that Fn is a relative frame number. */ /* Ensure that all following calculations are performed with the * relative frame number */ if (rfn >= RFN_MODULUS) return rfn; /* Compute an internal relative frame number from the full internal frame number */ m_cur_rfn = m_cur_fn % RFN_MODULUS; /* Compute a "rounded" version of the internal frame number, which * exactly fits in the RFN_MODULUS raster */ fn_rounded = m_cur_fn - m_cur_rfn; /* If the delta between the internal and the external relative frame * number exceeds a certain limit, we need to assume that the incoming * rach request belongs to a the previous rfn period. To correct this, * we roll back the rounded frame number by one RFN_MODULUS */ if (abs(rfn - m_cur_rfn) > RFN_THRESHOLD) { LOGP(DRLCMAC, LOGL_DEBUG, "Race condition between rfn (%u) and m_cur_fn (%u) detected: rfn belongs to the previous modulus %u cycle, wrapping...\n", rfn, m_cur_fn, RFN_MODULUS); if (fn_rounded < RFN_MODULUS) { LOGP(DRLCMAC, LOGL_DEBUG, "Cornercase detected: wrapping crosses %u border\n", GSM_MAX_FN); fn_rounded = GSM_MAX_FN - (RFN_MODULUS - fn_rounded); } else fn_rounded -= RFN_MODULUS; } /* The real frame number is the sum of the rounded frame number and the * relative framenumber computed via RACH */ fn = fn_rounded + rfn; return fn; } /* 3GPP TS 44.060: * Table 11.2.5.2: PACKET CHANNEL REQUEST * Table 11.2.5a.2: EGPRS PACKET CHANNEL REQUEST * Both GPRS and EGPRS use same MultislotClass coding, but since PRACH is * deprecated, no PACKET CHANNEL REQUEST exists, which means for GPRS we will * receive CCCH RACH which doesn't contain any mslot class. Hence in the end we * can only receive EGPRS mslot class through 11-bit EGPRS PACKET CHANNEL REQUEST. */ static int parse_egprs_pkt_ch_req(uint16_t ra11, struct chan_req_params *chan_req) { EGPRS_PacketChannelRequest_t req; int rc; rc = decode_egprs_pkt_ch_req(ra11, &req); if (rc) { LOGP(DRLCMAC, LOGL_NOTICE, "Failed to decode " "EGPRS Packet Channel Request: rc=%d\n", rc); return rc; } LOGP(DRLCMAC, LOGL_INFO, "Rx EGPRS Packet Channel Request: %s\n", get_value_string(egprs_pkt_ch_req_type_names, req.Type)); switch (req.Type) { case EGPRS_PKT_CHAN_REQ_ONE_PHASE: chan_req->egprs_mslot_class = req.Content.MultislotClass + 1; chan_req->priority = req.Content.Priority + 1; break; case EGPRS_PKT_CHAN_REQ_SHORT: chan_req->priority = req.Content.Priority + 1; if (req.Content.NumberOfBlocks == 0) chan_req->single_block = true; break; case EGPRS_PKT_CHAN_REQ_ONE_PHASE_RED_LATENCY: chan_req->priority = req.Content.Priority + 1; break; /* Two phase access => single block is needed */ case EGPRS_PKT_CHAN_REQ_TWO_PHASE: case EGPRS_PKT_CHAN_REQ_TWO_PHASE_IPA: chan_req->priority = req.Content.Priority + 1; chan_req->single_block = true; break; /* Signalling => single block is needed */ case EGPRS_PKT_CHAN_REQ_SIGNALLING: case EGPRS_PKT_CHAN_REQ_SIGNALLING_IPA: chan_req->single_block = true; break; /* Neither unacknowledged RLC mode, nor emergency calls are supported */ case EGPRS_PKT_CHAN_REQ_ONE_PHASE_UNACK: case EGPRS_PKT_CHAN_REQ_EMERGENCY_CALL: case EGPRS_PKT_CHAN_REQ_DEDICATED_CHANNEL: LOGP(DRLCMAC, LOGL_NOTICE, "%s is not supported, rejecting\n", get_value_string(egprs_pkt_ch_req_type_names, req.Type)); return -ENOTSUP; default: LOGP(DRLCMAC, LOGL_ERROR, "Unknown EGPRS Packet Channel Request " "type=0x%02x, probably a bug in CSN.1 codec\n", req.Type); return -EINVAL; } return 0; } /* NOTE: chan_req needs to be zero-initialized by the caller */ static int parse_rach_ind(const struct rach_ind_params *rip, struct chan_req_params *chan_req) { int rc; switch (rip->burst_type) { case GSM_L1_BURST_TYPE_NONE: LOGP(DRLCMAC, LOGL_ERROR, "RACH.ind contains no burst type, assuming TS0\n"); /* fall-through */ case GSM_L1_BURST_TYPE_ACCESS_0: if (rip->is_11bit) { /* 11 bit Access Burst with TS0 => Packet Channel Request */ LOGP(DRLCMAC, LOGL_ERROR, "11 bit Packet Channel Request " "is not supported (PBCCH is deprecated)\n"); return -ENOTSUP; } /* 3GPP TS 44.018, table 9.1.8.1: 8 bit CHANNEL REQUEST. * Mask 01110xxx indicates single block packet access. */ chan_req->single_block = ((rip->ra & 0xf8) == 0x70); break; case GSM_L1_BURST_TYPE_ACCESS_1: case GSM_L1_BURST_TYPE_ACCESS_2: if (!rip->is_11bit) { /* TS1/TS2 => EGPRS Packet Channel Request (always 11 bit) */ LOGP(DRLCMAC, LOGL_ERROR, "11 bit Packet Channel Request " "is not supported (PBCCH is deprecated)\n"); return -ENOTSUP; } rc = parse_egprs_pkt_ch_req(rip->ra, chan_req); if (rc) return rc; break; default: LOGP(DRLCMAC, LOGL_ERROR, "RACH.ind contains unknown burst type 0x%02x " "(%u bit)\n", rip->burst_type, rip->is_11bit ? 11 : 8); return -EINVAL; } return 0; } int BTS::rcv_rach(const struct rach_ind_params *rip) { struct chan_req_params chan_req = { 0 }; struct gprs_rlcmac_ul_tbf *tbf = NULL; uint8_t trx_no, ts_no; uint32_t sb_fn = 0; uint8_t usf = 7; uint8_t tsc = 0; int plen, rc; do_rate_ctr_inc(CTR_RACH_REQUESTS); if (rip->is_11bit) do_rate_ctr_inc(CTR_11BIT_RACH_REQUESTS); /* Determine full frame number */ uint32_t Fn = rfn_to_fn(rip->rfn); uint8_t ta = qta2ta(rip->qta); send_gsmtap_rach(PCU_GSMTAP_C_UL_RACH, GSMTAP_CHANNEL_RACH, rip); LOGP(DRLCMAC, LOGL_DEBUG, "MS requests Uplink resource on CCCH/RACH: " "ra=0x%02x (%d bit) Fn=%u qta=%d\n", rip->ra, rip->is_11bit ? 11 : 8, Fn, rip->qta); /* Parse [EGPRS Packet] Channel Request from RACH.ind */ rc = parse_rach_ind(rip, &chan_req); if (rc) /* Send RR Immediate Assignment Reject */ goto send_imm_ass_rej; if (chan_req.single_block) LOGP(DRLCMAC, LOGL_DEBUG, "MS requests single block allocation\n"); else if (m_bts.force_two_phase) { LOGP(DRLCMAC, LOGL_DEBUG, "MS requests single block allocation, " "but we force two phase access\n"); chan_req.single_block = true; } /* TODO: handle Radio Priority (see 3GPP TS 44.060, table 11.2.5a.5) */ if (chan_req.priority > 0) LOGP(DRLCMAC, LOGL_NOTICE, "EGPRS Packet Channel Request indicates " "Radio Priority %u, however we ignore it\n", chan_req.priority); /* Should we allocate a single block or an Uplink TBF? */ if (chan_req.single_block) { rc = sba()->alloc(&trx_no, &ts_no, &sb_fn, ta); if (rc < 0) { LOGP(DRLCMAC, LOGL_NOTICE, "No PDCH resource for " "single block allocation: rc=%d\n", rc); /* Send RR Immediate Assignment Reject */ goto send_imm_ass_rej; } tsc = m_bts.trx[trx_no].pdch[ts_no].tsc; LOGP(DRLCMAC, LOGL_DEBUG, "Allocated a single block at " "SBFn=%u TRX=%u TS=%u\n", sb_fn, trx_no, ts_no); } else { GprsMs *ms = ms_alloc(0, chan_req.egprs_mslot_class); tbf = tbf_alloc_ul_tbf(&m_bts, ms, -1, true); if (!tbf) { LOGP(DRLCMAC, LOGL_NOTICE, "No PDCH resource for Uplink TBF\n"); /* Send RR Immediate Assignment Reject */ rc = -EBUSY; goto send_imm_ass_rej; } /* FIXME: Copy and paste with other routines.. */ tbf->set_ta(ta); TBF_SET_STATE(tbf, GPRS_RLCMAC_FLOW); TBF_ASS_TYPE_SET(tbf, GPRS_RLCMAC_FLAG_CCCH); T_START(tbf, T3169, 3169, "RACH (new UL-TBF)", true); trx_no = tbf->trx->trx_no; ts_no = tbf->first_ts; usf = tbf->m_usf[ts_no]; tsc = tbf->tsc(); } send_imm_ass_rej: /* Allocate a bit-vector for RR Immediate Assignment [Reject] */ struct bitvec *bv = bitvec_alloc(22, tall_pcu_ctx); /* without plen */ bitvec_unhex(bv, DUMMY_VEC); /* standard '2B'O padding */ if (rc != 0) { LOGP(DRLCMAC, LOGL_DEBUG, "Tx Immediate Assignment Reject on AGCH\n"); plen = Encoding::write_immediate_assignment_reject( bv, rip->ra, Fn, rip->burst_type); do_rate_ctr_inc(CTR_IMMEDIATE_ASSIGN_REJ); } else { LOGP(DRLCMAC, LOGL_DEBUG, "Tx Immediate Assignment on AGCH: " "TRX=%u (ARFCN %u) TS=%u TA=%u TSC=%u TFI=%d USF=%d\n", trx_no, m_bts.trx[trx_no].arfcn & ~ARFCN_FLAG_MASK, ts_no, ta, tsc, tbf ? tbf->tfi() : -1, usf); plen = Encoding::write_immediate_assignment( &m_bts.trx[trx_no].pdch[ts_no], tbf, bv, false, rip->ra, Fn, ta, usf, false, sb_fn, m_bts.alpha, m_bts.gamma, -1, rip->burst_type); do_rate_ctr_inc(CTR_IMMEDIATE_ASSIGN_UL_TBF); } if (plen >= 0) pcu_l1if_tx_agch(bv, plen); else rc = plen; bitvec_free(bv); return rc; } /* PTCCH/U sub-slot / frame-number mapping (see 3GPP TS 45.002, table 6) */ static uint32_t ptcch_slot_map[PTCCH_TAI_NUM] = { 12, 38, 64, 90, 116, 142, 168, 194, 220, 246, 272, 298, 324, 350, 376, 402, }; int BTS::rcv_ptcch_rach(const struct rach_ind_params *rip) { uint32_t fn416 = rfn_to_fn(rip->rfn) % 416; struct gprs_rlcmac_bts *bts = bts_data(); struct gprs_rlcmac_pdch *pdch; uint8_t ss; send_gsmtap_rach(PCU_GSMTAP_C_UL_PTCCH, GSMTAP_CHANNEL_PTCCH, rip); /* Prevent buffer overflow */ if (rip->trx_nr >= ARRAY_SIZE(bts->trx) || rip->ts_nr >= 8) { LOGP(DRLCMAC, LOGL_ERROR, "(TRX=%u TS=%u RFN=%u) Rx malformed " "RACH.ind (PTCCH/U)\n", rip->trx_nr, rip->ts_nr, rip->rfn); return -EINVAL; } /* Make sure PDCH time-slot is enabled */ pdch = &bts->trx[rip->trx_nr].pdch[rip->ts_nr]; if (!pdch->m_is_enabled) { LOGP(DRLCMAC, LOGL_NOTICE, "(TRX=%u TS=%u RFN=%u) Rx RACH.ind (PTCCH/U) " "for inactive PDCH\n", rip->trx_nr, rip->ts_nr, rip->rfn); return -EAGAIN; } /* Convert TDMA frame-number to PTCCH/U sub-slot number */ for (ss = 0; ss < PTCCH_TAI_NUM; ss++) if (ptcch_slot_map[ss] == fn416) break; if (ss == PTCCH_TAI_NUM) { LOGP(DRLCMAC, LOGL_ERROR, "(TRX=%u TS=%u RFN=%u) Failed to map " "PTCCH/U sub-slot\n", rip->trx_nr, rip->ts_nr, rip->rfn); return -ENODEV; } /* Apply the new Timing Advance value */ LOGP(DRLCMAC, LOGL_INFO, "Continuous Timing Advance update " "for TAI %u, new TA is %u\n", ss, qta2ta(rip->qta)); pdch->update_ta(ss, qta2ta(rip->qta)); return 0; } void BTS::snd_dl_ass(gprs_rlcmac_tbf *tbf, bool poll, uint16_t pgroup) { uint8_t trx_no = tbf->trx->trx_no; uint8_t ts_no = tbf->first_ts; int plen; LOGPTBF(tbf, LOGL_INFO, "TX: START Immediate Assignment Downlink (PCH)\n"); bitvec *immediate_assignment = bitvec_alloc(22, tall_pcu_ctx); /* without plen */ bitvec_unhex(immediate_assignment, DUMMY_VEC); /* standard '2B'O padding */ /* use request reference that has maximum distance to current time, * so the assignment will not conflict with possible RACH requests. */ LOGP(DRLCMAC, LOGL_DEBUG, " - TRX=%d (%d) TS=%d TA=%d pollFN=%d\n", trx_no, tbf->trx->arfcn, ts_no, tbf->ta(), poll ? tbf->poll_fn : -1); plen = Encoding::write_immediate_assignment(&m_bts.trx[trx_no].pdch[ts_no], tbf, immediate_assignment, true, 125, (tbf->pdch[ts_no]->last_rts_fn + 21216) % GSM_MAX_FN, tbf->ta(), 7, poll, tbf->poll_fn, m_bts.alpha, m_bts.gamma, -1, GSM_L1_BURST_TYPE_ACCESS_0); if (plen >= 0) { do_rate_ctr_inc(CTR_IMMEDIATE_ASSIGN_DL_TBF); pcu_l1if_tx_pch(immediate_assignment, plen, pgroup); } bitvec_free(immediate_assignment); } /* return maximum DL CS supported by BTS and allowed by VTY */ uint8_t BTS::max_cs_dl(void) const { return m_max_cs_dl; } /* return maximum UL CS supported by BTS and allowed by VTY */ uint8_t BTS::max_cs_ul(void) const { return m_max_cs_ul; } /* return maximum DL MCS supported by BTS and allowed by VTY */ uint8_t BTS::max_mcs_dl(void) const { return m_max_mcs_dl; } /* return maximum UL MCS supported by BTS and allowed by VTY */ uint8_t BTS::max_mcs_ul(void) const { return m_max_mcs_ul; } /* Set maximum DL CS supported by BTS and allowed by VTY */ void BTS::set_max_cs_dl(uint8_t cs_dl) { m_max_cs_dl = cs_dl; } /* Set maximum UL CS supported by BTS and allowed by VTY */ void BTS::set_max_cs_ul(uint8_t cs_ul) { m_max_cs_ul = cs_ul; } /* Set maximum DL MCS supported by BTS and allowed by VTY */ void BTS::set_max_mcs_dl(uint8_t mcs_dl) { m_max_mcs_dl = mcs_dl; } /* Set maximum UL MCS supported by BTS and allowed by VTY */ void BTS::set_max_mcs_ul(uint8_t mcs_ul) { m_max_mcs_ul = mcs_ul; } GprsMs *BTS::ms_alloc(uint8_t ms_class, uint8_t egprs_ms_class) { GprsMs *ms; ms = ms_store().create_ms(); ms->set_timeout(osmo_tdef_get(m_bts.T_defs_pcu, -2030, OSMO_TDEF_S, -1)); ms->set_ms_class(ms_class); ms->set_egprs_ms_class(egprs_ms_class); return ms; } /* update TA based on TA provided by PH-DATA-IND */ void update_tbf_ta(struct gprs_rlcmac_ul_tbf *tbf, int8_t ta_delta) { int16_t ta_adj; uint8_t ta_target; if (ta_delta) { /* adjust TA based on TA provided by PH-DATA-IND */ ta_adj = tbf->ta() + ta_delta; /* limit target TA in range 0..63 bits */ ta_target = ta_limit(ta_adj); LOGP(DL1IF, LOGL_INFO, "PH-DATA-IND is updating TLLI=0x%08x: TA %u -> %u on " "TRX = %d, TS = %d, FN = %d\n", tbf->tlli(), tbf->ta(), ta_target, tbf->trx->trx_no , tbf->poll_ts, tbf->poll_fn); tbf->set_ta(ta_target); } } /* set TA based on TA provided by PH-RA-IND */ void set_tbf_ta(struct gprs_rlcmac_ul_tbf *tbf, uint8_t ta) { uint8_t ta_target; if (tbf->ta() != ta) { /* limit target TA in range 0..63 bits */ ta_target = ta_limit(ta); LOGP(DL1IF, LOGL_INFO, "PH-RA-IND is updating TLLI=0x%08x: TA %u -> %u on " "TRX = %d, TS = %d, FN = %d\n", tbf->tlli(), tbf->ta(), ta_target, tbf->trx->trx_no , tbf->poll_ts, tbf->poll_fn); tbf->set_ta(ta_target); } } void bts_update_tbf_ta(const char *p, uint32_t fn, uint8_t trx_no, uint8_t ts, int8_t ta, bool is_rach) { struct gprs_rlcmac_ul_tbf *tbf = bts_main_data()->bts->ul_tbf_by_poll_fn(fn, trx_no, ts); if (!tbf) LOGP(DL1IF, LOGL_DEBUG, "[%s] update TA = %u ignored due to " "unknown UL TBF on TRX = %d, TS = %d, FN = %d\n", p, ta, trx_no, ts, fn); else { /* we need to distinguish TA information provided by L1 * from PH-DATA-IND and PHY-RA-IND so that we can properly * update TA for given TBF */ if (is_rach) set_tbf_ta(tbf, (uint8_t)ta); else update_tbf_ta(tbf, ta); } } void gprs_rlcmac_trx::reserve_slots(enum gprs_rlcmac_tbf_direction dir, uint8_t slots) { unsigned i; for (i = 0; i < ARRAY_SIZE(pdch); i += 1) if (slots & (1 << i)) pdch[i].reserve(dir); } void gprs_rlcmac_trx::unreserve_slots(enum gprs_rlcmac_tbf_direction dir, uint8_t slots) { unsigned i; for (i = 0; i < ARRAY_SIZE(pdch); i += 1) if (slots & (1 << i)) pdch[i].unreserve(dir); } void bts_set_max_cs(struct gprs_rlcmac_bts *bts, uint8_t cs_dl, uint8_t cs_ul) { int i; bts->vty.max_cs_dl = cs_dl; cs_dl = 0; for (i = bts->vty.max_cs_dl - 1; i >= 0; i--) { if (bts->cs_mask & (1 << i)) { cs_dl = i + 1; break; } } bts->vty.max_cs_ul = cs_ul; cs_ul = 0; for (i = bts->vty.max_cs_ul - 1; i >= 0; i--) { if (bts->cs_mask & (1 << i)) { cs_ul = i + 1; break; } } LOGP(DRLCMAC, LOGL_DEBUG, "New max CS: DL=%u UL=%u\n", cs_dl, cs_ul); bts->bts->set_max_cs_dl(cs_dl); bts->bts->set_max_cs_ul(cs_ul); } void bts_set_max_mcs(struct gprs_rlcmac_bts *bts, uint8_t mcs_dl, uint8_t mcs_ul) { int i; bts->vty.max_mcs_dl = mcs_dl; mcs_dl = 0; for (i = bts->vty.max_mcs_dl - 1; i >= 0; i--) { if (bts->mcs_mask & (1 << i)) { mcs_dl = i + 1; break; } } bts->vty.max_mcs_ul = mcs_ul; mcs_ul = 0; for (i = bts->vty.max_mcs_ul - 1; i >= 0; i--) { if (bts->mcs_mask & (1 << i)) { mcs_ul = i + 1; break; } } LOGP(DRLCMAC, LOGL_DEBUG, "New max MCS: DL=%u UL=%u\n", mcs_dl, mcs_ul); bts->bts->set_max_mcs_dl(mcs_dl); bts->bts->set_max_mcs_ul(mcs_ul); }