/* * 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 #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)) 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, }; 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_pollController(*this) , m_sba(*this) , m_ms_store(this) { memset(&m_bts, 0, sizeof(m_bts)); m_bts.bts = this; m_bts.app_info = NULL; m_bts.dl_tbf_preemptive_retransmission = true; m_bts.T_defs_bts = T_defs_bts; m_bts.T_defs_pcu = T_defs_pcu; osmo_tdefs_reset(m_bts.T_defs_bts); osmo_tdefs_reset(m_bts.T_defs_pcu); /* initialize back pointers */ for (size_t trx_no = 0; trx_no < ARRAY_SIZE(m_bts.trx); ++trx_no) { struct gprs_rlcmac_trx *trx = &m_bts.trx[trx_no]; trx->trx_no = trx_no; trx->bts = this; 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; } } /* 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()); 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, uint8_t *identity_lv) { 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 }; LOGP(DRLCMAC, LOGL_INFO, "Add RR paging: chan-needed=%d MI=%s\n", chan_needed, osmo_hexdump(identity_lv + 1, identity_lv[0])); /* 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, identity_lv)) 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(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) { 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_send(m_bts.gsmtap, arfcn, ts_no, channel, 0, fn, 0, 0, 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); } /* * Search for free TFI and return TFI, TRX. * This method returns the first TFI that is currently not used in any PDCH of * a TRX. The first TRX that contains such an TFI is returned. Negative values * indicate errors. */ int BTS::tfi_find_free(enum gprs_rlcmac_tbf_direction dir, uint8_t *_trx, int8_t use_trx) const { const struct gprs_rlcmac_pdch *pdch; uint32_t free_tfis; bool has_pdch = false; uint8_t trx_from, trx_to, trx, ts, tfi; 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++) { bool trx_has_pdch = false; free_tfis = NO_FREE_TFI; for (ts = 0; ts < 8; ts++) { pdch = &m_bts.trx[trx].pdch[ts]; if (!pdch->is_enabled()) continue; free_tfis &= ~pdch->assigned_tfi(dir); trx_has_pdch = true; has_pdch = true; } if (trx_has_pdch && free_tfis) break; free_tfis = 0; } if (!has_pdch) { LOGP(DRLCMAC, LOGL_NOTICE, "No PDCH available.\n"); return -EINVAL; } if (!free_tfis) { LOGP(DRLCMAC, LOGL_NOTICE, "No TFI available (suggested TRX: %d).\n", use_trx); return -EBUSY; } LOGP(DRLCMAC, LOGL_DEBUG, "Searching for first unallocated TFI: TRX=%d\n", trx); /* find the first */ for (tfi = 0; tfi < 32; tfi++) { if (free_tfis & 1 << tfi) break; } OSMO_ASSERT(tfi < 32); LOGP(DRLCMAC, LOGL_DEBUG, " Found TFI=%d.\n", tfi); *_trx = trx; return 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; } static inline uint16_t mslot_class_from_ra(uint16_t ra, bool is_11bit) { if (is_11bit) return (ra & 0x3e0) >> 5; /* set multislot class to 0 for 8-bit RACH, since we don't know it yet */ return 0; } static inline uint16_t priority_from_ra(uint16_t ra, bool is_11bit) { if (is_11bit) return (ra & 0x18) >> 3; return 0; } static inline bool is_single_block(bool force_two_phase, uint16_t ra, enum ph_burst_type burst_type, bool is_11bit) { bool sb = false; if ((ra & 0xf8) == 0x70) LOGP(DRLCMAC, LOGL_DEBUG, "MS requests single block allocation\n"); else if (force_two_phase) LOGP(DRLCMAC, LOGL_DEBUG, "MS requests single phase access, but we force two phase access [RACH is %s bit]\n", is_11bit ? "11" : "8"); switch(burst_type) { case GSM_L1_BURST_TYPE_ACCESS_0: if (is_11bit) { LOGP(DRLCMAC, LOGL_ERROR, "Error: GPRS 11 bit RACH not supported\n"); return false; } if ((ra & 0xf8) == 0x70) return true; if (force_two_phase) return true; break; case GSM_L1_BURST_TYPE_ACCESS_1: /* deliberate fall-through */ case GSM_L1_BURST_TYPE_ACCESS_2: if (is_11bit) { if (!(ra & (1 << 10))) { if (force_two_phase) return true; return false; } return true; } LOGP(DRLCMAC, LOGL_ERROR, "Unexpected RACH burst type %u for 8-bit RACH\n", burst_type); break; case GSM_L1_BURST_TYPE_NONE: LOGP(DRLCMAC, LOGL_ERROR, "PCU has not received burst type from BTS\n"); break; default: LOGP(DRLCMAC, LOGL_ERROR, "Unexpected RACH burst type %u for %s-bit RACH\n", burst_type, is_11bit ? "11" : "8"); } return sb; } int BTS::rcv_rach(uint16_t ra, uint32_t Fn, int16_t qta, bool is_11bit, enum ph_burst_type burst_type) { struct gprs_rlcmac_ul_tbf *tbf = NULL; uint8_t trx_no, ts_no = 0; uint8_t sb = 0; uint32_t sb_fn = 0; int rc = 0; int plen; uint8_t usf = 7; uint8_t tsc = 0, ta = qta2ta(qta); uint16_t ms_class = mslot_class_from_ra(ra, is_11bit); bool failure = false; rach_frame(); if (is_11bit) rach_frame_11bit(); /* Determine full frame number */ Fn = rfn_to_fn(Fn); send_gsmtap(PCU_GSMTAP_C_UL_RACH, true, 0, ts_no, GSMTAP_CHANNEL_RACH, Fn, (uint8_t*)&ra, is_11bit ? 2 : 1); LOGP(DRLCMAC, LOGL_DEBUG, "MS requests UL TBF on RACH, " "so we provide one: ra=0x%02x Fn=%u qta=%d is_11bit=%d:\n", ra, Fn, qta, is_11bit); sb = is_single_block(m_bts.force_two_phase, ra, burst_type, is_11bit); if (sb) { rc = sba()->alloc(&trx_no, &ts_no, &sb_fn, ta); if (rc < 0) { failure = true; LOGP(DRLCMAC, LOGL_NOTICE, "No PDCH resource for " "single block allocation." "sending Immediate " "Assignment Uplink (AGCH) reject\n"); } else { tsc = m_bts.trx[trx_no].pdch[ts_no].tsc; LOGP(DRLCMAC, LOGL_DEBUG, "RX: [PCU <- BTS] RACH " " qbit-ta=%d ra=0x%02x, Fn=%d (%d,%d,%d)," " SBFn=%d\n", qta, ra, Fn, (Fn / (26 * 51)) % 32, Fn % 51, Fn % 26, sb_fn); LOGP(DRLCMAC, LOGL_INFO, "TX: Immediate Assignment " "Uplink (AGCH)\n"); } } else { // Create new TBF /* FIXME: Copy and paste with other routines.. */ tbf = tbf_alloc_ul_tbf(&m_bts, NULL, -1, 0, ms_class, true); if (!tbf) { LOGP(DRLCMAC, LOGL_NOTICE, "No PDCH resource sending " "Immediate Assignment Uplink (AGCH) " "reject\n"); rc = -EBUSY; failure = true; } else { 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); LOGPTBF(tbf, LOGL_DEBUG, "[UPLINK] START\n"); LOGPTBF(tbf, LOGL_DEBUG, "RX: [PCU <- BTS] RACH " "qbit-ta=%d ra=0x%02x, Fn=%d " " (%d,%d,%d)\n", qta, ra, Fn, (Fn / (26 * 51)) % 32, Fn % 51, Fn % 26); LOGPTBF(tbf, LOGL_INFO, "TX: START Immediate Assignment Uplink (AGCH)\n"); trx_no = tbf->trx->trx_no; ts_no = tbf->first_ts; usf = tbf->m_usf[ts_no]; tsc = tbf->tsc(); } } bitvec *immediate_assignment = bitvec_alloc(22, tall_pcu_ctx) /* without plen */; bitvec_unhex(immediate_assignment, "2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); if (failure) { plen = Encoding::write_immediate_assignment_reject( immediate_assignment, ra, Fn, burst_type); immediate_assignment_reject(); } else { LOGP(DRLCMAC, LOGL_DEBUG, " - TRX=%d (%d) TS=%d TA=%d TSC=%d TFI=%d USF=%d\n", trx_no, m_bts.trx[trx_no].arfcn, ts_no, ta, tsc, tbf ? tbf->tfi() : -1, usf); // N. B: if tbf == NULL then SBA is used for Imm. Ass. below plen = Encoding::write_immediate_assignment(tbf, immediate_assignment, false, ra, Fn, ta, m_bts.trx[trx_no].arfcn, ts_no, tsc, usf, false, sb_fn, m_bts.alpha, m_bts.gamma, -1, burst_type); } if (plen >= 0) { immediate_assignment_ul_tbf(); pcu_l1if_tx_agch(immediate_assignment, plen); } bitvec_free(immediate_assignment); 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(uint8_t trx_nr, uint8_t ts_nr, uint32_t fn, int16_t qta) { struct gprs_rlcmac_bts *bts = bts_data(); struct gprs_rlcmac_pdch *pdch; uint32_t fn416 = fn % 416; uint8_t ss; /* Prevent buffer overflow */ if (trx_nr >= ARRAY_SIZE(bts->trx) || ts_nr >= 8) { LOGP(DRLCMAC, LOGL_ERROR, "Malformed RACH.ind message " "(TRX=%u TS=%u FN=%u)\n", trx_nr, ts_nr, fn); return -EINVAL; } /* Make sure PDCH time-slot is enabled */ pdch = &bts->trx[trx_nr].pdch[ts_nr]; if (!pdch->m_is_enabled) { LOGP(DRLCMAC, LOGL_NOTICE, "Rx PTCCH RACH.ind for inactive PDCH " "(TRX=%u TS=%u FN=%u)\n", trx_nr, ts_nr, fn); 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, "Failed to map PTCCH/U sub-slot for fn=%u\n", fn); 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(qta)); pdch->update_ta(ss, qta2ta(qta)); return 0; } void BTS::snd_dl_ass(gprs_rlcmac_tbf *tbf, bool poll, const char *imsi) { int plen; unsigned int ts = tbf->first_ts; 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, "2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); /* 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", tbf->trx->trx_no, tbf->trx->arfcn, ts, tbf->ta(), poll ? tbf->poll_fn : -1); plen = Encoding::write_immediate_assignment(tbf, immediate_assignment, true, 125, (tbf->pdch[ts]->last_rts_fn + 21216) % GSM_MAX_FN, tbf->ta(), tbf->trx->arfcn, ts, tbf->tsc(), 7, poll, tbf->poll_fn, m_bts.alpha, m_bts.gamma, -1, GSM_L1_BURST_TYPE_ACCESS_0); if (plen >= 0) { immediate_assignment_dl_tbf(); pcu_l1if_tx_pch(immediate_assignment, plen, imsi); } bitvec_free(immediate_assignment); } 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); }