| /* |
| * 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 <http://www.gnu.org/licenses/>. |
| * |
| */ |
| |
| #include <bts.h> |
| #include <poll_controller.h> |
| #include <tbf.h> |
| #include <tbf_ul.h> |
| #include <encoding.h> |
| #include <decoding.h> |
| #include <rlc.h> |
| #include <pcu_l1_if.h> |
| #include <gprs_ms.h> |
| #include <gprs_rlcmac.h> |
| #include <gprs_debug.h> |
| #include <cxx_linuxlist.h> |
| #include <pdch.h> |
| |
| extern "C" { |
| #include <osmocom/core/talloc.h> |
| #include <osmocom/core/msgb.h> |
| #include <osmocom/core/stats.h> |
| #include <osmocom/gsm/protocol/gsm_04_08.h> |
| #include <osmocom/gsm/gsm_utils.h> |
| #include <osmocom/gsm/gsm48.h> |
| #include <osmocom/core/gsmtap_util.h> |
| #include <osmocom/core/application.h> |
| #include <osmocom/core/bitvec.h> |
| #include <osmocom/core/gsmtap.h> |
| #include <osmocom/core/logging.h> |
| #include <osmocom/core/utils.h> |
| } |
| |
| #include <errno.h> |
| #include <string.h> |
| |
| #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, const uint8_t *mi, uint8_t mi_len) |
| { |
| uint8_t l, trx, ts, any_tbf = 0; |
| struct gprs_rlcmac_tbf *tbf; |
| LListHead<gprs_rlcmac_tbf> *pos; |
| uint8_t slot_mask[8]; |
| int8_t first_ts; /* must be signed */ |
| |
| LListHead<gprs_rlcmac_tbf> *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_mi_name(mi, mi_len)); |
| |
| /* 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, mi_len)) |
| 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<gprs_rlcmac_tbf> *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<gprs_rlcmac_tbf> *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; |
| } |
| |
| /* 3GPP TS 44.060: |
| * Table 11.2.5.3: PACKET CHANNEL REQUEST |
| * Table 11.2.5a.3: EGPRS PACKET CHANNEL REQUEST |
| * Both GPRS and EGPRS use same MultislotClass coding, but since use of PCCCH 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 inline uint8_t egprs_mslot_class_from_ra(uint16_t ra, bool is_11bit) |
| { |
| if (is_11bit) |
| return ((ra & 0x3e0) >> 5) + 1; |
| |
| /* set EGPRS 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); |
| uint8_t egprs_ms_class = egprs_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, egprs_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, uint16_t pgroup) |
| { |
| 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, pgroup); |
| } |
| |
| 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); |
| } |