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Harald Welte gerrit-no-reply at lists.osmocom.orgHarald Welte has submitted this change and it was merged. Change subject: Handle Timing Advance IE properly ...................................................................... Handle Timing Advance IE properly Move writing Timing Advance IE and Timing Advance Index into separate functions to simplify adding PTCCH support. This also fixes previous incorrect (and unused) code for writing Packet TA IE which has not set TS for TA. Change-Id: I786bf7fc999d401cc3d9e7f1e7a1fba953b5d458 Related: OS#1545 --- M src/encoding.cpp 1 file changed, 43 insertions(+), 31 deletions(-) Approvals: Harald Welte: Looks good to me, approved Jenkins Builder: Verified diff --git a/src/encoding.cpp b/src/encoding.cpp index 7d3fa14..fb80eeb 100644 --- a/src/encoding.cpp +++ b/src/encoding.cpp @@ -35,6 +35,43 @@ #include <errno.h> #include <string.h> +/* { 0 | 1 < TIMING_ADVANCE_INDEX : bit (4) > } */ +static inline bool write_tai(bitvec *dest, unsigned& wp, int8_t tai) +{ + if (tai < 0) { /* No TIMING_ADVANCE_INDEX: */ + bitvec_write_field(dest, wp, 0, 1); + return false; + } + /* TIMING_ADVANCE_INDEX: */ + bitvec_write_field(dest, wp, 1, 1); + bitvec_write_field(dest, wp, tai, 4); + return true; +} + +/* { 0 | 1 < TIMING_ADVANCE_VALUE : bit (6) > } */ +static inline void write_ta(bitvec *dest, unsigned& wp, int8_t ta) +{ + if (ta < 0) /* No TIMING_ADVANCE_VALUE: */ + bitvec_write_field(dest, wp, 0, 1); + else { /* TIMING_ADVANCE_VALUE: */ + bitvec_write_field(dest, wp, 1, 1); + bitvec_write_field(dest, wp, ta, 6); + } +} + +/* 3GPP TS 44.060 § 12.12: + { 0 | 1 < TIMING_ADVANCE_VALUE : bit (6) > } + { 0 | 1 < TIMING_ADVANCE_INDEX : bit (4) > + < TIMING_ADVANCE_TIMESLOT_NUMBER : bit (3) > } + */ +static inline void write_ta_ie(bitvec *dest, unsigned& wp, + int8_t ta, int8_t tai, uint8_t ts) +{ + write_ta(dest, wp, ta); + if (write_tai(dest, wp, tai)) /* TIMING_ADVANCE_TIMESLOT_NUMBER: */ + bitvec_write_field(dest, wp, ts, 3); +} + static int write_ia_rest_downlink( gprs_rlcmac_dl_tbf *tbf, bitvec * dest, unsigned& wp, @@ -62,12 +99,7 @@ bitvec_write_field(dest, wp,gamma,5); // GAMMA power control parameter bitvec_write_field(dest, wp,polling,1); // Polling Bit bitvec_write_field(dest, wp, ta_valid, 1); // N. B: NOT related to TAI! - if (ta_idx < 0) { - bitvec_write_field(dest, wp,0x0,1); // switch TIMING_ADVANCE_INDEX = off - } else { - bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_INDEX = on - bitvec_write_field(dest, wp,ta_idx,4); // TIMING_ADVANCE_INDEX - } + write_tai(dest, wp, ta_idx); if (polling) { bitvec_write_field(dest, wp,0x1,1); // TBF Starting TIME present bitvec_write_field(dest, wp,(fn / (26 * 51)) % 32,5); // T1' @@ -110,12 +142,7 @@ } else bitvec_write_field(dest, wp,0x0,1); // ALPHA = not present bitvec_write_field(dest, wp,gamma,5); // GAMMA power control parameter - if (ta_idx < 0) { - bitvec_write_field(dest, wp,0x0,1); // switch TIMING_ADVANCE_INDEX = off - } else { - bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_INDEX = on - bitvec_write_field(dest, wp,ta_idx,4); // TIMING_ADVANCE_INDEX - } + write_tai(dest, wp, ta_idx); bitvec_write_field(dest, wp, 1, 1); // TBF_STARTING_TIME_FLAG bitvec_write_field(dest, wp,(fn / (26 * 51)) % 32,5); // T1' bitvec_write_field(dest, wp,fn % 51,6); // T3 @@ -311,6 +338,8 @@ // TODO We should use our implementation of encode RLC/MAC Control messages. unsigned wp = 0; uint8_t ts; + /* timeslot assigned for the Continuous Timing Advance procedure */ + uint8_t ta_ts = 0; /* FIXME: supply it as parameter from caller */ bitvec_write_field(dest, wp,0x1,2); // Payload Type bitvec_write_field(dest, wp,0x0,2); // Uplink block with TDMA framenumber (N+13) @@ -334,15 +363,7 @@ bitvec_write_field(dest, wp,0x0,1); // Message escape bitvec_write_field(dest, wp,tbf->current_cs().to_num()-1, 2); // CHANNEL_CODING_COMMAND bitvec_write_field(dest, wp,0x1,1); // TLLI_BLOCK_CHANNEL_CODING - bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_VALUE = on - bitvec_write_field(dest, wp,tbf->ta(),6); // TIMING_ADVANCE_VALUE - if (ta_idx < 0) { - bitvec_write_field(dest, wp,0x0,1); // switch TIMING_ADVANCE_INDEX = off - } else { - bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_INDEX = on - bitvec_write_field(dest, wp,ta_idx,4); // TIMING_ADVANCE_INDEX - } - + write_ta_ie(dest, wp,tbf->ta(), ta_idx, ta_ts); } else { /* EPGRS */ unsigned int ws_enc = (tbf->m_window.ws() - 64) / 32; bitvec_write_field(dest, wp,0x1,1); // Message escape @@ -357,16 +378,7 @@ bitvec_write_field(dest, wp,0x0,1); // No ARAC RETRANSMISSION REQUEST bitvec_write_field(dest, wp,0x1,1); // TLLI_BLOCK_CHANNEL_CODING bitvec_write_field(dest, wp,0x0,1); // No BEP_PERIOD2 - - bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_VALUE = on - bitvec_write_field(dest, wp,tbf->ta(),6); // TIMING_ADVANCE_VALUE - if (ta_idx < 0) { - bitvec_write_field(dest, wp,0x0,1); // switch TIMING_ADVANCE_INDEX = off - } else { - bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_INDEX = on - bitvec_write_field(dest, wp,ta_idx,4); // TIMING_ADVANCE_INDEX - } - + write_ta_ie(dest, wp,tbf->ta(), ta_idx, ta_ts); bitvec_write_field(dest, wp,0x0,1); // No Packet Extended Timing Advance } -- To view, visit https://gerrit.osmocom.org/552 To unsubscribe, visit https://gerrit.osmocom.org/settings Gerrit-MessageType: merged Gerrit-Change-Id: I786bf7fc999d401cc3d9e7f1e7a1fba953b5d458 Gerrit-PatchSet: 8 Gerrit-Project: osmo-pcu Gerrit-Branch: master Gerrit-Owner: Max <msuraev at sysmocom.de> Gerrit-Reviewer: Harald Welte <laforge at gnumonks.org> Gerrit-Reviewer: Holger Freyther <holger at freyther.de> Gerrit-Reviewer: Jenkins Builder Gerrit-Reviewer: Max <msuraev at sysmocom.de>