1042 lines
37 KiB
C++
1042 lines
37 KiB
C++
/* encoding.cpp
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*
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* Copyright (C) 2012 Ivan Klyuchnikov
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* Copyright (C) 2012 Andreas Eversberg <jolly@eversberg.eu>
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* Copyright (C) 2013 by Holger Hans Peter Freyther
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*/
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#include <encoding.h>
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#include <gprs_rlcmac.h>
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#include <bts.h>
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#include <tbf.h>
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#include <gprs_debug.h>
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#include <errno.h>
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#include <string.h>
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// GSM 04.08 9.1.18 Immediate assignment
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int Encoding::write_immediate_assignment(
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struct gprs_rlcmac_bts *bts,
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bitvec * dest, uint8_t downlink, uint8_t ra,
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uint32_t ref_fn, uint8_t ta, uint16_t arfcn, uint8_t ts, uint8_t tsc,
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uint8_t tfi, uint8_t usf, uint32_t tlli,
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uint8_t polling, uint32_t fn, uint8_t single_block, uint8_t alpha,
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uint8_t gamma, int8_t ta_idx)
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{
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unsigned wp = 0;
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uint8_t plen;
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bitvec_write_field(dest, wp,0x0,4); // Skip Indicator
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bitvec_write_field(dest, wp,0x6,4); // Protocol Discriminator
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bitvec_write_field(dest, wp,0x3F,8); // Immediate Assignment Message Type
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// 10.5.2.25b Dedicated mode or TBF
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bitvec_write_field(dest, wp,0x0,1); // spare
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bitvec_write_field(dest, wp,0x0,1); // TMA : Two-message assignment: No meaning
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bitvec_write_field(dest, wp,downlink,1); // Downlink : Downlink assignment to mobile in packet idle mode
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bitvec_write_field(dest, wp,0x1,1); // T/D : TBF or dedicated mode: this message assigns a Temporary Block Flow (TBF).
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bitvec_write_field(dest, wp,0x0,4); // Page Mode
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// GSM 04.08 10.5.2.25a Packet Channel Description
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bitvec_write_field(dest, wp,0x1,5); // Channel type
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bitvec_write_field(dest, wp,ts,3); // TN
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bitvec_write_field(dest, wp,tsc,3); // TSC
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bitvec_write_field(dest, wp,0x0,3); // non-hopping RF channel configuraion
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bitvec_write_field(dest, wp,arfcn,10); // ARFCN
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//10.5.2.30 Request Reference
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bitvec_write_field(dest, wp,ra,8); // RA
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bitvec_write_field(dest, wp,(ref_fn / (26 * 51)) % 32,5); // T1'
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bitvec_write_field(dest, wp,ref_fn % 51,6); // T3
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bitvec_write_field(dest, wp,ref_fn % 26,5); // T2
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// 10.5.2.40 Timing Advance
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bitvec_write_field(dest, wp,0x0,2); // spare
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bitvec_write_field(dest, wp,ta,6); // Timing Advance value
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// No mobile allocation in non-hopping systems.
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// A zero-length LV. Just write L=0.
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bitvec_write_field(dest, wp,0,8);
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if ((wp % 8)) {
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LOGP(DRLCMACUL, LOGL_ERROR, "Length of IMM.ASS without rest "
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"octets is not multiple of 8 bits, PLEASE FIX!\n");
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exit (0);
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}
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plen = wp / 8;
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if (downlink)
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{
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// GSM 04.08 10.5.2.16 IA Rest Octets
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bitvec_write_field(dest, wp, 3, 2); // "HH"
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bitvec_write_field(dest, wp, 1, 2); // "01" Packet Downlink Assignment
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bitvec_write_field(dest, wp,tlli,32); // TLLI
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bitvec_write_field(dest, wp,0x1,1); // switch TFI : on
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bitvec_write_field(dest, wp,tfi,5); // TFI
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bitvec_write_field(dest, wp,0x0,1); // RLC acknowledged mode
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if (alpha) {
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bitvec_write_field(dest, wp,0x1,1); // ALPHA = present
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bitvec_write_field(dest, wp,alpha,4); // ALPHA
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} else {
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bitvec_write_field(dest, wp,0x0,1); // ALPHA = not present
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}
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bitvec_write_field(dest, wp,gamma,5); // GAMMA power control parameter
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bitvec_write_field(dest, wp,polling,1); // Polling Bit
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bitvec_write_field(dest, wp,!polling,1); // TA_VALID ???
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if (ta_idx < 0) {
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bitvec_write_field(dest, wp,0x0,1); // switch TIMING_ADVANCE_INDEX = off
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} else {
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bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_INDEX = on
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bitvec_write_field(dest, wp,ta_idx,4); // TIMING_ADVANCE_INDEX
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}
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if (polling) {
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bitvec_write_field(dest, wp,0x1,1); // TBF Starting TIME present
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bitvec_write_field(dest, wp,(fn / (26 * 51)) % 32,5); // T1'
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bitvec_write_field(dest, wp,fn % 51,6); // T3
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bitvec_write_field(dest, wp,fn % 26,5); // T2
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} else {
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bitvec_write_field(dest, wp,0x0,1); // TBF Starting TIME present
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}
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bitvec_write_field(dest, wp,0x0,1); // P0 not present
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// bitvec_write_field(dest, wp,0x1,1); // P0 not present
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// bitvec_write_field(dest, wp,0xb,4);
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}
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else
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{
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// GMS 04.08 10.5.2.37b 10.5.2.16
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bitvec_write_field(dest, wp, 3, 2); // "HH"
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bitvec_write_field(dest, wp, 0, 2); // "0" Packet Uplink Assignment
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if (single_block) {
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bitvec_write_field(dest, wp, 0, 1); // Block Allocation : Single Block Allocation
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if (alpha) {
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bitvec_write_field(dest, wp,0x1,1); // ALPHA = present
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bitvec_write_field(dest, wp,alpha,4); // ALPHA = present
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} else
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bitvec_write_field(dest, wp,0x0,1); // ALPHA = not present
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bitvec_write_field(dest, wp,gamma,5); // GAMMA power control parameter
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if (ta_idx < 0) {
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bitvec_write_field(dest, wp,0x0,1); // switch TIMING_ADVANCE_INDEX = off
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} else {
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bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_INDEX = on
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bitvec_write_field(dest, wp,ta_idx,4); // TIMING_ADVANCE_INDEX
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}
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bitvec_write_field(dest, wp, 1, 1); // TBF_STARTING_TIME_FLAG
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bitvec_write_field(dest, wp,(fn / (26 * 51)) % 32,5); // T1'
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bitvec_write_field(dest, wp,fn % 51,6); // T3
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bitvec_write_field(dest, wp,fn % 26,5); // T2
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} else {
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bitvec_write_field(dest, wp, 1, 1); // Block Allocation : Not Single Block Allocation
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bitvec_write_field(dest, wp, tfi, 5); // TFI_ASSIGNMENT Temporary Flow Identity
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bitvec_write_field(dest, wp, 0, 1); // POLLING
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bitvec_write_field(dest, wp, 0, 1); // ALLOCATION_TYPE: dynamic
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bitvec_write_field(dest, wp, usf, 3); // USF
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bitvec_write_field(dest, wp, 0, 1); // USF_GRANULARITY
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bitvec_write_field(dest, wp, 0, 1); // "0" power control: Not Present
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bitvec_write_field(dest, wp, bts->initial_cs_ul-1, 2); // CHANNEL_CODING_COMMAND
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bitvec_write_field(dest, wp, 1, 1); // TLLI_BLOCK_CHANNEL_CODING
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if (alpha) {
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bitvec_write_field(dest, wp,0x1,1); // ALPHA = present
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bitvec_write_field(dest, wp,alpha,4); // ALPHA
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} else
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bitvec_write_field(dest, wp,0x0,1); // ALPHA = not present
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bitvec_write_field(dest, wp,gamma,5); // GAMMA power control parameter
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/* note: there is no choise for TAI and no starting time */
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bitvec_write_field(dest, wp, 0, 1); // switch TIMING_ADVANCE_INDEX = off
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bitvec_write_field(dest, wp, 0, 1); // TBF_STARTING_TIME_FLAG
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}
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}
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return plen;
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}
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/* generate uplink assignment */
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void Encoding::write_packet_uplink_assignment(
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struct gprs_rlcmac_bts *bts,
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bitvec * dest, uint8_t old_tfi,
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uint8_t old_downlink, uint32_t tlli, uint8_t use_tlli,
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struct gprs_rlcmac_ul_tbf *tbf, uint8_t poll, uint8_t alpha,
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uint8_t gamma, int8_t ta_idx, int8_t use_egprs)
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{
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// TODO We should use our implementation of encode RLC/MAC Control messages.
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unsigned wp = 0;
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uint8_t ts;
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bitvec_write_field(dest, wp,0x1,2); // Payload Type
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bitvec_write_field(dest, wp,0x0,2); // Uplink block with TDMA framenumber (N+13)
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bitvec_write_field(dest, wp,poll,1); // Suppl/Polling Bit
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bitvec_write_field(dest, wp,0x0,3); // Uplink state flag
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bitvec_write_field(dest, wp,0xa,6); // MESSAGE TYPE
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bitvec_write_field(dest, wp,0x0,2); // Page Mode
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bitvec_write_field(dest, wp,0x0,1); // switch PERSIST_LEVEL: off
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if (use_tlli) {
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bitvec_write_field(dest, wp,0x2,2); // switch TLLI : on
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bitvec_write_field(dest, wp,tlli,32); // TLLI
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} else {
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bitvec_write_field(dest, wp,0x0,1); // switch TFI : on
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bitvec_write_field(dest, wp,old_downlink,1); // 0=UPLINK TFI, 1=DL TFI
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bitvec_write_field(dest, wp,old_tfi,5); // TFI
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}
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if (!use_egprs) {
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bitvec_write_field(dest, wp,0x0,1); // Message escape
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bitvec_write_field(dest, wp,tbf->current_cs().to_num()-1, 2); // CHANNEL_CODING_COMMAND
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bitvec_write_field(dest, wp,0x1,1); // TLLI_BLOCK_CHANNEL_CODING
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bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_VALUE = on
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bitvec_write_field(dest, wp,tbf->ta(),6); // TIMING_ADVANCE_VALUE
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if (ta_idx < 0) {
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bitvec_write_field(dest, wp,0x0,1); // switch TIMING_ADVANCE_INDEX = off
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} else {
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bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_INDEX = on
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bitvec_write_field(dest, wp,ta_idx,4); // TIMING_ADVANCE_INDEX
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}
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} else { /* EPGRS */
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unsigned int ws_enc = (tbf->m_window.ws() - 64) / 32;
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bitvec_write_field(dest, wp,0x1,1); // Message escape
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bitvec_write_field(dest, wp,0x0,2); // EGPRS message contents
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bitvec_write_field(dest, wp,0x0,1); // No CONTENTION_RESOLUTION_TLLI
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bitvec_write_field(dest, wp,0x0,1); // No COMPACT reduced MA
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bitvec_write_field(dest, wp,tbf->current_cs().to_num()-1, 4); // EGPRS Modulation and Coding IE
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bitvec_write_field(dest, wp,0x0,1); // No RESEGMENT
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bitvec_write_field(dest, wp,ws_enc,5); // EGPRS Window Size
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bitvec_write_field(dest, wp,0x0,1); // No Access Technologies Request
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bitvec_write_field(dest, wp,0x0,1); // No ARAC RETRANSMISSION REQUEST
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bitvec_write_field(dest, wp,0x1,1); // TLLI_BLOCK_CHANNEL_CODING
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bitvec_write_field(dest, wp,0x0,1); // No BEP_PERIOD2
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bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_VALUE = on
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bitvec_write_field(dest, wp,tbf->ta(),6); // TIMING_ADVANCE_VALUE
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if (ta_idx < 0) {
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bitvec_write_field(dest, wp,0x0,1); // switch TIMING_ADVANCE_INDEX = off
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} else {
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bitvec_write_field(dest, wp,0x1,1); // switch TIMING_ADVANCE_INDEX = on
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bitvec_write_field(dest, wp,ta_idx,4); // TIMING_ADVANCE_INDEX
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}
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bitvec_write_field(dest, wp,0x0,1); // No Packet Extended Timing Advance
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}
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#if 1
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bitvec_write_field(dest, wp,0x1,1); // Frequency Parameters information elements = present
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bitvec_write_field(dest, wp,tbf->tsc(),3); // Training Sequence Code (TSC)
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bitvec_write_field(dest, wp,0x0,2); // ARFCN = present
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bitvec_write_field(dest, wp,tbf->trx->arfcn,10); // ARFCN
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#else
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bitvec_write_field(dest, wp,0x0,1); // Frequency Parameters = off
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#endif
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bitvec_write_field(dest, wp,0x1,2); // Dynamic Allocation
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bitvec_write_field(dest, wp,0x0,1); // Extended Dynamic Allocation = off
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bitvec_write_field(dest, wp,0x0,1); // P0 = off
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bitvec_write_field(dest, wp,0x0,1); // USF_GRANULARITY
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bitvec_write_field(dest, wp,0x1,1); // switch TFI : on
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bitvec_write_field(dest, wp,tbf->tfi(),5);// TFI
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bitvec_write_field(dest, wp,0x0,1); //
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bitvec_write_field(dest, wp,0x0,1); // TBF Starting Time = off
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if (alpha || gamma) {
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bitvec_write_field(dest, wp,0x1,1); // Timeslot Allocation with Power Control
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bitvec_write_field(dest, wp,alpha,4); // ALPHA
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} else
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bitvec_write_field(dest, wp,0x0,1); // Timeslot Allocation
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for (ts = 0; ts < 8; ts++) {
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if (tbf->pdch[ts]) {
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bitvec_write_field(dest, wp,0x1,1); // USF_TN(i): on
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bitvec_write_field(dest, wp,tbf->m_usf[ts],3); // USF_TN(i)
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if (alpha || gamma)
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bitvec_write_field(dest, wp,gamma,5); // GAMMA power control parameter
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} else
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bitvec_write_field(dest, wp,0x0,1); // USF_TN(i): off
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}
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// bitvec_write_field(dest, wp,0x0,1); // Measurement Mapping struct not present
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}
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/* generate downlink assignment */
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void Encoding::write_packet_downlink_assignment(RlcMacDownlink_t * block,
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uint8_t old_tfi, uint8_t old_downlink, struct gprs_rlcmac_tbf *tbf,
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uint8_t poll, uint8_t alpha, uint8_t gamma, int8_t ta_idx, uint8_t ta_ts,
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bool use_egprs)
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{
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// Packet downlink assignment TS 44.060 11.2.7
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PDA_AdditionsR99_t *pda_r99;
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uint8_t tn;
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unsigned int ws_enc;
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block->PAYLOAD_TYPE = 0x1; // RLC/MAC control block that does not include the optional octets of the RLC/MAC control header
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block->RRBP = 0x0; // N+13
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block->SP = poll; // RRBP field is valid
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block->USF = 0x0; // Uplink state flag
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block->u.Packet_Downlink_Assignment.MESSAGE_TYPE = 0x2; // Packet Downlink Assignment
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block->u.Packet_Downlink_Assignment.PAGE_MODE = 0x0; // Normal Paging
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block->u.Packet_Downlink_Assignment.Exist_PERSISTENCE_LEVEL = 0x0; // PERSISTENCE_LEVEL: off
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block->u.Packet_Downlink_Assignment.ID.UnionType = 0x0; // TFI = on
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block->u.Packet_Downlink_Assignment.ID.u.Global_TFI.UnionType = old_downlink; // 0=UPLINK TFI, 1=DL TFI
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block->u.Packet_Downlink_Assignment.ID.u.Global_TFI.u.UPLINK_TFI = old_tfi; // TFI
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block->u.Packet_Downlink_Assignment.MAC_MODE = 0x0; // Dynamic Allocation
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block->u.Packet_Downlink_Assignment.RLC_MODE = 0x0; // RLC acknowledged mode
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block->u.Packet_Downlink_Assignment.CONTROL_ACK = tbf->was_releasing; // NW establishes no new DL TBF for the MS with running timer T3192
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block->u.Packet_Downlink_Assignment.TIMESLOT_ALLOCATION = 0; // timeslot(s)
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for (tn = 0; tn < 8; tn++) {
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if (tbf->pdch[tn])
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block->u.Packet_Downlink_Assignment.TIMESLOT_ALLOCATION |= 0x80 >> tn; // timeslot(s)
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}
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block->u.Packet_Downlink_Assignment.Packet_Timing_Advance.Exist_TIMING_ADVANCE_VALUE = 0x1; // TIMING_ADVANCE_VALUE = on
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block->u.Packet_Downlink_Assignment.Packet_Timing_Advance.TIMING_ADVANCE_VALUE = tbf->ta(); // TIMING_ADVANCE_VALUE
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if (ta_idx < 0) {
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block->u.Packet_Downlink_Assignment.Packet_Timing_Advance.Exist_IndexAndtimeSlot = 0x0; // TIMING_ADVANCE_INDEX = off
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} else {
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block->u.Packet_Downlink_Assignment.Packet_Timing_Advance.Exist_IndexAndtimeSlot = 0x1; // TIMING_ADVANCE_INDEX = on
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block->u.Packet_Downlink_Assignment.Packet_Timing_Advance.TIMING_ADVANCE_INDEX = ta_idx; // TIMING_ADVANCE_INDEX
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block->u.Packet_Downlink_Assignment.Packet_Timing_Advance.TIMING_ADVANCE_TIMESLOT_NUMBER = ta_ts; // TIMING_ADVANCE_TS
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}
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block->u.Packet_Downlink_Assignment.Exist_P0_and_BTS_PWR_CTRL_MODE = 0x0; // POWER CONTROL = off
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block->u.Packet_Downlink_Assignment.Exist_Frequency_Parameters = 0x1; // Frequency Parameters = on
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block->u.Packet_Downlink_Assignment.Frequency_Parameters.TSC = tbf->tsc(); // Training Sequence Code (TSC)
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block->u.Packet_Downlink_Assignment.Frequency_Parameters.UnionType = 0x0; // ARFCN = on
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block->u.Packet_Downlink_Assignment.Frequency_Parameters.u.ARFCN = tbf->trx->arfcn; // ARFCN
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block->u.Packet_Downlink_Assignment.Exist_DOWNLINK_TFI_ASSIGNMENT = 0x1; // DOWNLINK TFI ASSIGNMENT = on
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block->u.Packet_Downlink_Assignment.DOWNLINK_TFI_ASSIGNMENT = tbf->tfi(); // TFI
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block->u.Packet_Downlink_Assignment.Exist_Power_Control_Parameters = 0x1; // Power Control Parameters = on
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block->u.Packet_Downlink_Assignment.Power_Control_Parameters.ALPHA = alpha; // ALPHA
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for (tn = 0; tn < 8; tn++)
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{
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if (tbf->pdch[tn])
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{
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block->u.Packet_Downlink_Assignment.Power_Control_Parameters.Slot[tn].Exist = 0x1; // Slot[i] = on
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block->u.Packet_Downlink_Assignment.Power_Control_Parameters.Slot[tn].GAMMA_TN = gamma; // GAMMA_TN
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}
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else
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{
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block->u.Packet_Downlink_Assignment.Power_Control_Parameters.Slot[tn].Exist = 0x0; // Slot[i] = off
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}
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}
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block->u.Packet_Downlink_Assignment.Exist_TBF_Starting_Time = 0x0; // TBF Starting TIME = off
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|
block->u.Packet_Downlink_Assignment.Exist_Measurement_Mapping = 0x0; // Measurement_Mapping = off
|
|
if (!use_egprs) {
|
|
block->u.Packet_Downlink_Assignment.Exist_AdditionsR99 = 0x0; // AdditionsR99 = off
|
|
return;
|
|
}
|
|
|
|
ws_enc = (tbf->window()->ws() - 64) / 32;
|
|
|
|
block->u.Packet_Downlink_Assignment.Exist_AdditionsR99 = 0x1; // AdditionsR99 = on
|
|
pda_r99 = &block->u.Packet_Downlink_Assignment.AdditionsR99;
|
|
pda_r99->Exist_EGPRS_Params = 1;
|
|
pda_r99->EGPRS_WindowSize = ws_enc; /* see TS 44.060, table 12.5.2.1 */
|
|
pda_r99->LINK_QUALITY_MEASUREMENT_MODE = 0x0; /* no meas, see TS 44.060, table 11.2.7.2 */
|
|
pda_r99->Exist_BEP_PERIOD2 = 0; /* No extra EGPRS BEP PERIOD */
|
|
pda_r99->Exist_Packet_Extended_Timing_Advance = 0;
|
|
pda_r99->Exist_COMPACT_ReducedMA = 0;
|
|
}
|
|
|
|
/* generate paging request */
|
|
int Encoding::write_paging_request(bitvec * dest, uint8_t *ptmsi, uint16_t ptmsi_len)
|
|
{
|
|
unsigned wp = 0;
|
|
int plen;
|
|
|
|
bitvec_write_field(dest, wp,0x0,4); // Skip Indicator
|
|
bitvec_write_field(dest, wp,0x6,4); // Protocol Discriminator
|
|
bitvec_write_field(dest, wp,0x21,8); // Paging Request Message Type
|
|
|
|
bitvec_write_field(dest, wp,0x0,4); // Page Mode
|
|
bitvec_write_field(dest, wp,0x0,4); // Channel Needed
|
|
|
|
// Mobile Identity
|
|
bitvec_write_field(dest, wp,ptmsi_len+1,8); // Mobile Identity length
|
|
bitvec_write_field(dest, wp,0xf,4); // unused
|
|
bitvec_write_field(dest, wp,0x4,4); // PTMSI type
|
|
for (int i = 0; i < ptmsi_len; i++)
|
|
{
|
|
bitvec_write_field(dest, wp,ptmsi[i],8); // PTMSI
|
|
}
|
|
if ((wp % 8)) {
|
|
LOGP(DRLCMACUL, LOGL_ERROR, "Length of PAG.REQ without rest "
|
|
"octets is not multiple of 8 bits, PLEASE FIX!\n");
|
|
exit (0);
|
|
}
|
|
plen = wp / 8;
|
|
bitvec_write_field(dest, wp,0x0,1); // "L" NLN(PCH) = off
|
|
bitvec_write_field(dest, wp,0x0,1); // "L" Priority1 = off
|
|
bitvec_write_field(dest, wp,0x1,1); // "L" Priority2 = off
|
|
bitvec_write_field(dest, wp,0x0,1); // "L" Group Call information = off
|
|
bitvec_write_field(dest, wp,0x0,1); // "H" Packet Page Indication 1 = packet paging procedure
|
|
bitvec_write_field(dest, wp,0x1,1); // "H" Packet Page Indication 2 = packet paging procedure
|
|
|
|
return plen;
|
|
}
|
|
|
|
/**
|
|
* The index of the array show_rbb is the bit position inside the rbb
|
|
* (show_rbb[63] relates to BSN ssn-1)
|
|
*/
|
|
void Encoding::encode_rbb(const char *show_rbb, uint8_t *rbb)
|
|
{
|
|
uint8_t rbb_byte = 0;
|
|
|
|
// RECEIVE_BLOCK_BITMAP
|
|
for (int i = 0; i < 64; i++) {
|
|
/* Set bit at the appropriate position (see 3GPP TS 04.60 9.1.8.1) */
|
|
if (show_rbb[i] == 'R')
|
|
rbb_byte |= 1<< (7-(i%8));
|
|
|
|
if((i%8) == 7) {
|
|
rbb[i/8] = rbb_byte;
|
|
rbb_byte = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
static void write_packet_ack_nack_desc_gprs(
|
|
struct gprs_rlcmac_bts *bts, bitvec * dest, unsigned& wp,
|
|
gprs_rlc_ul_window *window, bool is_final)
|
|
{
|
|
char rbb[65];
|
|
|
|
window->update_rbb(rbb);
|
|
|
|
rbb[64] = 0;
|
|
LOGP(DRLCMACUL, LOGL_DEBUG, "- V(N): \"%s\" R=Received "
|
|
"I=Invalid\n", rbb);
|
|
|
|
bitvec_write_field(dest, wp, is_final, 1); // FINAL_ACK_INDICATION
|
|
bitvec_write_field(dest, wp, window->ssn(), 7); // STARTING_SEQUENCE_NUMBER
|
|
|
|
for (int i = 0; i < 64; i++) {
|
|
/* Set bit at the appropriate position (see 3GPP TS 04.60 9.1.8.1) */
|
|
bool is_ack = (rbb[i] == 'R');
|
|
bitvec_write_field(dest, wp, is_ack, 1);
|
|
}
|
|
}
|
|
|
|
static void write_packet_uplink_ack_gprs(
|
|
struct gprs_rlcmac_bts *bts, bitvec * dest, unsigned& wp,
|
|
struct gprs_rlcmac_ul_tbf *tbf, bool is_final)
|
|
{
|
|
|
|
bitvec_write_field(dest, wp, tbf->current_cs().to_num() - 1, 2); // CHANNEL_CODING_COMMAND
|
|
write_packet_ack_nack_desc_gprs(bts, dest, wp, &tbf->m_window, is_final);
|
|
|
|
bitvec_write_field(dest, wp, 1, 1); // 1: have CONTENTION_RESOLUTION_TLLI
|
|
bitvec_write_field(dest, wp, tbf->tlli(), 32); // CONTENTION_RESOLUTION_TLLI
|
|
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: don't have Packet Timing Advance
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: don't have Power Control Parameters
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: don't have Extension Bits
|
|
bitvec_write_field(dest, wp, 0, 1); // fixed 0
|
|
bitvec_write_field(dest, wp, 1, 1); // 1: have Additions R99
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: don't have Packet Extended Timing Advance
|
|
bitvec_write_field(dest, wp, 1, 1); // TBF_EST (enabled)
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: don't have REL 5
|
|
};
|
|
|
|
static void write_packet_ack_nack_desc_egprs(
|
|
struct gprs_rlcmac_bts *bts, bitvec * dest, unsigned& wp,
|
|
gprs_rlc_ul_window *window, bool is_final)
|
|
{
|
|
int urbb_len = 0;
|
|
int crbb_len = 0;
|
|
int len;
|
|
bool bow = true;
|
|
bool eow = true;
|
|
int ssn = window->mod_sns(window->v_q() + 1);
|
|
int num_blocks = window->mod_sns(window->v_r() - window->v_q());
|
|
int esn_crbb = window->mod_sns(ssn - 1);
|
|
int rest_bits = dest->data_len * 8 - wp;
|
|
|
|
if (num_blocks > 0)
|
|
/* V(Q) is NACK and omitted -> SSN = V(Q) + 1 */
|
|
num_blocks -= 1;
|
|
|
|
if (num_blocks > window->ws())
|
|
num_blocks = window->ws();
|
|
|
|
if (num_blocks > rest_bits) {
|
|
eow = false;
|
|
urbb_len = rest_bits;
|
|
/* TODO: use compression, start encoding bits and stop when the
|
|
* space is exhausted. Use the first combination that encodes
|
|
* all bits. If there is none, use the combination that encodes
|
|
* the largest number of bits (e.g. by setting num_blocks to the
|
|
* max and repeating the construction).
|
|
*/
|
|
} else if (num_blocks > rest_bits - 9) {
|
|
/* union bit and length field take 9 bits */
|
|
eow = false;
|
|
urbb_len = rest_bits - 9;
|
|
/* TODO: use compression (see above) */
|
|
}
|
|
|
|
if (urbb_len + crbb_len == rest_bits)
|
|
len = -1;
|
|
else if (crbb_len == 0)
|
|
len = urbb_len + 15;
|
|
else
|
|
len = urbb_len + crbb_len + 23;
|
|
|
|
/* EGPRS Ack/Nack Description IE */
|
|
if (len < 0) {
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: don't have length
|
|
} else {
|
|
bitvec_write_field(dest, wp, 1, 1); // 1: have length
|
|
bitvec_write_field(dest, wp, len, 8); // length
|
|
}
|
|
|
|
bitvec_write_field(dest, wp, is_final, 1); // FINAL_ACK_INDICATION
|
|
bitvec_write_field(dest, wp, bow, 1); // BEGINNING_OF_WINDOW
|
|
bitvec_write_field(dest, wp, eow, 1); // END_OF_WINDOW
|
|
bitvec_write_field(dest, wp, ssn, 11); // STARTING_SEQUENCE_NUMBER
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: don't have CRBB
|
|
|
|
/* TODO: Add CRBB support */
|
|
|
|
LOGP(DRLCMACUL, LOGL_DEBUG,
|
|
" - EGPRS URBB, len = %d, SSN = %d, ESN_CRBB = %d, "
|
|
"SNS = %d, WS = %d, V(Q) = %d, V(R) = %d%s%s\n",
|
|
urbb_len, ssn, esn_crbb,
|
|
window->sns(), window->ws(), window->v_q(), window->v_r(),
|
|
bow ? ", BOW" : "", eow ? ", EOW" : "");
|
|
for (int i = urbb_len; i > 0; i--) {
|
|
/* Set bit at the appropriate position (see 3GPP TS 04.60 12.3.1) */
|
|
bool is_ack = window->m_v_n.is_received(esn_crbb + i);
|
|
bitvec_write_field(dest, wp, is_ack, 1);
|
|
}
|
|
}
|
|
|
|
static void write_packet_uplink_ack_egprs(
|
|
struct gprs_rlcmac_bts *bts, bitvec * dest, unsigned& wp,
|
|
struct gprs_rlcmac_ul_tbf *tbf, bool is_final)
|
|
{
|
|
bitvec_write_field(dest, wp, 0, 2); // fixed 00
|
|
bitvec_write_field(dest, wp, 2, 4); // CHANNEL_CODING_COMMAND: MCS-3
|
|
// bitvec_write_field(dest, wp, tbf->current_cs() - 1, 4); // CHANNEL_CODING_COMMAND
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: no RESEGMENT (nyi)
|
|
bitvec_write_field(dest, wp, 1, 1); // PRE_EMPTIVE_TRANSMISSION, TODO: This resembles GPRS, change it?
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: no PRR_RETRANSMISSION_REQUEST, TODO: clarify
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: no ARAC_RETRANSMISSION_REQUEST, TODO: clarify
|
|
bitvec_write_field(dest, wp, 1, 1); // 1: have CONTENTION_RESOLUTION_TLLI
|
|
bitvec_write_field(dest, wp, tbf->tlli(), 32); // CONTENTION_RESOLUTION_TLLI
|
|
bitvec_write_field(dest, wp, 1, 1); // TBF_EST (enabled)
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: don't have Packet Timing Advance
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: don't have Packet Extended Timing Advance
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: don't have Power Control Parameters
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: don't have Extension Bits
|
|
|
|
write_packet_ack_nack_desc_egprs(bts, dest, wp, &tbf->m_window, is_final);
|
|
|
|
bitvec_write_field(dest, wp, 0, 1); // fixed 0
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: don't have REL 5
|
|
};
|
|
|
|
void Encoding::write_packet_uplink_ack(
|
|
struct gprs_rlcmac_bts *bts, bitvec * dest,
|
|
struct gprs_rlcmac_ul_tbf *tbf, bool is_final)
|
|
{
|
|
unsigned wp = 0;
|
|
|
|
LOGP(DRLCMACUL, LOGL_DEBUG, "Encoding Ack/Nack for %s "
|
|
"(final=%d)\n", tbf_name(tbf), is_final);
|
|
|
|
bitvec_write_field(dest, wp, 0x1, 2); // Payload Type
|
|
bitvec_write_field(dest, wp, 0x0, 2); // Uplink block with TDMA framenumber (N+13)
|
|
bitvec_write_field(dest, wp, is_final, 1); // Suppl/Polling Bit
|
|
bitvec_write_field(dest, wp, 0x0, 3); // Uplink state flag
|
|
bitvec_write_field(dest, wp, 0x9, 6); // MESSAGE TYPE Uplink Ack/Nack
|
|
bitvec_write_field(dest, wp, 0x0, 2); // Page Mode
|
|
|
|
bitvec_write_field(dest, wp, 0x0, 2); // fixed 00
|
|
bitvec_write_field(dest, wp, tbf->tfi(), 5); // Uplink TFI
|
|
|
|
if (tbf->is_egprs_enabled()) {
|
|
/* PU_AckNack_EGPRS = on */
|
|
bitvec_write_field(dest, wp, 1, 1); // 1: EGPRS
|
|
write_packet_uplink_ack_egprs(bts, dest, wp, tbf, is_final);
|
|
} else {
|
|
/* PU_AckNack_GPRS = on */
|
|
bitvec_write_field(dest, wp, 0, 1); // 0: GPRS
|
|
write_packet_uplink_ack_gprs(bts, dest, wp, tbf, is_final);
|
|
}
|
|
|
|
LOGP(DRLCMACUL, LOGL_DEBUG,
|
|
"Uplink Ack/Nack bit count %d, max %d, message = %s\n",
|
|
wp, dest->data_len * 8,
|
|
osmo_hexdump(dest->data, dest->data_len));
|
|
}
|
|
|
|
unsigned Encoding::write_packet_paging_request(bitvec * dest)
|
|
{
|
|
unsigned wp = 0;
|
|
|
|
bitvec_write_field(dest, wp,0x1,2); // Payload Type
|
|
bitvec_write_field(dest, wp,0x0,3); // No polling
|
|
bitvec_write_field(dest, wp,0x0,3); // Uplink state flag
|
|
bitvec_write_field(dest, wp,0x22,6); // MESSAGE TYPE
|
|
|
|
bitvec_write_field(dest, wp,0x0,2); // Page Mode
|
|
|
|
bitvec_write_field(dest, wp,0x0,1); // No PERSISTENCE_LEVEL
|
|
bitvec_write_field(dest, wp,0x0,1); // No NLN
|
|
|
|
return wp;
|
|
}
|
|
|
|
unsigned Encoding::write_repeated_page_info(bitvec * dest, unsigned& wp, uint8_t len,
|
|
uint8_t *identity, uint8_t chan_needed)
|
|
{
|
|
bitvec_write_field(dest, wp,0x1,1); // Repeated Page info exists
|
|
|
|
bitvec_write_field(dest, wp,0x1,1); // RR connection paging
|
|
|
|
if ((identity[0] & 0x07) == 4) {
|
|
bitvec_write_field(dest, wp,0x0,1); // TMSI
|
|
identity++;
|
|
len--;
|
|
} else {
|
|
bitvec_write_field(dest, wp,0x0,1); // MI
|
|
bitvec_write_field(dest, wp,len,4); // MI len
|
|
}
|
|
while (len) {
|
|
bitvec_write_field(dest, wp,*identity++,8); // MI data
|
|
len--;
|
|
}
|
|
bitvec_write_field(dest, wp,chan_needed,2); // CHANNEL_NEEDED
|
|
bitvec_write_field(dest, wp,0x0,1); // No eMLPP_PRIORITY
|
|
|
|
return wp;
|
|
}
|
|
|
|
int Encoding::rlc_write_dl_data_header(const struct gprs_rlc_data_info *rlc,
|
|
uint8_t *data)
|
|
{
|
|
struct gprs_rlc_dl_header_egprs_3 *egprs3;
|
|
struct rlc_dl_header *gprs;
|
|
unsigned int e_fbi_header;
|
|
GprsCodingScheme cs = rlc->cs;
|
|
|
|
switch(cs.headerTypeData()) {
|
|
case GprsCodingScheme::HEADER_GPRS_DATA:
|
|
gprs = static_cast<struct rlc_dl_header *>
|
|
((void *)data);
|
|
|
|
gprs->usf = rlc->usf;
|
|
gprs->s_p = rlc->es_p != 0 ? 1 : 0;
|
|
gprs->rrbp = rlc->rrbp;
|
|
gprs->pt = 0;
|
|
gprs->tfi = rlc->tfi;
|
|
gprs->pr = rlc->pr;
|
|
|
|
gprs->fbi = rlc->block_info[0].cv == 0;
|
|
gprs->e = rlc->block_info[0].e;
|
|
gprs->bsn = rlc->block_info[0].bsn;
|
|
break;
|
|
|
|
case GprsCodingScheme::HEADER_EGPRS_DATA_TYPE_3:
|
|
egprs3 = static_cast<struct gprs_rlc_dl_header_egprs_3 *>
|
|
((void *)data);
|
|
|
|
egprs3->usf = rlc->usf;
|
|
egprs3->es_p = rlc->es_p;
|
|
egprs3->rrbp = rlc->rrbp;
|
|
egprs3->tfi_a = rlc->tfi >> 0; /* 1 bit LSB */
|
|
egprs3->tfi_b = rlc->tfi >> 1; /* 4 bits */
|
|
egprs3->pr = rlc->pr;
|
|
egprs3->cps = rlc->cps;
|
|
|
|
egprs3->bsn1_a = rlc->block_info[0].bsn >> 0; /* 2 bits LSB */
|
|
egprs3->bsn1_b = rlc->block_info[0].bsn >> 2; /* 8 bits */
|
|
egprs3->bsn1_c = rlc->block_info[0].bsn >> 10; /* 1 bit */
|
|
|
|
egprs3->spb = rlc->block_info[0].spb;
|
|
|
|
e_fbi_header = rlc->block_info[0].e ? 0x01 : 0;
|
|
e_fbi_header |= rlc->block_info[0].cv == 0 ? 0x02 : 0; /* FBI */
|
|
e_fbi_header <<= 7;
|
|
data[3] = (data[3] & 0b01111111) | (e_fbi_header >> 0);
|
|
data[4] = (data[4] & 0b11111110) | (e_fbi_header >> 8);
|
|
break;
|
|
|
|
case GprsCodingScheme::HEADER_EGPRS_DATA_TYPE_1:
|
|
case GprsCodingScheme::HEADER_EGPRS_DATA_TYPE_2:
|
|
/* TODO: Support both header types */
|
|
/* fall through */
|
|
default:
|
|
LOGP(DRLCMACDL, LOGL_ERROR,
|
|
"Encoding of uplink %s data blocks not yet supported.\n",
|
|
cs.name());
|
|
return -ENOTSUP;
|
|
};
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* \brief Copy LSB bitstream RLC data block from byte aligned buffer.
|
|
*
|
|
* Note that the bitstream is encoded in LSB first order, so the two octets
|
|
* 654321xx xxxxxx87 contain the octet 87654321 starting at bit position 3
|
|
* (LSB has bit position 1). This is a different order than the one used by
|
|
* CSN.1.
|
|
*
|
|
* \param data_block_idx The block index, 0..1 for header type 1, 0 otherwise
|
|
* \param src A pointer to the start of the RLC block (incl. the header)
|
|
* \param buffer A data area of a least the size of the RLC block
|
|
* \returns the number of bytes copied
|
|
*/
|
|
unsigned int Encoding::rlc_copy_from_aligned_buffer(
|
|
const struct gprs_rlc_data_info *rlc,
|
|
unsigned int data_block_idx,
|
|
uint8_t *dst, const uint8_t *buffer)
|
|
{
|
|
unsigned int hdr_bytes;
|
|
unsigned int extra_bits;
|
|
unsigned int i;
|
|
|
|
uint8_t c, last_c;
|
|
const uint8_t *src;
|
|
const struct gprs_rlc_data_block_info *rdbi;
|
|
|
|
OSMO_ASSERT(data_block_idx < rlc->num_data_blocks);
|
|
rdbi = &rlc->block_info[data_block_idx];
|
|
|
|
hdr_bytes = rlc->data_offs_bits[data_block_idx] / 8;
|
|
extra_bits = (rlc->data_offs_bits[data_block_idx] % 8);
|
|
|
|
if (extra_bits == 0) {
|
|
/* It is aligned already */
|
|
memmove(dst + hdr_bytes, buffer, rdbi->data_len);
|
|
return rdbi->data_len;
|
|
}
|
|
|
|
src = buffer;
|
|
dst = dst + hdr_bytes;
|
|
last_c = *dst << (8 - extra_bits);
|
|
|
|
for (i = 0; i < rdbi->data_len; i++) {
|
|
c = src[i];
|
|
*(dst++) = (last_c >> (8 - extra_bits)) | (c << extra_bits);
|
|
last_c = c;
|
|
}
|
|
|
|
/* overwrite the lower extra_bits */
|
|
*dst = (*dst & (0xff << extra_bits)) | (last_c >> (8 - extra_bits));
|
|
|
|
return rdbi->data_len;
|
|
}
|
|
|
|
static Encoding::AppendResult rlc_data_to_dl_append_gprs(
|
|
struct gprs_rlc_data_block_info *rdbi,
|
|
gprs_llc *llc, int *offset, int *num_chunks,
|
|
uint8_t *data_block,
|
|
bool is_final)
|
|
{
|
|
int chunk;
|
|
int space;
|
|
struct rlc_li_field *li;
|
|
uint8_t *delimiter, *data, *e_pointer;
|
|
|
|
data = data_block + *offset;
|
|
delimiter = data_block + *num_chunks;
|
|
e_pointer = (*num_chunks ? delimiter - 1 : NULL);
|
|
|
|
chunk = llc->chunk_size();
|
|
space = rdbi->data_len - *offset;
|
|
|
|
/* if chunk will exceed block limit */
|
|
if (chunk > space) {
|
|
LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d "
|
|
"larger than space (%d) left in block: copy "
|
|
"only remaining space, and we are done\n",
|
|
chunk, space);
|
|
/* block is filled, so there is no extension */
|
|
if (e_pointer)
|
|
*e_pointer |= 0x01;
|
|
/* fill only space */
|
|
llc->consume(data, space);
|
|
/* return data block as message */
|
|
*offset = rdbi->data_len;
|
|
(*num_chunks)++;
|
|
return Encoding::AR_NEED_MORE_BLOCKS;
|
|
}
|
|
/* if FINAL chunk would fit precisely in space left */
|
|
if (chunk == space && is_final)
|
|
{
|
|
LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d "
|
|
"would exactly fit into space (%d): because "
|
|
"this is a final block, we don't add length "
|
|
"header, and we are done\n", chunk, space);
|
|
/* block is filled, so there is no extension */
|
|
if (e_pointer)
|
|
*e_pointer |= 0x01;
|
|
/* fill space */
|
|
llc->consume(data, space);
|
|
*offset = rdbi->data_len;
|
|
(*num_chunks)++;
|
|
rdbi->cv = 0;
|
|
return Encoding::AR_COMPLETED_BLOCK_FILLED;
|
|
}
|
|
/* if chunk would fit exactly in space left */
|
|
if (chunk == space) {
|
|
LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d "
|
|
"would exactly fit into space (%d): add length "
|
|
"header with LI=0, to make frame extend to "
|
|
"next block, and we are done\n", chunk, space);
|
|
/* make space for delimiter */
|
|
if (delimiter != data)
|
|
memmove(delimiter + 1, delimiter,
|
|
data - delimiter);
|
|
data++;
|
|
(*offset)++;
|
|
space--;
|
|
/* add LI with 0 length */
|
|
li = (struct rlc_li_field *)delimiter;
|
|
li->e = 1; /* not more extension */
|
|
li->m = 0; /* shall be set to 0, in case of li = 0 */
|
|
li->li = 0; /* chunk fills the complete space */
|
|
rdbi->e = 0; /* 0: extensions present */
|
|
// no need to set e_pointer nor increase delimiter
|
|
/* fill only space, which is 1 octet less than chunk */
|
|
llc->consume(data, space);
|
|
/* return data block as message */
|
|
*offset = rdbi->data_len;
|
|
(*num_chunks)++;
|
|
return Encoding::AR_NEED_MORE_BLOCKS;
|
|
}
|
|
|
|
LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d is less "
|
|
"than remaining space (%d): add length header to "
|
|
"to delimit LLC frame\n", chunk, space);
|
|
/* the LLC frame chunk ends in this block */
|
|
/* make space for delimiter */
|
|
if (delimiter != data)
|
|
memmove(delimiter + 1, delimiter, data - delimiter);
|
|
data++;
|
|
(*offset)++;
|
|
space--;
|
|
/* add LI to delimit frame */
|
|
li = (struct rlc_li_field *)delimiter;
|
|
li->e = 0; /* Extension bit, maybe set later */
|
|
li->m = 0; /* will be set later, if there is more LLC data */
|
|
li->li = chunk; /* length of chunk */
|
|
rdbi->e = 0; /* 0: extensions present */
|
|
(*num_chunks)++;
|
|
/* copy (rest of) LLC frame to space and reset later */
|
|
llc->consume(data, chunk);
|
|
data += chunk;
|
|
space -= chunk;
|
|
(*offset) += chunk;
|
|
/* if we have more data and we have space left */
|
|
if (space > 0 && !is_final) {
|
|
li->m = 1; /* we indicate more frames to follow */
|
|
return Encoding::AR_COMPLETED_SPACE_LEFT;
|
|
}
|
|
/* if we don't have more LLC frames */
|
|
if (is_final) {
|
|
LOGP(DRLCMACDL, LOGL_DEBUG, "-- Final block, so we "
|
|
"done.\n");
|
|
li->e = 1; /* we cannot extend */
|
|
rdbi->cv = 0;
|
|
return Encoding::AR_COMPLETED_BLOCK_FILLED;
|
|
}
|
|
/* we have no space left */
|
|
LOGP(DRLCMACDL, LOGL_DEBUG, "-- No space left, so we are "
|
|
"done.\n");
|
|
li->e = 1; /* we cannot extend */
|
|
return Encoding::AR_COMPLETED_BLOCK_FILLED;
|
|
}
|
|
|
|
static Encoding::AppendResult rlc_data_to_dl_append_egprs(
|
|
struct gprs_rlc_data_block_info *rdbi,
|
|
gprs_llc *llc, int *offset, int *num_chunks,
|
|
uint8_t *data_block,
|
|
bool is_final)
|
|
{
|
|
int chunk;
|
|
int space;
|
|
struct rlc_li_field_egprs *li;
|
|
struct rlc_li_field_egprs *prev_li;
|
|
uint8_t *delimiter, *data;
|
|
|
|
data = data_block + *offset;
|
|
delimiter = data_block + *num_chunks;
|
|
prev_li = (struct rlc_li_field_egprs *)
|
|
(*num_chunks ? delimiter - 1 : NULL);
|
|
|
|
chunk = llc->chunk_size();
|
|
space = rdbi->data_len - *offset;
|
|
|
|
/* if chunk will exceed block limit */
|
|
if (chunk > space) {
|
|
LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d "
|
|
"larger than space (%d) left in block: copy "
|
|
"only remaining space, and we are done\n",
|
|
chunk, space);
|
|
/* fill only space */
|
|
llc->consume(data, space);
|
|
/* return data block as message */
|
|
*offset = rdbi->data_len;
|
|
(*num_chunks)++;
|
|
return Encoding::AR_NEED_MORE_BLOCKS;
|
|
}
|
|
/* if FINAL chunk would fit precisely in space left */
|
|
if (chunk == space && is_final)
|
|
{
|
|
LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d "
|
|
"would exactly fit into space (%d): because "
|
|
"this is a final block, we don't add length "
|
|
"header, and we are done\n", chunk, space);
|
|
/* fill space */
|
|
llc->consume(data, space);
|
|
*offset = rdbi->data_len;
|
|
(*num_chunks)++;
|
|
rdbi->cv = 0;
|
|
return Encoding::AR_COMPLETED_BLOCK_FILLED;
|
|
}
|
|
/* if chunk would fit exactly in space left */
|
|
if (chunk == space) {
|
|
LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d "
|
|
"would exactly fit into space (%d): just copy "
|
|
"it, and we are done. The next block will have "
|
|
"to start with an empty chunk\n",
|
|
chunk, space);
|
|
/* fill space */
|
|
llc->consume(data, space);
|
|
*offset = rdbi->data_len;
|
|
(*num_chunks)++;
|
|
return Encoding::AR_NEED_MORE_BLOCKS;
|
|
}
|
|
|
|
LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d is less "
|
|
"than remaining space (%d): add length header to "
|
|
"to delimit LLC frame\n", chunk, space);
|
|
/* the LLC frame chunk ends in this block */
|
|
/* make space for delimiter */
|
|
|
|
if (delimiter != data)
|
|
memmove(delimiter + 1, delimiter, data - delimiter);
|
|
|
|
data += 1;
|
|
(*offset) += 1;
|
|
space -= 1;
|
|
/* add LI to delimit frame */
|
|
li = (struct rlc_li_field_egprs *)delimiter;
|
|
li->e = 1; /* Extension bit, maybe set later */
|
|
li->li = chunk; /* length of chunk */
|
|
/* tell previous extension header about the new one */
|
|
if (prev_li)
|
|
prev_li->e = 0;
|
|
rdbi->e = 0; /* 0: extensions present */
|
|
delimiter++;
|
|
prev_li = li;
|
|
(*num_chunks)++;
|
|
/* copy (rest of) LLC frame to space and reset later */
|
|
llc->consume(data, chunk);
|
|
data += chunk;
|
|
space -= chunk;
|
|
(*offset) += chunk;
|
|
/* if we have more data and we have space left */
|
|
if (space > 0) {
|
|
if (!is_final)
|
|
return Encoding::AR_COMPLETED_SPACE_LEFT;
|
|
|
|
/* we don't have more LLC frames */
|
|
/* We will have to add another chunk with filling octets */
|
|
LOGP(DRLCMACDL, LOGL_DEBUG,
|
|
"-- There is remaining space (%d): add filling byte chunk\n",
|
|
space);
|
|
|
|
if (delimiter != data)
|
|
memmove(delimiter + 1, delimiter, data - delimiter);
|
|
|
|
data += 1;
|
|
(*offset) += 1;
|
|
space -= 1;
|
|
|
|
/* set filling bytes extension */
|
|
li = (struct rlc_li_field_egprs *)delimiter;
|
|
li->e = 1;
|
|
li->li = 127;
|
|
|
|
/* tell previous extension header about the new one */
|
|
if (prev_li)
|
|
prev_li->e = 0;
|
|
|
|
delimiter++;
|
|
(*num_chunks)++;
|
|
|
|
rdbi->cv = 0;
|
|
|
|
LOGP(DRLCMACDL, LOGL_DEBUG, "-- Final block, so we "
|
|
"are done.\n");
|
|
|
|
*offset = rdbi->data_len;
|
|
return Encoding::AR_COMPLETED_BLOCK_FILLED;
|
|
}
|
|
|
|
if (is_final) {
|
|
/* we don't have more LLC frames */
|
|
LOGP(DRLCMACDL, LOGL_DEBUG, "-- Final block, so we "
|
|
"are done.\n");
|
|
rdbi->cv = 0;
|
|
return Encoding::AR_COMPLETED_BLOCK_FILLED;
|
|
}
|
|
|
|
/* we have no space left */
|
|
LOGP(DRLCMACDL, LOGL_DEBUG, "-- No space left, so we are "
|
|
"done.\n");
|
|
return Encoding::AR_COMPLETED_BLOCK_FILLED;
|
|
}
|
|
|
|
Encoding::AppendResult Encoding::rlc_data_to_dl_append(
|
|
struct gprs_rlc_data_block_info *rdbi, GprsCodingScheme cs,
|
|
gprs_llc *llc, int *offset, int *num_chunks,
|
|
uint8_t *data_block,
|
|
bool is_final)
|
|
{
|
|
if (cs.isGprs())
|
|
return rlc_data_to_dl_append_gprs(rdbi,
|
|
llc, offset, num_chunks, data_block, is_final);
|
|
|
|
if (cs.isEgprs())
|
|
return rlc_data_to_dl_append_egprs(rdbi,
|
|
llc, offset, num_chunks, data_block, is_final);
|
|
|
|
LOGP(DRLCMACDL, LOGL_ERROR, "%s data block encoding not implemented\n",
|
|
cs.name());
|
|
|
|
return AR_NEED_MORE_BLOCKS;
|
|
}
|