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edge: Support EGPRS uplink Ack/Nack messages 

This commit adds EGPRS UL Ack/Nack encoding based on the CSN1 code.

Note that the bitmap encoding is still broken and not easy to fix
with the CSN1 framework, especially w.r.t. the length field.
Therefore this implementation will be abandoned and replaced by a
bitvec based one.

Sponsored-by: On-Waves ehf
This commit is contained in:
Jacob Erlbeck 2015-12-21 17:23:16 +01:00
parent 2e3a81e4b3
commit 2b3121eebf
1 changed files with 61 additions and 4 deletions
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65
src/encoding.cpp
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@ -431,6 +431,54 @@ static void write_packet_uplink_ack_gprs(struct gprs_rlcmac_bts *bts,
acknack_data->Exist_Power_Control_Parameters = 0x0;
}
static void write_packet_uplink_ack_egprs(struct gprs_rlcmac_bts *bts,
PU_AckNack_EGPRS_00_t *acknack, struct gprs_rlcmac_ul_tbf *tbf,
int is_final)
{
Common_Uplink_Ack_Nack_Data_t *acknack_data =
&acknack->Common_Uplink_Ack_Nack_Data;
char rbb[65];
int bow = 1;
int eow = 1;
int ssn = (tbf->m_window.v_q() + 1) & tbf->m_window.mod_sns();
tbf->m_window.update_rbb(rbb);
/* rbb is not NULL terminated */
rbb[64] = 0;
LOGP(DRLCMACUL, LOGL_DEBUG, "- V(N): \"%s\" R=Received "
"I=Invalid\n", rbb);
/* TODO: Use tbf->current_cs() when it supports EGPRS */
acknack->EGPRS_ChannelCodingCommand = 2; /* MCS-3 */
acknack->RESEGMENT = 0; /* NYI */
acknack->PRE_EMPTIVE_TRANSMISSION = 1; /* TODO: This resembles GPRS, change it? */
acknack->PRR_RETRANSMISSION_REQUEST = 0; /* TODO: Needs clarification */
acknack->ARAC_RETRANSMISSION_REQUEST = 0; /* TODO: Needs clarification */
acknack_data->Exist_CONTENTION_RESOLUTION_TLLI = 0x1;
acknack_data->CONTENTION_RESOLUTION_TLLI = tbf->tlli();
acknack->TBF_EST = 1; /* Enable RR on PACCH */
acknack_data->Exist_Packet_Timing_Advance = 0x0;
acknack->Exist_Packet_Extended_Timing_Advance = 0x0;
acknack_data->Exist_Power_Control_Parameters = 0x0;
acknack_data->Exist_Extension_Bits = 0x0;
acknack->EGPRS_AckNack.UnionType = 0;
acknack->EGPRS_AckNack.Desc.FINAL_ACK_INDICATION = is_final;
acknack->EGPRS_AckNack.Desc.BEGINNING_OF_WINDOW = eow;
acknack->EGPRS_AckNack.Desc.END_OF_WINDOW = bow;
acknack->EGPRS_AckNack.Desc.STARTING_SEQUENCE_NUMBER = ssn;
acknack->EGPRS_AckNack.Desc.Exist_CRBB = 0; /* TODO: Implement compressed bitmaps */
acknack->EGPRS_AckNack.Desc.URBB_LENGTH = 64;
Encoding::encode_rbb(rbb, acknack->EGPRS_AckNack.Desc.URBB);
}
/* generate uplink ack */
void Encoding::write_packet_uplink_ack(struct gprs_rlcmac_bts *bts,
RlcMacDownlink_t * block, struct gprs_rlcmac_ul_tbf *tbf,
@ -453,10 +501,19 @@ void Encoding::write_packet_uplink_ack(struct gprs_rlcmac_bts *bts,
acknack->PAGE_MODE = 0x0; // Normal Paging
acknack->UPLINK_TFI = tbf->tfi(); // Uplink TFI
/* PU_AckNack_GPRS = on */
acknack->UnionType = 0x0;
write_packet_uplink_ack_gprs(bts,
&acknack->u.PU_AckNack_GPRS_Struct, tbf, final);
if (tbf->is_egprs_enabled()) {
/* PU_AckNack_EGPRS = on */
acknack->UnionType = 0x1;
acknack->u.PU_AckNack_EGPRS_Struct.UnionType = 0x0;
write_packet_uplink_ack_egprs(bts,
&acknack->u.PU_AckNack_EGPRS_Struct.u.PU_AckNack_EGPRS_00,
tbf, final);
} else {
/* PU_AckNack_GPRS = on */
acknack->UnionType = 0x0;
write_packet_uplink_ack_gprs(bts,
&acknack->u.PU_AckNack_GPRS_Struct, tbf, final);
}
}
unsigned Encoding::write_packet_paging_request(bitvec * dest)