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osmo-trx/Transceiver52M/Transceiver.cpp
Vadim Yanitskiy c7fc94dff6 Transceiver::ctrl_sock_handle_rx(): fix copy-pasted comments 
Change-Id: If31c0de0b3562c06220dcb9ad6f0c13d8621f6e3
2024-01-23 04:12:20 +07:00

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/*
* Copyright 2008, 2009, 2010 Free Software Foundation, Inc.
*
* SPDX-License-Identifier: GPL-3.0+
*
* This software is distributed under the terms of the GNU Public License.
* See the COPYING file in the main directory for details.
*
* This use of this software may be subject to additional restrictions.
* See the LEGAL file in the main directory for details.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU 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 General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <netinet/in.h>
#include <iomanip> // std::setprecision
#include <fstream>
#include "Transceiver.h"
#include <Logger.h>
#include <grgsm_vitac/grgsm_vitac.h>
extern "C" {
#include "osmo_signal.h"
#include "proto_trxd.h"
#include <osmocom/core/utils.h>
#include <osmocom/core/socket.h>
#include <osmocom/core/bits.h>
#include <osmocom/vty/cpu_sched_vty.h>
}
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
using namespace GSM;
Transceiver *transceiver;
#define USB_LATENCY_INTRVL 10,0
/* Number of running values use in noise average */
#define NOISE_CNT 20
static void dispatch_trx_rate_ctr_change(TransceiverState *state, unsigned int chan) {
thread_enable_cancel(false);
state->ctrs.chan = chan;
osmo_signal_dispatch(SS_DEVICE, S_TRX_COUNTER_CHANGE, &state->ctrs);
thread_enable_cancel(true);
}
TransceiverState::TransceiverState()
: mFiller(FILLER_ZERO), mRetrans(false), mNoiseLev(0.0), mNoises(NOISE_CNT),
mPower(0.0), mMuted(false), first_dl_fn_rcv()
{
for (int i = 0; i < 8; i++) {
chanType[i] = Transceiver::NONE;
fillerModulus[i] = 26;
chanResponse[i] = NULL;
DFEForward[i] = NULL;
DFEFeedback[i] = NULL;
for (int n = 0; n < 102; n++)
fillerTable[n][i] = NULL;
}
memset(&ctrs, 0, sizeof(struct trx_counters));
}
TransceiverState::~TransceiverState()
{
for (int i = 0; i < 8; i++) {
delete chanResponse[i];
delete DFEForward[i];
delete DFEFeedback[i];
for (int n = 0; n < 102; n++)
delete fillerTable[n][i];
}
}
bool TransceiverState::init(FillerType filler, size_t sps, float scale, size_t rtsc, unsigned rach_delay)
{
signalVector *burst;
if ((sps != 1) && (sps != 4))
return false;
mFiller = filler;
for (size_t n = 0; n < 8; n++) {
for (size_t i = 0; i < 102; i++) {
switch (filler) {
case FILLER_DUMMY:
burst = generateDummyBurst(sps, n);
break;
case FILLER_NORM_RAND:
burst = genRandNormalBurst(rtsc, sps, n);
break;
case FILLER_EDGE_RAND:
burst = generateEdgeBurst(rtsc);
break;
case FILLER_ACCESS_RAND:
burst = genRandAccessBurst(rach_delay, sps, n);
break;
case FILLER_ZERO:
default:
burst = generateEmptyBurst(sps, n);
}
scaleVector(*burst, scale);
fillerTable[i][n] = burst;
}
if ((filler == FILLER_NORM_RAND) ||
(filler == FILLER_EDGE_RAND)) {
chanType[n] = TSC;
}
}
return false;
}
Transceiver::Transceiver(const struct trx_cfg *cfg,
GSM::Time wTransmitLatency,
RadioInterface *wRadioInterface)
: mChans(cfg->num_chans), cfg(cfg),
mCtrlSockets(mChans), mClockSocket(-1),
mTxPriorityQueues(mChans), mReceiveFIFO(mChans),
mRxServiceLoopThreads(mChans), mRxLowerLoopThread(nullptr), mTxLowerLoopThread(nullptr),
mTxPriorityQueueServiceLoopThreads(mChans), mTransmitLatency(wTransmitLatency), mRadioInterface(wRadioInterface),
mOn(false),mForceClockInterface(false), mTxFreq(0.0), mRxFreq(0.0), mTSC(0), mMaxExpectedDelayAB(0),
mMaxExpectedDelayNB(0), mWriteBurstToDiskMask(0), mVersionTRXD(mChans), mStates(mChans)
{
txFullScale = mRadioInterface->fullScaleInputValue();
rxFullScale = mRadioInterface->fullScaleOutputValue();
for (size_t i = 0; i < ARRAY_SIZE(mHandover); i++) {
for (size_t j = 0; j < ARRAY_SIZE(mHandover[i]); j++)
mHandover[i][j] = false;
}
}
Transceiver::~Transceiver()
{
stop();
sigProcLibDestroy();
if (mClockSocket >= 0)
close(mClockSocket);
for (size_t i = 0; i < mChans; i++) {
mTxPriorityQueues[i].clear();
if (mDataSockets[i] >= 0)
close(mDataSockets[i]);
}
}
int Transceiver::ctrl_sock_cb(struct osmo_fd *bfd, unsigned int flags)
{
int rc = 0;
int chan = static_cast<int>(reinterpret_cast<uintptr_t>(bfd->data));
if (flags & OSMO_FD_READ)
rc = transceiver->ctrl_sock_handle_rx(chan);
if (rc < 0)
osmo_signal_dispatch(SS_MAIN, S_MAIN_STOP_REQUIRED, NULL);
if (flags & OSMO_FD_WRITE)
rc = transceiver->ctrl_sock_write(chan);
if (rc < 0)
osmo_signal_dispatch(SS_MAIN, S_MAIN_STOP_REQUIRED, NULL);
return rc;
}
/*
* Initialize transceiver
*
* Start or restart the control loop. Any further control is handled through the
* socket API. Randomize the central radio clock set the downlink burst
* counters. Note that the clock will not update until the radio starts, but we
* are still expected to report clock indications through control channel
* activity.
*/
bool Transceiver::init()
{
int d_srcport, d_dstport, c_srcport, c_dstport;
if (!mChans) {
LOG(FATAL) << "No channels assigned";
return false;
}
if (!sigProcLibSetup()) {
LOG(FATAL) << "Failed to initialize signal processing library";
return false;
}
initvita();
mDataSockets.resize(mChans, -1);
/* Filler table retransmissions - support only on channel 0 */
if (cfg->filler == FILLER_DUMMY)
mStates[0].mRetrans = true;
/* Setup sockets */
mClockSocket = osmo_sock_init2(AF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP,
cfg->bind_addr, cfg->base_port,
cfg->remote_addr, cfg->base_port + 100,
OSMO_SOCK_F_BIND | OSMO_SOCK_F_CONNECT);
if (mClockSocket < 0)
return false;
for (size_t i = 0; i < mChans; i++) {
int rv;
FillerType filler = cfg->filler;
c_srcport = cfg->base_port + 2 * i + 1;
c_dstport = cfg->base_port + 2 * i + 101;
d_srcport = cfg->base_port + 2 * i + 2;
d_dstport = cfg->base_port + 2 * i + 102;
rv = osmo_sock_init2_ofd(&mCtrlSockets[i].conn_bfd, AF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP,
cfg->bind_addr, c_srcport,
cfg->remote_addr, c_dstport,
OSMO_SOCK_F_BIND | OSMO_SOCK_F_CONNECT);
if (rv < 0)
return false;
mCtrlSockets[i].conn_bfd.cb = ctrl_sock_cb;
mCtrlSockets[i].conn_bfd.data = reinterpret_cast<void*>(i);
mDataSockets[i] = osmo_sock_init2(AF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP,
cfg->bind_addr, d_srcport,
cfg->remote_addr, d_dstport,
OSMO_SOCK_F_BIND | OSMO_SOCK_F_CONNECT);
if (mDataSockets[i] < 0)
return false;
if (i && filler == FILLER_DUMMY)
filler = FILLER_ZERO;
mStates[i].init(filler, cfg->tx_sps, txFullScale, cfg->rtsc, cfg->rach_delay);
}
/* Randomize the central clock */
GSM::Time startTime(random() % gHyperframe, 0);
mRadioInterface->getClock()->set(startTime);
mTransmitDeadlineClock = startTime;
mLastClockUpdateTime = startTime;
mLatencyUpdateTime = startTime;
return true;
}
/*
* Start the transceiver
*
* Submit command(s) to the radio device to commence streaming samples and
* launch threads to handle sample I/O. Re-synchronize the transmit burst
* counters to the central radio clock here as well.
*/
bool Transceiver::start()
{
ScopedLock lock(mLock);
if (mOn) {
LOG(ERR) << "Transceiver already running";
return true;
}
LOG(NOTICE) << "Starting the transceiver";
GSM::Time time = mRadioInterface->getClock()->get();
mTransmitDeadlineClock = time;
mLastClockUpdateTime = time;
mLatencyUpdateTime = time;
if (!mRadioInterface->start()) {
LOG(FATAL) << "Device failed to start";
return false;
}
/* Device is running - launch I/O threads */
mRxLowerLoopThread = new Thread(cfg->stack_size);
mTxLowerLoopThread = new Thread(cfg->stack_size);
mTxLowerLoopThread->start((void * (*)(void*))
TxLowerLoopAdapter,(void*) this);
mRxLowerLoopThread->start((void * (*)(void*))
RxLowerLoopAdapter,(void*) this);
/* Launch uplink and downlink burst processing threads */
for (size_t i = 0; i < mChans; i++) {
TrxChanThParams *params = (TrxChanThParams *)malloc(sizeof(struct TrxChanThParams));
params->trx = this;
params->num = i;
mRxServiceLoopThreads[i] = new Thread(cfg->stack_size);
mRxServiceLoopThreads[i]->start((void * (*)(void*))
RxUpperLoopAdapter, (void*) params);
params = (TrxChanThParams *)malloc(sizeof(struct TrxChanThParams));
params->trx = this;
params->num = i;
mTxPriorityQueueServiceLoopThreads[i] = new Thread(cfg->stack_size);
mTxPriorityQueueServiceLoopThreads[i]->start((void * (*)(void*))
TxUpperLoopAdapter, (void*) params);
}
mForceClockInterface = true;
mOn = true;
return true;
}
/*
* Stop the transceiver
*
* Perform stopping by disabling receive streaming and issuing cancellation
* requests to running threads. Most threads will timeout and terminate once
* device is disabled, but the transmit loop may block waiting on the central
* UMTS clock. Explicitly signal the clock to make sure that the transmit loop
* makes it to the thread cancellation point.
*/
void Transceiver::stop()
{
ScopedLock lock(mLock);
if (!mOn)
return;
LOG(NOTICE) << "Stopping the transceiver";
mTxLowerLoopThread->cancel();
mRxLowerLoopThread->cancel();
mTxLowerLoopThread->join();
mRxLowerLoopThread->join();
delete mTxLowerLoopThread;
delete mRxLowerLoopThread;
for (size_t i = 0; i < mChans; i++) {
mRxServiceLoopThreads[i]->cancel();
mTxPriorityQueueServiceLoopThreads[i]->cancel();
}
LOG(INFO) << "Stopping the device";
mRadioInterface->stop();
for (size_t i = 0; i < mChans; i++) {
mRxServiceLoopThreads[i]->join();
mTxPriorityQueueServiceLoopThreads[i]->join();
delete mRxServiceLoopThreads[i];
delete mTxPriorityQueueServiceLoopThreads[i];
mTxPriorityQueues[i].clear();
}
mOn = false;
LOG(NOTICE) << "Transceiver stopped";
}
void Transceiver::addRadioVector(size_t chan, BitVector &bits,
int RSSI, GSM::Time &wTime)
{
signalVector *burst;
radioVector *radio_burst;
if (chan >= mTxPriorityQueues.size()) {
LOGCHAN(chan, DTRXDDL, FATAL) << "Invalid channel";
return;
}
if (wTime.TN() > 7) {
LOGCHAN(chan, DTRXDDL, FATAL) << "Received burst with invalid slot " << wTime.TN();
return;
}
/* Use the number of bits as the EDGE burst indicator */
if (bits.size() == EDGE_BURST_NBITS)
burst = modulateEdgeBurst(bits, cfg->tx_sps);
else
burst = modulateBurst(bits, 8 + (wTime.TN() % 4 == 0), cfg->tx_sps);
scaleVector(*burst, txFullScale * pow(10, (double) -RSSI / 20));
radio_burst = new radioVector(wTime, burst);
mTxPriorityQueues[chan].write(radio_burst);
}
void Transceiver::updateFillerTable(size_t chan, radioVector *burst)
{
int TN, modFN;
TransceiverState *state = &mStates[chan];
TN = burst->getTime().TN();
modFN = burst->getTime().FN() % state->fillerModulus[TN];
delete state->fillerTable[modFN][TN];
state->fillerTable[modFN][TN] = burst->getVector();
burst->setVector(NULL);
}
void Transceiver::pushRadioVector(GSM::Time &nowTime)
{
int TN, modFN;
radioVector *burst;
TransceiverState *state;
std::vector<signalVector *> bursts(mChans);
std::vector<bool> zeros(mChans);
std::vector<bool> filler(mChans, true);
bool ratectr_changed;
TN = nowTime.TN();
for (size_t i = 0; i < mChans; i ++) {
state = &mStates[i];
ratectr_changed = false;
zeros[i] = state->chanType[TN] == NONE || state->mMuted;
Mutex *mtx = mTxPriorityQueues[i].getMutex();
mtx->lock();
while ((burst = mTxPriorityQueues[i].getStaleBurst(nowTime))) {
LOGCHAN(i, DTRXDDL, INFO) << "dumping STALE burst in TRX->SDR interface ("
<< burst->getTime() <<" vs " << nowTime << "), retrans=" << state->mRetrans;
state->ctrs.tx_stale_bursts++;
ratectr_changed = true;
if (state->mRetrans)
updateFillerTable(i, burst);
delete burst;
}
if ((burst = mTxPriorityQueues[i].getCurrentBurst(nowTime))) {
bursts[i] = burst->getVector();
if (state->mRetrans) {
updateFillerTable(i, burst);
} else {
burst->setVector(NULL);
filler[i] = false;
}
delete burst;
} else {
modFN = nowTime.FN() % state->fillerModulus[TN];
bursts[i] = state->fillerTable[modFN][TN];
if (i == 0 && state->mFiller == FILLER_ZERO) {
LOGCHAN(i, DTRXDDL, INFO) << "No Tx burst available for " << nowTime
<< ", retrans=" << state->mRetrans;
state->ctrs.tx_unavailable_bursts++;
ratectr_changed = true;
}
}
mtx->unlock();
if (ratectr_changed)
dispatch_trx_rate_ctr_change(state, i);
}
mRadioInterface->driveTransmitRadio(bursts, zeros);
for (size_t i = 0; i < mChans; i++) {
if (!filler[i])
delete bursts[i];
}
}
void Transceiver::setModulus(size_t timeslot, size_t chan)
{
TransceiverState *state = &mStates[chan];
switch (state->chanType[timeslot]) {
case NONE:
case I:
case II:
case III:
case FILL:
state->fillerModulus[timeslot] = 26;
break;
case IV:
case VI:
case V:
state->fillerModulus[timeslot] = 51;
break;
//case V:
case VII:
state->fillerModulus[timeslot] = 102;
break;
case XIII:
state->fillerModulus[timeslot] = 52;
break;
default:
break;
}
}
CorrType Transceiver::expectedCorrType(GSM::Time currTime,
size_t chan)
{
static int tchh_subslot[26] = { 0,1,0,1,0,1,0,1,0,1,0,1,0,0,1,0,1,0,1,0,1,0,1,0,1,1 };
static int sdcch4_subslot[102] = { 3,3,3,3,0,0,2,2,2,2,3,3,3,3,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,2,2,2,2,
3,3,3,3,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,2,2,2,2 };
static int sdcch8_subslot[102] = { 5,5,5,5,6,6,6,6,7,7,7,7,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,6,6,6,6,7,7,7,7,0,0,0,0,
1,1,1,1,2,2,2,2,3,3,3,3,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,6,6,6,6,7,7,7,7,4,4,4,4 };
TransceiverState *state = &mStates[chan];
unsigned burstTN = currTime.TN();
unsigned burstFN = currTime.FN();
int subch;
switch (state->chanType[burstTN]) {
case NONE:
return OFF;
break;
case FILL:
return IDLE;
break;
case I:
// TODO: Are we expecting RACH on an IDLE frame?
/* if (burstFN % 26 == 25)
return IDLE;*/
if (mHandover[burstTN][0])
return RACH;
return TSC;
break;
case II:
subch = tchh_subslot[burstFN % 26];
if (subch == 1)
return IDLE;
if (mHandover[burstTN][0])
return RACH;
return TSC;
break;
case III:
subch = tchh_subslot[burstFN % 26];
if (mHandover[burstTN][subch])
return RACH;
return TSC;
break;
case IV:
case VI:
return cfg->ext_rach ? EXT_RACH : RACH;
break;
case V: {
int mod51 = burstFN % 51;
if ((mod51 <= 36) && (mod51 >= 14))
return cfg->ext_rach ? EXT_RACH : RACH;
else if ((mod51 == 4) || (mod51 == 5))
return cfg->ext_rach ? EXT_RACH : RACH;
else if ((mod51 == 45) || (mod51 == 46))
return cfg->ext_rach ? EXT_RACH : RACH;
else if (mHandover[burstTN][sdcch4_subslot[burstFN % 102]])
return RACH;
else
return TSC;
break;
}
case VII:
if ((burstFN % 51 <= 14) && (burstFN % 51 >= 12))
return IDLE;
else if (mHandover[burstTN][sdcch8_subslot[burstFN % 102]])
return RACH;
else
return TSC;
break;
case XIII: {
int mod52 = burstFN % 52;
if ((mod52 == 12) || (mod52 == 38))
return RACH; /* RACH is always 8-bit on PTCCH/U */
else if ((mod52 == 25) || (mod52 == 51))
return IDLE;
else /* Enable 8-PSK burst detection if EDGE is enabled */
return cfg->egprs ? EDGE : TSC;
break;
}
case LOOPBACK:
if ((burstFN % 51 <= 50) && (burstFN % 51 >=48))
return IDLE;
else
return TSC;
break;
default:
return OFF;
break;
}
}
void writeToFile(radioVector *radio_burst, size_t chan)
{
GSM::Time time = radio_burst->getTime();
std::ostringstream fname;
fname << chan << "_" << time.FN() << "_" << time.TN() << ".fc";
std::ofstream outfile (fname.str().c_str(), std::ofstream::binary);
outfile.write((char*)radio_burst->getVector()->begin(), radio_burst->getVector()->size() * 2 * sizeof(float));
outfile.close();
}
double Transceiver::rssiOffset(size_t chan)
{
if (cfg->force_rssi_offset)
return cfg->rssi_offset;
return mRadioInterface->rssiOffset(chan) + cfg->rssi_offset;
}
static SoftVector *demodAnyBurst_va(const signalVector &burst, CorrType type, int sps, int rach_max_toa, int tsc)
{
auto conved_beg = reinterpret_cast<const std::complex<float> *>(&burst.begin()[0]);
std::complex<float> chan_imp_resp[CHAN_IMP_RESP_LENGTH * d_OSR];
float ncmax;
const unsigned burst_len_bits = 148 + 8;
char demodded_softbits[burst_len_bits];
SoftVector *bits = new SoftVector(burst_len_bits);
if (type == CorrType::TSC) {
auto rach_burst_start = get_norm_chan_imp_resp(conved_beg, chan_imp_resp, &ncmax, tsc);
rach_burst_start = std::max(rach_burst_start, 0);
detect_burst_nb(conved_beg, chan_imp_resp, rach_burst_start, demodded_softbits);
} else {
auto normal_burst_start = get_access_imp_resp(conved_beg, chan_imp_resp, &ncmax, 0);
normal_burst_start = std::max(normal_burst_start, 0);
detect_burst_ab(conved_beg, chan_imp_resp, normal_burst_start, demodded_softbits, rach_max_toa);
}
float *s = &bits->begin()[0];
for (unsigned int i = 0; i < 148; i++)
s[i] = demodded_softbits[i] * -1;
for (unsigned int i = 148; i < burst_len_bits; i++)
s[i] = 0;
return bits;
}
#define USE_VA
#ifdef USE_VA
// signalvector is owning despite claiming not to, but we can pretend, too..
static void dummy_free(void *wData){};
static void *dummy_alloc(size_t newSize)
{
return 0;
};
#endif
/*
* Pull bursts from the FIFO and handle according to the slot
* and burst correlation type. Equalzation is currently disabled.
* returns 0 on success (bi filled), negative on error (bi content undefined):
* -ENOENT: timeslot is off (fn and tn in bi are filled),
* -EIO: read error
*/
int Transceiver::pullRadioVector(size_t chan, struct trx_ul_burst_ind *bi)
{
int rc;
struct estim_burst_params ebp;
float max = -1.0, avg = 0.0;
unsigned max_toa;
int max_i = -1;
signalVector *burst;
GSM::Time burstTime;
SoftVector *rxBurst;
TransceiverState *state = &mStates[chan];
bool ctr_changed = false;
double rssi_offset;
static complex burst_shift_buffer[625];
static signalVector shift_vec(burst_shift_buffer, 0, 625, dummy_alloc, dummy_free);
signalVector *shvec_ptr = &shift_vec;
/* Blocking FIFO read */
radioVector *radio_burst = mReceiveFIFO[chan]->read();
if (!radio_burst) {
LOGCHAN(chan, DTRXDUL, ERROR) << "ReceiveFIFO->read() returned no burst";
return -EIO;
}
/* Set time and determine correlation type */
burstTime = radio_burst->getTime() + cfg->ul_fn_offset;
CorrType type = expectedCorrType(burstTime, chan);
/* Initialize struct bi */
bi->nbits = 0;
bi->fn = burstTime.FN();
bi->tn = burstTime.TN();
bi->rssi = 0.0;
bi->toa = 0.0;
bi->noise = 0.0;
bi->idle = false;
bi->modulation = MODULATION_GMSK;
bi->tss = 0; /* TODO: we only support tss 0 right now */
bi->tsc = 0;
bi->ci = 0.0;
/* Debug: dump bursts to disk */
/* bits 0-7 - chan 0 timeslots
* bits 8-15 - chan 1 timeslots */
if (mWriteBurstToDiskMask & ((1<<bi->tn) << (8*chan)))
writeToFile(radio_burst, chan);
/* No processing if the timeslot is off.
* Not even power level or noise calculation. */
if (type == OFF) {
delete radio_burst;
return -ENOENT;
}
/* If TRX RF is locked/muted by BTS, send idle burst indications */
if (state->mMuted)
goto ret_idle;
/* Select the diversity channel with highest energy */
for (size_t i = 0; i < radio_burst->chans(); i++) {
float pow = energyDetect(*radio_burst->getVector(i), 20 * cfg->rx_sps);
if (pow > max) {
max = pow;
max_i = i;
}
avg += pow;
}
if (max_i < 0) {
LOGCHAN(chan, DTRXDUL, INFO) << "Received empty burst";
state->ctrs.rx_empty_burst++;
ctr_changed = true;
goto ret_idle;
}
/* Average noise on diversity paths and update global levels */
burst = radio_burst->getVector(max_i);
avg = sqrt(avg / radio_burst->chans());
if (type == IDLE) {
/* Update noise levels */
state->mNoises.insert(avg);
state->mNoiseLev = state->mNoises.avg();
}
rssi_offset = rssiOffset(chan);
bi->rssi = 20.0 * log10(rxFullScale / avg) + rssi_offset;
bi->noise = 20.0 * log10(rxFullScale / state->mNoiseLev) + rssi_offset;
if (type == IDLE)
goto ret_idle;
max_toa = (type == RACH || type == EXT_RACH) ?
mMaxExpectedDelayAB : mMaxExpectedDelayNB;
if (cfg->use_va) {
// shifted burst copy to make the old demod and detection happy
std::copy(burst->begin() + 20, burst->end() - 20, shift_vec.begin());
} else {
shvec_ptr = burst;
}
/* Detect normal or RACH bursts */
rc = detectAnyBurst(*shvec_ptr, mTSC, BURST_THRESH, cfg->rx_sps, type, max_toa, &ebp);
if (rc <= 0) {
if (rc == -SIGERR_CLIP) {
LOGCHAN(chan, DTRXDUL, INFO) << "Clipping detected on received RACH or Normal Burst";
state->ctrs.rx_clipping++;
ctr_changed = true;
} else if (rc != SIGERR_NONE) {
LOGCHAN(chan, DTRXDUL, INFO) << "Unhandled RACH or Normal Burst detection error";
state->ctrs.rx_no_burst_detected++;
ctr_changed = true;
}
goto ret_idle;
}
if (cfg->use_va) {
scaleVector(*burst, { (1. / (float)((1 << 14) - 1)), 0 });
rxBurst = demodAnyBurst_va(*burst, (CorrType)rc, cfg->rx_sps, max_toa, mTSC);
} else {
rxBurst = demodAnyBurst(*shvec_ptr, (CorrType)rc, cfg->rx_sps, &ebp);
}
bi->toa = ebp.toa;
bi->tsc = ebp.tsc;
bi->ci = ebp.ci;
/* EDGE demodulator returns 444 (gSlotLen * 3) bits */
if (rxBurst->size() == EDGE_BURST_NBITS) {
bi->modulation = MODULATION_8PSK;
bi->nbits = EDGE_BURST_NBITS;
} else { /* size() here is actually gSlotLen + 8, due to guard periods */
bi->modulation = MODULATION_GMSK;
bi->nbits = gSlotLen;
}
// Convert -1..+1 soft bits to 0..1 soft bits
vectorSlicer(bi->rx_burst, rxBurst->begin(), bi->nbits);
delete rxBurst;
delete radio_burst;
return 0;
ret_idle:
if (ctr_changed)
dispatch_trx_rate_ctr_change(state, chan);
bi->idle = true;
delete radio_burst;
return 0;
}
void Transceiver::reset()
{
for (size_t i = 0; i < mTxPriorityQueues.size(); i++)
mTxPriorityQueues[i].clear();
}
/**
* Matches a buffer with a command.
* @param buf a buffer to look command in
* @param cmd a command to look in buffer
* @param params pointer to arguments, or NULL
* @return true if command matches, otherwise false
*/
static bool match_cmd(char *buf,
const char *cmd, char **params)
{
size_t cmd_len = strlen(cmd);
/* Check a command itself */
if (strncmp(buf, cmd, cmd_len))
return false;
/* A command has arguments */
if (params != NULL) {
/* Make sure there is a space */
if (buf[cmd_len] != ' ')
return false;
/* Update external pointer */
*params = buf + cmd_len + 1;
}
return true;
}
void Transceiver::ctrl_sock_send(ctrl_msg& m, int chan)
{
ctrl_sock_state& s = mCtrlSockets[chan];
struct osmo_fd *conn_bfd = &s.conn_bfd;
s.txmsgqueue.push_back(m);
osmo_fd_write_enable(conn_bfd);
}
int Transceiver::ctrl_sock_write(int chan)
{
int rc;
ctrl_sock_state& s = mCtrlSockets[chan];
if (s.conn_bfd.fd < 0) {
return -EIO;
}
while (s.txmsgqueue.size()) {
const ctrl_msg m = s.txmsgqueue.front();
osmo_fd_write_disable(&s.conn_bfd);
/* try to send it over the socket */
rc = write(s.conn_bfd.fd, m.data, strlen(m.data) + 1);
if (rc == 0)
goto close;
if (rc < 0) {
if (errno == EAGAIN) {
osmo_fd_write_enable(&s.conn_bfd);
break;
}
goto close;
}
s.txmsgqueue.pop_front();
}
return 0;
close:
LOGCHAN(chan, DTRXCTRL, NOTICE) << "mCtrlSockets write(" << s.conn_bfd.fd << ") failed: " << rc;
return -1;
}
int Transceiver::ctrl_sock_handle_rx(int chan)
{
ctrl_msg cmd_received;
ctrl_msg cmd_to_send;
char *buffer = cmd_received.data;
char *response = cmd_to_send.data;
char *command, *params;
int msgLen;
ctrl_sock_state& s = mCtrlSockets[chan];
/* Attempt to read from control socket */
msgLen = read(s.conn_bfd.fd, buffer, sizeof(cmd_received.data)-1);
if (msgLen < 0 && errno == EAGAIN)
return 0; /* Try again later */
if (msgLen <= 0) {
LOGCHAN(chan, DTRXCTRL, NOTICE) << "mCtrlSockets read(" << s.conn_bfd.fd << ") failed: " << msgLen;
return -EIO;
}
/* Zero-terminate received string */
buffer[msgLen] = '\0';
/* Verify a command signature */
if (strncmp(buffer, "CMD ", 4)) {
LOGCHAN(chan, DTRXCTRL, NOTICE) << "bogus message on control interface";
return -EIO;
}
/* Set command pointer */
command = buffer + 4;
LOGCHAN(chan, DTRXCTRL, INFO) << "command is '" << command << "'";
if (match_cmd(command, "POWEROFF", NULL)) {
stop();
sprintf(response,"RSP POWEROFF 0");
} else if (match_cmd(command, "POWERON", NULL)) {
if (!start()) {
sprintf(response,"RSP POWERON 1");
} else {
sprintf(response,"RSP POWERON 0");
for (int i = 0; i < 8; i++) {
for (int j = 0; j < 8; j++)
mHandover[i][j] = false;
}
}
} else if (match_cmd(command, "HANDOVER", &params)) {
unsigned ts = 0, ss = 0;
sscanf(params, "%u %u", &ts, &ss);
if (ts > 7 || ss > 7) {
sprintf(response, "RSP HANDOVER 1 %u %u", ts, ss);
} else {
mHandover[ts][ss] = true;
sprintf(response, "RSP HANDOVER 0 %u %u", ts, ss);
}
} else if (match_cmd(command, "NOHANDOVER", &params)) {
unsigned ts = 0, ss = 0;
sscanf(params, "%u %u", &ts, &ss);
if (ts > 7 || ss > 7) {
sprintf(response, "RSP NOHANDOVER 1 %u %u", ts, ss);
} else {
mHandover[ts][ss] = false;
sprintf(response, "RSP NOHANDOVER 0 %u %u", ts, ss);
}
} else if (match_cmd(command, "SETMAXDLY", &params)) {
//set expected maximum time-of-arrival for Access Bursts
int maxDelay;
sscanf(params, "%d", &maxDelay);
mMaxExpectedDelayAB = maxDelay; // 1 GSM symbol is approx. 1 km
sprintf(response,"RSP SETMAXDLY 0 %d",maxDelay);
} else if (match_cmd(command, "SETMAXDLYNB", &params)) {
//set expected maximum time-of-arrival for Normal Bursts
int maxDelay;
sscanf(params, "%d", &maxDelay);
mMaxExpectedDelayNB = maxDelay; // 1 GSM symbol is approx. 1 km
sprintf(response,"RSP SETMAXDLYNB 0 %d",maxDelay);
} else if (match_cmd(command, "SETRXGAIN", &params)) {
int newGain;
sscanf(params, "%d", &newGain);
newGain = mRadioInterface->setRxGain(newGain, chan);
sprintf(response,"RSP SETRXGAIN 0 %d",newGain);
} else if (match_cmd(command, "NOISELEV", NULL)) {
if (mOn) {
float lev = mStates[chan].mNoiseLev;
sprintf(response,"RSP NOISELEV 0 %d",
(int) round(20.0 * log10(rxFullScale / lev)));
}
else {
sprintf(response,"RSP NOISELEV 1 0");
}
} else if (match_cmd(command, "SETPOWER", &params)) {
int power;
sscanf(params, "%d", &power);
power = mRadioInterface->setPowerAttenuation(power, chan);
mStates[chan].mPower = power;
sprintf(response, "RSP SETPOWER 0 %d", power);
} else if (match_cmd(command, "ADJPOWER", &params)) {
int power, step;
sscanf(params, "%d", &step);
power = mStates[chan].mPower + step;
power = mRadioInterface->setPowerAttenuation(power, chan);
mStates[chan].mPower = power;
sprintf(response, "RSP ADJPOWER 0 %d", power);
} else if (match_cmd(command, "NOMTXPOWER", NULL)) {
int power = mRadioInterface->getNominalTxPower(chan);
sprintf(response, "RSP NOMTXPOWER 0 %d", power);
} else if (match_cmd(command, "RXTUNE", &params)) {
// tune receiver
int freqKhz;
sscanf(params, "%d", &freqKhz);
mRxFreq = (freqKhz + cfg->freq_offset_khz) * 1e3;
if (!mRadioInterface->tuneRx(mRxFreq, chan)) {
LOGCHAN(chan, DTRXCTRL, FATAL) << "RX failed to tune";
sprintf(response,"RSP RXTUNE 1 %d",freqKhz);
}
else
sprintf(response,"RSP RXTUNE 0 %d",freqKhz);
} else if (match_cmd(command, "TXTUNE", &params)) {
// tune txmtr
int freqKhz;
sscanf(params, "%d", &freqKhz);
mTxFreq = (freqKhz + cfg->freq_offset_khz) * 1e3;
if (!mRadioInterface->tuneTx(mTxFreq, chan)) {
LOGCHAN(chan, DTRXCTRL, FATAL) << "TX failed to tune";
sprintf(response,"RSP TXTUNE 1 %d",freqKhz);
}
else
sprintf(response,"RSP TXTUNE 0 %d",freqKhz);
} else if (match_cmd(command, "SETTSC", &params)) {
// set TSC
unsigned TSC;
sscanf(params, "%u", &TSC);
if (TSC > 7) {
sprintf(response, "RSP SETTSC 1 %d", TSC);
} else {
LOGC(DTRXCTRL, NOTICE) << "Changing TSC from " << mTSC << " to " << TSC;
mTSC = TSC;
sprintf(response,"RSP SETTSC 0 %d", TSC);
}
} else if (match_cmd(command, "SETSLOT", &params)) {
// set slot type
int corrCode;
int timeslot;
sscanf(params, "%d %d", &timeslot, &corrCode);
if ((timeslot < 0) || (timeslot > 7)) {
LOGCHAN(chan, DTRXCTRL, NOTICE) << "bogus message on control interface";
sprintf(response,"RSP SETSLOT 1 %d %d",timeslot,corrCode);
return 0;
}
mStates[chan].chanType[timeslot] = (ChannelCombination) corrCode;
setModulus(timeslot, chan);
sprintf(response,"RSP SETSLOT 0 %d %d",timeslot,corrCode);
} else if (match_cmd(command, "SETFORMAT", &params)) {
// set TRXD protocol version
unsigned version_recv;
sscanf(params, "%u", &version_recv);
LOGCHAN(chan, DTRXCTRL, INFO) << "BTS requests TRXD version switch: " << version_recv;
if (version_recv > TRX_DATA_FORMAT_VER) {
LOGCHAN(chan, DTRXCTRL, INFO) << "rejecting TRXD version " << version_recv
<< " in favor of " << TRX_DATA_FORMAT_VER;
sprintf(response, "RSP SETFORMAT %u %u", TRX_DATA_FORMAT_VER, version_recv);
} else {
LOGCHAN(chan, DTRXCTRL, NOTICE) << "switching to TRXD version " << version_recv;
mVersionTRXD[chan] = version_recv;
sprintf(response, "RSP SETFORMAT %u %u", version_recv, version_recv);
}
} else if (match_cmd(command, "RFMUTE", &params)) {
// (Un)mute RF TX and RX
unsigned mute;
sscanf(params, "%u", &mute);
mStates[chan].mMuted = mute ? true : false;
sprintf(response, "RSP RFMUTE 0 %u", mute);
} else if (match_cmd(command, "_SETBURSTTODISKMASK", &params)) {
// debug command! may change or disappear without notice
// set a mask which bursts to dump to disk
int mask;
sscanf(params, "%d", &mask);
mWriteBurstToDiskMask = mask;
sprintf(response,"RSP _SETBURSTTODISKMASK 0 %d",mask);
} else {
LOGCHAN(chan, DTRXCTRL, NOTICE) << "bogus command " << command << " on control interface.";
sprintf(response,"RSP ERR 1");
}
LOGCHAN(chan, DTRXCTRL, INFO) << "response is '" << response << "'";
transceiver->ctrl_sock_send(cmd_to_send, chan);
return 0;
}
bool Transceiver::driveTxPriorityQueue(size_t chan)
{
int msgLen;
int burstLen;
struct trxd_hdr_v01_dl *dl;
char buffer[sizeof(*dl) + EDGE_BURST_NBITS];
uint32_t fn;
uint8_t tn;
// check data socket
msgLen = read(mDataSockets[chan], buffer, sizeof(buffer));
if (msgLen <= 0) {
LOGCHAN(chan, DTRXDDL, NOTICE) << "mDataSockets read(" << mDataSockets[chan] << ") failed: " << msgLen;
return false;
}
switch (msgLen) {
case sizeof(*dl) + gSlotLen: /* GSM burst */
burstLen = gSlotLen;
break;
case sizeof(*dl) + EDGE_BURST_NBITS: /* EDGE burst */
if (cfg->tx_sps != 4) {
LOGCHAN(chan, DTRXDDL, ERROR) << "EDGE burst received but SPS is set to " << cfg->tx_sps;
return false;
}
burstLen = EDGE_BURST_NBITS;
break;
default:
LOGCHAN(chan, DTRXDDL, ERROR) << "badly formatted packet on GSM->TRX interface (len="<< msgLen << ")";
return false;
}
dl = (struct trxd_hdr_v01_dl *) buffer;
/* Convert TDMA FN to the host endianness */
fn = osmo_load32be(&dl->common.fn);
tn = dl->common.tn;
/* Make sure we support the received header format */
switch (dl->common.version) {
case 0:
/* Version 1 has the same format */
case 1:
break;
default:
LOGCHAN(chan, DTRXDDL, ERROR) << "Rx TRXD message with unknown header version " << unsigned(dl->common.version);
return false;
}
LOGCHAN(chan, DTRXDDL, DEBUG) << "Rx TRXD message (hdr_ver=" << unsigned(dl->common.version)
<< "): fn=" << fn << ", tn=" << unsigned(tn) << ", burst_len=" << burstLen;
TransceiverState *state = &mStates[chan];
GSM::Time currTime = GSM::Time(fn, tn);
/* Verify proper FN order in DL stream */
if (state->first_dl_fn_rcv[tn]) {
int32_t delta = GSM::FNDelta(currTime.FN(), state->last_dl_time_rcv[tn].FN());
if (delta == 1) {
/* usual expected scenario, continue code flow */
} else if (delta == 0) {
LOGCHAN(chan, DTRXDDL, INFO) << "Rx TRXD msg with repeated FN " << currTime;
state->ctrs.tx_trxd_fn_repeated++;
dispatch_trx_rate_ctr_change(state, chan);
return true;
} else if (delta < 0) {
LOGCHAN(chan, DTRXDDL, INFO) << "Rx TRXD msg with previous FN " << currTime
<< " vs last " << state->last_dl_time_rcv[tn];
state->ctrs.tx_trxd_fn_outoforder++;
dispatch_trx_rate_ctr_change(state, chan);
/* Allow adding radio vector below, since it gets sorted in the queue */
} else if (chan == 0 && state->mFiller == FILLER_ZERO) {
/* delta > 1. Some FN was lost in the middle. We can only easily rely
* on consecutive FNs in TRX0 since it must transmit continuously in all
* setups. Also, osmo-trx supports optionally filling empty bursts on
* its own. In that case bts-trx is not obliged to submit all bursts. */
LOGCHAN(chan, DTRXDDL, INFO) << "Rx TRXD msg with future FN " << currTime
<< " vs last " << state->last_dl_time_rcv[tn]
<< ", " << delta - 1 << " FN lost";
state->ctrs.tx_trxd_fn_skipped += delta - 1;
dispatch_trx_rate_ctr_change(state, chan);
}
if (delta > 0)
state->last_dl_time_rcv[tn] = currTime;
} else { /* Initial check, simply store state */
state->first_dl_fn_rcv[tn] = true;
state->last_dl_time_rcv[tn] = currTime;
}
BitVector newBurst(burstLen);
BitVector::iterator itr = newBurst.begin();
uint8_t *bufferItr = dl->soft_bits;
while (itr < newBurst.end())
*itr++ = *bufferItr++;
addRadioVector(chan, newBurst, dl->tx_att, currTime);
return true;
}
bool Transceiver::driveReceiveRadio()
{
int rc = mRadioInterface->driveReceiveRadio();
if (rc == 0) {
usleep(100000);
return true;
}
if (rc < 0)
return false;
if (mForceClockInterface || mTransmitDeadlineClock > mLastClockUpdateTime + GSM::Time(216,0)) {
if (mForceClockInterface)
LOGC(DTRXCLK, NOTICE) << "Sending CLOCK indications";
mForceClockInterface = false;
return writeClockInterface();
}
return true;
}
void Transceiver::logRxBurst(size_t chan, const struct trx_ul_burst_ind *bi)
{
std::ostringstream os;
for (size_t i=0; i < bi->nbits; i++) {
if (bi->rx_burst[i] > 0.5) os << "1";
else if (bi->rx_burst[i] > 0.25) os << "|";
else if (bi->rx_burst[i] > 0.0) os << "'";
else os << "-";
}
double rssi_offset = rssiOffset(chan);
LOGCHAN(chan, DTRXDUL, DEBUG) << std::fixed << std::right
<< " time: " << unsigned(bi->tn) << ":" << bi->fn
<< " RSSI: " << std::setw(5) << std::setprecision(1) << (bi->rssi - rssi_offset)
<< "dBFS/" << std::setw(6) << -bi->rssi << "dBm"
<< " noise: " << std::setw(5) << std::setprecision(1) << (bi->noise - rssi_offset)
<< "dBFS/" << std::setw(6) << -bi->noise << "dBm"
<< " TOA: " << std::setw(5) << std::setprecision(2) << bi->toa
<< " C/I: " << std::setw(5) << std::setprecision(2) << bi->ci << "dB"
<< " bits: " << os;
}
bool Transceiver::driveReceiveFIFO(size_t chan)
{
struct trx_ul_burst_ind bi;
int rc;
if ((rc = pullRadioVector(chan, &bi)) < 0) {
if (rc == -ENOENT) { /* timeslot off, continue processing */
LOGCHAN(chan, DTRXDUL, DEBUG) << unsigned(bi.tn) << ":" << bi.fn << " timeslot is off";
return true;
}
return false; /* other errors: we want to stop the process */
}
if (!bi.idle && log_check_level(DTRXDUL, LOGL_DEBUG))
logRxBurst(chan, &bi);
switch (mVersionTRXD[chan]) {
case 0:
return trxd_send_burst_ind_v0(chan, mDataSockets[chan], &bi);
case 1:
return trxd_send_burst_ind_v1(chan, mDataSockets[chan], &bi);
default:
OSMO_ASSERT(false);
}
}
void Transceiver::driveTxFIFO()
{
/**
Features a carefully controlled latency mechanism, to
assure that transmit packets arrive at the radio/USRP
before they need to be transmitted.
Deadline clock indicates the burst that needs to be
pushed into the FIFO right NOW. If transmit queue does
not have a burst, stick in filler data.
*/
RadioClock *radioClock = (mRadioInterface->getClock());
if (mOn) {
//radioClock->wait(); // wait until clock updates
LOGC(DTRXCLK, DEBUG) << "radio clock " << radioClock->get();
while (radioClock->get() + mTransmitLatency > mTransmitDeadlineClock) {
// if underrun, then we're not providing bursts to radio/USRP fast
// enough. Need to increase latency by one GSM frame.
if (mRadioInterface->getWindowType() == RadioDevice::TX_WINDOW_USRP1) {
if (mRadioInterface->isUnderrun()) {
// only update latency at the defined frame interval
if (radioClock->get() > mLatencyUpdateTime + GSM::Time(USB_LATENCY_INTRVL)) {
mTransmitLatency = mTransmitLatency + GSM::Time(1,0);
LOGC(DTRXCLK, INFO) << "new latency: " << mTransmitLatency << " (underrun "
<< radioClock->get() << " vs "
<< mLatencyUpdateTime + GSM::Time(USB_LATENCY_INTRVL) << ")";
mLatencyUpdateTime = radioClock->get();
}
}
else {
// if underrun hasn't occurred in the last sec (216 frames) drop
// transmit latency by a timeslot
if (mTransmitLatency > mRadioInterface->minLatency()) {
if (radioClock->get() > mLatencyUpdateTime + GSM::Time(216,0)) {
mTransmitLatency.decTN();
LOGC(DTRXCLK, INFO) << "reduced latency: " << mTransmitLatency;
mLatencyUpdateTime = radioClock->get();
}
}
}
}
// time to push burst to transmit FIFO
pushRadioVector(mTransmitDeadlineClock);
mTransmitDeadlineClock.incTN();
}
}
radioClock->wait();
}
bool Transceiver::writeClockInterface()
{
int msgLen;
char command[50];
// FIXME -- This should be adaptive.
sprintf(command,"IND CLOCK %llu",(unsigned long long) (mTransmitDeadlineClock.FN()+2));
LOGC(DTRXCLK, INFO) << "sending " << command;
msgLen = write(mClockSocket, command, strlen(command) + 1);
if (msgLen <= 0) {
LOGC(DTRXCLK, ERROR) << "mClockSocket write(" << mClockSocket << ") failed: " << msgLen;
return false;
}
mLastClockUpdateTime = mTransmitDeadlineClock;
return true;
}
void *RxUpperLoopAdapter(TrxChanThParams *params)
{
char thread_name[16];
Transceiver *trx = params->trx;
size_t num = params->num;
free(params);
snprintf(thread_name, 16, "RxUpper%zu", num);
set_selfthread_name(thread_name);
OSMO_ASSERT(osmo_cpu_sched_vty_apply_localthread() == 0);
while (1) {
if (!trx->driveReceiveFIFO(num)) {
LOGCHAN(num, DTRXDUL, FATAL) << "Something went wrong in thread " << thread_name << ", requesting stop";
osmo_signal_dispatch(SS_MAIN, S_MAIN_STOP_REQUIRED, NULL);
break;
}
pthread_testcancel();
}
return NULL;
}
void *RxLowerLoopAdapter(Transceiver *transceiver)
{
set_selfthread_name("RxLower");
OSMO_ASSERT(osmo_cpu_sched_vty_apply_localthread() == 0);
while (1) {
if (!transceiver->driveReceiveRadio()) {
LOGC(DTRXDUL, FATAL) << "Something went wrong in thread RxLower, requesting stop";
osmo_signal_dispatch(SS_MAIN, S_MAIN_STOP_REQUIRED, NULL);
break;
}
pthread_testcancel();
}
return NULL;
}
void *TxLowerLoopAdapter(Transceiver *transceiver)
{
set_selfthread_name("TxLower");
OSMO_ASSERT(osmo_cpu_sched_vty_apply_localthread() == 0);
while (1) {
transceiver->driveTxFIFO();
pthread_testcancel();
}
return NULL;
}
void *TxUpperLoopAdapter(TrxChanThParams *params)
{
char thread_name[16];
Transceiver *trx = params->trx;
size_t num = params->num;
free(params);
snprintf(thread_name, 16, "TxUpper%zu", num);
set_selfthread_name(thread_name);
OSMO_ASSERT(osmo_cpu_sched_vty_apply_localthread() == 0);
while (1) {
if (!trx->driveTxPriorityQueue(num)) {
LOGCHAN(num, DTRXDDL, FATAL) << "Something went wrong in thread " << thread_name << ", requesting stop";
osmo_signal_dispatch(SS_MAIN, S_MAIN_STOP_REQUIRED, NULL);
break;
}
pthread_testcancel();
}
return NULL;
}
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