bool CCCHLogicalChannel::sendGprsCcchMessage(NewPagingEntry *gprsMsg, GSM::Time &frameTime)
{
if (! gprsPageCcchSetTime(gprsMsg->mGprsClient,gprsMsg->mImmAssign,frameTime.FN())) {
return false;
}
L2LogicalChannelBase::l2sendm(*(gprsMsg->mImmAssign),L3_UNIT_DATA);
return true;
}
void RadioInterface::driveReceiveRadio() {
if (!mOn) return;
if (mReceiveFIFO.size() > 8) return;
pullBuffer();
GSM::Time rcvClock = mClock.get();
rcvClock.decTN(receiveOffset);
unsigned tN = rcvClock.TN();
int rcvSz = rcvCursor/2;
int readSz = 0;
const int symbolsPerSlot = gSlotLen + 8;
// while there's enough data in receive buffer, form received
// GSM bursts and pass up to Transceiver
// Using the 157-156-156-156 symbols per timeslot format.
while (rcvSz > (symbolsPerSlot + (tN % 4 == 0))*samplesPerSymbol) {
signalVector rxVector((symbolsPerSlot + (tN % 4 == 0)*samplesPerSymbol));
unRadioifyVector(rcvBuffer+readSz*2,rxVector);
GSM::Time tmpTime = rcvClock;
if (rcvClock.FN() >= 0) {
LOG(DEEPDEBUG) << "FN: " << rcvClock.FN();
radioVector* rxBurst = new radioVector(rxVector,tmpTime);
mReceiveFIFO.put(rxBurst);
}
mClock.incTN();
rcvClock.incTN();
//if (mReceiveFIFO.size() >= 16) mReceiveFIFO.wait(8);
LOG(DEBUG) << "receiveFIFO: wrote radio vector at time: " << mClock.get() << ", new size: " << mReceiveFIFO.size() ;
readSz += (symbolsPerSlot+(tN % 4 == 0))*samplesPerSymbol;
rcvSz -= (symbolsPerSlot+(tN % 4 == 0))*samplesPerSymbol;
tN = rcvClock.TN();
}
if (readSz > 0) {
//memcpy(rcvBuffer,rcvBuffer+2*readSz,sizeof(short)*2*(rcvCursor-readSz));
//rcvCursor = rcvCursor-2*readSz;
rcvCursor -= 2*readSz;
memmove(rcvBuffer,rcvBuffer+2*readSz,sizeof(short)*rcvCursor);
}
}
void RadioInterface::driveReceiveRadio() {
pullBuffer();
if (!rcvBuffer) {
return;}
GSM::Time rcvClock = mClock.get();
rcvClock.decTN(receiveOffset);
unsigned tN = rcvClock.TN();
int rcvSz = rcvBuffer->size();
int readSz = 0;
const int symbolsPerSlot = gSlotLen + 8;
// while there's enough data in receive buffer, form received
// GSM bursts and pass up to Transceiver
// Using the 157-156-156-156 symbols per timeslot format.
while (rcvSz > (symbolsPerSlot + (tN % 4 == 0))*samplesPerSymbol) {
signalVector rxVector(rcvBuffer->begin(),
readSz,
(symbolsPerSlot + (tN % 4 == 0))*samplesPerSymbol);
GSM::Time tmpTime = rcvClock;
if (rcvClock.FN() >= 0) {
LOG(DEEPDEBUG) << "FN: " << rcvClock.FN();
radioVector* rxBurst = new radioVector(rxVector,tmpTime);
mReceiveFIFO.write(rxBurst);
}
mClock.incTN();
rcvClock.incTN();
if (mReceiveFIFO.size() >= 16) mReceiveFIFO.wait(8);
LOG(DEEPDEBUG) << "receiveFIFO: wrote radio vector at time: " << mClock.get() << ", new size: " << mReceiveFIFO.size() ;
readSz += (symbolsPerSlot+(tN % 4 == 0))*samplesPerSymbol;
rcvSz -= (symbolsPerSlot+(tN % 4 == 0))*samplesPerSymbol;
tN = rcvClock.TN();
}
signalVector *tmp = new signalVector(rcvBuffer->size()-readSz);
rcvBuffer->segmentCopyTo(*tmp,readSz,tmp->size());
delete rcvBuffer;
rcvBuffer = tmp;
}
double Clock::systime(const GSM::Time& when) const
{
ScopedLock lock(mLock);
const double slotMicroseconds = (48.0 / 13e6) * 156.25;
const double frameMicroseconds = slotMicroseconds * 8.0;
int32_t elapsedFrames = when.FN() - mBaseFN;
if (elapsedFrames<0) elapsedFrames += gHyperframe;
double elapsedUSec = elapsedFrames * frameMicroseconds + when.TN() * slotMicroseconds;
double baseSeconds = mBaseTime.sec() + mBaseTime.usec()*1e-6;
double st = baseSeconds + 1e-6*elapsedUSec;
return st;
}
// (pat) BUG TODO: TO WHOM IT MAY CONCERN:
// I am not sure this routine works properly. If there is no CCCH message (an L3Frame)
// in the queue immediately after the previous frame is sent, an idle frame is inserted.
// If a subsequent valid CCCH message (paging response or MS initiated RR call or packet
// uplink request) arrives it will be blocked until the idle frame is sent.
// Probably doesnt matter for RR establishment, but for packets, the extra 1/4 sec
// delay (length of a 51-multiframe) is going to hurt.
// Note that a GPRS Immediate Assignment message must know when this CCCH gets sent.
// Right now, it has to guess.
// pats TODO: Send the transceiver an idle frame rather than doing it here.
// This should be architecturally changed to a pull-system instead of push.
// Among other things, that would let us prioritize the responses
// (eg, emergency calls go first) and let the packet Immediate Assignment message be
// created right before being sent, when we are certain when the
// Immediate Assignment is being sent.
void CCCHLogicalChannel::serviceLoop()
{
// build the idle frame
static const L3PagingRequestType1 filler;
static const L3Frame idleFrame(filler,UNIT_DATA);
#if ENABLE_PAGING_CHANNELS
L3ControlChannelDescription mCC;
unsigned bs_pa_mfrms = mCC.getBS_PA_MFRMS();
#endif
// prime the first idle frame
LogicalChannel::send(idleFrame);
// run the loop
while (true) {
L3Frame* frame = NULL;
#if ENABLE_PAGING_CHANNELS
// Check for paging message for this specific paging slot first,
// and if none, send any message in the mQ.
// The multiframe paging logic is from GSM 05.02 6.5.3.
// See documentation at crackPagingFromImsi() which is used to
// get the messages into the proper mPagingQ.
GSM::Time next = getNextWriteTime();
unsigned multiframe_index = (next.FN() / 51) % bs_pa_mfrms;
frame = mPagingQ[multiframe_index].read();
#endif
if (frame == NULL) {
frame = mQ.read(); // (pat) This is a blocking read; mQ is an InterThreadQueue
}
if (frame) {
// (pat) This tortuously calls XCCCHL1Encoder::transmit (see my documentation
// at LogicalChannel::send), which blocks until L1Encoder::mPrevWriteTime.
// Note: The q size is 0 while we are blocked here, so if we are trying
// to determine the next write time by adding the qsize, we are way off.
// Thats why there is an mWaitingToSend flag.
mWaitingToSend = true; // Waiting to send this block at mNextWriteTime.
LogicalChannel::send(*frame);
mWaitingToSend = false;
OBJLOG(DEBUG) << "CCCHLogicalChannel::serviceLoop sending " << *frame
<< " load: " << load() << " time: " << getNextWriteTime();
delete frame;
}
if (mQ.size()==0) {
// (pat) The radio continues to send the last frame forever,
// so we only send one idle frame here.
// Unfortunately, this slows the response.
// TODO: Send a static idle frame to the Transciever and rewrite this.
mWaitingToSend = true; // Waiting to send an idle frame at mNextWriteTime.
LogicalChannel::send(idleFrame);
mWaitingToSend = false;
OBJLOG(DEBUG) << "CCCHLogicalChannel::serviceLoop sending idle frame";
}
}
}
// (pat) This routine is going to be entirely replaced with one that works better for gprs.
// In the meantime, just return a number that is large enough to cover
// the worst case, which assumes that the messages in mQ also
// must go out on the paging timeslot.
Time GSM::CCCHLogicalChannel::getNextPchSendTime(unsigned multiframe_index)
{
L3ControlChannelDescription mCC;
// Paging is distributed over this many multi-frames.
unsigned bs_pa_mfrms = mCC.getBS_PA_MFRMS();
GSM::Time next = getNextWriteTime();
unsigned next_multiframe_index = (next.FN() / 51) % bs_pa_mfrms;
assert(bs_pa_mfrms > 1);
assert(multiframe_index < bs_pa_mfrms);
assert(next_multiframe_index < bs_pa_mfrms);
int achload = mQ.size();
if (mWaitingToSend) { achload++; }
// Total wait time is time needed to empty queue, plus the time until the first
// paging opportunity, plus 2 times the number of guys waiting in the paging queue,
// but it is all nonsense because if a new agch comes in,
// it will displace the paging message because the q is sent first.
// This just needs to be totally redone, and the best way is not to figure out
// when the message will be sent at all, but rather use a call-back to gprs
// just before the message is finally sent.
int multiframesToWait = 0;
if (achload) {
multiframesToWait = bs_pa_mfrms - 1; // Assume worst case.
} else {
// If there is nothing else waiting, we can estimate better:
while (next_multiframe_index != multiframe_index) {
multiframe_index = (multiframe_index+1) % bs_pa_mfrms;
multiframesToWait++;
}
}
int total = achload + multiframesToWait + bs_pa_mfrms * mPagingQ[multiframe_index].size();
int fnresult = (next.FN() + total * 51) % gHyperframe;
GSM::Time result(fnresult);
LOG(DEBUG) << "CCCHLogicalChannel::getNextSend="<< next.FN()
<<" load="<<achload<<LOGVAR(mWaitingToSend) <<" now="<<gBTS.time().FN()<<LOGVAR(fnresult);
return result;
}
Time GSM::CCCHLogicalChannel::getNextMsgSendTime() {
// Get the current frame.
// DAB GPRS - This should call L1->resync() first, otherwise, in an idle system,
// DAB GPRS - you can get times well into the past..
// (pat) Above is done in the underlying getNextWriteTime()
// Pats note: This may return the current frame number if it is ready to send now.
// 3-18-2012: FIXME: This result is not monotonically increasing!!
// That is screwing up GPRS sendAssignment.
GSM::Time next = getNextWriteTime();
int achload = load();
if (mWaitingToSend) { achload++; }
//old: GSM::Time result = next + (achload+3) * 51; // add one to be safe.
// (pat) TODO: We are adding a whole 51-multframe for each additional
// CCCH message, which may not be correct.
// Note: We dont need to carefully make sure the frame
// numbers are valid (eg, by rollForward), because this code is used by GPRS
// which is going to convert it to an RLC block time anyway.
int fnresult = (next.FN() + achload * 51) % gHyperframe;
GSM::Time result(fnresult);
LOG(DEBUG) << "CCCHLogicalChannel::getNextSend="<< next.FN()
<<" load="<<achload<<LOGVAR(mWaitingToSend) <<" now="<<gBTS.time().FN()<<LOGVAR(fnresult);
return result;
}