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GSMConfig.cpp
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GSMConfig.cpp
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/*
* Copyright 2008, 2009, 2010 Free Software Foundation, Inc.
*
* This software is distributed under multiple licenses; see the COPYING file in the main directory for licensing information for this specific distribuion.
*
* This use of this software may be subject to additional restrictions.
* See the LEGAL file in the main directory for details.
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.
*/
#include "GSMConfig.h"
#include "GSMTransfer.h"
#include "GSMLogicalChannel.h"
#include "GPRSExport.h"
#include <ControlCommon.h>
#include <Logger.h>
#include <NeighborTable.h>
#include <Reporting.h>
#include <Globals.h>
using namespace std;
using namespace GSM;
GSMConfig::GSMConfig()
:mCBCH(NULL),
mSI5Frame(UNIT_DATA),mSI6Frame(UNIT_DATA),
mSI1(NULL),mSI2(NULL),mSI3(NULL),mSI4(NULL),
mSI5(NULL),mSI6(NULL),
mStartTime(::time(NULL)),
mChangemark(0)
{
}
void GSMConfig::init()
{
mBand = (GSMBand)gConfig.getNum("GSM.Radio.Band");
mT3122 = gConfig.getNum("GSM.Timer.T3122Min");
regenerateBeacon();
}
void GSMConfig::start()
{
mPowerManager.start();
// Do not call this until the paging channels are installed.
mPager.start();
// If requested, start gprs to allocate channels at startup.
// Otherwise, channels are allocated on demand, if possible.
if (GPRS::configGprsChannelsMin() > 0) {
// Start gprs.
GPRS::gprsStart();
}
// Do not call this until AGCHs are installed.
mAccessGrantThread.start(Control::AccessGrantServiceLoop,NULL);
}
void GSMConfig::regenerateBeacon()
{
// FIXME -- Need to implement BCCH_CHANGE_MARK
gReports.incr("OpenBTS.GSM.RR.BeaconRegenerated");
mChangemark++;
// Update everything from the configuration.
LOG(NOTICE) << "regenerating system information messages, changemark " << mChangemark;
// BSIC components
mNCC = gConfig.getNum("GSM.Identity.BSIC.NCC");
LOG_ASSERT(mNCC<8);
mBCC = gConfig.getNum("GSM.Identity.BSIC.BCC");
LOG_ASSERT(mBCC<8);
// MCC/MNC/LAC
mLAI = L3LocationAreaIdentity();
std::vector<unsigned> neighbors = gNeighborTable.ARFCNList();
// if the neighbor list is emtpy, put ourselves on it
if (neighbors.size()==0) neighbors.push_back(gConfig.getNum("GSM.Radio.C0"));
// Now regenerate all of the system information messages.
// SI1
L3SystemInformationType1 *SI1 = new L3SystemInformationType1;
if (mSI1) delete mSI1;
mSI1 = SI1;
LOG(INFO) << *SI1;
L3Frame SI1L3(UNIT_DATA);
SI1->write(SI1L3);
L2Header SI1Header(L2Length(SI1L3.L2Length()));
mSI1Frame = L2Frame(SI1Header,SI1L3);
LOG(DEBUG) << "mSI1Frame " << mSI1Frame;
// SI2
L3SystemInformationType2 *SI2 = new L3SystemInformationType2(neighbors);
if (mSI2) delete mSI2;
mSI2 = SI2;
LOG(INFO) << *SI2;
L3Frame SI2L3(UNIT_DATA);
SI2->write(SI2L3);
L2Header SI2Header(L2Length(SI2L3.L2Length()));
mSI2Frame = L2Frame(SI2Header,SI2L3);
LOG(DEBUG) << "mSI2Frame " << mSI2Frame;
// SI3
L3SystemInformationType3 *SI3 = new L3SystemInformationType3;
if (mSI3) delete mSI3;
mSI3 = SI3;
LOG(INFO) << *SI3;
L3Frame SI3L3(UNIT_DATA);
SI3->write(SI3L3);
L2Header SI3Header(L2Length(SI3L3.L2Length()));
mSI3Frame = L2Frame(SI3Header,SI3L3,true);
LOG(DEBUG) << "mSI3Frame " << mSI3Frame;
// SI4
L3SystemInformationType4 *SI4 = new L3SystemInformationType4;
if (mSI4) delete mSI4;
mSI4 = SI4;
LOG(INFO) << *SI4;
LOG(INFO) << SI4;
L3Frame SI4L3(UNIT_DATA);
SI4->write(SI4L3);
//printf("SI4 bodylength=%d l2len=%d\n",SI4.l2BodyLength(),SI4L3.L2Length());
//printf("SI4L3.size=%d\n",SI4L3.size());
L2Header SI4Header(L2Length(SI4L3.L2Length()));
mSI4Frame = L2Frame(SI4Header,SI4L3,true);
LOG(DEBUG) << "mSI4Frame " << mSI4Frame;
#if GPRS_PAT | GPRS_TEST
// SI13. pat added 8-2011 to advertise GPRS support.
L3SystemInformationType13 *SI13 = new L3SystemInformationType13;
LOG(INFO) << *SI13;
L3Frame SI13L3(UNIT_DATA);
//printf("start=%d\n",SI13L3.size());
SI13->write(SI13L3);
//printf("end=%d\n",SI13L3.size());
//printf("SI13 bodylength=%d l2len=%d\n",SI13.l2BodyLength(),SI13L3.L2Length());
//printf("SI13L3.size=%d\n",SI13L3.size());
L2Header SI13Header(L2Length(SI13L3.L2Length()));
mSI13Frame = L2Frame(SI13Header,SI13L3,true);
LOG(DEBUG) << "mSI13Frame " << mSI13Frame;
#endif
// SI5
regenerateSI5();
// SI6
L3SystemInformationType6 *SI6 = new L3SystemInformationType6;
if (mSI6) delete mSI6;
mSI6 = SI6;
LOG(INFO) << *SI6;
SI6->write(mSI6Frame);
LOG(DEBUG) "mSI6Frame " << mSI6Frame;
}
void GSMConfig::regenerateSI5()
{
std::vector<unsigned> neighbors = gNeighborTable.ARFCNList();
// if the neighbor list is emtpy, put ourselves on it
if (neighbors.size()==0) neighbors.push_back(gConfig.getNum("GSM.Radio.C0"));
L3SystemInformationType5 *SI5 = new L3SystemInformationType5(neighbors);
if (mSI5) delete mSI5;
mSI5 = SI5;
LOG(INFO) << *SI5;
SI5->write(mSI5Frame);
LOG(DEBUG) << "mSI5Frame " << mSI5Frame;
}
CCCHLogicalChannel* GSMConfig::minimumLoad(CCCHList &chanList)
{
if (chanList.size()==0) return NULL;
CCCHList::iterator chan = chanList.begin();
CCCHLogicalChannel *retVal = *chan;
unsigned minLoad = (*chan)->load();
++chan;
while (chan!=chanList.end()) {
unsigned thisLoad = (*chan)->load();
if (thisLoad<minLoad) {
minLoad = thisLoad;
retVal = *chan;
}
++chan;
}
return retVal;
}
template <class ChanType> ChanType* getChan(vector<ChanType*>& chanList, bool forGprs)
{
const unsigned sz = chanList.size();
LOG(DEBUG) << "sz=" << sz;
if (sz==0) return NULL;
// (pat) Dont randomize for GPRS! GPRS requires that channels are returned
// in order for the initial channels allocated on C0.
// We shouldnt randomize at all because we want RR TCH to come from the
// front of the list and GPRS from the back.
unsigned pos = 0;
const char *configRandomize = "GSM.Channels.Randomize";
if (gConfig.defines(configRandomize)) {
if (forGprs) {
// If the parameter is 'required', the gConfig.remove fails, but dont print a zillion messages.
static bool once = true;
if (once) {
LOG(ALERT) << "Config parameter '" << configRandomize << "' is incompatible with GPRS, removed";
once = false;
}
gConfig.remove(configRandomize);
} else {
pos = random() % sz;
}
}
for (unsigned i=0; i<sz; i++, pos = (pos+1)%sz) {
LOG(DEBUG) << "pos=" << pos << " " << i << "/" << sz;
ChanType *chan = chanList[pos];
if (! chan->inUseByGPRS() && chan->recyclable()) return chan;
}
return NULL;
}
// Are the two channels adjacent?
template <class ChanType>
bool testAdjacent(ChanType *ch1, ChanType *ch2)
{
return (ch1->CN() == ch2->CN() && ch1->TN() == ch2->TN()-1);
}
// Return the goodness of this possible match of gprs channels.
// Higher numbers are gooder.
template <class ChanType>
int testGoodness(vector<ChanType*>& chanList, int lo, int hi)
{
int goodness = 0;
if (lo > 0) {
ChanType *ch1 = chanList[lo-1]; // ch1 is below to ch lo.
if (testAdjacent(ch1,chanList[lo])) {
// The best match is adjacent to other gprs channels.
if (ch1->inUseByGPRS()) { goodness += 2; }
// The next best is an empty adjacent channel.
else if (ch1->recyclable()) { goodness += 1; }
}
}
if (hi < (int)chanList.size()-1) {
ChanType *ch2 = chanList[hi+1]; // ch2 is above ch hi
if (testAdjacent(ch2,chanList[hi])) {
if (ch2->inUseByGPRS()) { goodness += 2; }
else if (ch2->recyclable()) { goodness += 1; }
}
}
return goodness;
}
// (pat) 6-20-2012: To increase the likelihood that GPRS channels will be adjacent,
// GSM RR channels will be allocated from the front of the channel list
// and GPRS from the end.
// This function allocates a group of channels for gprs.
// Look for the largest group of adjacent channels <= groupSize.
// Give preference to channels that are adjacent to channels already
// allocated for gprs, or to empty channels.
// Give second preference to groups near the end of the channel list.
// Return the allocated channels in the array pointed to by results and
// return number of channels found.
template <class ChanType>
static unsigned getChanGroup(vector<ChanType*>& chanList, ChanType **results)
{
const unsigned sz = chanList.size();
if (sz==0) return 0;
const bool backwards = true; // Currently we always search backwards.
// To search forwards, dont forget to invert besti,bestn below
ChanType *prevFreeCh = NULL; // unneeded initialization
int curN = 0; // current number of adjacent free channels.
int bestI=0, bestN=0; // best match
int bestGoodness = 0; // goodness of best match
for (unsigned i=0; i<sz; i++) {
ChanType *chan = chanList[backwards ? sz-i-1 : i];
if (chan->inUseByGPRS()) { continue; }
if (! chan->recyclable()) { continue; }
if (bestN == 0) {
bestI = i;
curN = bestN = 1;
bestGoodness = testGoodness(chanList,bestI,bestN);
} else {
if (testAdjacent<ChanType>(chan,prevFreeCh)) {
curN++; // chan is adjacent to prevCh.
int curGoodness = testGoodness(chanList,i,curN);
if (curN > bestN || (curN == bestN && curGoodness > bestGoodness)) {
// Best so far, so remember it.
bestN = curN;
bestI = i;
bestGoodness = curGoodness;
// optional early termination test
//if (bestN >= groupSize && bestIsAdjacent) { goto finished; }
}
} else {
curN = 0;
}
}
prevFreeCh = chan;
}
//finished:
for (int j = 0; j < bestN; j++) {
results[j] = chanList[bestI+j];
}
return bestN;
}
// Allocate a group of channels for gprs.
// See comments at getChanGroup.
int GSMConfig::getTCHGroup(int groupSize,TCHFACCHLogicalChannel **results)
{
ScopedLock lock(mLock);
int nfound = getChanGroup<TCHFACCHLogicalChannel>(mTCHPool,results);
for (int i = 0; i < nfound; i++) {
results[i]->debugGetL1()->setGPRS(true,NULL);
}
return nfound;
}
SDCCHLogicalChannel *GSMConfig::getSDCCH()
{
LOG(DEBUG);
ScopedLock lock(mLock);
LOG(DEBUG);
SDCCHLogicalChannel *chan = getChan<SDCCHLogicalChannel>(mSDCCHPool,0);
LOG(DEBUG);
if (chan) chan->open();
LOG(DEBUG);
return chan;
}
// (pat) By a very tortuous path, chan->open() calls L1Encoder::open() and L1Decoder::open(),
// which sets mActive in both and resets the timers.
TCHFACCHLogicalChannel *GSMConfig::getTCH(
bool forGPRS, // If true, allocate the channel to gprs, else to RR use.
bool onlyCN0) // If true, allocate only channels on the lowest ARFCN.
{
LOG(DEBUG);
ScopedLock lock(mLock);
//if (GPRS::GPRSDebug) {
// const unsigned sz = mTCHPool.size();
// char buf[300]; int n = 0;
// for (unsigned i=0; i<sz; i++) {
// TCHFACCHLogicalChannel *chan = mTCHPool[i];
// n += sprintf(&buf[n],"ch=%d:%d,g=%d,r=%d ",chan->CN(),chan->TN(),
// chan->inUseByGPRS(),chan->recyclable());
// }
// LOG(WARNING)<<"getTCH list:"<<buf;
//}
TCHFACCHLogicalChannel *chan = getChan<TCHFACCHLogicalChannel>(mTCHPool,forGPRS);
// (pat) We have to open it or set gprs mode before returning to avoid a race.
if (chan) {
// The channels are searched in order from low to high, so if the first channel
// found is not on CN0, we have failed.
//LOG(DEBUG)<<"getTCH returns"<<LOGVAR2("chan->CN",chan->CN());
if (onlyCN0 && chan->CN()) { return NULL; }
if (forGPRS) {
// (pat) Reserves channel for GPRS, but does not start delivering bursts yet.
chan->debugGetL1()->setGPRS(true,NULL);
return chan;
}
chan->open(); // (pat) LogicalChannel::open(); Opens mSACCH also.
gReports.incr("OpenBTS.GSM.RR.ChannelAssignment");
} else {
//LOG(DEBUG)<<"getTCH returns NULL";
}
LOG(DEBUG);
return chan;
}
template <class ChanType> size_t chanAvailable(const vector<ChanType*>& chanList)
{
size_t count = 0;
for (unsigned i=0; i<chanList.size(); i++) {
if (chanList[i]->inUseByGPRS()) { continue; }
if (chanList[i]->recyclable()) count++;
}
return count;
}
size_t GSMConfig::SDCCHAvailable() const
{
ScopedLock lock(mLock);
return chanAvailable<SDCCHLogicalChannel>(mSDCCHPool);
}
size_t GSMConfig::TCHAvailable() const
{
ScopedLock lock(mLock);
return chanAvailable<TCHFACCHLogicalChannel>(mTCHPool);
}
size_t GSMConfig::totalLoad(const CCCHList& chanList) const
{
size_t total = 0;
for (unsigned i=0; i<chanList.size(); i++) {
total += chanList[i]->load();
}
return total;
}
unsigned countActive(const SDCCHList& chanList)
{
unsigned active = 0;
const unsigned sz = chanList.size();
for (unsigned i=0; i<sz; i++) {
if (!chanList[i]->recyclable()) active++;
}
return active;
}
unsigned countActive(const TCHList& chanList)
{
unsigned active = 0;
const unsigned sz = chanList.size();
// Start the search from a random point in the list.
for (unsigned i=0; i<sz; i++) {
if (chanList[i]->inUseByGPRS()) continue;
if (!chanList[i]->recyclable()) active++;
}
return active;
}
unsigned countAvailable(const TCHList& chanList)
{
unsigned available = 0;
const unsigned sz = chanList.size();
// Start the search from a random point in the list.
for (unsigned i=0; i<sz; i++) {
if (chanList[i]->inUseByGPRS()) continue;
available++;
}
return available;
}
unsigned GSMConfig::SDCCHActive() const
{
return countActive(mSDCCHPool);
}
unsigned GSMConfig::TCHActive() const
{
return countActive(mTCHPool);
}
unsigned GSMConfig::TCHTotal() const
{
return countAvailable(mTCHPool);
}
unsigned GSMConfig::T3122() const
{
ScopedLock lock(mLock);
return mT3122;
}
unsigned GSMConfig::growT3122()
{
unsigned max = gConfig.getNum("GSM.Timer.T3122Max");
ScopedLock lock(mLock);
unsigned retVal = mT3122;
mT3122 += (random() % mT3122) / 2;
if (mT3122>(int)max) mT3122=max;
return retVal;
}
unsigned GSMConfig::shrinkT3122()
{
unsigned min = gConfig.getNum("GSM.Timer.T3122Min");
ScopedLock lock(mLock);
unsigned retVal = mT3122;
mT3122 -= (random() % mT3122) / 2;
if (mT3122<(int)min) mT3122=min;
return retVal;
}
void GSMConfig::createCombination0(TransceiverManager& TRX, unsigned TN)
{
// This channel is a dummy burst generator.
// This should not be applied to C0T0.
LOG_ASSERT(TN!=0);
LOG(NOTICE) << "Configuring dummy filling on C0T " << TN;
ARFCNManager *radio = TRX.ARFCN(0);
radio->setSlot(TN,0); // (pat) 0 => Transciever.h enum ChannelCombination = FILL
}
void GSMConfig::createCombinationI(TransceiverManager& TRX, unsigned CN, unsigned TN)
{
LOG_ASSERT((CN!=0)||(TN!=0));
LOG(NOTICE) << "Configuring combination I on C" << CN << "T" << TN;
ARFCNManager *radio = TRX.ARFCN(CN);
radio->setSlot(TN,1); // (pat) 1 => Transciever.h enum ChannelCombination = I
TCHFACCHLogicalChannel* chan = new TCHFACCHLogicalChannel(CN,TN,gTCHF_T[TN]);
chan->downstream(radio);
Thread* thread = new Thread;
thread->start((void*(*)(void*))Control::DCCHDispatcher,chan);
chan->open();
gBTS.addTCH(chan);
}
void GSMConfig::createCombinationVII(TransceiverManager& TRX, unsigned CN, unsigned TN)
{
LOG_ASSERT((CN!=0)||(TN!=0));
LOG(NOTICE) << "Configuring combination VII on C" << CN << "T" << TN;
ARFCNManager *radio = TRX.ARFCN(CN);
radio->setSlot(TN,7); // (pat) 7 => Transciever.h enum ChannelCombination = VII
for (int i=0; i<8; i++) {
SDCCHLogicalChannel* chan = new SDCCHLogicalChannel(CN,TN,gSDCCH8[i]);
chan->downstream(radio);
Thread* thread = new Thread;
thread->start((void*(*)(void*))Control::DCCHDispatcher,chan);
chan->open();
gBTS.addSDCCH(chan);
}
}
void GSMConfig::hold(bool val)
{
ScopedLock lock(mLock);
mHold = val;
}
bool GSMConfig::hold() const
{
ScopedLock lock(mLock);
return mHold;
}
#if ENABLE_PAGING_CHANNELS
// 5-27-2012 pat added:
// Routines for CCCH messages to add real paging channels.
// Added in the simplest possible way to avoid destabilizing anything.
// GPRS still needs a pretty major rewrite of the underlying CCCHLogicalChannel class
// to reduce the latency, but paging queues at least relieve the congestion on CCCH.
// In DRX [Discontinuous Reception] mode the MS listens only to a subset of CCCH based on its IMSI.
// This is a GPRS thing but dependent on the configuration of CCCH in our system.
// See: GSM 05.02 6.5.2: Determination of CCCH_GROUP and PAGING_GROUP for MS in idle mode.
void GSMConfig::crackPagingFromImsi(
unsigned imsiMod1000 // The phones imsi mod 1000, so just atoi the last 3 digits.
unsigned &paging_block_index, // Returns which of the paging ccchs to use.
unsigned &multiframe_index // Returns which 51-multiframe to use.
)
{
L3ControlChannelDescription mCC;
// BS_CCCH_SDCCH_COMB is defined in GSM 05.02 3.3.2.3;
int bs_cc_chans; // The number of ccch timeslots per 51-multiframe.
bool bs_ccch_sdcch_comb; // temp var indicates if sdcch is on same TS as ccch.
switch (mCC.mCCCH_CONF) {
case 0: bs_cc_chans=1; bs_ccch_sdcch_comb=false; break;
case 1: bs_cc_chans=1; bs_ccch_sdcch_comb=true; break;
case 2: bs_cc_chans=2; bs_ccch_sdcch_comb=false; break;
case 4: bs_cc_chans=3; bs_ccch_sdcch_comb=false; break;
case 6: bs_cc_chans=4; bs_ccch_sdcch_comb=false; break;
default:
LOG(ERR) << "Invalid GSM.CCCH.CCCH-CONF value:"<<mCC.mCCCH_CONF <<" GPRS will fail until fixed";
return NULL; // There will be no reliable GPRS service until you fix this.
}
// BS_PA_MFRMS is the number of 51-multiframes used for paging.
unsigned bs_pa_mfrms = mCC.getBS_PA_MFRMS();
// Here are some example numbers:
// We currently use CCCH_CONF=1 so cc_chans=1, so agch_avail=3.
// Since BS_CC_CHANS=1, then CCCH_GROUP is always 0.
// For BS_PA_MFRMS=2, BS_AG_BLKS_RES=2:
// N=2; tmp = imsi % 2; CCCH_GROUP = 0; PAGING_GROUP = imsi % 2;
// For BS_PA_MFRMS=2, BS_AG_BLKS_RES=1:
// N=4; tmp = imsi % 4; PAGING_GROUP = imsi % 4;
// For BS_PA_MFRMS=2, BS_AG_BLKS_RES=0:
// N=6; tmp = imsi % 6; PAGING_GROUP = imsi % 6;
// For BS_PA_MFRMS=3, BS_AG_BLKS_RES=0:
// N=9; tmp = imsi % 9; PAGING_GROUP = imsi % 9;
// Paging block index = PAGING_GROUP % BS_PA_MFRMS
// Multiframe index = PAGING_GROUP / pch_avail;
// correct multiframe when: multiframe_index == (FN div 51) % BA_PA_MFRMS
// From GSM 05.02 Clause 7 table 5 (located after sec 6.5)
unsigned agch_avail = bs_ccch_sdcch_comb ? 3 : 8;
// If you hit this assertion, go fix L3ControlChannelDescription
// to make sure you leave some paging channels available.
assert(agch_avail > mPCC.mBS_AG_BLKS_RES);
// GSM 05.02 6.5.2: N is number of paging blocks "available" on one CCCH.
// The "available" is in quotes and not specifically defined, but I believe
// they mean after subtracting out BS_AG_BLKS_RES, as per 6.5.1 paragraph v).
unsigned pch_avail = agch_avail - mPCC.mBS_AG_BLKS_RES;
unsigned Ntotal = pch_avail * bs_pa_mfrms;
unsigned tmp = (imsiMod1000 % (bs_cc_chans * Ntotal)) % Ntotal;
unsigned paging_group = tmp % Ntotal;
paging_block_index = paging_group / (Ntotal / bs_pa_mfrms);
// And I quote: The required 51-multiframe occurs when:
// PAGING_GROUP div (N div BS_PA_MFRMS) = (FN div 51) mod (BS_PA_MFRMS)
multiframe_index = paging_group / (Ntotal % bs_pa_mfrms);
}
void GSMConfig::sendPCH(const L3RRMessage& msg,unsigned imsiMod1000)
{
unsigned paging_block_index; // which of the paging ccchs to use.
unsigned multiframe_index; // which 51-multiframe to use.
crackPagingFromImsi(imsiMod1000,paging_block_index, multiframe_index);
assert(multiframe_index < sMax_BS_PA_MFRMS);
CCCHLogicalChannel* ch = getPCH(paging_block_index);
ch->mPagingQ[multiframe_index].write(new L3Frame((const L3Message&)msg,UNIT_DATA));
}
Time GSMConfig::getPchSendTime(imsiMod1000)
{
unsigned paging_block_index; // which of the paging ccchs to use.
unsigned multiframe_index; // which 51-multiframe to use.
crackPagingFromImsi(imsiMod1000,paging_block_index, multiframe_index);
assert(multiframe_index < sMax_BS_PA_MFRMS);
CCCHLogicalChannel* ch = getPCH(paging_block_index);
return ch->getNextPchSendTime(multiframe_index);
}
#endif
// vim: ts=4 sw=4