The original code handled both the fact where a TIME indication would be
missed (and thus the frame number be higher than previous + 1), as well
as the two cases for combined / non-combined CCCH.
The L1SAP code removed some of those bits, which I'm re-introducing
here.
This is a regression of the code compared to the existing
sysmoBTS code, where the L1 tells us whether its AGCH or
PCH. However, it was not used even in the old code, so
we can afford to simply put a #warning here.
In case of a RACH INDICATION on CCCH, we need to set CHAN_NR to
0x88 (RSL_CHAN_RACH). In other cases, chan_nr needs to reflect
the actual logical channel (TCH/SDCCH) on whcih the handover happened.
... in an effort to avoid introducing new/more spaghetti code
Also, use offsetof() instead of pointer calculation to determine
the start of GsmL1_Prim_t.u.phDataReq.msgUnitParam.u8Buffer
This first part moves BCCH message primitives from osmo-bts-sysmo to common
part. A new file "common/l1sap.c" is introduced to implement handling of
layer 1 messages from/to BTS model.
Spotted by Ciaby while debugging an audio issue. Do not
send anything to port==0 to the BSC/NITB. Look at the
upper bits of the speech_mode to determine if sending is
allowed. 0x1 means recv_only and all other modes allow us
to send.
Manually verified with a single phone call with LCR bridge
mode to send a CRCX early but a MDCX sendrecv later. The
audio starts to flow after the MDCX message. Virtual Addr
space didn't increase over 10 calls. The l1p_msg is freed
by the caller.
The code might not re-set speech_mode from one call to
another but if it is ever != 0 it can be expected that
the BSC will always set it. This is because we do not
(and don't want to) allocate the lchan dynamically on
every usage.
Fixes: SYS#2111
Use the new libosmo-abis API to query the session for the
statistics and then send it as a TLV element to the BSC.
This can be used to do post processing about the call. E.g
to figure out if no audio arrived at all.
The RSL_IE_MEAS_RES_NR is mandatory element with a minimum
of 5 octets (two for TL and three for the value). When we
establish a new channel we might not have had enough time
in a TDMA frame to calculate the average. The issue is not
easy to reproduce. At the point we receive the measurement
report we have two uplink measurements queued. As it is not
easy to reproduce and only occurs when a channel is new
I have decided to drop the message instead of sending made
up uplink measurement reports.
As of now lchan_build_rsl_ul_meas will always return 3 and
the condition will never be false.
Avoids: SYS#1781
The write_queue is designed to have a maximum amount of pending
messages and will refuse to take new messages when it has been
reached. The caller can decide if it wants to flush the queue
and add the message again, create a log. But in all cases the
ownership of the msgb has not been transferred. Fix the potential
memory leak in the failure situation.
Instead of handling primitives directly at layer 1 specific code,
osmo-bts handles primitives at common code.
When all primitive are moved, the l1sap interface will:
- receive PH-DATA indications and forward them to layer 2.
- check for RF link loss and notify BSC.
- receive TCH indications and forward them via RTP.
- receive PH-RTS indications and send PH-DATA requests with content
according to its logical channel.
- receive TCH-RTS indications and send TCH requests with content
received via RTP or loopback from TCH indications.
- send MPH-INFO requests to activate, deactivate and modify logical
channels and handle their confirms.
- receive MPH-INFO indications with measurements from tranceiver.
- forward received and transmitted PH-DATA to GSMTAP.
Use the standard RSL commands to order a logical channel
to use a fixed power level.
The code is not fully verified and there was a last minute
change to invoke bts_model_adjst_ms_pwr.
Currently the DSP is instructed to achieve a given uplink
power target but there are circumstances (e.g. EMV testing)
where we need more control over it. The "manual/software/osmo"
power control can only be implemented per TRX and not per
lchan. Add a very very basic control that checks the MS Power
used by the phone, the actual receive level and then adjust
the power.
The code doesn't take the history into account, if the phone
can not reach the requested power level the code will be stuck
(e.g. no timeout based on multiframes). It has a mode for a
fixed power control but no way to set it yet.
The change of the mode requires a restart of the software.
* Print the GPS FD that was opened (e.g. to see if it was
closed again)
* Print the state changes/expectations
* Print the correct to be applied. I wondered if I shouldo do
a cor = cor * -1.. cor = -cor.. or add CLOCK_CORR(err) macro
to use it inside the printf and correction and decided the
gain is not worth the risk.
Continously run the calibration process. Everytime we call the
reset function classify the outcome. In case of a failure schedule
the next command soon and otherwise wait several hours.
Remember if the process was started through the VTY or the run
loop. In case it can't be started immediately reset and schedule
a new run.
After a reboot the system might have been off for a long time
and the currently used value might be wrong. Remember that we
never ran the calibration and execute it on start.
We should only calibrate the clock if there is a GPS fix. Start
gpsd to determine if there is a fix or not. Work around trimble
decoding issues (sent an email upstream). We need to gain some
more experience to see if there memory leaks. We also need to
re-schedule the calibration depending on the outcome.
Change the sign before passing it as correction value. The error
is the difference between the TCXO and GPS. We need to correct by
the reverse of the error. This seems to be different depending on
the clock source we have.
This is a last minute untested change.
This runs the entire procedure for calibration with reasonable
error and success checking. It can be triggered from the VTY
of the sysmobts-mgr right now.
What is missing is to hook up with GPSD to check if the system
has a fix and provide a mode that will continously run the
calibration command.
The CTRL code should have used/extended the l1_if calibration
code. The sysmobts-mgr code first needs to determine if the
clock adjustment is necessary at all. This is done by first
resetting the counters, then waiting, then asking for the diff
and then applying the correction value. But the reference clock
is only set by the application comand.
Copy more code of l1if_rf_clock_info_reset to set the reference
clock as value. This is leaving some todos inside the code that
will be resolved as part of SYS#835.
Related: SYS#835
In the long run we will connect to GPSD and wait for a fix and
then run the calibration. The first step is to open (and re-open)
the control connection to the BTS.
As the connection is on localhost there should not be a computation
overhead to always have the connection open. When connecting assume
that the ASYNC connect worked directly as otherwise we get no
notification of the failure.
This looks like a "bug" of libosmo-abis that should check if the
socket has been connected or not.
This should handle OML channel combinations with CBCH and activate the
CBCH SAPI towards the DSP correspondingly. What is still missing is
sending any actual information over the CBCH in respons to the
PH-RTS.ind coming up from L1.
Read the serial number once and format it as a string. In
case no serial number is present -1 will be returned.
Manually tested with a slightly modified version. serial_nr
was the expected one.
Harald Welte
Andreas Eversberg