Instead of creating the sockets in the RSL code we will do this
in the CRCX_ACK, MDCX_ACK, DLCX_IND signal handler of gsm_04_08.
Introduce a handover signal so we can repatch the RTP sockets in
the gsm_04_08 as well.
The reason for this is quite simple: We want to make sure anyone
running a customized version of OpenBSC to operate a network will
have to release all custom modifiations to the source code.
The SS_LCHAN signals now always include the lchan_sig_data. For
the measurement report it will optionally include the measurement
report as well. Attempt to update all handlers of this signal as well
In case of a inflexible network it is better to hardcode
the rtp payload to a given type. E.g. when using AMR5.9 on
a TCH/F and TCH/H having the same payload is helpful. For
now this will be only used by the osmo-bsc.
Store the mapping from request to channel type in the GSM Network
struct as there is some policy involved with handling the request.
E.g. in a half rate network we don't want emergy calls to be getting
a TCH/F, or we want to have a different policy for early/late assignment
of phone calls. Update the table when creating the network and when
the neci is changed.
Allow the MS to use uplink discontinous transmission by
setting the right bit in the SystemInformation and set
DTXd/DTXu on the RSL channel commands.
This is configurable via dtx-used (0|1) on the network
level and still considered as experimental.
When the cell becomes visible we will be bombed with location
updating requests and to reduce the load on the network we should
assign as many channels for it as possible. During load peek it
is even more important than to have a spare voice channel and in
general the LU procedure is pretty fast.
Currently every SAPI release indication will trigger the channel. It
was possible that we had SAPI=3 and SAPI=0 allocated and we tried to
release the channel by sending a RF Channel Release, the BTS answered
with a RF Channel Release ACK but also sent the SAPI Release Indication
which triggered a channel release here. So it was possible that we
would have released a newly allocated channel because of the SAPI
release of the old connection.
This code now works by releasing all SAPIs from highest to lowest,
then sending a SACH Deactivate and finally releasing the channel. This
approach is in use on the on-waves/bsc-master.
1.) memset the gsm48_chan_desc to avoid sending dummy data
2.) According to the GSM08.58 9.3.5 the Mobile Allocation
shall be included but the empty (by setting the length
to zero).
3.) use msgb_tlv_put and calculate the length via the l3h
msgb_l3len and assign it.
This is a big change to the way we use the subscriber
connection. From now on it is is dynamically allocated
and we will slowly move from a 1:1 lchan to conn to
having more than one lchan per connection.
This is the first commit, the subscr_con* methods will
move to gsm_data once the use_count is removed from the
connection, the freeing of the connection will also change.
The Channel Activate might be sent to a different TRX than the
Immediate Assignment. So we need to make sure that the channel
is activated before we send the immediate assignment for the RACH.
Another reason for that is according to GSM 08.58 we should take
the frame number from the activate and use it for the starting
time inside the immediate assignment message. We obviously do not
do this yet.
The code assumes that the BTS will either respond with a CHAN ACK
or a CHAN NACK if not the lchan will remain in the request state.
Also, make sure the bit ordering in the pre-computed MA is correct,
as well as the cell channel description of the target cell being
present in the HO CMD.
We now compute the Cell Channel Description for SI 1 by bit-wise
OR of the ARFCN bitmask of each timeslot on all the TRX of the BTS.
Also, support generating a GSM 04.08 Channel Description IE for
the hopping case (with HSN/MAIO instead of ARFCN).
What's still missing now: Sending the 04.08 Mobile Allocation IE
When we issue a RF Channel Release in case of a failure we receive
RLL release indications after the channel was tearn down and we
issue another RF Channel Release as a result. The channel allocator
might have already allocated this channel and we release the channel
again with another MS on it.
Make rsl_rf_chan_release take an error argument and make it set
a new state in case of an error and change the RF Channel Release
ack to not set the state back to none in case of an error but wait
for a timeout that is a bit higher than T3111.
I tested this with removing the battery during a phonecall and
waiting for the channel failure. With this test we only send the
release once.
We assume that the lchan_free will initiate the release and
that when we handle the RLL release indication or the release
request as part of the shutdown sequence.
The current channel release has a couple of issues we will
need to fix in a set of upcoming commits.
The issues include:
1.) sending release twice
2.) reassigning the channel inbetween the relase..
This is an ip.access specific 08.58 oddity. It reports 0xffff
available paging buffers if the paging load is below the 12.21
CCCH LOAD INDICATION THRESHOLD.
We use 50, since that is what it reports if the threshold == 0.
For GSM V1 FR, the payload type is fixed to 3 in the RFC.
But for the other codecs, the payload type is dynamically assigned
between 96 and 127. Here, we use a static mapping internal to OpenBSC.
This patch is needed to make a rather old 139 unit (with sw version
120a002_v149b42d0) work with something else than FR codec. I also tested
this patch on a newer 139 (with sw version 120a352_v267b22d0) to make
sure it didn't add a regression. More testing with newer EDGE units
should be done by whoever has some of theses.
Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Currently our GSM04.11 code is closing the link for SAPI=3
and this would mean that the whole channel would be scheduled
for close... where we only want to close everything when freeing
the lchan or handling an error.
The logging/debugging code is generic enough to move it into libosmocore
while keeping OpenBSC specific definitions in openbsc itself.
This commit uses the logging support present in libosmocore-0.1.2,
you will have to update your library to this version.
This library is intended to collect all generic/common funcitionality
of all Osmocom.org projects, including OpenBSC but also OsmocomBB
The library currently includes the following modules:
bitvec, comp128, gsm_utils, msgb, select, signal, statistics, talloc, timer,
tlv_parse, linuxlist
msgb allocation error debugging had to be temporarily disabled as it depends on
'debug.c' functionality which at the moment remains in OpenBSC
If the lchan has AMR as speech codec we also need to send the
multirate config IE in the channel activation. This is already
done for the RSL Channel Modify message.
Holger Hans Peter Freyther
Harald Welte
Sylvain Munaut