* copy-paste gsm_data_shared.* from OpenBSC master
* remove corresponding configure check and option
* remove .deb dependency
Actual refactoring with removal of unnecessary structures/parts, moving
common OpenBSC/OsmoBSC parts into libraries etc. are left for further
patches.
Current patch will make coexistence with *BSC easier and will simplify
our build infrastructure.
Change-Id: I9f004fb5c4c1db29d4792dfd281d388c7063da13
Related: OS#1923
* do not deactivate lchan when called with LCHAN_REL_ACT_REACT
* add fixme comment
It's unclear yet if any special steps are required for osmo-bts-trx so
let's just make it compatible with setups [1] using BS_AG_BLKS_RES != 1
for now.
Background: CCCH is auto activated by some OsmoBTS - before we receive
SI3, see 4a85828462. To accommodate for
that we deactivate CCCH in common/rsl.c, which triggers BTS-model
specific callback sapi_deactivate_cb() which updates parameters and
activates it again.
In case of osmo-bts-trx there is no auto-activation and (seems to be) no
need in special interaction with hw to activate channel (no
lchan_activate()) hence we can just skip entire
deactivate/setup/activate again routine.
[1] "channel-descrption bs-ag-blks-res N" in OpenBSC config file.
Related: OS#1575
Change-Id: I20b89ba1e43d1414180b083cd1e085eeffe5d513
If SI13 becomes unavailable in runtime than send 0-length message with
BCCH SAPI to PCU to indicate that SI13 have to be removed.
Change-Id: I72aef8bd98f21c4b5ea6eed21fc56b30d85bfc1b
Related: OS#2400
* explicitly set SAPI when sending data_ind to PCU
* drop unused receiving code for BCCH SAPI
* send SI13 when PCU is connected
* send SI13 when new SI is received
Change-Id: I9e83ef792585aa962f99897d9973cef12f186bcf
Related: OS#2400
* move TA related globals into phy_link
* move power loop related globals into phy_link
* prefix corresponding vty vars with osmotrx
Change-Id: I01d7c1abad67e51b886a4ecf2de072929d67da27
Related: OS#1848
Whether or not we are talking to an OpenBTS (SETBSIC) or OsmoTRX
(SETTSC) transceiver is a property of the phy_link, and not a property
of the BTS. Also, we *really, really* should never use global
variables. I'm very happy this is being cleaned up, finally.
Change-Id: I51aeb17661dfd63ff347f7b2c0d7ffa383ec814c
So far, L1SAP code is hiding RSL_CHAN_OSMO_PDCH from the bts specific
code below L1SAP. This is some kind of a hack/workaround, making code
and debug output / logs more difficult to understand.
So let's teach the lower layer how to treat RSL_CHAN_OSMO_PDCH and
remove the "hiding" code from the common l1sap.c code.
Change-Id: Iaaa833febe45b82166d3901f10cc5466a7591c19
That's mostly changes related to lc15bts-mgr from
https://gitlab.com/nrw_noa/osmo-bts branch nrw/litecell15 based on
eb5b7f80510b603579f7af6d7d5ead296c2fa260 commit.
I wanted to incorporate vty and hardcoded paths changes so we can use it
from this point without major backward-incompatible changes as a base
for future ports.
Change-Id: Iabbaedc84aaaa594150a4e5445c16dd1f6f89858
Related: SYS#3679
This patch adds a virtual physical layer designed to simulate the
Um air interface between BTS and MS. It does so by encapsulating MAC
blocks (Layer 2 PDUs) via GSMTAP and sending them through multicast UDP
streams, both in uplink and in downlink.
The purpose of this is enable testing without any radio hardware or
related licenses.
OsmocomBB has recently received as similar patch-set, adding a virty_phy
executable that can be run on a PC instead of the classic 'layer1'
firmware on a real phone.
Using GSMTAP means that one can use unmodified wireshark to decode the
messages exchanged on the virtual Um layer.
This code was originally started by Harald in January 2016, continued
by Sebastian Stumpf in late 2016 and early 2017, and finally completed
by Harald in July 2017.
Change-Id: I1bf7670975b1e367c1c62983020865a043542622
We want to always call l1if_tch_rx and l1sap_up in order to avoid losing triggering
events on the upper layer.
With this change, the upper layer will increase correctly seq + ts for
RTP. It will then send an RTP packet with only the header and no payload, which is
not correct but at least we avoid drifting the RTP clock. Upcoming patch
in the series solves this issue.
This patch assumes that we are not lossing data events from the physical
layer and that we receive an event every 20ms, even if the MS is not
transmitting due to DTX.
Depends on libosmocore If4ae20c22b881e94585dad710f17b9e37f77bf82
Change-Id: If5df8940fab833eb4e3ed851880b66987d356031
We used to have trx_meas_check_compute() and call that from the
bts-specific code in order to iterate over all timeslots and all lchans
in the timeslots if we have to send measurement reports. This was
executed once per frame, and created unequal CPU load over time, which
in turn might increase different per-ts jitter.
Since 2f028c4e2c in April 2017 we have
lchan_meas_check_compute(), which performs this on a per-lchan basis,
and hence CPU load is distributed over all active timeslots.
Change-Id: I6308cefe4a51e55719ea4ed4d613d3782b805c08
In some situations (e.g. when trying to do measurements/testing on the
BTS receiver / uplink) it is useful to have a way to disable the radio
link timeout and keep any channel open until deactivated, irrespective
of whether (valid) data is received or not.
This adds a related feature that can be activated by using an
osmocom-specific value of 0xff for the TS 12.21 Connection Failure
Criterion (9.4.14).
Change-Id: I736f21f6528db5c16fa80cdb905af20673797be5
* use GSM_BTS_HAS_SI() from OpenBSC instead of local copy
* arrange GSM_BTS_HAS_SI() checks to improve readability
* constify SI scheduler parameters
Change-Id: If74bc536fe7d2bfbc976c07d882151873ecda4f2
Related: OS#1660
This is resubmission of 9eeb0b1a13 with
errorneous use of talloc_asprintf() removed which should fix OS#2316.
Change-Id: I02ae6fffdc808c1ea14185dbb4a720d27a62d4bb
Related: OS#1614
Timing advance is currently not taken into account when computing
the measurement results, this commit fixes that
Change-Id: I2e0dfd13b53e8aa2822985f12bf2985e683ab553
This reverts commit 9eeb0b1a13.
This commit caused osmo-gsm-tester test runs for the sysmoBTS to fail with
SIGABRT consistently. See below redmine issues.
In osmo-bts-sysmo/l1_if.c, it uses talloc_asprintf to write to the char
version[MAX_VERSION_LENGTH]; talloc_asprintf() however is intended to work on
string buffers allocated by talloc, and attempts to reallocate version[].
Furthermore, it is not clear why the patch passes a 'data' arg to
app_info_sys_compl_cb() that is not used.
Hence I will revert this instead of trying to fix. Please resolve issues and
re-submit.
Related: OS#2316 OS#1614
Change-Id: I2c9fd5e6739c1750365c0241476ce4b1aa2df3d4
lchan_meas_check_compute() is a static function measurement.c.
In order to distribute the measurement result calculation events,
we need to be able to call lchan_meas_check_compute() from l1sap.c
Change-Id: Ideffe896613e0feda443bc13dac59dcdbbc605aa
add support for the TX/RX antenna-id feature that has been
introduced with release OCTSDR-2G-02.07.00-B1314-BETA. The
user can now set individual ID numbers for the TX and for
the RX antenna.
Change-Id: I872fe3c4d7b593358a4ce2f02cf0726611b9f3aa
In case a system has a high-gain external PA (like a 40dB PA) connected
externally, we cannot simply switch the transceiver to 0 dBm in
trx_init() only to then start the ramping at much lower levels once the
PHJ completes in trx_init_compl_cb(). The result would be a short
0 + 40 dBm spike followed by later ramping. We want to avoid that
spike, particularly its associated inrush current, so let's bring up the
board with smething very conservative like -50 dBm, and then ramp from
there.
Change-Id: I0ad91fce64f65e0213c9fcfde3390ace519055db
Fixes: SYS#3259
The macro L1SAP_IS_PTCCH(fn) only detects a PTCCH channel at fn%52 = 12,
the detection logic has been extended in order to detect PTCCH at fn%52 = 38.
See also 3GPP TS 05.02, Clause 7, Table 6 of 9
Change-Id: Ia6f3333121e5e920c5e1d562a081d0a1b58a1153
The ra parameter indicates the reason for the received rach
request. osmo-bts uses the ra parameter to determine if the
received rach request is packet access related. If yes,
osmo-bts will forward the request to the PCU.
In order to determine if the ra is packet related or not,
the higher 4 bits must be equel to 0x7 and at least one of
the lower 4 bits must be zero.
The current method lacks checking of the lower 4 bits. It
would also accept 0b01111111, which is reserved for future
use. This commit extends the check to take also the last
4 bits into accound.
See also: 3GPP TS 04.08, Table 9.9
Change-Id: I5eb88c42a91e158d9bfa4105ec9636035baf8959
Move rxgain and tx-attenuation (power) parameters from phy_link layer to phy_inst layer.
Rxgain and tx-attenuation parameters should be set for each phy_inst and send for each osmo-trx channel accordingly via control commands.
Change-Id: I4861a59d10d1ef91954e0c6ea265e66dec08844f
It seems more user friendly to look at a calibration table in terms of
the delta (positive or negative) compared to the nominal gain value,
rather than a collection of absolute gain values. It has the added
benefit that the (API/data model) user doesn't have to specify a gain
value for each ARFCN, but rather can rely on the default nominal gain in
absence of a calibration table for this specific unit.
Change-Id: I7311815902a88d2fc9d211cf4c62fa6fdc5e86ad
Improve state handling for for lock/unlock of OC_RADIO_CARRIER obj class. in
bts_model_chg_adm_state()
Change-Id: I034114beca95210169429d8ac1eb8648df12fc6c
Fix SID_FIRST_INH detection during speech and when SID_FIRST is interrupted by FACCH.
Fix SID_UPDATE_INH detection during silence and when SID_UPDATE is interrupted by FACCH.
Add a delay for SID_FIRST to appear at the right time after FACCH.
Fix extra byte sent in downlink for SID_FIRST and SID_UPDATE.
Change-Id: Ia811305e15541f2376005df736bd610e8b0d2f69
* make oml_tx_failure_event_rep() static and use osmo_signal_dispatch()
wrapped into oml_fail_rep() to trigger event reports outside of oml.c
instead of directly calling into OML layer
* remove unnecessary formatting from text messages
Related: OS#1615
Change-Id: I738555c547926e97b325ab53763c0076c42309bc
Currently the IP address where the control interface is bound
to is hardcoded to 127.0.0.1. This leads to problems with
multiple instances on one and the same machine. This commit
integrates the ctrl interface bind option into the VTY, so
that we can bind the ctrl interface to any IP address, just
like we do it with the VTY already.
Change-Id: If51e0c645c0789a4f4a8c51737fb81fb12f80829
* Unlike in AMR FR, in AMR HR incoming ONSET have to be treated
differently depending on whether we've recently sent SID UPDATE or
EMPTY frame. Split ST_SID_U FSM state into 2 states to accommodate for
that and make sure that additional states specific to AMR HR are not
used for AMR FR.
* Avoid sending E_VOICE and E_SID_U in corresponding states
as those do not initiate FSM state transitions anyway. This decrease
extra load from FSM signalling which otherwise would be triggered on
per-frame basis.
* Introduce separate signal for SID First P1 -> P2 transition to avoid
confusion with E_COMPL and E_SID_U initiated transitions from P1
state.
* Don't init DTX FSM for SDCCH channels.
Change-Id: I229ba39a38a223fada4881fc9aca35d3639371f8
Related: OS#1801
* add vty option to manually enable adaptive RTP jitter
buffering (disabled by default) on per-bts level
* use this setting on per-lchan level when setting jitter parameters via
vty at runtime
* check and log result of osmo_rtp_socket_set_param()
* note: older libosmo-abis will ignore this setting which will be
properly detected via return value
* if jitter buffer is disabled by configuring "rtp jitter-buffer 0" than
adaptive buffering is disabled as well but it will be used if jitter
buffer is set to different value for a givel lchan via vty
Change-Id: I489f3c419039f40b57c2ef0641c176478b8d3566
Having RTP metadata is useful for debugging - save Sequence Number and
Timestamp next to Marker bit from RTP header.
Change-Id: I359b3bcb74fbfc071547fe2f9d837829374fe997
Do not assume that 1 == BS_AG_BLKS_RES but take that information from
SI3. Note: due to current implementation quirks we activate channels
before SI3 obtained, than we deactivate channels upon receiving SI3 and
activate them again. This might not be necessary once we migrate to
proper OML state machines.
This affects lc15 and sysmo hw.
Change-Id: I11377b12680ac3b2f77f80e742b6f0af63fc9c1e
Related: OS#1575
Remove lchan deactivation related code duplication to facilitate future
use for dynamic CCCH re-activation.
Change-Id: Id0d3b19dbfaa16d1734321a07a6eb0355bfd77c9
Add explicit state for recursion (sending the different payload data in
response to the RTS request for same FN) and corresponding
transition. Remove ST_FACCH_V as with new explicit recursion handling it
becomes unreacheable. This makes it easier to maintain
preemption (interruption of current procedure due to FACCH or
Inhibition). This also reduces the number of possible transitions out of
each state thus reducing graph's cyclomatic complexity.
Change-Id: If39b68083d23a4a35f468a5d75f54eb733ebfd14
Introduce dtx_dl_amr_enabled() function which checks that DTX is enabled
and FSM is allocated and use it for all corresponding checks.
Change-Id: Ifa68b641265ed14f242765c85e40da2d1021a541
* re-introduce ST_ONSET_F to guard from repetitive ONSET messages in case
multiple FACCH occur duriing DTX silence period.
* produce ONSET event after both SID FIRST and UPDATE in case of AMR FR.
* always dispatch E_SID_F (SID FIRST) signal if in talkspurt.
* allow E_SID_* right after ONSET (zero-length talkspurt).
* add missing E_ONSET signal description.
* fix FSM transitions for AMR HR *Inhibited and First P*.
* fix incorrect return from l1if_tch_encode() in ONSET FACCH with
incoming SID UPDATE
Change-Id: I0e9033c5f169da46aed9a0d1295faff489778dcf
Related: OS#1801
It was moved to OpenBSC in 582e4f627674f46310a90d9061e82fb342051b42 as
it's used by both projects.
Change-Id: I8aba987e3cdaa840cf3e14913a8455b0ba759889
Handle ONSET cause by Voice and FACCH separately. In case of Voice we
have RTP payload which we have to cache and send later on in next
response to L1 RTS. FACCH have higher priority so it preempts both voice
and silence alike - hence we can send ONSET immediately but still have
to track previous state in order to get back to it gracefully.
This affects lc15 and sysmo hw as there's no FSM-based DTX
implementation for other models yet.
Note: this requires patch for OpenBSC which adds FACCH buffer to tch.dtx
struct.
Change-Id: Idba14dcd0cb12cd7aee86391fcc152c49fcd7052
Related: OS#1802
SDCCH occupy lchan 0..3 in combined configuration so for CCCH we've
always used lchan[4] - replace it with CCCH_LCHAN define and add
comment.
Change-Id: Ic5d742c292d638f119c6b4672120c1950adeb7f0
Use dedicated FSM to handle all DTX DL related events:
- add explicit checks if DTX DL is enabled (fixes regression for non-DTX
setup introduced in 654175f33b)
- fix handling of AMR CMI for SPEECH frames
- add FSM for DTX DL
- sync with corresponding changes in OpenBSC's
- handle FACCH-related DTX ONSET events
This affects both lc15 and sysmobts and requires corresponding change in
OpenBSC (Change-Id: Idac8609faf9b5ced818fde899ccfc6ed0c42e8fd).
Change-Id: I74a0b42cb34d525b8a70d264135e82994ca70d31
Use "impossible" dummy value to initialize last_fn to prevent dropping
of 1st RTP frame due to timestamp jump.
Fixes: OS#1803
Change-Id: I485af21f6761048d12dc7f5552fcdd46daf786ed
The multi-trx had to be removed because of build conflicts
with octphy header that lack the struct members for needed
to support multi-trx.
For details see the following revert-commits:
ed6b48e4a5c9a1f284ac
This commit reintroduces multi trx support and ads an ifdef
decision to ensure that header files without multi-trx
support still work.
Change-Id: I7f9b2906cc149c817183745b4c96bcc7f9ebdad0
Move code from tch.c (lc15, sysmo) into generic function which:
- check if talkspurt is happening
- cache SID if necessary or invalidate cache
- fill in CMR & CMI prefix
This also fixes the problem when SID FIRST was cached without sending
just like SID UPDATE instead of being sent right away.
Change-Id: I6c7016a54749abadeef4fd4f5b6f750b256fb916
* consolidate AMR CMR and CMI handling in common/amr.c
* use it in save_last_sid()
* remove dead code
* properly compute RTP payload length for AMR
* use save_last_sid() for FR & HR as well
* invalidate cached SID if SPEECH frame is received
Fixes: OS #1800, #1801
Change-Id: I5a1c1ad0b0a295a50e67775a4db85f1d331755ed
Note: this also require changes to properly link against libosmocodec -
see 2bb65be159dfdabf664fec569b343320301701b0 in libosmocore.
Change-Id: I96594cf3aa1013d505bd20069d5bf261d9a2aefb
If Marker bit is set than it's a talkspurt which we have to explicitly
indicate to L1 by first sending ONSET message and than actual voice
data in a separate message.
This change affect sysmobts and LC15 hw.
Change-Id: I88c41568bcb0d82699f617adc4ad192603dd1bb6
Related: OS#1750
Previously SID retransmission was scheduled incorrectly based on GSM
frames instead of voice frames. Fix this by using GSM Fn only as elapsed
time estimation:
* move saved SID retransmission into generic function from lc15 and sysmo
specific code
* split retransmission time check into separate generic function
* compute estimation for elapsed time since last retransmission using
GSM Fn
Change-Id: Ib054b458a7345d9ba40dba53754ca59ab099c8e8
Fixes: OS#1799
This reverts commit 06968beab9.
Theoretically, this patch makes a lot of sense, but in order to be able to
build osmo-bts-octphy until the headers version is clarified, revert use of
usCentreArfcn:
Above commit uses an usCentreArfcn member that is never defined in the history
of our octphy-2g-headers.git. This usCentreArfcn does exist in a code snapshot
OCTSDR-2G-02.05.00-B780-DEBUG, which is not (yet?) publicly available.
Also, the current headers version is apparently 02.07, though the octasic
version numbers have been known to cause confusion among osmocom folks.
This along with one other revert fixes this build problem:
make[3]: Entering directory '/n/s/octphy/git/osmo-bts/src/osmo-bts-octphy'
CC l1_oml.o
l1_oml.c: In function ‘l1if_trx_open’:
l1_oml.c:1350:13: error: ‘tOCTVC1_GSM_TRX_CONFIG’ has no member named ‘usCentreArfcn’
oc->Config.usCentreArfcn = plink->u.octphy.center_arfcn;
^
l1_oml.c:1352:13: error: ‘tOCTVC1_GSM_TRX_CONFIG’ has no member named ‘usCentreArfcn’
oc->Config.usCentreArfcn = trx->arfcn;
^
In file included from ../../include/osmo-bts/logging.h:5:0,
from l1_oml.c:33:
l1_oml.c:1365:13: error: ‘tOCTVC1_GSM_TRX_CONFIG’ has no member named ‘usCentreArfcn’
oc->Config.usCentreArfcn, oc->Config.usTsc, oc->RfConfig.ulRxGainDb,
^
Change-Id: I222766f6961f5f35aa3651e2907e3e908fe9a66e
Prepare for a dyn TS patch that needs to call rsl_tx_chan_act_ack() directly
without the rel_act_kind decision.
Add function rsl_tx_chan_act_acknack() to wrap rsl_tx_chan_act_ack() and
rsl_tx_chan_act_nack(). Move the decision whether to drop the ack/nack, based
on lchan->rel_act_kind, to the new function, losing some code dup.
Change all callers to use the new function; drop the two older ones from rsl.h
and make them static.
Note: for nack, the exception for dyn TS in PDCH mode was missing
(rsl_tx_chan_act_nack() had only the rel_act_kind != LCHAN_REL_ACT_RSL
condition, but should also have had the dyn TS exception as in
rsl_tx_chan_act_ack()). I already know that this exception will again be
removed in an upcoming commit, but for patch readability it logically makes
sense to add it here. To easily include the nack case, drop the check for which
pchan the dyn TS is operating as, because a rel_act_kind == LCHAN_REL_ACT_PCU
implies that it is either already in or trying to become PDCH mode.
Change-Id: I57ba60c670730c6d7877a6a9b96ece0a7679a0bb
Have one common ts_is_pdch(), placed in lchan.c, since this file is pretty
empty and pretty close to ts. Publish in gsm_data.h.
Remove the if-style implementation from l1sap.c, and instead implement in a
switch statement.
This prepares for upcoming ts_is_pdch() usage in ph_data_req() for sysmo and
lc15.
Change-Id: Ib78d663fdbac5a1d7053f1b9d543649b66da00e2
Interface structure between osmo-bts and osmo-pcu is updated with the
parameters to differentiate the type of RACH and further support 11 bit
RACH. The function prototype and definitions are changed accordingly.
Interface version number is increased.
Change-Id: I4f4c501b2d86d77c78de32a84b1804172ffb6f4d
Fill in values for BER, BTO, Link quality in L1SAP and send them to
PCU. Note: this increases the version of BTS <-> PCU protocol. It also
requires corresponding changes in libosmocore.
All BTS models provide measurements data unless direct DSP access for
PCU is enabled. For BTS-specific notes see below.
Octphy: conversion from sSNRDb to Link Quality uses formulae which works
in practice instead of what's documented for sSNRDb value. Subject to
change in future revisions.
TRX: C / I link quality estimator is not computed.
Change-Id: Ic9693a044756fb1c7bd2ff3cfa0db042c3c4e01c
Related: OS#1616
Existing interfaces are coded with the implicit expectation of using
a burst sequence length of 148, which is constant with GSM and GPRS.
That changes with EGPRS, where the burst length may be 444 due to
the use of 8-PSK instead of GMSK modulation.
Setup the interface to accept and return a length value with the
burst sequence. This allows 444 length bit vectors to/from the
EGPRS decoder/encoder. Length is explicitly used as a identifier for
8-PSK vs. GMSK modulated sequences.
Change-Id: I90b46b46b11b6ce280e7f8232d5a2fccec2d4f18
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
lchan_lookup in openbsc abis_rsl.c and rsl_lchan_lookup() rsl.c are the
same code, except for the log context, which is only set in abis_rsl.c.
The common code was factored out to gsm_data_shared.c in openbsc.git.
Use the *rc return code argument to keep the logging part in the newly
introduced thin wrapper lchan_lookup() in common/rsl.c. This also removes code
dup for logging
The rsl_lchan_lookup() implementation is removed from osmo-bts, so a recent
openbsc is needed to build this.
Change-Id: Ibc469b75e31560271be8633d524366442d27e6fb
Includes EGPRS specific convolutional codes, interleaving tables
and functions, burst mappings, training sequences, and parity
checks from 3GPP TS 44.060 needed to handle MCS codings 1-9.
Change-Id: Ie270398dd7a72f282ba53e646853d8de1eabee93
Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
Move the actual switch from static conf_lchans_for_pchan() into new 'public'
function conf_lchans_as_pchan(), adding an explicit pchan argument. This allows
passing a non-trivial pchan, for dynamic TS.
conf_lchans_as_pchan() now takes a pchan argument, so distinguish the naming
and drop the 'for_pchan' from conf_lchans_for_pchan(), which takes only a ts
argument.
Change-Id: I8e458501fff5503c243512aeb3469c12b1f2bbc4
We're about to introduce a new kind of dynamic channel, which will also use
parts of the ip.access mode dyn PDCH code paths. Make sure the general parts
have general names and mark ip.access specific parts as such.
Rename dyn_pdch_ts_[dis]connected() to cb_ts_[dis]connected().
Rename dyn_pdch_complete to ipacc_dyn_pdch_complete().
From cb_ts_[dis]connected(), factor out the current code into static
functions ipacc_dyn_pdch_[dis]connected() -- this will make sense once the
new dynamic kind is added to cb_ts_[dis]connected().
Change-Id: I7da5b7cb7b48572671f50e0dec97d9eec3083df1
Abstract code for checking/setting lchan's UL SID flag and RTP Marker
into generic function and use it for LC15 and sysmoBTS.
Change-Id: Ica5392e92bab29164711163e7b01adb174272883
Related: OS#1750
React on IPAC PDCH ACT and DEACT messages and invoke the PCU and bts_model_ts_*
APIs to effect switchover. The dyn PDCH interaction is described in the comment
to rsl_rx_dyn_pdch(), the main entry point for PDCH switchover.
In case the bts_model_ts_* are not implemented (or return other errors),
reply with an IPAC PDCH ACT/DEACT NACK.
Add callbacks that mark steps in the PDCH switchover process,
dyn_pdch_ts_disconnected(), dyn_pdch_ts_connected() and dyn_pdch_complete().
Add hooks in l1sap.c on channel activation and release confirmation, to call
dyn PDCH callbacks.
BTS dyn PDCH implementations should invoke dyn_pdch_ts_disconnected() and
dyn_pdch_ts_connected() when bts_model_ts_disconnect() or
bts_model_ts_connect() are called, respectively. (upcoming for sysmoBTS)
Change-Id: Id2f5f77121a65d6c14eac127b3d4fb50e97a77ab
Enhance bts_model_ API in preparation of dyn PDCH switching. These will be used
to re-connect a TCH/F_PDCH TS in a different mode: either as TCH/F or as PDCH.
All implementations so far return -ENOTSUP, and thus will cause a IPAC PDCH ACT
or DEACT *NACK* to be sent to the BSC as soon as these messages are handled.
Also add stubs in tests.
Change-Id: I21e60c028a1333431c3ed000f788b654d1170b0d
Previously software activation could have been reported multiple times
which broke proper BTS init. Introduce guard variable to ensure
reporting happens only once.
Note: this is just minimal workaround - ideally proper OML state machine
should be implemented.
Change-Id: Ifffbdb756bc5d2864f985c01a3299b839c4de7af
Related: OS#1648
We have seen that the DSP time to time rejects PTCCH message from BTS due to invalid block number.
As a result, we patched FN2PTCCHBLOCK calculation according TS 45.0002 Table 6.
Change-Id: I8be1c8b9159c94788857c6de5440a418739f1212
There is implicit invariant in trx_phy_instance() which is actively used
by various hw-specific implementations to get TRX's phy instance. Let's
make sure there's explicit assertion for this because there's been
segfaults in the past related to it.
I had accidently bumped the version as I thought that osmo_ph_pres_info_type
was part of the ABI. It is not an only internal to the BTS. Revert
this part of the change.
Previously osmo-bts-octphy have not provided in-band presence
information which cause off-by-one errors and misinterpretation of
ph_data_ind by PCU. This fixed now by adding support for explicitly
passing PH-DATA presence info. Corresponding check and in-band passing
of presence information are removed.
Note: this requires libosmocore version with osmo_ph_pres_info_type
support integrated.
[hfreyther/max: Remove + 1 from the decoded length]
In some cases we'd like to run multiple instances of osmo-bts on a
single machine. This is the case where we a multi-TRX PHY is to be used
for several BTSs, or in case osmo-bts-trx has multple SDRs attached.
This wa currently prevented by having a hard-coded PCU socket path
and telnet port, which are now configurable via VTY / config file
itself.
It remains up to the individual BTS hardware models to decide
whether or not to register those commands (depending on whether they
support the feature) via cfg_bts_auto_band_cmd / cfg_bts_no_auto_band_cmd
At the time the phy link / phy instance level VTY configuration
commands are parsed, we did not yet call l1if_open() and thus
pinst->u.{lc15,sysmobts}.hdl == NULL.
PHY or PHY instance specific configuration must thus be stored inside
the phy_link or phy_instance itself, and not inside the (not yet
existing) handle.
We solve this by moving around some parameters:
* clk_use_eeprom/clk_cal/clk_src/calib_path get replicated in
phy_instance
* min_qual_{rach,norm} are moved into the generic part (which means
that osmo-bts-octphy and osmo-bts-trx should also implement them)
Due to the changes introduced by the phy_link API, it's not easy to set
the default DSP trace flags via a command line argument anymore. We now
rather introduce a persitent VTY configuration command, by which the
default DSP tracing configuration can be set (for each PHY).
The persistent trace flags are stored in the phy_instance, while the
current operational run-time flags are in fl1h->phy_instance.
This includes changes required for
* shared main() function accross all BTS models
* use of the new phy_link / phy_instance infrastructure as the basis
for true multi-TRX operation
When the oml_link is down or not yet established, we currently lost
any OML messages that were scheduled for transmission to the BSC. Let's
prevent that by keeping a queue of OML messages, which is drained at the
time the OML link comes up again.
t200_ms is an unsigned int [7] array, while the oml_default_t200_ms was
an uint8_t[7] array, which we memcpy() to the former as default
initializer. Fix this by turning oml_default_t200_ms into unsigned int,
too.
Instead of limiting the number of TRX at VTY to the actual number of
supported TRX, VTY allows to configure any possible number of TRX. If a
TRX is configured, which is not supported by BTS model, an error message is
returned, which states that the given TRX is not supported.
MS uplink power control is required in pretty much any BTS, and we
cannot assume that they PHY / L1 will always take care of it by
itself. So the correspondign code is moved to common/power_control.c
and called from the generic part of L1SAP.
The corresponding VTY paramter has been moved from the sysmobts-specific
trx VTY node to the common BTS VTY node.
There are three transitions:
1. LCHAN_CIPH_NONE -> LCHAN_CIPH_RX_REQ -> LCHAN_CIPH_RX_CONF
It is used to enable ciphering in RX (uplink) direction only.
2. LCHAN_CIPH_RX_CONF -> LCHAN_CIPH_RX_CONF_TX_REQ -> LCHAN_CIPH_RXTX_CONF
It is used to additionally enable ciphering in TX (downlink) direction.
3. LCHAN_CIPH_NONE -> LCHAN_CIPH_RXTX_REQ -> LCHAN_CIPH_RX_CONF_TX_REQ
-> LCHAN_CIPH_RXTX_CONF
It is used to enable ciphering in both TX and RX directions. This is used
when the channel is activated with encryption already enabled. (assignment
or handover)
In order to follow the order of these transitions, the RX direction must
always be set before the TX direction.
If no cipher key is set (A5/0), ciphering is set to ALG 0, but lchan cipher
state remains at LCHAN_CIPH_NONE.
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.
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.
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.
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.
bts_ctrl_lookup.c: In function 'bts_controlif_setup':
bts_ctrl_lookup.c:97:2: warning: implicit declaration of function 'bts_ctrl_cmds_install' [-Wimplicit-function-declaration]
rc = bts_ctrl_cmds_install(bts);
^
libosmo-abis doesn't make it easy to have these parameters
as const.. just declare it non-const in the api. We pass
a static string but we know it will not be modified.
We use the completion call-back from L1 to compare the instructed
TRX board output power with the actual value as reported back from
L1.
Right now we only print an error message in case the values disagree.
In the future we might want to either use that value as part of our
calculation or send an OML alarm report to the BSC.
Using this control interface, an external program can request
attentuation of the transmitter for thermal management reasons. The
external application doesn't have to know anthing about the actual
transmit power, but it can just configure a certian value of milli-dB
(1/10000 bel) and update (increase/decrease) that value depending on
the thermal environment.
In order to support transmit power reduction by thermal management
as well as the variety of new internal / external PA configurations
of BTSs, we need a slightly more complex system.
Also, as at high power a single dB can be quite a big difference,
we are now doing all computations in milli-dB(m), i.e. 1/10000 bel.
Ramping is now used both for up and down ramping, as that is useful in
cases where you want to gracefully shut down a cell by shrinking its
radius, gradually handing over subscribers to neighboring cells.
Furthermore, this code is becoming part of the 'common' codebase, as it
is not really specific to how sysmobts is working.
The user can specify a single aggregate value for external system
gain/attenuation. Let's say you have 1dB loss of antenna cable, so you
can put that as 'user-gain -1' into the config, which means that a
'transmit power of 20dBm' will be compensatet for that and the TRX is
instructed to output 21dBm to compensate the cable loss. Similarly,
external PAs can be described by a positive user-gain.
One of the next steps will be to communicate those values and the
nominal power capability of the specific BTS to the BSC, so the BSC will
automatically show correct signal levels in the VTY and log files.
The code includes provisions for future extensions regarding
* an external and an internal PA with calibration tables
* a thermal attenuation setting to be controlled by the site manager
Extend the router to verify that the message received is
properly encoded. The code can deal with the basic structure
of ETSI OML and vendor specific messages for ip.access and
the osmocom project.
Fixes:
../../include/osmo-bts/oml.h:8:42: warning: ‘struct gsm_bts’ declared inside parameter list [enabled by default]
int down_oml(struct gsm_bts *bts, struct msgb *msg);
^
../../include/osmo-bts/oml.h:8:42: warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default]
../../include/osmo-bts/oml.h:12:52: warning: ‘struct gsm_abis_mo’ declared inside parameter list [enabled by default]
int oml_mo_send_msg(struct gsm_abis_mo *mo, struct msgb *msg, uint8_t msg_type);
^
../../include/osmo-bts/oml.h:13:31: warning: ‘struct gsm_abis_mo’ declared inside parameter list [enabled by default]
int oml_mo_opstart_ack(struct gsm_abis_mo *mo);
^
../../include/osmo-bts/oml.h:14:32: warning: ‘struct gsm_abis_mo’ declared inside parameter list [enabled by default]
int oml_mo_opstart_nack(struct gsm_abis_mo *mo, uint8_t nack_cause);
^
../../include/osmo-bts/oml.h:15:32: warning: ‘struct gsm_abis_mo’ declared inside parameter list [enabled by default]
int oml_mo_statechg_ack(struct gsm_abis_mo *mo);
^
../../include/osmo-bts/oml.h:16:33: warning: ‘struct gsm_abis_mo’ declared inside parameter list [enabled by default]
int oml_mo_statechg_nack(struct gsm_abis_mo *mo, uint8_t nack_cause);
^
../../include/osmo-bts/oml.h:19:29: warning: ‘struct gsm_abis_mo’ declared inside parameter list [enabled by default]
int oml_mo_state_chg(struct gsm_abis_mo *mo, int op_state, int avail_state);
^
../../include/osmo-bts/oml.h:22:31: warning: ‘struct gsm_abis_mo’ declared inside parameter list [enabled by default]
void oml_mo_state_init(struct gsm_abis_mo *mo, int op_state, int avail_state);
^
../../include/osmo-bts/oml.h:26:10: warning: ‘struct gsm_abis_mo’ declared inside parameter list [enabled by default]
int success);
^
../../include/osmo-bts/oml.h:29:33: warning: ‘struct gsm_abis_mo’ declared inside parameter list [enabled by default]
int oml_tx_state_changed(struct gsm_abis_mo *mo);
^
../../include/osmo-bts/oml.h:31:33: warning: ‘struct gsm_abis_mo’ declared inside parameter list [enabled by default]
int oml_mo_tx_sw_act_rep(struct gsm_abis_mo *mo);
^
../../include/osmo-bts/oml.h:36:4: warning: ‘struct gsm_abis_mo’ declared inside parameter list [enabled by default]
uint8_t cause);
For LCR and other systems without out-of-band information we need
to indicate the CMR. Not every air message will include the mode
and we sent a stream that had the CMR set and not-set. This lead
to the AudioCodes MGW only playing every second frame.
Remember the last used mode and initialize it to _NONE when we
receive the multirate config. In case of a real error we will
still use AMR_CMR_NONE.
The initial patch is from Harald. I have added the initialization
and moving of the defines to amr.h.
Manually verified by enabling AMR5.9 and looking at two RTP
packages in sequence. In both cases the CMR was 2. I have looked
at "amr.nb.cmr != 2" in wireshark and only found the MGCP dummy
packet.
Initialize the libosmo-abis VTY nodes more early so we can parse
the config file that was created by "write". Introduce abis_init
to initialize the libosmo-abis and modify abis_open to re-use an
existing line. Update the comments. This has only been tried with
the sysmobts-remote on x86. A TCP connection is opened toward the
configured BSC.
Fixes: SYS#285
These routines do not pass the gsm_abis_mo and parsing the FOM
header of the msg does not seem to be a good idea either. Pass
in the OML object so that the model code can determine what the
void pointer is.
The BTS layer needs to inform the handover code when an access
burst has been received. In turn the handover layer will ask the
bts to modify the channel, it will schedule the physical information
inform the BSC with the HANDOVER DETECTION and waits for the BTS
layer to inform it about the first received frame to stop a timer.
Currently, the AGCH queue length is not limited. This can lead to
large delays and network malfunction if there are many IMM.ASS.REJ
messages.
This patch adds two features:
- Don't accept msgs from the RSL layer when the queue is way too
full (safety measure, mainly if bts_ccch_copy_msg() is not being
called by the L1 layer, currently hard coded to 1000 messages)
- Selectively drop IMM.ASS.REJ from the queue output depending on the
queue length
Ticket: SYS#224
Sponsored-by: On-Waves ehf
This patch extends paging_gen_msg() by adding an output parameter
is_empty that is true, if only a paging message with dummy entries
has been placed into buffer. This feature is then used by
bts_ccch_copy_msg() to insert an AGCH message if is_empty is true.
Ticket: SYS#224
Sponsored-by: On-Waves ehf
Counters are added for the following events (use VTY show to query):
- Dropped IMMEDIATE ASSIGN REJECT messages
- Merged IMMEDIATE ASSIGN REJECT messages
- Rejected AGCH messages
- Use of PCH (non-reserved) for AGCH messages
- Use of AGCH (reserved) for AGCH messages
Sponsored-by: On-Waves ehf
This patch adds a function bts_update_agch_max_queue_length()
to compute a limit of the AGCH queue. This is based on the idea,
that the AGCH queue has a limited drain rate and that CHANNEL
REQUESTs must be answered within a certain time frame, given
by the minimum value of T3126 (see GSM 04.08). When the AGCH queue
reaches that limit, the last message would be delivered in time if
there were no other delays involved (which is not the case).
The calculation is based on the ratio of the number RACH slots and
CCCH blocks per time:
Lmax = (T + 2*S) / R_RACH * R_CCCH
where
T3126_min = (T + 2*S) / R_RACH
R_RACH is the RACH slot rate (e.g. RACHs per multiframe)
R_CCCH is the CCCH block rate (same time base like R_RACH)
The value depends control_channel_desc.ccch_conf and
rach_control.tx_integer (both from SYSINFO_TYPE_3) and should
therefore by called at least each time after one of these is changed.
For this reason, a signal callback is registered under
SS_GLOBAL/S_NEW_SYSINFO which invokes bts_update_agch_max_queue_length().
Sponsored-by: On-Waves ehf
Based-On: "bts: Calculate length of agch queue" by Ivan Kluchnikov
<kluchnikovi@gmail.com>
This patch adds a common function bts_ccch_copy_msg() that provides
and schedules AGCH and PCH messages. It is basically a frontend to
paging_gen_msg() and bts_agch_dequeue() and contains refactored code
from l1_if.c.
Sponsored-by: On-Waves ehf
Use the lchan->rel_act_kind field for the BCCH activatiob by OML.
The lchan's should be marked as active but no event should be sent to
the BSC. This is mostly like the PCU. We can now remove the secnd
argument from lchan_activate.
Nicolas ended up with linker issues due abis_rsl_sendmsg being
defined twice. Rename our version of the function and update the
code.
Patched with:
@i@
expression E;
@@
- abis_rsl_sendmsg(E)
+ abis_bts_rsl_sendmsg(E)
Currently the LEDs are being accessed directly from within the
l1_if.c file. So the handling of rf mute and activate/deactivate both
access LED_RF_ACTIVE directly. This may lead to an inconsistent LED
status.
This patch replaces these calls to sysmobts_led_set() by an abstract
equivalent bts_update_status(), that uses a set of independant status
ids. The associated values can than be combined into a visible LED
status. Currently LED_RF_ACTIVE is on iff BTS_STATUS_RF_ACTIVE is set
and BTS_STATUS_RF_MUTE is not set.
Sponsored-by: On-Waves ehf
Currently a Change Administrative State Request is just applied
unconditionally to the object's state object and then acknowledged.
This patch implements the special handling of setting the Radio
Carriers state to LOCK or UNLOCK. This is done by passing the
appropriate mute command to the L1 layer. Always all radio channels
are affected, it is not possible to lock single radio channels.
On success, an ACK is sent back to the bsc with the new state (based
on the state passed in the callback by the L1 layer). If something
went wrong or the firmware doesn't support RF mute, a NACK
(REQ_NOT_GRANTED) is sent instead.
Note that a NACK for such a request hasn't been sent by the BTS to
the BSC yet, so (albeit it's spec conformant to do so) the BSC must
be prepared to handle this correctly.
Ticket: OW#976
Sponsored-by: On-Waves ehf
This adds a new function
l1if_mute_rf(femtol1_hdl, ch_mute[8])
to set the mute state for each radio channel. On completion and iff
l1if_mute_rf() returned 0 the callback
oml_mo_rf_lock_chg(mo, ch_mute_state[8], success)
is invoked when the response from the superfemto DSP is received.
Ticket: OW#976
Sponsored-by: On-Waves ehf
The PCU is forcing the activation of a PDCH. Currently the BSC
will receive a channel act ack for a channel that was not
activated at all. Use the "release_reason" flag of the lchan
to see if we have requested a normal activation or a silent
one.
It feels a bit odd to do it in the TX function but it is the
most easy solution right now. I have added logging so it will
not be totally silent.
This introduces a new get_signlink_remote_ip() function whcih we also
use in the RSL code to determine the RTP remote address if the CRCX/MDCX
contains no remote IP address IE.
libosmoabis has a BTS-side implementation of the IPA protocol for years,
and osmo-bts should have used that all the time. Unfortunately it had
its own local hack, this patch is migrating to the libosmocore
implementation.
Instead of calling oml_mo_state_chg() [which transmits OML STATE CHG]
during bts_init(), we use a new oml_mo_state_init() function which
simply sets the state.
During development one switches from GSM900 to GSM1800 and GSM850 to
GSM1900. This commit attempts to make this switch more easy.
GSM1800 and GSM1900 have overlapping ARFCNs. This means that the
mapping from bands to arfcn is not injective. Because of that I
removed the code to deduce the band from the ARFCN. This was done
in commit 8c3d807b3f. The auto-band
option allows to move between GSM900/GSM1800 and GSM850/GSM1900.
Add a simple testcase with these auto-band configurations.
Chapter 5.2 applies to MS procedure, but 5.3 (BSS procedure) defines no
exact criterion, so I decided to use the procedure equivalent to MS.
The criterion is based on a counter S, which is initialized to a preset
RADIO_LINK_TIMEOUT, which can be configured via VTY. Whenever a received
SACCH block is bad, S is counted down by one. If SACCH block is
successfully decoded, S is counted up by two, but never above initial
RADIO_LINK_TIMEOUT value. If S reaches 0, an RSL Connection Failure
Indication with cause RF Radio Link Failure is sent to BSC, which then
aborts channel.
Use link timeout value from BSC via OML attribute.
How to test:
- Set "debug" for "meas" logging.
- Start silent call to an attached mobile.
- Remove battery from mobile or shield mobile.
- Watch S count down.
Issue the RfDeactivate.REQ before sending the MphClose.REQ. Ideally
we would issue MphClose.REQ after the RfDeactivate.CNF but this is
not possible right now.
The current approach makes the following warning of the DSP go away
on shutdown. This was tested with my E71 and an active silent-call
using a SDCCH.
DSP Warning:
[ERROR] : DeviceMng_ValidateL1Handle() => Invalid layer 1 handle
Instead of explicitly having to specify the local IP address for RTP
sockets in the BTS, we just use "0.0.0.0" instead, which gets
translated to INADDR_ANY.
We still accept the configuration directive in old config files, but
when we write, the line will no longer be re-written to the file.
TODO: IMHO, the IPA RSL CRCX/MDCX actually permit the BSC to specify the
IP address on the BTS side, and we probably simply ignore this at this
point.
These attributes are saved in paging_state, we don't need to save them a
second time in struct gsm_bts_role_bts. Add get and set methods for
these attributes and use them consitently in the VTY code.
This was found and debugged by Sylvain. The BTS will always support
A5/0 so we do not keep track of that, the first bit of the flags is
used for A5/1, second for A5/2... but for RSL there is an offset to
go from RSL to A5(x). Add a testcase and change the code.
* Comment out the osmo-bts-bb/Makefile as we have removed it from
the SUBDIRS and are not packaging the code right now
* Add missing include files for the build
Right now osmo-bts requires access to one OpenBSC header file and
this requires that openbsc and osmo-bts git are in the same directory.
Begin with making the location of the OpenBSC sourcecode configurable.
This approach will allow to build osmo-bts on our Jenkins installation
but now has the risk of more code including the openbsc/*.h header files.
This may be adding bells and whistles that nobody wants to touch, but at
least for current analysis/optimiziation they are useful to have. Later
on they should probably be removed again and/or obsoleted by OML
messages for configuration of paging behaviour by the BSC.
We now count the total number of RACH slots, the number with rx level
above the busy threshold, and the number of valid access bursts.
This data is used to generate RSL CCCH LOAD INDICATION for the RACH.
We now implement the fairly complex rules for schedulign of
SI 2bis/2ter/2quater, 13 and 9 on TC=4 and TC=5 of the BCCH Norm.
The patch is currently untested.
Send the RSL ACT ACK/NACK after the Layer1 firmware has acked the
activation/deactivation. In case the channel can not be activated
we will send a NACK. In case the channel can not be deactivated we
will send an ACK and the next time the channel is activated we will
send a NACK. The release ack will be sent once the TxDownlink of the
TCH/SDCCH is closed.
Change the rsl_tx_chan_nack method to create a new msgb to be used
by the hardware layer, change the return value to ask the caller to
delete the msgb.
We now check if the received message is an LAPDm I frame in order to
determine if we have received the first valid encrypted message on the
radio link. This relates to the fact that we often see 'old' UI frames
coming up from L1, even after it has confirmed decryption has been
enabled.
Using osmo-bts-sysmo and this code, it is now possible to do FR and AMR
based voice calls on TCH/F.
A lot of CPU is wasted in the conversion between the RTP formats and the
L1 specific formats for the codec frames. All data needs to be shifted
by four bits, and the order of bits needs to be reversed in every byte.
This only implements creating, binding, connecting and free'ing RTP
sockets, not yet anything regarding receiving or transmitting codec
frames on them.
You will need the rtp branch of libosmocore for libosmotrau
The sequence is as follows:
0) start osmo-bts
1) start connection attempts to BTS
2) issue L1-RESET.req
3) receive L1-RESET.conf
4) issue RF-ACTIVATE.req
5) receive RF-ACTIVATE.conf
6) receive attributes for TRX
7) receive opstart for TRX
8) issue MPH-INIT.req
[...]
The important point here is: We don't want the BSC to set TRX attributes or do
TRX opstart before our RF related hardware is initialized.
* gather measurements from each PH-DATA.ind
* check every TDMA frame about meas period expiration
* compute averages after period expired
* put MS DL MEAS REP into RSL MEAS RES messages, include UL meas
bugs:
* L3 INFO content seems to have some offset
* is_sub is not set anywhere
* measurement periods might have up/downlink offset
This code re-works osmo-bts to add support for the upcoming sysmocom BTS.
It also tries to add some level of abstraction between the generic
part of a BTS (A-bis, RSL, OML, data structures, paging scheduling,
BCCH/AGCH scheduling, etc.) and the actual hardware-specific bits.
The hardware-specific bits are currently only implemented for the sysmocom
femtobts, but should be (re-)added for osmocom-bb, as well as a virtual
BTS for simulation purpose later.
The sysmocom bts specific parts require hardware-specific header files
which are (at least currently) not publicly distributed.
Harald Welte
Max
Pau Espin
Philipp Maier
Neels Hofmeyr