They will gain support to be activated as SDCCH/8 soon too.
Related: OS#5309
Depends: libosmocore.git I56dcfe4d17899630b17f80145c3ced72f1e91e68
Change-Id: Id5b89fe589a52ff88486435ac43809edb4b80f98
If BS Power Parameters IE is present in the channel activation
message, the BTS shall employ dynamic BS power control for that
logical channel and interpret BS Power IE as the maximum value.
If the maximum value is 0 dB, then it does not make sense to send
BS Power Parameters IE to the BTS, because the power control loop
would never exceed the maximum.
Change-Id: If8507992dfd90ade1edda99b72bf2420a702ccd5
Related: SYS#4918, SYS#4919
msg->data_len is the total number of bytes available in the buffer,
not the actual length of the payload. Use msgb_length().
Change-Id: I35bf0827ff14e84a755c1aa24a6efc06bc7b9f9b
Receive and store the Kc128 key from MSC, and use as key sent to BTS if
A5/4 is the chosen encryption algorithm.
(A5/4 in handover will follow in a separate patch)
Related: SYS#5324
Change-Id: I7c458c8a7350f34ff79531b3c891e1b367614469
In build_encr_info(), validate the algorithm and key presence and return
negative if errors are encountered.
At all callers, handle the error case.
An upcoming patch will add handling of Kc128 for A5/4 encryption and
also wants to return error codes. This is a preparation for that patch:
I7c458c8a7350f34ff79531b3c891e1b367614469
Notice that osmo-bsc does send the key along even if A5/0 is chosen,
this patch keeps that behavior unchanged.
Related: SYS#5324
Change-Id: I125d8aabceddd5b34cb98978cee9b6d2fc8fd0f2
Add the Osmocom-specific extension to indicate VAMOS shadow lchans in
RSL, in lchan lookup and RSL message transmission.
Note that RR messages containing cbits (Assignment Command, Handover
Command, ...) must *not* send Osmocom specific cbits to the MS. Only the
RSL messages directed to the BTS send Osmocom specific bits.
Related: SYS#5315 OS#4940
Depends: If33c1695922d110c0d2c60d5c0136caf2587194e (libosmocore)
Change-Id: I957eff0d2c33ec795eda75a4bff21965b0179f73
It's bad to abort the program for an incompatible chan_nr. Instead of
OSMO_ASSERT(), make sure that error handling happens all they way to the
original callers of gsm_lchan2chan_nr etc.
This is also preparation to add further error causes: Osmocom specific
cbits needed for a non-Osmo BTS.
Related: SYS#5315 OS#4940
Change-Id: I71ed6437c403a3f9336e17a94b4948fca295d853
So far there is a bunch of code setting a primary lchan in VAMOS mode.
This patch now adds the actual secondary "shadow" lchans that may be
combined with a primary lchan in VAMOS mode to form a multiplex.
VAMOS lchans are put in the same ts->lchan[] array that keeps the
primary lchans. They are at most two additional usable lchans (for a
TCH/H shadow) added to either TCH/F or TCH/H.
Keeping these in the same array allows looping over all lchans easily.
The ts->max_primary_lchans indicates the index of the first VAMOS shadow
lchan.
Related: SYS#5315 OS#4940
Change-Id: I928af99498bba488d317693f3144d4fccbbe9af3
lchan->activate.info.ch_mode_rate should remain unchanged, it is the
immutable request data. However, for VAMOS, we will want to
automatically see that the chan_mode is chosen correctly.
As a first step, place a mutable ch_mode_rate copy at
lchan->activate.ch_mode_rate, i.e. not in .activate.info, but in
.activate. Use that everywhere.
This is mostly a non-functional change, preparing for a subsequent patch
that adds handling of VAMOS shadow lchans.
As side effect of adding lchan_activate_set_ch_mode_rate_and_mr_config()
after MODE_MODIF_ACK (enabling the voice stream after a channel mode
modify), fix AMR config: the call to lchan_mr_config() was missing.
Change-Id: Icc9cc7481b3984fdca34eef49ea91ad3388c06fe
Put a (primary) lchan in VAMOS speech mode.
This is not yet about activating shadow lchans, this merely puts any
lchan in a VAMOS capable channel- and speech mode.
Protocol:
In RR Channel Mode Modify, send a spec conforming VAMOS channel mode as
well as an Extended TSC Set, wich adds the TSC Set to the training
sequence code value.
In RSL MODE MODIFY, send Osmocom specific extensions to indicate the TSC
Set and TSC, as well as the VAMOS channel mode; only to OsmoBTS type
cells.
- Set the Channel Mode's Channel Rate to Osmocom specific
RSL_CMOD_CRT_OSMO_TCH_VAMOS_Bm / RSL_CMOD_CRT_OSMO_TCH_VAMOS_Lm
- Add the Osmocom specific Training Sequence IE containing both TSC Set
and TSC.
(These are documented in the Abis manual.)
Implementation:
The internal API to request a Mode Modify is lchan_modify(info). Add to
this info the 'vamos' bool, set to true when the modification should put
the lchan in VAMOS channel mode or not.
When info.vamos == true, make sure the channel mode value is a VAMOS
one: in the copy of info->ch_mode_rate at lchan->modify.ch_mode_rate,
convert to the right VAMOS/non-VAMOS equivalent channel mode.
When the modification is through, set lchan->vamos.enabled
appropriately.
This patch also builds on Ic665125255d7354f5499d10dda1dd866ab243d24
'allow explixit TSC Set and TSC on chan activ / modif / assignment'
placing tsc_set and tsc values in the TSC related IEs.
Related: SYS#5315 OS#4940
Change-Id: Ibf53f4797d7491b17a33946fd7d920f038362b4c
An unintended change in default behavior was introduced in patch:
"allow explixit TSC Set and TSC on chan activ / modif / assignment"
Ic665125255d7354f5499d10dda1dd866ab243d24
c33eb8d569
Set tsc_set and tsc = -1 for all lchan_activate_info and
assignment_request requests to actually yield the default behavior of
selecting the TSC based on the timeslot cfg or the BSIC value.
By setting tsc = 0 implicitly, the patch caused all requests to ask for
tsc 0 instead of calling gsm_ts_tsc().
For a Channel Mode Modify in assignment_fsm, pass the lchan's current
TSC to keep it unchanged.
osmo-ttcn3-hacks Id67a949e0f61ec8123976eb8d336f04510c55c01 adds a test
to verify the expected TSC in all of the activation, assignment and
modify messages. Current osmo-bsc master fails, this patch fixes.
Related: SYS#5315 OS#4940 Ic665125255d7354f5499d10dda1dd866ab243d24
Change-Id: If12df11511fe22ea167782f776736a1a9c484b1f
A side effect is that the final cleanup part of that function is now
always called, also when num_cell == 7.
(Whether we should really clear that logging context at that place is a
different question, out of scope here.)
Change-Id: I71a402a0940857bbedbaf25d293429934706a83c
Instead of calling DEBUGPC() over and over, compose a string using
osmo_strbuf and then log it once.
Rationale:
a) DEBUGPC() is a bad idea for gsmtap_log, because each DEBUGPC()
dispatches a separate gsmtap_log packet, fragmenting the actual log line
in wireshark.
b) DEBUGPC() is a bad idea because it checks the logging categories for
every DEBUGPC() invocation.
c) using a separate function with osmo_strbuf and OTC_SELECT, we can
actually skip the entire string composition in case the DMEAS logging
category is disabled, with a single logging category check.
Change-Id: I4cb607ff43a1cb30408427d99d97c103776b6e69
The RSL BS Power IE in measurement reports is encoded as dB / 2.
Instead of using this coding all over the code, converting to dB and
often printing confusing values in logging etc, store as plain dB.
The conversions should be at the points where a "weird" format is
defined: the RSL encoding needs divided-by-two, so apply it there. The
meas_vis is (now unfortunately) defined as div-two, and so on. But
internally we now just store the plain dB value and calculate with it
without duplicating the wire decoding step everywhere.
Rename to bs_power_db to clarify the unit of the stored value.
Change-Id: I229db1d6bcf532af95aff56b2ad18b5ed9d81616
chan_mode_to_rsl_cmod_spd() may actually return negative on error. To be
able to check for that, handle the returned value as a signed rc before
assigning to the unsigned spd_ind.
Related: SYS#5315 OS#4940 CID#236231
Change-Id: I52e13b24ce67e288ff32dbdaa1c1759089926f5c
lchan->modify.info.ch_mode_rate should remain unchanged, it is the
immutable request data. However, for VAMOS, we will want to
automatically see that the chan_mode is chosen correctly.
As a first step, place a mutable ch_mode_rate copy at
lchan->modify.ch_mode_rate, i.e. not in .modify.info, but in
.modify. Use that everywhere.
This is a non-functional change, preparing for a subsequent patch that
adds handling of VAMOS shadow lchans.
Change-Id: I8a3daac0287f15a59d3688388bb13e55facb2cea
Both VAMOS- and non-VAMOS speech modes should result in indentical voice
handling. So make sure that all chan_modes are converted to non-vamos
before comparing / evaluating in switch statements.
Change-Id: I791e7966b1f8eaa3299a8a46abeb313cf5136e0b
So far we have a couple of macros iterating a specific number of lchans,
depending on dynamic timeslot state etc. With addition of VAMOS lchans,
this would become more complex and bloated.
Instead of separate iteration macros for each situation, only have one
that takes a number of lchans as argument. That allows to more clearly
pick the number of lchans, especially for non-trivial VAMOS scenarios.
Related: SYS#5315 OS#4940
Change-Id: Ib2c6baf73a81ba371143ba5adc912aef6f79238d
Activating / modifying to a VAMOS mode will require picking specific TSC
Set / TSC. It is a bad idea to pick the TSC in each message encoding
function, rather make this choice centrally.
So far we pick the training sequence code to use based on the timeslot
configuration, and this TSC is determined only upon encoding the RSL
messages.
Instead, pick the TSC to use upon the initial lchan activation /
modification request; store this in the request structs and pass through
the activation / modification code paths.
For VAMOS modes, we also need to pick a TSC Set. Do so also upon activ /
modif request. Note that the TSC Set is not yet applied in this patch,
it will be applied in upcoming VAMOS patches.
The activ / modif request may pass -1 for tsc_set and/or tsc to indicate
no specific choice of TSC Set and TSC, resulting in the same behavior as
before this patch.
For example, lchan->activate.info.tsc* may be passed as -1. The exact
choice for tsc_set and tsc is then stored in lchan->activate.tsc*, i.e.
one level up (the .info sub-struct is considered as immutable input
args). The lchan->activate.tsc* are the values actually encoded in RSL
messages. After the ACK, the lchan->activate.tsc* is stored in
lchan->tsc* to indicate the TSC actually in use. Same for modif.
Note that in 3GPP TS 45.002, the TSC Set are numbered 1 to 4, while the
TSC are numbered 0 to 7. On the wire, though, TSC Set is sent as 0 to 3
value. This is a weird discrepancy, odd choice made by the spec authors.
For conformance with the spec wording, I decided to pass the TSC Set
number as a 1-4 ranged value, and only convert it to the 0-3 on-the-wire
format upon message encoding. So log messages and VTY output will
indicate the first TSC Set as "1", but the first TSC as "0", as defined
in 3GPP TS 45.002, even if that is somewhat weird.
Related: SYS#5315 OS#4940
Change-Id: Ic665125255d7354f5499d10dda1dd866ab243d24
Expose the training sequence code used in the RSL Channel Description IE
as an input parameter.
So far the Channel Description IE is always composed with a training
sequence code from gsm_ts_tsc(). For RSL commands enabling VAMOS mode,
specific training sequence codes are required.
So far, all callers still use gsm_ts_tsc(), making this a patch without
any functional change. Upcoming patches will pass specific TSC as
configured for VAMOS instead, in specific places.
Related: SYS#5315 OS#4940
Change-Id: I49503a6f5d25bb3bc9a0505bd79ed1d5c4f50577
Prepare for VAMOS, where there will be secondary "shadow" lchans serving
secondary MS on the same timeslots. For those, RSL messages will need to
reflect a different stream ID aka TEI, via an rsl_link_vamos.
Make sure that every code path that sends an RSL message for a specific
lchan selects the RSL link via the new function rsl_chan_link(). When
VAMOS is implemented, this function can select the proper RSL stream.
Rename gsm_bts_trx.rsl_link to rsl_link_primary. This makes sure I'm not
missing any uses of the RSL link, and clarifies the code.
Related: SYS#5315 OS#4940
Change-Id: Ifbf16bb296e91f151d19e15e39f5c953ad77ff17
Firstly, do not store the encoded AMR length-value bits in gsm_lchan->*
before an activation/modify has actually succeeded.
And secondly, do not store the AMR LV structure in struct gsm_lchan at
all, but only generate the TLV exactly when a message is being composed.
In gsm48_multirate_config(), generate the LV directly to a msgb instead
of a static buffer first. gsm0408_test.c expected output verifies that
the generated LV bytes remain unchanged.
In lchan_mr_config(), introduce a target mr_conf argument, so that Chan
Act and Mode Modify may generate the filtered AMR config to different
locations (lchan->{activate,modify}.mr_conf_filtered).
Only after receiving an ACK for Activate/Modify, set
lchan->current_mr_conf from lchan->{activate,modify}.mr_conf_filtered.
Use the properly scoped lchan->activate.mr_conf_filtered for Chan Act,
lchan->modify.mr_conf_filtered for Mode Modify and
new_lchan->current_mr_conf for Handover Command as appropriate.
Related: SYS#5315 OS#4940 OS#3787 OS#3833
Change-Id: Ie57f9d0e3912632903d9740291225bfd1634ed47
The GSM48_CMODE_DATA_* rates are completely unused in OsmoBSC anyway,
but there is some code in abis_rsl.c checking its value, and if we were
to start using it that is the place where it should be.
Related: SYS#5315 OS#4940 OS#3787 OS#3833
Change-Id: Ie0e065a5dca5f4a31d5d81e3528a539214a74170
I noticed during testing that an lchan used as TCH/F in fact still had
its channel mode set to Signalling -- because on Assignment, the Speech
mode used to be placed in the *previous* lchan and the new lchan was
never updated after the Activ ACK. This is unbearable confusion which I
complained about numerous times, so far mostly for cosmetic reasons. But
implementing re-assignment properly actually requires this to be cleaned
up.
Keep all volatile chan mode settings in lchan->activate.* or
lchan->modify.*, and only update lchan->* members when an ACK has been
received for those settings. So a failed request keeps a sane state.
Make sure that those settings are in fact updated in the proper lchan,
upon an ACK, so that subsequent re-assignment or mode-modify know the
accurate lchan state.
Related are upcoming patches that sort out the AMR multirate
configuration in a similar fashion, see
Iebac2dc26412d877e5364f90d6f2ed7a7952351e
Ia7519d2fa9e7f0b61b222d27d077bde4660c40b9
Ie57f9d0e3912632903d9740291225bfd1634ed47.
Related: SYS#5315 OS#4940 OS#3787 OS#3833
Change-Id: Ie0da36124d73efc28a8809b63d7c96e2167fc412
Soon, there will also be enums with ASSIGNMENT_FOR_* and MODIFY_FOR_*
naming. Add the ACTIVATE_ prefix to the existing enum to clarify.
Change-Id: I12190d4d154a1da6a9ebc9a755ccc2fe382ff188
From 3GPP TS 48.008 sec 3.1.30 "Common ID":
"""
If the SCCP connection is established due to CSFB from E-UTRAN and the MSC supports
return to the last used PLMN after CS fallback, then it should send the COMMON ID message
to the BSS including the Last used E-UTRAN PLMN ID information element if available at
the MSC immediately following the successful SCCP connection setup.
"""
Furthermore, 3GPP TS 48.008 version 16.0.0 Release 16 "3.2.1.21 CLEAR COMMAND",
for field CSFB Indication, states:
"""
NOTE: This information element doesn't serve any useful purpose. MSCs should not send the
information element unless it is required by the recipients (due to the need to interwork
with older versions of the protocol). It is expected that in future versions of the present
document, this information element will be deleted from this message.
"""
Hence, build up the EUTRAN neighbor list based on whether we received
the Last E-UTRAN PLMN ID IE during Common Id. In the future, we should
probably filter the list while populating it based on the received IE.
This change will also allow reusing same mechanism for SRVCC
EUTRAN->GERAN support, where te Last E-UTRAN PLMN ID IE can be found
inside "Old BSS to New BSS information" IE in msg HANDOVER REQUEST.
Related: SYS#5337
Change-Id: I5d290ac55eca5adde1c33396422f4c10b83c03d5
It is observed that a CHANnel ReQuireD with access delay
greater than 63 can be received from the Ericsson RBS.
This results in osmo-bsc sending back a CHANnel ACTIVation with
a Timing Advance IE containing the access delay value.
The RBS NACKs this, leading to a BORKEN Channel.
This patch makes the maximum acceptable access delay vty-configurable
and Ignores CHANnel ReQuireD RSL Messages with Access Delay IE greater
than that configured. Default value is 63.
Related: OS#5096
Change-Id: Ie8987bcc0e43921bc753162b77a0efc68799b3ce
On lchan activation, we already know the Timing Advance in most
situations: from the Channel Request RACH, or from a previous lchan in
the same cell. Place this information in lchan->activate.info.ta.
So far, the lchan->last_ta (until recently called rqd_ta) was used to
store the initial TA for channel activation -- move the initial TA to
lchan->activate.info.ta, for proper scoping.
Only an inter-cell handover does not yet know a Timing Advance (until
the Handover Detection RACH is received), so indicate
activate.info.ta_known = false for that case.
If ta_known is false, do not include an Access Delay IE in the Channel
Activation message, ensuring that the BTS does not use an arbitrary TA
that is likely inaccurate.
The effect for OsmoBTS is that we will *not* start the downlink SACCH on
channel activation for inter-cell handover, but will wait for a HO RACH
first, and then use the correct TA when enabling downlink SACCH.
Related: OS#4008 SYS#5192
Change-Id: I986bf93e8acd6aef7eaf63ac962480b680aa894f
Originally, the lchan stored only the Timing Advance from the initial
channel request, hence it was called rqd_ta.
Since quite a while now, rqd_ta also stores the most recent Timing
Advance from each received Measurement Report. So rename to last_ta.
This is cosmetic preparation for an upcoming patch that clarifies
whether the Timing Advance is already known for Channel Activation.
Change-Id: I1049526a173819baeb4978db5bf018ba3f1006a0
If an emergency call arrives at the BSC while all TCH are busy, one TCH
is cleared in favor of the emergency call. However, if emergency calls
are disabled (system information), it is still possible that an MS might
try an emergency call anyway or that due to interference a regular call
might look like an emergency call (channel request reason). In those
cases the preemption must not happen and the emergency call must be
rejected.
Change-Id: I1af1f4fefcbe6a886bb5396901ce0cb2368a0e19
Related: OS#4976
Add bool log argument to lchan_avail_by_type() and omit logging when
passed as false. From handover_decision_2.c, pass 'log' as false, from
all other callers pass true, i.e. for unchanged behavior.
Rationale:
Usually, we use lchan_avail_by_type() to select a new lchan to initiate
actual service. For that, it is interesting to see how osmo-bsc decides
which lchan will be used.
For handover decision 2, we since recently call lchan_avail_by_type()
for each and every handover candidate, to determine whether it will
occupy a dynamic timeslot or not (to know whether we would congest the
other TCH kind). So this happens for each permutation of source lchan
and target cell. That produces a lot of logging, out of proportion of
being useful to the maintainer.
Change-Id: Ia403f8fc853ca9ea9e81f7a7395df6b23845ebed
In order to activate FACCH/SACCH repetition on the BTS, the classmark 3
IE in the CLASSMARK CHANGE message must be parsed and depending on the
Repeated ACCH Capability bit the RSL_IE_OSMO_REP_ACCH_CAP is added to
the RSL CHAN ACT und RSL CHAN MODE MODIFY. Since
RSL_IE_OSMO_REP_ACCH_CAP is a propritary IE, it may only be added for
BTS type osmo-bts.
Change-Id: I39ae439d05562b35b2e47774dc92f8789fea1a57
Related: OS#4796 SYS#5114
The function reduce_rach_dos() only removes the tossed channel requests
from the list, but does not free them.
Change-Id: I0a62fc897c07e118dd637b156b6f2822c44db731
Related: OS#4549
At the moment expired channel requests are dropped silently, however, it
might help to know when this happens - not only for debugging.
Change-Id: Ib49df551a4cd7d5652e85c8ce29ef132385d4ae4
Related: OS#4549
when an emergency call arrives while all TCH are busy, the BSC should
pick an arbitrary (preferably the longest lasting) call / lchan and
release it in favor of the incoming emergancy call.
The release of the existing call is a process that can not be done
synchronously while the ChanRQD is handled sonce multiple messages are
exchanged between BTS and MSC and multiple FSMs need to do their work.
To be able to release one lchan while handling a ChanRQD a queue is
implemented in which the incomming channel requests are collected. If
an emergency call is established while all channels are busy, an
arbitrary lchan is picked and freed. When freeing the lchan is done,
the queue is checked again and the emergency call is put on the free
lchan (TCH/H or TCH/F).
Change-Id: If8651265928797dbda9f528b544931dcfa4a0b36
Related: OS#4549
osmo-nitb supports the modification of an lchan if the lchan is
compatible but in the wrong mode. This feature was dropped in the
transition to AoIP/bsc-split. However, osmo-bsc still has code to
generate and parse the messeages, but the FSMs do not support a mode
modify yetm
Lets add handling for mode-modify to the lchan_fsm and assignment_fsm in
order to support mode modify again
Change-Id: I2c5a283b1ee33745cc1fcfcc09a0f9382224e2eb
Related: OS#4549
Currently osmo-bsc encodes the IAR Rest Octets as follows:
IAR Rest Octets
0... .... = Extended RA: Not Present
.0.. .... = Extended RA: Not Present
..1. .... = Extended RA: Present
...0 1011 = Extended_RA: 11
0... .... = Extended RA: Not Present
.L.. .... = Additions in Rel-13: Not Present
Padding Bits: default padding
This is not really critical, but still may look confusing as this
is only relevant for the PS domain (11-bit RA), while osmo-bsc is
responding to a CHANNEL REQUEST in the CS domain.
Change-Id: I30a43efc70345a4bb0571127c239a24422b7fd2c
Neels Hofmeyr
Pau Espin
Vadim Yanitskiy
Keith Whyte
Philipp Maier