Commit Graph

589 Commits

Author SHA1 Message Date
Neels Hofmeyr a0fb37906d rename RSL_ENC_ALG_A5 to ALG_A5_NR_TO_RSL, clarify
The naming confused me so that I wrote buggy code again. Hopefully this
clarifies which representations the code paths are using.

In the macro code, highlight the error case of n <= -1 explicitly.

Also add ALG_A5_NR_TO_PERM_ALG_BITS. I need the 1<<n case in an
upcoming patch.

Related: SYS#5839
Change-Id: I7557ae97764bba09c906748a18e9031dfb362611
2022-02-18 13:21:56 +01:00
Neels Hofmeyr f8345b7ad5 fix two comments in chan_counts.h
An earlier patch version had that typedef, the merged version switched
to the struct containing the array.

Change-Id: Id8ca7b298436feb98f4a563ad3cdea510b9362b0
2022-01-21 16:53:35 +01:00
Pau Espin 326ee2ea49 Fix DLCI CC bits transmitted in SAPI "n" REJECT
The SAPI "n" REJECT messages were being sent with DLCI keeping the RSL
LINK ID format, which is not the same for CC bits.

With this patch, TTCN3 test BSC_Tests.TC_rll_sapi_n_reject_dlci_cc
passes again.

Related: OS#4728
Related: SYS#5047

Change-Id: Icc187f594743040a3d9b8beff7d9cfc21dd6eb08
2022-01-13 06:08:02 +00:00
Neels Hofmeyr c984dc1a86 fix gscon clear 1/n: store clear cause in gscon
Allow returning a context sensitive cause instead of a hardcoded one in
gscon pre_term().

Also, the conn->cause is needed to move message dispatch to an "onenter"
function in patch I234b2a754d0c98031056981823cdbc187e977741. I Split
this part off as a separate patch for better readability.

Related: OS#5337
Change-Id: Ib6432746040899129d1d73ae8dc59add2d88a915
2022-01-04 13:33:26 +00:00
Philipp Maier 3ba9bd7c35 abis_nm: actively block BTSs with invalid configuration
At the moment the BTS configuration is checked, but the check does not
have much consequence other than that some initialization that is not
executed. The BTS will go into the OML bootstrap phase anyway and most
likely fail at some later point due to the invalid configuration. To
reduce noise and unexpected behaviour of the BTS lets make sure that the
OML boostrap phase can only proceed when the BSC conciders the
configuration as valid.

Change-Id: I42c1c26a9b800600787b1266a871f95f2114c26e
Related: SYS#5369
2021-12-13 18:03:12 +01:00
Oliver Smith 2df65db3da stats: add bsc.paging:expired
Similar to paging:attempted, count paging:expired not only per BTS, but
also for the whole BSC. Add active_paging_requests to struct bsc_subscr,
to increase the counter only once if paging expires, and not once per
BTS where paging expired.

Related: SYS#4878
Change-Id: I9c118e7e3d61ed8c9f1951111255b196905eba4d
2021-11-29 11:33:34 +01:00
Neels Hofmeyr d13ef633d2 move time_cc to libosmocore osmo_time_cc
Related: SYS#4878
Depends: Iabb17a08e6e1a86f168cdb008fba05ecd4776bdd (libosmocore)
Change-Id: Ica9f908a1a30f334a24c59471affa11225117e12
2021-11-16 12:06:53 +01:00
Vadim Yanitskiy 335361fbeb [overpower] Allow configuring specific channel mode(s)
Change-Id: I34d29d7d0f66c629367f3d6e8a660e199ecbe080
Related: SYS#5319
2021-11-15 11:59:03 +00:00
Vadim Yanitskiy f59abedb24 struct gsm_bts: s/temporary_overpower/top_acch_cap/g
Let's have a short and consistent naming for both ACCH repetition
and temporary ACCH overpower structures, like it's done in osmo-bts.

Change-Id: I39b98dcd14219402959646524315d5afea7c08cf
Related: Ib1d51f91139b4c2fe794e37fc8543b2d7a9b9c07
2021-11-15 11:59:03 +00:00
Vadim Yanitskiy c8bd1eeaca struct gsm_bts: s/repeated_acch_policy/rep_acch_cap/g
Let's have a short and consistent naming for both ACCH repetition
and temporary ACCH overpower structures, like it's done in osmo-bts.

Change-Id: Ia12c83ad1af4744ce28ba655ac806784f746e88a
Related: Ib1d51f91139b4c2fe794e37fc8543b2d7a9b9c07
2021-11-15 11:59:03 +00:00
Vadim Yanitskiy ff1328a038 struct gsm_bts: simplify comments for ACCH repetition/overpower
Change-Id: I75b0e289c47841aea22b5966487535cbe855c84f
2021-11-15 11:59:03 +00:00
Neels Hofmeyr a249babf20 implement bts.N.cm_serv_rej:<cause> rate counters
Related: I0214b27da18af87eca9715ebf7eeeff945e3e12a (osmo-ttcn3-hacks)
Related: SYS#4878
Change-Id: I79b1261e5a281d9797eaaf9c27d90edd8e27c78b
2021-11-10 17:53:44 +00:00
Neels Hofmeyr aa09938d2c implement all_allocated:{static_sdcch,static_tch} rate counters
Same as all_allocated:{sdcch,tch}, but already trigger when all
non-dynamic timeslots are allocated.

Related: SYS#4878
Related: Ib3997a827c9cc43d1361bb0cf3bfab9f6d91bf82 (osmo-ttcn3-hacks)
Change-Id: I2fa14531f16d3f07085620f1c50eb839c420da6a
2021-11-10 13:27:43 +00:00
Neels Hofmeyr 41f143827d implement all_allocated:{sdcch,tch} rate counters
Based on allAvailable{SDCCH,TCH}Allocated performance indicators, see
3GPP TS 52.402.

Related: SYS#4878
Related: Ib3997a827c9cc43d1361bb0cf3bfab9f6d91bf82 (osmo-ttcn3-hacks)
Change-Id: I8b06e435a224c8708cd6c67e97ee5413718fc1ed
2021-11-10 13:27:43 +00:00
Neels Hofmeyr e0458c2e00 add time_cc API: cumlative counter for time, reported as rate_ctr
This is a candidate for adding to libosmocore (as osmo_time_cc), but
let's first use this in osmo-bsc to make sure that it works as intended.

I started out expecting to be done with this in half an hour, but I
found out that accumulating elapsed time to an integer counter has a
staggering amount of complexity to it, and a million pitfalls.

The intended use is to report allAvailableSDCCHAllocated and
allAvailableTCHAllocated performance indicators in OsmoBSC. Hopefully
this will also be generally useful elsewhere, to be worth the effort.

Related: SYS#4878
Change-Id: Icdd36f27cb54b2e1b940c9e6404ba9dd3692a310
2021-11-10 13:27:43 +00:00
Neels Hofmeyr e455f0ab02 refactor lchan counting
Add chan_counts_for_trx() and chan_counts_for_bts(). Drop
bts_count_free_ts() and trx_count_free_ts().

Rationale:

The bts_count_free_ts() and trx_count_free_ts() always returned the
number of free lchans, not timeslots. Hence, passing the pchan type as
argument never really matched the semantics.

Especially, when looking for free SDCCH, there is no clear match on a
gsm_phys_chan_config enum value: SDCCH8_SACCH8C, CCCH_SDCCH4,
CCCH_SDCCH4_CBCH, SDCCH8_SACCH8C_CBCH? -- GSM_LCHAN_SDCCH is clear.

==> Rather count free lchans by enum gsm_chan_t.

Counting lchans of distinct types required separate iterations for each
lchan type.

==> Rather compose an array of counts for all types, in one go.

I need to count the amount of free SDCCH lchans in an upcoming patch to
implement the performance indicator allAvailableAllocatedSDCCH (cumulate
time for which no SDCCH are available).

To implement allAvailableAllocated{SDCCH,TCH}, I need a count of both
the used as well as the total lchans for a type: it does not make sense
to flag "all available allocated" if none are ever available.

To properly count dynamic ts, I need the maximum total that can be
possible at any time. And to count currently free lchans, I need the
current total. This may seem counter intuitive, but consider, e.g.:

- Obviously, if a cell has only static TCH/F timeslots, it does not make
  sense to flag that all available TCH/H are occupied, because no TCH/H
  are available ever. Just stating this as contrast to dyn TS.

- If a cell has OSMO_DYN timeslots, I *do* want to flag that all TCH/H
  are occupied when all dyn timeslots are fully occupied.

- If those OSMO_DYN however are all used as TCH/F, the current total of
  TCH/H becomes zero, and it seems like TCH/H should not be considered.

- To count the nr of currently free lchans, I need the currently
  possible total of lchans and the nr of occupied lchans.

So return both a maximum total and a current total of lchans. In above
example, the maximum total shows that there would be TCH/H possible.

BTW, it would be nice to keep a chan_counts array on trx, bts and bsc
level and update as channels are allocated and released, instead of
counting them all over periodically. But it's less error prone this way.

Related: SYS#4878
Change-Id: I2fb48c549186db812b1e9d6b735a92e80f27b8d3
2021-11-10 13:27:43 +00:00
Neels Hofmeyr d5a6dca2f9 implement incoming_intra_bsc_ho:* rate counters
We have lots of counters for intra-BSC handover *away from* a given BTS,
but still missing are counters indicating how many handovers *targeted*
a given BTS. Also count incoming HO.

Related: SYS#4878
Related: Iba229313d73fa20266f6d4eac5820579fb14c604 (osmo-ttcn3-hacks)
Change-Id: Id9f2c6e2865ebe680879018fff08d283ce24c983
2021-11-06 17:02:38 +01:00
Neels Hofmeyr 8700803fa8 for linter: s/while(0)/while (0)
Change-Id: Ib422e7d1a7d543dcd8738581839ce55bb8fc29d2
2021-11-06 17:01:58 +01:00
Neels Hofmeyr 0887442c20 drop unused gsm48_tx_mm_serv_ack()
Related: SYS#4878
Change-Id: Ia9d841a8243adca347e7ea79d31e3cd65eab27ea
2021-11-05 12:01:27 +01:00
Neels Hofmeyr 96887554f9 add chreq:successful_<reason> rate counters
Related: SYS#4878
Change-Id: I32c2c197a6199617a82986480b686c515fa40d62
2021-11-05 12:01:27 +01:00
Philipp Maier 085a92584f heighbor_ident: add/del neighbor cells via ctrl interface
The VTY allows flexible control over the neighbor cell information via
the neighbor command, which can be found in the configure terminal under
the bts node. Lets add pendant of this command on the control interface
as well.

Change-Id: I343a40e18fa9b91e6c381912c0426a002841e079
Related: SYS#5641
2021-11-03 17:25:28 +00:00
Neels Hofmeyr 33d48cd42b constify lchan_state_is()
An upcoming patch would rather pass a const struct gsm_lchan*.
See I2fb48c549186db812b1e9d6b735a92e80f27b8d3.

Related: OS#4878
Change-Id: I523cbf04e77f43924c3f09094d56f815d3de640d
2021-11-01 11:22:48 +00:00
Neels Hofmeyr 065ff875e9 stat: add bts.N.num_trx:rsl_connected
Controversy: this duplicates bts.N.rsl_connected. I would like to add
this duplication for consistency, since we now have these counters:

  bsc.0.num_trx:rsl_connected
  bsc.0.num_trx:total
  bts.N.num_trx:total

and the old

  bts.N.rsl_connected

which does not fit well with above naming scheme. Any user will be
justified to expect a stat named bts.N.num_trx:rsl_connected as well.

Determine bts.N.num_trx:rsl_connected in the new function
bsc_update_connection_stats(), where the other num_trx:* are set.

Related: SYS#5542
Related: I5be1cb470930354c4561cbed301bc50a32484ed9 (osmo-ttcn3-hacks)
Depends: I137992a5479fc39bbceb6c6c2af9c227bd33b39b (libosmocore)
Change-Id: I55b55159fe13d937e441d8c2ed915734463e1154
2021-10-12 16:08:09 +00:00
Neels Hofmeyr 5f1317ba91 stat: add bts.N.num_trx:total
This is similar to bsc.0.num_trx:total but per single BTS.

Related: SYS#5542
Related: I5be1cb470930354c4561cbed301bc50a32484ed9 (osmo-ttcn3-hacks)
Depends: I137992a5479fc39bbceb6c6c2af9c227bd33b39b (libosmocore)
Change-Id: I283d38e7a8c032e274a5bd2fa150ec2c9a7157b4
2021-10-12 16:08:09 +00:00
Pau Espin 40c7410f9e Move ts_fsm_init to static constructor [3/4]
This allows having it initialized automatically, as we usually do with
this type of code. As a result, tests or other apps importing libbsc
don't need to take care of calling it.

NOTE: This fix is required by follow-up patches where some stubs are removed
and hence some tests start using FSMs internally. Since tests were not
using those FSMs before, there was no need to call ts_fsm_init().

This is one further step towards fixing interdependency mess of symbols
and stubs.

Change-Id: I0e4b95b5e73fbb3844d83ba33e66786831088e1f
2021-10-07 14:08:22 +02:00
Pau Espin 7974008436 bts_trx: Fix timeslot_fsm not properly freed during trx free() [1/4]
osmo_fsm_inst_free() must be called explicitly, otherwise the instance
is kept in the llist of instances and produces heap-use-after-free.

Note: This fix is required by follow-up patches where some stubs are removed
and hence some tests start using FSMs internally. Due to this bug, tests
will crash due to reason explain in previous paragraph.

This patch itself may introduced failures to build due to some new
interdependencies being introduced in same follow-up patches mentioned
above, which are in turn fixed by this present patch.
So they are expected to be merged together.

Change-Id: Ib0e5560efe518833f76f846d7269e82d85c186a1
2021-10-07 14:07:52 +02:00
Pau Espin d203d173f2 MS Power Control Loop: Use P_CON_INTERVAL=2 by default
Increase the reaction time at the expense of more stable loop with less
temporary oscillations.

See updated user manual documentation in this commit for a larger
description.

Related: SYS#5371
Change-Id: I46be244a5e01a74086e3a977ec3ea139742a0074
2021-10-07 10:44:44 +00:00
Neels Hofmeyr 9f14174440 drop obsolete comment
Change-Id: I7cc79e368512483ff4e1e56b49ad2b950f627c2f
2021-10-05 08:29:15 +02:00
Keith Whyte 2262245209 Implement MS Uplink Power Control Loop
* Adds vty option dyn-bsc for ms-power-control -> mode
* Imports power_control.c from osmo-bts project
  [at commit 2f3cd4b697972d8484f9a9d3b7ef634086f65fa5]
* Removes unused C/I code from osmo-bts's power_control.c

This patch then calls the power loop on receipt of measurement
reports and updates the MS Power Level accordingly.

Change-Id: Ibc307e758697eb5ca3fb86622f35709d6077db9e
2021-10-05 04:32:33 +00:00
Neels Hofmeyr 62c4097dcf fix TSC / TSC Set used for Handover
From the nature of the lchan_activate_info.tsc_set and .tsc, it is easy
to forget to set tsc_set,tsc = -1 to use default TSC Set and TSC values.
Handover code is one such instance that forgets to set -1.

Change the semantics of tsc_set and tsc so that this kind of error can
not happen again as easily: use a separate bool to flag whether to use
the default config or explicit values.

Implicitly fix the lchan_activate_infos "launched" in handover_fsm.c as
well as abis_rsl_chan_rqd_queue_poll().

Related: OS#5244 SYS#4895
Related: I1ed6f068c85b01e5a2d7b5f2651498a1521f89af (osmo-ttcn3-hacks)
Change-Id: Iae20df4387c3d75752301bd5daeeea7508966393
2021-10-04 11:04:21 +00:00
Pau Espin 37288e34c1 cosmetic: fix comment typos in signal.h
Change-Id: Ie0c0c75a62b460887f2c78efe043b9e11a76919e
2021-09-29 19:02:12 +02:00
Pau Espin 464227d071 MS Power Control Loop: Allow Turn off/on C/I independent from value setting
Improve the current VTY support to allow enabling/disabling C/I logic
independent from value setting. This way C/I support can be quickly
disabled & enabled.

Reminder: changing power parameters still require VTY Command "bts NR
resend-power-control-defaults" to be excuted prior to new parameters
being applied on the BTS.

Related: SYS#4917
Change-Id: Id1224c2d9a52db2ed805c49e048d3086ed0167f5
2021-09-29 15:39:17 +02:00
Neels Hofmeyr 0559bd9775 add CTRL 'rf_states' and 'bts.N.rf_states'
These commands return a listing of OML state, RF policy as well as RSL
connection status for each TRX in the form:

 <bts_nr>,<trx_nr>,<opstate>,<adminstate>,<rf_policy>,<rsl_status>;<bts_nr>,<trx_nr>,...

For example, the root node 'rf_states' may return:

 0,0,operational,unlocked,on,rsl-up;1,0,operational,unlocked,on,rsl-down;2,0,inoperational,locked,on,rsl-down;

A 'bts.N.rf_states' returns the same form of string, but lists only the
TRX for the given BTS nr.

Note, there is already a CTRL command 'bts.N.rf_state' (singular
'rf_state', not plural 'rf_states'), which only reflects the overall
status of all TRX combined. This new command has per-TRX resolution.

The rf-policy is so far always looked up in the global gsm_network flag,
as does the old 'rf_state' command; see osmo_bsc_rf_get_policy_by_bts()
which does not depend on the specific BTS at all. This may be worth
revisiting in the future, so I am already including the rf-policy in the
rf_state string for each TRX, even though it is globally identical.

Related: SYS#5542
Related: I01e6f391a5e71b0606c42be9b57f8a1687d59bcb (osmo-ttcn3-hacks)
Change-Id: I14fa2678fc8f2c11a879c5e9615ac552782c5b7e
2021-09-14 08:44:45 +00:00
Pau Espin 506aa70d77 Support Neighbor Address Resolution over PCUIF IPA multiplex
While NACC was initially developed, it became clear there was need for
a way to interact PCU<->BSC in order resolve ARFCN+BSIC into CGI-PS
for later RIM usage.
Hence, this resolution was first (until today) implemented using an out
of bands RPC system using the CTRL interface, which required specific
config to be written and matches in osmo-pcu and osmo-bsc VTY (ip+port
of the CTRL interface to use).
However, this has several shortcomings:
* As explained above, specific configuration is required
* Since recently, we do support BSC redundancy in osmo-bts. Hence the BTS
  may switch to a BSC other than first one. If that happened, that'd mean
  the CTRL interface would still point to the initially configured one,
  which may not be the same currently serving the PCU.

During recent development of ANR related features, a similar need for
PCU<->BSC was required, but this time it was decided to extend the IPA
multiplex of the Abis OML connection to pass PCUIF messages,
transparently forwarded to each side by the BTS.
This has the advantage that connection PCU<->BTS is handled by BTS and
both sides send messages transparently.

Let's switch by default to using this new interface, while still
maintaing the old way for a while (announcing them as deprecated) to
avoid breaking existing deployments until they are upgraded to new
versions of osmo-pcu and osmo-bsc.

Change-Id: I9073a121564503f483c84263ac72476041e47c03
Related: SYS#4971
2021-09-13 16:04:05 +02:00
Pau Espin 54283ba626 MS Power Control Loop: Support set up of C/I parameters for osmo-bts
This commit extends existing VTY and RSL infrastructure to configure and
manage MS Power Parameters used in MS Power Control loop, by adding
support to set up Carrier-to-Interference (CI) parameters.

Using C/I instead of existing RxQual is preferred due to extended
granularity of C/I (bigger range than RxQual's 0-7).
Furthermore, existing literature (such as "GSM/EDGE: Evolution and Performance"
Table 10.3) provides detailed information about expected target values,
even different values for different channel types. Hence, it was decided
to support setting different MS Power Parameters for different channel
types.

These MS Power Parameters are Osmocom specific, ie. supported only by
newish versions of osmo-bts. Older versions of osmo-bts should ignore
the new IEs added just fine. The new IEs containing the MS POwer
Parameters are not send for non osmo-bts BTSs, hence this commit is
secure with regards to running  osmo-bsc against an ip.access BTS such
as nanoBTS.

Related: SYS#4917
Depends: libosmocore.git Change-Id Iffef0611430ad6c90606149c398d80158633bbca
Change-Id: I7e76ec47b323d469f777624b74b08752d1f5584f
2021-09-06 12:07:20 +02:00
Neels Hofmeyr 08de290aa8 add stat_items for BTS and TRX connection stati
So far we have stat items per BTS. Add stat items summing overall BTS
status.

Add stat items:
- num_bts:oml_connected
- num_bts:all_trx_rsl_connected
- num_bts:total
- num_trx:rsl_connected
- num_trx:total

Related: SYS#5542
Related: Ic1b35b7406547f92818afe399a2383d154576409 (osmo-ttcn3-hacks)
Change-Id: I2057a798e681a169cc03243a09b3d6449734c010
2021-09-05 16:24:18 +02:00
Philipp Maier 8d22e68706 osmo_bsc_main: integrate MGW pooling into osmo-bsc
Since the libosmo-mgcp-client now supports MGW pooling, lets use this
feature in osmo-bsc. Large RAN installations may benefit from
distributing the RTP voice stream load on multiple media gateways.

Depends: osmo-mgw Icaaba0e470e916eefddfee750b83f5f65291a6b0
Change-Id: I8f33ab2cea04b545c403a6fe479aa963a0fc0d0d
Related: SYS#5091
2021-09-03 15:03:38 +00:00
Philipp Maier 034cc1216a bty_vty: add VTY settungs for temporary overpower
To configure temporary overpower, new VTY commands are added. This patch
also addes the logic needed to attach the temporary overpower IE to the
RSL CHANNEL ACTIVATE message.

Change-Id: I488a91bb4ed86f630db56564a0cd293f39f0f690
Related: SYS#5319
2021-09-02 17:44:54 +00:00
Neels Hofmeyr a268523e3d add stat items bsc.0.num_msc:connected, .num_msc:total
We already have MSC connection stat items, but for hysterical raisins
there are separate such stats for each MSC. Hence we have N connection
counters, each being either 0 or 1, for a single MSC.

Add a new stat counting the *overall* MSCs that are connected,
and one indicating the total number of configured MSCs.

Related: SYS#5542
Related: I178dcf4516606aa561d47b06061b8a416d3c40cf (osmo-ttcn3-hacks)
Change-Id: If76bbf9b3adb64c68d5c31c6b526fa71a99996ae
2021-08-30 18:21:50 +02:00
Neels Hofmeyr a5d3c9d0f2 move BSC level stats and rate counters to new bsc_stats.[hc]
Instead of having static const structs in header files (which end up
duplicated in each and every compile unit!), have one .c file with the
rate_ctr and stat_item descriptions.

Related: SYS#5542
Change-Id: I8fd6380b5ae8ed2d3347e7cfbf674c30b6841ed9
2021-08-30 16:18:52 +00:00
Neels Hofmeyr f8bed50e05 vty: add "msc N bssmap reset" command
Allow resetting the BSSMAP link from VTY, for BSC_Tests.ttcn.

In the field, detecting that an MSC is lost is done by getting three
connection failures in a row. For the BSC_Tests, it is easier to just
provide a VTY command to reset an MSC's link status.

I want to add tests that verify the stat items reflecting the MSC
connection status. To be able to run a test expecting fewer connected
MSC after a test that launched more MSCs requires the links to be reset.

Related: SYS#5542
Related: Ice3056dc46c94f9399f8379db7aeb7193782f2f2 (osmo-ttcn3-hacks)
Change-Id: I1975941b790d2b30d0904d41e456220cba26ecff
2021-08-30 16:18:12 +00:00
Neels Hofmeyr c746509d3c early IMM ASS 3/n: implement 'pre-ts-ack'
Add experimental 'pre-ts-ack' to the 'immediate-assignment' options:
send the IMM ASS even before a dynamic timeslot is switched. This
possibly saves an Abis roundtrip, but may be racy.

When pre-ts-ack is chosen, already do the IMM ASS before the dyn TS
pchan switch is ACKed.

In Immediate Assignment, in case the dyn TS is not ready yet, get the
pchan kind from lchan->type, which already reflects the target type, and
not from ts->pchan_is, which still reflects the previous pchan type.

Related test is in I2ae28cd92910d4bc341a88571599347a64a18fe5

Related: SYS#5559
Change-Id: I19e6a3d614aa5ae24d64eed96caf53e6f0e8bb74
2021-08-16 02:13:17 +02:00
Neels Hofmeyr eec43fa532 early IMM ASS 2/n: implement 'pre-chan-ack'
When 'immediate-assignment pre-chan-ack' is set, send the Immediate
Assignment directly after the Channel Activation, not waiting for the
Activation ACK, to save an Abis roundtrip.

Related test is in If71f4562d532b6c5faf55f5fd073449a8a137ebf

Related: SYS#5559
Change-Id: I56c25cde152040fb66bdba44399bd37671ae3df2
2021-08-16 02:13:17 +02:00
Neels Hofmeyr 225af37f48 early IMM ASS 1/n: add vty config option
This patch adds only the VTY config option without any effect, to ease
patch review.
The implementation follows in I56c25cde152040fb66bdba44399bd37671ae3df2

The new config option is written so that further variants of Immediate
Assignment sequencing may be added easily.
See also I19e6a3d614aa5ae24d64eed96caf53e6f0e8bb74.

Related: SYS#5559
Change-Id: I710343d1728153faf3db9758ff5a1ef26bb8d3d4
2021-08-16 02:13:17 +02:00
Neels Hofmeyr 57af76cdcf introduce gsm48_lchan_and_pchan2chan_desc()
The function gsm48_lchan2chan_desc_as_configured() dups
gsm48_lchan2chan_desc() with merely a different pchan type
(ts->pchan_from_config instead of ts->pchan_is).

In an upcoming patch, I would like to do the same, just with yet another
pchan value (derived from lchan->type, because that reflects the channel
type even before a dynamic timeslot switched its pchan type).

So replace gsm48_lchan2chan_desc_as_configured() by
gsm48_lchan_and_pchan2chan_desc() with explicit pchan arg;
also call this from gsm48_lchan2chan_desc(), reducing code dup.

gsm48_lchan2chan_desc_as_configured() had more concise error logging.
Absorb that into the new gsm48_lchan_and_pchan2chan_desc().

Add gsm_lchan_and_pchan2chan_nr(), like gsm_lchan2chan_nr() just with
explicit pchan arg, to be able to pass the pchan down from the new
functions mentioned above.

Related: SYS#5559
Change-Id: I67f178c8160cdda1f2ab5513ac4f65c027d4012f
2021-08-16 00:12:12 +00:00
Pau Espin 56eda35874 Introduce VTY option to forbid use of TCH for non-voicecall signalling
Usual allocation mechansim, when some signalling channel is needed,
first tries to reserve an SDCCH, and if all of them are exhausted, then
attempts to reserve a TCH as a last resort.
This, however, may cause TCH starvation under certain situations, for
instance if there high load on other services (LU, SMS, etc.).
Hence, it may be desirable for the operator to forbid reservation
of TCH slots once SDCCH become exhausted. This commit is thus adding a
VTY command which allows forbidding it. The default behavior (allow using
TCH timeslots when SDCCHs are exhausted) is kept as before.

The above mentioned prohibition is applied only to non-voicecall related
signalling services. That's because voicecall services will end up
requiring a TCH anyway, and forbidding reservation of TCH straighaway
when SDCCHs are exhausted would mean no voice calls could be initiated
while still TCHs would be available.

Related: SYS#5548
Change-Id: Ib08027125145df26602069bfb51847063b0ccc0c
2021-07-23 13:36:03 +02:00
Pau Espin c8edaad0bf Split bts_vty.c creating bts_trx_vty.c
Change-Id: I15ec8f71a5d31915162cb3ad75ea77e934fa4887
2021-07-23 13:35:04 +02:00
Pau Espin e19289fb89 Split bsc_vty.c creating bts_vty.c
Change-Id: I347e7da328fed0733af2eec10a3ca6e02a148308
2021-07-22 17:26:56 +00:00
Daniel Willmann b2b47d2c47 bts: Clear BTS_STAT_CHAN_*_{TOTAL,USED} on bts disconnect
Adds gsm_bts_stats_reset() to clear the stats and calls it from the
different models.

Change-Id: Ic42687cd73e3546edaa99fb1268a5960ffa43b12
Related: SYS#5541
2021-07-22 15:45:24 +00:00
Pau Espin 2956b52c5b Add new lchan_select_set_type() API helper
It's an easy helper, but it helps in standarizing and finding similar
places in code.
Morevoer, it will be used in follow-up commit where we first use
lchan_avail_by_type and finally we select it in a later stage.

Change-Id: I025a40962a5e5d40543b297a0760e47618fb525c
2021-07-20 10:07:03 +00:00
Philipp Maier 181b5f3b9a handover_ctrl: add control interface for handover settings
The VTY handover_vtc.c offers a large number of handover specific
settings. Those settings are (with one exception) auto generated using
macros. Lets add an equivalent for the control interface that uses the
same auto generation mechanisms.

Change-Id: I12f143906818fd6b16e8783157cbb1eb51e49ffc
Depends: libosmocore I53fc207677f52b1dc748b01d58424839cdba807c
Related: SYS#5369
2021-07-19 10:44:05 +02:00
Neels Hofmeyr ae0b737c62 separate 'interference-meas level-bounds' cfg and used
The VTY defun already indicates BSC_VTY_ATTR_RESTART_ABIS_OML_LINK
correctly, but so far we would immediately start using the new values
internally, and wrongly interpret interference levels. Fix that.

Have bts->interf_meas_params twice: interf_meas_params_cfg for the VTY
configured values, and interf_meas_params_used for the values that the
BTS actually knows about, after they were sent via OML.

In a running BSC, when changing the interference level boundaries on the
telnet VTY, the BTS is not immediately told about the change. That would
require a BTS restart. Hence store the cfg values separately in
interf_meas_params_cfg. For comparing/printing interference levels in a
running BTS, only employ the values that were actually sent via OML and
placed in interf_meas_params_used.

Related: SYS#5313
Change-Id: Iad8cf4151ff7f86dc0549158ed5d91d788d40b1f
2021-07-16 16:04:18 +00:00
Neels Hofmeyr be32e93513 hodec2: add low-rxqual-assignment penalty timer (2/2)
Hold off re-assignment after an intra-cell re-assignment due to low
rxqual.

Adjust test_amr_tch_h_to_f_rxqual.ho_vty to show the changed behaviour.

Related: SYS#5198
Change-Id: Id00a07313fe04eec509b336c0637b59c707760e0
2021-07-15 09:28:18 +00:00
Neels Hofmeyr 71526043ea ensure trigger_ho() returns zero only when HO or AS was indeed triggered
In an upcoming patch, handover_decision_2.c will use this indicator to
decide whether to start a penalty timer:
"hodec2: add low-rxqual-assignment penalty timer (2/2)"
Id00a07313fe04eec509b336c0637b59c707760e0

Related: SYS#5198
Change-Id: I5de385e0666f716184a62e6e70d656545ac5d2ee
2021-07-15 09:28:18 +00:00
Neels Hofmeyr c8cd61ddf2 RES IND: add VTY: bts / channel allocator avoid-interference (0|1)
Store the config option whether the channel allocator should try to
avoid lchans with higher interference levels reported in RES IND.

The actual implementation of avoiding interference follows in
I844494092193811dfd9fa4d52983cbaed0fc9248

Related: SYS#5313
Change-Id: I8b62d0b41ad9e908b27713db9219e3dbc1ebaab7
2021-07-11 20:31:41 +02:00
Neels Hofmeyr e5a761c6b8 RES IND: parse msg and store interference levels in lchans
Also show the current interference levels of unused lchans in the vty.

Related: SYS#5313
Change-Id: Iccc1391e8419604bb09e464db8455e053dfbc982
2021-07-11 20:28:02 +02:00
Neels Hofmeyr 9d4865ecae hodec2: [2/2] implement automatic choice between FULL and SUBSET measurements
Add TDMA_MEAS_SET_AUTO to indicate automatic choice between FULL and
SUBSET measurements depending on DTX. So far use only in hodec2.

TDMA_MEAS_SET_AUTO looks at each individual measurement report's DTX
flag and for each report chooses FULL if DTX is not used, or SUB if DTX
is used.

The default setting for 'handover2 tdma-measurement' is still 'subset'.
To use the automatic choice, users need configure
  handover2 tdma-measurement auto

Change-Id: I67dce55ccf892c8679272ee5dfedc25620f0f725
2021-07-09 11:51:40 +00:00
Neels Hofmeyr 7225fe4902 hodec2: [1/2] implement automatic choice between FULL and SUBSET measurements
Cosmetic preparation for enabling automatic choice between FULL and
SUBSET measurements depending on DTX in handover decision 2.

Change the internal API to pass separate enums for the choices {RXLEV,
RXQUAL}, {UL, DL} and {FULL, SUB}.

Change-Id: I283e03126a6bc1f5f1b35f9801e841053edd2947
2021-07-09 11:51:40 +00:00
Pau Espin cc75145131 Rename osmo dyn ts enums to contain SDCCH8
They will gain support to be activated as SDCCH/8 soon too.

Related: OS#5309
Depends: libosmocore.git I56dcfe4d17899630b17f80145c3ced72f1e91e68
Change-Id: Id5b89fe589a52ff88486435ac43809edb4b80f98
2021-07-06 07:16:15 +00:00
Vadim Yanitskiy 997a257f8d power_control: constrain BS power reduction on BCCH carrier
BS Power Control is not allowed on the BCCH/CCCH carrier, unless
the BTS is operating in the BCCH carrier power reduction mode.

Allow constrained BS power reduction (up to 6 dB) on active logical
channels iff BCCH carrier power reduction mode is enabled.

Take into account that the maximum power difference between a timeslot
used for BCCH/CCCH and the timeslot preceding it shall not exceed 3 dB.

Change-Id: I2cc6a86731984f586ef35b43a8d3de631f7d8a2f
Related: SYS#4919, SYS#4918
2021-07-05 12:17:59 +00:00
Vadim Yanitskiy ced29cf94c power_control: implement BCCH carrier power reduction operation
The BCCH carrier (sometimes called C0) of a BTS shall maintain
discontinuous Downlink transmission at full power in order to
stay 'visible' to the mobile stations.  Because of that, early
versions of 3GPP TS 45.008 prohibited BS power reduction on C0.

However, starting from version 13.0.0 (2015-11) there is a feature
called 'BCCH carrier power reduction operation'.  This is a special
mode of operation, where the variation of RF level for some
timeslots is relaxed for the purpose of energy saving.

In BCCH carrier power reduction operation, for timeslots on the
C0 carrier, except timeslots carrying BCCH/CCCH, the output power
may be lower than the output power used for timeslots carrying
BCCH/CCCH.  In this case the maximum allowed difference in output
power actually transmitted by the BTS is 6 dB.

Introduce a VTY command to turn on and off the BCCH carrier power
reduction operation.  Also introduce a CTRL command.  On the
A-bis/RSL, abuse the BS POWER CONTROL message by setting
the Channel Number IE to 0x80 (RSL_CHAN_BCCH).

Currently, only osmo-bts-trx is supported.  A value greater than
zero makes it reduce the power on *inactive* timeslots of the
BCCH carrier.  Sending zero disables the BCCH power reduction
mode completely.

For more details, see 3GPP TS 45.008, section 7.1, and 3GPP TR 45.926.

Change-Id: I047fce33d4d3e4c569dd006ba17858467a2f4783
Related: SYS#4919
2021-07-05 12:17:59 +00:00
Pau Espin a23eebb9a2 Support proto IPAC_PROTO_EXT_PCU BSC<->PCU
Related: SYS#5303
Change-Id: I4b3919f3098b9468e5e024db1e45427af24c1ad4
2021-06-30 08:13:37 +00:00
Vadim Yanitskiy 38a839e120 gsm_data.h: remove declaration of non-existing ts_pchan()
Change-Id: I2471d0f2825661e60539d9504632fc80145c603d
2021-06-29 15:10:30 +02:00
Pau Espin 883f067e62 pcuif_proto.h: Add new container messages
Related: SYS#5303
Change-Id: Icc50f903a7fe1464549537a24b2bd2befaf6f7e1
2021-06-25 08:17:21 +00:00
Vadim Yanitskiy d5db754514 PCUIF protocol: add message definition for interference report
Change-Id: I4bd5d4de695a1f9f202870cfd7e43caac9ce6d48
Related: SYS#5313, OS#1569
2021-06-22 16:56:54 +02:00
Neels Hofmeyr 68536ccf8b support A5/4 in inter-BSC Handover
inter-BSC into this BSC: from BSSMAP Handover Request, parse and store
Kc128. All else is already implemented: depending on the chosen
encryption algorithm, Kc128 will end up in the Channel Activation.

inter-BSC out of this BSC: nothing is needed to support A5/4, the BSSMAP
Handover Required message does not contain any encryption related
information. The MSC already knows the chosen algorithm.

Related: SYS#5324
Change-Id: I7e9590e8c96aa50086148863ad9a2741b978e614
2021-06-22 05:56:09 +00:00
Neels Hofmeyr 498e55a9a4 implement A5/4 in Ciphering Mode procedure
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
2021-06-18 23:31:31 +02:00
Pau Espin f274976df3 Introduce counters to track SRVCC procedures
Related: SYS#5337
Change-Id: I5c20da56d465dbcf4366130394f7c42635a24cc7
2021-06-17 14:05:40 +00:00
Pau Espin b9a6263823 Introduce VTY command to disable srvcc fast-return on target BTS
Related: SYS#5337
Change-Id: I2ac91b5dffc9b6de60576aabe21a15f24fea38cb
2021-06-17 14:05:40 +00:00
Philipp Maier 35b6b25433 handover_cfg: add missing VTY_CMD_PREFIX in comment
The comment that explains HO_CFG_ONE_MEMBER lacks VTY_CMD_PREFIX
in the sample macro definistion.

Change-Id: I80db198178cfd1e8669589eb3b468766f0c30ea2
2021-06-16 14:54:46 +02:00
Neels Hofmeyr b96ea3c97f gsm_data.h: add comments about immutable activ/modif/assign request info
Change-Id: I7997b802d997073ae6a05db2f40e82cb8e83764f
2021-06-10 16:15:35 +02:00
Neels Hofmeyr ee921cf903 VTY: add lchan re-assignment command
Add VTY command to trigger an intra-cell re-assignment, also allowing to
re-assign to a secondary VAMOS lchan.

Related: SYS#5315 OS#4940
Change-Id: If006f5caaf83b07675f57e5665cfa79328da55e6
2021-06-10 16:15:35 +02:00
Neels Hofmeyr d37dcb9f68 RSL: rx and tx VAMOS Channel Number cbits for VAMOS lchans
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
2021-06-10 16:15:35 +02:00
Neels Hofmeyr 43aeeaf05a RSL chan_nr: replace OSMO_ASSERT with error handling
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
2021-06-10 16:15:35 +02:00
Neels Hofmeyr 426941e87f update the lchan name to always reflect VAMOS shadowness
Change gsm_lchan_name_compute() to a function that in-place updates the
lchan->name. That allows calling it numerous times with the talloc
handled internally. Rename it to lchan_update_name().

Add 'shadow' to lchan_update_name() and lchan_fsm_update_id() for VAMOS
shadow lchans, and also print the lchan index that it is a shadow for,
instead of the index in the lchan array.

When set_pchan_is() updates the VAMOSness of the lchans, call
lchan_fsm_update_id(). From lchan_fsm_update_id() also call
lchan_update_name().

This is a bit convoluted for legacy reasons. There are utility programs
and C tests using bts_trx.c but not lchan_fsm.c. lchan_update_name()
lives in gsm_data.c for that reason. This patch calls
lchan_update_name() from lchan_fsm_update_id() and not vice versa to
avoid having to add stubbed lchan_fsm_update_id() functions to all
utility programs and C tests.

We can't easily unify the lchan->name and lchan->fi->id without lots of
refactoring rippling through all those little utility programs and C
tests.

Change-Id: I7c2bae3b895a91f1b99b4147ecc0e3009cb7439a
2021-06-10 16:15:35 +02:00
Neels Hofmeyr d163aa3805 add VAMOS secondary lchans to timeslot struct
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
2021-06-10 16:15:35 +02:00
Neels Hofmeyr 2aac1765e6 implement CHANnel ACTIVate to VAMOS mode
Related: SYS#5315 OS#4940
Change-Id: If3ac584e4223ef7656c7fedc3bf11df87e4309ec
2021-06-10 16:15:35 +02:00
Neels Hofmeyr 19d797c2fb lchan_fsm: introduce lchan.activate.ch_mode_rate to allow tweaking
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
2021-06-10 16:14:57 +02:00
Neels Hofmeyr edd5f5158d add lchan->vamos.is_secondary flag
VAMOS shadow lchans do not exist yet, but add the indicator flag that
tells whether an lchan pointer is a primary or a shadow lchan.

In Mode Modify: based on the flag, choose a different default TSC Set
for shadow lchans; do BTS type compat checking for shadow lchan use.

Actual lchans with vamos.is_secondary == true will be introduced by
patch: 'add VAMOS secondary lchans to timeslot struct'
I928af99498bba488d317693f3144d4fccbbe9af3

Change-Id: I4072fc7703c592df699fe8e27c02df09acde0909
2021-06-10 16:14:57 +02:00
Neels Hofmeyr e3e317242c implement Channel Mode Modify to VAMOS mode
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
2021-06-10 16:14:57 +02:00
Pau Espin a56b94ce0f vty: Drop unused old node enum fields
Change-Id: Ifccd1e477c36bee976a61760b0fedc395f675c1f
2021-06-09 12:02:52 +00:00
Neels Hofmeyr d9b7aedb77 change bs_power to bs_power_db
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
2021-06-05 14:35:16 +00:00
Vadim Yanitskiy cdaf3ec006 Make interference measurement parameters configurable
According to 3GPP TS 45.008, the BSS shall monitor the levels of
interference on its IDLE traffic channels.  The actual measurements
are performed in the BTS and then reported to the BSC over the
A-bis/RSL link(s) in RF RESource INDication messages.

3GPP TS 45.008 defines the following measurement parameters:

  * Intave: Interference Averaging period (see table A.1),
  * Interference level Boundaries (see table A.1).

Both parameters are sent to the BTS over the A-bis/OML, and can
now be configured via the VTY interface.  Only those BTS models
which 'speak' the OML protocol defined in 3GPP TS 52.021 will
actually get the configured parameters, others will keep using
the hard-coded parameters.

Change-Id: I99ebf57aac1f3ca7e0497c3b4f6b0738c6ed7e47
Related: SYS#5313, OS#1866
2021-06-04 19:42:43 +00:00
Neels Hofmeyr 3512e3cf1b drop unused func decl gsm_lchan_as_pchan2chan_nr()
Change-Id: I1c14e72d4387767349723ec8948149841b45d85a
2021-06-04 11:36:24 +00:00
Neels Hofmeyr 829c8e5052 Drop duplicated arfcn_range_encode.c available in libosmocore
This code is available in libosmocore since ~3 years ago
(fdf8b7b1beeb0cda262c5fb060a933aa7edb5e9a). Let's use it instead of
maintaining duplicated code which diverges over time.

Depends: osmo-bsc.git Iae058c35506bc25c9f4790889b89ac46aea664b6
(contains cherry-pick of bug fixed in osmo-bsc.git).

Change-Id: I53ad3067623077b6a8737c2a0aecc8b46bf71a15
2021-06-01 20:00:51 +02:00
Neels Hofmeyr 858a0211a0 lchan_fsm: introduce lchan.modify.ch_mode_rate to allow tweaking
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
2021-05-31 05:20:03 +00:00
Neels Hofmeyr 27c07690d9 replace ts_*_for_each_lchan() with ts_for_n_lchans()
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
2021-05-31 05:20:03 +00:00
Neels Hofmeyr e262919892 add fields to reflect nr of lchans in ts struct
So far the number of usable lchans is determined on-the-fly by the
physical channel config. With VAMOS, this becomes more complex, namely
determining whether the BTS is vamos capable.

Instead of calling a function to determine the number of lchans for
every use, rather place the number of valid lchans in int members of the
timeslot struct, and initialize those during timeslot setup.

Actual use of these new fields will follow in a subsequent patch, which
introduces the ts_for_n_lchans() macro to replace current lchan
iteration macros.

Related: SYS#5315 OS#4940
Change-Id: I08027d79db71a23e874b729c4e6173b0f269ee4f
2021-05-31 05:20:03 +00:00
Neels Hofmeyr c33eb8d569 allow explixit TSC Set and TSC on chan activ / modif / assignment
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
2021-05-31 05:20:02 +00:00
Neels Hofmeyr 5df7e771a8 gsm48_lchan2chan_desc(): expose TSC as param
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
2021-05-28 17:22:59 +00:00
Neels Hofmeyr 7336e63a96 add chan_mode_to_chan_type()
Move the conversion from chan_mode to lchan type out of the
lchan_select_by_chan_mode() function, so that the conversion can be used
by other code paths, coming up in VAMOS patches.

Related: SYS#5315 OS#4940
Change-Id: I296651ebadba81f8b3db0d9bb5b5377877a43677
2021-05-28 17:22:59 +00:00
Neels Hofmeyr 1b277ec2a2 RSL link: explicitly select rsl_link based on lchan
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
2021-05-28 17:22:59 +00:00
Neels Hofmeyr 69def1f97e hodec 2: do intra-cell congestion resolution by Assignment
So far we do all channel reassignments by Handover Command. Since
osmo-bsc now supports rassignment of ongoing voice calls, do intra-cell
congestion resolution by Assignment Command.

In effect, add support for expecting an Assignment Command in
handover_test, and expect assignments instead of handovers for
intra-cell congestion resolution test cases.

Related: SYS#5330 OS#3277
Change-Id: Id56a890106b93fcee67ac9401b890e7b63bba421
2021-05-28 17:22:59 +00:00
Neels Hofmeyr cb0aaad5d4 assignment_fsm: allow assignment to a specific lchan
So far the assignment FSM always tried to satisfy the channel mode and
rate by either re-using the current lchan or finding a new, unused
lchan. For VAMOS however, we want to pick one specific lchan.

Add target_lchan to struct assignment_request and skip all mode matching
and lchan selection when a specific target_lchan is set.

Related: SYS#5315 OS#4940
Change-Id: I71e0d4ff4746706e0be5266e4574d70ca432e3d7
2021-05-28 17:22:59 +00:00
Neels Hofmeyr d508143dd3 AMR config cleanup step 3: generate AMR LV on msg composition
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
2021-05-27 17:06:21 +02:00
Neels Hofmeyr 08e072bae0 move lchan->csd_mode into channel_mode_and_rate
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
2021-05-27 17:06:21 +02:00
Neels Hofmeyr 3625c90c22 eliminate lchan->rsl_cmode
Related: SYS#5315 OS#4940
Change-Id: I1c167b22bb6638a929488d093bde0f1a5fb227ad
2021-05-27 17:06:21 +02:00
Neels Hofmeyr 0951d75665 make sure channel mode and s15_s0 are updated only after an ACK
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
2021-05-27 17:06:21 +02:00
Neels Hofmeyr 5234c64bd0 assignment_fsm: send BSSMAP response only after Assignment Request
So far, only the MSC asked for Assignment via Assignment Request, which
we answer with a BSSMAP Assignment Complete or Assignment Failure when
done.

When Assignment is triggered for any other reason (congestion
resolution, VAMOS, VTY), we will not send any such messages to the MSC.

Additional enum values will be added in subsequent commits:
Id56a890106b93fcee67ac9401b890e7b63bba421 ASSIGN_FOR_CONGESTION_RESOLUTION
If006f5caaf83b07675f57e5665cfa79328da55e6 ASSIGN_FOR_VTY

Related: SYS#5315 OS#4940
Change-Id: Ie0cddbdb00abcec78e153f4ae6d04ce75080a111
2021-05-27 15:01:57 +00:00
Neels Hofmeyr d5cb0eb8fd lchan and assignment FSMs: make Channel Mode Modify more sane
The Channel Mode Modify procedure is currently implemented for changing
a TCH lchan from signalling to voice mode. For that, however, it is
re-using (abusing) the channel activation structs and state transitions,
and thus always implies activating a voice stream when the mode
modification is done.

I will add a Channel Mode Modify to enable VAMOS mode soon, so I require
separate structs and state transitions which also work on an lchan that
already has a voice stream established: a struct lchan_modify_info and
LCHAN_EV_REQUEST_MODE_MODIFY, and dedicated assignment FSM state
ASSIGNMENT_ST_WAIT_LCHAN_MODIFIED.

For the part where a Channel Mode Modify enables a voice stream after
switching from signalling to speech mode, still use the channel
activation code path, but only once the mode modification is done.

General improvements:
- To ask for a mode modification, emit an FSM event that ensures a mode
  modify only happens when the lchan state allows it.
- The new lchan_modify_info struct reflects only those parts that have
  an effect during a mode modification (before the lchan_activate_info
  was fully populated, many values not having an effect).
- More accurate logging, indicating "Mode Modify" instead of "Channel
  Activation"

A TTCN3 test for the Channel Mode Modify procedure is added in
Idf4efaed986de0bbd2b663313e837352cc139f0f, and the test passes both
before and after this patch is applied.

Related: SYS#4895
Change-Id: I4986844f839b1c9672c61d916eb3d33d0042d747
2021-05-21 15:43:30 +02:00