When doing analogue beamforming, the beam ID for a pre-defined beam
table is passed directly to RU and there is no need to store the beam
table in PHY.
Note: after this commit, monolithic works but nFAPI operation is broken
and fixed in the next commit, to keep the changes small(er). All
simulators work.
This commit removes the use of msgDataTx's intermediate buffers for FAPI
messages and the call of the "Schedule response". The latter incurs an
additional copy of FAPI messages for the TX chain (for the RX chain, it
is and will remain there) which we can avoid.
Instead, it uses an NR_Sched_Rsp_t-typed variable sched_response to
store the results of the scheduler when called from tx_func(). Thus, the
scheduler remains unchanged (it gets a pointer to where to put FAPI
messages), but we don't call nr_schedule_response() to then copy FAPI
messages into the L1, but have them in a local variable sched_response.
sched_response on on the data segment, as it is big and would overflow
the stack; at the same time, this is ok because only one tx_func() runs
at a time.
Since we don't use allocate_sched_response() anymore, we don't need
deref_sched_response().
clear_slot_beamid() is moved to tx_func(), as it was called in
nr_schedule_response().
Since the "intermediate" NR_gNB_DLSCH_t structure groups both the
DL_tti_pdsch and TX_data.req structures, a pointer has been created to
point to pdsch_pdu. This affects a number of simulators, as they have to
put some messages on the stack:
- nr_dlschsim: put the corresponding variable on the stack
- nr_pbchsim: a new array for the SSB PDUs has been introduced
Further, these changes are now necessary:
- nr_dlsim: there were variables "rel15" and "pdsch_pdu_rel15" that
point to the same PDSCH PDU. At least "rel15" would not exist, as the
corresponding pointer is now populated in phy_procedures_gNB_TX(), and
we therefore refer to the single PDSCH PDU variable with
"pdsch_pdu_rel15", but at the place where "rel15" used to be
initialized.
- nr_ulsim: use nr_save_ul_tti_req() to load PDUs into the RX chain
instead of nr_schedule_response(), which does not exist anymore.
The next commit will remove msgDataTx. We can therefore not use
msgDataTx to retain the PDSCH/DLSCH variables, and move them to the gNB.
Note that the only reason for NR_gNB_DLSCH_t after this commit is to
hold various large buffers (c, b, f). Future work could be done to
remove this, in which case the array inside PHY_VARS_gNB could be
deleted.
On this occasion, clean up the use of init_DLSCH_struct() and
reset_DLSCH_struct() (renamed destroy_DLSCH_struct()) and centralize
their call in phy_init_nr_gNB()/phy_free_nr_gNB(), and correct
simulators accordingly.
There is no point in tracking the "active" state: the SSB PDU will be
sent from MAC to L1, encoded, and then "discarded" (by marking the
number of SSB PDUs as 0). Hence, remove this intermediate type.
Refactor DLSCH scheduler
Refactor the DLSCH post processor similarly to what has been done in
!3521 with the goal of saving an additional iteration through all UEs,
hopefully making the DLSCH scheduler faster.
It further includes changes to make working with and debugging multi-UE
operation easier:
- add some measurements in L1 (for total TX/RX time)
- a new option MACRLCs.[0].stats_max_ue to limit the number of UEs in
the periodic output (default: 8, 0=disable)
- avoid stack overflow in the MAC
- fix the writing of stats to nrMAC_stats.log and nrL1_stats.log when
the written output reduces by truncating the files
- avoid to schedule retransmission with 0 RBs.
saves about 600MB of memory allocation
Move the definition of PRACH items and the PRACH list to the
defs_nr_commons.h file.
Do not re-write the entire structure in nr_schedule_rx_prach(), as it is
quite large now.
fix direct bugs of not used RU_RX_SLOT_DEPTH defined constant
with this commit, the gNB can work if we change RU_RX_SLOT_DEPTH to
another value than 4 but it remain not well designed
UE symbol based PDCCH receiver
This is a partial rebase/rewrite of !2895
The goal of this MR is to check how we can merge this.
The eventual result is stated in !2895. The way forward is to modify UE
RX procedures to work symbol by symbol by extracting the symbol loop out
of RX procedures. After all channels are modified this way, the main
thread can be modified to work symbol by symbol.
At this point only PDCCH was modified.
1.Create new funtion nr_symbol_fep() to do OFDM demod of one symbol on
all antennas. This is called by nr_slot_fep() for now. In the
upcoming MR, this function will be called directly after reading
each OFDM symbol from the radio.
2.Removed redundant memory alignment. DFT function performs memory
alignment if the input memory is not aligned.
Support beam index in OAI 7.2 Fronthaul Interface
This branch supports beam index in OAI 7.2 Fronthaul Interface.
- For CP DL (PDSCH), nBeamIndex of the corresponding prbMapElm is set
when sending IQ data in oran_fh_if4p5_south_out. nBeamIndex of the
corresponding prbMapElm is set when sending IQ data in
oran_fh_if4p5_south_out.
- For CP UL (PUSCH and PRACH), nBeamIndex of the corresponding prbMapElm
is set in oran_fh_if4p5_south_out.
In addition, it fixes a couple of issues
- XRAN hardcodes nBeamIndex of PRACH to zero. Modify XRAN to support
setting of nBeamIndex of PRACH and update xran F release patch.
- Fix the bug in calculating fh_config->neAxc where num_beams_period is
multiplified twice
Testing methodology: Use Benetel O_RU for testing even though it does
not support beamforming. With successful registration and data transfer,
one could check the pcap on the fronthaul interface to see if CP packets
are with the right beam index.
Results:
1. Verified that CP-packets for SSB, DCI, PDSCH, PRACH, PDSCH, PUSCH,
CSI-RS and SRS are with the right beam index
2. Verified that there is no side-effect on Benetel O_RU. UE could
register properly.
3. Verified 4 SSB with ssb_PositionsInBurst_Bitmap = 85. Could see SSB
and PRACH with 4 different indices.
RF simulator: Fix concurrency issues during new client connections
- Fix concurrency issues happening when a new client connects, sometimes
leading to a total softmodem deadlock.
- trace in 4G RAR processing to debug ci result
Do not pollute periodic output, and rather print those into
nrL1_stats.log. A number of them are already there anyway, so transfer
the rest. Note: ru->ifdevice.tx_fhaul is omitted, as we don't have any
IF5 split in 5G.
The queue L1_rx_out was in place to keep RX/TX processing relatively
"close" to each other (in terms of time, since in RFsim, they might
advance faster than realtime; see also parent commit). This lead to a
memory leak in radios that do not use ru->feprx (no front-end processing
for RX, e.g., PRACH), as the code to read the L1_rx_out messages was
inside a block of if (ru->feprx). Move it out so that the queue is
always read and messages are freed to eliminate the memory leak, and
remove the workaround for FHI72 to avoid this memory leak.
This also allows to run RFsim when compiling FHI72, which was not
possible before this commit.
Closes: #812
Repair nFAPI in 5G
Add 5G nFAPI in OAI/Make it it work.
Many commits in this branch are basically bug fixes of things that don't work
properly, such as
- check for correct conditions (e.g. instance numbers in the RAN context)
- remove artificial limitation (e.g. only one PUCCH per TDD period in the PNF)
- improve performance (reduce big mallocs, make some static buffers such as a
global ring buffer for nFAPI messages in the PNF)
- fix bugs in nFAPI (e.g., increase maximum message size to ~64kB instead of
1500 bytes, because the latter is way too small for many TX_data.requests in
5G, and it will delay message arrival unduly)
- fix bugs in message enc/dec (e.g., handle FDD in config.request)
- adjust the L1 such that the condition "we run monolithic" is not necessery
(e.g., some message numbers in nFAPI struct where reset in MAC, instead of
L1, and this breaks when running the PNF)
There are instructions that explain how to set it up. Two CI tests have been
added, one with COTS UE and MIMO in DL+UL in TDD numerology 1 (30kHz), and a
second test with FDD mu=0 (15kHZ) in RFsimulator.
These were some old to-dos that have been addressed.
- test with COTS UE - 4x4 pipeline works good in DL, UL now also work
- test in RFsim
- make PNF status message
- make FDD in u0 work
The usage of this flag in the L1 is simply wrong: either, the NFAPI mode
runs L1, or not. Correspondingly, add an assert to check this invariant.
In the NR_IF_module, the correct check to do is for VNF (implying no L1,
or "emulation of L1" [which is not true]), in which case we use
queues.
In monolithic, the sched_response mechanism ensures that FAPI messages
for one slot are not overwritten by scheduler instructions for the
following slots (i.e., it is like a memory allocation pool).
The allocation happens in nr_schedule_response(), not used by the PNF.
Hence, only deallocate when in monolithic.
The PNF uses a big ring buffer over all slots in a frame to ensure the
same.
Now uses RC.nb_nr_L1_inst instead of RC.nb_nr_inst in order to configure the L1, since in PNF RC.nb_nr_inst is always 0, and so, it wouldn't configure the L1
Move UL_INFO structure allocation local to a rx slot processing
UL_INFO is allocated a gNB, so require mutex and obscur information
passing function to function. Instead, make a local UL_INFO per slot,
removing the mutex and making the code easier to understand.
Use UL_INFO on the stack, to simplify the code. move in the same struct
the associated rach, pdu, crc, srs arrays that where pointed from
directly in gNB structure Keep in nfapi the existing logic that make
malloc for theses rach, pdu, crc, srs array lists
Pass only relevant fields, where appropriate.
Co-authored-by: Robert Schmidt <robert.schmidt@openairinterface.org>
Add support for O1 in O-DU via telnet
This change set adds a simple telnet interface to nr-softmodem. Together
with oai/o1-adapter>, this implements a part of the O1 interface, for
the DU only. Currently supported uses cases:
- some stats are send to an SMO (such as bandwidth, PLMN, frequency, ...)
- re-configuration of bandwidth, frequency
- stop/start of the softmodem, while keeping the CU and L2 running
- the o1-adapter implements two alarms, load overload and base station
offline, using this interface.
It is possible to use the telnet interface by itself (i.e., "o1" without
the o1-adapter). To do this, compile with telnet support (./build_oai
--build-lib telnetsrv) and start the nr-softmodem with O1 module
(./nr-softmodem --telnetsrv --telnetsrv.shrmod o1). You can then do the
following:
- see some statistics as exposed to o1-adapter, in JSON: echo o1 stats | nc 127.0.0.1 9090 && echo
- stop the L1: echo o1 stop_modem | nc 127.0.0.1 9090 && echo
- reconfigure bandwidth: e.g., echo o1 bwconfig 20 | nc 127.0.0.1 9090 && echo (also supported: 40, 60, 100)
- start the L1: echo o1 start_modem | nc 127.0.0.1 9090 && echo
Note that the reconfiguration works with split-8 radios. Notably, it
does not work yet out-of-the-box with 7.2 radios, because they have to
be manually reconfigured on bandwith/frequency switch. The planned
M-plane should allow such use case, though.
To help with the above, this branch also includes fixes (for more
information, refer to the corresponding commits):
- fixes for stopping the L1, notably stop threads in right order, stop
thread pool of RU
- collect some general MAC metrics, fix some bugs in MAC
- fix problems in F1AP gNB-DU configuration update message, update test
- fix some problems in RRC
These are the "main" worker threads (apart the ru_thread). If the
thread-pool stops, they might get stuck. E.g., in PUSCH channel
estimation, it uses a local response queue, and if the thread pool is
terminated, it seems that the L1_rx_thread can get stuck in there.
To limit these problems, attempt to stop these threads first; stop the
queue from which they read and make them terminate; then, stop the
thread pool.
Also, fix the termination of respPuschSymb queue.
* the goal of this function is to initialize and configure the RAN Context
* the goal of get_options is to get command line options
* this commit aims at making the implementation more consistent
* move initialization of RC.nb_nr_CC to this function
* cleanup redundant initializations of RC.nb_nr_macrlc_inst outside NRRCConfig
* cleanup redundant initization of RC.nb_nr_macrlc_inst from getter function (get_node_type)
* cleanup RC initialization in RCconfig_NR_L1
* removed redundant log lines (print number of instances in NRRCConfig only)
* do RC init after getting CL options and configuration
* get_node_type shall access configuration only, not RC context
* NRRCConfig shall be called only once: made it thread-safe
* nb_nr_inst represents the number of gNB instances and the number of RAN contexts
* it used also to count the number of RRC instances in the node
* it is set from config file in NRRCConfig, therefore redundant checks after
this function have been removed
* redundant global variable NB_gNB_INST, set after nb_nr_inst, was removed
This commit removes many logs that just show memory addresses, indices,
etc., which, I presume, do not mean anything to the "average user" and
developers alike.
francescomani