Add symbol timing functions for NR_DL_FRAME_PARMS + optimization for slot timing
counterparts
Add two new functions for calculation symbol timestamp and symbol duration for
NR_DL_FRAME_PARMS. Also includes an optimization focused on removing
inefficiencies related slot-related counterparts.
1. Removed function pointers for functions get_samples_per_slot(),
get_samples_slot_timestamp() and get_slot_from_timestamp() as it does
not offer any advantage. The functions are now called directly from
everywhere.
2. Optimized these functions by removing loops where ever possible.
NR UE: calculate TA based on SIB19 information in NTN mode, if autonomous TA is not enabled
To achieve the goal, the hyper frame number (HFN) is introduced at the NR UE
PHY, MAC and RRC layers.
Besides this, we also implemented an orbit propagation to improve the accuracy
of N_UE_TA_adj, and a fix to keep the N_TA from RAR and MAC CE.
Fixes#981
E2SM-RC RRC message forwarding (e.g., to signal a new UE, measurement
reports, ...) was broken since commit d6c29b2d2c, as we accidentally
removed the E2_AGENT compilation definition from RRC layer.
Although this commit fixes the mentioned issue, it also causes undefined
references to functions defined in ran_func_rc.c file. Therefore, we
add a hack that provides the definition, and abort if we ever hit these
functions, which in theory should not happen.
Future cleanup should avoid linking in RRC and other layers into
simulators.
Fixes: d6c29b2d2c ("Fix E2_AGENT linking w.r.t. simulators ")
Hide normal table initialization of Ziggurat generator from outside to
force the usage of randominit() for RNG initialization. In this step,
remove the randominit() seed parameter and only rely on OAI_RNGSEED for
a consistent RNG initialization, as this parameter was used differently
("0" as fixed number or to force a random seed).
Now, only use OAI_RNGSEED env variable to force the usage of a fixed
seed.
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.
DLSCH encoding is not concerned with HARQ processes directly. Instead,
it gets the redundancy version and encodes a specific redundancy version
for a given TB. The rest is up to the MAC, the L1 is stateless in that
regard. Hence, remove the HARQ type and put it into DLSCH, which also
simplifies the code elsewhere.
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.
Call the post-processor when the allocation is "fixed" (i.e., nothing
changes anymore), instead of having a final loop across all UEs that
might potentially be costly.
In order to calculate the PF metric, note that the statistics "reset" is
moved into pf_dl() instead of the post-processing loop, as it has to be
done on each slot.
See also: dd98030202 ("Refactor to call post-processor in place")
Similarly to parent commit(s), assign sched_pdsch in a single place
instead of relying on sched_ctrl. In a follow-up commit, the
post-processor will be called in a single place.
Reworking BWP configuration
This MR reworks the configuration via fail of additional BWPs. Moreover, it
allows for a single BWP to be configured for a given UE at a given time (BWP
switch possible only via reconfiguration). It also reworks PTRS configuration
for consistency with the BWP one.
If the DCI in PDCCH is not correctly received, no PDSCH would be decoded but counted as no error.
Also if the DCI was not correctly received, a TBS of 0 would be used in some computations and memory allocations.
Fix these not counting if there is no PDSCH decoding, and by using the known TBS instead of the one received from the DCI.
Ldpc encoder zc384 optimization
This is a modification for the ldpc encoder which improves performance for
high-throughput cases. It contains a newly-generated file for innermost part of
the parity bit generation which, for AVX512, uses the mm512_permutex2var_epi8
instruction and for 128-bit (aarch64) the mm_alignr_epi8 (vextq_s8) in the
computation corresponding to each non-zero bit of the H matrix. This allows for
removing a very large memcpy and reduces the memory demand for the parity matrix
computation. For the moment this is limited to largest case in BG1, namely
Zc=384. This is the only format used when the number of segments after codeblock
segmentation is large (>8). This improves the timing required for ldpc parity
bits generation by more than a factor 2 with AVX512. This significantly reduces
the total time to generate the DLSCH/PDSCH.
See the merge request description for numbers.
- Use MAX_NUM_NR_UE_INST in NR UE MAC to control number of MAC instances.
- Modify the MAC interface slightly so that nr_l2_init_ue only initializes one instance
Remove the --usim-test option: to my knowledge, it's not used by users,
and is misleadingly placed in various places where there should not be a
difference w.r.t. USIM configuration.
When making the changes, I assumed that --usim-test would be 0 (the
default), which is the case in all executables when not specified in
options except for the nr_dlsim, nr_pbchsmi, nr_ulsim simulators.
The only exception is the initialization of PDCP from the MAC, which is
not correct (the PDCP is in the CU, so it does not make sense to call it
from the MAC which is in the DU). Instead, always initialize from main,
even in the NSA case (NSA was covered by the incorrect initialization
from MAC).
This in turn let to some more cleanup around function du_rlc_data_req().
After receiving GTP packets at the DU, they were given to the PDCP to
enqueue the packet at RLC. This does not work anymore, since the PDCP is
not initialized; it also does not seem necessary, as this enqueue
functionality is necessary to decouple PDCP and RLC to avoid deadlocks
in monolithic, but in split-mode, this cannot happen. Instead, call
directly into the RLC when receiving GTP packets.
Recently f buffer was changed to hold packed bits and the correspoinding
change in dlsim was not done so the number of error bits before decoding
was incorrectly reported. This commit fixes it.
NR RRC Reject UE
Improvements in procedures to handle RRCReject message both at gNB and
UE. At gNB we send RRC Reject if the UE cannot be given resources to go
into connected mode.
- remove hardcoded values
- adapt gNB RRC code
- adapt gNB MAC code
- adapt physical simulators, where we put the hardcoded values
that were everywhere else before; if there is a need for those
simulators to get configurable values, more work is needed
(but it's doubtful that it is needed)
A number of radio-related RRC parameters, e.g., CellGroupConfig,
"originate" at the DU and are sent to the CU for forwarding to the UE
only. Similarly, there are additional parameters, e.g., RLC-BearerConfig
(part of CellGroupConfig), that originate at the DU.
Hence, the DU decides about these parameters, depending on the MAC state
and capabilities. To clarify this, move the existing
openair2/RRC/NR/nr_rrc_config.{c,h} => openair2/LAYER2/NR_MAC_gNB/nr_radio_config.{c,h}
So that developers know that while those are RRC parameters, they
originate at the DU.
In other words, the CU/RRC is not supposed to use any of these functions
in the RRC. Correspondingly, includes of this file have been cleaned up
(and when they are not necessary at the MAC as well).
- Change return value of nr_dlsim, nr_pbchsim and nr_pucchsim to:
- Return '0' if test succeeds (indicated also by "PDSCH/PBCH/PUCCH test
OK" in the test log).
- Return '1' if test fails.
- rewrite add_UE_to_list() and rewrite remove_UE_from_list() to simplify
list handling
- return pointer from get_new_nr_ue_inst(); it's completely freed by
delete_nr_ue_data()
- have add_new_UE_RA() add UE context to access list; remove with
nr_release_ra_UE()
- have add_connected_nr_ue() only add UE to connected list; to move from
access to connected use transition_ra_connected_nr_ue(); remove with
mac_remove_nr_ue() as previously
- free memory on problems during RA
- add some documentation
- in NSA/HO: check for pre-configured RA process
- there are asserts in all functions to clarify when a UE has RA