Split out type and function definitions for a cleaner separation for
some consumers of these functions. Concretely, nr_mac_common.h includes
various ASN.1 NR RRC headers, but not all consumers of these APIs might
need these headers. For instance, the next commit will use these
functions in the driver for 7.2 (it needs to compute PRACH length), but
the driver itself does not depend on nor does it need the ASN.1 NR RRC
headers. Defining a new header avoids the problem.
1. The encoder writes the output in sequence after the encoding tasks completed instead of writing within the tasks.
2. Simplify the output writing to make it more readable.
Co-authored-by: Laurent Thomas <laurent.thomas@open-cells.com>
There was a risk of a race condition between encoding tasks on the output array.
It could be that two task compete in writing a word at the border of their respective segment groups.
This commit offers to solve this issue by retaining the tail word in a struct that is returned after task completion so that segment group border can be fixed after completion of all the tasks.
Comes with additional cleanups of nrLDPC_coding_segment_encoder:
1. Move the section of code dedicated to writing to the encoding library output to a separate function.
2. Remove bit interleave debug in AVX512VBMI case of output writing for improving code readability.
1. nrLDPC_coding_segment_encoding: Clarifying encoder parameters
The way the encoder implementation params was used could be made clearer:
* `macro_num` was always used in order to calculate segment indexes.
It is clearer to pass directly the first segment index.
* The initialisation of a common implementation parameters structure can be made clearer.
2. nrLDPC_coding_segment_encoder: Remove multi segment dimension in encoder output
The output of `LDPCencoder` was a 2D unsigned char array.
But all the segments were actually packed in the first segment, 8 bits of different segments per byte of the first segment.
So the first dimension was useless. This commit removes this dimension.
3. nrLDPC_coding_segment_encoder: Rename `nrLDPC_prepare_TB_encoding` into `nrLDPC_launch_TB_encoding`
4. nrLDPC_coding_segment_encoder: Remove the useless second rate matching for E2, one rate matching with max(E, E2) does the job.
5. nr_interleaving_ldpc: cleanup
Rewrite code to use different SIMD sizes in a linear fashion.
This means cascading preprocessor directives are used to start from a high SIMD size an decrease it progressively.
6. ldpc_encoder_optim8segmulti: linear usage of SIMD
Use cascading preprocessor directives to include different SIMD sizes and types depending on which are available on the system.
The different loops use a common index that is progressively incremented.
Also add AVX512 version of bits distribution from 8 segments into one byte.
Co-authored-by: Laurent Thomas <laurent.thomas@open-cells.com>
Since this branch aims to bring all the encoded segments packed and contiguous,
it doesn't make anymore sense to have one output array per segment.
Therefore this commit moves the output array to the TB instead of the segment and adapts its size.
TODO: Adapt the size of f where it is relevant.
1. nrLDPC_coding_segment_encoder: pointer not aligned on 64 bits
An undefined behavior was happening because of a shift on a __m64 which
was actually a uint32_t which was not aligned on 64 bits.
This commit suggests a fix by properly loading into a __m64 with _mm_set_pi32
before performing the shift.
2. nr_rate_matching: Filler bits detection
Previously, if the bit selection was reaching Ncb and restarting selection from the beginning of encoded data, the filler bits were detected by testing the bytes again NR_NULL which was equal to 2.
But on this branch the bits of up to 8 segments are stored in one byte while doing rate matching so that one byte could be tested to be a filler while it is not.
So this commit changes the way to test filler bits.
Instead of relying on NR_NULL, bit selection now relies on the offset and size of filler bits.
3. nr_ulsch_coding: missing filling f with zeros
The array `f` of the UE UL HARQ process was not filled with zeros between transmissions.
This is a problem if the encoder does not properly overwrite its output.
In order to avoid such situation, this commit adds a memset to fill `f` with zeros before passing it to the encoder.
4. nrLDPC_coding_segment_encoder: missing init of f to zeros
In the encoder, `f` is not filled with zeros before being used.
`f` is instead somehow filled with arbitrary values.
When writing to `output` by 64 bit vectors, some arbitrary bits may be added after the segment.
Then the arbitrary added ones are not overwritten when writing the next segment because of writing with a logical or.
This commit properly fills `f` and `f2` with zeros.
5. nr_ulschsim & nr_dlschsim: Adapt modulation to new encoder output
The QPSK symbols that are feed to the channel model of nr_dlschsim were determined based on the bytes of the encoder output.
With the new output of the encoder, it had to be reworked to determine the QPSK symbols based on the bits of the encoder output.
The fronthaul library ships with BFP compression for AVX512 enabled targets.
This commit adds BFP compression for Arm targets by using the ArmRAL library.
Update the xran E release patch to work for Arm targets in addition to x86 targets.
Co-authored-by: Yi-Hung Chang <Yi-Hung.Chang@eurecom.fr>
Co-authored-by: brobert <brobert@valiha.com>
1. Change the name of `openair1/SIMULATION/NR_PHY/nr_dummy_functions.c` into `openair1/SIMULATION/NR_PHY/nr_unitary_common.c` for naming coherence after adding the SIGINT handler which is not a dummy function.
2. Instead of being built once for every NR PHY simulators, the common functions source file is built once as an object and linked to each simulator.
Even though the remaining NR PHY simulators do not use the T2, we may still feature them with a SIGINT handler for proper termination on SIGINT and for a matter of completeness.
The remaining NR PHY simulators are:
* nr_pbchsim
* nr_prachsim
* nr_psbchsim
* nr_pucchsim
There was two issues that were making nr_ulschsim non functional:
1. The channel output was not copied to decoder input (llr array)
2. The test on decoding successful outcome was wrong
The result was that nr_ulschsim was succesfull whatever were its arguments.
This commit fixes the two issues so that nr_ulschsim is now functional.
When using T2 virtual functions, it is important to properly stop DPDK and free the device.
Otherwise the virtual functions may be blocked and a restart of the admin application is necessary.
Up to now, SIGINT was shutting down the PHY simulators without freeing the device.
This commit adds a signal handler to handle SIGINT in a way that allow to properly free the device.
This feature is first added to the PHY simulators that use the T2 which are `nr_ulsim`, `nr_dlsim`, `nr_ulschsim` and `nr_dlschsim`.
The idea is to make LDPC iteration accounting more standard from a C coding perspective by making two changes:
1. Now the iteration counter starts at 0 for the first iteration and goes up to max_ldpc_iterations - 1 for the last iteration.
If it is equal to max_ldpc_iterations, it means that decoding failed.
2. A chain of useless returns in the UE DLSCH decoding call chain was removed.
The logs of `./nr_ulsim -n100 -m19 -s12 -S12 -z2 -L4` were showing that sometimes the decoding of one segment was failing while the CRC check succeeded.
This was happening because the iteration counter `numIter` was not properly managed so that when the last iteration was successful to decode the segment
still `numIter` at the exit was equal to `numMaxIter` plus 1 so that decoding was considered to have failed.
In other words the last iteration if it occured was always wasted.
This commit offers to solve this problem by simply moving the iteration counter increment at the end of the iteration loop
while remaining careful at fixing the tests relying on this counter.
The variable block_length had an ambiguous role and was used as both K and Kprime.
This was leading to arrays with wrong sizes and functions with wrong arguments.
Now there is not anymore block_length but K and Kprime.
Kprime can be set with the command line argument `-l`.
There was also some problems with array allocation for segments with length not divisible by 8.
A proper sizing with `((size_in_bits + 7) & ~7) / 8` was used.
A proper masking of the last byte containing payload bits was also added to keep filler bits to 0 after random initialization.
The name ldpc8blocks_coding_segment was previously used to avoid any confusion with ldpc8blocks while both were coexisting.
They are not anymore coexisting so it can now be shortened.
While timers were available for rate matching and interleaving in the new interface,
these timers were not merged to rate matching and interleaving timers in nr_dlsch_coding.
LDPC coding was yet not properly stopped by using free_nrLDPC_coding_interface in gNB and UE.
This was not causing major issue until now. It was especially not causing any issue with T2 LDPC coding using the PF.
But using T2 VFs, if the coding library is not properly stopped then the VF cannot be used anymore unless the admin app is restarted.
So this MR adds the missing free_nrLDPC_coding_interface.
The offset provided for each code block in the HARQ combined input and output buffer shall not be above 512.
A modulus was performed on the offset of the TB in the buffer to avoid this situation.
But the offset of the code block was added afterward so that the total offset was sometimes going above 512.
This commit performs the modulus after adding the code block offset.
More complex implementations will be achieved using the new reworked interface
- t_nrLDPC_dec_params: remove F, Qm, rv and perCB
- encoder_implemparams_t: remove Qm, Tbslbrm, G, rv and perCB
In phy-test, the scheduler has a hardcoded UE allocation; if CQI and RSRP
are not evaluated, there is no change in the scheduler function. Also,
this avoids misleading error messages if no UE is connected.
Romain Beurdouche