* assuming num_dl_slots and num_ul_slots are including also
slots with dl/ul symbols respectively
* refactor set_tdd_config_nr
* moved function to MAC
* fill max_num_of_symbol_per_slot_list depending on slot type
* use new set_tdd_config_nr in stack
* minor refactor in config.c to improve readability (scs)
Co-authored-by: Guido Casati <guido.casati@firecell.io>
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
This function packs P7 messages. At least RX_data.indication messages
might be much bigger than the global buffer that is used here. Allocate
the buffer on the stack, and make it bigger. Do not use the global
buffer, it's simply not necessary; increasing the global tx buffer size
might have negative effects elsewhere in the code.
That change might make the function reentrant. The mutex seems to only
guards the codec config. However, leave it to not introduce any
regressions as of now.
Similar to the parent commit, make the numerology in the VNF
configurable. Unlike for the PNF change, the VNF frame/slot info is in a
per-PNF connection structure to which the "oai_integration" code has no
access. So we need to hack the nfapi_vnf_p7_add_pnf() function signature
to take the numerology, to be able to save this on a per-PNF basis.
The fact that we store this on a per-PNF basis is not strictly required,
as the VNF cannot handle multiple numerologies as of now, either.
However, we might want to extend this in the future, so it seems prudent
to store this on a per-PNF basis, so that we could start handling
multiple numerologies at the L2 without the need to change the L1 or
nFAPI code itself.
Also, the numerology is not needed except for some code that deals with
timing over nFAPI. As of now, we don't use this code (nFAPI gets a
trigger every slot, as per the VNF request, see an earlier commit in
this series), but also here, let's not make the future more complicated
by storing the numerology for each PNF now (this could always be reverted).
For 4G, put numerology 0 (15kHZ SCS), which is the SCS that LTE uses.
At both the PNF and the VNF, introduce a separate numerology field, and
pass the numerology when converting time information using macros from
nfapi_interface.h. The actually numerology is still hardcoded to 1 (as it
was before), but the follow-up commits will put a suitable numerology.
In both cases, but the numerology next to the frame/slot information.
The next commits will modify the time macros used in the 5G nFAPI code
to handle different numerologies. As a preparation, remove all the
usages of these macros where they really don't matter (e.g., don't
convert if we don't need to).
the L1 needs both a PDU (in TX_data.req) as well instructions for
the actual transmission (in DL_TTI.req) to encode a PDSCH message. In
nFAPI, it can happen that a DL_TTI.request message has been received
(configuring the PDSCH transmission), without the TX_data.request having
reached the PNF. The L1 assumes to have the PDU.
To avoid problems, ensure that only the pair of DL_TTI.req/TX_data.req
is delivered. Otherwise, drop either message.
nFAPI has a mechanism to segment messages that are too big for transport
over a given medium (see e.g. SCF 225, section 2.3.2).
The maximum segment size of 10000 makes that for larger payloads, e.g.
TX_data.request, many small segments are to be sent. This can create or
increase delays on the transport. On the other hand, the currently only
available transport mechanism, UDP, allows to transport packets of up to
almost 65535 bytes. Correspondingly, increase the maximum segment size
so that less segments are to be created, and potentially, less delay is
to be incurred. # Please enter the commit message for your changes.
Lines starting
Avoid delays in tx_data.request handling by avoiding big malloc()s and
copy operations. Reimplement function to (1) peek the frame/slot
numbers, (2) decide on buffer, and (3) unpack directly into
pre-allocated memory.
Co-authored-by: hsum <ming-hong.hsu@eurecom.fr>
Co-authored-by: chenyi <Yi-Quan.Chen@eurecom.fr>
Co-authored-by: Rúben Soares Silva <rsilva@allbesmart.pt>
The next commits refactor the rx handling of messages in the PNF. To
efficiently handle them, provide a "peek()" function that gives us the
frame/slot for which a message is destined. This allows to decide if a
message is on time and select a destination buffer, before unpacking it
completely, avoiding copies.
The time that a message between PNF/VNF to arrive depends mostly on the
transport. To allow for some delays, there is a slot_ahead time, during
which the VNF is allowed to schedule and send instructions to the PNF.
This can be multiple slots; the 1ms hitherto given might typically too
short. Increase to 10ms, to encompass a wider range of slot_ahead times.
Make the corresponding log message of when old (stale) message are
removed a bit clearer with respect to times.
This is the first commit in which nFAPI works. Follow-up commits improve
performance.
The function now utilizes simpler variable names and logic to determine
if a given NR P7 request falls within the timing window.
The logic for determining if a request is within the timing window is as follows:
- The function calculates the absolute difference between the current
and received SFN slots, taking into account the possibility of
wraparound.
- If the absolute difference is greater than half of the maximum SFN
slot value, it subtracts this difference from the maximum SFN slot
value to get the actual difference.
- The function then checks if this difference is less than or equal to
the specified timing window. If it is, the request is considered to be
within the window.
Additionally, the commit updates the function signature to return a
boolean value for better readability and consistency.
Changes made:
- Simplified variable names for readability
- Improved logic for handling wraparound scenarios
- Updated function signature to return a boolean value
Co-authored-by: Rúben Soares Silva <rsilva@allbesmart.pt>
This function applied an sf_ahead, bigger than the actual slot
indication message sending (so a message could NEVER arrive on time!).
Reduce to zero, because this is when it should arrive for us.
The previous designs seems to do:
loop {
poll_ind_queue()
if (msg)
scheduler;
pselect() on messages;
handle_message {
if slot_ind
put_ind_queue()
}
}
So basically, we artificially put a queue for slot indications in the
middle, but still handle it in the same thread(!). This for some reason
results in a big slow down if the PNF runs faster.
Now, we just do pselect(), waiting for messages. We handle the slot
indication immediately (the schedule should take some microseconds),
then return to pselect().
This is to align with monolithic/FAPI, where we get slot indications in
each slot. In the nFAPI, this is replaced by timing information, such
that the VNF ticks automatically, and gets indications from the PNF on
early/late messages. The timing information handling is not implemented
in the present nFAPI implementation. Instead, we adopt the FAPI behavior
and send timing information in every slot, abusing it to be a slot
indication.
Add a small FAPI Hex parser utility
Adds a small FAPI hex parser utility nfapi_hex_parser, that takes in a FAPI
message hexdump, either from the command line or a file, unpacks it and prints
the contents out to the console.
The functions to print the data to the console were added alongside the existing
utility functions, for both P5 and P7 messages.
This allows the user to quickly check if a message has the valid format to be
unpacked in OAI.
The file examples.md contains some examples of execution and output.
This utility is compiled alongside the NFAPI_LIB, as such, it is compiled
whenever we compile nr-softmodem, or any other target that uses the NFAPI_LIB.
Add utility functions to print the FAPI messages contents
Add dump functions for DL_TTI.request PDUs, remaining message structures to be finished
Add file examples.md with some examples on how to use nfapi_hex_parser
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>
The parent commit cleans up and groups oai_exit in one place,
nr-softmodem-common.h. Therefore, this 5G file is included in the 4G
defs_common.h (at least it's mostly 4G), which is not nice. Instead,
define oai_exit also in 4G softmodem-common.h, and include this in
defs_common.h. Remove the cyclic inclusion of defs_common.h in
softmodem-common.h, and resolve all subsequent errors around unknown
types and extern definition mismatches.
Updates to match more fapi-compliant tx_data.request
The packing of PDUs as required in aerial for the Tx_data.Request wasn't
complaint with FAPI. That was fixed in Aerial 24-2. This change makes L2
pack the payloads in the way that Aerial now requires.
This change makes it so the fapi_nr_p7_message_pack is used to pack TX_DATA.request for Aerial, reducing the amount of repeated code.
Add the capability to pack TLVs with TAG=2 (offset from first address)
Packs the TLV.length differently according to whether or not Aerial is in use ( for Aerial TLV.length is 16-bit, for OAI is 32-bit )
Add nr_fapi_p7 library to NFAPI_USER_LIB for access to utility functions
Change message handlers to use the utility functions to copy and properly free the messages
Change the SRS handler to call the handler for the measurements instead of trying to copy to RC.gNB[0], which does not exist
Change nfapi_nr_p7_message_unpack to not allocate unneeded memory
