Add configurable values of NR RLC and NR PDCP to the configuration file
This is for the gNB (the UE gets the values from the gNB).
The physical simulators were also adapted (we put the previously
hardcoded values that were everywhere in the code into the simulators
themselves). I don't think we need to have those values configurable for
the simulators, but I can study the possibility to add this if someone
tells me it's important (if not important I prefer not to do it, I am
not sure if it is trivial to do or not).
according to TS 38.331, RRCReconfiguration messages can be carried
in a container by different RRC messages, e.g. HandoverPreparationInformation,
HandoverCommand, RRCResume etc.. therefore before the introduction of new
RRCReconfiguration messages, e.g. for handover, a new design seems to be necessary
in order to improve modularity and maintainability of the code.
The goal of this commit is to make the generation of RRCReconfiguration
messages more modular by (1) preparing the RRCReconfiguration parameters
data in RRC (2) pass it to ASN1 for IEs allocation (3) encode to buffer
The following changes are introduced:
(1) introduce struct nr_rrc_reconfig_param_t to store the RRC parameters relevant
to encode the RRCReconfiguration IEs
(2) add RRC function get_RRCReconfiguration_params to fetch nr_rrc_reconfig_param_t
data from the UE context and
(3) pass it to the ASN1 encoder, e.g. do_RRCReconfiguration
(4) add a function build_RRCReconfiguration_IEs to allocate memory and build the
ASN1 NR_RRCReconfiguration_IEs_t and
(5) adopt it in do_RRCReconfiguration
(4) add free_RRCReconfiguration_params for memory management of nr_rrc_reconfig_param_t data
(6) add test for rrc_reconfiguration
get_RRCReconfiguration_params:
This function prepares RRCReconfigurationParams for RRC encoding.
Motivation of this change: depending on the RRCReconfiguration
message to be encoded, the ownership of ASN1 memory allocation
should belong to the ASN1 layer, therefore this function is
preparing the nr_rrc_reconfig_param_t data to pass to the
ASN1 encoder to build the ASN1 message and encode to buffer
The function is preparing the params for the IEs that are
either mandatory or shared among different RRC messages.
Specific fields that depend on the message to be encoded are then
added afterwards in the caller. The input param to indicate
re-establishment has been split between SRBs and DRBs, since
depending on the scenario the PDCP re-establishment can vary.
This will be addressed in a later commit.
This function is also handling xid.
build_RRCReconfiguration_IE:
The long term goal is to transfer ownership of memory allocation in ASN1 encoding to
build_RRCReconfiguration_IE, then by calling ASN_STRUCT_FREE_CONTENTS_ONLY
on dl_dcch_msg, all IEs allocated in the context are freed after encoding to buffer.
In the long term, createDRBlist, createSRBlist can also be brought into the context
of build_RRCReconfiguration_IEs and free the ASN1 structure after encoding.
This improves maintability and helps preventing memory leaks.
Currently, what is not allocated in the context, is nulled and freed outside.
free_RRCReconfiguration_params:
this function frees memory allocated to build the nr_rrc_reconfig_param_t data,
including the NR_DRB_ToAddModList_t and NR_SRB_ToAddModList_t. The function
freeDRBlist has been removed since no longer necessary.
dedicated_NAS_msg_list:
dedicated_NAS_msg_list handling has also been refactored, by:
(1) fetch the NAS PDUs from the UE context in get_RRCReconfiguration_params,
which translates to (2) passing an array of dedicatedNAS-MessageList + size
to the ASN1 encoding function where (3) the ASN1 encoding logic for the
dedicated_NAS_msg_list IE has been moved
Note, 3GPP TS 38.331:
dedicatedNAS-MessageList: SEQUENCE (SIZE(1..maxDRB)) OF DedicatedNAS-Message
- 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)
One of the next commits moves nr_rrc_config.c "down to" the MAC/DU. The
BearerConfig functions are only used at the DU, so move them here in the
corresponding file.
Add functionality to trigger the addition of a new RRC UE context (in
the CU) for NSA modes, using F1. This commit makes do-ra and phy-test
modes work. "True" NSA will work in the next commit, which also sends
the X2 addition request answer message.
* Use the 5G-S-TMSI stored in RRC to be used as UE identity
* Use 5G-S-TMSI part 1 in RRCSetupRequest encoding (TS 38.331 clause 5.3.3.3)
* Set the ng-5G-S-TMSI-Value in RRCSetupComplete to ng-5G-S-TMSI-Part2 (5.3.3.4 of 3GPP TS 38.331)
* current and only scenario: RRCSetup is received in response to an RRCSetupRequest
HandoverPreparationInformation will be used in the follow-up commit to
trigger a handover.
Co-authored-by: batuhanduyuler <batuhan.duyuler@firecell.io>
Co-authored-by: rmagueta <rmagueta@allbesmart.pt>
Neighbor configuration can be given by gNB.conf
get_MeasConfig function is extended as it will prepare A2 / A3 Report
Configs. Single Meas Obj is used for all.
rrc_gNB_process_MeasurementReport function is extended to process A2 /
A3 measurement events. helper functions are written to fetch neighbour
cell informations from sequence containers.
(get_neighbour_cell_information, get_neighbour_config)
The starting point was the function do_NR_DLInformationTransfer() which
may deal with more than 256 bytes.
Then why not cleanup all the functions in the same file.
(And do a bit of formattting fixing while we're here.)
Then cleanup the callers of those functions.
Then, because of do_SIB23_NR() let's also cleanup in some
structures.
Not all the codebase was cleaned up, there surely remain some uint8_t
(and char/short/uint16_t) which are wrong.
The UE should measure on the SSB, otherwise it does not see anything.
Hence, this commit fixes the meas-config to request the UE to measure
on the right frequency.
!SIB1 is not correctly filled! This commit does not work with COTS UEs!
The next commit fixes this.
- Move radio config (e.g., minRXTXTIME, SIB1 TDA, do_SRS, etc) down to
MAC.
- Some parameters in MAC are redundant: delete them.
- Remove call to nr_mac_config_scc() from RRC and simulators, the MAC
initialization routine calls it implicitly
Note: the reestablishment is broken, and a later commit fixes it.
The ServingCellConfigCommon is an inherently radio-related
configuration. As such, it should be handled by the DU, not the CU.
Therefore, move it "down" to the MAC.
fill_default_secondaryCellGroup() is moved to nr_rrc_config.c.
Furthermore, the signature is changes to return the NR_CellGroupConfig
from the functions, instead of filling a pre-allocated structure (which
is, in all cases, allocated just before calling
fill_default_secondaryCellGroup().
There is a problem with this function: the function also fills the
ServingCellConfig (a parameter to this function). This behavior has not
been changed.
nr_DRB_preconfiguration() does a "pre-configuration" for the default DRB
for "noS1" mode, i.e., when there is no connection to core network. In
this case, there is no PDU session to be set up, and hence we need to
preconfigure the DRBs.
We replace this function with partially existing functions and a new
function fill_nr_noS1_bearer_config() which returns a bearer
configuration for the noS1 case, also better reflected in the function
name. It has also been moved to asn1_msg.c, away from the actual PDCP
layer.
- AssertFatal() in nr_rlc_srb0_recv_sdu() if the srb0 is not found
- do_RRCSetup() may return -1, handle it properly
- do_RRCReject() may return -1, handle it properly
- remove one switch in rrc_gNB_generate_RRCReject()
Robert Schmidt