Refactor F1 setup processing to create and manage cell containers during DU
initialization, establishing the foundation for multi-cell architecture where
cells are managed independently from DUs.
Why: Cell information is currently tied to F1AP structures (f1ap_served_cell_info_t),
which complicates multi-cell support. Introducing cell containers at F1 setup
decouples RRC cell management from F1AP and allows cells to be managed
independently while keeping existing code paths working.
Key changes:
1. Cell container creation (cp_f1_served_cell_info_to_cell):
New helper copying F1AP served cell info into nr_rrc_cell_container_t (cell_id,
pci, plmn, tac, TDD/FDD frequency info). Extracts and stores MTC in the cell.
2. Function signature updates:
get_cell_neighbour_list() and label_intra_frequency_neighbours() now take
nr_rrc_cell_container_t* and use cell->info; improved logging (cell_id, PCI,
SSB ARFCN).
3. valid_du_in_neighbour_configs:
Removed ssb_arfcn parameter; MTC is extracted and freed inside the function.
4. F1 Setup (rrc_gNB_process_f1_setup_req):
Initialize DU cell tree (RB_INIT(&du->cells)). Populate DU-only fields
(gNB_DU_id, gNB_DU_name, rrc_ver).
Flow:
- create cell with cp_f1_served_cell_info_to_cell
- add to global tree via rrc_add_cell()
- add DU via rrc_add_du()
- attach cell to DU with rrc_add_cell_to_du().
Store MIB/SIB1/MTC in cell.
Use cell container for neighbour labeling and SIB encoding.
5. Duplicate cell detection:
Use rrc_add_cell() for global cell tree insert; collision return indicates
duplicate cell_id. Clearer error messages for Cell ID vs PCI conflicts.
Use F1AP_CauseRadioNetwork_cell_not_available for cell conflicts.
6. DU configuration update:
Use get_cell_by_cell_id() to find cell, check assoc_id, pass cell container
to label_intra_frequency_neighbours().
7. DU disconnection:
Use rrc_cleanup_du() to remove cells from global tree and free resources;
logging uses DU fields (gNB_DU_id, gNB_DU_name).
8. Global cell tree:
Initialize rrc->cells in openair_rrc_gNB_configuration().
Backward compatibility: setup_req still built via cp_f1ap_setup_request();
du->mib, du->sib1, du->mtc remain set (shared with cell container).
Guido Casati
95d35b9b7d