more enb interface comments

lib/include/srslte/interfaces/enb_interfaces.h

@@ -273,8 +273,17 @@ public:
   virtual void reset()                                                            = 0;
 
   /* Manages UE configuration context */
-  virtual int ue_cfg(uint16_t rnti, sched_interface::ue_cfg_t* cfg)                             = 0;
+  virtual int ue_cfg(uint16_t rnti, sched_interface::ue_cfg_t* cfg) = 0;
-  virtual int ue_rem(uint16_t rnti)                                                             = 0;
+  virtual int ue_rem(uint16_t rnti)                                 = 0;
+
+  /**
+   * Called after Msg3 reception to set the UE C-RNTI, resolve contention, and alter the UE's configuration in the
+   * scheduler and phy.
+   *
+   * @param temp_crnti temporary C-RNTI of the UE
+   * @param crnti chosen C-RNTI for the UE
+   * @param cfg new UE scheduler configuration
+   */
   virtual int ue_set_crnti(uint16_t temp_crnti, uint16_t crnti, sched_interface::ue_cfg_t* cfg) = 0;
 
   /* Manages UE bearers and associated configuration */
@@ -284,7 +293,10 @@ public:
   virtual void
   write_mcch(asn1::rrc::sib_type2_s* sib2, asn1::rrc::sib_type13_r9_s* sib13, asn1::rrc::mcch_msg_s* mcch) = 0;
 
-  /* Allocation of C-RNTI during HO */
+  /**
+   * Allocate a C-RNTI for a new user, without adding it to the phy layer and scheduler yet
+   * @return value of the allocated C-RNTI
+   */
   virtual uint16_t allocate_rnti() = 0;
 };
 

lib/include/srslte/interfaces/sched_interface.h

@@ -254,9 +254,27 @@ public:
   virtual uint32_t get_dl_buffer(uint16_t rnti) = 0;
 
   /******************* Scheduling Interface ***********************/
-  /* DL buffer status report */
+
+  /**
+   * Update the current RLC buffer state for a given user and bearer.
+   *
+   * @param rnti user rnti
+   * @param lc_id logical channel id for which the buffer update is concerned
+   * @param tx_queue number of pending bytes for new DL RLC transmissions
+   * @param retx_queue number of pending bytes concerning RLC retransmissions
+   * @return error code
+   */
   virtual int dl_rlc_buffer_state(uint16_t rnti, uint32_t lc_id, uint32_t tx_queue, uint32_t retx_queue) = 0;
-  virtual int dl_mac_buffer_state(uint16_t rnti, uint32_t ce_code, uint32_t nof_cmds)                    = 0;
+
+  /**
+   * Enqueue MAC CEs for DL transmission
+   *
+   * @param rnti user rnti
+   * @param ce_code lcid of the MAC CE
+   * @param nof_cmds how many repetitions of the same MAC CE should be scheduled
+   * @return error code
+   */
+  virtual int dl_mac_buffer_state(uint16_t rnti, uint32_t ce_code, uint32_t nof_cmds) = 0;
 
   /* DL information */
   virtual int dl_ack_info(uint32_t tti, uint16_t rnti, uint32_t enb_cc_idx, uint32_t tb_idx, bool ack) = 0;

srsenb/src/stack/rrc/rrc.cc

@@ -1643,6 +1643,7 @@ void rrc::ue::send_connection_setup(bool is_setup)
 
   // Configure MAC
   if (is_setup) {
+    // In case of RRC Connection Setup message (Msg4), we need to resolve the contention by sending a ConRes CE
     parent->mac->ue_set_crnti(rnti, rnti, &current_sched_ue_cfg);
   } else {
     parent->mac->ue_cfg(rnti, &current_sched_ue_cfg);