A. Directory Structure :
------------------------
1. l2/build/ : contains files required to compile the code
   a. common : contains individual module's makefile
   b. odu    : contains main makefile to generate an executable binary
   c. scripts: contains scripts for logging, installing netconf libraries and starting netopeer server
   d. config : contains the configuration files
   e. yang   : contains the YANG modules

2. l2/docs/  : contains README and other configuration files for building docs
	
3. l2/src/ : contains layer specific source code
   a. 5gnrmac  : MAC source code
   b. 5gnrrlc  : RLC source code
   c. cm       : common, environment and interface files
   d. cu_stub  : Stub code for CU
   e. du_app   : DU application and F1 code 
   f. mt       : wrapper functions over OS
   g. phy_stub : Stub code for Physical layer
   h. rlog     : logging module
   i. o1       : o1 module


B. Pre-requisite for Compilation :
----------------------------------
1. Linux 32-bit/64-bit machine
2. GCC version 4.6.3 and above
3. Install LKSCTP
   a. On Ubuntu : sudo apt-get install -y libsctp-dev
   b. On CentOS : sudo yum install -y lksctp-tools-devel
4. Install PCAP:
   a. On ubuntu : sudo apt-get install -y libpcap-dev
   b. On CentOS : sudo yum install -y libpcap-devel


C. Pre-requisite for O1 Interface (Required only if run with O1 interface enabled) 
-----------------------------------------------------------------------------------
1. Setup netconf server

	Create new netconf user (login with root user and run following commands)
	$adduser --system netconf && \
        echo "netconf:netconf!" | chpasswd

	$mkdir -p /home/netconf/.ssh && \
	ssh-keygen -A && \
	ssh-keygen -t dsa -P '' -f /home/netconf/.ssh/id_dsa && \
        cat /home/netconf/.ssh/id_dsa.pub > /home/netconf/.ssh/authorized_keys
	Install netconf packages. 
	$cd l2/build/scripts
	$chmod +x install_lib_O1.sh
	$ ./install_lib_O1.sh -c

2. Start Netopeer2-server:
   $cd l2/build/scripts
   $./netopeer-server.sh start

3. Install the yang modules
   $cd l2/build/yang
   $sysrepoctl -i o-ran-sc-odu-alarm-v1.yang
   $sysrepoctl -i o-ran-sc-odu-interface-v1.yang

4. Configure the startup IP and Port configurations for DU, CU and RIC

   $cd l2/build/config

   Open the startup_config.xml and edit the desired IP and Port for CU, DU and RIC.
   Then load the configuration in the sysrepo running datastore using the command below

   $sysrepocfg --import=startup_config.xml --datastore running --module  o-ran-sc-odu-interface-v1 

5. Configure the netconf server details for VES PNF Event

   $cd l2/build/config

   Open the netconfConfig.xml and edit the desired MAC address, IP, Port, Username and Password for VES PNF Registration.

6. Configure the VES server details to send VES Events

   $cd l2/build/config

   Open the vesConfig.xml and edit the desired IP, Port, Username and Password to send VES Event.


D. How to Clean and Build:
--------------------------
1. Build commands:
   a. odu       - Builds all components of ODU
   b. cu_stub   - Builds all CU Stub
   c. ric_stub  - Builds all RIC_Stub
   d. clean_odu - clean up ODU
   e. clean_cu  - clean up CU Stub
   f. clean_ric - clean up RIC Stub
   g. clean_all - cleanup everything
   h. options:
      i.   MACHINE=BIT64/BIT32 - Specify underlying machine type. Default is BIT32
      ii.  NODE=TEST_STUB      - Specify if it is a test node. Mandatory for cu_stub/ric_stub. Must not be used for odu
      iii. MODE=FDD/TDD        - Specify duplex mode. Default is FDD
      iv.  PHY=INTEL_L1        - Specify type of phy. If not specified, PHY stub is used
      v.   PHY_MODE=TIMER      - Specify mode of phy. Used only if PHY=INTEL_L1. Default is radio mode
      vi.  O1_ENABLE=YES       - Specify if O1 interface is enabled. If not specified, it is disabled 

2. Building ODU binary:
   a. Build folder
         cd l2/build/odu
   b. Building ODU binary
         make odu MACHINE=<refer section D.1.h>  MODE=<refer section D.1.h>
   c. Cleaning ODU binary
         make clean_odu MACHINE=<refer section D.1.h> MODE=<refer section D.1.h>

3. Building CU Stub binary:
   a. Build folder
         cd l2/build/odu
   b. Building CU Stub binary
         make cu_stub NODE=<refer section D.1.h> MACHINE=<refer section D.1.h> MODE=<refer section D.1.h>
   c. Cleaning CU Stub binary
         make clean_cu NODE=<refer section D.1.h> MACHINE=<refer section D.1.h> MODE=<refer section D.1.h>

4. Building RIC Stub binary:
   a. Build folder
         cd l2/build/odu
   b. Building RIC Stub binary
         make ric_stub NODE=<refer section D.1.h> MACHINE=<refer section D.1.h> MODE=<refer section D.1.h>
   c. Cleaning RIC Stub binary
         make clean_ric NODE=<refer section D.1.h> MACHINE=<refer section D.1.h> MODE=<refer section D.1.h>

5. Cleaning ODU, CU Stub and RIC Stub:
      make clean_all


E. How to Clean and Build with O1 interface enabled (Requires pre-requisite steps in section C)
------------------------------------------------------------------------------------------------

1. Building ODU binary:
   a. Build folder
         cd l2/build/odu
   b. Building ODU binary
         make odu MACHINE=<refer section D.1.h> MODE=<refer section D.1.h> O1_ENABLE=<refer section D.1.h>
   c. Cleaning ODU binary
         make clean_odu MACHINE=<refer section D.1.h> MODE=<refer section D.1.h> O1_ENABLE=<refer section D.1.h>

2. Building CU Stub binary:
   a. Build folder
         cd l2/build/odu
   b. Building CU Stub binary
         make cu_stub NODE=<refer section D.1.h> MACHINE=<refer section D.1.h> MODE=<refer section D.1.h> O1_ENABLE=<refer section D.1.h>
   c. Cleaning CU Stub binary
         make clean_cu NODE=<refer section D.1.h> MACHINE=<refer section D.1.h> MODE=<refer section D.1.h> O1_ENABLE=<refer section D.1.h>

3. Building RIC Stub binary:
   a. Build folder
         cd l2/build/odu
   b. Building RIC Stub binary
         make ric_stub NODE=<refer section D.1.h> MACHINE=<refer section D.1.h> MODE=<refer section D.1.h> O1_ENABLE=<refer section D.1.h>
   c. Cleaning RIC Stub binary
         make clean_ric NODE=<refer section D.1.h> MACHINE=<refer section D.1.h> MODE=<refer section D.1.h> O1_ENABLE=<refer section D.1.h>

4. Cleaning ODU, CU Stub and RIC Stub:
      make clean_all


F. How to execute:
------------------
1. Assign virtual IP addresses as follows:
   a. ifconfig <interface name>:ODU "192.168.130.81"
   b. ifconfig <interface name>:CU_STUB "192.168.130.82"
   c. ifconfig <interface name>:RIC_STUB "192.168.130.80"

PS: If O1 interface is enabled, IP should match those configured in step C.4.

2. Execute CU Stub:
   a. CU execution folder:
      	cd l2/bin/cu_stub
   b. Run CU Stub binary:
      	./cu_stub

3. Execute RIC Stub:
   a. RIC execution folder:
      	cd l2/bin/ric_stub
   b. Run RIC Stub binary:
      	./ric_stub

4. Execute DU:
   a. DU execution folder:
      	cd l2/bin/odu
   b. Run ODU binary:
      	./odu

PS: CU stub and RIC stub must be run (in no particular sequence) before ODU


G. How to test with Intel L1:
-----------------------------

I. Compilation
   1. Build ODU :
      a. Create folder l2/src/wls_lib. Copy wls_lib.h from <intel_directory>/phy/wls_lib/ to l2/src/wls_lib.
      b. Create folder l2/src/dpdk_lib. Copy following files from <intel_directory>/dpdk-19.11/x86_64-native-linuxapp-gcc/include/ to l2/sr        c/dpdk_lib.
                rte_branch_prediction.h
                rte_common.h
                rte_config.h
                rte_dev.h
                rte_log.h
                rte_pci_dev_feature_defs.h
                rte_bus.h
                rte_compat.h
                rte_debug.h
                rte_eal.h
                rte_os.h
                rte_per_lcore.h
      c. Build folder
                cd l2/build/odu
      d. Build ODU Binary:
		          make odu PHY=<refer section D.1.h> PHY_MODE=<refer section D.1.h> MACHINE=<refer section D.1.h> MODE=<refer section D.1.h>

   2. Build CU Stub and RIC Stub:
      a. Execute steps in sections D.3 and D.4

II. Execution
    1. Refer to below link for assumptions, dependencies, pre-requisites etc for ODU-Low execution
       https://docs.o-ran-sc.org/projects/o-ran-sc-o-du-phy/en/latest/

    2. Execute L1:
       a. Setup environment:
                cd <intel_directory>/phy/
                source ./setupenv.sh
       b. Run L1 binary :
                cd <intel_directory>/FlexRAN/l1/bin/nr5g/gnb/l1
                To run 
			i.  In timer mode : ./l1.sh -e
                	ii. In radio mode : ./l1.sh -xran
                L1 is up when console prints follow:

                   Non BBU threads in application
                   ===========================================================================================================
                   nr5g_gnb_phy2mac_api_proc_stats_thread: [PID:   8659] binding on [CPU  0] [PRIO:  0] [POLICY:  1]
                   wls_rx_handler (non-rt):                [PID:   8663] binding on [CPU  0]
                   ===========================================================================================================
                 
                   PHY>welcome to application console

    3. Execute FAPI Translator:
       a. Setup environment:
                cd <intel_directory>/phy/
                source ./setupenv.sh
       b. Run FAPI translator binary:
                cd <intel_directory>/phy/fapi_5g/bin/
                ./oran_5g_fapi --cfg=oran_5g_fapi.cfg

    4. Execute CU Stub and RIC Stub:
       a. Run steps in sections E.1-E.3

    5. Execute DU:
       a. DU execution folder
          	cd l2/bin/odu
       b. Export WLS library path
          	export LD_LIBRARY_PATH=<intel_directory>/phy/wls_lib/lib:$LD_LIBRARY_PATH
       c. Run ODU binary
          	./odu


H. How to execute the Health Check : get alarm-list
----------------------------------------------------
   
   Steps:

   1. Start Netconf netopeer client 
   
   2. Connect to the server with 

        user: netconf
        pwd:  netconf!

   3. Send a Netconf get request for alarms xpath

   Here are the steps as executed in the terminal 

      $netopeer2-cli
       > connect --login netconf
       Interactive SSH Authentication
       Type your password:
       Password:
       > get --filter-xpath /o-ran-sc-odu-alarm-v1:odu/alarms
       DATA
       <odu xmlns="urn:o-ran:odu:alarm:1.0">
         <alarms>
           <alarm>
             <alarm-id>1009</alarm-id>
             <alarm-text>cell id  [1] is up</alarm-text>
             <severity>2</severity>
             <status>Active</status>
             <additional-info>cell UP</additional-info>
           </alarm>
         </alarms>
       </odu>

   The XML output is a list of active alarms in the O-DU High system.