add ORAN FHI Tutorial

doc/ORAN_FHI7.2_Tutorial.md

+**Table of Contents**
+
+## Prerequisites to run Platforms
+
+* DPDK (Data Plane Development Kit)
+
+  Download DPDK version 20.05 (https://core.dpdk.org/download/)
+
+  Compile DPDK 
+
+```
+tar xJf dpdk-<version>.tar.xz
+cd dpdk-<version>
+
+meson build
+cd build
+sudo ninja
+sudo ninja install
+
+make install T=x86_64-native-linuxapp-gcc
+```
+
+* Setup Configuration 
+
+  https://docs.o-ran-sc.org/projects/o-ran-sc-o-du-phy/en/latest/Setup-Configuration_fh.html
+
+* PTP configuration
+
+  https://docs.o-ran-sc.org/projects/o-ran-sc-o-du-phy/en/latest/PTP-configuration_fh.html
+
+* Bind devices 
+```
+sudo modprobe vfio_pci
+sudo /usr/local/bin/dpdk-devbind.py --bind vfio-pci 51:0e.0
+sudo /usr/local/bin/dpdk-devbind.py --bind vfio-pci 51:0e.1
+```
+
+## ORAN Fronthaul Library 
+
+  To get the ORAN FHI library and installation, follow the instructions
+
+ * Download O-RAN FHI PHY library
+ 
+```
+git clone https://gerrit.o-ran-sc.org/r/o-du/phy.git
+cd phy
+git checkout oran_release_bronze_v1.1
+```
+
+ * Apply patches (available in oai_folder/cmake_targets/tools/oran_fhi_integration_patches): 
+    
+```
+git apply oran-fhi-1-compile-libxran-using-gcc-and-disable-avx512.patch
+git apply oran-fhi-2-return-correct-slot_id.patch
+git apply oran-fhi-3-disable-pkt-validate-at-process_mbuf.patch
+git apply oran-fhi-4-process_all_rx_ring.patch
+```
+
+ * Set up the environment (change the path if you use different folders)
+   
+```
+export XRAN_LIB_DIR=~/phy/fhi_lib/lib/build
+export XRAN_DIR=~//phy/fhi_lib
+export RTE_SDK=~/dpdk-20.05
+export RTE_TARGET=x86_64-native-linuxapp-gcc
+export RTE_INCLUDE=${RTE_SDK}/${RTE_TARGET}/include
+```
+
+ * Compile phy/fhi_lib:
+   
+```
+./phy/fhi_lib/build.sh
+```
+
+## OAI-FHI Build and Compilation 
+
+```
+git clone https://gitlab.eurecom.fr/oai/openairinterface5g.git
+cd openairinterface5g
+git checkout develop
+source oaienv
+cd cmake_targets
+./build_oai --gNB --ninja -t oran_fhlib_5g (Add, -I as well if it is first time to use for external dependencies)
+```
+
+## Run OAI with ORAN FHI config 
+
+   ```
+   cd ran_build/build
+   cp ../../tools/oran_fhi_integration_patches/conf.json .
+   ```
+ * Change to MAC address of DU/RU and PCI address of your setup in conf.json
+
+```
+sudo ./nr-softmodem -O ../../../targets/PROJECTS/GENERIC-NR-5GC/CONF/oran_fh.conf --sa --reorder-thread-disable 1
+```
+
+