This command creates the `libldpc_cl.so` shared library. To perform this build successfully, only the OpenCL header `(/usr/include/CL/opencl.h)` and library `(/usr/lib/x86_64-linux-gnu/libOpenCL.so)`are required, they implement OpenCL API support which is not hardware dependent.
```
Scanning dependencies of target nrLDPC_decoder_kernels_CL
Built target nrLDPC_decoder_kernels_CL
Scanning dependencies of target ldpc_cl
Building C object CMakeFiles/ldpc_cl.dir/usr/local/oai/oai-develop/openairinterface5g/openair1/PHY/CODING/nrLDPC_decoder/nrLDPC_decoder_CL.c.o
In file included from /usr/include/CL/cl.h:32,
from /usr/include/CL/opencl.h:38,
from /usr/local/oai/oai-develop/openairinterface5g/openair1/PHY/CODING/nrLDPC_decoder/nrLDPC_decoder_CL.c:49:
/usr/include/CL/cl_version.h:34:9: note: #pragma message: cl_version.h: CL_TARGET_OPENCL_VERSION is not defined. Defaulting to 220 (OpenCL 2.2)
#pragma message("cl_version.h: CL_TARGET_OPENCL_VERSION is not defined. Defaulting to 220 (OpenCL 2.2)")
^~~~~~~
Building C object CMakeFiles/ldpc_cl.dir/usr/local/oai/oai-develop/openairinterface5g/openair1/PHY/CODING/nrLDPC_encoder/ldpc_encoder_optim8segmulti.c.o
Linking C shared module libldpc_cl.so
Built target ldpc_cl
```
At runtime, to successfully use hardware acceleration via OpenCL, you need to install vendor specific packages which deliver the required drivers and tools to make use of their GPU (Nvidia, Intel...) , fpga (Xilinx, Intel) or CPU (Intel, AMD, ARM...) through OpenCL.
`./nr-softmodem -O libconfig:gnb.band78.sa.fr1.106PRB.usrpb210.conf:dbgl5 --rfsim --rfsimulator.serveraddr server --sa --log_config.gtpu_log_level info --loader.ldpc.shlibversion _cl`
A mechanism to select ldpc implementation is also available in the `ldpctest` phy simulator via the `-v`option, which can be used to specify the version of the ldpc shared library to be used.
...
...
@@ -103,7 +124,9 @@ A mechanism to select ldpc implementation is also available in the `ldpctest` ph
Loading libldpc_cuda.so, the cuda implementation of the ldpc decoder:
```$ ./ldpctest -v _cuda
```
$ ./ldpctest -v _cuda
ldpctest -v _cuda
Initializing random number generator, seed 0
block length 8448:
n_trials 1:
...
...
@@ -119,18 +142,16 @@ log init done
[CONFIG] loader.ldpc: 1/2 parameters successfully set