Enable OpenCL over multiple platforms in Linux? How to proceed with ICD files?

Question

Details

What drivers/packages do I have to install in order to enable OpenCL over multiple platforms: CPU (Intel), Integrated GPU (Intel), Dedicated GPU (NVIDIA)?
It would be nice to have all platforms running OpenCL 1.2 or above

I know it is probably a simple fix, maybe just the right selection of libraries/SKDs, but I am having some trouble getting more them one platform to work.

Running ubuntu 14.04: I have a intel core I5 with the integrated intel graphics and a dedicated NVIDIA Geforce 710m board.

Resources I have used

https://wiki.tiker.net/OpenCLHowTo
Here (under Debian) it tells me that I only need:

Packages of ICD loaders: (you just need one of these)
Packages of ICDs
Package for headers

What I have already tried

Installed CUDA7.5 (yes for all)
- Had a black screen due drivers conflics
  - Resolved by uninstalling all nvidia drivers and installing 352
  - Still left Cuda SDK install
From: How to make OpenCL work on 14.10 + Nvidia 331.89 drivers?
- sudo apt-get install nvidia-331 nvidia-331-uvm nvidia-opencl-dev nvidia-modprobe
- Those packages downgraded my drivers to 331 and 340
Also from: How to make OpenCL work on 14.10 + Nvidia 331.89 drivers?
- Linked libraries with:
  - sudo ln -s /usr/include/nvidia-352/GL /usr/local/include
  - sudo ln -s /usr/lib/x86_64-linux-gnu/libOpenCL.so.1 /usr/local/lib/libOpenCL.so
- OpenCL 1.1 worked for NVIDIA GPU
- Could not get OpenCL 1.2, thus decided to uninstall 331 and 340 and install again 352
Installed 352 (again)
- OpenCL 1.1 stopped working for NVIDIA GPU (and still does not work)
Installed Intel opencl_runtime_14.2_x64_4.5.0.8.tgz
- Created a simbolic link to intel ICD with:
  - sudo ln -s /opt/intel/opencl-1.2-4.5.0.8/etc/intel64.icd
- OpenCL 1.2 worked for CPU (and still works)
Installed clinfo sudo apt-get install clinfo
- only intel CPU platform is detected
Tried to install several different NVIDIA packages to get NVIDIA GPU work again but had no luck with that

Installed packages and some information:

ICD in Vendors?

ls -l /etc/OpenCL/vendors/
total 4
-rw-r--r-- 1 root root 15 Out 22  2015 Altera.icd
lrwxrwxrwx 1 root root 45 Abr 28 13:48 intel64.icd -> /opt/intel/opencl-1.2-4.5.0.8/etc/intel64.icd

Note the missing nvidia.icd

CL and GL - GL had a valid link... now is IN RED

ls -l /usr/local/include
total 4
lrwxrwxrwx 1 root root   31 Abr 28 12:48 CL -> /usr/local/cuda-7.5/include/CL/
lrwxrwxrwx 1 root root   26 Abr 27 11:44 GL -> /usr/include/nvidia-352/GL (IN RED COLOR - folder doesn't exist anymore)

.so Files

ls -l /usr/local/lib/ | grep CL
lrwxrwxrwx 1 root root    40 Abr 27 11:45 libOpenCL.so -> /usr/lib/x86_64-linux-gnu/libOpenCL.so.1

Installed packages

dpkg --get-selections | grep nvidia
nvidia-340                  deinstall
nvidia-352                  install
nvidia-libopencl1-340               deinstall
nvidia-libopencl1-340-updates           deinstall
nvidia-libopencl1-352               deinstall
nvidia-libopencl1-352-updates           install
nvidia-modprobe                 install
nvidia-opencl-icd-340               deinstall
nvidia-opencl-icd-352               deinstall
nvidia-prime                    install
nvidia-settings                 install


dpkg --get-selections | grep opencl
nvidia-libopencl1-340               deinstall
nvidia-libopencl1-340-updates           deinstall
nvidia-libopencl1-352               deinstall
nvidia-libopencl1-352-updates           install
nvidia-opencl-icd-340               deinstall
nvidia-opencl-icd-352               deinstall
ocl-icd-libopencl1:amd64            deinstall
ocl-icd-libopencl1:i386             deinstall
opencl-headers                  install
unity-scope-openclipart             install

clinfo

clinfo 
Number of platforms:                 1
  Platform Profile:              FULL_PROFILE
  Platform Version:              OpenCL 1.2 LINUX
  Platform Name:                 Intel(R) OpenCL
  Platform Vendor:               Intel(R) Corporation
  Platform Extensions:               cl_khr_icd cl_khr_global_int32_base_atomics cl_khr_global_int32_extended_atomics cl_khr_local_int32_base_atomics cl_khr_local_int32_extended_atomics cl_khr_byte_addressable_store cl_khr_spir cl_intel_exec_by_local_thread cl_khr_depth_images cl_khr_3d_image_writes cl_khr_fp64 


  Platform Name:                 Intel(R) OpenCL
Number of devices:               1
  Device Type:                   CL_DEVICE_TYPE_CPU
  Device ID:                     32902
  Max compute units:                 4
  Max work items dimensions:             3
    Max work items[0]:               8192
    Max work items[1]:               8192
    Max work items[2]:               8192
  Max work group size:               8192
  Preferred vector width char:           1
  Preferred vector width short:          1
  Preferred vector width int:            1
  Preferred vector width long:           1
  Preferred vector width float:          1
  Preferred vector width double:         1
  Native vector width char:          16
  Native vector width short:             8
  Native vector width int:           4
  Native vector width long:          2
  Native vector width float:             8
  Native vector width double:            4
  Max clock frequency:               1800Mhz
  Address bits:                  64
  Max memory allocation:             2040185856
  Image support:                 Yes
  Max number of images read arguments:       480
  Max number of images write arguments:      480
  Max image 2D width:                16384
  Max image 2D height:               16384
  Max image 3D width:                2048
  Max image 3D height:               2048
  Max image 3D depth:                2048
  Max samplers within kernel:            480
  Max size of kernel argument:           3840
  Alignment (bits) of base address:      1024
  Minimum alignment (bytes) for any datatype:    128
  Single precision floating point capability
    Denorms:                     Yes
    Quiet NaNs:                  Yes
    Round to nearest even:           Yes
    Round to zero:               No
    Round to +ve and infinity:           No
    IEEE754-2008 fused multiply-add:         No
  Cache type:                    Read/Write
  Cache line size:               64
  Cache size:                    262144
  Global memory size:                8160743424
  Constant buffer size:              131072
  Max number of constant args:           480
  Local memory type:                 Global
  Local memory size:                 32768
  Error correction support:          0
  Unified memory for Host and Device:        1
  Profiling timer resolution:            1
  Device endianess:              Little
  Available:                     Yes
  Compiler available:                Yes
  Execution capabilities:                
    Execute OpenCL kernels:          Yes
    Execute native function:             Yes
  Queue properties:              
    Out-of-Order:                Yes
    Profiling :                  Yes
  Platform ID:                   0x1659390
  Name:                             Intel(R) Core(TM) i5-3337U CPU @ 1.80GHz
  Vendor:                    Intel(R) Corporation
  Device OpenCL C version:           OpenCL C 1.2 
  Driver version:                1.2.0.8
  Profile:                   FULL_PROFILE
  Version:                   OpenCL 1.2 (Build 8)
  Extensions:                    cl_khr_icd cl_khr_global_int32_base_atomics cl_khr_global_int32_extended_atomics cl_khr_local_int32_base_atomics cl_khr_local_int32_extended_atomics cl_khr_byte_addressable_store cl_khr_spir cl_intel_exec_by_local_thread cl_khr_depth_images cl_khr_3d_image_writes cl_khr_fp64

So...

How can I get NVIDIA gpu to also show up as a OPENCL 1.2 (or higher) platform? How about the integrated intel graphics?
Would AMD libraries work with my hardware?
Why most of the nvidia packages are marked as deinstall?

ps.: I do have the NVIDIA board running sudo prime-select nvidia — nico
ps.: I do not have an *.icd file in \usr\share\nvidia-352\ . But I had before something linked to nvidia-331 in the \etc\OpenCL\vendors folder. Which may have enabled me to use OpenCL 1.1 — nico

nico nico · Accepted Answer · 2016-05-01T05:30:08

As mentioned before, three things are necessary:

From https://wiki.tiker.net/OpenCLHowTo

Packages of ICD loaders: (you just need one of these)
Packages of ICDs
Package for headers

Thus for an Intel CPU and a NVIDIA GPU

Packages of ICD loaders:
- ocl-icd-libopencl1
Packages of ICDs
- Installed Intel OpenCL runtime
- nvidia-opencl-icd-352
Package for headers
- opencl-headers

However, to get it to work, it is necessary to make sure the packages are marked as install by dpkg --get-selections | grep opencl

sudo apt-get install --reinstall nvidia-opencl-icd-352 opencl-headers ocl-icd-libopencl1

On top of that, you must make sure that intel64.icd and nvidia.icd are in /etc/OpenCL/vendors (ls -l /etc/OpenCL/vendors).

That said, I had to link intel64.icd with:

cd /etc/OpenCL/vendors/
sudo ln -s /opt/intel/opencl-1.2-X.X.X.X/etc/intel64.icd

And, since nvidia.icd was not in the folder (even after the installation of the right package) I had to extract it and manually move from the deb package

dpkg -x /var/cache/apt/archives/nvidia-opencl-icd-352_352.63-0ubuntu0.14.04.1_amd64.deb ~/tempfolder
sudo mv ~/tempfolder/etc/OpenCL/vendors/nvidia.icd /etc/OpenCL/vendors/nvidia.icd
rm -r ~/tempfolder

Finally, make sure nvidia is the active GPU

sudo prime-select nvidia
sudo reboot -r now

Install and execute clinfo and both platforms should show-up.

clinfo 
Number of platforms:                 2
  Platform Profile:              FULL_PROFILE
  Platform Version:              OpenCL 1.2 CUDA 7.5.23
  Platform Name:                 NVIDIA CUDA
  Platform Vendor:               NVIDIA Corporation
  Platform Extensions:               cl_khr_byte_addressable_store cl_khr_icd cl_khr_gl_sharing cl_nv_compiler_options cl_nv_device_attribute_query cl_nv_pragma_unroll cl_nv_copy_opts 
  Platform Profile:              FULL_PROFILE
  Platform Version:              OpenCL 1.2 LINUX
  Platform Name:                 Intel(R) OpenCL
  Platform Vendor:               Intel(R) Corporation
  Platform Extensions:               cl_khr_icd cl_khr_global_int32_base_atomics cl_khr_global_int32_extended_atomics cl_khr_local_int32_base_atomics cl_khr_local_int32_extended_atomics cl_khr_byte_addressable_store cl_khr_spir cl_intel_exec_by_local_thread cl_khr_depth_images cl_khr_3d_image_writes cl_khr_fp64