title: OpenCL doesn't detect GPU
body: <p>I installed AMD APP SDK and here my problem. The OpenCL samples do not detect the GPU. HelloWorld give me this:</p>
  
  <pre><code>[thomas@Clemence:/opt/AMDAPP/samples/opencl/bin/x86_64]$ ./HelloWorld
  No GPU device available.
  Choose CPU as default device.
  input string:
  GdkknVnqkc
  
  output string:
  HelloWorld
  Passed!
  </code></pre>
  
  <p>And here the clinfo output</p>
  
  <pre><code>[thomas@Clemence:~/Documents/radeontop]$ clinfo
  Number of platforms:                 1
  Platform Profile:                FULL_PROFILE
  Platform Version:                OpenCL 1.2 AMD-APP (1214.3)
  Platform Name:               AMD Accelerated Parallel Processing
  Platform Vendor:                 Advanced Micro Devices, Inc.
  Platform Extensions:                 cl_khr_icd cl_amd_event_callback  cl_amd_offline_devices
  
  
  Platform Name:               AMD Accelerated Parallel Processing
  Number of devices:               1
  Device Type:                     CL_DEVICE_TYPE_CPU
  Device ID:                   4098
  Board name:                  
  Max compute units:               8
  Max work items dimensions:           3
  Max work items[0]:               1024
  Max work items[1]:               1024
  Max work items[2]:               1024
  Max work group size:                 1024
  Preferred vector width char:             16
  Preferred vector width short:            8
  Preferred vector width int:          4
  Preferred vector width long:             2
  Preferred vector width float:            8
  Preferred vector width double:       4
  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:                 3633Mhz
  Address bits:                    64
  Max memory allocation:           4182872064
  Image support:               Yes
  Max number of images read arguments:         128
  Max number of images write arguments:        8
  Max image 2D width:              8192
  Max image 2D height:                 8192
  Max image 3D width:              2048
  Max image 3D height:                 2048
  Max image 3D depth:              2048
  Max samplers within kernel:          16
  Max size of kernel argument:             4096
  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:               Yes
  Round to +ve and infinity:           Yes
  IEEE754-2008 fused multiply-add:         Yes
  Cache type:                  Read/Write
  Cache line size:                 64
  Cache size:                  32768
  Global memory size:              16731488256
  Constant buffer size:                65536
  Max number of constant args:             8
  Local memory type:               Global
  Local memory size:               32768
  Kernel Preferred work group size multiple:   1
  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:                No
  Profiling :                  Yes
  Platform ID:                     0x00007f4ef63f0fc0
  Name:                        Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz
  Vendor:                  GenuineIntel
  Device OpenCL C version:             OpenCL C 1.2 
  Driver version:              1214.3 (sse2,avx)
  Profile:                     FULL_PROFILE
  Version:                     OpenCL 1.2 AMD-APP (1214.3)
  Extensions:                  cl_khr_fp64 cl_amd_fp64 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_int64_base_atomics cl_khr_int64_extended_atomics cl_khr_3d_image_writes cl_khr_byte_addressable_store cl_khr_gl_sharing cl_ext_device_fission cl_amd_device_attribute_query cl_amd_vec3 cl_amd_printf cl_amd_media_ops cl_amd_media_ops2 cl_amd_popcnt 
  </code></pre>
  
  <p>What should I do in order to have access to the GPU? Thanks in advance.
  I'm working on Ubuntu 14.04.3 LTS Trusty Kernel 3.9</p>
  
  <p>here my graphics card:</p>
  
  <pre><code>[thomas@elsa:~]$ lspci | grep -i --color 'vga'
  00:02.0 VGA compatible controller: Intel Corporation Xeon E3-1200 v3/4th 
  Gen Core Processor Integrated Graphics Controller (rev 06)
  01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] 
  Oland XT [Radeon HD 8670 / R7 250/350]
  </code></pre>