While we tested the Intel HD Graphics GPU, most of the newer GL-based features and filters including OCL support won't work on that device. Some of those features might work on the HD 3000 depending on how much VRAM is available to the GPU.
As Chris stated above, for PS CS6 OCL support we run a quick test to ensure that the GPU can handle our code. If it fails, we disable OCL support in prefs. My guess is that your specific GPU is failing that test.
Out of curiosity, why is Memory Size being reported as 0MB above? That might have something to do with what you're seeing. What does PS report the total VRAM to be (you can check in PS Help > System Info for this data)?
We only enabled OpenCL for the Intel Sandy Bridge and Ivy Bridge (HD 3000 and HD 4000) series GPUs. Older Intel HD gpus (like yours) will support some GL functionality in PS CS6, but OCL isn't supported.