CUDA toolkits since at least CUDA 4.0 have not supported an ability to run cuda code without a GPU.
If you simply want to compile code, refer to this question.
If you want to run CUDA codes compiled with CUDA 5.5, you will need a CUDA capable GPU.
If you're willing to use older CUDA toolkits, you could install one of the various emulators, such as this one.
Or you could install a very old (e.g. ~ CUDA 3.0) cuda toolkit that had the ability to run CUDA codes on the CPU.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…