Any MRAM Simulation softwares??

Kind an old reply on this post, but anyway. I don't think that "Any MRAM Simulation software" exists. MRAM is very complex thingy and each company/research group writes its own software in their research. And btw, there are different types of MRAM... Which one you are interested in?

Assuming that you mean "micromagnetic simulation software", there is a freeware OOMMF package (developed by NIST) which can be used to simulate simple nano-sized structures such as thin films with predefined magnetic properties and finite geometry. By using the art of TCL scripting language and powerfull enough computer platform one can simulate the magnetics of spin-flop tunnel junctions for example, which are used as a base for toggle MRAM (That I was doing during my PhD work... ;-)