Can I implement a four nios core system?

hello everyone!I am a new guy from china I am doing work related to multiple NIOS II cores. I have learned something from the document of both Nios and NiosII. I want to build a sopc system with at least 4 cpus of smp structure. I also want to implement a operation system base on uC/OS to support it.But I still wonder before I do it. Can I succeed?

Can anybody give some comment on it?

what I am still not sure now is:

1.How can I fulfil a inter-processor-interrupt among NiosII processors ,inter-processor-interrupt is useful to operation system.

2.How can I insure the consistency of the caches of different NiosII processors?

3.How can I dispatch the outer interrupt among NiosII processors?

Thanks for your help!