MUSB OTG and DMA

Hello. 

I working on para-virtulisated MUSB linux's driver for microkernel OS. And i have problem with DMA mode of MUSB OTG driver. In PIO mode all things works good. But in DMA Mode nothing happens:

All things of USB works fine - i see new OTG device on HOST system, but data don't transfer - for example, if i do ping from host or from device - 0 packets sends. 

The main problem is - musbhdrc DMA irq never happens. I checked - dma_data correctly sets. Unfortunately Mentor didn't publish datasheets on internal of musb, so i can't check what the MUSB doing. 

So, my questions are:

1. Can you help me with datasheet on MUSB?

2. How DMA mode works on MUSB? Is it a part of MPU DMA engine? or something else? Why inside musbhdrc don't use a dma_pool and other DMA stuff?