AM623: MCASP register memory space can not access in application layer

Part Number: AM623
Other Parts Discussed in Thread: SK-AM62-LP

Tool/software:

Hi  

I use the tool  devmem2  to read the MCASP register value, but it will core dumped. 

but when read UART register memory, it is success

Is there any limit for MCASP , please help check