how can the dsp access peripherals?

Zhang,

I didn't understand the question clearly. I think you would like to know how to disable ARM accessing the peripherals that are access from DSP. Assuming that you are using Linux, you can disable the McBSP and I2C driver for the particular hardware instance in the kernel code to achieve this. 

thank you for your kind!

In my case , the dsp want to access some peripherals,Can the dsp access the peripherals directly without any config? I ever think if we didn't do some configs, only arm can access these peripherals.

Zhang,

I believe one can access most of the peripherals from DSP also.