dm816x video m3 cache configure

How to set video m3's L2 cache mar on dm816x?How to set video m3's L2 to cache the DDR?(ps:I use ezsdk)

The following script doesn't work:

var Cache = xdc.useModule('ti.sysbios.family.arm.ducati.Cache');

Cache.MAR128_159 = 0xFFFFFFFF;  

Cache.MAR160_191 = 0xFFFFFFFF;