RTOS/PROCESSOR-SDK-AM437X: GPMC access

Part Number:PROCESSOR-SDK-AM437X

Tool/software: TI-RTOS

I want to access the first address 0x1000000(physical address) on a SRAM chip(8bits/512KByte), CPU is the AM4376, and no OS(pdk_am437x_1_0_10).

If I disable all the MMU and cache, It can work(I can get the active chip select signal from the oscilloscope). but because of other requirements, I have to enable the MMU and cache, the code is:

    MMUConfigAndEnable();
    CACHEEnable(CACHE_IDCACHE, CACHE_INNER_OUTER);

this functions is in the file:C:\ti\pdk_am437x_1_0_10\packages\ti\starterware\examples\example_utils\example_utils_mmu.c

but the program was throwed into AbortHandler interrupt.

How to change code to access to the first address 0x1000000(physical address)?

also, I notice that in  function MMUConfigAndEnable(), there are this structure:

mmuMemRegionConfig_t regionOcmc =
            {  
                0,
                NUM_SECTIONS_OCMC, /* Number of pages */
                1U*MEM_SIZE_MB, /* Page size - Min 1MB */
                MMU_MEM_ATTR_NORMAL_NON_SHAREABLE,
                MMU_CACHE_POLICY_WT_NOWA, /* Inner */
                MMU_CACHE_POLICY_WB_WA, /* Outer */
                MMU_ACCESS_CTRL_PRV_RW_USR_RW,
                FALSE /* Non Secure memory */
            };

Please explain its function.