RTOS/AM5726: MMU setup

Eric,

I read through the thread, but unfortunately it leaves me with more questions than answers.  Please see the following configuration file that we modified from the I2C example to add two memory regions to the MMU mapping.

4466.i2c_arm_evmAM572x_master.cfg

This did not seem to work, and resulted in an exception right away when accessing the GPMC address space.

Next we added the following, which still did not work:

Finally, we added the following configuration (at runtime):

void mmu_mapping(void)
{
    Mmu_DescriptorAttrs peripheralAttrs;
    Mmu_initDescAttrs(&peripheralAttrs);
    peripheralAttrs.type = Mmu_DescriptorType_BLOCK;
    peripheralAttrs.noExecute = true;
    peripheralAttrs.accPerm = 0;
    peripheralAttrs.attrIndx = 1;
    Mmu_setFirstLevelDesc((Ptr)0x00000000, (UInt64)0x00000000, &peripheralAttrs);
}

This last configuration worked, but we have no idea why.  The only difference of significance that we can gather is that it is a first level descriptor rather than a second level descriptor.  I think part of the confusion may be that we have no idea what the different attribute parameters mean, as their documentation is non-descript.  Especially accPerm and attrIndx, but I would say the same about all of the members of the Mmu_DesciprtorAttrs structure.

Thanks,

Stuart