Hi,
In case this helps others, the solution to this issue is the firmware_loader command line option to disable i2c support. Since we don't use the tvp encoder -i2c 0 needed to be passed to the firmware loader. I had removed the kernel parameter i2c_mode=1 from vpss.ko parameter list but didn't realize this option needed to be added to the firmware loader as well. Thus far it seems no modifications to the M3 firmware is required for the 512MB configuration, though some posts suggest that modifications are required.
Thanks,
Steve