Working on a Vxworks BSP for a custom board that is based on the mpc8536rdk (but with 1GB memory) and we are getting ECC errors when system is coming up. The errors do not always happen but happen pretty much most of the time. When they don't happen system comes up fine. We are enabling ECC and waiting for DDR_SDRAM_CFG_2[D_INIT] to clear etc. and so Idont think it is due to memory not initialized correctly. Between runs the address reported (CAPTURE_ADDRESS) isnt the same. Also when I stop at the DDR exception handler, looking at the CAPTURE_ADDRESS, CAPTURE_DATA_HI and CAPTURE_DATA_LO, it looks like the memory at that address is what it ought to be (it is code, and i can compare the bytes against the disassembly dump).
The memory is a Micron MT47H128M8CF-25E IT:H. We are reusing almost all of the DDR memory settings from MPC8536RDK Uboot's code (except for the fact it is 1GB and thus some differences to CS0_BNDS and CS0_CONFIG - there is only one chip select used). I have also consulted at application note 3369,
Am wondering where the underlying cause would be that would cause this kind of a symptom.