[U-Boot] FW: P4080 target has 16G memory stability issues ...

[Robert Sciuk]

Dear list(s),

Our P4080 target board is using 2 SODIMM's on each of 2 Controllers (4x4G DDR3), and we are seeing some memory problems (linux panics) when beating up large amounts of memory (just under the 16G), on multiple threads (7 or 8 CPUs).

Our DDR3 configuration is derived from the SPD dump of U-Boot, and we are using a version based upon the 2011.09 release of U-Boot.  Our firmware memory test, limited as it is to 2G chunks, and a single CPU shows no problem, it is only using a small test program under Linux and using multiple cpu's that we see the problems, and we can reproduce the problem at will, although reducing our memory speed via the RCW does seem to ameliorate the problem somewhat.

Questions:

	- is anyone using a similar configuration?
	- is anyone aware of limitations in the U-Boot 2011.09R version of the mpc8xxx/ddr/* code we need to be aware of?
	- any ideas?

We've been pounding our heads on this for a while now, and I'm just wondering if we are covering old territory here.

Cheers,
Rob.

Robert Sciuk
Senior Designer, R&D.
905.738.3741 xt 22621