In message 200905041708.59991.sr@denx.de Stefan Roese wrote:
On Monday 04 May 2009, Jonathan Haws wrote:
...
That is a good idea. I haven't thought of performing those tests. Are there specific tests I can enable in the U-Boot environment for that?
Perhaps the memory tests from the POST infrastructure. But from my experience a realworld application running under Linux is a good test. For example compiling a Linux kernel in a loop. Perhaps mounted via NFS. Something like this should fail at some time when SDRAM related problems exist.
Stefan is right. The memory tests in U-Boot all boil down to plain read-/write-cycles on the bus. This is nothing compared to the stress you put on the memory system when you have back-to-back burst mode accesses. To get these, you need a combination of cache flushes (such as in an OS when it is context-switching), cache loads (like instruction fetches when lots of different code are being executed), and DMA (like when you have heavy network traffic or another active DMA device). Booting Linux with root file system over NFS is the easiest and one of the most reliable stress tests I know of.
Best regards,
Wolfgang Denk