In message BAY2-F24TSBmf81DMee0003463d@hotmail.com you wrote:
The u-boot starts fine on my walnut board and runs hello_world fine on that board. Does that mean the SDRAM settings are just fine? Since my linux
No, it does not.
kernel stops somewhere, I have to find a way to make sure the SDRAM runs OK.
The only real challenging test is to run Linux :-) No other test I've seen so far loads the system in a comparable way, especially when you have the root filesystem mounted over NFS, so a lot of network traffic (= DMA) is going on all the time.
All other tests more or less boil down to simple read / write accesses; this is fine to detect real hardware problems, but not sufficient to verify that burst mode accesses work reliably.
Best regards,
Wolfgang Denk