Dear Emanuele Placidi,
In message 7c4b93310902180021o56da8320w2084e6a8c09c9509@mail.gmail.com you wrote:
In your opinion it is possible to probe the ram before initialize it? Unfortunately there are some rev4 which are equipped with different ram model. Examples are welcomed.
It is a standard feature in U-Boot (and has always been right from the start with PPCBoot nearly 10 years ago) that we auto-detected the memory configuration on the boards, both for RAM and flash. Some boards / architectures did not bother to implement this, but the feature itself is present.
The details depend on processor, memory controller properties, specific RAM types used, etc.
In case of the Micron/Elpida issue on the ADS5121, that should be not too difficult to solve.
Best regards,
Wolfgang Denk