[U-Boot] DDR training code for Armada 38x

[Chris Packham]

Hi Stefan,

When you did the port from Marvell's source did you script any of the
tidy-up that you did along the way?

I'm running up a new board and with the upstream u-boot DDR training
occasionally fails. But with the Marvell bootloader it doesn't fail.
The initial port was done from TIP-1.29 but Marvell are now up to
TIP-1.55 so there is probably some difference that results in my board
working.

One difference I've spotted so far is that Marvell enable 2T timing
mode for all Armada 38x boards (the comment says "resolve low freq
instability"). But doing that doesn't magically make my board work.
I'm thinking I need to compare TIP-1.29 with TIP-1.55 to look for
other differences but obviously that's going to be hard given the
style changes. If you have any scripts (or even just a record of the
regexes) that you used would you be able to share them?

Thanks,
Chris