[U-Boot] SPL boot on iMX6

[Tapani Utriainen <tapani@technexion.com>]

Hello all,

we would like to have some comments how to architecture some patches we would 
like to submit.

Background:

We have got SPL boot working, circumventing the need to have separate u-boot
binaries depending on iMX6 CPU type and memory configuration. This allows us
to have one (say) bootable SD card for all versions of our new SoMs.

Formatting the patches presents us with some questions:

1. Padconfigs. For some reason the existing padconfiguration macros are set
compile time depending on target cpu variant. Hence the need to add new 
macros (or smth) so the binary can configure the pads for many cpu variants.
This would cause duplicate and redundant sets of pad configuration macros 
for the imx6. Is there any alternative to this, more than rewriting code to 
comply with cpu specific padconfigs?

2. Is there a minimum set of features that should be supported by new boards?
(Thinking of features like fdt, fat or network boot).
It seems that most imx6 based boards have some standard features enabled by
default, but some of those we haven't tested on our new board.

Any comments regarding this are welcome,

//Tapani