[U-Boot] [PATCH 5/5] MX5:MX53: add initial support for MX53EVK board

[Albert ARIBAUD <albert.aribaud@free.fr>]

Le 17/12/2010 04:05, Jason Liu a ?crit :

> There is pretty much different with I.MX51 ROM,  we will not use DCD
> data file to config the
> DDR script since ROM has the DCD size limitation and use the advance
> feature of what we
> called plug-in,  the plug-in code must be in the first 2K of MMC card
> from 0x400 offset, that's
> why we need put this code section before start.S.

This implication is simply not true, as far as I can tell. You do need 
to have this "plug-in" (will you explain in the end what it is exactly?) 
in the first 2K of MMC; but that does not mean it has to be put in 
u-boot and u-boot stored at start of MMC. You could just as well put the 
"plug-in" alone in the first 2K and u-boot from the second 2K onward, 
for all I understand:

> The plug-in code
> will be called by boot ROM
> to do DDR init first and copy u-boot to DDR and jump to _start  to run it.

If it has to copy u-boot to DDR, then it should ne be part of u-boot.

> Does anyone of expert like you and Albert and Wolfgang tell me how to
> do it? It's very important for FSL
> coming many SOCs support, since we will use plug-in feature of boot ROM.

The first thing, I think, would be to get back to gathering your exact 
requirements, and only those, as per your SoC specs. From what you say 
of these, the requirements are not "have u-boot start in the first 2K of 
MMC with the "plug-in' coming first", but "have some routine in the 
first 2K of MMC, said routine assumed to do DDR init and payload copy"; 
and then, start from these reqs *only*.

Amicalement,
-- 
Albert.