[U-Boot] MCI support in U-Boot

[Reinhard Meyer]

Dear Song, Elen,
> Hello Reinhard,
> 
> We planed to add MCI support in U-Boot. We found you once had a branch named “wip110202” which makes use of generic
> mci for AT91SAM9260. The commit id is 137f4defd “AT91:enable MMC on at91sam(9260/9g20/0xe)ek”.
> 
> I tried that branch. It works well with generic mci command. But now it is gone. Do you have any future plan for the
> MCI support on AT91?
> We've done something on top of wip110202 to support other AT91 EK boards. Could you point what we shall continue to
> move on?

A patch for MMC/SD making it work on at91sam9260 is here. Unfortunately I have mixed
an unrelated change (to CONFIG_SYS_TEXT_BASE) into the same patch, I have to seperate
that first before submitting to mainline u-boot.

On that CONFIG_SYS_TEXT_BASE matter, I intended to move it to start of SDRAM, making
sure u-boot relocation will not overlap (currently _TEXT_BASE is near end of SDRAM).
I know that requires a change to at91bootstrap as well. What is your opinion on this?

Reinhard