http://git.rhombus-tech.net/?p=u-boot.git;a=shortlog;h=refs/heads/sunxi

it's a feature that's present in quite a lot of versions of u-boot but not in the sunxi one: i added a means to check *two* MMC slots in the early SPL loader.

the problem without such a feature is: you can only boot from one MMC slot, even if you compile u-boot with support for two MMC slots... because the early SPL loader *only recognises loading u-boot from one MMC slot*.

for those people not familiar with the A20 boot process: http://linux-sunxi.org/BROM#A10.2FA20

the BROM loads from a very specific sector of either MMC0 or MMC2 (in that order). maximum code size: 16k bytes. loading a full u-boot is not possible so u-boot has to be boot-strapped (aka SPL loader). the *existing* sunxi SPL loader *only* supports loading from a *single* MMC card slot.

l.

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