[U-Boot] I want to a board(tiny4412) for exyno4412, but I can't get any output

[randy]

I may mistake the sdcard, in my board, the sdcard is connect
sd2(GPK2[0:6]), using the GPK2[2] as CDn.
But it still can't work. It don't light any LED at all(in my board, it
is the low power level of gpio which the led is connected to that light
the led).
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