On Fri, Oct 07, 2016 at 01:44:13AM +0200, Jean-Christian de Rivaz wrote:
Did you realize that SD card and eMMC uses both exactly the same signaling
and controller on all processors, not only on the Allwinner family ? If a
board designer is stupid enough to connect the eMMC instead of the SD card
on the controller looked first by the on chip ROM, then it's not an argument
to not support all the others boards that did it the right way.
Well certainly the SD/MMC controllers are not all the same. Certainly the
AM572x has 4 MMC controllers, only one of them can drive eMMC, one can
do SDIO, one is only 4 bit so best for uSD, and I forget the limits on
the last one. They have different widths and maximum speeds. So yes
they are all MMC, but they are not all the same.