The problem with SD card on Yoggie SOHO seems to be fixed already in a newer kernel.
[PATCH] pxamci: fix byte aligned DMA transfers
> The pxa27x DMA controller defaults to 64-bit alignment. This caused > the SCR reads to fail (and, depending on card type, error out) when > card->raw_scr was not aligned on a 8-byte boundary. aww crap, now that was the problem! I already suspected something as such (possible alignment issue), even dug down to closer inspection of raw_scr address, however didn't actually manage to find it at that time (I was more inching towards timing or transfer length issues). Thanks a _lot_, that fixed phone boot for me on my affected SD card! Andreas Mohr