Hi,
I'd like to know what restrictions the DM355 ROM puts on booting from SD/MMC (BTSEL[1:0] == 10).
I have managed to boot from SD cards without any problems, but have never got an SDHC card to work, presumably because the DM355 ROM doesn't like the values of the SD device registers - perhaps the access mode bits of the OCR register, or one of the many fields in the CID/CSD. The SDHC cards work fine after booting the processor via some other method.
In particular, I'd like to boot from a Sandisk iNAND device, which probably looks like an SDHC card to the DM355 ROM. The data sheet I've found for the iNAND says that it's OCR register has value 0xC0FF8080.