[U-Boot] MMC issues with cards formatted as SuperFloppy format?

[Robin Getz]

Andy:

I was running into a issues, and just wanted to double check that it should be 
able to be handled - and the problem wasn't in the arch specific mmc driver 
somewhere....

If you format the card with  unpartitioned Removable device ('super floppy' 
format: A super floppy layout is one in which there is no MBR, so there is no 
partition table. The entire disk (from start to end) is one giant partition.)

# dd if=/dev/zero of=/dev/sda bs=512 count=1
# mkdosfs -I /dev/sda

This will work OK in Windows and Linux hosts - it will just get mounted 
on /dev/sda. 

When I pop it into U-Boot, I get something that thinks it _is_ a DOS parition, 
with a MBR (some extra debugging turned on). and the partition offset gets 
messed up, and everything falls apart.

bfin> mmcinit
CID information:
Manufacturer ID:       03
OEM/Application ID:    5344
Product name:          SD256
Product Revision:      8.0
Product Serial Number: 544862406
Manufacturing Date:    07/08
SD Card detected (RCA 32769)
CSD information:
CSD structure version:   1.0
Card command classes:    5f5
Max trans speed: 25MHz
Read block length:       512
Write block length:      512
Card capacity:          252968960 bytes

mmc_bread: dev 0, start 16, blkcnt 1
mmc_bread: dev 0, start 0, blkcnt 1
mmc_bread: dev 0, start 0, blkcnt 1
mmc_bread: dev 0, start 0, blkcnt 1
bfin> fatinfo mmc
fat_register_device
mmc_bread: dev 0, start 0, blkcnt 1
mmc_bread: dev 0, start 0, blkcnt 1
## Valid DOS partition found ##
part_offset = 778135908
Interface:  MMC
  Device 0: Vendor: Man 035344 Snr 2079f0c6 Rev: 8 0 Prod: SD256
            Type: Hard Disk
            Capacity: 241.2 MB = 0.2 GB (494080 x 512)
disk_read
mmc_bread: dev 0, start 778135908, blkcnt 1
mmc: bread failed, status = 00000008, card status = 80000900
Error: broken fs_type sign

It looks like a problem in common fat & partition management code.

Can you confirm the same happens on your systems?

Thanks
-Robin