[U-Boot] MMC problem in PXA270 hardware

[Andy Fleming]

On Mon, Jan 18, 2010 at 5:31 AM, Wolfgang Denk <wd at denx.de> wrote:
> Dear Vaisakh P S,
>
> In message <27208581.post at talk.nabble.com> you wrote:
>>
>> I did some more debugging, i dumped the MBR for the sdcard, and it was
>> proper in OS in board and PC.
>>
>> Here is the dump i got in OS:
>>
>> 00000000  fa b8 00 10 8e d0 bc 00  b0 b8 00 00 8e d8 8e c0
>> 00000010  fb be 00 7c bf 00 06 b9  00 02 f3 a4 ea 21 06 00
>> 00000020  00 be be 07 38 04 75 0b  83 c6 10 81 fe fe 07 75
> ...
>> But in Uboot, the dump which i got MBR read was the following
>>
>>  0xea 0xa8 0x0 0x0 0x8e 0xc0 0xac 0x0 0xa0 0xa8 0x0 0x0 0x8e 0xc8 0x8e 0xc0
>> 0xea 0xae 0x0 0x6c 0xae 0x0 0x6 0xa8 0x0 0x2 0xe2 0xa4 0xea 0x20 0x6 0x0 0x0
>> 0xae 0xae 0x6 0x28 0x4 0x64 0xa 0x82 0xc6 0x0 0x80 0xee 0xee 0x6 0x64 0xe2
>
> Seems something is eating the 0x10 bit, so 0xFA becomes 0xEA, etc.


Actually, it looks like you're losing the 0x01 bit, too.  Maybe the
u-boot driver is somehow mis-detecting how many bits are connected?
The card should be saying which bit-widths it supports, and the host
controller should be properly reporting which widths it supports.  I'm
not familiar with the pxa270's driver, but it might be possible to
modify it to only do 1-bit transfers, and see if that works.

Andy